University Of Florida

NIH Research Projects · FY 2026 · 2022-06

The United Nations estimates that nearly 8 million people of Venezuelan descent (PVD) have fled their home country since 2015. At present, PVD are among the fastest-growing groups in the United States (US). Remarkably, almost no systematic research—excluding our formative work—has examined the wellbeing of PVD in the US. Findings from our cross-sectional formative research with convenience samples of PVD youth and parents suggest that depression and alcohol misuse are critical challenges for this population, and that many PVD are exposed to high levels of stress. To address this critical research gap, we aim to conduct the definitive study of the PVD in the US with a comparison sample in Colombia—a study that will provide knowledge vital to addressing the immediate and longer-term needs of PVD families, and inform future efforts to support families exposed to high levels of stress, as well as challenges related to depression and alcohol misuse. The comparison with PVD in Colombia is essential for identifying aspects of life in the US that may uniquely informing context-specific and cross-national solutions to a hemispheric challenge. We examine how exposure to stress influences family functioning and, in turn, parent and youth behavioral health outcomes (i.e., depression, alcohol misuse). We also examine how key protective factors buffer the effects of stress. This research project is oriented around three specific aims: [1] Identify risk and protective factors related to depression and alcohol misuse among PVD youth and their parents, recruiting dyads in the US (n = 500) and Colombia (n = 250). [2]: Determine the mechanisms by which risk factors (e.g., hunger, stress) impact depression and alcohol misuse among PVD families. We hypothesize that exposure to stress will negatively influence family functioning and, in turn, increase risk of depression and alcohol misuse among youth and parents and that exposure to multiple forms of stress will amplify this relationship. [3] Disseminate findings to accelerate efforts to support PVD families, via reports and in-person and online workshops to help clinical and health providers to improve practice. We have designed a study that will provide critical insight to address the needs of PVD families immediately. Moreover, it will yield practice-relevant knowledge generalizable to inform future efforts to support families exposed to high levels of stress, as well as challenges related to depression and alcohol misuse.

NIH Research Projects · FY 2025 · 2022-06

DNA methylation is an epigenetic modification involved in transcriptional regulation of genes involved in development and differentiation, and its deregulation contributes to human pathogenesis. It is catalyzed by the family of DNA methyltransferases including catalytically active Dnmt1, Dnmt3a, Dnmt3b. DNA methylation plays a major role in preimplantation development in mice. To establish a new epigenome, the mouse zygotic genome undergoes epigenetic reprogramming, including global DNA demethylation at the 8-cell stage. Upon implantation, a wave of de novo methylation in epiblast cells mediated by de novo enzymes Dnmt3a and Dnmt3b results in new methylation patterns maintained by Dnmt1 that form a basis for tissue-specific expression and differentiation. Dnmt3b regulates developmental and imprinted genes, X chromosome inactivation, pericentromeric regions, gene bodies and other genomic regions. Its importance in mouse development was demonstrated by embryonic lethality of Dnmt3b-/- mice. We recently found that Dnmt3bCI/CI mice expressing catalytically inactive Dnmt3bCI protein survived both pre- and postnatal development. Molecular analysis suggested that accessory function - the ability to recruit other Dnmts to proper genomic loci – of Dnmt3b rather than its catalytic activity, is important for methylation and survival. Here we hypothesize that Dnmt3b is a multifaceted protein whose various activities involved in methylation affect pre- and postnatal development and are critical to prevent disease formation in mice. To test this hypothesis, in Aim 1 we analyze global methylation and expression at different stages of development in mice lacking various Dnmt activities to determine the scope of Dnmt3b’s accessory function in Dnmt3a-mediated de novo methylation in vivo as well as regulation of transcription of various genomic features including gene bodies, germline genes and transposons. In Aim 2, will test the ability of Dnmt3b to complex with other Dnmts and contribute to de novo methylation induced by other Dnmts in Dnmt1-/-;Dnmt3a-/-;Dnmt3b-/- triple knockout mouse embryonic stem cells. In addition, we will genetically test the importance of Dnmt3a and Dnmt3l for Dnmt3b’s accessory function and validate our data in a human cell line. In Aim 3, we will perform longitudinal study of Dnmt3b+/+ and Dnmt3bCI/CI mice conceived through the use of in vitro fertilization (IVF) technique to analyze disease development, Dnmt levels, the rate of methylation and gene expression errors, as well as their persistence over time. Collectively, our studies will reveal physiological relevance of Dnmt3b activities in mouse development, uncover basic mechanisms utilizing Dnmt3b functions and their involvement in IVF. Our results could result in changes in Assisted Reproductive Technologies (ART) and affect the focus of preventive care for ART- conceived individuals.

NIH Research Projects · FY 2026 · 2022-06

PROJECT SUMMARY The overall objective of this proposal is to infuse clinical inspired design throughout a biomedical engineering curriculum. We propose to develop a summer clinical immersion program based on the value of multi- disciplinary input and interactive student mentoring in problem finding. Deliverables from the summer experience will impact courses throughout the curriculum by providing open-ended, problem-based case studies that will engage aspects of design thinking and application of specific course material. The summer experience will also seed projects for a senior design course, focused on the creation of medical device prototypes and skills development that emphasize multidisciplinary communication. To promote co-learning and the further integration of design across the curriculum, senior student teams will apply their learning to lead workshop activities in other classes. This will serve to connect different level thinkers and experiences across student cohorts. The proposed project has strong enthusiasm and commitment from established partnerships between biomedical engineering faculty, clinicians in the College of Medicine, clinicians in the College of Veterinary Medicine, industry leaders, and administration. Our goal is to emphasize translational opportunities throughout the maturation of novice problem solvers to open-ended decision makers. Specifically, the new summer clinical immersion experience will bi-directionally integrate the value of design thinking across the department through the completion of the following inter-related aims: Aim 1: To develop and implement a summer clinical immersion program with multi-disciplinary input and enhanced student interaction. Aim 2: To seed fundamental biomedical engineering courses across the curriculum with clinically inspired design problems. Aim 3: To facilitate bidirectional co-learning to enhance the senior design and entire biomedical engineering curriculum. Biomedical engineering at UF is primed to make the proposed jump in design education based on over 40 established relationships with clinicians, the existing engagement of 13 industry partners, and a developing curriculum that makes design integration possible. The proposed course and programmatic innovations will provide a curriculum model that can be disseminated to other departments with the overall goal of enhancing biomedical engineering design education to ensure students self-identity as clinical translators.

NIH Research Projects · FY 2026 · 2022-06

Project Summary/Abstract. Mobility disability impacts approximately 30% of individuals aged 60-69, 40% of individuals aged 70-79, and 55% of individuals age 80 or older. Emerging cross-sectional evidence suggests that self-reported musculoskeletal pain may be one of the major drivers of age-related mobility decline. Despite this evidence, significant knowledge gaps remain because the relationships among chronic musculoskeletal pain, aging, mobility, psychosocial function, and the brain have not been studied longitudinally in the same older individuals. Our prospective study design will provide novel information on the role of pain-related brain changes as predictive factors of age-related mobility decline. The proposed work will allow us to determine whether pain as well as brain structure and function predict mobility decline longitudinally (Aim 1) and whether brain measures mediate the pain-mobility association prospectively (Aim 2). Findings may support the value of incorporating pain’s impact on the brain into treatments that target mobility decline in aging. The proposed work integrates multiple fields of study within a biopsychosocial approach to study pain and mobility in the older population.

NIH Research Projects · FY 2026 · 2022-05

Summary: Steroid hormones receptors (SR) are ligand-dependent nuclear transcription factors that exhibit remarkable functional diversity in mediating cell/tissue and target gene specific responses, largely driven by conformational dynamics of the SR protein that enables it's binding of unique subsets of transcriptional co- regulatory proteins (CoRs) and DNA response elements. The progesterone receptor (PR) is the main target of progestogens that are widely used clinically. PR is expressed as two protein isoforms, an N-terminal truncated PR-A and full-length PR-B and each have distinct physiological roles dependent on the cell/tissue type. In general PR-A is a weaker transcriptional activator than PR-B, and can act to attenuate the activity of PR-B. Both isoforms are typically co-expressed in equal proportions in most normal tissues. However, PR-A to PR-B ratios have been reported to be highly variable in pathological conditions. Mechanistic basis for differences in activity of the isoforms is not well defined but is generally believed to be due to unknown differences in structural conformations. Thus, to fully understand PRs' biology requires determination of a high-resolution structure of the full-length PR isoforms and associated CoRs as a complex on target DNA and an understanding of how protein interactions within the complex and structural conformations affect activity of PR. The conformational flexibility of SRs and CoRs, coupled and their large sizes (100–300 MW), make them unsuitable to either high resolution NMR or X-ray crystallography analysis. As an alternative, this proposal will integrate complementary solution- phase techniques to determine high-resolution 3D structural models and uncover the conformational dynamics within the PR:CoR/DNA complex. Recent advances in Cryo-EM enable the determination of solution-phase structures of large conformationally heterogenous macromolecular complexes at subnanometer resolution. We will combine Cryo-EM with crosslinking mass spectrometry (XL-MS) to further refine structural Cryo-EM models and assure high resolution and with hydrogen-deuterium exchange (HDX) to map conformational dynamics and allostery within the PR:CoR/DNA complex. The overall goal of this project is to determine the highest resolution 3D structure possible of full-length PR-A and PR-B in complex with classical CoRs and novel CoRs on PR DNA response elements. Aim 1 will utilize Cryo-EM to analyze the structural features of PR-A and PR-B in complex with the classical CoRs SRC3 and p300 and with the novel CoRs TBP and JDP2 assembled on target DNA. Aim 2 will refine the Cryo-EM structure of PR:CoR/DNA complex using integrated structural modeling and XL- MS to define distance constraints and probe conformational dynamics within the PR complex by differential HDX. Aim 3 will perform functional mutagenesis studies to determine the influence of PR:SRC3/p300 interaction surfaces revealed in structural models and from XL-MS data have on PR activity. The impact of this proposal will be to fill a major gap in our understanding of the structure and conformational dynamics of the PR:CoR/DNA complex. These studies could open opportunities for novel studies of drug interactions at the atomic level.

NIH Research Projects · FY 2025 · 2022-05

Project Summary A critical step in the success of adoptive cell transfer (ACT) T cell immunotherapy in solid cancers is achieving trafficking and persistence of T cells at tumor sites, while avoiding toxicities due to T cell attack of off-target tissues and organs. Non-invasive quantitative imaging would be a powerful tool to understand mechanisms of action and failure of T cell immunotherapies, evaluate the impact of T cell modifications and delivery routes, monitor off-target T cell accumulation, and stratify response to therapy on the basis of measures of T cell tumor accumulation. This Bioengineering Research Grant project will pioneer non-invasive and quantitative tracking of adoptive T cell cancer immunotherapy using magnetic particle imaging (MPI), a new molecular imaging modality that enables non-invasive, unambiguous, and tomographic analysis of the whole-body distribution of superparamagnetic iron oxide nanoparticles (SPIONs). Preliminary results demonstrate non-invasive quantitative tracking of ACT T cells in solid intracranial tumors, synthesis of tracers with enhanced MPI sensitivity, and current sensitivity of 5x103 T cells. The proposed work aims to improve sensitivity to 5x102 T cells and demonstrate the accuracy of MPI in quantifying T cell biodistribution in mouse models of cancer. Modeling of MPI physics by the PI demonstrates that tracers optimal for MPI must have uniform physical and magnetic properties and low magnetocrystalline anisotropy, to enable fast dipole switching at large SPION diameters. The PI has developed a new synthesis that yields defect-free SPIONs with uniform magnetic properties and low magnetocrystalline anisotropy. The proposed work (Aim 1) will couple this new synthesis with modeling of MPI physics and comprehensive physical and magnetic characterization to gain fundamental understanding of the relation between SPION properties and MPI performance and to obtain SPIONs with superior sensitivity. Imaging approaches to track T cells must not compromise their viability or function and T cells pose unique challenges for nanoparticle labeling. The proposed work (Aim 2) will define an upper limit for labeling primary T cells with MPI tracers without compromising viability or function using tracers that associate with T cells through charge interactions. Preliminary studies demonstrate non-invasive tracking of T cell biodistribution in mice using MPI, and that SPION-labeled T cells reach solid tumors after systemic administration in murine models. The proposed work (Aim 3) will validate in vivo tracking of ACT T cell therapy using MPI against T cell counting using flow cytometry and will evaluate dynamics of T cell accumulation in tumors longitudinally using MPI. The proposed biomaterials-development research plan is enabled by the complementary expertise of the PI (SPIONs and MPI physics) and Co-I (ACT T cell therapies) and access to state-of-the-art instrumentation to characterize SPION MPI performance ex vivo and in vivo. Achieving the target sensitivity of 5x102 T cells will provide an order-of- magnitude improvement in quantitative cell tracking sensitivity over other whole body quantitative imaging technologies, establishing MPI as a powerful tool in the immunoimaging toolbox.

NIH Research Projects · FY 2026 · 2022-05

PROJECT SUMMARY/ABSTRACT Physical frailty (hereafter simplified to “frailty”) refers to a clinical state associated with an individual’s increased risk of dependence or mortality when exposed to a stressor and has emerged as a major predictor of poor health outcomes in the elderly. Unfortunately, the mechanisms contributing to the exacerbation of normal aging that precipitates frailty are largely unknown. In this regard, recent epidemiological studies find that elevated circulating levels of kynurenine, a product of tryptophan metabolism that accumulates in blood with aging, strongly associate with poor physical function and elevated risk of frailty. However, a causal relationship between elevated kynurenine and poor physical function/frailty has not been tested. Our preliminary data show that kynurenine causes atrophy and impaired mitochondrial function in skeletal muscle cells that can be rescued by increasing the capacity for kynurenine biotransformation into the neuroprotective metabolite, kynurenic acid. Since kynurenine is also an agonist of the ligand-activated transcription factor known as the aryl hydrocarbon receptor (AHR), it is noteworthy that we find that transcripts regulated by the AHR are upregulated in aging muscle, and that AHR knockdown blunts kynurenine-induced mitochondrial dysfunction. Finally, we also show that chronic AHR activity alone is sufficient to induce atrophy, mitochondrial dysfunction and neuromuscular junction degeneration in young mice, which are hallmarks of aging that are exacerbated in frailty. On this basis, the first goal of this project is to determine if elevated kynurenine levels accelerate the physical function decline and frailty with aging in mice. Secondly, we will determine if enhancing kynurenine metabolism attenuates the decline of physical function and frailty with aging in mice, with or without elevated kynurenine. Thirdly, we will test if knockout of the AHR attenuates the decline of physical function and frailty with aging in mice, with or without elevated kynurenine. Finally, we will test if chronic AHR activity in muscle alone is sufficient to accelerate physical function decline and frailty with aging in mice. By doing so, our studies will lay the foundation for future testing of therapies that augment kynurenine metabolism and/or inhibit the AHR as a means of attenuating frailty with aging.

NIH Research Projects · FY 2026 · 2022-04

There is no licensed vaccine for humans against potentially life-threatening paratyphoid and nontyphoidal septicemia caused by the Salmonella enterica. This intracellular pathogen evades sophisticated host immune defenses. The host immune system is controlled by regulatory mechanisms, such as intercellular communication between infected and uninfected cells, which can also be accomplished via small extracellular vesicles (EVs), exosomes. Exosomes are vesicles that originate in the endosomal pathway and transport cargo to other cells. We found that exosomes carry bacterial antigens (Ags) from S. Typhimurium-infected macrophages ( MΦ s) and stimulate naïve antigen-presenting cells involved in T cell recruitment, and an intranasal administration of these exosomes leads to the production of anti-S. Typhimurium antibodies (Abs) and stimulation of Th 1 response critical for engulfing and killing intracellular bacteria. These adaptive responses are Ags-dependent, but the Ags responsible for this humoral response or the mechanisms responsible for Ag trafficking to EVs are unknown. We will address the contribution of exosomes to adaptive immune responses against intracellular pathogens as there is a critical need to determine new mechanisms of protective immune responses, such as exosome-modulated immunity. Our long-term goal is to advance the development of mechanism-based preventative measures for bacterial infections. Our overall objective is to elucidate the mechanisms whereby bacterial Ags are trafficked to exosomes and identify the capability of exosomes to generate protective cellular and humoral immunity against intracellular Salmonella. Our central hypothesis is that Salmonella Ags are trafficked to endosomal compartments of infected MΦs and released via exosomes to stimulate innate responses and Ag-specific Th1 cell responses . The rationale is that determining the mechanisms via which Salmonella Ags are trafficked to exosomes and generate adaptive immunity against Salmonella, we will assign a novel role of EVs in host defense, important for the design of preventative approaches. In Aim 1, we will identify mechanisms whereby Salmonella Ags are trafficked into EVs. In Aim 2, we will determine the mechanisms by which EVs produced by Salmonella-infected determine how EVs MΦ s regulate the activation and function of DCs in mucosal tissues. In Aim 3, we will derived from Salmonella-infected MΦ s drive adaptive immunity. The expected outcomes are that we will have established a mechanism responsible for the trafficking of Ags into EVs, and characterize novel roles of EVs in innate immunity and Th1 adaptive immunity. This study will have a positive impact as it will provide a conceptual framework for the future development of targets for vaccine design and significantly advance knowledge of how Salmonella disrupts host immunity, which is vital for the development of preventative and therapeutic approaches against this pathogen. The innovation lies in addressing the function of EVs produced by host cells in rendering protection against salmonellosis. This study is significant since we will advance knowledge on the function of host exosomes in altering the immune response to Salmonella infection.

NIH Research Projects · FY 2024 · 2022-04

Summary Autism spectrum disorder (ASD) is a neurodevelopmental disorder with deficits in two core domains: social interaction and communication, and repetitive behaviors or restrictive behaviors. It is diagnosed four times more frequently in boys than in girls. Among a large number of risk loci for ASD, elevated protein synthesis has been recognized as a converging pathological mechanism. ASD is associated with a high percentage of patients with inactivating mutations in genes for several negative translation regulators, such as PTEN, TSC1, TSC2 and FMR1. These mutations increase the availability of eukaryotic translation initiation factor 4E (eIF4E), consequently elevating translation of a selective group of mRNAs. However, it remains unknown in which type of brain cells and how elevated translation leads to dysfunction of neural circuits and subsequently ASD behaviors. We have generated a knock-in mouse strain in which eIF4E is overexpressed from the Rosa26 locus in a Cre-dependent manner. We found that eIF4E overexpression in microglia, but not neurons or astrocytes, led to ASD-like synaptic and behavioral aberrations only in male mice, including increased dendritic spine density, excitation/inhibition imbalance, social interaction impairment, increased repetitive behavior, and selective cognitive deficits. We further found that microglial eIF4E overexpression elevated translation in both sexes but only increased microglial density and size in males. Given critical roles of microglia in synapse development, we posit that elevated synthesis of some proteins alters microglial functions only in male mice, which in turn impairs synapse development and thereby male-biased ASD. We will test this hypothesis in the following three specific aims. Aim 1 is to investigate the molecular mechanism by which elevated protein synthesis alters microglia; Aim 2 is to understand the mechanism underlying the sexual dimorphism of ASD- like phenotypes in MG4E mice; Aim 3 is to determine how microglial alterations impact synapse development by imaging in vivo dynamics of dendritic spines and microglia in control and MG4E mice. This research project will not only provide insights into the pathological mechanism by which mutations in negative translation regulators lead to ASD, but also show microglial dysfunction as a possible etiology of ASD. It may also uncover a mechanism that underlies the strong male bias of ASD, which could guide strategies for innovative therapies of the disorder.

NIH Research Projects · FY 2025 · 2022-04

Project Summary There is an urgent need for development of metabolic imaging methods that are sensitive to nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), and to the transition linking the two pathophysiological states. We will develop magnetic resonance based metabolic imaging using hyperpolarized 13C and thermally polarized 2H-labeled substrates. Our testbed is the C57Bl/6N mouse, and diet induced and genetic models of the disease states. The approach assays both carbohydrate and fatty acid metabolism, which are known to be altered in these diseases. Aim 1. Using hyperpolarized [1-13C] and [2-13C]pyruvate and [2-13C]dihydroxyacetone, we will produce a multi-parametric assessment of hepatic pyruvate oxidation and anaplerosis, as well as pyruvate cycling. Aim 2. Using uniformly deuterated fatty acids, we will determine rates of β-oxidation and changes in redox biology in the same models. The combination of these approaches will yield the most comprehensive analysis of energy metabolism to date in these well-accepted models of the human disease. Aim 3. We will confirm both carbohydrate and fatty acid metabolism imaging assays using knock out mice that test the assumptions underlying our paradigms. The pyruvate carboxylase knockout mouse downregulates pyruvate anaplerosis. The fumarate hydratase knockout mouse is a model of downregulated metabolism that will test our sensitivity to changes in Krebs cycle turnover. The acetyl-CoA carboxylase knockout mouse will upregulate fatty acid oxidation. All three pathways have been hypothesized as essential elements of the pathogenesis and progression of NAFLD and NASH. Relevance NAFLD and NASH are now a worldwide epidemic, with some estimates of NAFLD prevalence as high as 24% of the world population. NASH is expected to surpass hepatitis as the number one cause of liver transplant in the United States within the next 5 years. Over the next 10 years, this disease is projected to be a 1 trillion dollar burden to the healthcare system. While imaging of fibrosis is somewhat diagnostic of NASH progression, there is no metabolic imaging technique that is sensitive to the inflammation endemic to the transition of NAFLD to NASH. Current stepwise paradigms for identifying NASH lack the sensitivity to correctly classify early development. When NASH is diagnosed, clinical management of the disease changes dramatically, becoming much more expensive. Development of a metabolic imaging method for diagnosis and staging of NASH would significantly enhance healthcare practice, with prospects for improving patient care and decreasing costs.

NIH Research Projects · FY 2026 · 2022-04

PROJECT SUMMARY Individuals with thumb carpometacarpal osteoarthritis (CMC OA) can lose up to 50% of hand function. Unfortunately, current conservative and surgical treatments do not provide the pain relief, strength, and mobility needed to restore both fine and gross motor function. Improvements in clinical treatments are limited by a lack of understanding regarding the complex relationship between thumb biomechanics and musculoskeletal pain. In this proposal, we address this critical knowledge gap by examining the role of thumb muscles in modulating the two primary symptoms of CMC OA: pain and joint instability. Individuals across the full spectrum of disease severity and healthy controls will be studied to evaluate individuals who present with only joint instability, only pain, both, or neither. In Aim 1, to what extent muscle structure changes in the presence of CMC OA and how these changes affect muscle force-generating capacity will be evaluated. Collected data will include fascicle length and cross-section area measured in vivo through ultrasound imaging and thumb muscle operating ranges calculated through musculoskeletal simulations. Completion of this aim will identify changes in muscle structure that mitigate versus aggravate CMC OA symptoms and also establish baseline data describing healthy targets for thumb muscle force-generating parameters. In Aim 2, how thumb muscle activity influences pain will be examined through an experiment that integrates biomechanical techniques (e.g., electromyography) and quantitative pain testing (e.g., movement-evoked pain, quantitative sensory testing). Completion of this aim will enhance our understanding the relationship between muscle activity and pain, thereby elucidating protective versus detrimental compensatory movement strategies adopted by individuals with CMC OA. In Aim 3, how thumb muscle activity influences joint stability will be examined. Collected data will include experimental measurements of muscle activity, thumb kinematics, and thumb kinetics during functional and range of motion tasks as well as biomechanical assessments of joint instability in the presence of active versus passive muscle contraction. Completion of this aim will identify how CMC OA and muscle activity influences CMC joint stability, thereby informing clinical decisions regarding how muscles should (or should not) be considered during CMC OA treatment. Overall, this study will critically advance our mechanistic understanding of how the structure and function of thumb muscles change in the presence of CMC OA. By evaluating muscle mechanics (Aim 1), pain (Aim 2), and joint stability (Aim 3) in individuals with and without CMC OA, we will elucidate the co-evolution of muscle mechanics, symptom severity, and disease severity. This knowledge will inform current and future treatment of CMC OA, thereby improving the quality of life of individuals living with this disease.

NIH Research Projects · FY 2026 · 2022-04

Project Summary In osteoarthritis (OA), intra-articular inflammation is a key mediator of joint destruction and chronic joint pain. Unfortunately, current strategies to control joint inflammation have largely failed. To address this challenge, our team is developing an innovative metabolic reprogramming strategy for the treatment of knee OA. In our strategy, indoleamine 2,3-dioxygenase (IDO), an immunosupressive enzyme, will be intra-articularly delivered to catabolize tryptophan into kynurenines. Based on IDO’s effect in other tissues, this redirection of tryptophan metabolism will likely drive the polarization of joint-level immune cells toward an anti-inflammatory state. Importantly, our strategy differs from other intra-articular delivery strategies for protein and synthetic drugs, as our enzyme will continuously produce anti-inflammatory metabolites in the OA-affected joint and thereby create prolonged anti-inflammatory effects that potentially reset immune homeostasis in the joint. However, while IDO can continuously produce anti-inflammatory metabolites, free IDO is subject to joint clearance. To address this challenge, we will also fuse IDO to a carbohydrate-binding protein, thereby extending IDO’s joint residence time via a novel tissue anchoring approach. Morever, because tissue-anchored IDO does not need to release to generate anti-inflammatory signals, the anchored IDO will continue to produce anti-inflammatory kyneurenines without the need for our ‘drug’ (IDO) to release and bind a specific target. Our preliminary data demonstrate that tryptophan metabolism is altered in both human OA and rodent models, our tissue anchoring strategy can extend the residence time of an enzyme from a few days to over 4 weeks, and that intra-articular delivery of an IDO fusion protein can shift tryptophan metabolism, reduce inflammation, and reverse pain-related behaviors in a rat knee OA model. As such, this R01 proposal seeks to evaluate intra-articular delivery of an IDO fusion protein as a therapeutic strategy to control joint inflammation and reduce OA-related pathological remodeling after trauma (Aim 1) and after the onset of chronic OA symptoms (Aim 2). To achieve these aims, our team will integrate expertise in metabolic profiling, immune engineering, joint histology, and rodent behavioral analyses. Specifically, this R01 will address the following scientific questions: 1) How is joint metabolism altered by intra- articular delivery of an IDO fusion protein? 2) How is the local regulation of the immune system within the joint altered by an intra-articular injection of an IDO fusion protein? 3) Do IDO-induced metabolic shifts affect other joint tissues as well? 4) Can intra-articular injection of an IDO fusion protein stall the onset of post-traumatic OA after medial meniscus injury? and, 5) Can intra-articular delivery of an IDO fusion protein reverse OA-related pain and disability, even in the context of irreparable joint damage? Answering these questions will be important for understanding the translational risks of our IDO fusion protein, as well as for refining metabolic reprogramming strategies for OA treatment in the future.

NIH Research Projects · FY 2025 · 2022-04

ABSTRACT Neonatal sepsis results in more than 3 million deaths per annum worldwide and the highest risk of mortality occurs in preterm infants (≤37 weeks). This increased vulnerability is due to altered myelopoiesis and an intrinsic hypo-responsiveness to pathogens, concomitant with activation of immunosuppressive mechanisms that sustain maternal-fetal tolerance. Following birth, the neonatal immune system undergoes transition from a semi- allogeneic sterile condition to a microbial-rich postnatal environment, which is modulated in part by neonatal myeloid-derived suppressor cell (MDSC) and innate immune effector cell responses. In newborns, the role of MDSCs is highly controversial, as they may not only control inflammation during early microbial colonization, but also contribute to neonatal susceptibility to infection by inducing immunosuppression. Innate immune effector cell function is also aberrant in prematurity. Our overarching hypothesis is that the increased susceptibility to and mortality from sepsis in preterm neonates can be explained in part by the presence of immature, immunosuppressive myeloid cell populations (MDSCs) and deviant terminal differentiation of innate immune effector cells (e.g. monocytes, PMNs). Furthermore, we propose that the prophylactic administration of immunomodulatory agents early in life can stimulate host protective immunity by altering MDSC numbers and function, leading to augmentation of innate immune effector cell numbers and function (especially PMNs). This strategy will reduce the incidence and severity of microbial infections in this fragile ‘born-too-soon’ population. The two specific aims are as follows: (1) to test the hypothesis that neonatal prematurity and sepsis in early life induce MDSC expansion, which is inversely correlated with innate immune cell function. Circulating MDSCs (CD33+CD11b+HLADRlow/-) will be quantified in 120 preterm and 40 full-term infants at birth and during hospitalization and in those who develop sepsis. We will determine how human MDSC and PMN phenotypes are influenced by gestational age and sepsis, as well as whether expansion of MDSCs and PMN dysfunction at birth is beneficial or increases susceptibility to infections. (2) In complimentary studies that cannot be performed in humans, we hypothesize that myelopoiesis and myeloid function (especially MDSCs) can be influenced to differentiate into functional terminal innate immune effector cells by the administration of immunomodulatory agents. Using a model of neonatal sepsis, we will test the role of MDSCs in immune cell effector functions and outcomes to sepsis through the induction of non-specific effects (NSEs) or ‘trained immunity’. In summary, the proposed studies will focus on mechanisms critical to regulate neonatal immune responses in neonates. With the use of -omics technology, we expect to provide: 1) a global view of changes that myeloid populations undergo in preterm neonates during hospitalization and sepsis, and 2) insights into underlying mechanisms of how immunomodulation through the use of adjuvants (BCG and TLR4 agonists) influences myeloid cells and prevents sepsis in this highly vulnerable population.

NIH Research Projects · FY 2025 · 2022-04

PROJECT SUMMARY / ABSTRACT The objective of this project is to induce localized immune tolerance to transplanted human beta cells derived from renewable stem cell sources as a treatment for type 1 diabetes. We will test our approach to prevent immune rejection of grafted human stem cell derived beta cells in diabetic mice with elements of human immune systems. In addition, we seek to explain the detailed biological mechanisms by which the therapy works by conducting in vitro studies using islet- reactive human T cells. Recent advances in the generation of stem cell derived beta-like cells (sBCs) have raised the possibility of providing a renewable source of functional beta cells for transplantation, effectively overcoming the severe shortage of human donor islets. We have generated simplified culture conditions that accurately and efficiently generate unlimited quantities of glucose-responsive insulin-expressing beta cells in vitro. The stem cell derived beta cells generated have already been used successfully for beta cell replacement therapy in animal models. By combining cell engineering with biomaterials engineering to display negative regulators of immunity (e.g. programmed death-ligand 1, PD-L1; and tumor necrosis factor (TNF)- related apoptosis-inducing ligand, TRAIL), we will functionalize stem cell derived beta cells (sBCs) to counter autoimmunity upon transplantation. A major strength of our approach is that the immunotherapy is strongly localized to grafted beta cells, which increases specificity and avoids the negative side effects of systemic immunotherapy. We hypothesize that stem cell derived human pseudo islets transplanted with PD-L1 and/or TRAIL will be resistant to autoimmune destruction and exhibit enhanced engraftment / survival in an in vivo model of beta cell graft rejection using humanized mice. Our strategy will induce localized tolerance to beta cell antigens while simultaneously promoting sBC graft vascularization.

NIH Research Projects · FY 2026 · 2022-04

Project Summary Fatty fibrosis, the replacement of healthy muscle tissue with fat and fibrotic scar tissue, is a prominent feature of chronic muscle diseases such as Duchenne muscular dystrophy (DMD), sarcopenia, the age-related loss of skeletal muscle and strength, in addition to obesity, and diabetes. This project will identify and characterize the cellular and molecular mechanisms by which intramuscular fat forms, and the functional consequences of intramuscular fat on muscle health. Recent evidence points to ciliary Hedgehog signaling as a potent ant- adipogenic signal during muscle regeneration and in mdx mice, a mouse model of DMD. In addition, Hedgehog promotes muscle repair and prevents the decline in myofiber size in mdx mice. By what mechanism(s) Hedgehog acts to balance fat formation and muscle regeneration is unknown. This proposal will use innovative and powerful mouse models to identify the role of Hedgehog signaling during muscle regeneration in the following aims: 1) Identify and characterize the responsible Hedgehog ligand; 2) determine which cell types respond to Hedgehog signaling; and 3) demonstrate if intramuscular fat directly affects muscle health. Taken together, this proposal will provide insights into the origin and function of intramuscular fat and will aid in the search for novel therapeutic interventions into human diseases affected by fatty fibrosis.

NIH Research Projects · FY 2022 · 2022-04

People living with HIV (PLWH), even with anti-retroviral therapy (ART), have an accelerated and augmented onset of non-AIDS related diseases such as the premature development of cardiovascular disease (CVD). In fact, CVD has become the second most common cause of non-AIDS related mortality in PLWH in the US. Herein, we aim to decipher the underlying mechanism for HIV-associated CVD. Specifically, our focus is on the bone marrow-blood (BMB) barrier and stem cell niche, as a vulnerable microenvironment that regulates the immune status in CVD. The bone marrow (BM) is an important reservoir for hematopoietic stem cells (HSCs), which give rise to immune cells including circulatory monocytes (inflammatory vs non-inflammatory). Recent studies have highlighted the importance of vasculature permeability (or lack thereof) in controlling HSC differentiation. Additionally, areas of the vasculature in the BM niches responsible for maintaining the long-term HSCs exhibit restrictive permeability properties (regulated by pericytes) similar to that of the blood-brain barrier. While the effect of HIV infection in the BM in the era of ART is unknown, it may mirror what is observed in the brain. Of note, it is well established that HIV infection and inflammation in the brain leads to reduced pericyte coverage and increased vascular permeability. Epidemiological studies indicate that comorbid substance use disorder is common in PLWH. Furthermore, drugs of abuse are well documented in exacerbating HIV pathology. For example, chronic cocaine use independently increases CVD risk and further augments its development in PLWH, highlighting a synergistic link between HIV infection and cocaine use. We propose that increased BM vascular disruption and reduced pericyte coverage resulting from HIV infection and cocaine could alter the balance of HSC differentiation and drive the underlying chronic immune activation which advances CVD progression. Thus, our hypothesis is that HIV and cocaine induce BMB barrier dysfunction which skews HSCs towards differentiation and production of inflammatory monocytes that promote early CVD. The study of dysfunctional BM microenvironments has never been examined as a factor in CVD during HIV infection/drug use. Our approach is highly conceptually and technically innovative and would be the first to study changes in the BMB barrier. This hypothesis will be examined using tissue clearing, microCT and advanced imaging techniques to map the 3D vascular architecture in humanized HIV-infected mice. Finally, we propose to develop a new human 3D tissue engineered model of the BM vasculature for the study of HIV pathogenesis. In brief, chronic immune activation is considered the leading factor driving early CVD in HIV+/chronic cocaine users; however, the underlying cause remains unknown. Therefore, identifying the mechanism of immune activation could lead to targeted treatment of HIV+ patients/drug users and management strategies to slow or prevent plaque development. These studies fit within the framework of the Avenir DP2 program to encourage early-stage investigators to pursue bold ideas with innovative approaches.

NIH Research Projects · FY 2025 · 2022-04

Project Summary/Abstract Many different disease states and surgical interventions result in a period of inadequate tissue/organ blood supply (i.e., ischemia), that result in reperfusion injury when blood flow is restored, known as ischemia-reperfusion injury (IRI). IRI causes local inflammation, cell death, excessive tissue destruction and possible organ failure. Examples are found in transplantation, trauma, myocardial infarction, stroke, and in particular, IRI is a main cause of liver dysfunction and failure after liver surgery. Unfortunately, there are currently no therapies available in clinical practice addressing IRI, where a major problem is the harmful systemic side effects and toxicities of existing drugs. To address this problem, we are innovating a new therapeutic technology aiming to program immune cells toward a metabolic state blocking excessive inflammation by directing tryptophan metabolism through delivery of an enzyme into circulation. This represents a new class of anti- inflammatory/immunosuppressive biologic drug, with potential to limit systemic toxicities/side effects, and with potential to be significantly less immunocompromising. Lack of treatment options for liver IRI and a catalog of in vivo preliminary data strongly supporting the foundational rationale of IDO as an innovative new anti-inflammatory agent, make this proposal highly significant. Looking to the future, success would open opportunity to expand to other anti-inflammatory applications, for example, pre-conditioning donor grafts for transplantation.

NIH Research Projects · FY 2025 · 2022-03

Project Summary/Abstract American Indians (AIs) have the highest prevalence of type 2 diabetes (T2D) of any racial or ethnic group and experience high rates of co-morbidities such as obesity, cardiovascular disease (CVD), and chronic kidney disease (CKD). Uncontrolled cardio-metabolic risk factors--insulin resistance resulting in impaired glucose tolerance, dyslipidemia, and hypertension (HTN)--increase mortality risk. Mortality is significantly reduced by glucose- and lipid-lowering, and antihypertensive medication adherence. Medication adherence is low among AIs living in non-Indian Health Services (IHS) healthcare settings. Virtually nothing is known about the nature and extent of medication adherence among reservation-dwelling AIs who primarily receive their medications without cost from IHS/tribal facilities. Electronic health records (EHR) offer a rich but underutilized data source about medication adherence and its potential to predict Cardio-Metabolic Control Indicators (C-MCI) such as HbA1c, LDL-C (Low Density Lipoprotein), SBP (Systolic Blood Pressure). With the support of Choctaw Nation of Oklahoma (CNO), we will address this oversight by using EHR data generated by this large, state-of- the-art tribal healthcare system to investigate C-MCI. The objective of our R01 application is to characterize the relationships among medication adherence (antihypertensive, glucose- and lipid-lowering drugs) and C- MCI (HbA1c ≤7%, LDL-C <100 mg/dL, and SBP <130 mm Hg), patient demographics (e.g., age, sex, SDOH, residence location) and co-morbidities (e.g., CVD, BMI>30, CKD) as well as the relationship of each C-MCI with patient demographics and co-morbidities from the tribe's EHR (2018-2021) for the 5,970 CNO patients who have T2D. Employing machine learning techniques, we will develop models to predict future (2019-2021) C-MCI based on the previous year medication adherence, patient demographics, co- morbidities, and common labs (e.g., lipid panel). Lastly, key informant interviews will explore facilitators of and barriers to medication adherence within the context of local social determinants of health (SDOH) that are not available in the EHR. Our specific aims are to: (1) Determine the bivariate relationships between (a) medication adherence and C-MCIs, demographics, and co-morbidities; (b) each C-MCI and demographics and co-morbidities; (2) Develop machine-learning models (e.g., random forest, nearest neighbors, others) for predicting future (2019-2021) C-MCI from the previous year medication adherence, demographics, co- morbidities, and common labs; and (3) Identify facilitators of and barriers to medication adherence within the context of SDOH, EHR-derived medication adherence (PDC) and C-MCI (at target, above target, and for HbA1c uncontrolled). We will share our findings with CNO leaders and other stakeholders, who will guide the translation of the results into recommendations for evaluating T2D management and complication prevention programs. Our findings will yield insights to improve medication adherence and C-MCI among AIs, consistent with CNO's State of the Nation's Health Report 2017 goal of reducing T2D and its complications.

NIH Research Projects · FY 2026 · 2022-03

Project Summary. Much of human interaction is based on trust. Aging has been associated with deficits in trust- related decision making, likely further exacerbated in age-associated neurodegenerative disease (Alzheimer's disease/AD), possibly underlying the dramatically growing public health problem of elder fraud. Optimal trust- related decision making and avoiding exploitation require the ability to learn about the trustworthiness of social partners across multiple interactions, but the role that learning plays in determining age deficits in trust decisions is currently unknown. To address this gap, this project will (i) characterize basic cognitive processes and neural mechanisms in learning to trust and distrust in healthy aging and in older individuals with subjective cognitive decline (SCD) and a family history of AD, representing an `early' preclinical AD group; and (ii) probe the malleability of these processes with training to form the foundation for future clinical intervention toward reducing exploitation vulnerability in aging. The proposed work is conceptually embedded in the Changes in Integration for Social Decisions in Aging (CISDA) framework. This framework describes how the integration of decision- relevant information is impacted by trajectories of change in theory of mind, memory systems, and social- emotional processing with age. Two innovative trust-learning paradigms – the Social Iowa Gambling Task (sIGT) and the FLorida-Arizona Gambling Task (FLAG) – will be leveraged to test CISDA predictions across three experiments and complimented by an ecologically valid transfer task assessing elder fraud susceptibility. The proposed research addresses three goals. Aim 1/Study 1: Confirm age deficits in learning to trust in an adult lifespan sample that also includes older individuals with SCD and determine the extent to which social cues of trustworthiness bias trust-related decisions and learning in older age and individuals with SCD. Further, this study will use computational modeling to isolate specific learning biases (social cue, loss aversion, and recency) within the CISDA framework. Aim 2/Study 2: Use fMRI versions of the two new learning paradigms to confirm altered anterior cingulate cortex, insula, and amygdala activity, and their interplay, as neural mechanisms of age- associated learning deficits. Aim 3/Study 3: Probe the malleability of the underlying neurocircuitry of trust- learning deficits in aging. This study will utilize real-time fMRI neurofeedback to train healthy older adults in anterior cingulate cortex up-regulation toward enhanced trust-related learning in aging and confirm critical mechanisms of experience-dependent social decisions in aging. This project's interdisciplinary approach encompasses experimental and affective aging, neuroeconomics, and computational neuroscience. Collectively, this research will advance the basic science of social decision making in aging and determine the malleability of underlying neurocircuitry to inform decision-supportive intervention targeted at optimizing trust-related decision making and reducing exploitation in the elderly.

NIH Research Projects · FY 2026 · 2022-02

ABSTRACT Older adults represent a fast-growing segment of medical marijuana (MM) users in this country, with chronic pain as the most cited reason for use. There is a critical need to systematically examine MM’s short- and long- term effects on the core outcomes including pain intensity, physical, emotional, and cognitive functioning, and overall quality of life, and to track its side effects in older adults (NOT-DA-20-014). While the ubiquity of mobile technology provides a unique opportunity to measure MM use and its outcomes in vivo, it has not been applied in MM and pain research. In addition, our research shows that telomere length, a measure of cellular aging, is negatively associated with chronic pain stage, but no study has used telomere length as a biomarker to examine MM’s long-term effects on biological aging in older adults. Further, while contributing to the differentiated response to MM, individual differences (e.g., sex, baseline pain phenotyping, expectancy) have not been adequately explored in prior research. To address these gaps, we propose the first prospective cohort study that innovatively combines technology-based ecological momentary assessments (EMA) and in- person visits over 12 months to obtain both subjective and objective data on MM’s effects. The main goals of this project are to 1) determine MM’s short- and long-term effects on pain, physical, emotional, and cognitive functioning, and quality of life in older adults, and 2) identify MM product characteristics and patient subgroups associated with improved outcomes or side effects. To accomplish these goals, we will recruit and follow 440 older adults (³ 50 years, 50% male) with chronic pain as some initiate MM (n=330) and other do not (n=110). Subjective and objective data will be collected at in-person visits (baseline & 12 months) and via smartphone- and sensor-based measurement bursts at 1, 3, 6, and 9 months. The specific aims are: 1) Determine whether MM use leads to short-term changes in pain intensity level, physical and emotional functioning measured in real-time; 2) Determine whether MM use leads to longer-term changes over 12 months, including pain intensity, emotional, physical, and cognitive functioning, health-related quality of life, and telomere length; and 3) Among those initiating MM, examine which MM product characteristics (i.e., THC:CBD ratio, administration route, dose) predict more improvements in outcomes defined in Aims 1&2 or more side effects, and whether individual differences (e.g., sex, baseline pain phenotyping, expectancy) moderate the relationship. With multisource data collected in real-time and over 12 months, our results will contribute to the greatly needed scientific evidence on: 1) whether MM can reduce pain and improve physical/emotional functioning in short term among older adults; 2) whether effects of MM last for 12 months and demonstrate quality of life improvements or cognitive changes; 3) whether health benefits and consequences differ by MM product type; and 4) which subgroups of patients may benefit more from MM use.

NIH Research Projects · FY 2026 · 2022-02

People vary considerably in their response to and in the effects of exposure to chemical toxicants and biological toxins. As a result, the risk of adverse outcomes associated with exposure for different individuals and populations can be widely divergent. Gene by environment (G x E) interactions likely underlie a significant component of these risk differences. However, we remain largely ignorant of both the key genetic factors and the mechanistic association with specific toxins/toxicants. As a result, our capability to mitigate risk by the identification of susceptible individuals and populations to enable effective preventive efforts remain sorely limited. Current approaches to identify G x E interactions rely on genetic association studies which generally lack sufficient power to identify significant associations, due to the large number of genetic variants and small populations of exposed individuals. We propose, in a fundamentally different approach, to first systematically identify the common human variants which impact the functional response to a specific toxicant/toxin to delineate key candidate G X E interactions for targeted consideration in relevant individuals and populations. We will focus on functional interrogation of 1490 genes, the ToxVar set, which contain an aggregate frequency of loss of function mutations of >0.1% in all human populations assessed to date and previously identified as interacting with one or more toxicant/toxins. We contend that these commonly functionally compromised genes are most likely to impact human response to a toxin/toxicant in a significant proportion of people. We will simultaneously query the impact of functional disruption in each of these 1490 genes on the cellular response to a toxicant using coupled CRISPR screening and single cell toxicologically relevant gene expression targets (scTRGETs). We will evaluate the ToxVar-scTRGET approach to identify functionally relevant and commonly variant genes involved in cellular response to selected toxicants of high human relevance in increasingly physiologically relevant cell models.

NIH Research Projects · FY 2025 · 2022-02

PROJECT SUMMARY Dementia with Lewy body (DLB), Parkinsons Disease (PD) and Alzheimers Disease (AD) are among the most debilitating neurodegenerative disorders that afflict patients in all countries and of all nationalities. One of the Alzheimer related dementias (ADRD) national research priorities for DLB is to develop and validate imaging techniques to improve the differential diagnostic accuracy of DLB versus other diseases. Magnetic Resonance Imaging (MRI) is currently one of the most widely used diagnostic imaging techniques for detection of neuro- degenerative disorders. However, standard T1 and T2-MRI may not provide the needed sensitivity and specificity for differential diagnosis of DLB vs. AD and PD. Recently, Diffusion MRI (dMRI), specifically Diffusion Tensor Imaging (DTI), has exhibited better sensitivity to the detection of some of these disorders. However, DTI is known for its inability to cope with complex fiber geometries prevalent in the brain. This limitation can however be over- come by using sophisticated mathematical models in conjunction with high angular resolution diffusion imaging (HARDI). Our preliminary data suggests that learned micro-structural features from HARDI lead to high sensitivity and specificity in differentiating PD vs. control and others in literature have shown discrimina- tion between different stages of AD using macro-structural features derived from T1-MRI. This motivates us to combine micro- and macro-structural features via a multi-modality approach to differentiate DLB vs. PD, AD and controls. Differentiating between DLB, PD and AD is challenging because of possible overlap in clinical symptoms leading to misdiagnosis. Further, differentiating between them is of high significance since treatments including counseling for each are distinct. We propose a multi-modal approach that combines the advantages of T1- and diffusion-MRI to achieve this goal. Recently, convolutional neural nets (CNNs) have had great success in image classification tasks in computer vision and medical imaging. CNNs however can not cope with HARDI data in its native form, which are samples of functions defined on non-Euclidean (curved) domains. This motivates us to develop a novel higher order CNN that is a parameter efficient, inter- pretable geometric deep learning network possessing improved model capacity, which we call the VolterraNet. The VolterraNet will be designed for such data with the goal of facilitating the classification of DLB, PD and AD groups. Further, VolterraNet will automatically localize the regions in the brain that are significantly discriminatory of these patient groups. We will test the VolterraNet on HARDI scans acquired from a cohort of 356 Controls, 355 PD, 216 DLB and 240 AD scans obtained from a medley of data sites including the PDBP, 1Florida-ADRC and PPMI. The VolterraNet will be validated using the standard leave-k-out cross-validation method with the precision recall measure. The gold standard used will be the specialist-assigned clinical diagnosis from contributing stud- ies (e.g. consensus assignment from ADRCs). The VolterraNet will have significant benefits to the Neurology community through better detection and diagnosis of several neurodegenerative disorders.

NIH Research Projects · FY 2026 · 2022-02

Abstract There is a fundamental gap in understanding how mutations on P301 of tau cause memory impairment in fronto-temporal dementia (FTD). One pathological mechanism involves the association of aberrant tau with ribosomal complexes. However, the consequences of this interaction are unknown. The long-term goal of this work is to better understand the link between tau P301 mutations and memory impairment in FTD. The objective of this proposal is to determine the impact of mutant tau on translation. We will use human brain tissues as well as in vitro and in vivo models to study ribosomes in isolation, translation in cells, and brain pathophysiology in mice. Our preliminary results substantiate that the association between tau and ribosomal complexes impair protein synthesis. Therefore, the central hypothesis is that pathological tau inhibits translation of proteins critical for memory. The rationale for the proposed research is that understanding the tau-mediated mechanism of ribosomal dysfunction will aid in the design of therapeutic targets for FTD, which currently afflict a vast amount of individuals. Our strong preliminary data serves as support for testing the hypotheses that 1) pathological tau engages with different parts of the ribosome, 2) translational repression is present in various in vivo tau models. and 3) the ribosomes’ affinity for transcripts, capacity, and efficiency are impaired in human FTD brains. These aims have the potential of extrinsic merit to be used as screening tools for modulators of ribosomal function. Our approach is innovative because it incorporates novel assays, which offer excellent sensitivity that is not achievable by more traditional approaches. This work is significant because it departs from the status quo by testing a new mechanism in which translation dysfunction mediates tauopathic symptoms. This work is expected to advance the field by filling the gap in understanding of tau-mediated brain dysfunction. This knowledge will serve to better characterize the link between tau and memory impairment in order to develop novel therapeutic strategies.

NIH Research Projects · FY 2026 · 2022-01

ABSTRACT Opioid misuse is a major source of morbidity and mortality in the U.S. and represents a pressing public health crisis. Opioid-related overdose deaths have more than quadrupled since 2002. Oxycodone (in Percocet™ and Oxycontin™) is reliably among the medications commonly prescribed for pain, but is also widely abused and involved in overdose deaths. Despite its abuse potential, oxycodone is effective for reducing acute pain. There is an urgent need for interventions that preserve the analgesic properties of oxycodone while curtailing its abuse potential. A promising adjunctive treatment option for pain management, that could simultaneously reduce the abuse liability of opioids, is syntocinon (the intranasal formulation of the neuropeptide oxytocin). Syntocinon may reduce opioid abuse potential, and simultaneously has analgesic properties. Animal models have shown that oxytocin decreases opioid intravenous self- administration and reverses oxycodone conditioned place preference. Rat models of pain show that oxytocin enhances anti-nociception (blocking of painful stimuli), and in humans, syntocinon administration decreases pain sensitivity experimentally. Further, evidence in animals and humans support the shared brain structure and function changes associated with both addiction and chronic pain, which may be modulated by oxytocin administration. Based on the existing literature, we propose that syntocinon will significantly reduce abuse liability of opioids and reduce experimental pain via its effects on brain structure, function and biochemistry. Thirty healthy recreational opioid users will self-administer 48 IUs of intranasal syntocinon (or placebo) shortly after oral oxycodone (0, 2.5, 5.0 mg) in a double-blind, randomized, placebo-controlled, within- subjects laboratory study. Subject-rated abuse liability and cardiovascular and respiratory responses will be assessed before and repeatedly for 5 hours following drug administration. Pain and neurobiological measures will also be collected, including a standardized experimental pain battery (i.e., quantitative sensory testing) and a multi-modal neuroimaging battery (i.e., brain structure, function, and biochemistry). This study has tremendous potential for public health impact in examining intranasal oxytocin as a promising agent for reducing opioid addictive potential, while effectively reducing pain, which could substantially advance the field of pharmacotherapy and carve out a novel treatment option. This study will also advance scientific understanding of neurobiological mechanisms underlying the link between abuse potential and pain. This research will also facilitate the PI’s career goals and path to independence by developing expertise in 1) multi-modal assessments of pain; 2) neuroimaging techniques as they relate to addiction and pain; 3) deepen current expertise in addiction and human behavioral pharmacology in the context of opioid administration and translation; 4) grant and manuscript writing skills; and 5) enhance management and supervision skills. This multidisciplinary team is uniquely suited to mentor the PI in these areas and address the proposed aims.

NIH Research Projects · FY 2026 · 2021-12

Project Summary/Abstract The nematode Caenorhabditis elegans relies on small-molecule signals to control its development, metabolism, physiology, and behavior, and these signals play conserved roles in many parasitic nematode species. This MIRA application outlines our ongoing efforts to understand the structures, biosynthesis, and mechanisms of several important classes of small-molecule signals, including (1) the ascarosides – a broad family of pheromones secreted by C. elegans that the worm uses to induce the stress-resistant dauer larval stage and to coordinate various behaviors, (2) the N-acyl glutamine nacq#1 – a pheromone that males preferentially secrete to counter the effects of dauer-inducing ascarosides on hermaphrodites and promote reproductive development, and (3) the nemamides – a family of hybrid polyketide-nonribosomal peptides that serve as hormones in the worm and promote starvation survival through a poorly understood mechanism. We target the biosynthetic pathways to these signaling molecules in vivo by generating precise mutations in the worm genome using CRISPR-Cas9 and analyzing the effects of these mutations on the primary and secondary metabolome of the worm using comparative metabolomics. This approach enables us to map the biosynthetic pathways to these natural products, to identify additional signaling molecules produced by these pathways, and to determine how these pathways intersect with other metabolic pathways in the worm. We rigorously confirm the role of specific enzymes in the pathways by reconstituting the pathways using in vitro enzymatic assays, organic synthesis of biosynthetic intermediates, and structural studies. With the support of this award, we will investigate the biosynthesis and mechanism of the nemamides, as well as the biological roles of the two essential and enigmatic neurons where the nemamides are produced, the canal-associated neurons (CANs). We will use nemamide biosynthesis, which requires genes that are distributed throughout the worm genome, to understand how the biosynthesis of complex secondary metabolites is controlled in the context of an animal system. Furthermore, we will investigate how this biosynthetic pathway intersects with the biosynthetic pathways of other secondary metabolites, including the ascarosides and nacq#1. A central focus will be how the worm regulates the production and trafficking of these different small-molecule signals in response to different factors and environmental conditions in order to coordinate its development, metabolism, and physiology. This work will provide insights into how C. elegans and other nematode species use small-molecule signals to control important conserved downstream signaling pathways, such as the insulin pathway. Furthermore, given the conservation of these small-molecule signals in parasitic nematode species, this work will provide new chemical tools and strategies to interfere with the life cycles of those nematodes.