Wayne State University

NIH Research Projects · FY 2025 · 2021-01

ABSTRACT Metabolic reprogramming is an important hallmark of cancer. Of the altered metabolic pathways associated with malignancy, one-carbon (C1) metabolism is particularly notable. The 3-carbon of serine is the major C1 donor for de novo synthesis of purines and thymidylate in the cytosol, and the primary catabolic pathway for serine and synthesis of glycine occurs in the mitochondria. The mitochondrial C1 pathway also generates reducing equivalents and is an important source of ATP. The first enzyme of the mitochondrial C1 pathway, serine hydroxymethyltransferase (SHMT) 2, is an oncodriver which is upregulated in a substantial number of cancers. Growing evidence suggests that SHMT2 could be an independent prognostic factor and an important therapeutic target for cancer. We discovered novel 5-substituted pyrrolo[3,2-d]pyrimidine compounds AGF291, AGF347, and AGF359. Following their internalization by the proton-coupled folate transporter (PCFT), these compounds inhibit mitochondrial C1 metabolism at SHMT2, with direct secondary inhibitions of cytosolic targets in de novo purine (DNP) biosynthesis (at 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase and glycinamide ribonucleotide formyltransferase) and SHMT1. Our compounds inhibit proliferation of epithelial ovarian cancer, non-small cell lung cancer, colorectal cancer, and pancreatic cancer (PaC) cells, suggesting their potential as broad-spectrum anti-tumor agents. AGF347 exhibited significant in vivo antitumor efficacy with potential for complete responses against both early and upstage PaC xenograft models. We posit that our novel compounds offer an entirely new approach for treating cancer. Our objective is to optimize our lead structures for tumor targeting via PCFT and inhibition of mitochondrial and cytosolic C1 metabolism at modest doses with minimal toxicity. We will use PaC as a disease prototype for further development of our novel multi-targeted inhibitors. In Aim 1, we will synthesize up to 100 compounds based on lead compounds to optimize uptake by tumors, and inhibition of SHMT2 and cytosolic pathways including DNP biosynthesis. In Aim 2, we will test analogs from Aim 1 for antitumor potencies toward clinically relevant PaC cell lines, tumor selectivity and plasma membrane and mitochondrial drug transport, drug metabolism, and inhibition of SHMT2 and cytosolic pathways including DNP biosynthesis. We will measure downstream impacts on mTOR signaling, mitochondrial respiration, glutathione pools, and reactive oxygen species. In Aim 3, we will evaluate pharmacokinetics, tolerability, and in vivo antitumor activities of compounds from Aims 1 and 2 by toxicity/efficacy trials with human PaC cell line xenograft and PDX models, and with the KPC mouse PaC model. Our lead analogs are “first-in-class” and our proposed studies will afford optimized compounds with the best balance of selective tumor targeting and anti-tumor efficacy, resulting from inhibition of SHMT2 and downstream anabolic pathways. We anticipate developing SHMT2/DNP-targeted compounds for IND submission and clinical trials based on our studies.

NIH Research Projects · FY 2025 · 2021-01

7. PROJECT SUMMARY/ABSTRACT Impaired diastolic relaxation, an important component of diastolic dysfunction, is present in nearly all patients with heart failure-both with reduced and with preserved ejection fraction- and is present in nearly 25% of asymptomatic individuals. Unfortunately, no treatments for impaired relaxation exist. Recently, my lab identified and defined Mechanical Control of Relaxation as a faster relaxation rate in response to the rate of a lengthening strain. In other words, the relaxation rate is sensitive to the strain rate of the myocardium. Our data demonstrate that this mechanical regulation of relaxation can increase the relaxation rate two-fold beyond the biochemical processes that limit myosin detachment from actin, including calcium removal and thin filament deactivation. Thus, diastolic dysfunction might result from two factors: i) a loss of the sensitivity of relaxation to strain rate and ii) an attenuation in strain, restricting the strain rate. The molecular mechanism underlying strain-rate sensitivity remains unknown, but our preliminary studies indicate that myosin detachment kinetics are key. Strain-sensitive myosin detachment is a poorly characterized biophysical property, especially in intact cardiac tissues. Our preliminary data further demonstrates that in vivo hemodynamics can alter myocardial strain. The global hypothesis of this proposal is that myosin-detachment kinetics biophysically regulates Mechanical Control of Relaxation. The goals of this project are to confirm this mechanism and to identify molecular and hemodynamic factors that regulate Mechanical Control of Relaxation. Aim 1 will determine whether myosin detachment rate modifies the sensitivity of the relaxation rate to the strain rate. We hypothesize that both myosin isoforms and myosin activating drugs will modify the strain-sensitive detachment rate of myosin. Using myosin isoform altering treatments and myosin-specific activating drugs, we will evaluate Mechanical Control of Relaxation using intact cardiac trabeculae. Importantly, we will assess myosin head position using x-ray diffraction techniques. Aim 2 will determine the role of titin based stiffness on Mechanical Control of Relaxation. Our preliminary studies suggest that high titin compliance eliminates a length (preload)-dependent change in myosin detachment. We hypothesize that titin-mediated thick filament extensibility is a mediator of relaxation and will test this hypothesis in trabeculae expressing altered titin isoforms using the same techniques as in Aim 1. Aim 3 will determine how strain rate and/or the sensitivity of the relaxation rate to the strain rate is modified in vivo using i) the molecular modifications studied in Aims 1 and 2 and ii) a clinically relevant Fructose+High Salt model that replicates several markers of heart failure with preserved ejection fraction. The proposed methods uniquely consider how the myocardium moves (strains) throughout the cardiac cycle, an advance beyond standard methods (isolated myofibril, trabeculae) that are isometric. These studies will drive the discovery of novel targets to improve the treatment and diagnosis of impaired relaxation by isolating mechanisms underlying Mechanical Control of Relaxation.

NIH Research Projects · FY 2025 · 2020-12

PROJECT SUMMARY/ABSTRACT Children with movement disorders are a big burden to society. The burden of disease is very high because of the life-long consequences to the patient, caretakers, and social institutions. Currently there are no cures or preventative treatments for cerebral palsy (CP), as the mechanisms of disease remain poorly defined. Human mutations in key enzymatic pathways constitute genetic causes of childhood movement disorders. With the advent of transgenic rabbit models, a golden opportunity has arisen to study the pathogenetic mechanisms in brain leading to movement disorders, as rabbits are more likely to present with movement disorders mimicking that of humans. Rabbits are perinatal brain developers like humans. Mutations in enzymes of tetrahydrobiopterin pathway result in movement disorders. Tetrahydrobiopterin is an enzyme co-factor and its supplementation in congenital deficiency disorders ameliorates the movement disorder. Thus, there may be a critical role of tetrahydrobiopterin in the development of movement disorders, such as CP. We developed a knockout rabbit that introducing a specific mutation in one of the tetrahydrobiopterin synthesis enzymes, sepiapterin reductase. Following fetal hypoxia-ischemia, newborn rabbits present with hypertonia and difficulty with balance. Fetal rabbits showing low developmental tetrahydrobiopterin in discrete brain regions have a greater disposition to develop hypertonia. Magnetic resonance imaging (MRI) allows us to predict which fetuses will develop postnatal hypertonia. This advance allows the identification of early critical pathways causing hypertonia. Our objective is to elucidate molecular mechanisms of perinatal brain injury in human mutations causing childhood movement disorders, by decreasing tetrahydrobiopterin levels using a hetero- and homozygous knockout transgenic approach in the rabbit. The main question asked in this proposal is whether tetrahydrobiopterin in selective brain regions contributes to the development of motor disorders with a severity determined by an added prenatal insult such as hypoxia-ischemia or inflammation. Using genetic knockout of sepiapterin reductase, we can further lower the tetrahydrobiopterin levels in brain and investigate whether the resulting motor deficits are increased or that we need less degree of insult to achieve the same motor deficits. The first Aim determines whether an added fetal insult, hypoxia-ischemia or inflammation from lipopolysaccharide, enhances movement disorders in the sepiapterin het/homozygous reductase knockout rabbit. The second Aim will determine if neuronal or oligodendroglial injury explains the development of movement disorders in the knockout rabbit. We use innovative pre- and postnatal MRI biomarkers of hypertonia with tissue flow cytometry and high-performance liquid chromatography with electrochemical detection. By conducting a time-dependent, organ-specific and cell-specific pathogenetic study, we will obtain a comprehensive picture of the role of this cofactor in perinatal pathogenesis of movement disorders.

NIH Research Projects · FY 2024 · 2020-08

Abstract This proposal support for a core-based scientist with our Cancer Center Support Grant (CCSG) as the parent grant, seeks career stability for Dr. Kamiar Moin the Director of the Microscopy, Imaging and Cytometry Resources core (MICR) of the Karmanos Cancer Institute (KCI). MICR is the largest facility core of KCI and is funded, in part, by the CCSG (P30-CA022453, Dr. Gerold Bepler PI/Unit Director; Dr. Moin is a co-investigator). Dr. Moin established MICR in 1994 as the Confocal Imaging Core in the Cancer Center and provided cutting- edge expertise and state-of-the-art technology in fluorescent microscopy, confocal microscopy and related techniques. From the beginning with only a 200 ft2 space and one instrument, Dr. Moin has expanded and significantly upgraded the MICR a number of times culminating into the current premier multimodal imaging and flow cytometry service center with over 4000 ft2 space and 22 capital instruments. Dr. Moin’s mission through MICR is to support and enhance the peer reviewed funded research activities of our scientific community whose research requires advanced cytometry as well as cellular, tissue, and animal imaging and analysis. To fulfill this mission, Dr. Moin strives to consistently meet several objectives, which are to: 1) provide expertise in analytical methods development, technology development and validation, imaging and cytometry study design; 2) provide collaboration and consultation for grant proposals and publications; 3) provide and maintain state-of-the-art advanced instrumentation in flow cytometry, microscopy and imaging; 4) promote opportunities for intra- and inter-programmatic interaction among our scientific members; 5) minimize cost and effort for KCI investigators while increasing efficiency and 6) provide educational and training opportunities in microscopy, imaging and flow cytometry. Dr. Moin is a nationally and internationally recognized expert and leader in imaging and cytometry, evident by his service on 18 NIH study sections and numerous presentations and workshops, with over 30 years of experience and more than two decades of facility core management and administrative skills. His expertise in imaging and cytometry with a proven track record in technology and methods development is critical to the CCSG and the 25 NCI funded investigator-initiated research projects utilizing MICR. This application, if funded, will support 100% of his efforts and will offset some of the costs incurred by the individual NCI funded projects by reducing the chargeback rates. The R50 will provide career stability without dependence on individual grant and allows him to prioritize his effort on those projects that require methodology and technology development. The funds requested for travel will enable Dr. Moin to attend conferences in imaging and cytometry and/or core facility management meetings such as the Association of the Biomolecular Research Facilities (ABRF), to continue his education in imaging/cytometry and core management to be effective in his role to support the NCI funded projects.

NIH Research Projects · FY 2024 · 2020-08

Herpes  stromal  keratitis  (HSK)  is  a  chronic  inflammatory  condition  that  develops  in  response  to  a  recurrent  corneal  infection  with  herpes  simplex  virus-­1  (HSV-­1).  HSK  is  the  leading  cause  of  infection-­induced  corneal  blindness  in  the  United  States.  Clinical  manifestation  of  HSK  involves  the  development  of  opacity  and  neovascularization into the avascular cornea. Newly formed leaky blood vessels in the corneal stroma obscure  the visual axis, traffic the leukocytes (mostly neutrophils) into the inflamed cornea, and cause the corneal edema.  The  current  mainstay  of  HSK  treatment  requires  the  long-­term  use  of  oral  antiviral  drugs  and  the  topical  application  of  steroids.  The  prolonged  use  of  topical  steroids  causes  a  predisposition  to  herpetic  reactivation,  cataract  development,  and  increased  intraocular  pressure  (IOP),  which  may  cause  the  development  of  glaucoma. A better understanding of cellular and molecular events involved in the pathogenesis of HSK could  provide  novel  therapeutic  targets  to  reduce  the  severity  of  HSK.  The  focus  of  this  application  is  to  understand  the mechanisms by which Insulin-­like growth factor binding protein-­3 (IGFBP-­3) regulates the pathogenesis of  HSK. IGFBP-­3 exerts its effect through insulin-­like growth factor (IGF)-­independent and-­dependent mechanisms.  In  an  IGF-­independent  manner,  IGFBP-­3  is  known  to  induce  cellular  senescence.  The  cellular  senescence  is  reported to inhibit viral replication. The IGF-­dependent activity of IGFBP-­3 involves sequestration of IGF-­1 and  IGF-­2  molecules  and  limiting  their  bioavailability  to  IGF-­1R,  and  thereby  regulates  IGF-­1R  signaling.  Our  preliminary results showed an elevated expression of IGFBP-­3 in HSV-­1 infected corneas of B6 mice, whereas  a  significantly  reduced  amount  of  IGFBP-­3  protein  was  detected  in  the  circulation  of  infected  B6  mice  when  compared  to  uninfected  B6  mice.  The  infected  corneas  of  IGFBP-­3  knockout  (IGFBP-­3  KO)  mice  showed  an  increased  viral  load.  Besides,  increased  phosphorylation  of  IGF-­1R,  the  first  step  in  IGF-­1R  signaling,  was  determined  in  leukocytes  infiltrating  the  HSK  developing  corneas  of  IGFBP-­3  KO  than  B6  mice.  A  significant  increase  in  hemangiogenesis  and  opacity  was  measured  in  infected  corneas  of  IGFBP-­3  KO  than  B6  mice.  Together,  these  results  led  us  to  hypothesize  that  IGFBP-­3  enhances  viral  clearance,  reduces  angiogenesis,  and  decreases  the  survival  and  effector  function  of  myeloid  cells  in  HSK  developing  corneas.  Therefore,  enhancing the IGFBP-­3 protein level in HSV-­1 infected cornea should alleviate the severity of HSK. Three aims  are proposed to test our hypothesis. Aim I will test the hypothesis that hypoxia enhances IGFBP-­3 expression  in corneal epithelial cells, and an increased level of IGFBP-­3 induces senescence in epithelial cells, and cellular  senescence  promotes  HSV-­1  clearance  from  the  infected  cornea.  Aim  II  will  test  the  hypothesis  that  IGF-­1R  signaling  in  myeloid  and  vascular  endothelial  cells  control  the  severity  of  HSK.  Aim  III  will  test  the  hypothesis  that increasing IGFBP-­3 protein in HSV-­1 infected cornea alleviates the severity of HSK.

NIH Research Projects · FY 2024 · 2020-07

PROJECT SUMMARY Cachexia has a devastating impact on survival and quality of life of many cancer patients and remains an unmet medical need. Pancreatic cancer patients present with the highest incidence of cachexia (~90%), and approximately one-third of these patients lose more than 10% of their pre-illness weight, leading to general muscle weakness, impairment of normal activities, and eventually death through respiratory failure. A deeper understanding of the underlying mechanisms that lead to the complex metabolic defects of cachexia, coupled with effective treatment options, would improve management of muscle wasting in cancer patients. We have recently reported that ectopic expression of the transcription factor Twist1 in muscle progenitor cells is sufficient to cause severe muscle atrophy akin to muscle cachexia. Using several genetic mouse models of pancreatic ductal adenocarcinoma (PDAC), we detected high Twist1 expression in muscle undergoing cancer cachexia. Of particular importance, inactivating muscle Twist1, either genetically or pharmacological, was sufficient to reverse muscle cachexia and improve survival in several genetic mouse models of cancer cachexia, implicating Twist1 as a possible target for attenuating muscle cachexia in cancer patients. Quite serendipitously, we found that muscle Twist1 was highly crosslinked during cancer cachexia. We obtained strong evidence that this process was mediated by the crosslinking enzyme Transglutaminase 2 (TGM2). Treatment of cells with a specific TGM2 inhibitor completely suppressed Twist1-induced expression of MuRF1 and Atrogin1, two ubiquitin ligases that drive muscle protein degradation during muscle cachexia. Other preliminary data showed that expression of Twist1 in vivo promotes muscle TGM2 expression. More crucially, we detected a marked increase in both muscle Twist1 and TGM2 expression in cachectic cancer patients as compared to healthy individuals, attesting to the clinical relevance of our findings. Based on these intriguing findings, we hypothesize that TGM2 might function in partnership with Twist1 to orchestrate a feed-forward network that initiates and sustains muscle cachexia during cancer progression. We also hypothesize that developing combinatorial therapeutic strategies targeting both TGM2 and Twist1 could mitigate potential drug toxicity by lowering the dose needed for each medicine and combat the development of resistance. These overarching hypotheses will be tested in our research proposal. Specific Aim 1: Investigate the relationship between TGM2 and Twist1 during muscle cachexia Specific Aim 2: Explore the role of the TGM2-Twist1 axis in muscle cachexia using genetic approaches Specific Aim 3: Test the therapeutic value of targeting both TGM2 and Twist1 in muscle cachexia We believe that our innovative proposal to exploit this novel TGM2/Twist1 axis in muscle cachexia will culminate in a paradigm shift in our understanding and therapeutic treatment of this lethal wasting syndrome.

NIH Research Projects · FY 2025 · 2020-05

Project Summary NACHT, LRR and PYD domains-containing protein 3 (NLRP3) is a critical component of the innate immune system that forms the NLRP3 inflammasome, an intracellular molecular platform that drives caspase-1 activation and the secretion of biologically active IL-1β and IL-18. In addition to its protective role in innate immunity, aberrant activation of the NLRP3 inflammasome contributes to the pathogenesis of several inherited and acquired inflammatory disorders, such as Cryopyrin-associated autoinflammatory syndrome, gout, Crohn's disease, Alzheimer's disease, diabetes and atherosclerosis. Despite extensive investigation, the molecular mechanism leading to NLRP3 inflammasome activation remains elusive. Recently, the protein kinase Nek7 has been found to mediate NLRP3 inflammasome activation independently of its kinase activity. However, it is unknown how Nek7 is mechanistically linked to NLRP3 inflammasome activation. Our recent studies implicate a critical role for Nek7 phosphorylation in NLRP3 inflammasome activation. In this application we aim to elucidate the molecular mechanism of Nek7-mediated NLRP3 inflammasome activation and determine the role of a novel regulator in this pathway. Our results are expected to provide new mechanistic insights into NLRP3 inflammasome activation and might guide the development of novel therapeutic strategies for treating NLRP3-driven inflammatory diseases.

NIH Research Projects · FY 2024 · 2020-04

Gastrointestinal and cardiovascular health are intimately linked, yet the mechanism by which diet-derived lipid metabolites and the gut microbial flora impact efferent sympathetic nerve activity is largely unknown. Work from our laboratory and others’ provides increasing evidence that the enteric nervous system directly influences the sympathetic control of systemic blood pressure. The viscerosensory-sympathetic network is a functional neural circuit connecting afferent sensory fibers of the gut and efferent vasoconstrictor neurons at the level of the spinal cord. While this neural circuitry likely influences systemic blood pressure in able-bodied individuals, its role in the development of severe hypertensive crises in patients living with spinal cord injury (SCI) is irrefutable. Autonomic dysreflexia (AD) is often a clinical emergency in SCI individuals and is characterized by paroxysmal hypertension in response to otherwise innocuous visceral stimuli (e.g. fecal impaction). Despite its obvious significance, mechanisms involved in the regulation of viscerosensory-sympathetic reflexes (VSSRs) are poorly understood. Our preliminary studies indicate that C-fiber sensory neurons expressing transient receptor potential cation channel V1 (TRPV1) are involved in the afferent limb of the viscerosensory-sympathetic circuitry. Our proposal seeks to (Aim 1) provide a mechanistic understanding of the role of diet-derived lipid mediators in exaggerating the AD phenotype, (Aim 2) interrogate novel therapeutic strategies for attenuating sympathetic hyperreflexia following SCI, and (Aim 3) define the role of SCI-associated gut dysbiosis in contributing to the production of pathogenic diet-derived lipid mediators. Our central hypotheses identify new pathogenic factors (dietary fatty-acid content and SCI-associated dysbiosis) and a biochemical mechanism (diet-derived TRPV1 lipid ligands) that may be independent targets for therapeutic intervention. Uniquely, our rationally designed therapeutic strategies target the major underlying cause of AD (i.e. visceral C-fiber hypersensitivity) rather than the symptomatic outcome (i.e. acute hypertensive crisis) and thus constitute a major paradigm shift.

NIH Research Projects · FY 2026 · 2019-06

Summary Most biological events in the cell are mediated at some level by protein post-translational modifications. For example, aberrant protein phosphorylation catalyzed by kinase and phosphatase enzymes is linked to a wide variety of cancers. Similarly, the unregulated acetylation state of histone proteins, controlled by histone deacetylase (HDAC) proteins, can lead to epigenetic changes in transcription and ultimately disease. Key to characterizing both healthy and disease states is a detailed molecular understanding of the role played by protein post-translational modifications, such as phosphorylation and acetylation, on protein function and interactions. Importantly, enzymes regulating protein post-translational modifications, including kinase, phosphatase, and HDAC proteins, are targets of therapeutics. Yet, tools linking specific protein modifications to downstream biological activities are often limited or unavailable, which has stalled progress in disease characterization and drug development. The NIGMS-funded projects in the Pflum lab address the critical need to develop innovative chemical approaches to discover unanticipated roles of protein post-translational modifications and their modifying enzymes in cell biology. In our work with protein phosphorylation, we pioneered use of g-phosphoryl modified ATP analogs in kinase-catalyzed labeling reactions. Building on this prior work, we propose in the next 5 years to 1) develop a new suite of methods with unique abilities to probe kinase- and phosphatase- substrate pairs and multi-protein complexes in cells, and 2) apply our innovative tools to a variety of biological problems in collaboration with biologists. In our work with protein acetylation, we have demonstrated the power of using inactive mutants as traps to discover non-histone substrates of HDAC1 and HDAC6, which has revealed unexpected roles in cell biology. In the next 5 years, we will apply this powerful trapping strategy to additional HDAC protein isoforms, which will establish the role of HDAC proteins in activities beyond epigenetics and transcriptional regulation. In a new direction for the program, trapping will be expanded to demethylase enzymes, which regulate protein methylation. Given the critical role of kinase, phosphatase, demethylases, HDAC enzymes in disease and drug treatment, yet the inadequate tools available to study these enzymes in complex cellular systems, the enabling chemical strategies proposed in this application will strengthen biomedical research in cell biology and drug design.

NIH Research Projects · FY 2025 · 2019-03

Wayne State University (WSU)/ Karmanos Cancer Institute (KCI) has been an active institutional member of the cooperative group system since 1972, an NCI designated Comprehensive Cancer Center since 1978, and a parent institution Phase I (U01) since 1993. We have an active membership in the NCTN and have been an active LAPS since its inception in 2013 enrolling patients in network trials through the CTSU and using the CIRB for activation. We have enrolled over 5,500 patients onto NCTN clinical trials over the past forty years and over 250 patients have been enrolled onto interventional trials since 2014, meeting and exceeding accrual goals in a consistent manner. Since April 2014, we have opened 52 NCTN trials, including 8 Alliance, 13 ECOG-ACRIN, 17 NRG and 14 SWOG. All adult NCTN qualifying Phase II and III protocols have been submitted through the CIRB for activation since 2009. Over the years, our faculty members have played an important role in both the administrative and scientific functions of the NCTN. Since 2014, eight faculty members have held nineteen leadership positions in SWOG and ECOG-ACRIN as well as serving on NCI organ site Task Forces and Steering Committees. Since 2014, 13 faculty members have been authors or co-authors of 41 NCTN abstracts or manuscripts, and 7 faculty members have been PI or Co-PIs of 11 NCTN clinical trials. Our Cancer Center is a unique urban based center of research, patient care and education which is reflected in our recruitment of minorities (24%) and women (44%) onto intervention trials. Since our inception, the cancer programs of WSU/KCI have been organized as multidisciplinary disease programs built on the premise that multidisciplinary clinical research and care provides the best treatment option for patients with cancer. Accordingly, the translation of ideas into Network Group proposals and studies and the incorporation of NCI designated high-priority trials into the WSU/KCI treatment priorities have been easily facilitated. NCI funded trials have the highest priority for activation within our institution. Dr. Lawrence Flaherty, a SWOG member since 1988, the SWOG U-10 PI since 1996 and LAPS PI since 2013 will serve as the PI of this submission. He was the SWOG Melanoma Vice Chair from 1990 until 2011 and has been Chair of the SWOG Data Safety and Monitoring Committee since 2011. Anthony Shields, M.D., PhD. is the Project Director/Principal Investigator of the WSU/KCI LAPS serves on the NCI Colon Cancer Task Force, the ECOG-ACRIN Principal Investigator Committee, the Scientific Planning Committee, and the Nomination Committee. He is the co-chair of the Experimental Imaging Sciences Committee and the Biomarker Steering Committee.

NIH Research Projects · FY 2025 · 2018-09

Abstract Detection of moving objects is a retinal function which is crucial for an animal's survival. Multiple neurons and neural networks in the retina have been identified as critical players in this task, including starburst amacrine cells (SACs) and direction-selective ganglion cells (DSGCs), which sense direction of motion. Recent studies have revealed that several neural networks among bipolar and amacrine cells are involved in direction selectivity. However, the impact of environmental factors on motion sensitivity tuning of these neurons is not well understood. Background scenery affects the gain control and tuning of neurons for object motion detection; however, we have just begun to understand the sensitization and adaptation of those neurons. The long-term objective of the present project is to understand the cellular and molecular mechanisms in the retina for sensing direction of motion. We will conduct patch clamp recordings, two-photon calcium imaging, immunohistochemistry, computational simulation, and behavioral studies to examine the mechanisms underlying direction selectivity. We previously found that cholinergic feedback from SACs to bipolar cells contributes to SAC direction selectivity. We now have evidence that the cholinergic feedback is transferred for a long distance and tune SAC direction selectivity. Therefore, we hypothesize that an incoming object send a signal to bipolar cells through a cholinergic pathway to tune SAC direction selectivity, a form of predictive coding. We propose two Specific Aims to investigate long-distance cholinergic feedback. We will test this hypothesis by recording long-distance cholinergic feedback in bipolar cells (Aim 1), and we will examine the outcome of the long-distance cholinergic feedback in bipolar cell axon terminals, SAC dendrites, and DSGC activity (Aim 2). Visual prediction is an essential feature for motion detection, which would reduce neural signal delays and facilitate the animal reaction. Knowledge gained from the results of this project will shed light on the additional layer of motion detection and visual signal processing in the retina.

NIH Research Projects · FY 2025 · 2018-09

Project Summary Endurance exercise is a highly effective intervention for ensuring healthy metabolism and maintaining healthy function during aging, but is unavailable to patients with illnesses or injuries that restrict their movement. Here, we follow up on previous discoveries from the fruit fly model system showing that stimulation of octopamine secretion from the brain acts through receptors in muscle and fat to coordinate benefits of exercise in sedentary animals. Here, we propose to identify genetic factors that mediate increased neuronal branching in the exercising brain (Aim 1), elucidate the pathway regulating the response to octopamine in exercising muscle (Aim 2), and by extending these results into humans for the first time using virtual reality stimulation to produce some benefits of exercise in sedentary humans (Aim 3).

NIH Research Projects · FY 2026 · 2017-09

Project Summary Bacterial endophthalmitis is a vision-threatening complication of eye surgeries and ocular trauma. The vision loss in endophthalmitis occurs due to uncontrolled inflammation-mediated retinal tissue damage. The long-term goal of our research has been to study the pathobiology of endophthalmitis and identify potential therapeutic targets for treatment. Our recent work using transcriptomics and metabolomics has uncovered the importance of cellular metabolism in regulating the innate immune response during experimental Staphylococcus aureus (SA) endophthalmitis. Notably, we observed significant impairment in the antioxidant glutathione peroxidase 4 (GPX4) signaling, which plays a crucial role in reducing lipid peroxide accumulation and preventing ferroptosis cell death. Ferroptosis, a newly discovered form of cell death linked to iron overload, is regulated by GPX4. Surprisingly, the role of the GPX4/Ferroptosis axis in ocular infections has remained unexplored. Based on our findings, we hypothesize that reduced GPX4 levels, combined with elevated iron levels during endophthalmitis, contribute to ferroptotic cell death in the retina. In support, our preliminary data show, downregulation of GPX4, an increased labile iron pool, excessive lipid peroxidation, and induced expression of ACSL4 in SA-infected retina and cultured cells. Here, we will employ mouse genetic tools and pharmacological interventions to elucidate the mechanisms underlying impaired GPX4 signaling (Aim 1), investigate the role of ACSL4 as the final executor of ferroptosis (Aim 2), and test potential of nanoformulations to enhance GPX4 levels and reduce ferroptosis as a novel approach to treat bacterial endophthalmitis (Aim 3). The knowledge gained from this study into the regulation of ferroptosis during endophthalmitis and the development of therapeutic strategies could have a significant impact not only on ocular infections but also on other eye diseases involving ferroptosis. Ultimately, our work aims to contribute to the advancement of therapeutic interventions in the field, offering new hope for preserving vision and improving outcomes in patients affected by these conditions.

NIH Research Projects · FY 2026 · 2017-07

The Michigan SIREN Collaborative (MI-SIREN) is organized around a strong network of research universities and hospitals with long-term successful collaborations. MI-SIREN includes 2 previous NETT hubs (Wayne State University (WSU) and Henry Ford Health Systems). MI-SIREN encompasses a hub and 8 primary spokes situated within 7 sizeable health care systems. MI-SIREN is affiliated with five major research universities, Wayne State University, Michigan State University, University of Michigan, University of Virginia and Oakland University. MI-SIREN accounted for over 940,000 ED annual visits in 2019 and 2020. MI-SIREN incorporates eight designated ST elevation myocardial infarction (STEM) centers, seven level 1 trauma centers, four Children’s hospitals, three certified burn centers, and three level 1 pediatric trauma centers. MI-SIREN has the capacity to provide the diverse population of critical patients required for SIREN. MI-SIREN incorporates innovative enrollment and retention practices like a three-tiered enrollment, designated duties, and shared employees which reduces errors and increases enrollment. MI-SIREN has tight collaboration with EMS divisions in metropolitan Detroit, Ann Arbor, Grand Rapids, and Charlottesville, Virginia and has performed multiple Exception From Informed Consent (EFIC) studies. MI-SIREN is the third highest enroller in the current SIREN Network with exceptional quality metrics. MI-SIREN provides access to nearly the entire population of Detroit, MI, approximately 680,000 with 82% African American, and 49.8% living below the poverty level. MI-SIREN will build upon our exemplary subject recruitment by leveraging shared resources, making strategic investment into spokes, and expanding capacity. MI-SIREN will support, engage, and train the next generation of diverse clinical scientists. MI-SIREN will encourage faculty to enrich SIREN leadership and actively pursue grant proposals utilizing the SIREN network. MI-SIREN offers a pipeline for SIREN grant submissions through our expert faculty. MI-SIREN has a proven record of engaged high quality performance of clinical trials.

NIH Research Projects · FY 2025 · 2017-04

Pseudomonas aeruginosa (PA) keratitis is one of the most rapidly developing and destructive diseases of the cornea and a global cause of visual impairment and blindness. Emergence of antibiotic-resistant strains poses additional challenges for effective disease management. Development of alternative treatment is urgent. In this regard, microRNAs (miRNAs) are small, non-coding RNAs and important regulators of gene expression. miRNAs play critical roles in human diseases and are viable therapeutic targets. However, the roles of miRNAs in PA keratitis remain largely unexplored. Our long-term objectives are to uncover the molecular mechanisms of miRNAs in ocular infectious diseases, identify novel miRNA-based therapeutic targets and develop alternative treatment of these diseases. The proposed research will directly address this knowledge gap. It is built upon our recently published and strong preliminary data showing that application of anti-miRs targeting the miR-183/96/182 cluster (referred to as miR-183C from here on) and knockout of miR-183C in mice decreases corneal nerve density and neuropeptide production, while reducing the severity of PA keratitis; miR- 183C targets key genes regulating corneal sensory innervation, e.g., Nrp1, bacterium-induced sensory-neuron activation and neuropeptide production, e.g., Toll-Like Receptor (TLR)4, Formyl Protein Receptor (Fpr)1 and substance P (sP) precursor gene Tac1. These data lead us to the overarching hypothesis that, in addition to innate immunity, miR-183C modulates PA keratitis through its regulation of corneal sensory nerve function and neuroimmune interaction by targeting key genes involved in sensory innervation, PA-induced sensory-neuron activation and pro-inflammatory neuropeptide production. Three Aims are proposed in this application to test this hypothesis. In Aim 1, fluorescein amidites (FAM)-labeled anti-miR-183C will be applied to the cornea of wild-type (WT) mice to test the hypothesis that anti-miR-183C treatment upregulates Tac1, TLR4, Fpr1 and Nrp1 in corneal sensory nerves, resulting in increased pro-inflammatory neuropeptides (e.g., sP) and an early immune/inflammatory response (<24 hours post-infection) and an accelerated sensory-nerve reduction and decreased pro-inflammatory neuropeptides and immune/inflammatory response in a later stage during disease resolution. Aim 2 will test the hypothesis using a sensory neuron-specific miR-183C conditional knockout mouse model. Aim 3 will test the hypothesis that knockdown or knockout of miR-183C in vitro/ex vivo in both human and mouse sensory neurons parallels the in vivo data in that it will upregulate Tac1, TLR4 and Fpr1 to enhance PA-induced secretion of pro-inflammatory neuropeptides by sensory neurons, and increase Nrp1 expression to inhibit neurite growth. A genome-wide identification of miR-183C target genes in both human and mouse trigeminal ganglion sensory neurons will also be conducted by RNA seq. This study will provide novel biological insights into molecular bases of miR-183C's regulation of PA keratitis and other ocular infectious diseases. It will uncover mechanisms and reveal new targets for anti-miR therapy.

NIH Research Projects · FY 2026 · 2017-04

Project Summary Bacterial endophthalmitis is a vision-threatening complication commonly occurring post penetrating eye injuries and ocular surgeries. Despite aggressive antibiotics and surgical interventions, endophthalmitis often results in partial or complete vision loss. The long-term goal of our research has been to study the pathobiology of endophthalmitis and identify potential therapeutic targets for treatment. In our recent study (PMID: 34095879), using transcriptomics and untargeted metabolomics, we identified several key pathways related to energy metabolism being perturbed during Staphylococcus aureus (SA) endophthalmitis. Among these pathways, we found that bacterial infection rapidly depletes the nicotinamide adenine dinucleotide (NAD+) pool in the mouse retina. NAD+ is not only crucial for oxidation-reduction reactions in the mitochondria, but metabolites of the NAD+ pathway also serve as substrates for various enzymes (e.g., PARPs, sirtuins, and CD38) to maintain cellular homeostasis. Thus, dysregulation in NAD+ metabolism has emerged as a contributing factor in the pathogenesis of several diseases. However, its role has not been investigated in ocular infections. Here, we propose that NAD+ depletion causes bioenergetics collapse, leading to the activation of receptor-interacting protein kinase-3 (RIPK3) mediated retinal cell death. In support, our preliminary data show disruption of the NAD+ synthesis via salvage pathway, increased activity of CD38 NADase, and the activation of RIPK3/MLKL signaling in SA-infected retina and cultured cells. Using a combination of mouse genetic tools, gene therapy, and pharmacological interventions, we will determine mechanisms of NAD+ depletion and restoration of salvage pathway (Aim 1), elucidate the crosstalk between CD38 NADase activity and RIPK3 in regulating retinal cell death (Aim 2), and test the hypothesis whether supplementation of NAD+ precursors can be used as an adjunct therapy to treat bacterial endophthalmitis (Aim 3). Collectively, the mechanistic insights on NAD+ dysregulation and NAD+ supplementation treatment strategies developed in this proposal could have a major impact in the field, not only with regards to ocular infections but other systemic infectious diseases as well.

NIH Research Projects · FY 2026 · 2017-02

Project Summary/Abstract Despite progress made in early detection and treatment, African Americans continue to experience disproportionately higher cancer incidence rates, are first diagnosed with more advanced stage disease, and suffer higher mortality rates than other populations. The Detroit Research on Cancer Survivors (ROCS) study (U01CA199240) is the largest single cohort of African American cancer survivors aimed at understanding the multiplex causes of poorer outcomes in this population. Detroit ROCS has been collecting survey data and biospecimens with a goal of enrolling 5,000 population-based African Americans diagnosed with lung, breast, prostate, colorectal, and endometrial cancers and any early- onset cancer (diagnosed age 20-49 years) and supporting studies addressing determinants of cancer outcomes and quality of life. In this renewal application, we will continue to follow cohort survivors annually for up to 9 years to address the determinants of longer term outcomes (e.g., disease recurrence, second primary diagnoses, treatment related comorbidities and death) and quality of life. The broad research agenda will be developed with our community partners. We propose to: 1) conduct annual follow-up surveys on all living, enrolled participants for up to five additional years and collect additional biospecimens; 2) engage with members of the community to set new research priorities and to obtain input into the retention of participants and dissemination of research findings back to the community; 3) link Detroit ROCS patient data to other existing sources of health-related and exposure data to supplement patient-reported information; and 4) extend collaborations to facilitate use of the data and biospecimens by the broader research community. Detroit ROCS is providing substantial data and biospecimens to facilitate studies aimed at understanding and addressing determinants of poor outcomes in this population.

NIH Research Projects · FY 2025 · 2016-06

PROJECT SUMMARY Hydrocephalus, an imbalance between cerebrospinal fluid production and absorption, is diagnosed in more than 1 in 500 people in the United States. Approximately 80% of these patients will suffer long-term neurological deficits. Genetic diseases, meningitis, subarachnoid hemorrhage, stroke, traumatic brain injury, or tumors cause hydrocephalus. The common treatment for all hydrocephalus patients is CSF drainage by shunting. Despite all our efforts, shunts still have the highest failure rate of any neurological device. A shocking 85% of shunts fail after just ten years. Failed shunts are plagued with astrocytes and macrophages, but we still do not understand the process by which these cells are pulled in, migrate, and grow. In our first aim, we identify what patient conditions contribute to tissue contact and what variables trigger tissue pull in into shunt catheter holes. We clearly define physical variables that create instances of tissue pull in using computational fluid dynamics and a benchtop model (“Brain on a Bench”). We continue the use of this system in Aims 2 and 3. In this way, we investigate what single or repetitive events cause shunt catheter contact and tissue pull in with the ventricular wall, parenchyma, or choroid plexus. In our second aim, we determine if cell growth is a necessary component to shunt obstruction after contact with a tissue source occurs. We examine the growth, proliferation, and activation state of the cells following single or repetitive contact with ventricular wall, parenchyma, and choroid plexus just as we did in Aim 1. In our final aim, we use our heightened awareness of tissue pull in and tissue growth to understand how changes to shunt design can influence shunt obstruction. We prioritize the clinical conditions shown to exacerbate tissue contact and test under physical variables that show direct pull in and growth of ventricular wall, parenchyma, and choroid plexus. In summary: our patient data informs us of the patient conditions that correlate to contact of ventricular wall, parenchyma, and choroid plexus. Benchtop and computational fluid dynamics models prioritize these environmental conditions while systematically testing what variables cause tissue pull in and growth. Strategies to prevent obstruction by inhibition of pull in and growth are tailored for ideal performance under the conditions set by our patient and benchtop data. Altogether, these data improve our mechanistic understanding of shunt obstruction necessary to and narrow our area of focus for improved treatment of hydrocephalus.

NIH Research Projects · FY 2025 · 2015-02

Project Summary/Abstract For the millions of epilepsy patients with drug-resistant seizures, surgical resection of epileptogenic brain tissue is often the only remaining therapeutic option. Especially in young patients who do not obtain seizure control or suffer from unacceptable side effects from medications, there are further concerns about the effect of seizures on development: even brief but repetitive seizures cause cognitive regression and detrimental psychosocial effects. This motivates a particular urgency to investigate a more structured, quantitative, and non-invasive tool, which is capable of informing families and providers to decide timely surgery by accurately providing the probabilities of both favorable and unfavorable postoperative outcomes using data from preoperative imaging analysis at the whole-brain level. The overall goal of this project is to develop a novel tool of benefit-risk analysis for the presurgical evaluation of pediatric drug-resistant focal epilepsy. Toward this goal, we will validate a state- of-the-art deep learning-based diffusion MRI technique to provide the resection margin (i.e., the distance between epileptogenic area and eloquent area) resulting in maximized benefits (i.e., seizure freedom and long- term neurocognitive improvement) and minimized risk (i.e., deficits in eloquent functions including motor/language/hearing/vision). With NIH support, we have established diffusion-weighted imaging maximum a posteriori probability (DWI-MAP) analysis with Kalman filter, which can provide individual patients with the optimal resection margin, yielding successful avoidance of motor/language/visual deficits in 93%/91%/90% of patients with ≥75% of patients benefiting from seizure freedom. Recently, we have also found that deep convolutional neural network (DCNN) can provide an excellent accuracy (94-100%) to classify true positive tracts of eloquent brain areas, suggesting that DCNN-based tract classification may outperform the DWI-MAP in detecting diverse function-specific white matter pathways. Aim 1 of this project will investigate if a combination of DCNN-based tract classification with Kalman filter even better predicts the resection margin, resulting in seizure freedom and avoidance of functional deficits at a large cohort. Aim 2 will investigate if an advanced DWI approach integrating DCNN and DWI connectome helps decide timely surgery by providing 1) preoperative imaging markers underlying high likelihood of postoperative neurocognitive improvements and 2) mechanistic insight in structural brain reorganization associated with postoperative verbal IQ improvement. The results of this project are expected to ultimately improve clinical management of pediatric epilepsy by translating deep learning- based diffusion MRI technique to optimize the surgical margin, predict the postoperative neurocognitive outcome, and determine specific mechanism of postoperative brain reorganization, which will be validated for optimizing clinical benefit-risk analysis before surgical intervention.

NIH Research Projects · FY 2026 · 2014-04

PROJECT SUMMARY The goal of this resubmitted, competitive renewal R01 application is to execute an unprecedented, com- prehensive, parallel and rigorous examination of the processing of each polyglutamine (polyQ) disease protein through a novel, isogenic series of transgenic animals and approaches that span Drosophila ge- netics, physiology, mass spectrometry, mammalian cell biology and biochemistry. The polyQ family of proteins is linked to nine incurable neurodegenerative maladies: Spinocerebellar Ataxias (SCAs) 1, 2, 3, 6, 7 and 17, Huntington's disease, Dentatorubral-pallidoluysian atrophy and Kennedy's disease. While previous research yielded impactful insights into individual polyQ diseases, we lack a “birds-eye view” of the disease collective, which includes a concurrent analysis of the cellular processes key to the initiation and progression common to each polyQ disorder. Here, we propose to uncover the role of shared and distinct pathways in polyQ protein quality control. By the end of this proposed work, the field will have a comparative and mechanistic blueprint on how each polyQ protein is controlled and degraded in vivo. What we propose constitutes a rational and natural progression of the work that we conducted in prior cycles of this R01 award (04/2014-02/2023; currently in NCE). Based on our extensive work, we propose the hypothesis that polyQ diseases fall within distinct sub-categories of protein handling and toxicity, providing both a central- ized understanding of polyQ disease biology as well as establishing shared points of neuroprotection among these incurable disorders. We recently generated an isogenic series of transgenic flies to model the family of polyQ diseases. Each line contains the full-length human disease protein. Transgenes are integrated into a `safe harbor' site in the fly genome, are in the same orientation and consist of a single inserted copy. Through targeted genetic screens and hypothesis-based experimental design using this innovative series, we found overlapping components of protein quality control and related factors that serve to regulate several polyQ disease proteins; we also ob- served distinct regulatory processes that selectively affect some polyQ proteins, but not others. Now, we seek to expand on our observations to decipher the underlying mechanisms across the entire spec- trum of polyQ diseases by targeting key processes as well as focusing on individual cellular components. To bring additional relevance and physiological significance to our studies in Drosophila, we will complement our investigations with iNeuronal cultures differentiated into relevant cell populations. Assessments including fly morphology, mobility, longevity, genetics, mass spectrometry, cell biology and biochemistry will provide action- able information on the role of key cellular components involved in the degradation of polyQ proteins and their toxicity in an intact, multicellular organism and in the mammalian cell environment.

NIH Research Projects · FY 2025 · 2014-01

The cytosolic sulfotransferase (SULT) conjugating enzymes have the dual ability to metabolize endogenous compounds and xenobiotics, with consequences that include enhanced drug elimination, prodrug activation, hormone inactivation, and pro-carcinogen bioactivation. Unlike most other classes of xenobiotic-metabolizing enzymes, several SULTs are prominently expressed during prenatal life, implying that these enzymes perform important physiological functions in the developing human. Also, although the maternal liver and placenta protect the fetus against xenobiotic exposures, many xenobiotics can cross the placental barrier, making the SULTs especially important determinants of the impact of xenobiotic exposures on developmental processes. Our research group has shed new light on the hepatic expression patterns of the SULTs during human development. For example, we were the first to show that human estrogen sulfotransferase (SULT1E1), a major estrogen-inactivating enzyme, is robustly expressed in liver during gestation and substantially down- regulated after birth. However, the mechanisms that control the temporal expression of SULT1E1 and other prenatally-expressed SULTs, such as SULT1C2, are unknown. Also, the substrate specificities and enzymatic mechanisms of some SULTs are not adequately defined. In the proposed project, we will determine the mechanisms that control SULT1C2 and 1E1 expression during human liver development and will characterize in detail the enzymology of SULT1C2, one of the least studied of the SULTs, in order to understand its function in the developing human. We hypothesize that expression of the SULT1C2 and 1E1 genes is first upregulated and subsequently downregulated during human hepatocyte differentiation through the concerted action of a network of liver-enriched transcription factors, additional differentiation-associated transcription factors, and coregulators. We further hypothesize that the major substrates of SULT1C2 include endogenous molecules that are abundant during prenatal life as well as multiple classes of xenobiotics, and that substrate selectivity and catalytic activity are markedly influenced by structural rearrangements that are induced by binding of the SULT co-factor 3'-phosphoadenosine-5'-phosphosulfate. The specific aims of this project are to: (1) define the region(s) of the SULT1C2 and 1E1 genes that control their transcription in models of human hepatocyte differentiation; (2) identify the transcription factors and coregulators that control SULT1C2 and 1E1 transcription in models of human hepatocyte differentiation and in human liver specimens; and (3) characterize the structure-function activity of human SULT1C2. This project will increase our fundamental knowledge about the mechanisms that control endogenous and foreign chemical metabolism during human development, uncover new information about the function of a major SULT that is expressed during prenatal life, and provide new insight into the types of environmental exposures that could dysregulate SULT expression and function during this most vulnerable period of life.

NIH Research Projects · FY 2025 · 2012-04

Enter the text here that is the new abstract information for your application. All high school applicants seeking admission to Discovery to Cure High School Internship Program, regardless of race, ethnicity, or economic status, are given equal consideration for selection and participation.

NIH Research Projects · FY 2026 · 2011-01

Project Summary: Hypertriglyceridemia, a condition in which blood triglyceride (TG) levels are elevated, is a major risk factor of metabolic and cardiovascular diseases, such as type-2 diabetes, atherosclerosis, and non- alcoholic fatty liver disease. Clearance of plasma TG is primarily mediated by lipoprotein lipase (LPL). LPL, expressed by the parenchymal cells of lipolytic tissues, is transported to capillary lumen by the endothelial cell transporter GPIHBP1, where it hydrolyzes plasma TG for local uptake into peripheral tissues. Although significant progress has been made, the fine-tune regulation of LPL activity as well as TG lipolysis and partitioning into peripheral tissues remain to be further elucidated. In the last funding cycle, we revealed that the endoplasmic reticulum (ER)-tethered, liver-enriched transcriptional factor CREBH functions as a diurnal metabolic regulator that integrates circadian regulation to energy homeostasis. Recently, we discovered that the C-terminal fragment of CREBH (CREBH-C), produced through Regulated Intramembrane Proteolysis (RIP), is secreted from the liver into circulation as a “hepatokine” upon energy demands. Secreted CREBH-C interacts with angiopoietin-like 3 (ANGPTL3) and ANGPTL8 to prevent the inhibitory interactions between ANGPTL3/8 and LPL, thus promoting LPL activity and TG partitioning into peripheral tissues. Circulatory CREBH-C promotes TG clearance and partitioning and mitigates hypertriglyceridemia caused by over-nutrition. These lines of evidence prompted us to hypothesize that ER membrane-tethered CREBH is processed by RIP to produce a novel hepatokine, CREBH-C, which interacts with ANGPTLs to regulate intravascular LPL activity, TG partitioning into peripheral tissues, and whole-body metabolism. CREBH-C intervention may increase metabolic flexibility and thus mitigate hypertriglyceridemia and the associated metabolic disorders. In this application, we will utilize molecular and cellular approaches, genetic animal models, as well as innovative LPL-monitoring and lipid-tracing approaches to define a novel hepatokine, CREBH-C, and its regulatory roles in LPL activity and TG homeostasis: Aim 1, to define the mechanistic pathway by which the ER membrane-tethered CREBH is processed to produce a secreted form of CREBH; Aim 2, to delineate the regulation and mechanistic basis by which CREBH-C interacts with ANGPTL3/8 to regulate LPL activity; Aim 3, to determine the functional significance of CREBH-C in regulating TG partitioning and whole- body metabolism and in mitigating hypertriglyceridemia and the associated metabolic phenotypes. Within the funding period, we anticipate defining a new paradigm that a stress-induced protein fragment, derived from the ER membrane protein CREBH, can function as a potent hepatokine to regulate lipid homeostasis and whole-body metabolism. Revealing this unprecedented regulatory pathway for CREBH and its derived hepatokine will have important implications in therapeutic interventions toward the control of hypertriglyceridemia and the associated metabolic and cardiovascular disorders.

NIH Research Projects · FY 2025 · 2009-06

Project Summary/Abstract Disruption of cellular neutral lipid metabolism promotes the progression of obesity, diabetes, fatty liver disease, and cancer. The long-term scientific goal of the project is to understand the molecular mechanisms that control lipid storage and mobilization in order to identify novel points for therapeutic intervention. ABHD5 regulates cellular lipid metabolism, including PNPLA2/ATGL, the rate-limiting triglyceride lipase in key metabolic tissues. Nonetheless, the mechanisms by which ABHD5, a protein lacking enzymatic activity, activates PNPLA2 (and other PNPLAs) remains an important mystery. We hypothesize that the remodeling of biological membranes is a general mechanism by which ABHD5 regulates enzyme access to membrane-delimited neutral lipid substrates. Mechanistically, we hypothesize that ligand binding stabilizes ABHD5 molecular and macromolecular conformations that target and alter membrane biophysical properties (tension and curvature) to allow the lipase access to specific substrates sequestered within lipid droplets (LDs). We will test this hypothesis using novel chemical probes of ABHD5 and informative genetic mutants in live adipocytes (Aim 1). We will directly assess the impact ABHD5 on the biophysical properties of membranes in model LD systems using an array of high resolution and high throughput approaches (Aim 2). These Aims are designed to be highly complementary and to provide strong cross- validation between experimental platforms. In addition, we present data demonstrating that ABHD5 is targeted to specific subcellular sites where LDs form upon fatty acid supplementation. Furthermore, the interaction of ABHD5 with PLIN5, driven by the ABHD5 ligand oleoyl-CoA, facilitates LD formation. Aim 3 will dissect the biochemical pathways promoted by ABHD5/PLIN5 complexes and, in concert with Aim 2, evaluate the impact of this interaction on the biophysical properties of model membranes. ABHD5 is emerging as a compelling therapeutic target for metabolic diseases and cancer. The results of this project will provide new insights into specific mechanisms by which ABHD5 regulates fatty acid flux at the cytosol/LD interface.

NIH Research Projects · FY 2026 · 2009-03

We will determine the utility of a novel brain mapping technique for epilepsy presurgical evaluation, referred to as 'six-dimensional (6D) dynamic tractography'. This innovative program animates the rapid neural propagations along MRI-defined, 3D white matter tracts that connect regions supporting cognitive functions. Specifically, it will use event-related high gamma activity to localize the regions supporting specific linguistic functions and compute the velocity and strength of neural propagations based on the latency and amplitude of early neural responses to single-pulse electrical stimulation. We expect that considering both the negative effect of damaged white matter tracts and the positive effect of seizure control will help optimize the model's performance in predicting postoperative language outcomes; this will be accomplished by incorporating the 6D dynamic tractography and objective epilepsy biomarkers, including spontaneous high-frequency oscillations (HFOs) coupled to slow-waves, into our predictive model. By also identifying and considering the physiological high gamma augmentation strictly time-locked to stimuli and behaviors, our innovative intracranial EEG analysis will better distinguish the randomly- occurring pathologic HFOs. Another significant advancement provided by our model is its independence of conventional electrical stimulation mapping, which can acutely elicit seizures and fail to satisfactorily localize language areas in certain patient subsets. Additionally, this project will use 6D dynamic tractography to provide an explicit neurobiological model of language network dynamics, allowing us to tease apart the specific pathways originating from temporal lobe cortices that support the lexical retrieval of auditory or visual domains. Our prior project indicated that the arcuate fasciculus fibers support the direct transfer of lexical representations of auditory sentences. We will now determine whether the lexical representations of visual objects are likewise transferred via the arcuate fasciculus or others, including the fusiform-parietal fasciculus. To accomplish these goals, this project will prospectively recruit a new cohort of 80 epilepsy patients - age range: 0.5 to 21 years - undergoing extraoperative intracranial EEG recording and subsequent resective surgery. Finally, we will determine if the human brain creates and strengthens language-related functional parcellations throughout development. It has been suggested that the adult brain efficiently activates the posterior superior-temporal gyrus (STG) only during sound onset to decode the boundary between sounds. In contrast, the anterior STG shows sustained activation during an auditory stimulus to encode the phonetic features. We will determine if such a functional parcellation is more evident in older individuals, whose brains are more developed. While providing hypotheses focusing on specific brain regions, we will perform all of the proposed analyses at the whole-brain level. We will make all data and codes publicly available to facilitate external validation and implementation.