University Of Minnesota

NIH Research Projects · FY 2025 · 2022-07

PROJECT SUMMARY Neuromodulation is a rapidly growing field of study that encompasses a wide spectrum of neurotechnology that can manipulate neural circuits for treating nervous system disorders. To accelerate clinical translation of neuromodulation therapies, there is a strong need to train the next generation of scientists, engineers, and clinicians who have the knowledge base and circuit-interrogating tools to investigate nervous system disorders, the principled biophysical understanding of how neuromodulation affects neural tissue, the communication and scientific skills to work in multi-disciplinary teams, and the ability to navigate the translational pathways necessary to bring new discoveries and technologies to clinical practice. The mission of this T32 program is to train a diverse group of post-doctoral fellows, provide them with world-class opportunities to develop and translate neuromodulation technologies, and launch their careers as the next generation of leaders in the field of translational neuromodulation research. The training program will pair post-doctoral fellows with faculty co- mentors from (1) fundamental neuroscience or neuroengineering fields and (2) clinical disciplines. Fellows will conduct translational research with program faculty who are pioneers in the clinical translation of (a) deep brain stimulation therapies for neurological and neuropsychiatric disorders, (b) spinal cord stimulation for post-injury restoration of volitional movement and autonomic function, (c) peripheral nerve stimulation for treatment of cardiometabolic and inflammatory disorders, and (d) techniques for manipulating the spread of brain cancer. Fellows will participate in a clinical immersion and have the opportunity to integrate and lead aspects of research projects that are already in human clinical trials or near the threshold for first-in-human studies. The training program will also engage a cohort of resident- or fellowship-level physicians (“clinical associates”) who can devote one year of protected and already funded research time. All trainees will further develop their skills in rigorous statistical data analysis, experimental design methodologies, research quality assurance, and responsible conduct of research through hands-on workshops. We will also train the cohort of fellows and clinical associates through a translation and commercialization bootcamp with follow-up workshop sessions. This program will tap into outstanding translational neuromodulation research programs and facilities at the University of Minnesota and integrate our fellows into the unique medical device ecosystem of Minnesota, which is home to many global medtech companies that are developing neuromodulation technologies.

NIH Research Projects · FY 2026 · 2022-07

PROJECT SUMMARY Substance use is a major public health concern that disproportionately affects individuals from socioeconomically disadvantaged backgrounds. We propose the mechanistic hypothesis that childhood socioeconomic disadvantage and other aspects of social inequality leads to neurobehavioral deviations, measurable in brain structure/functioning and neurocognitive performance, that increases vulnerability to problematic substance use. Critically, the vast majority of research has been cross-sectional and relied upon small, underpowered samples of middle/upper-class White participants. In this secondary data analysis proposal, we leverage existing datasets from the Adolescent Brain Cognitive Development (ABCD) study and the Minnesota Center for Twin and Family Research (MCTFR), population-representative samples prospectively assessed at multiple time points during adolescence (ABCD) and from adolescence into adulthood (MCTFR). Multimodal and comparable structural/functional MRI assessments in both the ABCD and MCTFR cohorts allow us to develop and validate a processing pipeline for generating polyneuro risk scores indexing self-regulation abilities using whole-brain association studies (BWAS). Longitudinal and comprehensive assessments in both the ABCD and MCTFR cohorts allow us to examine whether these polyneuro risk scores mediate associations between childhood socioeconomic disadvantage and substance use trajectories in adolescence and adulthood, and assessments in both the ABCD and MCTFR cohorts, including family and community resources, household income, educational attainment, occupation, discrimination, and COVID-related stressors, allow us to examine whether more proximal experiences of social inequality in adolescence and adulthood affect substance use trajectories beyond effects of childhood socioeconomic disadvantage. The racially/ethnically representative ABCD cohort allows us to further examine whether socioeconomic status shows smaller effects for racial/ethnic minority children than White children—the marginalization-related diminished returns phenomenon. Finally, the unique twin family samples in both the ABCD and MCTFR cohorts allow co-twin control analyses that control for shared familial confounders, permitting stronger causal inference than possible in samples of singletons. Understanding effects of socioeconomic disadvantage and other aspects of social inequality on substance use trajectories is more important now than ever, given rising income inequality in the United States and the ongoing COVID-19 pandemic, which disproportionately affects individuals and families from socioeconomically disadvantaged and racial/ethnic minority backgrounds. Identifying individuals and families at the greatest risk for problematic substance use trajectories, and, critically, identifying the social and economic factors that potentially confer causal risk, will inform the development of the most targeted, and therefore most efficient, cost-effective, and efficacious, prevention and intervention efforts possible for substance misuse and use disorder.

NIH Research Projects · FY 2026 · 2022-07

Abstract Skeletal muscle accounts for 40% of body mass and defines in significant ways who we are as human beings. From the essential underpinnings of breathing, to the basic day-to-day movements of sitting, standing, and walking, skeletal muscle function enables the fullness of the human condition. Numerous skeletal muscle diseases cause marked contractile dysfunction leading to significantly diminished overall wellbeing and lifespan in humans. Therefore, preventing or reversing muscle dysfunction has significant health relevance. This proposal focuses on the sarcomere - the functional unit of striated muscle – known to underlie multiple forms of contractile dysfunction. In Nemaline myopathy, severe muscle weakness arises from hypoactive sarcomeres, while the severe muscle contractures characteristic of Distal Arthrogryposis stem from hyperactive sarcomeres. Other disorders, including inherited Muscular dystrophies, also involve altered sarcomere function. These diseases establish the sarcomere as a crucial, yet highly underserved, target for therapeutic intervention. Skeletal muscle diseases involving defective sarcomeres have no cure or effective treatments. A major challenge to progress centers on the inherent complexities of sarcomere regulation. Recently, novel ON/OFF myosin cross-bridge activation states under mechano-sensing regulatory control have been proposed to interface with the troponin- tropomyosin system to regulate contraction. Working together, through dynamic inter-myofilament signaling, this new view of sarcomere regulation has significant implications for muscle health and disease. To date, the data supporting this model derives mainly from biophysical studies, with physiological relevance unclear and critical to elucidate. We developed and validated a novel FRET-based sarcomere activation biosensor integrated into the myofilaments of intact skeletal muscle. Preliminary data shows the biosensor detects conformational changes in troponin, serving as a signaling nexus for real time reporting load-dependent inter-myofilament signaling regulation of sarcomere activation during physiological contractions in live skeletal muscles. Guiding hypothesis: Healthy skeletal muscle function requires precise sarcomere activation accomplished by dynamic inter-myofilament signaling wherein thin filament regulation initiates and myosin sustains sarcomere activation during physiological contraction; consequently, defective inter-myofilament signaling causes disease. The Aims are to investigate physiological mechanisms of inter-myofilament signaling in regulating sarcomere activation during twitch contractions in intact skeletal muscles and to investigate the effects myosin binding protein C as a key mechano-sensor governing inter-myofilament signaling processes in regulating sarcomere activation during twitch contractions in intact skeletal muscles. Elucidating the mechanisms underlying physiologically relevant mechano-sensitive inter-myofilament signaling will provide the essential framework for advancing new therapeutic discoveries to retain healthy skeletal muscle performance throughout lifespan, and to restore normal skeletal muscle function in inherited myopathies.

NIH Research Projects · FY 2024 · 2022-07

ABSTRACT The fundamental concept of Developmental Origins of Health and Diseases (DOHaD), which posits that early- life events or exposures determine the health outcomes across the life span, has been well represented by the US DOHaD Society exemplified by its annual national meeting since its inception in 2016. Its annual meeting brings together investigators with diverse backgrounds who otherwise may not likely interact, including those researching in the areas of developmental biology, life course epidemiology, nutrition, environmental toxicology, cancer, stress, and endocrinology. Such individuals span institutions across the US from universities to industry to government agencies (NIH, EPA, NIEHS) to share knowledge and recent advancements on how environmental toxicants, nutrients, pharmaceutical agents, pathogens, gut microbiota, stress, and emerging factors influence developing fetuses and newborns, and thereby contribute to their health and disease across the life span. Further, presentations also delve into how such factors might lead to harmful effects in the subsequent generations, i.e., transgenerational effects. The major goal of the US DOHaD Society’s annual meeting is to foster multidisciplinary interactions and promote collaborations on these diverse topics. The second objective is to provide opportunity for trainees (graduate students, postdoctoral fellows, and junior faculty) to interact with world-renown experts, facilitating the development of future scientists and career opportunities in the field. The third objective is to continue promoting diversity, inclusivity, and equal representation of sex, gender and underrepresented minority groups as speakers and session leaders. Notably, women and minority represented >50% and >20% speakers and moderators, respectively, over the last five meetings. The past five conferences have been enormously successful, particularly the 2021 hybrid (in-person and virtual) meeting despite the ongoing COVID pandemic. Such successes provide impetus for continued and permanent annual meetings. The 6th, 7th, and 8th Annual Meetings will again be a hybrid format and held at the University of Minnesota (Minneapolis, 2022), the Mercy’s Children Hospital (Kansas City, 2023) and the Rizzo Center (Chapel Hill, 2024), respectively. The theme for the 2022 meeting will be “Environmental Exposures: Assessment Methodologies, Mechanisms, and Health Outcomes”. Analogous to the 2021 meeting, the program will include a dedicated day on career development and grant writing that will be provided in kind to all trainees. Preliminary themes for 2023 and 2024 will cover topics including maternal microbiota and child development, exosomes as carriers of biomarkers, effects of maternal supplemental folate, choline and DHA on offspring health outcomes associated with epigenomic changes, and epidemiological analyses of long-term health outcomes associated with heat stress during pregnancy and lactation. In short, the strength of the U.S. DOHaD Society lies in its diversity in terms of the research it represents and those researching these areas.

NIH Research Projects · FY 2025 · 2022-07

Abstract Our overall goals are focus on the prevention and treatment of graft-vs-host disease (GVHD) via innate lymphoid type 2 cell (ILC2) anti-inflammatory and tissue reparative properties. We found that host ILC2s in are eliminated by total body irradiation {TBI} or chemotherapy and remain depleted for at >/=90 days. This finding is highly relevant as there is an inverse correlation between peripheral blood activated ILC2s and GVHD. As such. we sought to determine whether supplemental infusion of mature donor ILC2s could be used to prevent murine GVHD. We showed for the first time that donor ILC2s could prevent or partially treat GVHD in an amphiregulin (AREG) dependent process. Whether AREG or ILC2 direct contact with intestinal stem cells {ISC) supports small intestine epithelial cell repair in TBI treated mice or organoids is unknown. Additionally, third-party ILC2 infusion also significanUy reduced murine GVHD lethality. lmportanUy for translational purposes, we found ILC2s to be relatively steroid resistant. Peri-BMT {bone marrow transplant) IL-33 increased ST2/IL33R+ ILC2s at BMT day 0 and reduced GVHD. Ko mice had accelerated GVHD; IL-33 given pre-BMT prevented the full lLC2 loss. IL-33 ko recipients have hypo-proliferative epithelial cells, reduced ISCs and Paneth cells, and smaller crypt height and numbers. Ex vivo intestine organoid culture modeling revealed that IL-33 coordinated regeneration by inducing epidermal growth factor (EGF), significantly reduced by TBI. EGF restored ISC deficiency, uncovering a gut repair IL-33/EGF loop between ISCs and Paneth cells. Donor IL-13 ko ILC2s or host IL 13Ra ko mice had reduced GVHD. ILC2 IL 13 supports both ST2+ tuft cells and goblet cells. Tuft cells produce IL-25 driving ILC2 production and survival. TBI markedly reduced tuft cells for :!:38 days and ko recipients had a striking increase in GVHD. When given to wildtype mice exogenous IL-25 significantly reduced GVHD. Consequences of ko of tuft cells (and ILC2s) on donor T cell expansion, trafficking and function are unknown. The role of IL-25 and IL 17RB has not been examined. We will address the dynamics and interplay between ILC2, IL-33 and host intestinal cells (tuft cells, ISCs, Paneth cells) after TBI and during GVHD. Aim 1 will test the hypothesis that: Donor ILC2 repopulation fails due to destruction of ILC2 BM niche that supports ILC2s. In vitro pre-lLC2 differentiation, maturation and expansion ± proinflammatory cytokines and ILC2 supporting cytokines will be studied. GATA3-GFPhi pre-lLC2s/mature ILC2s transfer into lethally irradiated congenic BMT recipients will provide data on the differential ability to repopulate the BM. If the BM cannot support pre-lLC2s/lLC2s, we will study stem cell deficient mice. Aim 2 will test the hypothesis that: Pre-lLC2s/lLC2s and their secreted products have direct effects on intestinal cell subsets. Intestinal organoid cultures from wild-type and IL-33 ko mice with syngeneic Tregs and ILC2s will measure organoid size, number, and gene expression related to proliferation, cell cycle regulation, and specific epithelial lineage markers under homeostasis or after TBI. Anti-AREG mAbs or co-cultures with AREG ko lymphocytes will be characterized for promoting epithelial regeneration. Aim 3 will test the hypothesis that: Tuft cells are essential for ILC2 development and survival via an ILC2 release of IL-13 that stimulates tuft cells to release IL-25 that causes ILC2 proliferation (aim 3). Tuft cell and ILC2 ko hosts have accelerated GVHD. We hypothesize that IL-25 effects are due to direct stimulation of ILC2s or alternatively, with donor IL-17RB+ T cells. Significance. Studies in the R37 extension phase will provide fundamental information as to the mechanisms by which peri-BMT IL-33 diminish GVHD lethality via effects on ST2+ host ILC2s and regulatory T cells, both of which produce AREG, and the EGF/IL-33 loop that occurs between ISCs and Paneth cells resulting in small intestine repair. Further, the key role of host ILC2s in subduing GVHD, the nature of post-BMT ILC2 deficiency that occurs after pre-BMT conditioning regimens and predisposes patients to GVHD, and the essential requirement for tuft cells or their product, IL-25 will be elucidate. LasUy, critical insights will be gained as to the inability of pre-lLC2s generation, gut migration or differentiation. Translational Impact: The efficacy of donor and third-party ILC2 infusion in preventing and treating GVHD support our planned human ILC2 clinical trial, funded via other auspices, that will infuse "off-the-shelf' third party ILC2s to treat steroid refractory gut GVHD, that portends a particularly poor prognosis, in a 2- institutional study at the University of Minnesota and UNC-CH.

NIH Research Projects · FY 2025 · 2022-07

Project Summary Cardiovascular tissue engineering with pluripotent stem cells has emerged as a means to generate human cardiac tissues that can be used to model myocardial function and disease or for clinical implantation. However, existing tissue models are limited by low thickness and a lack of structural and functional maturity, due to the poor proliferative capacity, maturation, and embryonic-like phenotypes of stem cell-derived cardiomyocytes (CMs). During mammalian development, the epicardium provides critical signals to the myocardium, enabling ventricular compaction by secreting pro-mitogenic factors and contributing coronary vascular smooth muscle cells (CVSMCs) and cardiac fibroblasts (CFs) to the heart. While these cells can be harnessed to improve proliferation and maturation of CMs in vitro, there is a limited understanding of the underlying cellular mechanisms that drive these effects in human cells. In this proposal, we seek to elucidate the intermediate signals driving human epicardial-myocardial interactions by developing a 3D printed cardiac tissue model with a functional epicardial cell layer, utilizing CMs and epicardial progenitor cells (EPCs) derived from human induced pluripotent stem cells (hiPSCs). This laminated 3D-tissue model is designed to enable EPCs to undergo epithelial-to-mesenchymal transition (EMT) and migrate into the tissue bulk, and also provides a unique environment to probe ECM remodeling by epicardial derived cells (EPDCs), a process we hypothesize is one of the key mechanisms by which these cells drive maturation of cardiac tissue. Utilizing gene editing and high- throughput proteomic analysis, we will identify EPC-secreted growth factors that promote hiPSC-CM proliferation as well as EPDC-secreted ECM proteins that are critical to structural and functional maturation of cardiac tissue. We will then incorporate an epicardial layer onto a more geometrically complex model - a 3D printed, human chambered myocardial pump. We will investigate the impact of the epicardium with and without imposed volumetric pressure on pump function and clinical parameters like stroke work and ejection fraction. Insights gained from this work will expand our knowledge of developmental processes and propel the next generation of engineered cardiac tissues. These studies will, for the first time, elucidate details of epicardial-myocardial signaling in a human model and establish a link between EPDC ECM secretion and cardiac tissue maturation. Additionally, these studies will advance the structure and function of a clinically relevant myocardial pump model that has the potential to be used for drug testing, device testing, and modeling of diseases – especially those that manifest in altered pressure-volume dynamics

NIH Research Projects · FY 2025 · 2022-07

Project Summary Hypoglycemia is a serious complication of diabetes resulting from insulin treatment which can lead to cognitive deficits, brain damage, loss of consciousness, and death. A primary response to hypoglycemia is an increase in cerebral blood flow (CBF). We will test the novel hypothesis that astrocytes contribute to hypoglycemia-induced CBF increases by simultaneously monitoring astrocyte Ca2+ signaling and blood vessel diameter in the mouse cortex as blood glucose is lowered by insulin administration. We will also test whether activity-dependent increases in CBF (neurovascular coupling) is reduced during hypoglycemia and during the course of diabetes. Aim 1. Test the hypothesis that astrocytes mediate hypoglycemia-induced vessel dilation. The relation between blood glucose, astrocyte Ca2+ signaling, and vessel diameter will be determined as blood glucose is lowered by insulin administration in wildtype mice and in IP3R2 KO mice, where astrocyte Ca2+ signaling is reduced. Aim 2. Test the hypothesis that adenosine evokes Ca2+ increases in astrocytes and the release of vasodilating prostaglandins (PGs) and epoxyeicosatrienoic acids (EETs) during hypoglycemia. We will test the hypothesis that adenosine dilation of vessels acts in part by stimulating astrocytes and evoking astrocyte Ca2+ increases. PGs and EETs are released from astrocytes and dilate cerebral vessels. We will test whether one or both of these astrocyte vasodilators contribute to hypoglycemia-induced vessel dilation. Aim 3. Determine whether neurovascular coupling is altered during hypoglycemia. Increases in neuronal activity evoke local increases in CBF. This response, termed neurovascular coupling, supplies active neurons with needed glucose and oxygen. We will test whether vessel dilation evoked by whisker stimulation is altered during hypoglycemia in healthy mice. Aim 4. Test the hypothesis that neurovascular coupling is altered during hypoglycemia in a mouse model of diabetes. Aim 3 experiments will be repeated in diabetic Akita mice. These mice have been subjected to chronic hyperglycemia and represent a more accurate model of insulin-induced hypoglycemia in diabetic patients. Aim 5. Test the hypothesis that neurovascular coupling is altered during the course of long-term hyperglycemia as experienced in the Akita mouse model of diabetes. Cognitive decline is a serious and widespread complication of diabetes and may be caused, in part, by altered CBF regulation. We will determine whether neurovascular coupling is compromised during the course of diabetes in a longitudinal study in the Akita mouse.

NIH Research Projects · FY 2025 · 2022-07

ABSTRACT This project combines the mutual expertise of Drs. Patrick Rothwell and Swati More (Principal Investigators) in nucleus accumbens opioid signaling and medicinal chemistry. As part of an ongoing collaboration supported by NIDA (R21 DA050120), we have found that angiotensin-converting enzyme (ACE) has a non-canonical function in the nucleus accumbens: it degrades Met-enkephalin-Arg-Phe (MERF) and thereby regulates endogenous opioid signaling. Conventional ACE inhibitors block the degradation of MERF, leading to an enhancement of endogenous opioid signaling in the nucleus accumbens. This causes a selective reduction of glutamate release onto medium spiny projection neurons that express the Drd1 dopamine receptor (D1-MSNs), which express ACE at a higher level than other neurons. This mechanism of action has great therapeutic potential, as our preliminary data indicate the decrease in excitatory drive to D1-MSNs can diminish the rewarding effects of fentanyl. Previously published enzymatic assays using recombinant protein suggest that MERF is efficiently degraded by the catalytic N-domain of ACE, though this has not been examined in brain tissue. This raises the exciting possibility of a double-dissociation between catalytic domains of ACE that degrade angiotensin (C-domain) and MERF (N-domain). The goal of this project is to independently evaluate the contribution of each ACE catalytic domain to MERF degradation and endogenous opioid signaling in the nucleus accumbens, in order to generate new domain-specific ACE inhibitors with optimized properties for treatment of opioid use disorders. We will use mice as an experimental system to separately manipulate each catalytic domain of ACE, through a combination of complementary genetic and pharmacological manipulations. AIM 1 is to determine which catalytic domain of ACE degrades MERF in nucleus accumbens tissue. We will directly quantify extracellular levels of MERF using liquid chromatography-tandem mass spectrometry, and measure excitatory synaptic transmission using whole-cell patch-clamp recordings from nucleus accumbens neurons. AIM 2 is to determine the behavioral impact of domain-specific ACE inhibition on fentanyl CPP and self-administration. This will build on our preliminary experiments using non-contingent fentanyl exposure (CPP), by incorporating parallel analysis of intravenous fentanyl self-administration on an intermittent access schedule. AIM 3 is to optimize the central activity and drug-like properties of domain-specific ACE inhibitors. We will perform systematic chemical iterations involving (but not limited to) prodrug and drug delivery systems, with the goal of improving permeability across the blood-brain barrier. These experiments should result in the identification and early optimization of compounds that inhibit degradation of MERF by ACE in the brain. This novel mechanism could form the basis of a viable new therapeutic strategy for treating opioid use disorders.

NIH Research Projects · FY 2025 · 2022-06

Project Summary Tuberculous meningitis (TBM) is the second most common cause of meningitis in Sub-Saharan Africa. Neurologic disability and mortality are common, mortality is at least 50% in people with HIV. TBM diagnosis remains difficult and diagnostic delay/missed diagnosis are major contributors to poor outcomes. Acid fast bacilli smear of cerebrospinal fluid (CSF) is cheap and fast but with sensitivity of only ~10% in most settings. CSF culture has improved sensitivity (~50-60%) but is slow, up to six weeks. Our studies on GeneXpert MTB/Rif and the re-engineered GeneXpert MTB/Rif Ultra showed improved sensitivity (50-80%) with these rapid (~2hrs) tests. Yet, these tests have inadequate negative predictive value to rule-out TBM, require expensive instruments and cartridges, and their availability is inconsistent across the areas with the highest TB incidence. Thus, alternative or additional tests for TBM remain crucial needs to improve outcomes. A previous lipoarabinomannan (LAM) antigen test (Alere) had only ~20% sensitivity in CSF. Our study of the SILVAMP TB LAM (FujiLAM) assay in CSF found 52% sensitivity in definite or probable TBM compared to 55% for Xpert Ultra yet this study was small and requires confirmation. Of the 58 cases of definite or probable TBM, six were positive by FujiLAM but not Xpert Ultra. Eight were positive by Xpert Ultra but not FujiLAM. This study was unable to systematically and thoroughly address cases that were possibly false by FujiLAM. Further, formal cost-benefit analysis for this test, and other important tests for TBM has not been done. Given that cost remains a major limitation in accessing TB diagnostic tests, the lack of research in this area is problematic. Our overall objective is to reduce mortality and morbidity due to TBM by improving diagnostic accuracy, rapidity, and cost-effectiveness. To accomplish these objectives, the aims of this proposal are to: 1) Determine the accuracy of SILVAMP TB LAM (FujiLAM) in CSF to diagnose TBM in comparison to uniform TBM case definitions; 2) Determine whether positive SILVAMP TB LAM (FujiLAM) tests without corroboration by other TBM tests are false or true positives, using autopsy and metagenomics next generation sequencing; and 3) Determine the cost and cost-effectiveness of TBM diagnostic testing strategies, including FujiLAM and GeneXpert MTB/Rif Ultra. The first two aims focus on better defining the diagnostic accuracy of FujiLAM, an easy to use, rapid test, that requires limited technological infrastructure or expertise. The third aim focuses on cost-effectiveness of this test and other commonly used tests. These studies will impact clinical practice by better informing our understanding of the diagnostic tools for TBM. This proposal has the potential to shift the paradigm of TBM diagnosis to two rapid tests, FujiLAM and Xpert Ultra, influencing international WHO guidelines while providing valuable costing data for stake holders and ministries of health to consider investment and implementation.

NIH Research Projects · FY 2024 · 2022-06

Project Summary Identifying novelty or familiarity of the environment is required for spatial navigation and influences forming and maintaining internal spatial maps. This process of identifying an environment as novel or familiar and forming the appropriate spatial map is impaired in aging rodents and in rodent models of Alzheimer’s disease and temporal lobe epilepsy, possibly reflecting spatial processing deficits in patient populations. Recently identified spatial novelty signals from the supramammillary area to the hippocampal dentate gyrus (SuM→DG) shape spatial processing in the hippocampus; however, what signals influence SuM spatial novelty signals is unknown. This proposal investigates a novel hippocampal CA1 GABAergic projection to the SuM and its potential role in signaling spatial recognition and suppressing SuM spatial novelty signals. I term these cells HIPS (hippocampal inhibitory cells projecting to the supramammillary area), and my preliminary data indicates their fibers are near SuM→DG neurons. This proposal tests the hypothesis that HIPS signal spatial recognition, inhibit SuM→DG neurons, and influence spatial processing. I am proposing three aims to analyze the functional connectivity, behavioral impact, and in vivo activity of HIPS. I will utilize slice electrophysiology combined with optogenetic stimulation of HIPS to analyze HIPS connections to SuM→DG neurons and other neurons of the SuM (Aim 1) to test if HIPS have functional, inhibitory connections to the SuM and to test if HIPS preferentially inhibit SuM→DG neurons. To test HIPS impact on behavior and memory, I will apply in vivo optogenetics to stimulate HIPS in behavioral tasks which vary spatial and non-spatial familiarity and novelty (Aim 2). I will additionally use head-mounted miniature microscopes to perform in vivo calcium imaging of HIPS in freely behaving mice to test if HIPS’ activity reflects spatial recognition (Aim 3). This proposal provides insight into a novel hippocampal GABAergic projection and potential circuits involved in spatial recognition. This work also gives me the excellent opportunity to train in analysis of cells, circuits, and behavior using techniques which have all been successfully applied in the lab of my sponsor, Dr. Esther Krook- Magnuson. My sponsor and co-sponsor, Dr. David Redish, will fully support me in the knowledge and technical skills required for the proposal, and they are each committed to my development of professional skills needed for an academic research career. Their support combined with the resources of the University of Minnesota Graduate Program in Neuroscience will fully prepare me to pursue a career as an independent researcher.

NIH Research Projects · FY 2025 · 2022-06

SUMMARY Due to expanded clinical implementation of genetic testing and technologies across healthcare specialties, there is a huge demand for genetic counseling services in clinical, industry, public health, and academia. The roles of genetic counselors have changed and grown drastically over the 40 years since the field's inception. As the field has expanded to over 4,000, there is greater need for genetic counselors to be able to research the practice in an evidence-based fashion. At present, a two-year Master’s Degree in Genetic Counseling constitutes the terminal degree for genetic counselors, the majority who practice in clinic settings. While genetic counselors are primed to study the profession in their current roles, additional research training is needed to foster the necessary skills and methodology expertise to lead independent research programs. In recognition that the field of genetic counseling would benefit from additional research funding and that our research team is well poised to meet this need, we have created the first ever research fellowship for genetic counselors called the Genetic Counseling Fellowship in Research Training (GC-FIRST) at the University of Minnesota. Upon completion of this comprehensive 2-year, part-time research education experience, four genetic counselors will be exceptionally well positioned to contribute to the growing need for genetic counseling researchers. The overarching objective of GC-FIRST is to train genetic counselors in a range of research methodologies to promote research implementation by genetic counselors working in clinical, industry, public and population health settings. Our central goal is to educate genetic counseling researchers to be independent leaders who mentor future genetic counseling researchers. To reach this goal and attain the overall objective, we will: 1) Develop a rigorous qualitative and quantitative training in the fundamentals and advances in genetic counseling research through a series of formal coursework and training modules; 2) Provide interdisciplinary research training using a practical, application based, and collaborative approach to produce two manuscripts and a grant application; 3) Generate a diverse cohort of well-trained research clinicians that will have enthusiasm for lifelong learning to bolster the genetic counseling research workforce; 4) Evaluate the short term and long term summative and formative outcomes of the two-year fellowship. If successful, this application would create the first research training fellowship program for genetic counselors and contribute to the workforce in academic, clinical, industry, public and population health settings. An added end-product of the fellowship will be the creating and distribution of a set of online modules that will be packaged to educate an even greater number of genetic counselors with advanced research training.

NIH Research Projects · FY 2025 · 2022-06

ABSTRACT HIV-1 envelope glycoproteins (Envs) mediate viral entry into host cells and are the sole target of neutralizing antibodies. HIV-1 Envs of most primary HIV-1 strains typically exist in a closed conformation (State 1) and occasionally transit to downstream, more open conformations (State 2 and State 3). Thus, current knowledge guides immunogen design towards mimicking the Env closed conformation as the preferred target for eliciting broadly neutralizing antibodies (bnAbs) to block HIV-1 entry. However, Env preferred conformations of more than 37 million different circulating HIV-1 strains are unlikely to adopt exactly the same closed conformation. And we still do not know how different State 1 conformations of diverse natural HIV-1 variants are. Our hypothesis: State 1 Envs form a heterogenous group of Envs that exist in similar but not identical conformations. Accordingly, improved ability of bnAbs to recognize multiple Env conformations will broaden their neutralization activity. To test our hypothesis, we will assess the conformational heterogeneity of Envs from different strains and build mechanistic models for 1) Envs transitions, 2) generation and transmission of Envs that exist in specific conformations, and 3) broad recognition of different Env states. In Specific Aim 1 we will study the conformational diversity of transmitted/founder (T/F) HIV-1 strains, which can establish HIV-1 in vivo and are the only target of a preventive vaccine. We will study the mechanisms by which T/F Envs expose internal elements and how they transit to downstream conformations. In Specific Aim 2 we will investigate the generation and evolution of incompletely closed Env conformation. We will reconstruct the evolution pathway of T/Fs in patients by using available viral sequences to build evolved viruses at different time point followed by investigating changes in their conformational states over time. In parallel, we will study Env conformational diversity among HIV-1 strains that are archived in the latent HIV-1 reservoir of people living with HIV-1 and identify potential targets for therapeutic interventions. These approaches will allow us to build a mechanistic model for how incompletely closed Envs are generated, evolved, and transmitted. In Specific Aim 3 we will define important parameters for broad recognition of CD4-binding site (CD4-bs) on different Env conformations of diverse primary strains. We will study how the exceptionally broad N6 (CD4-bs) bnAb recognizes different Env conformations, will identify critical interactions with residues on open and closed Env conformations, and will solve cryo-EM structures of HIV-1 Envs in complex with N6 to define the mechanism of broad recognition. Overall, our study will provide high-resolution and comprehensive view on the biology of HIV-1 entry pathway, will refine the knowledge on HIV-1 Env conformations, and will form a strong basis for the development of new strategies for HIV-1 cure and vaccine design.

NIH Research Projects · FY 2025 · 2022-06

PROJECT SUMMARY Coronavirus Disease 2019 (Covid-19) is a devastating worldwide pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). In the United States alone, there have been over 35 million confirmed cases and Covid-19 has claimed more than 600,000 lives, and the pandemic is still rampant around the globe. While SARS-CoV-2 can infect people at all ages, senior populations are at greatest risk of severe disease and worse outcomes. Although Covid-19 is initially a respiratory disease, it subsequently causes damage to multiple organ systems, including the brain. Clinical findings indicate that neurological symptoms are widely observed in patients with Covid-19 and approximately 33% of Covid-19 survivors suffer from persistent neurological impairment. Emerging evidence also shows that people carrying the apolipoprotein (APO) E4 gene, the strongest genetic risk factor for late-onset Alzheimer’s disease (AD), are more susceptible to SARS-CoV-2 infection with higher severity and mortality than people carrying the APOE3 gene. In addition, older adults with AD or other dementias are at a higher risk of contracting Covid-19 and experiencing more severe outcomes than are people without dementia. These findings suggest that age, APOE genotype, and AD/dementia status modify the risk, severity, and outcomes of SARS-CoV-2 infection, although the underlying mechanisms are unclear. Further, while the acute effects of Covid-19 on brain functions are well documented, the long-term impact of SARS-CoV- 2 infection (“long-Covid”) is currently unknown. We hypothesize that the interactions of SARS-CoV-2 with age, APOE genotype, and the context of AD-type neuropathology at the blood-brain and blood-CSF barriers modulate both systemic and neuroinflammation, dictating the effects of SARS-CoV-2 infection on brain function. Three independent yet interrelated specific aims are proposed to test the hypothesis, using multiple mouse models and a combination of virology, immunology and neurobehavioral approaches, coupled with innovative targeted and unbiased cellular, molecular technologies, including single cell/nucleus transcriptomics, spatial genomics, and 3D brain clearing and imaging. Aim 1 is to assess the acute and long-term impact of SARS-CoV-2 infection on neuropathophysiology in normal aging in WT mice. Aim 2 is to define the interaction of SARS-CoV-2 with different APOE isoforms and its impact on the temporal onset and severity of cognitive impairment and neuropathology in human APOE4/4 and APOE3/3 mice. Aim 3 is to evaluate the impact of SARS-CoV-2 infection on the progression of cognitive deficits and AD neuropathology in APP/PS1 transgenic mice. Results from these proposed studies are expected to define the short- and long-term impact of SARS-CoV-2 infection on cognitive function and pathogenic processes in aging and AD, and provide novel insights into the underlying cellular and molecular mechanisms so that effective interventions may be developed to prevent the neurological and neurocognitive sequelae from SARS-CoV-2 infection in aging and AD.

NIH Research Projects · FY 2025 · 2022-06

Premise: The combination of selectivity and affinity afforded by biomolecules such as antibodies for their target ligands make them ideal recognition elements for bioassays. While these affinity reagents have enabled the development of many important bioassays, these measurements are almost always performed as static analyses at an individual time point. The slow off rates of affinity reagents makes development of responsive assays that can monitor changes in analyte concentration over time a challenge. Reagent degradation, non-specific surface interactions, and biofouling present additional difficulties. Our goal is to develop an online, flow-through, affinity assay that can continuously monitor the efflux of biochemical messengers from dynamically changing biological systems in real time. Our premise is that microfluidic integration of a perfusion chamber, online mixing of affinity reagents and continuous micro free flow electrophoresis (µFFE) separations will directly address limitations that have restricted the development of time responsive affinity-based assays to date. Innovation: We will use a microfluidic, flow through approach to develop time responsive affinity assays. The biological model (i.e., cell culture) will be housed in a perfusion chamber. Perfusate will be mixed online with a fluorescently labeled affinity reagent (i.e., antibody or aptamer) that selectively binds the target analyte. Online µFFE will then be used to continuously separate the analyte-affinity reagent complex from excess affinity reagent in real time. Online affinity µFFE offers several advantages. Continuous flow removes off rate as a limitation to temporal response. Exposure to the biological matrix is minimal, mitigating reagent degradation. Signal is measured in solution, limiting the effect of non-specific surface interactions and biofouling. µFFE separation enables interference free measurement of the analyte-affinity reagent complex even when the affinity reagent is applied in large excess, improving the LOD of the assay. Approach: Affinity µFFE assays will be developed for representative analytes from three biochemical messenger systems: neuropeptide Y (NPY, neurotransmission), leptin (energy regulation), and tumor necrosis factor α (TNF-α, immune response). Direct comparisons will be made between assays that use antibodies (Aim #1) or aptamers (Aim #2) as the affinity reagent. Figures of merit that will be used to assess assay performance include: LOD, temporal response, minimum detectable change, and long-term stability. Once fully optimized, affinity µFFE assays will be used to continuously monitor both baseline and stimulated efflux from cell models for neurotransmission (neurons), energy regulation (adipocytes) and immune response (mast cells). Benchmarks: We anticipate that affinity µFFE will achieve the following performance metrics: LOD ≤ 1nM; temporal response ≤ 1 s; minimum detectable change ≤ 5%; and long-term stability ≤ 10% over 4 h. Impact: Time responsive µFFE assays will allow researchers to study dynamic changes that occur on a ≤1 s timescale in several critical biochemical messenger systems for the first time.

NIH Research Projects · FY 2026 · 2022-06

Project Summary Chronological age is the leading risk factor for most chronic diseases, frailty, and mortality worldwide. Thus, the elderly population usually has multiple chronic conditions at the same time, resulting in poor health and reduced quality of life (prolonged morbidity period) at the later stage of life. There is a big challenge to compress morbidity period and increase healthspan (lifespan with good health). In this project, we propose to examine the role of p21high senescent cells in lifespan and healthspan. We have generated and validated a new p21-Cre transgenic mouse model containing a p21 promoter driving a bicistronic message consisting of Cre fused to a tamoxifen- inducible estrogen receptor (ER) element. This model enables us to monitor, sort, kill or modulate p21high cells with aging in vivo. Our preliminary data shows that p21high and p16high cells are two distinct cell populations, and the p21-Cre mouse model targets 1.5-10% of cells in various tissues in 23-month-old mice. Monthly clearance of p21high cells in mice starting at 20 months reduces frailty index, extends lifespan, and more importantly, improves physical function at the end of life. In this proposal, we will further characterize the role and mechanisms of p21high cells in lifespan and healthspan. Our overarching hypothesis is that targeting p21high cells can extend lifespan and compress morbidity in old age. In aim 1.1, we will investigate whether clearance of p21high cells could extend lifespan and healthspan using a larger group size. We will examine potential sex difference and perform postmortem pathological analysis to examine the cause of death and disease burden. Moreover, we will follow physical function and frailty index of these mice every month from 20-month-old to the end of life to assess late life health status. In aim 1.2, we will leverage p21-Cre mouse models to sort and enrich p21high cells from 6 tissues of 23-month-old mice where we observed p21high cells (2-10%), and perform single cell RNA sequencing on these cells along with non-p21high cells. In addition, we will perform single nucleus sequencing and imaging mass cytometry. In aim 2, we will investigate the role of NF-κB pathway in p21high cells in lifespan and healthspan shortening. This project is likely to have a broad impact on aging research by gaining a comprehensive understanding of p21high cells at both functional and transcriptomic levels in vivo. Results from this project will also enable future testing of pharmacological interventions that eliminate these cells to improve lifespan and compress morbidity.

NIH Research Projects · FY 2025 · 2022-06

PROJECT ABSTRACT Over 100 million US adults have hypertension, the number one chronic disease risk factor in the world. The United States Preventive Services Task Force and the 2017 American College of Cardiology/American Heart Association blood pressure (BP) guidelines recommends measuring BP outside of the clinic for the diagnosis and management of hypertension. Home blood pressure monitoring (HBPM) involves self-measurement of BP by the patient and is the most common method for assessing out-of-office BP in the US. The guideline recommendations are based on high-quality observational studies in which out-of-office BP was typically obtained at a single point and individuals with high out-of-office BP were observed to have higher rates of cardiovascular outcomes and increased rates of all-cause mortality, regardless of office BP levels. Additionally, clinical trials have demonstrated that HBPM reduces clinic BP over short 6-12 month time frames, especially when combined with disease management programs. There are no studies evaluating the effectiveness of HBPM in routine clinical practice in a diverse population from across the country. Additionally, there are a lack of data on: a) whether use of HBPM reduces risk for clinical outcomes; b) the impact of HBPM on both short- and long-term clinic BP, clinical inertia, and medication adherence in routine clinical practice; and c) how clinicians and patients utilize HBPM. Over the last ~10 years, approximately 400,000 Veterans have measured home BPs as part of the VA’s telehealth program. We propose to identify Veterans age 18-90 years with uncontrolled clinic BP enrolled in HBPM programs and a cohort of Veterans not enrolled in HBPM programs. We will link telehealth data to clinical and outcome data. The proposal will make use of the large number of patients enrolled in the VA’s HBPM program and the variation in how the HBPM program is implemented across VA sites. In Aim 1, we will evaluate the effect of HBPM on major adverse cardiovascular events, non- cancer mortality, and adverse events. In Aim 2, we will assess the impact of HBPM on clinic BP, BP medication intensification, and medication adherence. In Aim 3, we will determine facility-, provider-, and patient-level factors associated with use of HBPM in routine practice. Results will establish a) the long-term benefits of HBPM, b) the association between HBPM and clinical events, and c) the effects in important subgroups. These findings will inform selection of patients for and the design of a much-needed randomized controlled trial evaluating the effect of HBPM on clinical outcomes compared to office-based hypertension management. Additionally, identifying factors associated with greater reductions in BP and greater number of home BP values transmitted, such as case management programs, may identify barriers to adherence that can be addressed and inform implementation strategies and the use of HBPM in clinical practice. The proposed study will answer questions critically important to implementation of HBPM in routine clinical practice with the ultimate goal of reducing the morbidity and mortality associated with hypertension.

NIH Research Projects · FY 2026 · 2022-06

Project Summary Mixed neuropathologies are the most common cause of the clinical syndrome of dementia, including Alzheimer's disease (AD), Lewy body dementia (LBD) and frontotemporal dementia (FTD). Exploiting novel constitutive and conditional knockout lines as well as transgenic mouse lines, we now propose a series of genetic approaches designed to uncover key knowledge gaps linking alpha-synuclein (αSyn) and tau biology, pathologies and their relationships to synaptic and cognitive function. Leveraging emerging evidence from independent groups including our own, we will test the central hypothesis that αSyn expression, independent of αSyn pathology, may impact the biology tau and/or tau-dependent pathology. In the light of novel findings reported in the preliminary results, we will i) test the hypothesis that αSyn regulates human tau selectively, but not mouse tau, ii) test the prediction that constitutive ablation of the SNCA gene encoding αSyn alleviates tau pathology and tau-induced cognitive deficits in a model of tauopathy, iii) test the hypothesis that conditional ablation of SNCA in forebrain excitatory neurons alleviates tau pathology and tau-induced cognitive deficits in a model of tauopathy, thereby providing a preclinical proof-of-principle that targeting this αSyn/tau coupling might be therapeutically beneficial in the context of FTD and LBD.

NIH Research Projects · FY 2025 · 2022-06

Project Summary/Abstract: Chronic stress promotes a systemic inflammatory response that contributes to cardiovascular and metabolic disease (CVD), and even acutely augmented stress can exacerbate disease severity. In humans, consumption of high fat/high cholesterol diet (HFD) is a common co-factor driving chronic stress responses. Understanding mechanisms controlling the stress-response and its association with CVD diseases, which are nearly ubiquitous and a leading cause of mortality, will allow for development of impactful translational approaches to fight against this understudied disease. The AG is the primary source for steroid hormones, corticosterone and aldosterone that are produced in the cortex. Elevated corticosterone modifies glucose homeostasis, immunity, and tissue remodeling. Our prior work using a cold-temperature stress model showed that cold-stress drives the promotion of monocyte egress from bone marrow and exacerbated atherosclerosis. Therefore, we sought to determine whether the local immune cells in the AG were also responding to stress responses, either through cold-exposure or HFD feeding. Interestingly, we observed accumulation of lipid within AG resident macrophages sitting adjacent to hormone-producing endocrine cells in models of atherosclerosis, hypertension, or acute cold challenge. Tissue resident macrophages are typically tissue repair cells and lipid accumulation is associated with anti-inflammatory phenotypes in macrophages. AG macrophages have not been thoroughly described in literature, and their function in response to hormone signals is unknown. Through our preliminary studies of WT mice (chow-diet fed with no overt stressors), we identified two primary populations of macrophages present in the AG. These populations showed a sexual dimorphism in the representation of macrophage subsets when comparing adult male versus female mice. Furthermore, through single cell RNA- seq profiling between male and female AG immune populations, we identified gene programs associated with AG resident macrophages and found constitutive expression of the lipid-sensor Trem2, which was found to increased on AG macrophages following chronic challenge, supporting a role in responding to lipid-hormones. Loss of Trem2 was associated with lipid accumulation in the AG and elevated circulating corticosterone levels in the absence of challenge. Together, these observations led to the overarching hypothesis AG resident macrophage maintenance is controlled by sex hormone production, and that AG macrophages sense steroid hormones during stress responses to dampen inflammation and promote tissue health. Our extensive experience in studying tissue macrophage development and function, along with the utilization of new animal models make our group ideal to test these novel concepts. If true, the implications of this study will identify new approaches to regulate systemic inflammation responses through the modulation of AG associated macrophages, which might complement current lipid-control approaches used for high-risk CVD patients.

NIH Research Projects · FY 2026 · 2022-06

ABSTRACT Age-related decline in physical and cognitive health are pressing public health concerns. Developmental science shows that variation in adult physical and cognitive health is reliably associated with individuals’ early experiences in their families of origin. Risky families, characterized by greater conflict and lower-quality parenting, tend to disrupt psychosocial and biological functioning, resulting in increased risk for diseases, including Alzheimer’s Disease and Related Dementias (ADRD). Children who receive less warmth, support, and responsiveness from their parents typically have higher inflammation levels, blood pressure, and allostatic load, indicators that predict future cardiovascular problems. These pathways are also implicated in altered midlife cognitive functioning and confer risk for Alzheimer’s Disease and Related Dementias (ADRD). This project takes advantage of an unparalleled opportunity to further this important line of work on the significance of family experiences in adolescence for health outcomes in adulthood by conducting a follow-up into midlife of the Sibling Interaction and Behavior Study (SIBS). SIBS is a longitudinal study of 409 adoptive and 208 non-adoptive families. The offspring in these families have already completed intake (in mid-adolescence), and three follow- up assessments. In the first assessment of SIBS, already coded direct observations of parent-child interactions, as well as parent-reports and child-reports of the quality of the parent-child relationship, were acquired. The availability of these relationship data at a key developmental phase in an adoption cohort provides a strong platform for the addition of follow-up data on the target participants/younger generation (YG; M age = 38 years) and their parents/older generation (OG; M age = 71 years). Our overarching objective is to investigate the degree to which family experiences in adolescence predict key indicators of health in adulthood among adoptive and non-adoptive adults and their aging parents. Specific aims of this project include: AIM 1: Determine the longitudinal effect of adolescent family experiences on later physical health and cognitive functioning in adult children (YG) and their aging parents (OG); AIM 2: Model the environmental impact of adolescent family experiences on later physical health and cognitive functioning; AIM 3: (a) Test whether the effects of family experiences extend to subtle indicators of physical health; (b; exploratory) and are moderated by APOE status.

NIH Research Projects · FY 2026 · 2022-06

SUMMARY Dendritic cells (DC) are responsible for directing T cell responses and macrophages important for modulating tissue inflammation. A hallmark of these immune cells is their inherent plasticity to govern immunity vs. tolerance. However, much remains unknown regarding the complex molecular networks that collectively govern hematopoiesis, inflammation and antigen presentation. Incomplete understanding presents major obstacles to delineating their underlying roles in health and disease, which has also hindered success in developing effective immunotherapies. The long-term goal of the proposed research is to determine how pivotal immunoregulatory proteins govern DC and macrophage differentiation and immune responses. Published findings by my laboratory have begun to mechanistically define the functional roles of several important genes uniquely expressed in these myeloid cells. These genes, which include Allograft Inflammatory Factor-1 (AIF1) and Phosphodiesterase 1b (Pde1b), among others, were identified using a combination of high throughput transcriptomic profiling coupled with rigorous RNAi functional screening. My laboratory demonstrated that AIF1 is selectively expressed in conventional type 1 DC (cDC1), monocyte-derived DC (MoDC) and macrophages and serves as a scaffold to recruit protein kinase C (PKC) in a calcium-responsive manner to promote inflammation and type 1 polarized immune responses. Furthermore, AIF1 expression was required for successful generation of cDC1 from hematopoietic progenitors and both MoDC and macrophages from monocyte precursors. In the context of disease, AIF1 expression in DC and macrophages is required for initiating and sustaining insulitis and in regulating effector responses to intracellular pathogens. In another line of studies, the phosphodiesterase protein Pde1b was found to depress protein kinase A (PKA) activity in a calcium-dependent manner by regulating cyclonucleotide levels in cDC1, MoDC and macrophages to promote immune effector responses. Thus, my research group has begun to unravel how Pde1b works in concert with AIF1 to govern immunity by balancing PKC vs. PKA activities. As important as these initial findings are, there remains several gaps in understanding the molecular mechanics of how these genes govern immunobiology. As such, our research builds on prior studies by now employing conditional and global knockout mice and use of innovative experimental tools to rigorously study mechanistic roles in vivo. My laboratory will pursue the following major goals over the next five years: (1) delineate how AIF1 and Pde1B govern differentiation of DC and macrophages in vivo; (2) describe the intracellular processes by which other key novel immunoregulatory genes orchestrate immune responses; (3) determine the contributing role of AIF1 in initiating inflammation and sustaining autoreactive T cell responses; and (4) identify how intracellular pathogens antagonize AIF1 and Pde1b through disruption of calcium signaling and cyclonucleotide levels to evade host immunity. Knowledge gained will fill key gaps in our understanding of DC and macrophage biology and provide important insights into the molecular networks governing immunity.

NIH Research Projects · FY 2026 · 2022-06

The Addressing Alzheimer’s Disease and Related Dementias Disparities: The American Indigenous Cognitive Assessment (AMICA) Project tackles the significant dementia disparity that exists for Indigenous populations by determining the scalability of recently developed, culturally tailored, brief cognitive tests for dementia for use in diverse American Indian (AI) populations. Compared to the majority population, Indigenous rates of Alzheimer’s disease and related dementias (ADRD) are approximately 3 times higher. This research will adapt and validate a battery of complementary Indigenous cognitive assessment tools developed in Canada and Australia for use among AI populations in the United States. This battery expands and adapts the Canadian Indigenous Cognitive Assessment (CICA), as well as the Australian Kimberley Indigenous assessments for depression (KICA depression), Activities of Daily Living (KICA-ADL) and a caregiver report (KICA-Carer). Culture and context are central to Indigenous peoples’ experience with dementia and dementia diagnosis. Due to significant cultural differences between tribal populations in Australia, Canada, and the US, existing Indigenous culturally valid clinical tools cannot be used in the US until they are first adapted and re-validated. Until unbiased tools are developed, we run the risk of basing critical clinical and policy decisions on flawed epidemiological estimates of ADRD which, in turn, further exacerbates dementia inequities. Using community- based participatory research approaches blended with Indigenous methodologies, we will revise existing Indigenous assessments to align with AI cultural context as well as the neuropsychiatric properties. We intend to measure and assess the reliability, validity, and cultural acceptance of the adapted instruments with a total of 390 dyads of people with dementia and their caregivers (n=780) in in two culturally distinct tribal communities in Minnesota, Wisconsin, and an urban AI population in New Mexico. Our central hypothesis is that developing a culturally safe cognitive assessment approach that accounts for cultural context will provide accurate diagnoses, which in turn will help us achieve our long-term goal of improving the diagnosis and care of Indigenous persons with dementia across the ADRD continuum. Our specific aims are to: 1) create American Indian appropriate versions of the CICA Cog, KICA Carer, KICA depression and KICA-ADL (the “AMICA battery”); 2) assess the psychometric properties and cultural acceptability of the four tools in the AMICA battery. We hypothesize that the AMICA battery will demonstrate strong reliability, validity, sensitivity, specificity, positive and negative predictive value relative to the two-eyed seeing consensus diagnosis. Thus the AMICA battery will produce the same diagnoses, while providing greater cultural safety, than the standard assessments. By achieving these aims we can expect to deliver the first culturally adapted valid cognitive assessment battery for American Indian older adults. In doing so, this research will help to reduce disparities, accelerate research, and enhance access to high quality clinical practice.

NIH Research Projects · FY 2025 · 2022-06

Project Summary/ Abstract A growing share of Medicare beneficiaries are enrolled in Medicare Advantage (MA) rather than traditional fee- for-service (TM) Medicare, with the MA share increasing from 13% in 2004 to 39% in 2020. The Centers for Medicare and Medicaid Services (CMS) pay MA plans a monthly capitated rate to cover nearly all health care expenses for plan enrollees. MA plans keep as profits the portion of payments that are not used to cover enrollee expenses. In addition, CMS grants MA plans greater freedom to manage enrollees’ health care use, for example, through tools such as narrow provider networks and broader coverage of delivery innovations such as telemedicine. Proponents argue that these financial incentives and effective tools for MA plans might enable them to provide care more efficiently than TM. On the other hand, these effects could be offset by financial incentives under capitation to limit service provision beyond what is necessary to improve short term health, resulting in adverse impacts on longer-term outcomes. Prior work has primarily estimated cross-sectional comparisons of TM and MA enrollees, which could lead to biased estimates if MA enrollees differ from TM enrollees in other ways that are related to health care use and health outcomes. Our proposed project will study changes in MA enrollment coming from seven states that recently changed public retiree health benefits from supplemental TM coverage to mandatory MA plans (or in one state, from a mandatory MA plan to supplemental TM coverage). We will use these natural experiments, along with comprehensive Medicare data for TM and MA enrollees, to estimate the causal impact of MA enrollment on health care use, quality, and patient outcomes. These results will provide important evidence to policymakers weighing broader expansions of Medicare Advantage.

NIH Research Projects · FY 2025 · 2022-06

Project Summary/Abstract Microglia, resident immune cells of the central nervous system, utilize G-protein signaling to accomplish different tasks. Gi-signaling is used to perform process outgrowth, while Gs signaling is engaged during periods of neuronal hypoactivity (such as anesthesia). However, very little is known about microglial Gq calcium signaling. Partially, this is due to the fact that microglia rarely display calcium transients at rest. On the other hand, microglia greatly elevate their calcium signaling in the period that follows status epilepticus—a prolonged seizure state predictive of later epilepsy development. The purpose of microglial calcium signaling during epilepsy development is not known, but is hypothesized to be a component of microglial phagocytosis. Most microglial calcium signaling in epilepsy development is attributable to P2Y6 receptor signaling—a Gq-calcium receptor activated by a key purine. P2Y6 is best described for its role in phagocytosis, but that has not been fully explored in epilepsy development. (Innovation) The current proposal will utilize a novel mouse line that allows for the simultaneous examination of microglial calcium activity and process movement in the living animal (using two- photon microscopy). (Aim 1) This line will be used to test the role of P2Y6 in microglial phagocytosis, after neurons are selectively killed through excitotoxicity using optogenetic techniques. In parallel, tissue studies will be conducted across key time points in epilepsy development to determine if the loss of the P2Y6 pathway prevents proper clearance of dead/dying neurons after status epilepticus. The prolonged presence of dying neurons is pro-inflammatory and hypothesized to negatively affect neuronal network dynamics in the long term. (Aim 2) For these reasons, we will test multiple aspects of long-term P2Y6 signaling loss during epilepsy development. We will determine the long-term pro-inflammatory effects of P2Y6 signaling loss. Additionally, we will use miniscope technology and 24/7 video EEG to determine whether the loss of P2Y6 calcium signaling and its putative phagocytosis alters network dysregulation or epilepsy risk. The proposed research will enhance the candidate’s experience in using advanced techniques to probe neuronal circuit function. Such training is directly related to the candidate’s goal of independently studying key glial pathways and how they influence complex neuronal circuits during epilepsy development. These studies will be performed at the Mayo Clinic under the supervision of experts in glia (Dr. Long-Jun Wu), epilepsy (Dr. Greg Worrell and Dr. Peyman Golshani), and miniscope technology (Dr. Luis Lujan and Dr. Peyman Golshani).

NIH Research Projects · FY 2026 · 2022-06

Alzheimer’s disease (AD) and many related dementias (ADRDs) are tauopathies, characterized by somatodendritic accumulation of tau and intraneuronal inclusion bodies composed of tau species that have undergone extensive post translational modification. Although some disease-specific Tau modifications have been identified, many are conserved across the full range of tauopathies. We do not yet have a deep understanding of the molecular processes that generate these tau protein modifications, or of their functional consequences in promoting pathogenic cascades. This knowledge gap is a major contributor to our current inability to generate effective therapeutic interventions for AD and other tauopathies. The central hypothesis we are testing here is that a range of pathogenic events induce phosphorylation of tau at specific residues, resulting in mislocalization of tau within the cell and subsequent synaptic dysfunctions, and that inhibition of these early tau phosphorylation events will in turn inhibit tau pathologies and associated signaling deficits. This hypothesis is based on our published work, primarily utilizing cultured cell experimental systems. The direct relevance of this mechanism to human disease is further supported by the recent finding that phosphorylation of tau at these same specific residues is an early event preceding tau fibril formation in AD disease progression. Our overall objective here is to test and further refine this hypothesis in a novel mouse model we have developed (MAPT- GR) that expresses all isoforms of human tau at physiologic levels and ratios. We have found that mild traumatic brain injury (mTBI) induces a rapid phosphorylation and somatodendritic mislocalization of the human tau in these mice. Importantly, we can prevent this tau mislocalization by inhibiting phosphorylation. The specific aims are to: 1. Determine the dynamic changes in the subcellular distribution of phosphorylated tau. We will utilize our novel tauopathy model to test the working hypothesis that phosphorylation of tau at specific residues leads to somatodendritic accumulation of tau, tau mislocalization to dendritic spines, and alters micro- components of dendritic spines. 2. Determine the synaptic and circuit dysfunctions associated with the phosphorylation of tau. We will test the working hypothesis that mislocalization of phosphorylated tau to somatodendritic domains and dendritic spines results in synaptic and circuit dysfunction in our model. 3. Identify the impact of inhibiting these early phosphorylation events on tau mislocalization and associated signaling deficits. We will test our working hypothesis that mTBI activates GSK3β and CDK5, which phosphorylate the B and C domain of the tau protein. Expected Outcomes: We expect to identify the early-stage pathologies and dysfunctions caused by phosphorylation of tau and provide proof-of-concept demonstrations of the extent to which these dysfunctions can be prevented by blocking tau phosphorylation at specific residues. Of equal importance, we expect to have optimized a model and experimental platform in which potential therapeutic compounds that target this common disease mechanism can be tested and optimized.

NIH Research Projects · FY 2025 · 2022-05

PROJECT SUMMARY Caregiver Speech and Brain-Behavior Development in Infants At-Risk for Autism Spectrum Disorder The defining symptoms of autism spectrum disorder emerge only after an initial presymptomatic period during the first year of life. The first year of life is also a time of tremendous growth and neuroplasticity for the infant brain. The overall goal of the proposed longitudinal study is to enable and inform presymptomatic infant interventions for autism by examining the relationships between infant vocalizations, caregiver speech, and brain-behavior development in infants at high familial risk for autism. Conceptually, the project focuses on the potential protective effects of caregiver speech on infant development. The proposed study is a companion to and collaboration with the IBIS Network-Early Prediction Study, an NIH-sponsored study of 250 infants at high familial risk for autism. All infants in the study have an older sibling with autism. These high-risk infants have a 20% probability of developing autism themselves. Ecologically valid day-long home language recordings will be collected when infants are 6 and 12 months of age. A state-of-the-art automated processing pipeline will used to estimate daily counts of infant and caregiver speech quality and quantity. Micro-level targeted annotation will be applied to semi-structured, parent-infant play sessions collected in the lab. Automated processing pipelines and micro-level targeted annotation will be used to generate multivariate infant vocalizations and caregiver speech data. Infant vocalizations will be classified as speech-like or non-speech-like (delight or distress). Caregiver speech variables include lexical diversity, mean length utterance, and temporal contingency. The study will determine if infant vocalizations predict subsequent autism diagnosis and later language and social communication scores, and specify the relationship between caregiver speech and infant communication skills. Diffusion MRI will be collected when infants are 6, 12, and 24 months of age by the Early Prediction Study. The proposed study will determine if multivariate caregiver speech is related to targeted prefrontal and temporal brain regions. By determining if caregiver speech can have a protective effect on brain development, we forge a new scientific approach to studying communication development in infants at high-risk for autism. As first-year autism detection and presymptomatic intervention become increasingly feasible, an evidence base is needed to inform interventions. The proposed study will identify infant-based language and communication risk markers, caregiver-based intervention targets, and brain-based monitoring biomarkers to guide presymptomatic intervention for autism that is parent-mediated and delivered in the natural setting.