University Of Florida

NIH Research Projects · FY 2025 · 2024-05

PROJECT SUMMARY/ABSTRACT Parkinson’s disease (PD) is a debilitating neurodegenerative disorder associated with the loss of dopamine producing neurons and the accumulation of protein aggregates rich in α-synuclein (Lewy bodies). While the causes of PD are not fully known, rare families with monogenic forms provide translatable targets and the models in which to test novel therapeutic strategies. For example, α-synuclein (SNCA) was discovered to be the major protein constituent of Lewy bodies only after the gene encoding it was linked to familial PD. Our discovery of SNCA multiplications subsequently provided the rationale and models to develop multiple approaches to lower αSyn expression that are currently in clinical trials. In 2014, we genetically linked a missense mutation (p.N855S) in DNAJC13 (encoding receptor-mediated endocytosis-8; RME-8) to late-onset autosomal-dominant parkinsonism in multi-incident Mennonite kindreds (RME-8 PD). Affected family members had post-mortem Lewy pathology rich in α-synuclein (αSyn) and neuronal loss in the substantia nigra (SNpc). RME-8 is a DNAJ-domain- containing protein that, together with heat shock cognate 70 (Hsc70), stimulates: 1) the refolding of misfolded proteins and; 2) clathrin removal from vesicles. Hence, loss of RME-8 leads to an accumulation of clathrin coated vesicles, hyper extended membrane tubules and the aggregation of cargos. Given this background, we developed a Dnajc13 p. N860S knock-in (DKIHet; corresponding to human p. N855S mutation) mouse model. Preliminary studies in DKIHet brain at 3 months of age reveal the RME-8 mutation: 1) increases soluble monomeric αSyn and clathrin coated intermediates; 2) causes synaptic delay following repetitive stimulation, and; 3) impairs movement initiation (resulting in freezing) in open field behavior. The phenotypes DKIHet confers are consistent with a pathologic gain of function and reminiscent of a ‘synaptopathy. In this proposal we aim to more fully characterize the DKIHet model with respect to mutant and wildtype RME-8 protein-binding in synaptosomes from microdissected striatum. We will more fully characterize differences in αSyn biology, including phosphorylated and higher molecular weight species. We will also look at the mutation’s impact on dopaminergic function, including biochemical, physiologic and morphologic assessments. Lastly, given RME-8 is also an interferon- responsive gene we will explore neuroimmune biology and focus on microglial pruning of dopaminergic terminals. Completion of these experiments will define the biologic role of DNAJC13 p.N855S, highlight its mechanism of action in disease pathogenesis, and demonstrate the utility of DKIHet mice.

NIH Research Projects · FY 2025 · 2024-05

Project Summary Type 1 Diabetes (T1D) is a disease indicated by autoimmune-mediated destruction of the pancreatic β-cells in the islets of Langerhans, which form 2-5% of the pancreas. Although the vast majority of T1D research has focused on structural and functional changes in the islets, substantial abnormalities in the exocrine pancreas also occur with this disease. Acinar cells in the exocrine pancreas synthesize, store, and secrete digestive enzymes into the duodenum. The long-term goal of this research is to understand the role of exocrine pancreas dysregulation in the pathophysiology of T1D. This proposal specifically will define changes in central carbon and lipid metabolism in the exocrine pancreas in T1D. I hypothesize that the T1D exocrine pancreas experiences increased TCA cycle turnover and de novo lipogenesis (DNL). I will test this hypothesis through two specific aims. Aim 1 will quantify changes in exocrine pancreatic central carbon metabolism in a transgenic mouse model of T1D. Aim 2 will determine rates of lipid turnover in the exocrine pancreas. The experiments outlined in Aims 1 and 2 utilize a novel pancreas perfusion method to examine exocrine pancreas metabolism. In aim 1 this is combined with nuclear magnetic resonance (NMR) spectroscopy using hyperpolarized substrates as well as gas chromatography-mass spectrometry (GC-MS) to establish the significance of TCA cycle and glycolytic flux in the exocrine pancreas in T1D pathogenesis. Aim 2 utilizes ex vivo, in vivo, and commercially available assays to investigate flux through lipid metabolic pathways and lipid storage. This research plan addresses the unmet biomedical need to understand acinar cell central carbon and lipid metabolism, thus provides critical insight on mechanisms that drive exocrine dysfunction in T1D. The knowledge gained through this work will serve as a foundation for understanding how exocrine pancreas dysregulation may affect T1D development and subsequent β-cell dysfunction. The fellowship training plan outlines three goals to accomplish my ultimate career goal of becoming an independent investigator at a tier 1 research institution: i) increase technical expertise ii) improving scientific communication and iii) engaging in mentorship. This proposal encompasses technical training in pancreas physiology, stable isotope tracing, NMR spectroscopy, GC-MS, and metabolomics analysis. The Merritt research group, the Advanced Magnetic Resonance and Spectroscopy (AMRIS) facility, and the Diabetes Institute at the University of Florida provide an exceptional environment in which to acquire these skills. Furthermore, the Merritt laboratory supports the improvement of my scientific communication and mentoring abilities. Ultimately, this training environment is ideal to engage in career development and complete the proposed research.

NIH Research Projects · FY 2026 · 2024-05

PROJECT SUMMARY/ABSTRACT Children with autism spectrum disorders (ASD) benefit from specialized services throughout their lifespan. However, autism assessment, treatment, and care are bottlenecked by clinician availability. While it is important to continue to seek to expand the ASD-healthcare workforce, recent efforts have begun to assess alternative approaches such as crowdsourcing and computational methods for their potential to accelerate and increase accessibility to the diagnostic and therapeutic process. The development and evaluation of these methods requires access to rich data on children with ASD, specifically, audiovisual recordings, i.e., videos. However, videos contain identifiable information: the face and voice of the child. Our long-term goal is to address the technical challenge of protecting facial and vocal identity for child subjects while enabling access to rich data to improve our understanding of ASD and expand availability of treatment and care. Our current objective is to elucidate the privacy-utility tradeoffs for three approaches to privatization in the use case context of behavioral assessment of children. The premise of this study is that recent strides in generative models and adversarial machine learning have yielded deep neural network architectures that can modify faces and voices to change identity; however, these architectures have been developed and tested for contexts that involve typically developing adults. We hypothesize that these architectures can be adapted to privatize video recordings of children with ASD while retaining information essential to the quantification of ASD-associated behaviors. The significance of this study comes from the value of adapting the neural network models appropriately and specifically to the autism context as this requires the preservation of attributes that would not have an equally high importance in other use case contexts. In this proposal, we will (1) generate a rich multi- camera, multi-microphone dataset of children (5-12 years old) undergoing behavioral assessment for autism, (2) determine the impact of adaptations on the efficacy of anonymization relative to baseline implementations for three classes of anonymization methods, (3) evaluate how well ASD-associated behaviors are preserved during the privatization process for the purpose of upcoming approaches to aid the diagnostic process, specifically, crowdsourced assessments and computational assessments, and (4) conduct user centered co- design to surface guidelines on making a privatization toolkit easy to use for parents and clinicians. The outcome of this study will be a framework for evaluating facial and vocal anonymization in the context of children with ASD, development of a rich and annotated shareable video research dataset for computational or behavioral investigation, evaluation of specific methods that can make rich, diverse, heterogenous data more easily available to the autism community, and development of practical, usable workflows for anonymization for care providers. More generally, this study will pave the way for worry-free video data sharing for mental health.

NIH Research Projects · FY 2026 · 2024-05

Project Summary We hypothesize that high affinity synthetic agonists of TLX may enhance adult hippocampal neurogenesis (AHN) and improve cognitive function in patients with dementia including Alzheimer's disease (AD). Here, we focus on developing, refining, and validation of TLX assays for the purposes of performing a screen for novel, synthetic TLX ligands that can be used as points to initiate drug discovery optimization efforts to develop TLX agonists towards potential clinical evaluation for treatment of dementia including AD. This is an application for a R61/R33 grant which focuses on the development and validation of assays that can be used to “identify and characterize potential therapeutic agents for neurological or neuromuscular disorders”. We are focused on identification of ligands targeting the nuclear receptor TLX that may hold utility to treat neurological disorders associated with cognitive dysfunction. The R61 phase is focused on development and validation of the key in vitro assays to identify putative TLX ligands. This is in alignment with the NIH's description of R61 activities which include (as specifically indicated in PAR-21-124): (1) Development and validation of assay(s) (including phenotypic assays) to support a succinct testing funnel…, (2) Development of in vitro or ex vivo potency/efficacy assays designed to indicate the specific ability of an agent to achieve a desired biological effect, and (3) Assay development and/or optimization for High-Throughput Screening (HTS). The R33 phase is initiated upon successful development of the assays and testing funnel and specifically is focused on (as specifically indicated in PAR-21-124): (1) HTS, comprising screening of large libraries for activity against biological targets via the use of automation, miniaturized assays and large-scale data analysis, (2) Preparation and screening of select series of therapeutic agents using…medicinal chemistry…, (3) Assessment of therapeutic agent's properties using computational analysis and early physicochemical measurements, polar surface area, solubility, cell permeability and efflux, (4) Assessment of initial in vitro pharmacokinetic parameters such as absorption, distribution, metabolism, and excretion (ADME), (5) Assessment of potential off target activities, and (5) Optimization of therapeutic agent(s) for FUTURE in vivo testing. To address these goals, we propose the following Specific Aims: R61 phase: AIM 1– Develop, refine, and validate a biochemical assay to detect TLX ligands in an HTS format and AIM 2 – Develop and validate secondary/tertiary assays for the purpose of characterizing “hits” identified in a TLX screen. R33 phase: AIM 1 – Screen both chemoinformatic driven nuclear receptor-biased chemical libraries and chemical diversity libraries using the validated assays from the R61 Phase to identify putative TLX agonists. AIM 2 – Evaluate the hits from the screens for their potential for further optimization as TLX agonists and perform initial structure-activity- relationship on priority hits. Our goal is to identify TLX agonists from multiple chemical scaffolds that will be pursued in future lead optimization studies in models of dementia and subsequently pursued in clinical studies.

NIH Research Projects · FY 2026 · 2024-05

Project Summary/Abstract Iron deficiency (ID) is the predominant cause of anemia globally. Children, menstruating and pregnant women, and the elderly are at highest risk for iron depletion. ID complicates pregnancies, impairs cognitive development in infants, and decreases work output in adults. Iron overload (IO) occurs most frequently in hereditary hemochromatosis (HH). Up to ~1:300 individuals of Northern European descent carry the most frequent mutation; 10% of these individuals are likely to develop pathological liver iron overload. HH causes arthralgia, osteoporosis, cirrhosis, cardiomyopathy, diabetes, and hypogonadism. HH results from mutations ultimately affecting production of the iron-regulatory hormone, hepcidin. Humans cannot efficiently excrete excess iron, so body iron content is maintained by modulation of intestinal iron absorption. Dysregulation of intestinal iron absorption underlies perturbations of iron homeostasis in ID and IO. Dietary iron exists mainly as heme iron (HI) and nonheme iron (NHI). Absorption of dietary NHI critically involves an iron importer (DMT1) and an iron exporter (FPN). Mechanisms of HI absorption have remained elusive. Most research in iron biology has focused on mouse models; however, mice are thought to inefficiently absorb dietary heme. To overcome this hurdle, we established a new model of HI absorption, the Sprague-Dawley (SD) rat. SD rats efficiently utilized dietary HI to normally support pregnancy, lactation, and postnatal pup development. Moreover, hepcidin (Hamp) KO rats (modeling HH) developed iron overload when fed a HI diet, thus reflecting elevated HI absorption. In this investigation, we will leverage unique dietary and genetic SD rat models of ID and IO to test novel hypotheses related to HI absorption. Our specific goals are to test: 1) Whether NHI and HI absorption is coordinately regulated. This seems likely given that intestinal iron absorption must be tightly controlled to maintain overall body iron homeostasis; 2) Whether DMT1 and FPN influence HI absorption. Heme is likely absorbed by endocytosis, followed by export from endosomes by a heme transporter. Cytosolic heme has two possible fates: a) Degradation by heme-oxygenase 1 (HMOX1), which liberates iron that then mixes with the dietary NHI pool; or b) Export out of the enterocyte via a heme exporter, followed by degradation in the liver. We hypothesize that HI and NHI transporters co-localize on plasma and vesicular membranes, thus facilitating functional interactions; and 3) Whether HRG1 is an intestinal heme transporter. HRG1 transports heme with high affinity, it is expressed on the apical surface of human duodenal enterocytes, and it is regulated by iron and heme. HRG1 is thus a plausible candidate for the long sought intestinal heme iron importer. Studies proposed herein will utilize the HRG1 KO SD rat. Collectively, the use of new dietary and genetic SD rat models of iron adequacy, ID, and IO uniquely position us to be able to address unresolved, fundamental questions relating to mechanisms of intestinal HI absorption, and to elucidate whether pathways of HI and NHI absorption intersect. Clinical and translational potential is high, as dietary HI and NHI both contribute to systemic iron homeostasis in humans.

NIH Research Projects · FY 2025 · 2024-05

The Gators Advancing Through Opportunities in Research for Aging and Alzheimer's Disease Education (GATORAADE) Program aims to expand the pool of researchers and healthcare workers interested in brain aging and Alzheimer's disease and related dementias (ADRD). The GATORAADE program will target undergraduate students in their final year and will offer a tailored postbaccalaureate program. Students will be expertly matched with research mentors aligned with their professional goals, will be provided personalized career mentorship and hands-on laboratory experience and extensive resources. Additionally, GATORAADE trainees will complete an academic curriculum that covers brain aging, ADRD, and risk factors. Our Objectives for GATORAADE trainees include:1) to develop an understanding of cognitive aging and ADRD research through mentorship, didactic instruction, and networking opportunities; 2) to enhance the trainee’s scientific efficacy via mentored hands-on research training in aging and ADRD; 3) to foster an understanding of experimental design and data interpretation in cognitive aging research; 4) to cultivate professional communication skills through research presentations at conferences; 5) to facilitate awareness of graduate and professional school alternatives tailored to the trainee’s career goals and to coach them through the application process; 6) to promote matriculation into graduate or clinical training programs related to aging and ADRD. Overall, the GATORAADE program emphasizes three core competencies: 1) Technical development of research skills in aging and ADRD, with 20 students receiving year-round hands-on laboratory training (up to two years) guided by a personalized mentorship committee; 2) Didactic instruction of foundational knowledge in aging and ADRD mechanisms through a 12-credit academic program, after which students will obtain a University of Florida (UF) Online Biomedical Neuroscience Certificate; 3) Preparation in useful scientific skills for career advancement in aging and ADRD research and related healthcare fields, including effective communication and support throughout graduate/professional school applications. The GATORAADE program aims to bridge representation knowledge gaps and enhance the workforce in brain aging and ADRD fields. By combining research experiences, academic instruction, and career development support and coaching, GATORAADE trainees will be equipped with foundational knowledge and meaningful skills to pursue graduate or clinical training programs. Retaining these individuals will contribute to reduce risk factors and to improve our chances of combatting aging related neurological conditions.

NIH Research Projects · FY 2025 · 2024-05

Summary How does the brain enable social interactions? The study of social behavior in non-human animals has long relied on coarse behavioral metrics like time spent interacting with another animal or simply the numbers of interactions. Although this approach has informed major insights into neural circuits which have a role in sociability, we still do not know how these circuits orchestrate patterns of social behaviors, especially under different social contexts where interactions have nuanced differences. Our long-term goal is to identify the neural mechanisms supporting social behavior in affiliative vs. antagonistic social contexts. To close the knowledge gap towards this goal, in this R34 we will build artificial intelligence (AI) tools that are capable of integrating multivariate sources of behavior data to quantify spatiotemporal signatures or “motifs” of diverse repertoires of social behaviors. Behavioral motifs have the potential to be captured by means of examining concurrent autonomic rhythms, especially breathing and heart rate. Indeed, we have long known that changes in the frequency of these rhythms coincide with specific affective and behavioral contexts. However, spatiotemporal signatures of social behaviors have not been captured in prior studies which have considered either breathing or heart rate in isolation. Nor have prior studies unleashed the potential to identify novel social behavioral motifs by using these autonomic rhythms in combination with video measures. The research objective of this Brain Initiative proposal is to develop semi-supervised artificial intelligence methods that result in a hierarchical multi-timescale model of social behavioral motifs directly from video, breathing, heart rate, and movement data via a head-mounted accelerometer. To accomplish this, we will use partial labels of mouse social behaviors, as well as physiologic measurements, in order to elucidate the full range of social behavior motifs across affiliative vs. antagonistic contexts. In Aim 1, we will define low-dimensional social behavioral states while incorporating autonomic rhythms, while in Aim 2, we will elucidate a multi-timescale hierarchical representation of social behavior in affiliative vs. agonistic social contexts. For both aims, we will integrate computer vision techniques with high-dimensional video and physiological data from mice while varying their isolation levels and who they are interacting with. The end-product will be a validated toolkit enabling the sensitive and robust identification of behavioral motifs. The easy-to-use toolkit which we call the Social Motif generator (So-Mo) will enable future studies to probe neural circuits during complex mouse behaviors at unprecedented resolution.

NSF Awards · FY 2024 · 2024-05

This Boosting Research Ideas for Transformative and Equitable Advances in Engineering (BRITE) Pivot grant supports research that develops new knowledge on manufacturing of gallium nitride-based heterostructures. Gallium nitride is a promising candidate for next-generation power electronics. Gallium nitride heterostructure-based electronics have been theoretically predicted to operate at higher power densities and higher temperatures with a thousand times better performance than state-of-the-art silicon technologies. However, defects generated during the heterostructure manufacturing process and self-heating during device operation are two major obstacles that limit their performance, which challenges today’s power electronics, microelectronics, and photonics. This research develops capabilities and understanding to address these challenges by developing computational tools, mechanistic understanding, and design guidelines for co-design of gallium nitride-based heterostructures, a methodology that can also be used to co-design other semiconductor devices. This highly interdisciplinary project serves as a rich intellectual and scientific training ground for graduate and undergraduate students, including students from underrepresented groups, to ensure that all students involved in the project are competitive in a multi-faceted, multi-dimensional scientific workplace. The project responds to the Chips and Science Act by contributing to the education and training of the next generation scientists and engineers in semiconductor manufacturing. The project is co-funded by the NNI Special Initiative. Nitrides such as gallium nitride (GaN) and aluminum nitride (AlN) cannot be grown from stoichiometric melts due to their high melting temperatures and high nitrogen decomposition pressures. Epitaxy is the only tool for scalable nanomanufacturing of GaN heterostructures. To epitaxially grow a GaN heterostructure with minimum defect density and thermal resistance requires precise understanding of the epitaxial growth process as well as the resulting microstructural, mechanical, and thermal transport properties. This research develops a convergent approach, building on the foundation of mechanics of materials, to holistically understand and address these challenges. It hypothesizes that (1) structural and growth parameters can be co-designed to control growth dynamics to minimize defect formation during the epitaxial growth of heterostructures, and (2) there is a collective behavior of interfaces, defects, and phonons in semiconductor heterostructures that can be optimized to minimize thermal resistance of the heterostructures. The research builds a unified simulation tool to predict and visualize highly nonequilibrium processes such as epitaxy, defect formation, and phonon scattering across length and time scales, to test the two hypotheses, and to co-design the structure and process to achieve the minimum defect density and thermal resistance for high performance GaN-based heterostructures. This research enables the co-design of structures, processes, and properties for atomically precise and scalable nanomanufacturing of a variety of semiconductor heterostructures. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2024-04

OVERALL RESEARCH STRATEGY ABSTRACT/SUMMARY Despite significant progress to reduce global malaria incidence and related deaths over the past 20 years, this positive trend is now in a state of decline. Data from 2021 indicated that the global milestones set out in WHO's global technical strategy for malaria 2016-30 (GTS) were not met, with both case and mortality targets being off track by 48%. Increasing insecticide and drug resistance, limited sensitivity of field diagnostic tools, and declining investments are urgent contributory factors to the decline in coverage and effectiveness of routine control interventions. To date, the true contribution of non-falciparum malaria (NFM) – often presenting as asymptomatic infection – to the global disease burden remains underappreciated. While P. vivax (Pv) has risen in research priority over the past 10 years, research into the fundamental epidemiology and transmission dynamics of P. ovale (Po wallikeri [Pow] and Po curtisi [Poc]) and P. malariae (Pm) has been largely neglected. Quantifying the asymptomatic malaria reservoir in human populations has been a priority topic for current ICEMR programs, yet deeper insight into this issue is elusive. The West- Central Africa Enhancing Malaria Epidemiology Research through Genomics & Translational Systems biology (Émergents [fr.]) ICEMR program leverages successful, wellestablished collaborations, unique advanced research and training infrastructures, and an extensive Sub- Saharan Africa (SSA) research network to address emerging and challenging issues in malaria transmission in the region. This Émergents ICEMR program will focus research in Nigeria and Cameroon, proposing three interwoven programmatic packages (PP): PP1. Genomic Epidemiological Mapping (GEM) of non-falciparum malaria (NFM; Pv, Po, and P. malariae [Pm]) to quantify the parasite reservoir, measure transmissibility to mosquitoes, and evaluate the insecticide resistance status of mosquitoes with NFM parasite infections; PP2. Bionomics, Ecology, & Control of An. stephensi (BECA) against the background of endemic primary and secondary anopheline vectors; PP3. Advancing Clinical and Entomological Surveillance (ACES) through emergent diagnostic and translational systems biology platforms to address emerging issues viz. asymptomatic malaria and non-falciparum malaria transmission in the context of Malaria Elimination and Eradication (MEE). Taken together, the Émergents ICEMR will (a) increase American prosperity by providing jobs at US universities to US-trained doctoral students and postdoctoral trainees as well as offer opportunities for patents, (b) strengthen US leadership and influence in the field, and (c) enhance security by developing enabling tools to tackle key public health threats posed by malaria before this disease is reintroduced into the country.

NIH Research Projects · FY 2026 · 2024-04

PROJECT SUMMARY In this project, we propose to develop primary and secondary lead small molecules into preclinical drug candidates for a precision SYNGAP1-DEE therapy. This research is consistent with the mission of NIMH because this genetic disorder impacts mental health and behavior through impairments in intellectual and social adaptive functioning. Pathogenic SYNGAP1 variants may explain up to 1% of non-X-linked neurodevelopmental disorder cases and the estimated prevalence of these mutations is similar to that of Fragile X syndrome, or 1-4/10,000 live births. Most, if not all, SYNGAP1-DEE cases are caused by variants that lead to genetic haploinsufficiency (i.e. 50% of normal protein levels). Therefore, a rational strategy to treat these patients is to develop precision-based approaches that “boost” low SynGAP protein expression in affected brain cells. In prior NIMH funded research, we developed a novel phenotypic screening platform, NDD-ChemScreen, which can detect chemical and biological agents that raise target gene/protein expression in haploinsufficient neurons. This platform was used to discover lead small molecule compounds that substantially raise SynGAP protein. Small molecules have distinct advantages compared to other approaches for genetic disorders that impact central nervous system function. They can regulate disease- driving biology, be delivered orally and still concentrate in brain tissue, and dosing can be easily adjusted to fit individual patient needs and rapidly respond to adverse effects. While these compounds currently work well in vitro, here we will optimize through established preclinical drug development workflows. This U01 research project has three specific aims. Specific Aim 1 will focus on optimizing the primary lead, SR-1815, through medicinal chemistry. We will perform extensive SAR on SR-1815 to optimize potency, efficacy, brain penetrance, solubility, and other drug-like properties (e.g., microsomal stability, CYP inhibition) to reach a primary optimized lead. Specific Aim 2 will focus on identifying and optimizing a secondary lead series for SYNGAP1-DEE with a chemical scaffold that is distinct from the primary lead. This will de-risk the overall development of small molecules for SYNGAP1-DEE by mitigating unforeseen dead-ends that can occur during development of any given chemical scaffold. Specific Aim 3 will focus on scale-up and early-stage preclinical development of one optimized lead compound (i.e. the best of the primary or secondary optimized leads). This aim will including in vitro safety pharmacology testing and end with non- GLP dose-range finding studies in two species to determine tolerability and safety. The end result of this project will be a preclinical candidate ready for IND-enabling studies, which will be a launch pad for subsequent clinical research projects aimed at improving the quality of life for patients diagnosed with SYNGAP1-DEE.

NIH Research Projects · FY 2026 · 2024-04

(PLEASE KEEP IN WORD, DO NOT PDF) Acute Kidney Injury (AKI) is a life-threatening clinical syndrome prevalent in hospitalized patients (10-15% affected), especially among critically ill patients (>50% affected). AKI patients are 6.5-fold more likely to die in the hospital and at much higher risk for developing poor long-term outcomes including incident and progressive chronic kidney disease, cardiovascular disease, and death. Early and reliable risk assessment is the key to proactive intervention and prevention. With the ever-growing availability of electronic health records (EHR), machine learning has made substantial progress in modeling the complex data for disease risk prediction including AKI. However, the majority of existing prediction models are built on data from a predefined patient cohort, also known as a global prediction model, optimized for the supposedly “average” patient. This one-size-fits-all prediction model may not work for all patients, and is especially inadequate for heterogeneous diseases such as AKI that have multiple etiologies, variable pathogenesis, and diverse outcomes. Combining patients with different etiologies in training a prediction model may hide subgroups that are more tightly associated with the clinical outcome of interest and may conceal unique pathophysiological processes specific to certain subgroups. In our previous work, we found that a global model can make completely wrong AKI risk predictions for patients in high-risk and heterogeneous subgroups. Personalized modeling is a promising alternative in which a prediction model is dynamically trained for each incoming patient by using retrospective data of an individualized cohort of similar patients. Our previous work demonstrated that personalized modeling can capture patient heterogeneity with an improved AKI risk prediction for various subpopulations, but we also identified critical challenges to address to ensure model reliability and robustness. The overall goal of this project is to develop personalized transfer learning methods to achieve equitable AKI prediction across subpopulations in the hospital setting. Specifically, we propose to develop new machine learning techniques to address two challenges in personalized transfer learning: (1) what is the best way to construct individualized patient cohort? and (2) how to avoid negative knowledge transfer during learning? Methods developed in this project are broadly applicable to other diseases and study findings can advance personalized clinical decision support for improving patient outcome.

NIH Research Projects · FY 2026 · 2024-04

Project Summary-Abstract Tumor microenvironment (TME) consists of many cell types that co-exist to promote tumor progression. Most cancer therapeutics are designed to target one molecule in one defined cell type. For example, vemurafenib (BRAF inhibitor) kills melanoma cells through targeting mutated BRAF; whereas pembrolizumab (anti-PD-1 antibody) blocks PD-1 on T cells, re-activating anti-tumor immunity. Our overarching goal is to identify targetable molecules/pathways that are critical for multiple cell types within the TME. Using the published single cell RNAseq (scRNAseq) datasets, we searched for these molecules/pathways meeting the following criteria: 1) they should have important functions in cancer cells and immune suppressive cell types such as regulatory T cells (Tregs), exhausted T cells (Texh), and myeloid-derived suppressor cells (MDSCs) etc.; 2) they are not important for effector function of major immune cells such as effect T cells (CD4+ or CD8+ Teff) or nature killer cells (NK); 3) they should be targetable with known inhibitors. NR4A1 fits all 3 criteria and represents a valid target for cancer immunotherapy. In the current proposal, we intend to use proteolysis-targeting chimera (PROTAC) technology to develop a first-of-its-kind NR4A1 degrader for melanoma therapy. Aim 1. Rational design of novel celastrol-based NR4A1-Ps by modifying celastrol and linkers. Aim 2. Determine cellular and molecular mechanisms by which NR4A1-Ps work to inhibit melanoma. Aim 3. Explore the therapeutic potential of NR4A1- Ps as a single agent or in combination. The outcome is to define the rationale for the future clinical translation of NR4A1-Ps to enhance ICI therapy responses in melanoma.

NIH Research Projects · FY 2025 · 2024-04

PROJECT SUMMARY Candidate and Environment: Dr. Rana’s career objective is to establish an independent research program aimed to develop therapeutic strategies to enhance respiratory function following spinal cord injuries (SCIs). This proposal has been carefully designed to supplement the candidate’s strong background in SCI neurobiology and respiratory neurophysiology with the acquisition of additional technical skills to study neuromodulatory therapies in rodents and will make her ideally suited to succeed on her career path. The University of Florida is an ideal place for Dr. Rana to achieve these goals since it is home to the Breathing Research and Therapeutics Center which brings together basic and clinician scientists devoted to understanding and addressing physiological challenges of respiratory motor control in disease and injury conditions. The core mentoring team consists of Dr. David Fuller (scientist) and Dr. Emily Fox (clinician-scientist), who are leaders in the field of respiratory motor control and SCI rehabilitation, and have a track record of successful mentees. Research: Respiratory complications are a leading cause of morbidity and mortality in the SCI population. Thus, strategies to target respiratory motor recovery are urgently needed. Transcutaneous spinal direct current stimulation (tsDCS) is a non-invasive neuromodulatory therapy that involves the delivery of a constant low-intensity current to target neural tissue, resulting in increased activation of spinal pathways and motor neuron excitability. However, the feasibility and efficacy of tsDCS to restore breathing following SCI has never been investigated. We have recently demonstrated that ampakines (allosteric modulators of α-amino-3-hydroxy-5- methyl-4-isoxazolepropionic acid (AMPA) receptors) enhance diaphragm muscle activation at acute and chronic stages of SCI. Thus, we hypothesize that 1) tsDCS can safely stimulate diaphragm motor output after incomplete cervical SCI, and 2) pairing tsDCS with low-dose ampakine promotes neuroplasticity, and therefore, is an effective respiratory neurorehabilitation approach. We will use a multidisciplinary approach, including controlled neurophysiological phrenic nerve preparations (Aim 1 & 2) and a comprehensive system to quantify diaphragm activity and overall ventilation in awake/unrestrained rats (Aim 3 & 4) to accomplish the following aims: 1.) Develop an effective tsDCS protocol to increase phrenic activation after cervical SCI; 2.) Test whether pairing ampakine therapy with tsDCS will promote sustained increases in phrenic output; 3.) Test whether tsDCS paired with ampakines can safely enhance diaphragm EMG output in awake rats with cervical SCI; 4.) Test whether a rehabilitation paradigm, consisting of daily tsDCS + low-dose ampakine therapy, can promote sustained recovery of diaphragm activation after cervical SCI. This application encompasses both mentored and independent phases. For the mentored phase of this application, a strong scientific community and support structure has been set in place. Together the co-mentors will guide the candidate in developing the necessary skills to complete this work and transitioning into a career aimed at developing effective strategies to mitigate SCI-inducted motor dysfunction.

NIH Research Projects · FY 2025 · 2024-04

TH17 cells are a subset of CD4+ T cells that are important for immune responses to extracellular pathogens and fungi, however, they can become dysregulated and lead to autoimmunity and chronic inflammatory conditions, such as inflammatory bowel disease (IBD). TH17 cells secrete a myriad of pro-inflammatory cytokines, including IL-17A, IL- 17F, IL-21, and IL-22, which give them a dynamic range of pathogenic potential. This could explain why IL-17A/IL- 17R-neutralizing antibodies have had limited success in treating IBD, while targeting cell-intrinsic factors that broadly regulate the TH17 cell phenotype may be more effective. Modulating the development of TH17 cells through intracellular transcription factors (TFs) like NRs provides an approach to lessen multiple components of the inflammatory response responsible for IBD, avoiding some of the pitfalls of current therapies. Our preliminary data is consistent with previously published literature describing the orphan nuclear receptor NR2F6 as a negative regulator of pro-inflammatory cytokines implicated in IBD, including IL-17A and TNF. Genetic experiments have demonstrated loss of NR2F6 enhances T cell effector responses, leading to increased sensitivity to autoimmune and chronic inflammatory diseases, making it an attractive target for therapy. NRs act as ligand regulated TFs that can activate or repress transcription of target genes through recruitment of various co-factor molecules. Additionally, these co-factors can recruit chromatin remodelers, adding another layer of transcriptional regulation. Little is known about NR2F6’s transcriptional and ligand-regulated function at the molecular level. The overarching goal of this project is to elucidate NR2F6’s mechanism of transcriptional regulation in TH17 cells and determine how this may influence TH17-mediated diseases, including IBD. My first aim is to enumerate NR2F6’s transcriptional function in TH17 cells. This will be done through integration of NR2F6 overexpression models using CUT&RUN footprint analysis and RNAseq to identify genes potentially modulated by NR2F6; RNAseq and ATACseq of NR2F6 knockout TH17 cells will be used to identify NR2F6 target genes and its capacity to remodel chromatin at these gene loci. Co-immunoprecipitation (CoIP) studies will determine the co-factors NR2F6 recruits to regulate transcription. Integration of this Multi-OMICS data will provide a comprehensive mechanism for NR2F6’s transcriptional activity. My second aim is to define how small molecules affect NR2F6 transcriptional activity and function in TH17 cells. Previous efforts by our lab have identified a synthetic NR2F6 ligand. RNAseq and multi- parametric flow cytometry will be used to characterize and validate the effects of treatment with this ligand. Additionally, Co-IP proteomic studies will identify ligand-dependent changes in NR2F6 co-factor recruitment that may lead to changes in function. We hypothesize that NR2F6 serves as a critical negative regulator of TH17 cell effector responses and NR2F6 small molecule ligands can be used to further explore its biology.

NIH Research Projects · FY 2026 · 2024-04

SUMMARY The goal of our studies is to understand RORα’s role in the transcriptional regulation of TH17 cell pathogenicity and chronic inflammation. RORα is a member of the ligand-regulated nuclear receptor (NR) superfamily of transcription factors. Significantly less is known about RORα in the transcriptional regulation of TH17-mediated immunity. We and others recently published RORα is required for full TH17-cell development, particularly in mouse models of chronic inflammation. Despite this evidence, RORα is considered functionally redundant to RORγt, the lineage defining transcription factor of TH17 cells. As ligand-regulated transcription factors, NRs evolved to respond to endogenous small molecules, translating these signals into changes in gene expression. Synthetic small molecules can also be utilized to understand receptor function. Our data suggests that RORα/ligand-regulation may protect from chronic inflammation, including colitis. Given the evidence that both intra- and extra- cellular ligands regulate NR activity in TH17 cells, defining RORα and ligand mechanisms of action is key to understanding signaling pathways underlying homeostasis vs. pathogenesis. Therefore, understanding these processes may be essential to understand how RORα contributes to TH17 cells and disease. Our overarching goals are to elucidate the mechanisms that regulate RORα’s transcriptional activity and interacting partners, thus driving functionality in TH17 cells during inflammatory processes. Understanding RORα’s transcriptional role in TH17 cells may reveal a novel therapeutic option for the treatment of TH17-mediated chronic inflammatory disorders. We will achieve our goals by: 1) establishing how RORα transcriptionally promotes and maintains pathogenic TH17- mediated inflammation and 2) using pharmacological approaches to understand how ligands affect the transcriptional activity of RORα in TH17 cells. Collectively, our studies will uncover important transcriptional roles for RORα in TH17 cell biology and reveal whether targeting RORα may be advantageous for the treatment of TH17-mediated chronic inflammation.

NIH Research Projects · FY 2026 · 2024-04

Abstract: Ewing’s Sarcoma (ES) is the second most common pediatric bone cancer. Intensified chemotherapy regimens have only incrementally improved recurrent or metastatic ES outcomes, motivating research and development of new treatment options to combat this deadly disease. The accumulation of large glycogen granules, clinically known as Periodic acid-Schiff (PAS) positive, is a clinical hallmark of ES. However, the origin and pathology of ES-glycogen remains a critical knowledge gap and it has not been pursued as a therapeutic target. Recent reports, including our own, reveal critical roles for complex carbohydrates such as glycogen and N-linked glycans in tumor progression. We developed a robust and highly sensitive workflow called MALDI imaging of complex carbohydrates (MICC) in situ with near single cell spatial resolution. Using this workflow, we interrogated complex carbohydrates in over 1000 tumor specimens from prostate, lung, colon, and ES patients. Our data demonstrate that: 1) high glycogen is a unique clinical hallmark of ES; 2) three independent strategies (i.e., CRISPR knockout, small molecule inhibition, and genetic re-expression) led to dramatic reduction of ES glycogen and resulted in blunted ES tumor growth in vivo in athymic mouse models; 3) a glycogen synthase inhibitor synergized with metformin at improving AMPK activity and preventing tumorigenesis. Collectively, these results provide strong evidence to support our hypothesis that glycogen is a unique and clinically actionable hallmark of ES that can be leveraged in the clinic for both diagnostic and therapeutic interventions. The objective of this study is to define the role of glycogen in ES clinical outcomes, cancer metabolism, and leverage glycogen targeting strategies as therapeutic options for ES. To achieve this, we will: Define diagnostic and predictive potentials of glycogen in ES clinical course. (Aim 1). Then, we will Define spatio-cellular roles of ES glycogen utilization to support cancer growth. (Aim 2). Finally, we will assess Glycogen as an ES therapeutic target. (Aim3). Our study presents a pioneering, integrated approach to explore the distinct ES hallmark of excessive glycogen using powerful methodologies like mass spectrometry imaging and unique clinical cohorts of ES tumors. This proposal builds on the foundation of exciting preliminary data and our transdisciplinary team's expertise to define the ES clinical course, understand ES tumor metabolism, and improve treatment of documented disease. Our findings will substantially enrich the knowledge base, spurring the development of personalized therapies for ES patients who currently rely solely on conventional chemotherapies. Our goal is to improving patient care outcomes and provide better treatment options for children suffering from ES.

NIH Research Projects · FY 2026 · 2024-04

PROJECT SUMMARY (See instructions): RELEVANCE (See instructions): PROJECT/PERFORMANCE SITE(S) (if additional space is needed, use Project/Performance Site Format Page) Project/Performance Site Primary Location Organizational Name: DUNS: Street 1: Street 2: City: County: State: Province: Country: Zip/Postal Code: Project/Performance Site Congressional Districts: Additional Project/Performance Site Location Organizational Name: DUNS: Street 1: Street 2: City: County: State: Province: Country: Zip/Postal Code: Project/Performance Site Congressional Districts: PHS 398 (5HY$SSURYHG7KURXJK) OMB No. 0925-0001 Page 2 Form Page 2 Square, Tyler A The overall dental morphology of an adult vertebrate is set in motion by the initiation of tooth fields at specific regions in the body plan during early development. Thereafter, primary teeth form sequentially, expanding each tooth field as new teeth are added at the tooth field margin. Basic research into the genes and signaling pathways underlying these processes will reveal which cell types and genetic signatures are associated with tooth field initiation and expansion, thus informing future attempts to create and successfully implant live teeth. By determining which cell types are capable of undergoing transformation to a dental fate, new avenues for the creation of lab-made tooth organs will be revealed. Additionally, identifying the genetic signatures associated with tooth field expansion and arrest will provide information about the greater context under which dental arcade expansion is facilitated. The present study will use a newly developed set of stable transgenic stickleback fish and zebrafish to identify the cell types, transcript profiles, and signaling events that underlie the processes of tooth field initiation, expansion, and arrest. These model fishes present a unique opportunity to understand tooth field morphogenesis, because tooth field position and size can be manipulated using genetic tools. In response to Eda overexpression, both species form ectopic tooth fields in highly consistent locations in or on the head, while also expanding endogenous tooth fields. By contrast, Dkk2 overexpression in stickleback reduces tooth field size by inhibiting tooth field expansion. Aim 1 seeks to understand the gene expression dynamics of the switch to a tooth organ fate by assessing the fine spatial expression patterns of genes encoding Tumor Necrosis Factor Receptors (TNFRs), candidate receptors that may confer the response to Eda, and performing single-cell RNA sequencing on tooth-competent regions microdissected from Eda overexpressing and WT sticklebacks. Aim 2 of this project seeks to find gene expression differences associated with regenerative vs non-regenerative teeth. Aim 3 will elucidate which developmental pathways are associated with tooth field size and tooth row number by comparing the gene expression profiles of the dissected tooth field margins derived from expanded (Eda overexpression), arrested (Dkk2 overexpression), and normal stickleback tooth fields. Overall, these experiments will yield information on how teeth can be specified (Aim 1) or regenerated (Aim 2), and which gene expression responses are concomitant with favorable or

NIH Research Projects · FY 2025 · 2024-03

Recent outbreaks of arboviral diseases such as Zika and West Nile have their roots in forested ecosystems. Their emergence and spread often coincide with agricultural land conversion, which alters arthropod vector communities and the wildlife reservoirs that sustain zoonotic transmission. Our ongoing epidemiological studies in Florida demonstrate the circulation of multiple understudied arboviruses in humans, wildlife, and livestock, including Everglades virus (EVEV), a zoonotic alphavirus closely related to Venezuelan equine encephalitis virus. Across Florida’s growing network of small farms, open pasture systems and crop operations coexist with agroforestry and other sustainable practices. Despite the accelerating adoption of agroforestry, its impacts on infectious disease risk remain poorly characterized. This research aims to fill that gap by investigating zoonotic arboviral transmission in Florida in relation to agricultural practices, including agroforestry. Various factors, from biodiversity shifts to land tenure benefits and irrigation schemes, likely influence disease transmission. We hypothesize that landscapes that merge forest, agriculture, and human dwellings may enhance zoonotic arbovirus transmission by increasing overlap among vectors, vertebrate reservoirs, and humans. Our first aim is to assess agroforestry’s impact on zoonotic arboviral risk among the agrarian population in Florida by conducting serosurveys of farming households. Participant interviews will provide data on health and social determinants relevant to agriculture and zoonotic interactions. These data will inform habitat suitability modeling. Our second aim is to characterize vector ecology, infection rates, and host use across an agricultural gradient. We will quantify vector assemblages in agroforest interiors, boundaries, and open farm environments, and employ multiple trapping approaches to measure viral transmission and determine blood meal origins, to shed light on shifts in host usage associated with agroforestry. Our third aim is to map zoonotic arboviral risk using geospatial and field data. We will also evaluate natural selection and gene flow of EVEV across the agricultural gradient using genomes from field-collected mosquito, wildlife, and human isolates, along with historical regional sequences, to test the hypothesis that elevated host diversity at forest–agriculture interfaces promotes greater viral genetic diversification. The outcomes of this research will define the transmission dynamics and health burden of important zoonotic arboviruses in Florida and support evidence-based prevention strategies. This knowledge will guide land use and health policies, inform interventions, and help align extreme heat resilience and public health objectives within the context of agroforestry. The methodologies and insights generated will have broad applicability across regions with similar ecologies. Modified

NIH Research Projects · FY 2026 · 2024-02

Project Summary DNA-encoded library (DEL) technology has revolutionized the discovery of protein- binding small molecules. We have developed a novel variant of this technology in which the libraries are synthesized on tiny, hydrophilic beads using solid-phase synthesis techniques and screened by incubation with fluorescently labeled, soluble proteins. This platform will be employed to discover a plethora of new ligands for the proteasome and other proteins involved in the Ubiquitin Proteasome System (UPS). They will serve as probe molecules and drug leads for manipulating the UPS, which is critical for maintaining protein homeostasis. An additional outcome of this work will be the development of a new class of degraders that delivers a target protein directly to the proteasome without the requirement for target Ubiquitylation. Finally, a nascent system that allows screening DELs in cell-based assays will be optimized and utilized to discover proteasome activators that can be used to test models of UPS dysfunction as a root cause of aging and various degenerative diseases.

NIH Research Projects · FY 2026 · 2024-02

PROJECT SUMMARY/ABSTRACT: Kidney disease is a major contributor of death in the U.S. Chronic inflammation is common among individuals with chronic kidney disease. A diet high in salt or low in potassium is associated with increased inflammation and kidney injury. The renal handling of salt and potassium within distal segments of the nephron is linked to the circadian clock. Recently, distal segment cells have been linked to initiating tubulointerstitial inflammation. The research goal is to determine the mechanistic links between BMAL1 and activation of the immune system within distal segment cells of the kidney. Preliminary data identifies BMAL1 as a driver of inflammation in the kidney in response to a low K+/high salt diet, leading to kidney injury. Studies will use novel conditional knockout mouse models to reduce expression and re-express BMAL1 specifically in distal segment cells. The first aim will test the hypothesis that mice with decreased BMAL1 expression within distal segments display lower immune mediated kidney damage in response to low potassium with high salt diet. The second aim will test the hypothesis that BMAL1 within distal segments stimulates pro-inflammatory cytokine production in mice fed a low K+/high salt diet. To test these hypotheses, experiments to determine the localization and extent of renal injury, cytokine/chemokine production, immune cell recruitment and activation in response to a low K+/high salt diet are planned. These studies will establish a novel line of investigation aimed at understanding the link between the clock gene BMAL1 and activation of the immune system in the kidney. The long term goal of this work is to The training plan was carefully designed to build upon career development skills of the project leader focused around research advancement, education, and service to the scientific community. The experiments and career development will take place at the University of Florida, a top ten public research university that provides an outstanding environment for conducting biomedical research. Together, data from this award will provide a foundation for identifying new targets to treat renal inflammation/injury in order to improve the quality of life in individuals with kidney disease. The mentored training plan will provide the project leader with necessary technical and professional skills training needed to become an independent investigator.

NIH Research Projects · FY 2026 · 2024-01

PROJECT ABSTRACT/SUMMARY In 2018 alone, the WHO reported 1.7 million new cases and estimated 770,000 HIV-related deaths due to gaps in HIV services. Early detection of HIV would allow quicker intervention and can significantly reduce the risk of death and further transmission. Therefore, this proposal aims to develop an innovative engineered CRISPR/Cas-based automated self-testing diagnostic platform for early detection of HIV RNA. The type V and VI CRISPR/Cas systems when bound with their specific target sequence, activate a secondary collateral nuclease activity that can rapidly cleave single-stranded nucleic acids in a non-specific multiple-turnover manner. By monitoring the collateral activity of CRISPR/Cas systems using a FRET-based reporter, picomolar concentrations of a target can be detected. Jain lab (PI) discovered that 3'-end extensions of CRISPR RNAs with a short 7-nt DNA, drastically enhances the collateral nuclease activity of LbCas12a by 3.2-fold and termed it ENHANCE. By applying ENHANCE femtomolar concentrations (700 fM) of HIV-1 target gene was detected in 30 min without requiring any target pre-amplification (Nat. Comms., 2020 & Methods, 2021). The Jain lab developed a lyophilized version of ENHANCE v2, which is stable up to 30 days at room temperature and in combination with an isothermal DNA amplification step, achieved a limit of detection of 15 copies/µL of SARS- CoV-2 RNA with ~97% sensitivity and ~97% specificity in patient samples within 50 minutes (Comms. Med., 2022). The PI recently developed a thermophilic BrCas12b-based single-pot SPADE assay to detect SARS- CoV-2 in saliva using a point-of-care device (eBioMed., 2022) and an engineered BrCas12b-based SPLENDID assay to detect HCV RNA in serum extracted with magnetic beads (Cell Rep. Med.-in revision, 2023). Based on the preliminary data, the exploratory R61 phase will have the following specific goals. 1) To enhance sensitivity and specificity of CRISPR/Cas systems to detect 1000 copies of RNA in 1 mL of plasma without the need for an isothermal DNA amplification step. 2) To develop an automated integrated microfluidic device for sample preparation, extraction, and detection of a HIV-1 target by naked eye at 1000 target copies/mL concentration. 3) To perform a pilot study with the optimized device for validating HIV-1 RNA detection in clinical plasma samples from healthy (n=60), and HIV-infected (n=60) with 95% accuracy. Only after achieving these milestones, the project will transition into the R33 phase with the following specific aims: 1) To recruit and survey 200 participants for user acceptability and usability of the device. 2) To perform clinical assessment of the self- testing platform with 200 participants. This integrated approach will have all the components as defined by the ASSURED (Affordable, Sensitive, Specific, User-friendly, Rapid and robust, Equipment-free and Deliverable to end-users) criteria by WHO. The development of this rapid self-testing platform would allow quicker interventions, reduced outbreak and ultimately reduced deaths in people infected with HIV.

NIH Research Projects · FY 2026 · 2024-01

PROJECT SUMMARY/ABSTRACT Pulmonary arterial hypertension (PAH) is a fatal and progressive disease with unknown etiology and poor survival rate. Pulmonary vasoconstriction, vascular remodeling and occlusive intimal lesion are the major causes for the elevated pulmonary vascular resistance (PVR) in PAH. A rise in cytosolic Ca2+ concentration ([Ca2+]cyt) is a trigger for pulmonary arterial smooth muscle cell (PASMC) contraction (and vasoconstriction) and a stimulus for PASMC proliferation/migration (and vascular remodeling). In addition, the contractile-to-proliferative phenotypic transition (CPPT) in PASMC and endothelial-to-mesenchymal transition (EndMT) in pulmonary arterial endothelial cells (PAEC) are implicated in the development of pulmonary vascular remodeling and obliterative intimal lesion in PAH. We recently found that Piezo1, a mechanosensitive cation channel, and CALHM1 (calcium homeostasis modulator 1), a voltage-gated cation and ATP channel, are upregulated during CPPT and involved in vascular remodeling in PAH/PH. Upregulated Piezo1 in PAEC enhances EndMT via the Ca2+/AKT/mTOR-Jagged1 (Jag-1) signaling axis and is involved in the development of occlusive vascular lesion and concentric vascular remodeling in animals with experimental pulmonary hypertension (PH). In addition, we identified GPR91 (a succinate-activated GPCR) and GPR68 (a mechanosensitive GPCR) that are involved in the development of pulmonary vascular remodeling in PAH/PH. The central hypothesis is that ionic (channel) remodeling is required for phenotypic transition of PASMC/PAEC. Upregulated channels (Piezo1/CALHM1) and receptors (GPR68/91) are required for causing pathogenic overgrowth of PASMC/EC through activation of Ca2+- sensitive signaling and compartmentation of AKT/mTORC1 signaling, and contribute to vascular remodeling and occlusive intimal lesion in PAH. The overall goals of this study are to examine: 1) gene expression profile associated with the phenotypic transition of PASMC (CPPT) and PAEC (EndMT), 2) cellular and molecular mechanisms involved in CPPT in human PASMC, 3) whether Piezo1 and mechanosensitive Ca2+ signaling contribute to inducing and regulating EndMT in PAEC and whether endothelial Piezo1 is involved in the development of PH, 4) how compartmentalized AKT/mTORC1 signaling and spatiotemporal Ca2+ signaling are involved in EndMT in PAEC and enhanced PAEC proliferation in PAH/PH, 5) whether viroporins (e.g., SARS- CoV-2 E protein) form non-selective cation channels to promote Ca2+ influx and stimulate PASMC/EC proliferation, and 6) whether and how Ca2+ influx through upregulated cation channels and activation of selected receptors contribute to regulation of inflammasome in PASMC/EC. The importance of this research program is in its integrative design and translational potential in which we will define the pathogenic mechanism, identify new therapeutic targets, and develop novel therapies for PAH/PH based on our studies on mechanosensitive channels/receptors and Ca2+ signaling in PASMC and PAEC.

NIH Research Projects · FY 2026 · 2024-01

Project summary The mechanisms by which cigarette smoke (CS) activates the complement cascade to cause distal lung sterile injury and progression to COPD are not completely understood. Considering the critical role of complement in pathogen-induced inflammation, selective inhibition of the lectin complement pathway may result in decreased CS-induced emphysema-like airspace enlargement without an indiscriminate inhibition of complement’s response to pathogens. In Aim 1 we propose to investigate a novel mechanism of CS-induced lung injury, focusing on members of the lectin complement pathway that are necessary to induce complement deposition in the lung, decreased type-2 alveolar epithelial (AT2) cell proliferation and differentiation into AT1 cells, resulting in emphysema. In Aim 2 we will investigate whether decay accelerating factor (CD55), a complement regulator is necessary and required to protect against lectin complement deposition on AT2, preventing cell injury and improving AT2 proliferation / differentiation. In Aim 3 we propose a translational approach to develop a plasma complement activity score encompassing complement proteins and their regulators that could identify emphysema progression in smokers at risk and early COPD individuals. My proposal addresses the clinically relevant question whether harnessing membrane CD55 expression and signaling in AT2 cells can prevent lectin complement deposition and improve AT2 proliferation and differentiation mitigating emphysema development. Our ex-vivo and in-vivo murine studies are accompanied by measurements of complement proteins and regulators levels and activity in plasma from active smokers with and without COPD enrolled in COPDGene using a multiplex proteomic platform, SomaScan. Multiple complement SomaScan proteins are used to develop a “complement activity score” to help predict emphysema progression. Completion of this project will provide compelling experimental evidences that targeting lectin pathway activation and preserving membrane CD55 expression on AT2 cells ameliorates distal lung injury in murine models of emphysema and it can be harnessed as next generation biomarkers in human COPD disease. Our newly complement activity score could identify smokers at risk and early COPD subjects in future research and pharmacological clinical trials. The complementary expertise of our team, the translational aspect of the proposal, and access to well-phenotyped human specimens increase the relevance and chance of successful completion of this project.

NIH Research Projects · FY 2025 · 2024-01

ABSTRACT To better diagnose and treat individuals at risk for age-related dementia and cognitive decline, it is important to understand the differences between normal and pathological changes to the brain and their different impacts on cognitive function. Furthermore, the presence of different cognitive trajectories across the normal spectrum of brain aging presents a particularly challenging problem for cognitive science and clinical treatment efficacy. The objective of this research proposal is to identify age-related changes to brain function across cognitive trajectories in different types of learning. Although it has been long documented that humans and other mammalian species exhibit behavioral shifts from ‘place/allocentric’ to ‘response-driven/body- centered’ spatial navigation strategies in advanced age, it is unclear whether these shifts extend to strategy use in other cognitive domains outside spatial learning. This response shift has been defined by shifting away from hippocampus (HPC)-dependent ‘cognitive mapping’ strategies, and toward caudate nucleus/dorsal striatum-dependent ‘stimulus-response’ strategies. Furthermore, the dorsomedial subregion of the dorsal striatum (DMS), has been implicated in behavioral flexibility and age-related changes to goal-directed behavior. These observations suggest overall age-related changes to network communication that reflect the relative expression of HPC- versus DMS-dominant solutions. This proposal will test the central hypothesis that age- related changes to learning strategy are a product of suboptimal, perseverative behavior that can manifest as cognitive impairment in older adults across different behavioral tasks, that this deficit is reflected by altered HPC-DMS network activity, and that the anterior cingulate cortex (ACC) plays a critical role in these dynamics. To achieve the goals of this proposal we will first combine high density in vivo electrophysiology recorded from the HPC and DMS during associative and spatial learning in young and aged animals. This aim will determine whether aged impaired or unimpaired animals have differential coupling patterns between the HPC and DMS compared to young, and in what cognitive contexts these differences arise. Second, we will determine the contributions of the ACC on spatial learning in young and aged rodents combining neurophysiology, volumetric mapping of immediate-early gene expression, and circuit manipulation using virally transfected designer receptors. The findings of this proposal will begin to unravel a more complex view of memory-system interaction and age-related cognitive decline, which will have implications for therapeutic strategies in treating dementia and promoting cognitive health.

NIH Research Projects · FY 2026 · 2024-01

Project Summary The release of Ca from the sarcoplasmic reticulum (SR) via the ryanodine receptors (RyR2) regulates the heartbeat. This Ca release process is tightly controlled in healthy hearts but goes awry in diseased hearts due to genetic or acquired defects of the RyR2 channel complex. These defects typically make the channel complex hyperactive or leaky, thus giving rise to aberrant Ca release (ACR). While the harmful role of RyR2-mediated ACR is well-established in a spectrum of cardiac pathologies, much less is known regarding how ACR is translated into a specific disease phenotype. For instance, ACR is associated with both arrhythmias and cell death in heart failure and metabolic heart diseases. However, in settings of catecholaminergic polymorphic ventricular tachycardia (CPVT), a genetic arrhythmia syndrome due to mutations in RyR2 or its accessory proteins, ACR results in arrhythmias without signs of pathological remodeling. Mitochondria are involved in myocyte Ca homeostasis to regulate energy production but also cell death. Intriguingly, our recent study provided evidence that mitochondria behave as an efficient Ca sink in the setting of CPVT, which appears to be critical to mitigate detrimental consequences of ACR. Interestingly, this protective Ca-absorbing role seems to be unique to CPVT mitochondria. In contrast, in wild type and several other disease models enhancing mitochondrial Ca uptake stimulates the emission of reactive oxygen species (ROS) and exacerbates RyR2 leak and arrhythmias. These studies suggest that mitochondria play a key role in translating ACR into a specific pathophenotype. They also raised important questions as to why mitochondria in CPVT act as a protective Ca sink and how that impacts Ca-dependent arrhythmias. Based on data in the literature and our preliminary results, we hypothesize that protective changes in CPVT mitochondria alter SR-mitochondria interplay to shape diastolic Ca signal and impact Ca-dependent arrhythmias. Specifically, we propose that in CPVT a dynamic phosphate (Pi)-based mitochondrial Ca handling mechanism converts mitochondria into a protective Ca sink so they can absorb ACR; in parallel, tethering (physical contacts) between mitochondria and SR, also known as mitochondria-associated-membranes (MAMs) are promoted in CPVT to facilitate SR-mitochondria Ca transfer. Thus, we propose that modulating the Pi-based mitochondrial Ca handling, as well as SR-mitochondria tethering both impacts arrhythmogenesis. We have designed multiscale studies (from molecule to whole animal) that employ novel genetic mice models/adeno-associated virus (AAV) 9-mediated gene transfer. We will utilize methods of cellular physiology, protein biochemistry, and in vivo cardiac functional assays to test our hypothesis. The proposed studies will help us gain a better understanding of protective molecular changes of CPVT mitochondria, thus not only benefitting the design of mechanism-based therapies for CPVT, but also providing clues for the development of therapies for a range of Ca-dependent cardiac dysfunctions that are linked to ACR.