Brigham And Women'S Hospital

NIH Research Projects · FY 2025 · 2022-08

The broad objective guiding our research is to provide critical insights to clinicians and decision makers regarding the value of interventions to diagnose, prevent and reduce progression of physical frailty (PF) in people with HIV (PWH). More than a million persons in the United States live with HIV, a previously fatal infection that has become a highly treatable chronic condition with the use of antiretroviral therapy. The life expectancy of PWH now approaches that of the general population, revealing an earlier than expected and growing prevalence of PF. PF carries substantial individual and societal burden. If unmanaged, it may lead to loss of independence, recurrent falls, fractures, disability, and death. Routine screening and management of PF has not been part of the treatment guidelines, which instead focused on opportunistic infections early in the HIV epidemic, and more recently on HCV co-infection, CVD, and tobacco and other substance use disorder. The challenges in diagnosing and managing PF and its associated conditions in PWH are further exacerbated by the gap between ‘what we know’ and ‘what we do.’ Evidence indicates that pre-frailty and early stages of PF are reversible with timely diagnosis and effective interventions. However, this evidence has not been translated to routine HIV care. Regular frailty assessment is essential to prevent falls, fractures and other consequences, yet most PWH have not been assessed for PF. Evidence also suggests that multimodal interventions including cardiovascular and strength exercise in conjunction with fall prevention, treatment of osteoporosis, and careful medication de-escalation are effective in reducing musculoskeletal manifestations of PF. There are similar benefits for PWH, however this evidence has not been translated into routine HIV care. Guidance on choosing among effective interventions to maximize health benefits for PWH with constrained budgets is lacking. Knowledge of the cost-effectiveness (value) and budgetary impact of these programs would help facilitate translation of research findings into clinical management of PWH. Cost-effectiveness analysis is an important methodology that helps to inform choice among multiple efficacious programs when resources including data, time, and money are limited. We propose to develop a computer simulation model that portrays the natural history and treatment of PF in PWH to narrow the gap between evidence and practice by assessing the value of three major strategies to prevent and attenuate progression of PF in PWH: 1) timely diagnosis of PF; 2) implementation of structured strengthening and cardiovascular fitness improvement exercise programs to reduce falls and fractures and prevent PF incidence and slow its progression; and 3) use of fall prevention programs, including polypharmacy de-escalation, osteoporosis screening and diagnosis and management to reduce falls and fractures.

NIH Research Projects · FY 2025 · 2022-08

Project Summary/Abstract Mucus dysfunction plays a critical role in airway diseases like chronic bronchitis (CB) and chronic obstructive pulmonary disease (COPD). COPD affects approximately 29 million people in the US and is the third leading cause worldwide. The public health and clinical relevance of “mucus dysfunction” are better understood when one focuses on the clinical manifestations of this process —chronic cough and phlegm and chronic mucus hypersecretion/CB. Up to 32% of community-living individuals report chronic respiratory symptoms and present with normal lung function. The presence of chronic symptoms in these individuals is associated with a substantially increased risk of future hospitalization and mortality. In this proposal, we will use an objective, reproducible assessment of mucus dysfunction. We will identify and score mucus plugging on chest computed tomography (CT) scans from community-living individuals participating in two population-based studies, the Framingham Heart Study (FHS) and Coronary Artery Risk Development in Young Adults (CARDIA). In Aim 1, we will determine the clinical relevance of CT-based mucus plugging. We will evaluate the associations of mucus plugging with lung function, respiratory symptoms, and chronic bronchitis (Aim 1a); and examine whether 5-yr. Persistent CT-based mucus plugging is associated with the decline in FEV1 and future COPD (Aim 1b). In Aim 2, we will examine whether modifiable factors affect CT- based mucus plugging. We will determine whether air pollution and marijuana smoking are associated with increased odds of CT-based mucus plugging and define whether cardiorespiratory fitness is related to decrease mucus plugging. Finally, in Aim 3, we will determine genetic resilience/susceptibility to mucus dysfunction. We will use CT data from the FHS and CARDIA cohorts and genome-wide sequencing data from the TOPMed initiative to identify common and rare variants associated with CT-based mucus plugging. This study will increase our understanding of the clinical implications of an imaging-based mucus dysfunction phenotype at the population level, providing a tangible target for the interception and prevention of chronic airway disease while identifying susceptibility, risk, and protective factors for this process.

NIH Research Projects · FY 2025 · 2022-08

Project Abstract: Alzheimer’s disease (AD) and related dementias (ADRD) represent an enormous burden for patients, families, and health care systems, underscoring the urgent need for efficacious, widely-accessible, and cost- effective disease-modifying therapies. The over-production of longer, aggregation-prone Ab fragments (esp. Ab42 and 43) relative to shorter, non-aggregating fragments (esp. Ab37 and 38) appears to be a critical initiating pathological event in both late-onset, sporadic AD (LOAD) and Autosomal Dominant AD (ADAD). The balance between production of aggregating and non-aggregating forms of Ab is a direct result of the efficiency and kinetics with which the γ-secretase complex sequentially cleaves b-amyloid precursor protein (APP). Subtle alterations in γ-secretase function can have profound neurodegenerative and cognitive consequences, while modulation of γ-secretase has therapeutic potential in both LOAD and ADAD. Over 200 pathogenic variants in Presenilin-1 (PS1), the key catalytic subunit in the γ-secretase complex, have been identified and are the most common cause of ADAD. Despite near complete penetrance, there is substantial heterogeneity in age of symptom onset (a range of >30 years) and rates of cognitive and biomarker change between PS1 variants. In this proposal, we hypothesize that differences in γ-secretase function between ADAD-causing PS1 mutations measured in cell-based, biochemical, and primary neuronal model systems will help explain heterogeneity in age of symptom onset, cognitive, and biomarker changes seen in PS1 pathogenic variant carriers in vivo. We test this hypothesis through systematic characterization of γ-secretase function across PS1 pathogenic variants and comparing the resulting immunoassay and mass spectroscopy measures of g-secretase function to cognitive and biomarker data from carriers of corresponding PS1 variants participating in the Dominantly Inherited Alzheimer’s Network Observational Study (DIAN-Obs), a large international study in which over 80 unique PS1 pathogenic variants are represented. Determining which variant-specific differences in γ-secretase function translate into differences in age of symptom onset and cognitive and biomarker trajectories in PS1 carriers represents a unique opportunity to elucidate AD pathobiology, inform therapeutic and biomarker development, and impact ADAD clinical trials.

NIH Research Projects · FY 2026 · 2022-08

Abstract We propose to investigate and validate novel MRI pulse sequences and quantitative measures for mapping primary brain tumor margins and infiltration. We will focus on glioblastomas (W.H.O. grade IV gliomas (GBM)), the most prevalent and deadly primary brain tumor in adults. These progressive brain tumors infiltrate into the brain parenchyma and grow with diffuse margins. However, current clinical imaging modalities fail to reliably define the extent of glioma infiltration, negatively impacting patient care. Neurosurgeons are faced with uncer- tainty about what tissue should be removed when planning an optimal resection, and radiation oncologists must design radiation fields based on an incomplete understanding of the tumor's extent. Therefore, there is an unmet need for patient-specific, personalized mapping of tumor margins (including what is within the radiologi- cally defined margin using current state-of-the-art imaging and what is beyond it) in order to improve clinical treatment of gliomas via methods such as surgery, radiation therapy, or drug delivery. Meeting this unmet need requires improved imaging of brain and tumor tissue microstructure. We recently proposed q-space trajectory imaging (QTI), which goes beyond conventional diffusion MRI to measure the correlation of water molecule motion between different directions, improving mapping of tissue and tumor microstructure. Recent work has also demonstrated the potential of quantitative MRI (T2-relaxome- try) for detecting infiltrative tumor growth in the peritumoral area of gliomas. In fact, the joint distribution of dif- fusion-relaxation measures can provide important information that is missing in independently acquired T2-re- laxometry or QTI data alone. In this project, we plan to develop, investigate, and validate rQTI (a novel combi- nation of T2-relaxometry and QTI) for the critical clinical application of glioma margin and infiltration mapping. To reach this goal, first we will create a comprehensive and unique diffusion-relaxation (rQTI) and histology dataset for the study of glioma infiltration and margins. This work will leverage a mouse model in which we will implant patient-derived xenografts obtained from human GBMs to closely recapitulate key features of human brain tumors such as microstructure and infiltration. Second, we will develop an optimized clinical acquisition for computing rQTI-based microstructure measures that are predictive of histology, in under 10 minutes of ac- quisition time. Third, we will validate rQTI-based microstructure measures against histopathology in 30 patients with GBM. Patients will be scanned with the optimized rQTI sequence and tissue samples will be obtained us- ing clinically indicated stereotactic sampling of tissue and/or stereotactic biopsy. Overall, the successful outcome of this study has the potential to improve non-invasive mapping of GBM margins and to reveal infiltration that was previously invisible on imaging. This is expected to provide important information for GBM treatment planning, with the potential of improving patient survival and quality of life.

NIH Research Projects · FY 2025 · 2022-08

Project Summary Optimizing blood cell support for specific patient groups and clinical settings is an emerging priority in transfusion medicine. Patients undergoing hematopoietic cell transplantation (HCT) require significant transfusion support (including red blood cells, platelets, and granulocytes) because of the transplant-related bone marrow (BM) dysfunction state. However, challenges and shortcomings still exist for modern transfusion practices in the peri-transplant setting, limiting their clinical efficacy and cost effectiveness. Mechanisms underlying the effect and effectiveness of blood transfusion in the peri-transplant setting are important, understudied, and poorly understood, representing a critical gap in our biomedical knowledge. A coordinated, multi-disciplinary P01 program project on such mechanisms is warranted, considering the medical and public health significance of blood transfusion and cellular therapies, and will be innovative, constituting a distinct area of investigation in the current NIH portfolio. The long-term thematic objective of this research program is to provide more effective transfusion support for HCT recipients by better understanding the molecular and cellular mechanisms underlying the effect and effectiveness of blood transfusion in the peri-transplant setting. Drs. John Manis, Leslie Silberstein, and Shin-Young Park (Project 1) will elucidate the dynamic relationship between BM niche and HSPC in sickle cell disease (SCD) patients, specifically hypothesizing that insight into how BM vascular and perivascular niches are distorted in SCD and restored by RBC transfusion shall lead to opportunities for targeted intervention in HSC transplantation in SCD patients. Drs. Hongbo Luo and Li Chai (Project 2) will study cell death signaling in granulocyte transfusion (GTX), specifically hypothesizing that GTX can be improved by simultaneously targeting multiple death pathways. This study will assist us to design novel therapeutic strategies for improving the efficacy of GTX and combating neutropenia-related infections in the peri-transplant period. Drs Jose Cancelas and Yi Zheng (Project 3) will focus on platelet transfusion which is commonly used to prevent or treat bleeding in thrombocytopenic patients, including HCT recipients. The goal is to elucidate the role of RHOA/RAC1 signaling in cold storage-induced clearance of platelets and to design novel clinical procedures (e.g. pharmacological inhibition of RHOA) for the long-term storage and application of platelets in transfusion medicine. The 3 research projects will be bolstered by a unique Cytometry and Imaging Core, led by Dr. Shin-Young Park, to maximize efficiency, economy, and productivity. An Administrative Core will coordinate the activities of these projects and cores to form a cohesive whole. The overall scientific synergy of ideas, reagents and expertise afforded by the multiple collaborations shall enable this Program Project to advance our understanding of the biology of blood transfusion, and to apply findings made toward enhancing the effectiveness of modern-day blood transfusion therapy for specific patient groups in the peri-transplant setting.

NIH Research Projects · FY 2025 · 2022-08

The goal of this clinical informatics project is to develop computational techniques to model and analyze brain blood vessels for detecting morphometric abnormalities that are hallmarks of cerebrovascular diseases (CVDs). The project addresses an important challenge in neuroradiology and neurosurgery: how to accurately diagnose CVDs on computed tomography angiography (CTA). CVDs include intracranial aneurysms, stroke, intracranial vascular stenosis, dural fistula, and other disorders of the brain vasculature, and these diseases have severe outcomes as they cause hemorrhage, stroke, neurological damage, and death. In fact, each year, CVDs cause more than 100,000 deaths in the US, and an even larger population suffers permanent damage, including stroke, paralysis, and loss of speech. If we can diagnose CVDs more accurately and promptly, mortality and morbidity can be significantly reduced. Brain imaging is a first line diagnostic for CVDs with the image hallmarks being brain blood vessel abnormalities. Yet diagnosis is very challenging because a clinician needs to sift through and zoom in and out of and rotate a large number of images to examine each blood vessel for malformation, whether it is a narrowing or the formation of intracranial aneurysms on blood vessel walls. Similarly, a neurosurgeon needs to read brain scans right before an operation to locate the positions of abnormalities. Our specific aims of this project are to develop novel computational techniques including deep learning to model and analyze blood vessels to detect abnormalities and highlight their locations for clinicians to examine further. While computers are not yet sophisticated enough to make diagnoses like a trained clinician, computers can perform more objectively and quickly, compared to human experts, the necessary complex shape analysis and quantification, such as identifying abnormal widening or narrowing of blood vessels and detecting protrusions on blood vessel walls. To address the request from clinicians that they would benefit significantly from computer-aided detection of abnormalities and, once abnormalities are marked, they can make highly accurate diagnosis and classification of the underlying CVDs, we designed an informatics approach as a computer-aided tool to analyze CTA images. We will model both individual blood vessels and the whole vasculature in the 3D space. Then, from the vasculature, we will develop and implement a multi- channel deep learning model focused on shape analysis to detect blood vessel abnormalities. Finally, abnormalities will be marked in colors in 3D to allow clinicians to make more accurate diagnoses, plan preventative treatments, and perform precise surgeries to benefit patient health.

NIH Research Projects · FY 2025 · 2022-08

ABSTRACT Reproduction and metabolism are closely regulated to ensure the survival of the organism and the species. The central control of energy balance depends on the intricate interaction of central and peripheral signals that ultimately regulate food intake and energy expenditure (EE). Among the central signals involved in the control of energy balance, melanocortins (a-MSH) produced by proopiomelanocortin (POMC) neurons play a critical role inducing satiety and increasing EE. a-MSH binds the melanocortin receptor 4 (MC4R) at the level of the paraventricular nucleus to induce satiety, however, the site of action of melanocortins to regulate EE remains under-characterized. Recently, the reproductive neuropeptide kisspeptin, encoded by Kiss1, has been identified as a metabolic factor in several animal models, for example, kisspeptin signaling deficient mice develop obesity. Kisspeptin has been demonstrated to be essential for the activation of the reproductive axis, however, its role in metabolism requires further investigation. Our preliminary data expands on these findings and suggest that melanocortin signaling to Kiss1 neurons is involved in the control of EE. We have showed that Kiss1 neurons a) express MC4R, b) respond directly to the stimulation by a-MSH, c) are direct targets of POMC neurons, which post-synaptically regulate Kiss1 neurons, and d) innervate and activate Lepr neurons in the dorsomedial hypothalamus (DMH) through glutamate release. In addition, we have demonstrated that the specific removal of MC4R from Kiss1 neurons induces an increase in body weight (BW) due to a decrease in EE without changes in overall food intake or activity and without causing hypogonadism. Therefore, we hypothesize that Kiss1 neurons serve as mediators of the melanocortin action to regulate EE through the control of LeprDMH neurons, thus uncovering a novel pathway of action for melanocortins in the control of energy balance that links reproduction and metabolism. We propose to 1) evaluate the changes in EE after ablation or chronic activation of Kiss1 neurons; 2) assess the overall contribution of Kiss1 neurons to the melanocortin regulation of EE through the re-insertion of MC4R in Kiss1 neurons of MC4RKO mice; 3) map the neurocircuitry underlying this role through the identification of neuronal projections and optogenetic activation of Kiss1 neuron terminals; 3) assess the contribution of kisspeptin co-transmitters in the control of EE. Kiss1 neurons are the nodal regulatory center of reproductive function and are, therefore, sensitive to changes in the circulating levels of sex steroids. Thus, the successful completion of this proposal may offer the first approach to a comprehensive pathway linking reproductive status and the regulation of energy expenditure that could explain the frequently observed increase in BW after menopause in women or men with low testosterone. Moreover, the characterization of Kiss1 neurons as an active player in the control of energy balance will inform the development of new strategies to improve the treatment of metabolic disorders.

NIH Research Projects · FY 2026 · 2022-08

Project Summary Aging has a complex underlying biology characterized by a progressive loss of cellular and physiological function and this deterioration is strongly correlated with degenerative disease. In the bone marrow, aging markedly reduces the capacity of hematopoietic stem cells (HSCs) to self-renew and differentiate into lymphoid lineages, resulting in hindered immune function and systemic effects on multiple tissues, such as muscle repair after injury. Bone marrow from young recipients has been shown to rejuvenate aged bone marrow as well as systemically in other tissues. However, the exact HSC and progenitor cell states as well as other factors that drive the rejuvenating effects are not well understood. Profiling of HSCs and other bone marrow cell types during aging and an understanding of the transcription factors (TFs)-that control HSC self-renewal and their changes in activity during aging could provide new therapeutic approaches with the potential to reverse both blood-specific and whole-animal effects of aging. TF-based interventions, such as partial reprogramming, have shown promise to promote stem-cell cycling and regeneration. However, current approaches are limited to a small set of predetermined TFs, commonly the Yamanaka factors Oct3/4, Sox2, Klf4 and c-Myc, and have only been demonstrated in a select set of tissues. Furthermore, the diversity of the HSC population, containing both senescent cells and long-term renewing state (LT-HSC) among other subtypes, makes discovery of master regulators challenging, and existing approaches do not address this heterogeneity. We hypothesize that high- resolution single cell RNA sequencing (scRNA-seq) of HSCs from mice of different ages will reveal putative TF regulators of the aging process, and that these candidates can reprogram aged HSCs towards LT-HSC and quiescent states capable of niche restoration to reverse age-associated phenotypes. We will profile molecular signatures of aging in HSCs at single cell resolution and use these data to both develop metrics for aging and nominate TFs to promote LT-HSC restoration and rejuvenation. We will synthesize selected TFs for pooled screening allowing for rapid evaluation of their reprogramming effects in vitro and in vivo. Coupling these pooled perturbations in vivo with scRNA-seq readouts will allow for evaluation of HSC rejuvenation via our aging signatures and measurement of lymphoid/myeloid skew. Candidate TFs that demonstrate the strongest potential for rejuvenation of LT-HSCs will be tested individually and in combination for modification of whole-organism phenotypes, including increased repopulation potential, reduction of inflammatory factors, and improvement of muscle repair in response to injury. The repurposing of novel TFs regulating HSC rejuvenation as new therapeutics for aging-associated disease provides a new framework for cellular engineering. This proposal, coupling transcriptomic readouts and screening for discovery of new regulators of cell states, serves as the foundation for TF-based interventions for disease, both in aging and in broader human health.

NIH Research Projects · FY 2025 · 2022-08

Nearly 1 in 2 US adults has hypertension, and it is a leading cause of myocardial infarction, stroke, and death. Despite the importance of hypertension and the widespread availability of medication treatment, only 44% of patients had controlled blood pressures in 2018. This is in part due to the way in which we deliver care, and new strategies are needed to achieve better blood pressure control. Team-based care with medication titration by a non-physician is a promising approach, but the cost and infrastructure required make this option less feasible. An alternative strategy is to have patients self-manage their own hypertension by checking blood pressures and following an algorithm, pre-planned between the patient and primary care doctor, to intensify their medications at home. Despite evidence for the effectiveness and cost- effectiveness of this approach, it has not yet been incorporated into routine care. In this project, we propose to develop an implementation-ready antihypertensive self-titration intervention informed by qualitative interviews and real-world assessments of antihypertensive adherence. The proposed aims are to: (1) explore barriers and facilitators to the implementation of antihypertensive self-titration in routine US primary care; (2) assess adherence to antihypertensive treatments; and (3) develop an implementation-ready antihypertensive self- titration protocol, perform usability testing, and prepare a proposal for a pragmatic, randomized trial to test the intervention’s effectiveness. The overarching goal of the project is to develop an innovative alternative model of hypertension care that has the potential to improve blood pressure control, patient self-efficacy, and disease understanding Dr. Haff is a practicing primary care physician committed to a career in research to improve the prevention and treatment of cardiometabolic disease, and this proposal includes a training plan that will accelerate her career development in the areas of implementation science, qualitative methods, health services research methods, and scientific writing. The mentorship team, led by Niteesh Choudhry, an expert in health services research and implementation science related to cardiometabolic disease, includes well-known experts in preventive cardiology (Paul Ridker, co- mentor), biostatistics (Robert Glynn, co-mentor), and implementation science and qualitative methods (Karen Emmons, co-mentor), and will ensure successful completion of the proposed project and training. By the conclusion of this program, Dr. Haff will be able to independently design, target, and evaluate interventions for cardiometabolic disease. The results of the proposed K23 will be invaluable pilot work for a planned R01-level application.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY Background: Disclosure of HIV is a key step in prevention, however, few evidence-based resources exist to support HIV disclosure among men with HIV. Candidate: My long-term goal is to become an independent, NIH-funded clinical researcher dedicated to interventions to support HIV and sexually transmitted infection prevention and treatment in resource limited settings. Research: The goal of this proposal is to develop and test an HIV disclosure intervention focused on men with HIV meeting the following eligibility criteria: with sexually transmitted infection symptoms who are either not accessing antiretroviral therapy or are accessing antiretroviral therapy but without viral suppression. In Aim 1, I will identify the unique HIV disclosure needs and preferences to support HIV disclosure through in-depth qualitative interviews with up to 30 men with HIV meeting eligibility criteria. In Aim 2, I will utilize the findings from Aim 1 to adapt interventions with HIV disclosure components in order to develop a novel HIV disclosure intervention focused on men with HIV. The intervention will be iteratively refined through focus group discussions with up to 20 participants, their sexual partners, and a community advisory board. In Aim 3, I will recruit 70 men with HIV meeting eligibility criteria for participation in a randomized controlled trial to pilot test the intervention against an attention-matched control group. Participants will be encouraged to bring their sexual partners for study enrollment and HIV testing and counseling. Up to 15 men with HIV and their sexual partners will be invited for qualitative interviews. I will measure the primary outcomes of acceptability and feasibility by mixed methods. Training: To achieve my aims and gain research independence, I require additional training in: 1) behavioral science theory for behavioral intervention development and assessment 2) methods for behavioral intervention development, and 3) advanced behavioral clinical trial analysis. Based on my previous research experience and success, support from an exceptional mentoring team, strong institutional commitment, and an innovative research plan, I am well-positioned to become an independent clinical investigator focused on HIV and sexually transmitted infection prevention and treatment in resource limited settings.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY Mice, monkeys, and humans can regenerate their digit tips following amputation. This innate form of composite tissue regeneration is a highly coordinated process involving multiple tissue types interacting to form a replacement digit tip with the proper composition and pattern. Defining what is unique to the digit tip in terms of molecular signals or cell types, and how it relates to regeneration, can inform broader regeneration efforts of non-regenerative tissues. One foothold into this process is the recent cellular characterization of the mouse digit tip blastema, the collection of progenitor cells that forms following amputation that is necessary to give rise to the regenerating tissue. Our single cell RNA sequencing-based analysis of the blastema identified 13 molecularly distinct fibroblast populations. With this, we now have specific cellular populations to individually assess for their function(s) in digit tip regeneration. We propose that the subpopulations of fibroblasts in the regenerating mouse digit tip encompass separable roles including progenitors, structural, and niche-factor- producing cells, of which a subset may promote composite tissue regeneration. In this proposal, we focus on digit tip fibroblast heterogeneity and aim to determine the origin, function, and regenerative potential of each of these populations. We will analyze the spatial organization of the fibroblast subpopulations in mouse and human digit tips and determine those comprised of progenitor cells. Using single cell RNA sequencing with lineage tracing, we will determine when the digit tip heterogeneity of the adult digit is established, and define the cellular plasticity and regenerative contribution of the fibroblast populations to the regenerated tissue. Finally, we will investigate how the digit tip fibroblast subpopulations relate in identity and function to fibroblasts from non-regenerative proximal amputations. Collectively, the data generated in this project will provide a comprehensive understanding of the heterogeneous population of digit tip fibroblasts in the context of regeneration, which will lay the foundation for composite tissue regeneration on a broader scale.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY/ABSTRACT Remodeling of the extracellular matrix (ECM) is a central mechanism by which central nervous system (CNS) reward substrates, such as the nucleus accumbens (NAc), adapt to unpredictable stressors in the environment. The ECM is a spatially, molecularly, and cellularly heterogeneous structure that impacts neural activity, cell-cell interactions, and blood-brain barrier integrity. However, exposure to repeated unpredictable stress leads to molecular and cellular reorganization of the ECM, which influences circuit-level adaptations to stress guiding neural activity and behavior. ECM remodeling is partially controlled by integrins: transmembrane receptors that regulate the ECM by anchoring ECM-associated peptides to multiple cell types. Cellularly, the ECM consists of neuronal processes and also the endfeet of astrocytes, which are CNS-resident glial cells. Astrocytes make contacts throughout the ECM by expressing multiple integrins that actively participate in ECM remodeling. Through these intimate interactions within the ECM, astrocytes are poised to control neural activity and behavior. However, the mechanisms and cell-cell interactions by which astrocytes shape the NAc ECM in response to unpredictable stress are largely unknown. In PREVIOUS RESEARCH EFFORTS I focused on characterizing the responses of astrocyte subsets in the CNS in response to inflammation. I identified the b1 integrin CD29 as a top marker expressed by astrocytes throughout the CNS. CD29 participates in multiple complexes with other integrins that affect ECM organization. My previous data suggest that CD29+ astrocytes might be composed of heterogeneous subsets that play complementary roles in remodeling the ECM by interacting with distinct cell types. However, it has been historically challenging to rapidly study the interactions of astrocyte subsets in vivo. To this end, I recently developed a new technique called RABID-seq that profiles astrocyte interactions with other cells at high throughput, on the genome-wide scale, and with single-cell transcriptomic precision. Thus, RABID- seq is a candidate tool to define the interactions of CD29+ astrocyte subsets in the ECM in response to unpredictable stress. In this proposal, I AM PURSUING A NEW RESEARCH DIRECTION to identify how exposure to unpredictable stress shapes CD29+ astrocyte interactions, localization, and function. I hypothesize that defined subsets of CD29+ astrocytes regulate distinct ECM domains that influence behavioral responses to unpredictable stress. I propose to test this hypothesis in the following Specific Aims. In Aim 1, I will define the interactions of integrin-expressing CD29+ astrocyte subsets within the NAc in response to acute and chronic unpredictable stress using RABID-seq and CITE-seq. In Aim 2, I will spatially map the ECM domains occupied by each subset of CD29+ NAc astrocytes via spatial transcriptomics and CD29 cKO mice to uncover how CD29+ astrocytes remodel the ECM in response to stress. In Aim 3, I will define how CD29+ NAc astrocytes regulate the activity of parvalbumin+ interneurons in a reward-seeking paradigm after exposure to unpredictable stress. IN SUMMARY, I will study how stress affects the interactions, location, and function of NAc CD29+ astrocytes.

NIH Research Projects · FY 2026 · 2022-08

Anxiety disorders comprise a spectrum of conditions, including panic disorder, generalized anxiety disorder, obsessive-compulsive disorder, posttraumatic stress disorder, social anxiety disorder, and phobias. Their lifetime prevalence among women has been reported to be as high as 30%, so these disorders frequently complicate pregnancy. Insomnia is also very common during pregnancy, with a prevalence of nearly 40%. Pharmacological treatment with benzodiazepines or non-benzodiazepine sedative hypnotics is frequently indicated for severe anxiety and insomnia; approximately 4% of pregnant women uses one of these classes of medication during their pregnancy. Polytherapy among women using these medications is common, with 30- 40% being co-prescribed at least two additional psychotropic medications. Benzodiazepines and non- benzodiazepine sedative hypnotics cross the human placenta and may therefore have the potential to alter normal intrauterine development of fetal growth, anatomic structures, physical functioning, and postnatal development. The American College of Obstetricians and Gynecologists recommends that decisions regarding mental health treatment during pregnancy be made jointly between a woman and her mental and obstetrical health providers prior to pregnancy. Unfortunately, rigorous and comprehensive safety data to inform the risk-benefit trade-off are sparse, evidence is conflicting, and numerous safety concerns have been raised. The objective of the proposed studies is to address this critical information gap by generating high-quality evidence on the safety of benzodiazepines and non-benzodiazepine sedative hypnotics during pregnancy considering a broad range of clinically relevant adverse pregnancy outcomes, including major congenital malformations, spontaneous abortion, preterm birth, low birth weight, small for gestational age, hypoglycemia, respiratory problems, NICU admission, and neurodevelopmental disorders. The use of large, population-based cohorts of publicly and privately insured pregnant women (N ≈ 4.5 million) will enable quantification of effects with great precision, as well as exploration of the effects for specific drugs, doses, gestational timing of exposure, and polytherapy. As is the case for all studies evaluating drug safety in pregnancy given that they are observational in nature by necessity, the most important challenges relate to the potential for confounding, as well as misclassification of exposures and outcomes as documented in existing healthcare data. The project will benefit from the multidisciplinary team’s deep experience and established track record overcoming these challenges in perinatal psychiatry research using highly innovative design and advanced computational approaches. The findings will have a direct and large public health impact by enabling treatment to be tailored for the large number of women that struggle with perinatal anxiety and sleep disorders.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY: Toward Connectomic Deep Brain Stimulation in Obsessive Compulsive Disorder Obsessive-Compulsive-Disorder is a leading cause of disability worldwide with about 10% of patients that are refractory to conventional treatment while suffering from substantial burden of disease. Deep Brain Stimulation (DBS) is a treatment option for these patients, but while some respond excellently to this invasive procedure, not all patients do. One reason could be that we conceptualize DBS to modulate a brain region, rather than a brain network. The goal of this project is to causally link symptom specific improvements in OCD to the stimulation of specific brain networks. By doing so, we will be able to derive symptom-specific network targets for treatment in DBS. In our preliminary research, we identified a specific network target that was associated with optimal response following DBS to four different surgical targets applied world-wide. Our findings were based on the largest multi-center OCD cohort with DBS studied to date (N = 50) and have been confirmed by four additional centers since they were published. While results are promising, three gaps remain before moving toward prospective clinical trials. The aim of this R01 will be to close these gaps. First, we have defined optimal networks by means of structural and functional connectivity but, so far, it remains unclear which of these two modalities (or a combination of both) is best suited to guide DBS. Second, while modulating the network leads to optimal response on a group level, OCD is a heterogeneous disease and symptoms in each patient are different. We will determine which specific symptoms (obsessions, compulsions, depression and anxiety) map to which specific components of the network. This will pave the way to personalize DBS and to define symptom-specific targets tailored to individual patients. Third, while most of our preliminary research is based on normative connectome atlases of the human brain, connectomes of patients with OCD present with individual differences. We will test how much additional variance in clinical outcomes can be explained when using patient-specific instead of normative connectomes. Completion of these aims will validate and refine our OCD response network. If successful, this study will facilitate future trials directly targeting our brain circuit with DBS for OCD.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY/ABSTRACT This proposal describes an innovative surgical and bioengineering solution to the challenge of locoregional recurrence for sarcomas. Locoregional recurrence (LRR) is the most common pattern of failure for retroperitoneal, abdominal, and pelvic sarcomas. Despite a macroscopically complete resection, surgical margins are frequently positive on final pathology due to large tumor size and anatomic complexity, resulting in LRR rates of up to 40% even in leading referral centers with expertise in sarcoma. High mortality is commonly due to locoregional disease rather than distant failure, and therefore strategies to improve survival must address LRR. Trials evaluating perioperative and/or intraoperative external beam radiotherapy, single-dose hyperthermic intraperitoneal chemotherapy, and systemic chemotherapy have all failed to demonstrate benefit. Our solution is a surgically implantable buttress to locally deliver high concentrations of a chemotherapeutic drug to the resection bed. Specifically, we describe the first example of an implantable, high-dose chemotherapeutic buttress for biphasic extended paclitaxel (PTX) delivery post-resection. The buttress consists of a compliant poly(caprolactone) (PCL) and poly(1,2-glycerol carbonate) (PGC) polymer blend on a mesh, where PTX is both physically entrapped within and site-specifically conjugated to PGC enabling concentrations as high as 3.3 mg/cm2 (supraPTX-buttress). The proposed experiments will test the hypothesis that the dual release profile combination of fast, but not burst, release of physically entrapped PTX followed by extended release of covalently-bound PTX will: 1) reduce LRR rates and extend survival in patient-derived xenograft (PDX) surgical models; and 2) be safe and feasible for locoregional drug delivery, achieving high local tissue drug levels with minimal systemic delivery when implanted in a large animal along tissue planes and vital structures commonly exposed during clinical cytoreductive sarcoma surgery. Importantly, substantial preliminary data support the proposed studies, well-characterized materials and rigorous experimental designs are established, and essential cross-disciplinary collaborations and expertise are in place to address the hypotheses. supraPTX-buttresses provide an unprecedented opportunity to treat sarcomas with a first-of-its-kind therapy. The specific aims of this five-year proposal are the following. Aim 1 characterizes the PTX release kinetics as well as cytotoxicity and mechanism of action of supraPTX-buttresses against resected patient-derived sarcomas in vitro. Aim 2 evaluates the efficacy of supraPTX-buttresses to prevent sarcoma recurrence following resection in multiple PDX murine models with assessment of safety, local tissue healing, and drug pharmacokinetics/biodistribution after film implantation. Aim 3 assesses the safety, feasibility, perioperative morbidity, and systemic toxicity of supraPTX-buttress implantation in a pre-clinical large animal model of retroperitoneal sarcoma surgery.

NIH Research Projects · FY 2025 · 2022-08

Project Summary Non-valvular atrial fibrillation (AF) is highly prevalent in older adults and associated with a 5-fold increased risk of cardioembolic stroke. Oral anticoagulants (OACs) can reduce this risk by ~70%, but nearly 50% of such older patients are not anticoagulated, with Alzheimer’s disease and related dementias (ADRD) being among the leading cited reasons, attributed to a higher risk of falls, medication errors, and poor adherence. Since the vast majority of thrombus formation in AF occurs in the left atrial appendage, transcatheter left atrial appendage occlusion (LAAO) has been approved in the US since 2015 as a one-time procedural alternative treatment for stroke prevention in AF patients with high risks of complications from OACs. The uptake of transcatheter LAAO has been growing at a rate of 2 to 3-fold yearly, and it is clearly changing the prescribing pattern of OACs in AF patients. However, our pilot data showed persons living with dementia (PLWDs) are significantly less likely to receive transcatheter LAAO when it is indicated. One likely barrier is that PLWDs and frail older adults were much under-represented in the randomized controlled trials (RCTs) which led to transcatheter LAAO approval. Also, several high-risk characteristics prevalent in PLWDs, including frailty, dementia severity, fall risks, and advanced kidney disease, are risk factors for both the transcatheter LAAO procedure-related complications and bleeding risks from OACs, complicating the prescribing decisions. Thus, there is an urgent need to investigate the net clinical benefit, weighing the benefits of stroke prevention against the major bleeding and procedure complications, comparing transcatheter LAAO with specific OACs in PLWDs. Our objective is to establish a prospective monitoring program in 3 large national healthcare utilization databases (Medicare, IBM Marketscan, and Optum claims data, covering ~15 million lives) from 2015-2025, linked to electronic health records (EHR). We will evaluate treatment outcomes of transcatheter LAAO vs. specific OACs in PLWDs with AF with detailed treatment effect heterogeneity evaluation by frailty, dementia severity, fall risks, advanced kidney disease, and patient-reported and family factors. We will also determine the utilization trends, predictors, and barriers of transcatheter LAAO and OACs in PLWDs, using a novel signal detection tool, TreeScan, developed by the applicant team and adopted by the US Food and Drug Administration for prospective drug safety monitoring. Our central hypothesis is that transcatheter LAAO has a favorable long-term net clinical benefit compared with OACs in PLWDs and the relative benefits vary by specific identifiable clinical factors. This proposal will yield: 1) direct benefit-to-risk data to inform the use of transcatheter LAAO and specific OACs for stroke prevention in PLWDs with AF; 2) a novel and generalizable prospective monitoring program that compares effectiveness and safety of newly marketed medical devices vs. pharmacotherapies in PLWDs with detailed treatment effect heterogeneity evaluation.

NIH Research Projects · FY 2026 · 2022-08

Summary The primary aim of this study is to determine whether NAD augmentation by administration of nicotinamide mononucleotide (NMN) improves urinary albumin to creatinine ratio, a robust biomarker of diabetes kidney disease, and other biomarkers of kidney injury in adults with diabetes kidney disease. The trial is highly significant because it offers a novel mechanism-based therapeutic strategy to treat and prevent diabetes kidney disease, a major source of morbidity and mortality in people with diabetes. This is also the first randomized efficacy trial of NAD augmentation in diabetic kidney disease, directly advancing the FOA's priority for innovative therapies targeting aging-related diseases. This phase 2, randomized, placebo-controlled, double-blind, parallel group trial enrolled adults, 30 years or older, with type 2 diabetes mellitus, UACR > 100 mg/ g creatinine, and estimated glomerular filtration rate (eGFR) >30 mL/min/ /1.73m2. Participants were randomly assigned to receive either 1.0 g NMN or placebo twice daily for 6 months with stratification by sex and age (60-75, >75 years). The aims of the project have not changed. The trial has achieved full enrollment despite major unforeseen challenges, including the rapid rise in GLP-1 and SGLT2 inhibitor use, which reduced screening yields; the addition of a third clinical site; and a DSMB- approved increase in sample size from 140 to 156 participants. These adjustments were necessary to preserve the scientific integrity of the study and successfully reach the enrollment target. However, additional participants remain under active follow-up and must be monitored through study completion to ensure safety and trial's close-out. This request for study close-out funds was necessitated by an unanticipated funding shortfall arising from major unforeseen challenges encountered during this trial, which has now successfully completed enrollment despite these obstacles. The shortfall was driven primarily by three factors: first, the rapid and unanticipated growth in the use of GLP-1 agonists and SGLT-2 inhibitors substantially reduced recruitment yields, requiring significantly greater screening and recruitment efforts, and thereby increasing associated costs, to meet enrollment goals; second, because of lower-than-expected recruitment early in the study, and with DSMB approval, we added a third site at the Lundquist Institute at Harbor–UCLA Medical Center in Torrance, CA, which meaningfully improved enrollment but also added substantial operational costs; and third, the DSMB- approved increase in sample size from 140 to 156 further increased the overall trial budget. The additional resources requested are essential to address this unanticipated shortfall and to ensure safe, rigorous close- out, including the continued monitoring of participants who remain in the study through completion.

NIH Research Projects · FY 2025 · 2022-08

Postpartum hemorrhage, defined as estimated blood loss of at least 1000 mL within 24 hours of delivery, is the leading cause of severe maternal morbidity and mortality. Annually, postpartum hemorrhage complicates 2-3% of all pregnancies and accounts for 140,000 maternal deaths globally. While clinical postpartum hemorrhage risk prediction tools have been developed, they fail to identify up to 40% of cases; as a result, no evidence-based prediction tool is currently widely adopted in clinical practice. Thus, an efficient, precise, and personalized postpartum hemorrhage risk prediction tool is urgently needed. Recently, machine learning approaches have been increasingly used to develop accurate predictive models with superior performance compared to traditional statistical approaches and to discover new predictors, with little prior pre-specification. Moreover, the explainable machine learning methods allow for transparent decision-making and ensure model generalizability. In this way, machine learning models may lead to more accurate postpartum hemorrhage prediction than currently existing tools. In addition, since up to 18% of postpartum hemorrhage risk is familial and many of the clinical risk factors associated with postpartum hemorrhage have a well-established polygenic architecture, using polygenic risk tools may further enhance postpartum hemorrhage risk prediction. In line with the NIH IMPROVE initiative goals to improve maternal safety and outcomes, we propose here to develop a high-fidelity algorithm, combining both clinical and genetic factors, to more accurately predict the risk of postpartum hemorrhage in pregnant women. We will leverage our rich patient database and state-of-the-art computational tools to: (1) develop an improved algorithm to stratify patient postpartum hemorrhage risk with a focus on transparency and high performance, and (2) delineate the contribution of genetics to postpartum hemorrhage risk. Overall, this project will advance our ability to precisely predict patients at risk for postpartum hemorrhage, with the investigation of novel predictors, interaction between clinical and genetic contributors, and novel application of both machine learning and polygenic risk scores to these outcomes. Ultimately, we aim to validate and implement these tools in clinical practice, leading to a greatly enhanced ability to prevent maternal morbidity and mortality. By completion of these aims, I will develop a specific skill set essential for establishing my research trajectory and transition to independence as a physician-scientist utilizing translational computational approaches to predict and improve adverse obstetric outcomes.

NIH Research Projects · FY 2024 · 2022-08

Project Summary The ability to manipulate the expression of genes in cells and organisms is foundational to the study of genetics. The CRISPR-Cas9 genome editing toolkit has revolutionized our ability to modify the genome and epigenome precisely. While CRISPR tools have been optimized to allow for robust, tunable, and predictable repression and inactivation of gene expression, approaches to induce gene expression (CRISPR activation, or CRISPRa) are less robust and reproducible. Through a combination of innovative high-throughput screens and cutting-edge computational modeling, we will develop a cohort of simple, robust, tunable, and predictable CRISPR-based tools to increase the expression of any mouse or human gene. We have developed a high-throughput sequencing-based assay system, Self-sustaining Peptide Activator Reporter-seq (SPARq), which enables quantitative screening of thousands of candidate gene activating peptides and combinations thereof to monitor and optimize their gene activation strength. In Aim 1, we will iteratively employ SPARq to systematically evaluate and optimize multiple features of gene activating peptides, including activation peptide identity, combination, linker, and CRISPRa method. We will perform SPARq screens in distinct cell types and with distinct promoter architectures to identify tools that work consistently, designing a set of CRISPRa tools that are significantly more potent and consistent than the current state-of-the- art. In Aim 2, we will improve the predictability and consequently the utility of CRISPRa through a novel high-throughput reporter assay and a computational effort to model the features associated with CRISPRa potency. We have designed an approach, CRISPR Outcome and Phenotype screening, that combines a sensitive reporter assay with a native genomic phenotypic measurement to profile the activity of a CRISPRa tool at thousands of target sites. Using data collected through this pipeline, we will develop an algorithm that takes as input one of the CRISPRa tools developed in Aim 1, a cell type, gene, and CRISPR guide RNA and outputs an accurate estimate of the expression of that gene following CRISPRa treatment. We will validate the accuracy of this algorithm to enable tunable gene activation over an extensive dynamic range in human HepG2 and K562 cells, providing it to the genetics community as a webtool. Altogether, the efforts described in this proposal will pioneer a next generation toolkit to enable more robust gain-of-function genetic manipulation and screening.

NIH Research Projects · FY 2025 · 2022-08

PROJECT SUMMARY/ABSTRACT Despite the high prevalence of metabolic dysregulation among patients with asthma, precise mechanisms driving airway inflammation in this population are not well-established. Glucocorticoids are a mainstay of treatment for asthma but damage metabolic control, increasing morbidity, and driving healthcare costs. Therefore, there is an urgent, unmet need to understand the role of metabolic pathways in asthma and the effect of targeted therapies. This proposal aims to meet that need by examining the effects of targeting the glucagon-like peptide-1 receptor (GLP-1R) metabolic pathway in patients with asthma and metabolic dysregulation. Increasing evidence supports that GLP-1R agonist (GLP-1RA) drugs reduce airway inflammation. Preliminary preclinical data also support that GLP-1RAs reduce platelet activation and mediator release, and clinically, GLP-1RAs decrease adverse cardiovascular events. Platelets are a shared source of pro-inflammatory mediators in airway and metabolic disease not addressed by current asthma therapies. Therefore, this proposal aims to test the hypothesis that augmenting the GLP-1 pathway with GLP-1RA therapy impacts clinical asthma outcomes, mediated by platelet inflammation. The long-term objective is to expand therapeutic options for patients in need of glucocorticoid-sparing interventions. Specifically, the proposed aims will 1) evaluate the impact of platelet activation on asthma exacerbations in patients with asthma and type 2 diabetes (T2DM) using an electronic health record-linked Biobank; 2) prospectively examine the effect of GLP-1RA initiation on clinical measures of airway inflammation in patients with asthma and T2DM receiving routine outpatient diabetes care; and 3) determine the impact of baseline platelet activation on clinical response to GLP-1RA treatment in patients with asthma and obesity, leveraging data from a randomized, placebo-controlled clinical trial by our collaborator Dr. Katherine Cahill. These aims directly align with the National Heart, Lung, and Blood Institute’s core scientific mission to support research that improves asthma treatment options, and additionally address the health consequences of the increasing prevalence of T2DM and obesity for the asthma population. The specific aims complement a robust training agenda for the candidate to prepare for independence and are aligned with rigorous, hands-on coursework in diabetes and metabolism, clinical study design, biostatistical analysis, and practical bioinformatics methods for clinical research, within the exceptional scientific environment at the Mass General Brigham health system and Harvard Medical School. Dr. Foer’s primary mentor, Dr. Joshua Boyce and co-mentor, Dr. Elizabeth Karlson, provide harmonized content and methodology expertise for the candidate to facilitate her professional development and research goals. A scientific advisory committee composed of experts in Pulmonology, Endocrinology, and General Internal Medicine have further committed the time, resources, and expertise to fulfill the promise of this proposal to meaningfully improve the care and health of patients with asthma.

NIH Research Projects · FY 2026 · 2022-08

ABSTRACT The transfer of patients between acute care hospitals (inter-hospital transfer, IHT) is often undertaken to provide patients with specialized care that is unavailable at the transferring hospital. Over 100,000 Medicare patients with high rates of multiple chronic conditions undergo IHT annually. However, IHT exposes patients to the risks of discontinuity of care and lacks potential safeguards that might protect against gaps in communication. Our extensive prior work examining IHT demonstrates sub-optimal transfer processes, including frequent gaps in communication and inadequate information exchange, with up to 35% of patient transfers missing essential clinical information on transfer. Sub-optimal HIE during IHT has been associated with patient harm such as therapeutic errors and delays in care and may contribute to greater mortality observed among select IHT patients. Given the complexities of this care transition, effective HIE has proven difficult to achieve due to the need for solutions to address workflow, data visualization and interoperability to be effective. The overall goals of this study are to leverage our extensive research experience in IHT and health information technology innovation to design, implement, and rigorously evaluate an intervention to improve HIE during IHT in three use cases with different levels of integration between transferring and accepting hospitals: hospitals within the same health system, hospitals in different systems that share a common EHR, and hospitals in different systems that use different EHRs. To achieve this, we propose to refine and implement an interoperable HIE platform that improves reliability of and access to necessary clinical information during IHT. We will build on our prior work that identifies essential clinical information and data visualization for effective HIE during IHT, and utilize user-centered design to rapidly identify, design, develop, refine, and implement requirements from interprofessional users, including clinicians and personnel at transferring and accepting hospitals. The HIE platform will use interoperable, data exchange standards and APIs to seamlessly integrate with existing vendor EHRs within each use case. Our team will rigorously evaluate the impact of this intervention on patient safety outcomes, including medical errors and adverse events, using interrupted time series methodology, and our team will conduct robust mixed-methods evaluation on utilization, perceived usability, and facilitators and barriers to implementation from interprofessional users who interact with the platform. Finally, these data will be presented to steering committee members with expertise in care transitions and dissemination strategy, and executive and health IT leadership from participating hospitals, to generate input on best practices for further refinement and implementation to create a dissemination toolkit to share with other similar institutions.

NIH Research Projects · FY 2025 · 2022-07

Children are not small adults; yet we heavily rely on information collected in randomized and non-randomized studies in adult populations to inform treatment strategies for pediatric patients. Historically, children have been protected from research for ethical reasons. However, this well- intentioned protection from the risks and burdens of trials has paradoxically left children more susceptible to the potential risks of drugs used in everyday practice, frequently off-label and without high-quality evidence of efficacy, effectiveness, or safety. The importance of pharmacoepidemiologic drug safety monitoring using routinely collected healthcare data has been increasingly recognized by the FDA, EMA, and other regulators, and forms the backbone for a major component of the nation’s drug safety surveillance system. However, to date, the focus of these initiatives has been on drug safety in adult populations; there is currently no systematic surveillance system targeting drug safety in pediatric populations. To address this evidence gap – which puts pediatric patients at increased risk – we propose to develop and test the performance of TreeScan based approaches for the systematic and simultaneous evaluation of multiple potential adverse outcomes in pediatric populations, and to implement these methods for prospective sequential surveillance of new pediatric medications. TreeScan methods use a hierarchical tree comprising thousands of outcomes and account for multiple testing of correlated hypotheses while systematically screening for potential adverse effects. The methodology has never been used to evaluate drug safety in pediatric patients, where there are unique challenges compared to adult populations. Thus, the methods require further development and refinement. We will test the approach based on real-world examples of established drugs with relatively well characterized safety profiles (Aim 1) as well as plasmode simulations that explore a broad range of plausible clinical contexts in pediatrics (Aim 2). The performance tested approach will then be implemented to prospectively monitor the safety of recently approved drugs and new drugs that will be approved during the early years of the grant (Aim 3). Potential signals will be further evaluated in full-scale epidemiological studies. This project will provide a critically needed tool that could lead to early detection of unsuspected adverse effects of drugs in pediatric populations if they exist and provide reassurance if no safety issues with large effects are detected. The proposed studies are expected to have an immediate and important public health impact by providing comprehensive assessments of the safety profiles for new medications in pediatric populations.

NIH Research Projects · FY 2026 · 2022-07

PROJECT SUMMARY / ABSTRACT This NIH K08 proposal, describes a five-year career development program in epilepsy genetics research. Through this program, Dr. Khoshkhoo will receive training in human genetics, the experimental and analytic aspects of next generation sequencing, and single cell genomics. This new skillset will complement Dr. Khoshkhoo’s prior research and clinical training, and ideally position him to transition to an independent investigator position studying the functional and molecular mechanisms of genetic variants in epilepsy. The institutional resources available through Brigham and Women’s Hospital (BWH), Boston Children’s Hospital (BCH), and Harvard Medical School (HMS) are world class and they provide the ideal environment to foster the career developmental of young physician-scientists. Dr. Khoshkhoo’s mentor for this proposal, Dr. Christopher Walsh (a Professor of Neurology at HMS and HHMI Investigator at BCH), is a leader in genetics and genomics of human neurologic diseases. Dr. Walsh has a long track record for mentoring other trainees to successful careers in biomedical research. In addition, Dr. Khoshkhoo has assembled a group of collaborators with complementary expertise, and an Advisory Committee with extensive experience in mentoring physician- scientists to develop independent research programs. The primary scientific objective of this proposal is to identify the role of pathogenic post-zygotic (somatic) mutations (variants) in temporal lobe epilepsy (TLE), and to characterize the cell-type specific and transcriptional mechanisms through which these variants contribute to the development of epilepsy. Dr. Khoshkhoo provides pilot data indicating that a subset of sporadic TLE cases harbor likely pathogenic somatic variants, which supports his central hypothesis that genetic and transcriptional dysregulation caused by somatic variants plays a key role in TLE pathogenesis. This proposal will systemically examine surgical TLE resections for the presence of these somatic variants and investigate their cellular and transcriptional mechanisms. To achieve these objectives, a combination of ultra-deep gene panel sequencing, Parallel RNA and DNA analysis after Deep sequencing (PRDD-seq), and single nucleus RNA sequencing (snRNA-seq) will be employed. These state of the art strategies will aim to: (1) identify pathogenic somatic variants in surgically resected hippocampal tissue from TLE patients and post-mortem neurotypical individuals; (2) determine the cell-type(s) of mutant cells in TLE cases with known pathogenic somatic variants; and (3) examine the downstream gene expression changes caused by these variants in TLE. These studies will not only help establish somatic variants as a novel mechanism for TLE pathogenesis, but also investigate their cellular and molecular mechanisms in situ. Overall, this proposal introduces a new conceptual and experimental framework for studying TLE and the findings may have immediate diagnostic and treatment implications.

NIH Research Projects · FY 2026 · 2022-07

SUMMARY/ABSTRACT Parkinson’s disease (PD), dementia with Lewy bodies (DLB), multiple-system atrophy (MSA) and certain forms of Alzheimer’s disease (AD) are ‘synucleinopathies’ - brain diseases characterized by lesions (Lewy bod- ies/Lewy neurites) rich in α-synuclein (αS). Disease-modifying treatments are not available, in part due to a lack of insight into how native αS dynamics becomes aberrant. Our long-term goal is to understand αS biology in detail and to develop strategies to preserve/reestablish the normal physiological state and function of αS. αS in Lewy bodies/neurites is often phosphorylated on serine-129 (pS129), and the kinase(s) involved have been discussed as potential drug targets. However, pS129 may also have normal physiological role at synapses sup- ported by our observation that pS129 is reversibly induced by neural activity. Our overall objectives in this appli- cation are to (i) identify the synaptic mechanisms by which activity regulates pS129, and (ii) determine the rele- vance of pS129 for αS function at the synapse. Our central hypothesis is that polo-like kinase 2 (Plk2) phosphor- ylates αS at serine-129 in response to synaptic activity, thereby fine-tuning αS function. The rationale for this project is that understanding normal synaptic αS phosphorylation is likely to offer new insight for the development of strategies to preserve αS homeostasis, correct αS imbalance and quantify signatures of αS pathology. We propose the following specific aims: 1) Identify the mechanism(s) that govern reversible αS pS129 during neu- ronal activity. 2) Identify the role of reversible pS129 in fine-tuning αS function. Under the first aim, primary rodent cortical neuron cultures will be used to confirm Plk2 as the kinase that mediates pS129 during neuronal activity and to identify molecular changes in αS and Plk2 that may trigger pS129. Key findings will be confirmed in mouse hippocampal slices and in a mouse model of enriched environment. In the second aim, we will study the effects of pS129 on αS biology functionally in vitro and in vivo. Most importantly, we will characterize S129 phospho- deficient (S129A) and -mimicking (S129D) knock-in mouse models functionally with a special focus on dopamine release, using established methods in the Sulzer lab. The proposed research is innovative, because it focuses on dynamic αS S129 phosphorylation at αS’s normal locale (the synapse of mature neurons), considers synaptic activity as an important parameter, identifies key proteins, addresses functional consequences, and extends cell culture findings to in vivo. Whereas pS129 has been widely studied, most previous work focused on its role in pathological deposits. The contribution will be significant because it is expected to provide novel, paradigm- shifting insight into normal αS biology at the synapse. Corroborating that an αS modification commonly associ- ated with disease occurs normally, and understanding how and why, is an important step towards a comprehen- sive view of αS in health and disease with major implications for drug and biomarker development. This work pursues research priorities outlined in “Recommendations of the Alzheimer's disease-related dementias confer- ence”. It focuses on priorities that address AD-related dementias (ADRD), specifically DLB and PD dementia.

NIH Research Projects · FY 2025 · 2022-07

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a major public health burden. Over 500,000 cardiac surgeries are performed annually in the U.S. alone, with as many as 64% complicated by CSA-AKI. Those who develop CSA-AKI have a 6- to 18-fold higher acute mortality compared to those without CSA-AKI. No pharmacologic therapy reliably prevents or treats CSA-AKI. Based on a strong pathophysiologic rationale from both animal models and human studies, we propose that hepcidin and other heme/iron regulatory proteins play a key role in CSA-AKI. In Aims 1 and 2, we will leverage the CABG Genomics Project, a large prospective cohort study of adult patients who underwent cardiac surgery. CABG Genomics collected detailed clinical data and biospecimens, including plasma/serum samples pre- and postoperatively at multiple time points. In Aim 1, we will measure plasma hepcidin preoperatively in 2,000 patients to test its association with CSA-AKI. We will use multivariable models to adjust for potential confounders, including plasma IL-6. We will externally validate our findings using samples from the TRIBE-AKI study, which enrolled 1219 high-risk adults who underwent cardiac surgery at 6 sites in North America. In Aim 2, we will measure plasma hepcidin, free hemoglobin, haptoglobin, hemopexin, transferrin saturation, and ferritin longitudinally in a nested 1:1 case-control study (n=600) to test whether early changes in these markers are independently associated with CSA-AKI. In Aim 3, we will enroll 250 high-risk adult patients undergoing cardiac surgery at three major hospitals in Boston. We will isolate peripheral blood mononuclear cells pre- and postoperatively to investigate the relationship between monocyte expression of ferroportin and other heme/iron regulatory proteins, examined by flow cytometry, with CSA-AKI. We will also assess whether early postoperative changes in monocyte expression of ferroportin and other heme/iron regulatory proteins are associated with CSA-AKI. Investigating the hepcidin-ferroportin-iron axis and other heme/iron regulatory proteins in the setting of CSA-AKI could have actionable implications for the design of future trials to prevent CSA-AKI. Unlike many other markers previously examined in CSA-AKI, those proposed here are directly involved in the pathogenesis of CSA-AKI and are targetable. This proposal will help determine the therapeutic strategy targeting disordered iron homeostasis that has the highest likelihood of success. If low preoperative hepcidin is confirmed as an independent risk factor for CSA-AKI, prophylactic administration of hepcidin agonists, which are currently in development, could be tested in future studies of CSA-AKI prevention. Alternatively, if the proposed studies reveal that other heme/iron regulatory proteins (e.g., haptoglobin, CD163, HO-1) have a greater influence on CSA-AKI than hepcidin/ferroportin, therapeutic strategies targeting these proteins could be tested.