Virginia Commonwealth University

NIH Research Projects · FY 2025 · 2020-03

This first renewal of our T32 program will train pre- and post-doctoral scientists in multi-disciplinary translational cardiovascular research to improve diagnosis, treatment, and prevention of cardiovascular disease (CVD). CVD burden has been rising for decades in most countries and the age-standardized rate of CVD has also risen in locations where it had been previously declining (including many regions in the United States). Concurrently, the CVD workforce in the United States has been shrinking—including MD and PhD investigators who are trained in multidisciplinary CVD research and how to pursue solutions that would reduce the national and global CVD burden. The goals of this T32 training program are thus to attract and train a cohort of outstanding academic scientists in multidisciplinary translational CV research and build a robust training infrastructure to increase the number of scientists trained to conduct research to advance the treatment and prevention of CVD. Our 5-year proposal will enroll 1 MD, 1 PhD and 1 predoctoral trainee per year, each eligible for 3 years of training in CV science. The program builds on existing research strengths at Virginia Commonwealth University (VCU) including basic, clinical, and translational CV science using cellular, small animal, and single- and multi-center population cohort and clinical trials; and multiple educational programs supporting students and trainees in STEM fields as they pursue graduate degrees. Key features include: 1) multidisciplinary mentor teams matched to each trainee’s needs; 2) access to multiple phenotypic and biologic materials from major NIH-funded basic science, prospective cohort, or clinical trials at VCU via the supporting program faculty; 3) coursework from School of Medicine and other graduate-level programs to supplement trainee knowledge in CV research; and 4) institutional seminar programs that enhance interaction among individuals from multiple disciplines. New in this renewal are: a) adding predoctoral slots to support VCU graduate students interested in CV science; b) training in artificial intelligence methods, c) implementing a multi-principal investigator structure to broaden the expertise of the T32 leaders, d) preparing early-stage investigators to serve on mentoring teams and as future program leaders, and e) engaging trainees with community advisory boards to deepen their understanding of the bidirectional nature of translational research. The mentors in this training program include 25 established and 8 early-stage faculty from 14 departments. Each faculty member has extramural funding; strong institutional support in the form of financial resources, facilities, and equipment; and the ability to support trainees in key professional development activities, including presentations and grant/manuscript writing. Our first cycle enrolled its full complement of 8 trainees in CV science. All 5 graduates remain in academic medicine; they averaged 3.8 first-author publications, and 4 submitted proposals for peer-reviewed funding.

NIH Research Projects · FY 2025 · 2019-09

Project Summary The United States is currently in an opioid crisis, and NIDA is committed to research on the mechanisms and treatment of opioid use disorder. Current Food and Drug Administration-approved pharmacotherapies for opioid use disorder include the MOR agonist methadone, the MOR partial agonist buprenorphine, and the MOR antagonist naltrexone. However, the clinical utility of all three compounds is limited for various reasons. Therefore, it is imperative to develop novel and effective drug candidates with enhanced therapeutic effects and reduced undesirable effects. Recently, we have identified several highly selective and potent MOR modulators as novel leads for opioid use disorder treatment. They all showed more promising pharmacological profiles compared to other known drugs in this category. The current proposal will focus on further development of these leads for preclinical IND-enabling studies, and dynamic drug discovery and development pipeline construct. Four integrated specific aims will be pursued in this project in two phases. In the UG3 phase, we will 1) further Validate therapeutic profiles of the current leads with self-administration and PK studies, and 2) expand the small molecule library to build a dynamic drug discovery and development pipeline. In the UH3 phase, we will 1) conduct preclinical IND-enabling studies on the lead(s) identified from UG3 phase, and 2) compare in vivo pharmacokinetics and pharmacodynamics profiles of the new hits from UG3 phase with current leads to define our next generation of lead compound(s).

NIH Research Projects · FY 2024 · 2019-09

Colorectal cancer (CRC) is among the most common and deadly forms of cancer. In South Carolina, our group has documented racial CRC disparities that exceed national rates. Most colon tumors arise from adenomas (adenomatous polyps) that are detected via a screening colonoscopy. Gastrointestinal (GI) inflammation and aberrant DNA methylation are key processes driving adenoma formation and CRC risk. Sleep loss and circadian rhythm disruption can induce inflammation, alter DNA methylation, and increase CRC risk. African- Americans (AAs) differ from European-Americans (EAs) in their endogenous circadian timing, and they are more likely than EAs to have poor sleep and excessive stress (allostatic overload or ‘weathering’). This case- control study will test the hypothesis that disruption of circadian processes and sleep is associated with inflammation and adenoma risk among AA and EA patients receiving a screening colonoscopy. Molecular timekeeping is controlled by ‘clock genes’ that regulate circadian gene expression via epigenetic mechanisms. Clock genes can modulate inflammation (e.g., TNFα, IL-6 expression), and they act as tumor suppressors (e.g., the ‘Period’ or PER genes). Our research suggests that genetic variation or aberrant methylation in PER genes is associated with increased adenoma risk, and that sleep disorders can increase CRC risk. Melatonin is a clock-regulated hormone that suppresses GI inflammation and inhibits colon tumor growth by binding to its cellular receptors (MT-1, RORα). This study will characterize biobehavioral circadian disruption indicators (sleep disturbances, social jet lag, fatigue, stress), along with key molecular correlates (PER3 genotype and methylation of: clock genes [PER1, PER2, PER3]; clock-controlled genes [MT-1, RORα, TNFα, IL-6]; and global DNA methylation [LINE-1]) to determine their role in inflammation and adenoma risk. A biobehavioral framework will address the following Specific Aims: 1) Conduct a case-control study among patients undergoing a screening colonoscopy to determine whether circadian disruption indicators (DNA methylation, biobehavioral, genetic) are associated with adenoma case status relative to controls, and if the relationship is modified by race (N=1,000; 400 cases, 600 controls); 2) Determine if circadian disruption indicators are associated with inflammation in normal GI tissue (TNFα, IL-6 mRNA expression); 3) Determine whether behavioral and molecular circadian disruption indicators are related; 4) Among adenoma cases, determine if methylation of candidate circadian genes in adenomas differs from normal GI tissue. Our team has a strong track record of providing high quality colonoscopy services and in engaging AA and EA communities in research. Prospective data collection (relative to colonoscopy) and the use of valid, quantitative biobehavioral and molecular measures will limit the potential introduction of bias. This study will rigorously examine circadian-based behavioral and molecular risk factors as they relate to GI inflammation and colorectal adenoma risk. Circadian-based risk factors may serve as novel, modifiable targets for CRC prevention.

NIH Research Projects · FY 2025 · 2019-08

Title and the Abstract of the Parent Grant Title: REGULATION OF CERAMIDE SYNTHASE BY PROTEIN-PROTEIN INTERACTION Abstract: Ceramides form the backbone of all sphingolipids, and ceramide synthases (CerS) are critical enzymes for de novo production of ceramides. In spite of the key role of CerS in ceramide generation, there is a serious deficiency in understanding how these enzymes are regulated. The long-term goal of this project is to uncover and understand the fundamental molecular mechanisms of how CerS enzymes are regulated. Using a proteomics approach, we discovered that the small heat shock protein Hsp27 interacts specifically with CerS1. Based on our preliminary data we generated the novel hypothesis that Hsp27 is a negative regulator of CerS1 activity via direct interaction that can be modulated by p38-MK2 MAPK mediated phosphorylation of Hsp27, and that down-regulation of Hsp27 induces CerS1/C18:0-ceramide mediated cellular responses. To test this hypothesis, we propose the following Specific Aims: Aim 1: Define the biochemical significance of Hsp27 mediated CerS1 regulation in cells with respect to sphingolipid metabolism and signal transduction. Aim 2: Define the biological significance of Hsp27 mediated CerS1 regulation. Aim 3: Determine the mechanism of Hsp27- CerS1 protein-protein interaction. Overall, these studies will establish Hsp27 as an endogenous modulator of CerS1 and uncover a novel mechanism of how Hsp27 regulates CerS1 and CerS1/C18:0-ceramide governed mitophagy and cancer cell death. The knowledge generated from this study will help design mechanism-based novel therapies against cancer and other pathologies in which C18:0-ceramide is the key mediator by identifying new methods to modulate CerS1 activity.

NIH Research Projects · FY 2024 · 2019-07

Biomaterials are clinically used to replace lost or damaged tissue, but the surgical implantation procedure initiates an inflammatory response, which is orchestrated by macrophages. The long-term goal is to understand the signaling pathways used by macrophages to recognize biomaterial features and the resulting inflammatory processes that lead to tissue healing and regeneration. The objective of this proposal is to determine the contribution of cell-biomaterial interactions and danger-associated molecular patterns (DAMPs) in the regulation of Wnt ligands, and to elucidate the effect of macrophage-secreted Wnt ligands on T cell activation and stem cell recruitment and differentiation. The central hypothesis is that macrophages interact with biomaterials and DAMPs, triggering Wnt release that regulates bone healing by modulating T cell polarization and MSC proliferation. Our rationale is that macrophage activation is dependent on the physicochemical properties of biomaterials and the local environment. Macrophages respond to biomaterials by secreting inflammatory molecules, including Wnt ligands. Ablating Wnt ligand secretion in macrophages decreases their activation and disrupts the inflammatory response and bone-biomaterial integration. By identifying key signaling pathways that trigger Wnt ligand secretion, we can identify biomaterial surface modifications and signaling pathways that can be targeted to modulate and ameliorate the inflammatory process after biomaterial implantation to improve clinical outcomes. The central hypothesis will be tested in three aims: 1) Elucidate the role of integrin signaling in triggering Wnt secretion by macrophages in response to biomaterial physicochemical cues.; 2) Establish the effect of DAMPs in altering macrophage-secreted Wnt ligands; 3) Determine the effect of macrophage-secreted Wnt ligands on T cell polarization and MSC proliferation and differentiation after biomaterial implantation. We will pursue these aims using a combination of in vitro and in vivo studies with conditional transgenic knockouts in macrophages, pharmacological inhibitors, and macrophage adoptive transfer and CRISPR-mediated transcriptional activation to the activation of endogenous Wnt3a and Wnt5a expression. The study of Wnt signaling on macrophage behavior and as an orchestrator of the inflammatory response after biomaterial implantation is innovative and has yet to be studied. The proposed work is significant because it will determine the role of Wnt proteins in macrophage activation and will provide evidence of the importance of Wnt signaling in the inflammatory milieu that can be translated into other areas like chronic inflammatory diseases and cancer. The near-term expected outcome of this work is the understanding of Wnt signaling in macrophage activation and its contribution to the inflammatory and healing process in response to biomaterial surface characteristics. Results from this proposal will have an immediate positive impact in establishing the role of Wnt signaling in macrophage activation and inflammatory response to implanted biomaterials, providing novel targets for the modulation of this activation and inflammatory response.

NIH Research Projects · FY 2025 · 2019-05

Project Summary The current renewal proposal seeks to expand upon our successful initial award to clarify the mechanisms underlying observed associations between alcohol use disorder (AUD) and suicidal behaviors (SB), including non-fatal suicide attempts and suicide death. The research team has an extensive history of productive collaborations, including in the realm of psychiatric and substance use disorder research. We have access to longitudinal Swedish national registries including medical, criminal, census, family, and socioeconomic data for nearly 11 million individuals; these resources will be linked to create detailed datasets encompassing a wide range of risk factors at individual, familial, and environmental levels. We will utilize these resources to extend our prior research through the pursuit of four specific aims. In the first aim we will evaluate how AUD and post- traumatic stress disorder, or trauma exposure, relate via mediating or moderating pathways to risk of SB. We will apply well-established methods, including those that facilitate causal inference. Second, we will directly compare and contrast pathways to SB via AUD versus major depression (MD). AUD and MD constitute two primary correlates/risk factors for SB, but much remains unknown about distinctions and commonalities between these associations. The current proposal will focus primarily on the role of social dysfunction, with the goal of identifying factors that may improve risk assessment. Third, we will consider how AUD relates to two common medical conditions, cardiovascular disease and dementia, with respect to SB risk. Both conditions are themselves associated with increased SB risk but whether they mediate and/or exacerbate the impact of AUD is not known. Finally, we will leverage our expertise in genetic epidemiology by pursuing analyses that will clarify how aggregate genetic liability to AUD or SB, versus AUD and SB, is differentially related to psychopathology and other correlates of risk. Critically, Sweden and the US have comparable rates of suicidal behavior and share many characteristics, including an ethnically and socioeconomically diverse population; however, the US lacks registry resources comparable to those available in Sweden. We expect that the statistical power of these registries, in conjunction with the research team’s extensive expertise in psychiatric and substance abuse research, social and genetic epidemiology, and causal modeling, will yield substantive findings on the relationship between AUD and SB, with important implications for improving our efforts at SB prevention and intervention.

NIH Research Projects · FY 2025 · 2018-09

The goal of the Guided Research Experiences & Applied Training (GREAT) in Alcohol Studies program is to provide undergraduates with innovative, intensive summer research experiences, in the study of alcohol and related behavioral health outcomes, in order to create a pipeline to strengthen the biomedical and behavioral research workforce. Since 2019, the program has funded research experiences for 46 undergraduates with a majority of fellows continuing to another research experience. The program also boasts high STEM graduation rates and ~40% enrollment in graduate school. In the next funding period, GREAT in Alcohol Studies will bring together undergraduates from Virginia Commonwealth University and Rutgers University to: (1) offer an innovative, 8 week summer research experience for 10 program fellows, consisting of a combination of structured training (Week 1) and individual mentorship (Weeks 2-8) under faculty with expertise in substance use and behavioral health, designed to provide young researchers with foundational research skills, experiential learning, and responsible conduct of research training; (2) provide professional and career development opportunities for fellows, to facilitate student success in research and to prepare students for behavioral research careers; (3) offer fellows a comprehensive mentoring model including a mentor at each project site and “near peer” mentor from our alumni pool; and (4) disseminate program findings and student research through both traditional (e.g., scientific posters) and innovative (e.g., infographics) means, to train the next generation of researchers in the dissemination and translation of research. Professional and career development, as well as research internships, will extend beyond the summer program, affording support throughout the remainder of the fellow's academic career. Program success will be evaluated across recruitment, student program completion, and fellows' continued engagement in research and entrance into research-related careers. GREAT offers fellows exciting benefits including an expansion of alcohol-related research training within two R1 universities, cross-fostering of ideas and exchange of information between students at both sites, and expansion of student networks through additional mentorship opportunities.

NIH Research Projects · FY 2025 · 2018-08

Severe alcohol-associated hepatitis (sAH) has high short-term mortality, yet it currently has no FDA-approved therapy. Although return to drinking impacts quality of life and mortality in these patients, available pharmacological treatments and behavioral therapies have not been widely utilized in the care of this patient population. An optimal approach would involve the care integration of both alcohol-associated liver disease (ALD) and alcohol use disorder (AUD). Our combined team of experts in AUD and ALD seeks to overcome the perceived stigma of alcohol misuse, which can adversely affect treatment seeking, quality of care, and patient outcomes Our overall hypothesis is that an integrated management of ALD and AUD will improve clinical outcomes in patients with sAH. Aim 1. In the current study, we propose a sequential, multiple assignment, randomized trial to assess the safety and efficacy of integrated therapies in sAH. The integrated intervention includes a novel IL-22 fusion protein, compared to daily prednisone for 28 days with a Day-7 Lille stopping rule; survivors of the first 7 days will be re-randomized to either acamprosate, followed by a motivational interview (MI), and sessions of motivational enhancement therapy (MET), compared to usual care for AUD. Acamprosate is among the safest FDA-approved therapies for AUD, but its efficacy has not been evaluated for sAH. A composite measure of mortality, liver, and alcohol use outcomes at 6 months will be the primary endpoint. Aim 2. Build a platform for biosamples, data repositories, and patient registries to support site-specific and networkwide ancillary studies. These proposed studies will leverage the existing resources of AlcHepNet to evaluate the clinical impact of integrated ALD/AUD treatment in a diverse cohort of patients.

NIH Research Projects · FY 2025 · 2018-08

PROJECT SUMMARY Epigenetic mechanisms are increasingly recognized as critical regulators of gene expression and other essential cellular functions in health and disease. Among these regulators, the MBD2-NuRD chromatin remodeling complex has been shown to be central to the silencing of fetal hemoglobin expression in adult erythropoiesis, as well as the survival and growth of cancer cells. As reactivation of fetal hemoglobin is of proven therapeutic benefit in sickle cell anemia, the central and long-term goal of this project is to discover small molecules and cyclic peptides that can disrupt protein-protein interactions in the MBD2-NuRD complex that will lead to the development of much-needed new therapy for the vast number of sickle cell anemia patients who will not benefit in the foreseeable future from gene therapy or stem cell transplantation. This goal will be pursued through the following specific aims: 1) To determine the cellular effects of mutations that disrupt the association of the GATAD2A CR-2 domain and the C-terminal domain (CTD) of CHD4 of the NuRD holo-complex and disrupt its interaction with MBD2, as well as effects mutations that disrupt the interaction between the MBD2 intrinsically disordered domain (IDR) and the histone deacetylase subcomplex (HDCC) of NuRD and the resultant effect of these mutations on fetal hemoglobin (HbF) expression. 2) To characterize in molecular detail the structural domains of these key interactions to facilitate discovery of small molecules that bind tightly to the CHD4-CTD pocket domain and disrupt its interaction with the GATAD2A CR-2 domain and those that bind tightly to the HDCC pocket domain to disrupt its interaction with the MBD2 IDR, thus in either case disrupting the NuRD holo- complex. The experimental approach employs a real-time and iterative feedback of a combination of detailed structural determination of the involved protein-protein interfaces, precise base-specific gene editing to disrupt these interactions in adult phenotype erythroid cells, comprehensive screening for discovery of small molecules that disrupt the interactions, and testing the effects of disruption of the interactions on Hb F expression and other cellular effects in erythroid cell culture assay systems and an animal model of primary human erythropoiesis. These experiments will advance the goal of developing effective new agents for treating sickle cell anemia and may also advance efforts to develop improved therapy for resistant cancers.

NIH Research Projects · FY 2025 · 2018-06

Anaplasma phagocytophilum (Ap) is an obligate intracellular bacterium that causes the emerging and potentially fatal infection, human granulocytic anaplasmosis (HGA). The microbial-host interactions that facilitate Ap intracellular proliferation and dissemination have remained poorly characterized. We uncovered a novel role for the host bioactive sphingolipid, ceramide-1-phosphate (C1P), as a regulator of Golgi fragmentation. Specifically, C1P activates a PKC/Cdc42/JNK signaling axis that phosphorylates GRASP55 (Golgi reassembly stacking protein 55 kDa) to destabilize the trans-Golgi network (TGN) and amplify TGN anterograde traffic. We determined that Ap infection upregulates C1P synthesis and induces Golgi fragmentation in a C1P signaling-dependent manner. Multivesicular bodies (MVBs) are endosomal sorting stations that receive Golgi traffic. MVB limiting membrane invagination and scission deliver cargo into the MVB in intraluminal vesicles (ILVs). ILV membranes are enriched in cholesterol, sphingolipids, and sphingolipid metabolic enzymes that promote cholesterol release from ILVs. MVB fusion with the plasma membrane releases ILVs as exosomes, which induce a battery of responses in recipient cells including signaling, immunity, and inflammation. The importance of exosome- mediated cell-to-cell communication in infectious disease is just beginning to be appreciated. We discovered that Ap resides in a pathogen-modified MVB that receives sphingomyelin-rich TGN cargo as ILVs. The bacterium coopts MVB lipid metabolic machinery to parasitize sphingolipids and cholesterol, which is essential for its growth and conversion from its replicative to infectious form. Consistent with MVB exosome release, the Ap vacuole fuses with the plasma membrane in a Rab27a-dependent manner to disperse infectious progeny to naïve cells. We also found that Ap alters exosome content. In this competitive renewal, we will interrogate our hypothesis that Ap induces C1P to destabilize the Golgi and promote TGN-to-ApV trafficking of SM-rich vesicles that enables Ap to parasitize host lipids for proliferation and dissemination. We will also test our hypothesis that Ap modulates the proteomic and lipidomic content of ILVs that, when released as exosomes together with progeny bacteria, synergistically benefit infection of naïve cells and/or contributes to immunopathology associated with HGA. Completing the Aims herein will yield one of the most refined models for intracellular bacterial pathogenesis, further illuminate our newly discovered roles of C1P as both a regulator of Golgi stability and microbial target for host modulation, and further understanding of how exosomes contribute to pathogenic processes.

NIH Research Projects · FY 2025 · 2018-04

Abstract Congenital myotonic dystrophy (CDM), the most severe form of myotonic dystrophy, causes muscle weakness, breathing problems, and feeding difficulties at birth. During childhood affected individuals experience intellectual impairment and gastrointestinal issues while, in contrast, muscle strength and weakness improve. Muscle symptoms associated with adults with myotonic dystrophy, including myotonia and fatigue, are not observed until individuals reach adolescence. In the previous proposal period, the investigators clinically defined this triphasic pattern of motor involvement via enrollment of over 100 children in a comprehensive clinical study to evaluate measures of physical function over 12 months. In adults with myotonic dystrophy, a toxic RNA repeat expansion leads to global dysregulation of RNA splicing. Within the previous proposal period we performed RNA sequencing on 36 congenital myotonic dystrophy muscle biopsies from individuals 2 weeks to 16 years of age. We found that the severity of RNA mis- splicing mirrored the triphasic course of muscle symptoms captured clinically; children in early childhood showed improvement in RNA splicing dysregulation that regressed in adolescence. This result was bolstered by the inclusion of biopsies sampled from individuals at two ages across development. While these observations correlate with the clinical course of CDM, the mechanisms responsible for these dynamic shifts in mis-splicing remain unknown. This proposal is designed further clarify and define the molecular mechanisms responsible for the clinical and molecular progression of CDM. In Aim 1, we will enroll additional children with CDM that have acquired a previous muscle biopsy in a clinical follow-up study to acquire both longitudinal assessments of muscle function and a secondary muscle biopsy. RNA sequencing will be performed and mis-splicing and gene expression quantified to validate the course of CDM disease pathogenesis. In Aim 2 and 3, we will evaluate two potential molecular mechanisms based on our prior data that may contribute to the complex trajectory of CDM disease. In Aim 2, we will define the proliferative and regenerative capacity of CDM muscle stem cells across pediatric development and the contribution mediated via the IGF2 mitogenic signaling axis. In Aim 3, we will define how expression of core spliceosomal patterns contribute to the unique mis-splicing signatures observed within cohorts of CDM individuals. At the completion of this project, we will have validated the clinical and molecular course of CDM disease progression across pediatric development and performed experiments vital to understanding the mechanisms that contribute to this dynamic pattern. By better understanding the pathogenesis of CDM, we both allow access of these children to forthcoming disease modifying therapies in myotonic dystrophy, as well as, identify new therapeutic targets for drug development.

NIH Research Projects · FY 2025 · 2017-09

PROJECT SUMMARY Adeno-Associated Virus (AAV) has evolved the property to integrate into its host genome exploiting a unique mechanism shared by organisms in all domains of life to process single stranded DNA during DNA replication, bacterial conjugation and special cases of transposition. The large AAV Rep proteins Rep68/Rep78 are the key players that carry out this process using two multifunctional domains that include an origin binding domain (OBD) that binds DNA specifically and belongs to the family of HUH endonucleases; and a SF3 helicase domain. Integration is contingent on the binding of Rep68/Rep78 to the integration site AAVS1, promote its melting and perform a strand-specific transesterification reaction in the single-stranded region that has been extruded during the melting step. Little is known about the molecular details of this process and our long-term goal is to determine the molecular mechanism of site-specific integration mediated by AAV Rep proteins. In this proposal we will focus on uncovering the mechanisms of Rep mediated DNA melting, nicking and packaging using a combination of structural biology methods that include X-ray crystallography, and single- particle reconstruction Cryo-EM coupled to biochemical, biophysical and in vivo assays.

NIH Research Projects · FY 2026 · 2017-07

The CORE-EM Alliance (COalition for REsearch in Emergency Medicine) brings to SIREN six, highly experienced research infrastructures, each with their own spokes, partnering as an innovative, single, super-hub within the SIREN network. The goal of CORE-EM is to provide rapid implementation and high-quality performance in large pragmatic clinical trials to study acute conditions including neurologic, cardiovascular, respiratory, hematologic, infectious disease, and trauma-related emergencies. CORE-EM was funded as a SIREN Hub in 2017 to facilitate excellence in resuscitation research. Supporting a >70-million-person catchment area across the US, CORE-EM prioritizes access to clinical trials for individuals across the US. CORE-EM is ranked #2 for enrollments within SIREN. CORE-EM’s MPI leadership has successfully collaborated for 15+ years to execute clinical trials. MPIs serve on SIREN Governance committees and represent acute care research nationally within the Society for Academic Emergency Medicine, American College of Emergency Physicians, Society for Critical Care Medicine, and through service on NINDS, NCATS, and AHRQ National Advisory Councils. CORE-EM MPIs have assisted in authoring SIREN clinical trials and are actively developing new proposals, such as to study eCPR/ECMO in the Emergency Department (ED), ECPR INSIGHT. CORE-EM has successfully deployed trials in cardiology, neurosurgery, infectious disease, hematology, and intensive care. This includes implementing the first two EFIC trials in the states of Rhode Island and Florida. Co-investigators engage across specialties to ensure excellence in care from scene of injury, through the ED, operating rooms, ICUs, and into rehabilitation. Residents and junior faculty are mentored in the CORE-EM Alliance, as co-investigators and site-PIs. CORE-EM is committed to conducting rigorous trials, training the next generation of physician scientists, and providing outstanding clinical care through excellence in research, discovery, and implementation science.

NIH Research Projects · FY 2026 · 2017-07

Abstract Macrophage polarization enables macrophages adapt to various microenvironmental cues and adopt a spectrum of functional phenotypes. These are generally classified into classically activated (pro-inflammatory, M1) and alternatively activated (pro-healing, M2) categories. The M1/M2 balance determines the extent and severity of inflammatory responses and tissue damage. However, the signaling pathway(s) and cues driving macrophage polarization in the oral cavity's infectious milieu are largely unknown. Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) are transcriptional co-activators implicated in inflammation regulation and macrophage polarization in a context-dependent manner. Despite the observation of aberrant YAP1/TAZ expression in gingival tissues from patients with periodontitis, the triggers and mechanisms of YAP1/TAZ signaling in regulating macrophage polarization in periodontium remain unclear. Our previous R01 study unveiled the suppressive role of serum- and glucocorticoid- inducible kinase (SGK) 1 in the immune response to the oral pathogen. Using Porphyromonas gingivalis (Pg) as a model organism, in this renewal project, we aim to investigate the regulation of YAP1 by SGK1 in Pg-stimulated macrophages and its subsequent impact on macrophage polarization, thereby revealing a novel regulatory module, SGK1-YAP1, in periodontal inflammation. Preliminary results showed that (i) SGK1 inhibition remarkably decreases YAP1 phosphorylation and increases its nuclear retention in Pg-stimulated macrophages; (ii) Pg infection enhances YAP1 phosphorylation and promotes its retention in the cytoplasm, and the ubiquitin-proteasome inhibitor further augments YAP1 expression; (iii) YAP1 inhibition suppresses macrophage polarization towards M1 phenotypes; and (iv) sgk1 deficiency increases nuclear YAP1 expression and the M1/M2 ratio in the gingival tissue from mice subjected to repeated Pg infection. These findings lead to our hypothesis that YAP1 cytoplasmic retention and expression are controlled by SGK1 in response to Pg challenge. This control mechanism limits macrophage polarization towards M1 phenotypes, thereby preventing tissue damage and periodontal inflammation. To test this hypothesis, we will (i) determine and characterize the regulation of YAP1 by SGK1 in innate immune cells in response to Pg; (ii) functionally dissect SGK1-YAP1 signaling pathways in macrophage polarization upon Pg challenge; (iii) assess the effect of SGK1- YAP1 signaling in vivo on macrophage polarization and disease process induced by Pg using murine infection models. Successful completion of this study will identify SGK1 as a novel regulator of YAP1/TAZ signaling, functioning through dual mechanisms of phosphorylation and ubiquitination. For the first time, we will delineate the alternative macrophage polarization mediated by Pg via SGK1-YAP1 signaling. This work not only advances our understanding of macrophage polarization in periodontium but also could inform studies aimed at identifying novel targets to restore macrophage subset balance, thus ameliorating/preventing Pg-induced tissue destruction.

NIH Research Projects · FY 2026 · 2017-04

Project Summary: High-risk neuroblastoma (NB) is responsible for ~13% of pediatric cancer-related deaths. Venetoclax (VEN) is a BCL-2 inhibitor that has revolutionized adult hematological cancer care. Unique among solid tumors, ven has demonstrated promising pre-clinical activity in MYCN-amplified NB, but likely will require rational combinations for clinical activity. In our previous funded work, we have demonstrated VEN makes an effective drug partner across several combination therapies (e.g. Lochmann et al. Science Translational Medicine 2018; Dalton et al. Molecular Cancer Therapeutics 2021). In this renewal application, we focus on two clinically translational combination therapies involving two new classes of drugs, SHP2 inhibitors which target the MEK pathway, and BCL-xL targeting antibody-drug conjugate (ADC). In NB, one of the more intriguing discoveries recently has been the hyperactivation of the MAPK/MEK pathway, particularly in relapsed tumors. However, MEK inhibitors have not proven effective in preclinical studies of RAS/RAF wild-type NB, which makes up more than 95% of cases. Here, we demonstrate that in a high-throughput screen (HTS) of a SHP2 allosteric inhibitor, SHP099, that NB are the most sensitive group among all cancers, while MEK inhibitors are relatively ineffective. We provide preclinical evidence that these inhibitors are favorable to MEK inhibitors through a series of experiments. Importantly, SHP2 inhibitors form a rational combination partner with VEN through modulation of BCL-2 family proteins. Lastly, through efforts like a HTS of the co-BCL-2/BCL-xL inhibitor, navitoclax (Ham et al. Cancer Discovery 2016), we have demonstrated MYCN-amplified NB are among the two most sensitive solid tumor cancers, mirroring sensitivity to the VEN data, but with marked enhancement of sensitivity through dual targeting of BCL-xL. This concept has been previously clinically unattainable due to on-target thrombocytopenia from BCL-xL inhibition in platelets. To circumvent this problem, AbbVie has developed a BCL-xL targeting ADC ABBV-155. We find the antigen, B7-H3 (CD276), is widely expressed in NB, and, as a result, combining ABBV-155 with VEN is effective in MYCN-amplified NB. Specific Aims: Specific Aim 1: Evaluate the efficacy and mechanism of activity of SHP2 inhibition + venetoclax in MYCN- amplified neuroblastoma models Specific Aim 2: Evaluate the efficacy and mechanism of activity of platelet-sparing BCL-xL inhibitors + venetoclax in MYCN-amplified neuroblastoma models Study Design: We will further characterize the high sensitivity of SHP2 inhibition with VEN and ABBV-155 with VEN in vitro and in genomically-annotated patient-derived xenograft (PDX) orthotopic models of MYCN- amplified NB. We will perform BH3 profiling (BP) to further evaluate the role of BCL-2 proteins in sensitivity and investigate whether BP and dynamic BP will help us identify sensitive and resistant NBs to each combination.

NIH Research Projects · FY 2025 · 2016-07

Summary Nonalcoholic steatohepatitis (NASH), the most common cause of chronic liver disease in the Western world and a major global health problem, leads to cirrhosis and hepatocellular carcinoma (HCC). The lack of an optimum therapy mandates better understanding of the molecular pathogenesis of NASH, identification of regulatory molecules and development of targeted therapeutic approaches. Studies, supported by previous cycle of this renewal application, unraveled a novel role of the oncogene Astrocyte elevated gene-1/Metadherin (AEG-1/MTDH) in promoting NASH. AEG-1 induces steatosis by inhibiting PPARα, hence fatty acid β-oxidation (FAO), and promoting translation of fatty acid synthesizing enzymes thus augmenting de novo lipogenesis (DNL). Additionally, AEG-1 activates NF-κB, a master regulator of inflammation. Thus AEG-1 plays a key role in NASH and NASH-HCC. We established the therapeutic efficacy of a hepatocyte-targeted nanoparticle delivering AEG-1 siRNA to inhibit HFD-induced NASH in mice. Macrophages play a pivotal role in the pathogenesis of NASH by regulating the functions of adipocytes and hepatocytes. We recently documented that AEG-1 plays a vital role in regulating macrophage activation and mice with deletion of AEG-1 in myeloid cells (AEG-1∆MAC) are profoundly resistant to N-nitrosodiethylamine (DEN)-induced inflammatory HCC. Our preliminary studies now document that AEG-1∆MAC mice are also resistant to HFD-induced NASH, and identify that a novel post-translational modification, cysteine palmitoylation, is required for protein translation and NF- κB activation functions of AEG-1. These observations allow us to hypothesize that macrophage AEG-1 promotes NASH by regulating adipocytes and hepatocytes, cysteine palmitoylation regulates AEG-1 functions which contribute to NASH development, and targeted inhibition of AEG-1 in macrophages and hepatocytes might be an effective therapeutic intervention for NASH. Experiments using relevant mouse models and human cells will be performed to address these hypotheses. Our proposed studies will unravel a novel role of AEG-1 in macrophages and a novel post-translational modification regulating AEG-1 function. Multiple clinical trials document efficacy of inhibiting expression of genes in the liver by RNA interference (RNAi) strategy in a variety of diseases thereby establishing potential application of this strategy to manage NASH in the clinics. Our proposed studies thus have important mechanistic and translational significance.

NIH Research Projects · FY 2025 · 2014-08

Project Summary – Overall Alcohol use disorders (AUDs) represent a major public health burden. Genetic risk factors contribute significantly to the susceptibility to develop AUDs and are likely to be a result of many variants that each contribute modestly to risk. Genetic studies in animal models and humans to date have made slow progress in identifying individual genetic risk variants. This proposal for a P50 Alcohol Research Center presents a novel and highly integrated overall design in which we focus both on gene discovery and on functional analysis of the biological bases underlying risk for AUDs. This application is a renewal of our currently funded P50 that supports the VCU Alcohol Research Center (VCU-ARC), which was first funded with a P20 Developmental Center grant in 2009, and has been continuously funded since. We have a rich history of collaborative studies, and we have made significant progress over the past 14 years. Here we seek to both continue aspects of our current studies and to extend our work into new areas. Our approach continues to be innovative and significant due to three novel features: 1) A focus on gene networks contributing to AUD-related phenotypes and ethanol response behaviors; 2) A cross-species genetic and genomics analysis to validate candidate genes and networks and examine the underlying biology affecting ethanol response behaviors; and 3) A highly integrative and collaborative Center design with rapid data sharing across projects through a cross-species analysis pipeline to provide ranked gene lists, networks, and biological processes for further experimental validation in the component projects. We request five years of support for five Research Projects performing genetic studies in worms, flies, mice, and humans. Two projects will pursue new areas of study, and three others will extend their current projects with novel areas of investigation. Two projects will be in human genetics using state-of-the-art statistical approaches to leverage the power of large genome-wide association and exome sequencing studies on phenotypes significantly associated with AUDs. Three projects will use animal model organisms to develop and test hypotheses about the biological underpinnings of the effects of genes on alcohol response behaviors. All projects will be supported by an Administrative Core containing statistical and modeling support and a Behavior Core containing both a high- throughput invertebrate genetic screening function as well as a high-resolution analysis of the effects of candidate genes on mouse behavior. The scientific work proposed in these Projects and Cores is clearly greater than the sum of its parts, due to the highly interactive structure of the VCU-ARC components. The VCU-ARC is well positioned to continue to make major contributions to the advancement of our understanding of the etiology of AUDs and subsequently their prevention and treatment.

NIH Research Projects · FY 2025 · 2014-08

PROJECT SUMMARY Virginia Commonwealth University (VCU) Massey Comprehensive Cancer Center (Massey) will serve as the primary component site for an NCI Community Oncology Research Program (NCORP) Community Site (UG1 award in partnership with nine collaborating community affiliate sites in the Commonwealth of Virginia. This proposal emphasizes the urban and rural populations available to VCU/Massey’s NCORP. This community-based NCORP, focused on increasing the availability of NCI clinical research trials to all populations, was initially funded in 1990 as a Community Clinical Oncology Program and has been continuously funded since. The VCU/Massey NCORP has affiliations with six Research Bases (Alliance for Clinical Trials in Oncology, Children’s Oncology Group, ECOG-ACRIN Cancer Research Group, NRG Oncology, Wake Forest NCORP Research Base, and University of Rochester NCORP Research Base). This proposal focuses on the urban and rural populations available to VCU/Massey’s NCORP and on accruing significant numbers of participants in cancer control and prevention, treatment/imaging, and cancer care delivery clinical research studies. This application describes VCU/Massey’s NCORP collaborations with the Research Bases as well as the working relationships between the primary site’s investigators, research staff, support personnel, and the affiliate sites. Accordingly, the specific aims of this proposal are to: (1) Increase the overall enrollment to NCI-approved studies, with participation representative of the catchment area, with a strong focus on cancer control research (CCR), cancer prevention research (CPR), and cancer care delivery research (CCDR), in addition to cancer treatment research (CTR); (2) Collaborate with the NCORP Research Bases by (a) providing insight into clinical significance during concept development, (b) identifying care imbalances in local populations served by VCU Massey’s NCORP that could be studied, and (c) providing input on feasibility concept and protocol development; (3) Exceed the required annual minimum participation in CCDR protocols; (4) Participate in biospecimen collection for biobanks that serve as scientific resources for NCORP Research Bases; and (5) Participate in NCORP initiatives to document screening efforts for clinical trial enrollment and to address differences in cancer health outcomes. The proposed revision to extend the VCU/Massey NCORP award is relevant to NCI’s mission as it will continue to advance scientific knowledge and help all people live longer, healthier lives.

NIH Research Projects · FY 2025 · 2013-09

Project Summary Ubiquitous and conserved molecular chaperones Hsp70s and Hsp110s form one of the most essential chaperone machineries in maintaining protein homeostasis (proteostasis). However, the molecular mechanisms and exact role of Hsp110s in this chaperone machinery remain largely unclear. As distant homologs of Hsp70s, Hsp110s are both independent chaperones and co-chaperones for Hsp70s. As independent chaperones, Hsp110s demonstrate a unique high chaperone activity in preventing aggregation of denatured proteins, the holdase activity. As co-chaperones, Hsp110s function as the major nucleotide-exchange factor (NEF) for Hsp70s. Although the importance and mechanism of the NEF activity is well-characterized, the function and involvement of the holdase activity is almost completely unknown primarily due to the lack of any available approach to disrupt this holdase activity without affecting the NEF activity. Msi3 is the sole and essential Hsp110 in Candida albicans, the most prevalent cause of fungal infections in humans. Our preliminary studies have identified a novel inhibitor for Msi3, named 2H. Excitingly, 2H specifically abolishes the holdase activity while leaving the NEF activity largely intact. Importantly, 2H was seen to reduce protein folding both in vitro and in vivo, providing the first direct evidence to support the importance of the holdase activity of an Hsp110 in the Hsp70s/Hsp110s chaperone machinery. In addition, as the first inhibitor for fungal Hsp110s, 2H effectively eliminates the growth and viability of C. albicans with limited toxicity in human cells, supporting that Hsp110s are an important target for designing novel and potent therapeutics for fungal infections and 2H may represent a promising lead compound for a new class of antifungals for future medicinal chemistry efforts. Taking advantage of the unique selectivity of 2H, the overall objective of this proposal is two-fold: 1) to characterize the elusive molecular mechanism and biological function of the holdase activity of Hsp110s, and 2) to increase mechanistic understanding of Hsp110s as a new therapeutic target for fungal infections. Accordingly, we propose two Specific Aims. Aim 1: Characterize the in vivo function of Hsp110's holdase activity in proteostasis using 2H. Taking advantage of the powerful and facile genetics available to the yeast Saccharomyces cerevisiae, we aim to directly analyze the conserved functions of Hsp110s' holdase activity in two essential in vivo processes in proteostasis: protein folding and import into endoplasmic reticulum. We expect to identify and characterize endogenous substrates for Hsp110s for the first time. Aim 2: Elucidate the inhibitory mechanism via structural characterization of 2H in complex with Msi3. We aim to solve the structures of Msi3, both alone and complexed with 2H, which will reveal the specific binding interactions between 2H and Msi3 and the mechanism of 2H's inhibition of Msi3. We expect that our innovative proposal will make paradigm-shifting discoveries on the function and mechanism of Hsp110s in the Hsp70s/Hsp110s chaperone machinery and pave a solid foundation for our future effort to develop novel and selective antifungals by targeting Hsp110s.

NIH Research Projects · FY 2025 · 2013-08

PROJECT SUMMARY Identification of bacterial virulence factors has been the epicenter in study of host-pathogen interactions. However, only a handful of virulence factors have been functionally characterized in the oral bacterium Treponema denticola (Td), an important and yet understudied oral pathobiont that is associated with periodontitis and other forms of oral infections. Growing evidence also shows that Td is implicated in systemic illnesses such as Alzheimer’s disease and oral cancer. During the last funding cycle, by using a multidisciplinary approach of genetics, biochemistry, cell biology, immunology, structural biology, and animal models, we have elucidated the role of TDE0362 (a cysteine protease), TDE0471 (a sialidase), and protein glycosylation in the pathophysiology of Td. Building upon this momentum, this renewal application focuses on sialidase and three newly identified virulence factors including a new cystalysin (TDE2410) and two filamentation-induced-by-cyclic-AMP (Fic) enzymes (TDE0061/TDE0233). Our preliminary results demonstrate that TDE2410 has hemolysin activity and TDE0061 and TDE0233 are toxic to both yeast and mammalian cells. Based on these results, we hypothesize that these newly identified virulence factors play critical roles in the pathophysiology of Td. To test this, three specific aims are proposed. Aim 1 seeks to investigate how Td employs sialidase to disarm the complement system and alter TLR2/TLR4-mediated innate immune response. If successful, it will improve our understanding of how bacterial pathogens modulate host innate immune defense via desialylation. Aim 2 focuses on cysteine metabolism and its role in Td. Cystalysin is a hallmark virulence factor of Td. It metabolizes cysteine producing pyruvate, ammonia, and H2S. Td lacks a de novo biosynthesis pathway of cysteine and thus needs exogenous cysteine for its growth. However, the mechanism by which Td acquires thiol amino acids remains elusive. We recently identified a putative cysteine transporter (TDE1668) and a new cystalysin (TDE2410). If successful, Aim 2 will provide mechanistic insights into understanding the role of cystalysins and cysteine metabolism in Td. Aim 3 proposes to elucidate the role of two Fic proteins in Td. Some bacterial pathogens have evolved a unique mechanism to hijack host signaling pathways (e.g., the Rho family of small GTPases) through Fic-mediated AMPylation, induce pathogenic effects, and promote bacterial infection. Thus far, Fic enzymes have not yet been studied in any oral pathogens. Therefore, the study in Aim 3 will open a new avenue to investigate the role of Fic proteins in oral pathogens. Completion of this project will not only advance Td research but also provide new directions and techniques to study other oral pathogens and their roles in the pathogenesis of periodontitis

NIH Research Projects · FY 2025 · 2013-06

Summary Nitrite and nitric oxide are widespread and robust signaling modulators that are emerging as potential new antibacterial therapeutic agents. The oral cavity has particularly high concentrations of nitrite, which can reach 1mM. Oral microorganisms have adapted to survive such high nitrosative stress exposure and, we expect, that disruption of these adaptation mechanisms will reduce growth and survival of bacteria in the oral environment. We know that Porphyromonas gingivalis, a periodontopathogen, has high tolerance of nitrosative stress. However, the complex signaling pathways setting the basis of this tolerance are yet to be determined in in this bacterium as well as in other oral bacteria. Using whole genome expression analysis we have identified hcp encoding newly re-designated S-nitrosylase as the most dramatically upregulated gene under nitrosative stress. Furthermore, we demonstrated that regulation of Hcp is dependent on an FNR- like regulator, HcpR, that employs novel hemin-dependent mechanism to sense nitrosative stress. We hypothesize that the HcpR-Hcp system is central for adaptation of P. gingivalis to nitrosative stress. Thus, we will first define the molecular mechanisms of P. gingivalis sensing nitrosative stress through determination of the structural and biochemical characteristics of HcpR. Since adaptation to nitrosative stress involves a novel enzymatic activity mediated by Hcp, we will characterize the Hcp-mediated S-nitrosylome using proteomic approaches. In addition, we will characterize the mechanism P. gingivalis Hcp employs to mediate protection against nitrosative stress. Finally, we will investigate the contribution of other putative regulatory and effector proteins in nitrosative stress defense in P. gingivalis. It is noteworthy, that we will verify the contribution of the mechanisms under host-pathogen setting. This knowledge will provide the tools to design agents that can compromise the defense mechanisms of the periodontopathogen and turn endogenous human host nitrite and nitric oxide into a weapon that inhibits growth of the bacterium and, ultimately, we can exploit it to treat periodontal disease. We predict that this work will shed light on nitrosative stress signaling mechanisms in a variety of other bacteria that carry similar nitrosative stress protection mechanisms to those in P. gingivalis.

NIH Research Projects · FY 2026 · 2011-09

Project Summary This proposal seeks to better understand the contribution of cortical inhibitory interneuron subtypes to network dysfunction after mild traumatic brain injury (mTBI) utilizing a well controlled and characterized mouse model, the central fluid percussion injury. Our group has identified significant and differential dysfunction in neocortical interneuron subtypes after mTBI in this model. Parvalbumin interneurons (PV) modulate gamma oscillations recorded from EEG that is critical for sensory perception. The PV are particularly vulnerable after injury, with 10% being axotomized and the output from PV to local pyramidal neurons being significantly reduced. In contrast somatostatin-containing interneurons (SOM) show little axotomy and have an increased output onto local pyramidal neurons. In other disease models the link between the ratio of PV:SOM and altered gamma levels has been well established. We hypothesize that injury also alters this ratio and that alteration underlies the increase in resting gamma and the decrease in evoked gamma that we and others have observed. We will test that here using chemogenetics and mutant mice with altered PV:SOM ratios. In addition we will test the link of that altered gamma to an increased sensitivity to touch and lowered pain threshold. We further hypothesize that the reason PV are vulnerable is due to the activation of microglia which subsequently degrade the perineuronal nets (PNN) that normally surround the PV. Once the PNN are removed PV function is likely reduced due to reactive oxygen species. Each aspect of these hypotheses will be tested by depleting microglia and by treating the oxidative stress with N-Acetylcysteine. Outcome measures will include the power of the gamma recorded from EEG, pain threshold via von Frey filaments, whisker nuisance test score, the percent of axotomized PV and SOM interneurons, the intracellularly recorded function of the PV and SOM and the level of output from PV and SOM. These studies will determine if this cellular dysfunction underlies the abnormal network function and altered cognition after mTBI.

NIH Research Projects · FY 2025 · 2010-09

The future of biomedical research depends on a robust pool of well-trained scientists who are equipped to investigate the priority health issues of the 21st century. In addition, it is necessary to cultivate a cadre of enthusiastic, ambitious, and creative educators who can inspire their students to pursue careers in research. Because postdoctoral training typically focuses on research, future educators face the challenge of developing both the teaching skills and the research portfolio necessary to be competitive for faculty positions. As a research-intensive institution with 18 Schools and Colleges including medicine, pharmacy, public health, nursing, health professions, engineering, and education, Virginia Commonwealth University (VCU) is uniquely positioned to provide this comprehensive training. The VCU IRACDA program has collaborated with Virginia State University (VSU) since 2010, and is designed to address this challenge with two major goals. The first is to prepare postdoctoral fellows for faculty positions through career development in both cutting edge research and advanced teaching skills. VCU IRACDA scholars perform research under the guidance of experienced mentors, and participate in hands-on mentored teaching at our partner university VSU. The second goal of VCU IRACDA is to enhance collaborations between VCU and VSU, by expanding the VSU curriculum and promoting research opportunities for students and faculty. These goals will be accomplished through the following Specific Aims: (1) Annually identify at least 6 highly qualified applicants and recruit 2 outstanding postdoctoral scholars to the 3- year VCU IRACDA program (steady state 6 scholars); (2) Provide VCU IRACDA postdoctoral fellows with multifaceted and intensive career development training in research and teaching; (3) Enhance the curricular offerings and research environment at VSU through course delivery with a strong foundation in current research trends and methodologies; and (4) Continue our rigorous evaluation and tracking system for longitudinal follow-up of VCU IRACDA program impacts on scholars and on VSU students and faculty members.

NIH Research Projects · FY 2026 · 2010-03

Program Director/Principal Investigator: Kendler, Kenneth S This second competitive renewal seeks to continue our innovative and productive research program which seeks to understand the etiology of drug use disorders (DUD) utilizing data available on the entire population of Sweden of unparalleled completeness and depth. We have eight specific aims: i) to use a newly developed genetic risk score for DUD for the entire Swedish population to explore boundaries of the DUD phenotype, model gene x environment interactions and clarify origins of DUD-related comorbidities; ii) to understand the impact of social roles/relationships (e.g., marriage, divorce, parenthood) on risk and resilience for DUD; iii) to explore the etiology of opiate use disorder (OUD) by comparing the social, familial and genetic risk factors OUD and non-opiate DUD, by clarifying the etiologic role of opiate prescriptions in OUD development and to identify clinically meaningful subtypes of OUD, especially an iatrogenic form; iv) to investigate the impact of institutional settings on subsequent DUD, focusing on military service and incarceration; v) to evaluate the impact of synthetically constructed populations compared to actual Swedish populations in the evaluation of DUD and OUD utilizing FRED (A Framework for Reconstructing Epidemiological Dynamics) developed by our collaborators at the Public Health Dynamics Laboratory (PHDL) at University of Pittsburgh; vi) to improve our contagion models for the transmission of DUD by taking advantage of new data available in Swedish registries on high school attendance, college attendance and workplace, improved Geographic Information Systems and FRED; vii) to explore the association between stressful and traumatic events including COVID-19 exposure severity and stress-related disorders (e.g., posttraumatic stress disorder [PTSD]) with DUD onset and recurrence and examine moderators of impact of both exposures and stress-related disorders on DUD and viii) using a calibrated, detailed version of the Swedish population in FRED, to evaluate the predicted impact of a range of mitigation strategies, based on the relationships defined by our earlier work and new findings from the above aims. We will, for many of these aims, attempt to clarify the causal nature of the observed associations using statistical and natural experimental methods. We will use comprehensive data from multiple nationwide data sources in Sweden on 11.8 million men and women to accomplish these goals. Applying the deep expertise of our research groups at Virginia Commonwealth, PHDL and Lund University in drug abuse research, social and genetic epidemiology, causal inference and epidemiological model development to a uniquely powerful sample, we expect this study to have important implications for DUD research, prevention and policy.

NIH Research Projects · FY 2026 · 2009-07

Project Summary G protein-coupled receptors (GPCRs) are key membrane proteins involved in transduction of external signal across the cellular membrane into the cytoplasm of target cells. Related to their quaternary structure, although this concept still remains a matter of intense speculation and debate, it is particularly intriguing the plausible ability of class A GPCRs to assemble as heterodimers or heteromers that exhibit distinct pharmacological, trafficking and functional properties as compared to their parent monomeric or homodimeric/homomeric forms. As such, GPCR complexes may represent novel drug targets with extensive therapeutic potential. However, many questions still remain open about the role of receptor complex formation in the dynamics and behavior of GPCRs. Classical psychedelics, including psilocybin, mescaline and LSD, profoundly affect processes related to perception, cognition and sensory processing. Over the past decade, psychedelic compounds have emerged as potentially transformative therapeutics for a variety of otherwise intractable neuropsychiatric conditions. Despite these striking effects, their acute symptoms and uncontrolled recreational use potential preclude the routine use of psychedelics in daily clinical practice. Additionally, although these results have interesting implications for psychiatry research and therapeutics, many questions regarding the molecular target and neural circuit mechanism of action, safety, and efficacy of psychedelics as fast-acting therapeutics still remain open. It is therefore imperative to understand the biology and pharmacology behind their therapeutic mechanisms as well as expose potential pitfalls in their widespread use as treatment. Over the past 15 years of this grant, we have accumulated several lines of evidence indicating that class A Gq/11-coupled 5-HT2A receptor (5-HT2AR) and class C Gi/o-coupled metabotropic glutamate receptor 2 (mGluR2) are able to physically interact with one another and by so doing alter G protein coupling, sub-cellular localization and function. We showed that at least part of the cellular signaling and synaptic structural plasticity effects induced by psychedelic 5-HT2AR agonists require expression of mGluR2. The final goal of this competitive renewal is to expand our prior basic work dissecting functional crosstalk mechanisms between 5-HT2AR and mGluR2 as a GPCR heteromeric complex, to understand its role in psychedelic-induced circuit-specific synaptic and behavioral plasticity. Our central hypotheses are that i) mRNA transcripts encoding 5-HT2AR and mGluR2 are associated in vitro and ex vivo in mammalian cells, that ii) co-expression of 5-HT2AR leads to agonist-induced mGluR2-Ga protein complexes located intracellularly via GPCR heteromerization, and that iii) selective deletion of mGluR2 in frontal cortex pyramidal neurons projecting to specific subcortical target regions abolishes the effects of a single dose of psychedelic 5-HT2AR agonists on synaptic structural plasticity and acceleration of contextual fear extinction. Completion of this work may provide the rationale for the development and testing of plasticity-promoting 5-HT2AR-mGluR2 ligands as safe, effective and fast-acting treatments for several psychiatric disorders.