University Of Alabama At Birmingham

NIH Research Projects · FY 2025 · 2025-07

PROJECT SUMMARY/ABSTRACT: Exposure to early life stress (ELS), including abuse, neglect, and household dysfunction, significantly increases the risk of mental illness, chronic kidney disease, and cardiovascular disease (CVD) later in life. The previously characterized effects ELS and chronic disease development in adults may have their origins in ELS- dependent effects on composition and functions of the gut microbiota. The gut microbiota interact directly with the host’s immune and neurological systems and microbial derived metabolites have been shown to mediation cardiovascular function. My recently published research using a mouse model of ELS has determined that ELS alters the gut microbiota independent of maternal inheritance. This suggests ELS-medicated endogenous factors within the offspring are responsible for the ELS microbial phenotype. However, it remains unknown whether ELS-mediated changes in the gut microbiota play a direct role in the genesis risk factors for CVD. This proposal will address these knowledge gaps by identifying ELS-medicated factors that regulate the gut microbiota and elucidating microbial-mediated pathways that lead to increased CVD risk due to ELS. Adolescents and young adults with ELS have increased arterial stiffness and systemic vascular resistance. Using an established mouse model of ELS involving maternal separation, our novel data indicate that ELS is also associated with increased arterial stiffness in adolescent and adult mice. Furthermore, ELS induces superoxide production and endothelial dysfunction in adult mice. This suggests that vascular dysfunction is an important mediator of ELS-induced CVD risk. Our new data in mice show that ELS leads to reduced gut microbial diversity, lower circulating short-chain-fatty acids (SCFAs), and impaired gut barrier function during adolescence. Gut microbial diversity is negatively associated with arterial stiffness in women and reduced SCFAs are associated with hypertension and impaired gut barrier function. This suggests a role for the gut microbiota in ELS-induced vascular dysfunction, though exact mechanisms remain undefined. Therefore, the overall goal of this proposal is to elucidate mechanisms by which microbial metabolites mediate ELS-induced aortic stiffening and endothelial dysfunction and examine the potential of diet in the early intervention of CVD risk.

NIH Research Projects · FY 2026 · 2025-06

Arsine (SA), the most toxic form of inorganic arsenic is a potent chemical warfare (CW) agent. Although arsine was never used in the battlefield, concerns still exist that it may be used as a small-scale weapon during indoor public meetings or concerts. None-the-less arsine exposure in occupational settings due to accidental release is known among the industrial workers. Pathophysiology associated with inhaled arsine gas involves hemolysis of massive red blood cells that often leads to kidney failure and associated morbidity/mortality. Erythrocyte destruction leads to the release of hemoglobin (Hb) and heme into circulation, which subsequently accumulates in the tubular epithelium, causing acute kidney injury (AKI). However, the detailed molecular mechanisms of its toxic action are not fully defined and represent a major knowledge gap. Our preliminary data demonstrate that arsine gas exposure at 15 ppm for 1 h to C57BL/6 mice induced intravascular hemolysis as evidenced by bloody urine and dark red plasma, associated with a significant decrease in RBCs, hematocrit, and hemoglobin. Additionally, a significant induction of NGAL and KIM-1, the early and late respective biomarker of AKI in urine and kidneys were prominent. Utilizing an arsine-unrelated surrogate murine model of hemolysis, we show that mice treated with phenylhydrazine (PHZ), a potent hemolytic agent, significantly causes hemolysis along with an induction of AKI biomarkers, which is identical to that we observed in arsine gas-exposed mice. Thus, PHZ mouse model provides critical utility to determine the pathogenic molecular underpinnings of arsine-mediated hemolysis and associated kidney injury. Our preliminary data identified NOD1/2 as a key target in hemolysis- mediated kidney injury in both of these mouse models. NOD1/NOD2 are immune response sensors and can modulate inflammation and cellular injury. Two specific aims are proposed. In Aim-1, we propose to characterize a mouse model of arsine toxicity. Both dose-and time-dependent responses will be characterized. Biomarkers of AKI will be examined in urine, plasma/serum and kidney. Pro-inflammatory mediators will be examined in serum and kidney. In addition, lung and liver damage will also be examined cursorily by histopathological analysis to evaluate multi-organ damage by arsine exposure. This aim will help in selection of an optimum dose-and time- point to develop medical countermeasures (MCM) for arsine toxicity. Aim-2 will define the therapeutic targets of arsine toxicity. Here, we will first screen three NOD inhibitors for identifying the most efficacious nontoxic dose employing PHZ mouse model. Then, one best NOD inhibitor (identified from PHZ model) will be tested for its efficacy against arsine-mediated AKI and associated morbidity. Successful completion of studies proposed in this R21 grant will provide a fully characterized mouse model and a novel molecular target-based therapeutic drug agent as MCM against arsine. The efficacy of these MCMs against other surrogate hemolysis-related disorders such as autoimmune hemolytic anemia, sickle cell disease, β-thalassemia, paroxysmal nocturnal hemoglobinuria, hemolytic uremic syndrome etc. will help in getting faster FDA approval.

NIH Research Projects · FY 2026 · 2025-06

Project Summary/Abstract Levodopa (L-DOPA)-induced dyskinesia (LID) is a debilitating motor side effect of long-term use of Parkinson disease (PD) medication. Proportionally higher output of the basal ganglia direct pathway compared to the indirect pathway, resulting in hyperkinetic abnormal involuntary movements, is a circuit-level hallmark of LID. Once developed, LID is difficult to mitigate and grows in severity with each successive dose. Our work indicates that a subpopulation of D1 receptor-expressing medium spiny output neurons (D1-MSNs) are transcriptionally altered by the development and stable expression of LID in animal models. This transcriptional profile is reminiscent of that of hippocampal engram cells upon recall of an entrained stimulus. In addition, manipulation of these specific D1-MSNs has been shown to bidirectionally mediate LID expression. THese characteristics suggest that a specific subset of D1-MSNs may serve as engram cells for LID. However, the evolution of cellular and molecular changes that uniquely occur in these engram-like D1-MSNs in response to L- DOPA treatment across the time course of LID development have not been established to date. We have previously observed that epigenetic processes play a key role in the development of LID, though these processes have never been investigated in a cell type-specific manner. The critical next steps are identifying the unique transcriptional, physical, and physiological characteristics of L-DOPA-responsive D1-MSNs upon both acute and chronic L-DOPA exposure and determining the epigenetic mechanisms that may spur this process. The overall goal of the work proposed in this application is to utilize genetic approaches to establish an engram-like population of D1-MSNs utilizing a well-established preclinical model of LID in combination with a novel mouse model, allowing us to specifically target the cells which underlie LID. We will utilize a transcription-to-behavior approach to investigate cellular connectivity at the level of chromatin remodeling, transcription, cellular morphology and physiology, and behavior. Our hypothesis is that LID development is associated with remodeling of L-DOPA-responsive D1-MSNs (Aim 1), mediated by a shift in chromatin availability and corresponding transcriptional networks (Aim 2), that underlies the transition from the acute to chronic LID state. To date, there are no available therapies to halt LID development. The results from this research will indicate targets for LID- mitigating therapies to prolong the usefulness of L-DOPA, the gold standard of PD therapy for over 50 years.

NIH Research Projects · FY 2025 · 2025-06

Abstract The dysfunction and death of pancreatic β cells are key features in all types of diabetes. It was recently shown that increased proinsulin misfolding occurs well before the onset of diabetes and is responsible for events, including endoplasmic reticulum (ER) stress, leading to β-cell dysfunction and death in diabetes. There is currently no interventional means that suppresses proinsulin misfolding. In our preliminary studies, we identified a small molecule (named as PTTD) that protects β-cells from ER stress-induced death in a high- throughput screen. We discovered that PTTD suppressed the ER stress-induced activation of all three branches (IRE1, PERK, and ATF6) of unfolded protein response (UPR) pathways in β-cells under ER stress. We then observed that PTTD eliminated the accumulation of misfolded proinsulin while increasing mature insulin production in β-cells and that PTTD suppressed purified insulin protein misfolding/aggregation in cell- free biochemical assays. Importantly, in in vivo animal studies, PTTD significantly ameliorated hyperglycemia in multiple mouse diabetes models of β-cell failure. These exciting results demonstrate that suppression of proinsulin misfolding by PTTD protects β-cells and ameliorates diabetes. In this application, we will use PTTD as the starting molecule to develop potent analogs as first-in-class proinsulin misfolding inhibitors. To achieve this, we will use an approach that integrates iterative and parallel medicinal chemistry with in vitro and in vivo efficacy and DMPK studies with specific aims. In Aim 1, we will improve and optimize our lead compound, PTTD, through medicinal chemistry-based structure-activity relationship studies. In Aim 2, compounds with improved potency will be characterized physicochemically and pharmacologically using standardized ADMET and in vivo PK assays. In Aim 3, we will evaluate the in vivo efficacy of lead PTTD analogs in two well- established diabetes models of proinsulin misfolding and progressive β cell loss. Completion of this work will not only identify PTTD and its analogs as first-in-class chemical suppressors of proinsulin misfolding for β-cell protection, but also establish the suppression of proinsulin misfolding as a new therapeutic direction for diabetes, which will serve as a foundation and provide a lead compound that may guide further development of proinsulin folding therapeutics.

NIH Research Projects · FY 2025 · 2025-06

Parkinson’s disease (PD) and Dementia with Lewy Bodies (DLB) are progressive, incurable neurodegenerative disorders marked by pathological aggregation of alpha-synuclein (αsyn). Although extensive evidence indicates that αsyn aggregation causes neuronal dysfunction and loss, the detailed cellular mechanisms regulating αsyn toxicity are elusive. Understanding of homeostatic mechanisms that prevent αsyn aggregation in normal brains will inform the development of new disease-modifying therapies. One such promising target is 14-3-3θ. 14-3-3 proteins are highly expressed proteins that mediate neuronal function through protein-protein interactions (PPIs). The 14-3-3θ isoform is of particular importance in PD and DLB: 14-3-3θ overexpression reduces αsyn aggregation and toxicity, while 14-3-3θ inhibition exacerbates αsyn toxicity in αsyn models. We found an increase in phosphorylated 14-3-3θ at S232 in human PD and DLB, which correlated with cognitive decline. These data point to 14-3-3θ phosphorylation as a key contributor to αsyn pathology. Understanding the consequences of 14-3-3θ phosphorylation is critical to unlocking the potential of 14-3-3θ therapeutics. Molecular dynamics simulations reveal critical changes in the binding pocket upon S232 phosphorylation that are predicted to destabilize 14-3-3θ PPIs and thus disrupt its functions. Affinity-purified mass spectrometry from knock-in mice expressing the nonphosphorylatable S232A or the phosphomimetic S232D 14-3-3θ mutant showed reduced binding to several proteins critical to vesicular transport. In support of this, we found that retrograde axonal transport of acidic vesicles in S232D neurons is impaired. S232 phosphorylation also reduced αsyn binding and increased αsyn aggregation and toxicity in cellular αsyn models. Based on these data, we hypothesize that aberrant 14-3-3θ phosphorylation enhances vulnerability to αsyn by destabilizing critical PPIs. We predict 14-3-3θ phosphorylation 1) disrupts the 14-3-3θ/αsyn interaction needed to prevent αsyn aggregation, and 2) destabilizes 14-3-3θ/transport protein complexes needed to prevent αsyn accumulation. A promising therapeutic approach are stabilizers of 14-3-3 PPIs, several of which are currently in development as therapeutics for spinal cord injury. Fusicoccin-A (FC-A), a non-specific 14-3-3 PPI stabilizer, shows protection in αsyn models. In Aim 1, we will examine the structural interaction between 14-3- 3θ and αsyn, the impact of S232 phosphorylation on this PPI, and the impact of phosphorylation on αsyn aggregation and toxicity in vivo. In Aim 2, we will test the impact of S232 phosphorylation on axonal transport of AVs and lysosomes and targeting of αsyn into these vesicles. In both aims, we will use the non-specific PPI stabilizer FC-A as a tool compound to determine if augmentation of 14-3-3θ PPIs destabilized by 14-3-3θ phosphorylation can reduce αsyn pathology. Completion of the structural and functional studies in our proposal will enable discovery of clinically useful drugs to enhance 14-3-3θ PPIs for PD and DLB.

NIH Research Projects · FY 2026 · 2025-06

Project Summary This NIH F31 application is a request for support for Neda Ilieva, the Principal Investigator, to conduct research and career development activities that will equip her with the necessary skills to become an independent researcher. The project aims to investigate the key proteins, pathways, and mechanisms involved in environmentally-caused neurodegenerative diseases, particularly Parkinson’s disease (PD). The primary objective of this research proposal is to explore the role of lysosomal dysfunction and neuroinflammation in dopaminergic degeneration caused by exposure to trichloroethylene (TCE) in the context of PD. Previous work from the lab of Dr. Briana De Miranda, the PI’s sponsor, has shown that experimental exposure to TCE induces nigrostriatal dopaminergic neurodegeneration, motor deficits, endolysosomal dysfunction, neuroinflammation, and alpha-synuclein accumulation. In a feasibility study, we demonstrated that acute TCE inhalation induces lysosomal acidification deficits in a transgenic “Lysosensor” mouse. Furthermore, we showed that TCE exposure results in autophagy lysosomal pathway (ALP) deficits in vitro. We also found that the innate immune response protein, STING, is elevated in the midbrain tissue of animals exposed to TCE via inhalation. However, it is currently unknown whether these lysosomal deficits and neuroinflammation are in tandem with observed pathology or causal in nigrostriatal dopaminergic degeneration. This project aims to increase our understanding of the mechanisms by which lysosomal deficits induced by TCE contribute to neurodegeneration and neuroinflammation (Aim 1) and whether STING neuroinflammation is the driving factor for dopaminergic degeneration (Aim 2). The long-term objective of the PI’s research is to identify the role of environmental exposures in altering molecular pathways related to normal cellular function and to identify disease-modifying therapeutic strategies to stop the progression of the disease. The proposed training plan for Neda Ilieva is sponsored by Dr. Briana De Miranda and co-sponsored by Dr. David Standaert. The main objective of this plan is to equip Neda with the necessary conceptual and technical skills required to establish a strong foundation for a career in academic research. The plan has been developed with activities that focus on three crucial areas: 1) Conceptual and technical research, including studies in neurodegeneration, cognition, and neurotoxicology; 2) Statistical rigor, reproducibility, and transparency, including training in ethical research practices; and 3) Career development, including mentorship, teaching, and scientific communication. This proposal aims to uniquely prepare Neda to conduct rigorous hypothesis-driven research in neurotoxicology and neurodegenerative disease, while also developing the skills necessary to become a competent scientist, teacher, and mentor in academic science.

NIH Research Projects · FY 2026 · 2025-05

PROJECT SUMMARY Peripheral artery disease (PAD) is a severe form of cardiovascular disease (CVD) affecting > 230 million individuals worldwide. Given the compelling evidence that PAD is a consequence of diminished blood flow in one or more major arteries of the limb, the expectation has been to develop therapies designed to stimulate the formation of new mature blood vessels to restore blood perfusion. However, despite years of investigations, the advent of medical therapies designed to improve blood perfusion to the distal limb have proven to be of limited benefit, due in large part to a lack of understanding of the underlying molecular mechanisms involved in the formation of mature neovessels. Interestingly, while pursuing the goals of an alternate proposal aimed at determining the role of Leiomodin 1 (LMOD1), a CVD genome wide association study target gene preferentially expressed in smooth muscle cells (SMCs), in the pathogenesis of atherosclerosis, this investigator led team found that mice with reduced Lmod1 expression demonstrate increased plaque hemorrhage owing to rupture of the neovasculature within the plaque. While this study illustrates the potential role of Lmod1 in the formation of mature neovessels, there is a need to investigate this association in the context of PAD. Accordingly, through this proposal the investigators seek to elucidate the relationship between Lmod1 and PAD. Specifically, they will determine the contribution and mechanism by which this gene regulates the vascular biology of SMC dependent formation of mature neovessels, an attribute that may be critical in regulating the pathogenesis of PAD. This proposal will bring together recognized experts from several fields to complement the translational studies and unique mouse models proposed to thoroughly understand the role of LMOD1 in PAD. In Aim 1, we will use cell culture models as well as state-of-the-art genomic and human translational approaches to elucidate the mechanistic pathway by which reduced LMOD1 mediates impaired neovessel maturation. In Aim 2, we will determine whether the LMOD1 mediated defect in neovessel maturation and ultimately PAD is predominantly mediated through SMCs by performing advanced in vivo survival surgeries on newly generated and available inducible SMC specific Lmod1 knockout mice and importantly investigate whether the defect can be rescued. In Aim 3, using in vitro and in vivo approaches we will investigate whether LMOD1-mediated defects in neovessel maturation may also account for increased pathogenesis of PAD in type 2 diabetes mellitus (T2DM), a strong risk factor of PAD. Taken together, this work will enhance the scientific community’s understanding on LMOD1 mediated formation of mature neovessels, a critical regulator of PAD. The proposed work is relevant to the mission of the NIH as it will lead to the development of new strategies and potential therapies to effectively treat patients diagnosed with PAD.

NIH Research Projects · FY 2026 · 2025-05

PROJECT SUMMARY/ABSTRACT Cilia are complex and dynamic cellular structures crucial for normal development and tissue function. Genetic disruptions in ciliary proteins lead to a group of human diseases known as ciliopathies, which exhibit a broad spectrum of phenotypes including early gestational arrest, left-right body axis randomization, cystic kidney, liver, and pancreas abnormalities, hydrocephalus, neurological and cognitive disorders, blindness, anosmia, and obesity, etc. The manifestation and severity of ciliopathy disorders vary depending on the specific genetic mutation and its impact on ciliary function across different cell types and tissues. This variability has prompted the hypothesis that cilia exhibit distinct functions in various cell types, developmental stages, and environmental signaling contexts, as well as under pathological conditions and that this is dictated by alterations in the cilia proteome. Despite the clinical importance of cilia, there is a significant gap in our understanding of cilia functional roles and the signaling pathways they regulate in most cell types of the body. A key obstacle to advancing our knowledge of ciliary function is the lack of information on the ciliary proteome composition in different cell types and how it dynamically changes under varying conditions. This project aims to address this knowledge gap by developing a novel resource using the promiscuous ligase BirA*G3 fused with the transition zone protein B9d1 in mouse and cell-based models. The transition zone, located at the base of the cilium, serves as a crucial regulatory gate for controlling the entry and exit of proteins into and out of the cilium. The engineered cells and mouse lines will enable temporal and cell type-specific biotin labeling of proteins traversing the ciliary transition zone. Through the utilization of these innovative resources, we will assess the feasibility of this approach both in vivo and in vitro, with the goal of providing the research community with valuable tools to investigate the dynamics and diversity of the ciliary proteome. By enhancing our understanding of cilia function at the molecular level, this research has the potential to uncover novel insights into ciliopathy disorders and pave the way for the development of targeted therapeutic strategies.

NIH Research Projects · FY 2026 · 2025-05

PROJECT SUMMARY Out of control, or dysregulated, inflammation is a hallmark of numerous human diseases. Oxidized lipid mediators, oxylipins, are short-lived autacoids that play important roles in the etiology of inflammation. Quantification of urinary metabolites of prostaglandins and leukotrienes has been a key approach towards understanding of the role of these molecules – as well as the drugs used to inhibit them (ie. aspirin) – in human physiology and disease. Specialized pro-resolving lipid mediators (SPMs) are oxylipins typically generated from eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), that promote the resolution of inflammation. SPMs and their stable analogues are being developed as therapeutics to treat inflammatory-related diseases. But, while these molecules have been detected in certain biological settings, the extent to which SPMs are generated in vivo remains unclear. Importantly, there are distinct biological mechanisms – such as SPM metabolism and quantification of SPM metabolites – that have yet to be considered. Recently, our laboratory identified a novel route of SPM metabolism. We demonstrated that resolvin D5 (RvD5), one of the most abundant SPMs, is a substrate for uridine 5'-diphospho-glucuronosyltransferase (UGT) 1A9 and is rapidly metabolized via glucuronide conjugation. Limited studies on SPM metabolism exist; thus, we seek herein to gain a comprehensive understanding of SPM transformation. The central hypothesis of this proposal is that understanding the metabolism of SPMs is critical for the accurate and complete quantification of these bioactive lipids in human disease and homeostasis. We seek to address this hypothesis through three specific aims. In Specific Aim 1, we will identify and characterize routes pathways by which SPM are transformed using an in vitro model of human metabolism. We will study the metabolic inactivation of four structurally-distinct SPM – resolvin E4 (RvE4), resolvin D1 (RvD1), RvD5, and maresin 2 (MaR2). In Specific Aim 2, we will follow the metabolism of these SPMs in mouse models of human metabolism and inflammation. Additionally, we will utilize human plasma and urine samples previously collected as part of the Fatty Acid Desaturase Activity, Fish Oil, and Colorectal Cancer Prevention Study (FADAFO) to evaluate SPM metabolite formation in humans. Finally, in Specific Aim 3, we will address the concept that metabolism of SPM, particularly by UGTs, can be affected by commonly used medications, including non-steroidal anti-inflammatory drugs (NSAIDs). The effect of aspirin, ibuprofen, and other NSAIDs on the metabolism of SPMs will be explored in our proposed cellular and animal models. Together these aims present an innovative approach to detecting endogenous SPM formation. Identifying pathways that transform these molecules and establishing precise methods to ensure their accurate quantification will help to clarify mechanisms – and therapies – that regulate inflammation and outline a unique strategy to comprehensively evaluate SPM production for human clinical trials and epidemiological studies.

NIH Research Projects · FY 2026 · 2025-05

Project Summary: The use of amphetamine (AMPH) and its derivatives (e.g. methAMPH) has been linked to human immunodeficiency virus (HIV) transmission1, as HIV can spread through heightened unprotected sexual activity2, 3 that is associated with AMPH use disorder (AUD) 5, 6. For these and other reasons, AMPH dependence and HIV infection have been termed a double epidemic7. In this bidirectional relationship, the role played by AUD in synergizing HIV dependent neurodegeneration is well documented. For example, AUD exacerbates HIV impairments of central dopamine (DA) neurotransmission8-10. Furthermore, the HIV trans-activator of transcription regulatory protein Tat1-86 (Tat) and AMPH act in concert to impair striatal DA function11. Conversely, HIV and HIV proteins have been shown to enhance specific AMPH-induced behaviors. In rodents, expression of HIV proteins such as Tat, gp120, etc. enhance AMPH escalation12. Consistently, in humans, HIV infection increases AMPH frequency of use, frequency and duration of binging, as well as amount1, 13-17. This is important since the DSM-5 criteria for addiction includes a progressive intensification in drug use (i.e. escalation). To date, no examples exist of verified mechanisms or molecular descriptions of how HIV/HIV viral proteins alter AMPH molecular actions and/or behavioral expressions. This is the focus of this application. AMPH behavioral expressions (e.g. AUD) stem, at least in part, from their ability to reverse the function of the DA transporter (DAT), causing non-vesicular DA release, here defined as NVDR, resulting in an increase in extracellular DA levels4, 18. DAT is a plasma membrane protein that clears extracellular DA by its active transport into presynaptic terminals19. To gain a deeper understanding of NVDR, we provided the first evidence that specific domains of human DAT (hDAT) engage in direct association with the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2). These domains include the distal hDAT N-terminus (hDAT NT), and the hDAT intracellular loop 4 (IL4)4, 18, which contain basic residues that establish a network of electrostatic interactions with the anionic heads of PIP2. These interactions are essential for AMPH-induced hDAT NT phosphorylation, an event required for the interaction of hDAT NT with IL4 and for AMPH to promote NVDR and specific behaviors, including “sexual motivation”4, 18, 20. Tat is an unique HIV secreted protein, as it binds the anionic PIP2 with high affinity through its basic domains21-23. Consistent with Tat high affinity for PIP2, we demonstrated that Tat alters the electrostatic interaction of hDAT with PIP2 and, as a consequence, impairs NVDR. Of note is that escalation of drug intake is associated with blunted drug-evoked DA release, especially in psychostimulant use models24, 25. Thus, it is possible that Tat, by blunting AMPH-induced DA release (i.e. NVDR), promotes an increase in AMPH use1, 12-17. Here, by integrating a broad range of experimental approaches, we will test our mechanistic hypothesis that the molecular, functional and behavioral roles of Tat in AUD stem, at least in part, from their ability to regulate NVDR, a process dictated by its interactions with PIP2.

NIH Research Projects · FY 2026 · 2025-05

PROJECT SUMMARY Compared to men, women are twice as likely to be diagnosed with post-traumatic stress disorder (PTSD) and also experience higher rates of comorbidity with anxiety disorders and major depression. A common link between these psychiatric illnesses is dysregulation of valence processing that leads to exaggerated responses to negative stimuli, particularly to cues associated with trauma. The amygdala is well-established as the valence processing center of the brain. Converging evidence strongly implicates ovarian hormones in the regulation of both amygdala valence processing and PTSD symptom severity across the menstrual cycle, whereby high physiological levels of estradiol are beneficial. We and others have shown similar regulation of valence processing across the mouse reproductive cycle. When estradiol peaks during proestrus, negative valence behaviors decrease, whereas positive valence behaviors increase. While elegant research over the last decade has revealed populations of amygdala neurons that stably code stimuli conveying positive and negative valence, none of these studies investigated sex differences or hormonal regulation of these processes. The overall objective of this proposal is to bridge this critical gap in knowledge and discover novel cellular mechanisms within the amygdala that drive shifts in valence processing across the reproductive cycle. Based on preliminary data, we focus on local inhibitory connections called microcircuits that regulate activity of a unique principal neuron type that controls negative valence and is genetically defined by expression of R- spondin2 (Rspo2). We find that Rspo2 neurons and parvalbumin-containing inhibitory interneurons are enriched with estrogen receptor beta, which is known to regulate negative valence behavior and constrain amygdala plasticity. We show that both Rspo2 neurons and parvalbumin interneurons exhibit robust transcriptional plasticity across the reproductive cycle. Interestingly, our data suggest downregulation of parvalbumin interneuron neurotransmission in proestrus, leading us to hypothesize that these cells form a disynaptic circuit to inhibit Rspo2 neurons through disinhibition of other interneuron populations when estradiol levels peak. In Aim 1, we will interrogate estradiol-regulated sites of plasticity in this microcircuit with conventional and optogenetic-assisted slice electrophysiology. In Aim 2, we will establish the causal link between activity within this microcircuit and shifts in valence processing across the reproductive cycle with in vivo calcium imaging and closed-loop optogenetics. In Aim 3, we will determine the role of estradiol signaling in this microcircuit in the development of persistent negative valence following an intense acute stress model relevant to PTSD. Successful completion of these experiments will establish the existence and behavioral relevance of a novel inhibitory microcircuit for negative valence processing in the amygdala, as well as elucidate novel cellular mechanisms driving shifts in valence processing across the female reproductive cycle that may confer unique protection against stress experienced under high estradiol states.

NIH Research Projects · FY 2026 · 2025-05

PROJECT SUMMARY Substance use disorder is a complex neurobiological disease characterized by a loss of control over drug-taking and drug-seeking behaviors. Further exacerbated by the COVID-19 pandemic, the rate of drug-related overdoses and subsequent deaths has increased dramatically over the past decade, surpassing 107,000 in 2022. All drugs of abuse increase dopamine (DA) transmission within the nucleus accumbens (NAc) from DA projections from the ventral tegmental area (VTA). While the presence of tyrosine hydroxylase (Th) has long been used to identify DA neurons, more recent studies have revealed remarkable heterogeneity among VTA DA neurons, with some neurons co-expressing markers for both DA and glutamate (Glut) transmission that are similarly Th+. However, the role of DA-only compared to combinatorial cells in substance use disorder is currently unknown. Using single nucleus RNA sequencing to comprehensively profile the VTA, we previously identified unique markers for these two subpopulations of DA neurons. Slc26a7, a gene that encodes an anion transporter, serves as a selective marker for combinatorial neurons that harbor expression of genes implicated in both Glut and DA synthesis and neurotransmission. Likewise, the GTP cyclohydrolase Gch1 was identified as a marker for DA-only neurons. Using a fluorescent in situ hybridization protocol, I validated these findings showing the Slc26a7 marks DA+/Glut+ cells while Gch1 marks DA+/Glut- cells. I have shown unique induction of the neuronal activity marker Fos in Slc26a7+ cells in the VTA 1 hour following cocaine, but not fentanyl, experience; this same response was not observed in Gch1+ cells, suggesting a difference in response to cocaine between these two distinct DA neuron populations. These results suggest that two subpopulations of DAergic cells in the VTA respond to cocaine in unique ways and may in turn drive distinct downstream effects and behavioral responses to cocaine. Following these findings, I hypothesize that differences in cellular targets and neurophysiology confer distinct behavioral roles of DA subpopulations. Using these selective markers, I have designed and generated novel adeno-associated viruses (AAVs) to both express distinct fluorophores and manipulate the neurons in a cell-type specific way. Using these AAVs, this project aims to take a multidisciplinary approach to rigourously investigate and determine any differences in cell types through the following aims: (1) Characterize anatomical and cellular localization of projections, (2) Determine neurophysiological differences, and (3) Determine the role of combinatorial cells in behavior. The proposed studies will deepen our understanding of the role of these combinatorial cells in SUD, providing avenues for therapeutic exploration for a disease largely lacking treatment options. Under this award, I will master behavioral paradigms and electrophysiology, techniques that will aid my success as a physician-scientist.

NIH Research Projects · FY 2026 · 2025-05

PROJECT SUMMARY/ABSTRACT The Fc fragment of IgG binding protein (Fc gamma binding protein, FCGBP) is a prominent component of the mucus layer that lines the epithelium of the large intestine. Reduced levels of FCGBP are present in the structurally-weaken colon mucus layer that is characteristic of ulcerative colitis (UC). In addition, either low expression or deficiency due to genetically mutated FCGBP is associated with lower disease-free survival of patients with colorectal cancer (CRC). Normally, the abundance of FCGBP in the colon mucus layer is similar to that of mucin 2 (MUC2), the major secreted mucin in the colon. However, unlike MUC2, the functions of FCGBP are not well understood. In fact, a number of previously described functions of FCGBP, including the IgG interaction from which the name derives, have been subsequently disputed. We posit that the abundance of FCGBP in the barrier-protective colon mucus layer, coupled with the well-established association with diseases of the colon, warrant an improved and definitive understanding of the functions of this protein in health and disease. We have utilized mice with partial or complete loss of Fcgbp to begin to understand the functions of Fcgbp at homeostasis and during inflammation. Our studies suggest previously unknown but essential contributions to the structure of the colon mucus layer and to the composition of the mucus-associated microbiota. Fcgbp deficiency also appears to trigger major compensatory pathways, which potentially underlie the connection between low levels of FCGBP and susceptibility to colon inflammation and cancer. Therefore, in this exploratory proposal, we will determine the contribution of Fcgbp to the overall glycosylation and terminal sialylation of the colon mucus layer and determine how this affects the abundance of specific bacteria in the mucus layer. In addition, we will explore immune pathways that are deployed to limit spontaneous inflammation when expression of Fcgbp is suppressed and determine the possible connections to disease susceptibility. If successful, our studies will define novel functions for Fcgbp in intestinal immune homeostasis and identify key mechanisms whereby reduced Fcgbp impacts disease susceptibility in the large intestine.

NIH Research Projects · FY 2026 · 2025-05

Project Summary/Abstract Primary visual cortex (V1) is the key cortical area in the brain that establishes how visual perception operates in humans. Its central importance arises from two facts: V1 receives the majority of the signals generated by the retina and it establishes the dissemination of different types of visual information to higher cortical areas in the brain. Many previous studies have characterized the response properties of single V1 neurons, however all of them were conducted using the eye's natural optics, which are subject to optical aberrations. Such aberrations can lead to confounds between wavelength, orientation, and spatial frequency in visual stimuli, in particular at or near the fovea where these parameters are the most difficult to control. Using adaptive optics technology, we will overcome the limits imposed by optical aberrations in order to measure V1 neural responses at a cone-resolved level in the non-human primate for the first time. Several fundamental questions will be answered: (1) How many cone photoreceptors comprise a V1 neuron's receptive field near the fovea, and what cone types are they? (2) What is the elementary response of a V1 neuron to signals provided by a single cone? (3) How many V1 neurons receive input from a single cone? In the high spatial frequency domain needed to answer these questions near the fovea, we will be able to optically separate the parameters of wavelength and geometric orientation in order to also address a major unanswered question about how the visual signaling pathways in cortex are initially segregated: Do the populations of V1 neurons that project differentially to secondary visual cortex (V2) receive input from different cone compositions? These questions will be answered in tandem with a series of experiments that will additionally allow us to assess the impact of cone signal loss, as a model of what occurs in retinal degenerative diseases. By asking how resilient V1 responses may be in the face of synthetically degraded stimuli, we will learn if there is a V1-based mechanism behind why perceptual deficits in patients are often not as severe as retinal imaging of diseased tissue indicates. Our results will establish the basic signaling properties of cone photoreceptors as seen by V1 neurons and potentially reveal a cortical signature for perceptual “filling-in” at the single neuron level. Both of these outcomes will substantially improve our understanding of visual processing and create a new path for earlier detection of retinal disease. 1

NIH Research Projects · FY 2025 · 2025-05

Project Summary This project proposal is designed to elucidate the nature of immune-stem cell interactions that are inadvertently targeted by immunotherapies. Specifically, we focus on signaling between the immune checkpoint proteins programmed cell death 1 (PD-1) and programmed cell death ligand (PD-L1) as one mechanism by which immune cells and stem cells coordinate tissue immunity with tissue regeneration. We use melanocyte stem cells (McSCs) and hair repigmentation as the model. Our rationale for this proposal stems from our discoveries that 1) PD-L1 is expressed at the right time (during hair dormancy) and the right place (by quiescent McSCs in the hair follicle) to regulate both McSC immune privilege and quiescence; 2) blocking PD- L1 in this cell lineage increases cell cycling in vitro, and 3) blocking PD-L1 provides resistance to stress- associated hair graying in vivo. Further rational derives from the literature— PD-1/PD-L1 immune checkpoint inhibitor therapy for cancer causes two opposite pigmentation/immune-related adverse events (irAEs). On one hand we see vitiligo-like hypopigmentation in melanoma patients but on the other hand we see reversal of gray hair in non-melanoma patients. The objectives of our study are to decipher how PD-L1 enables crosstalk between McSCs and neighboring immune cells to regulate McSC immune privilege, maintain McSC quiescence, and balance the immunogenic and tolerogenic processes within the skin to enable pigment regeneration. To complete these objectives, we have assembled a team of experts in stem cells, pigmentation and hair biology, mouse transgenics, inflammatory disease models and immunology. With this combined expertise, we will investigate the regenerative capacity of McSCs in combination with adoptive transfer of Jedi T cells, anti- PD-1 and anti-PD-L1 antibodies that mimic human immunotherapies, and in the context of a novel mouse model of post-inflammatory skin hypopigmentation. We will also employ McSC lineage tracing and our novel in vitro quiescence assay to further interrogate PD-L1 function in cell cycling. The results of these studies are the foundation to addressing a critical question in the field of immunotherapy. How do we do we tip the balance towards immunotherapy’s undeniable benefits and away from its irAEs? The diversity of irAEs, the organs they affect, and their onset and severity suggest immunotherapy has numerous targets that do not all represent the same basic pathology. Thus, revealing the underlying biology behind individual immune-related toxicities is key to harnessing the full potential of immunotherapy treatment. This study will also provide insight into the immune-stem cell dialog enabled by PD-1/PD-L1 signaling. More broadly, this study contributes to the growing paradigm that immune cells and stem cells mutually regulate one another’s behavior to orchestrate regenerative tissue homeostasis and repair in the context of tissue immunity.

NIH Research Projects · FY 2025 · 2025-05

PROJECT SUMMARY Compared to men, women are twice as likely to be diagnosed with post-traumatic stress disorder (PTSD) and also experience higher rates of comorbidity with anxiety disorders and major depression. A common link between these psychiatric illnesses is dysregulation of valence processing that leads to exaggerated responses to negative stimuli, particularly to cues associated with trauma. The amygdala is well-established as the valence processing center of the brain. Converging evidence strongly implicates ovarian hormones in the regulation of both amygdala valence processing and PTSD symptom severity across the menstrual cycle, whereby high physiological levels of estradiol are beneficial. We and others have shown similar regulation of valence processing across the mouse reproductive cycle. When estradiol peaks during proestrus, negative valence behaviors decrease, whereas positive valence behaviors increase. While elegant research over the last decade has revealed populations of amygdala neurons that stably code stimuli conveying positive and negative valence, none of these studies investigated sex differences or hormonal regulation of these processes. The overall objective of this proposal is to bridge this critical gap in knowledge and discover novel cellular mechanisms within the amygdala that drive shifts in valence processing across the reproductive cycle. Based on preliminary data, we focus on local inhibitory connections called microcircuits that regulate activity of a unique principal neuron type that controls negative valence and is genetically defined by expression of R- spondin2 (Rspo2). We find that Rspo2 neurons and parvalbumin-containing inhibitory interneurons are enriched with estrogen receptor beta, which is known to regulate negative valence behavior and constrain amygdala plasticity. We show that both Rspo2 neurons and parvalbumin interneurons exhibit robust transcriptional plasticity across the reproductive cycle. Interestingly, our data suggest downregulation of parvalbumin interneuron neurotransmission in proestrus, leading us to hypothesize that these cells form a disynaptic circuit to inhibit Rspo2 neurons through disinhibition of other interneuron populations when estradiol levels peak. In Aim 1, we will interrogate estradiol-regulated sites of plasticity in this microcircuit with conventional and optogenetic-assisted slice electrophysiology. In Aim 2, we will establish the causal link between activity within this microcircuit and shifts in valence processing across the reproductive cycle with in vivo calcium imaging and closed-loop optogenetics. In Aim 3, we will determine the role of estradiol signaling in this microcircuit in the development of persistent negative valence following an intense acute stress model relevant to PTSD. Successful completion of these experiments will establish the existence and behavioral relevance of a novel inhibitory microcircuit for negative valence processing in the amygdala, as well as elucidate novel cellular mechanisms driving shifts in valence processing across the female reproductive cycle that may confer unique protection against stress experienced under high estradiol states.

NIH Research Projects · FY 2026 · 2025-04

Project summary Substance use disorder (SUD) is a debilitating disorder characterized by severe alterations in the neural circuits of reward. Among others, the gamma aminobutyric acid (GABA) system is a critical component of the pathology of SUDs. While historically studied in the context of alcohol use, the GABAergic system is now gaining more attention for its roles in mediating the rewarding properties of other drug types (such as opioids) and natural rewards. However, in comparison to other systems like dopamine, our understanding of the GABAergic mecha- nisms of reward seeking is far less complete. Like the fields of reward and addiction, a vast majority of studies of fear memory, which is where our previous work was situated, generally cast GABAergic neurons aside as simple gain modulators and instead focus on glutamatergic neurons as the main memory substrate. As a result, much less is known about whether and how GABAergic neurons themselves encode aversive memory. We pioneered this area and revealed that a population of somatostatin-expressing interneurons (SST-INs) in the prelimbic (PL) region of the rodent medial prefrontal cortex is a prominent substrate of fear memory. We also identified a second orthogonal PL SST-IN population which is activated by a single intraperitoneal morphine injection that drives positive valence. While these results hint towards a role for PL SST-INs in reward, the mech- anisms that underlie this function are unknown. Moreover, how PL SST-INs may differentially regulate different reward behaviors, such as natural and drug reward seeking, is unstudied. We will address these gaps by pursu- ing three Aims. 1. Reveal the in vivo dynamics, behavioral contributions, and map the circuits of PL SST-INs that drive natural and drug reward seeking. We will perform Miniscope imaging of PL SST-INs across natural and drug reward seeking to reveal when and how they are activated in self-administration tasks. Next, we will perform intersectional activity-dependent neural tagging and in vivo optogenetics to determine the specific contributions of tagged neurons to natural and drug reward seeking behaviors. Last, we will use nested optogenetics-based neural tagging to reveal the organization and brain-wide projections of PL projection neurons disinhibited by natural and drug reward-tagged SST-INs. 2. Determine the circuit plasticity mechanisms of operant natural and drug reward seeking in PL SST-INs. By using intersectional activity-dependent neural tagging and optogenetics- assisted brain slice physiology, we will reveal the synaptic and intrinsic plasticity mechanisms as well as the specific microcircuit alterations related to natural and drug reward seeking in SST-INs. 3. Reveal the transcrip- tional profiles of PL SST-INs driving operant natural and drug reward seeking. We will isolate nuclei from PL SST-INs tagged in response to natural and drug reward seeking and subject them to single-nucleus RNA-seq. Comparisons will be made between natural and drug reward-tagged as well as non-tagged PL SST-INs to reveal reward-specific transcriptional programs. Overall, results from this work will provide important fundamental in- sight to the mechanisms of natural and drug reward seeking in PL SST-INs.

NIH Research Projects · FY 2026 · 2025-04

PROJECT SUMMARY Opioid use disorder (OUD) can be conceptualized as a two-sided coin, with one side of the pathology characterized by excessive motivational drive for opioids, and on the other side, a weakened ability to suppress opioid-seeking impulses. As the seat of executive function, the prefrontal cortex plays an integral role in the decision ‘to seek or not to seek’ opioids. We have identified two functionally opposing prefrontal subcircuits that drive versus limit opioid seeking. The infralimbic (IL) prefrontal cortex projection to the lateral hypothalamus (ILàLH) drives heroin seeking, whereas the IL projection to the nucleus accumbens shell (ILàNAshell) limits it. We also discovered that these distinct IL ensembles encode heroin cue-learning, a process that contributes to subsequent relapse triggered by heroin cues encountered in the environment. Relapse is an important metric of OUD pathology, but our data suggest that heroin choice, the tendency to choose heroin reward over non-drug reward, is a separate metric of OUD pathology that does not always respond to treatments aimed at reducing relapse. Thus, we will employ a preclinical model of OUD that captures multiple metrics of OUD pathology, including heroin choice and relapse. Furthermore, the downstream target of the IL driver includes LH orexin neurons, which we hypothesize are a biomarker of OUD pathology, as current evidence suggests the number of these neurons increases after repeated opioid exposure and this number positively correlates with heroin motivation. Our preliminary data indicate that the ILàLH driver subcircuit is more responsive to orexin than the ILàNAshell limiter subcircuit, posing the possibility that a positive feedback loop in the ILàLH driver subcircuit is engaged to perpetuate opioid seeking. Importantly, orexin antagonists have been a major focus in the search for new OUD medications, and this newly identified driver circuit could be a major mechanism through which orexin drives opioid seeking. The goals of this proposal are to determine whether the recruitment of the IL driver circuit is a hallmark of heroin-induced pathology, whether this IL subcircuit engages a positive feedback loop via the orexin system to further exacerbate heroin seeking, and whether simultaneously targeting both IL subcircuits to normalize IL output can be used to reverse this pathology. The discovery of distinct IL driver and limiter circuits that control heroin seeking is highly significant because it points to novel interventions aimed at shifting the balance between these circuits as potential anti-addiction treatment strategies. We will also identify how the orexin system interacts with this circuitry and whether this may be another potential point of intervention. The information gained from these experiments could have profound implications for OUD treatment by identifying multiple ways to restore adaptive functionality in these prefrontal circuits and ameliorate OUD pathology, either by reducing excessive motivational drive for opioids or by strengthening inhibitory control over impulses to seek opioids, or both.

NSF Awards · FY 2025 · 2025-04

NON-TECHNICAL SUMMARY: The University of Alabama at Birmingham (UAB) in partnership with Historically Black Colleges and Universities (HBCUs) in Alabama will host a Research Experiences for Undergraduates (REU)-site in experimental and computational materials research. This project offers a broad range of interdisciplinary materials research experiences to undergraduate students enrolled in physics, chemistry, applied mathematics, and engineering. The undergraduate students will gain experience in materials synthesis, materials characterization, computer modeling and simulations, and in conducting research at national laboratories. This project will provide lecture series and workshops in materials growth and characterization, research ethics and professionalism, innovation and entrepreneurship, and applying for advanced degrees in the science and engineering fields. This REU-site plans to develop a pipeline of undergraduate researchers who will become leaders in advances in science and discovery of novel materials and contribute to economic development and become part of a trained workforce in national defense. TECHNICAL SUMMARY: The REU-research projects are organized in four research clusters: (1) materials under extreme conditions (2) machine learning and simulations in materials research, (3) infrared lasers and spectroscopy, and (4) 3-D printed biomaterials and drug delivery platforms. The undergraduate research projects will contribute to fundamental understanding of phase transformations and behavior of materials under extreme conditions, machine learning enabled materials discovery, materials for mid-IR lasers and quantum information systems, and 3-D printed biomaterials and stimuli responsive polymers. The undergraduate research projects make extensive use of synchrotron x-ray source and spallation neutron source available at national laboratories in the United States The undergraduate student projects have short-term achievable milestones, while simultaneously contributing to longer-term scientific goals and technological applications. Our teaming arrangement of REU-participants with faculty and graduate students, giving poster and oral presentations, writing a research-style paper, and attending training seminars in scientific communications and ethics will help REU students see the big picture of what it takes to develop into a research scientist with the critical skills needed for analyzing, interpreting, and presenting scientific data. After conclusion of the ten-weeks summer research project, the program offers continual support to REU-participants in disseminating research results at professional meetings and in peer-reviewed publications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2025-04

ABSTRACT The goal of this investigation is to characterize the influence of macro-level exposures on associations of mutational signatures and T-cell immunity in high-risk monoclonal gammopathy of undetermined significance (MGUS). MGUS is a necessary precursor to multiple myeloma (MM) suggesting that driver events accumulated at the early precursor stage provide an evolutionary trajectory that predisposes to late-stage disease. Despite the importance of MGUS, our current understanding of its etiology is almost exclusively inferred from MM resulting in a knowledge gap of events driving the transition from early to late-stage disease. By directly evaluating MGUS, we will improve our understanding of the macro-level exposures and genomic mechanisms that drive risk. In this proposed investigation, we will test the overarching hypothesis that distinct mutational signatures and T-cell immunity are associated with the presence of MGUS and that macro-level exposures modify the effect of these factors that drive the risk of MGUS. Our objective to model the influence of macro- and micro- level factors relative to early genomic events underlying the evolutionary trajectory of MGUS is a critical step toward characterizing the biology that drives high-risk MGUS and may provide a clinically impactful tool for early detection, clinical monitoring and advancing interception strategies. The specific aims are to: (1) determine the influence of macro-level exposures on the risk of MGUS-MM, (2) identify mutographs and T-cell immune responses associated with MGUS risk, and (3) determine the extent to which macro-level exposures modify the effect of mutographs and T-cell immunity on the risk of MGUS. The proposal is highly innovative, timely and leverages existing resources and comprehensive, high-quality data together with biospecimens systematically collected in well-characterized populations to advance our understanding of MGUS etiology, and a biological basis for high-risk MGUS. Anticipated findings will uncover modifiable risk factors, identify populations at risk for MGUS-MM, and may provide a foundation to discover novel therapeutic targets and effective interception strategies to improve the health of all populations at risk for MGUS-MM.

NIH Research Projects · FY 2026 · 2025-04

PROJECT SUMMARY Small cell lung cancer (SCLC) is a highly aggressive form of lung cancer with a dismal survival rate. The response of SCLC to current therapies is short-lived and the disease progression is inevitable in most patients. Furthermore, unlike other lung cancer types, there is a notable scarcity of targeted therapies in SCLC. The bispecific T-cell engager (BiTE) antibodies represent a transformative new approach in cancer therapy that facilitates T-cell-mediated eradication of cancer cells. Due to their effectiveness the U.S. FDA has approved several BiTE antibodies for treating various cancers. Delta-like ligand 3 (DLL3) is overexpressed in most SCLCs, which prompted the development of a novel BiTE antibody, Tarlatamab. Tarlatamab specifically targets DLL3 on SCLC cells and CD3 on T-cells, leading to T-cell mediated tumor lysis. In the recent Phase II clinical trial DeLLphi-301, Tarlatamab demonstrated potent anti-tumor activity, achieving durable objective responses in 40% of previously treated SCLC patients and showing encouraging survival outcomes. The Phase III clinical trial (ClinicalTrial.Gov ID# NCT05740566) is underway and its clinical approval in the third-line (3L) setting for SCLC is expected to occur this year. However, the median progression-free survival benefit with Tarlatamab is limited to approximately 4.9 months, highlighting the need to identify molecular drivers of response, which will allow more effective use of Tarlatamab in SCLC patients. We performed a CRISPR-based gene activation (CRISPR- a) screen by activating the expression of over 350 human genes encoding epigenetic regulators. This screen and subsequent analyses identified EZH2 overexpression as a key event that drives Tarlatamab resistance in SCLC. Our overall objective is to determine the in vivo role of EZH2 in conferring resistance to Tarlatamab in SCLC and evaluate pharmacological inhibition of EZH2 for enhancing the efficacy of Tarlatamab in SCLC. In Aim 1 studies, we will model the in vivo impact of genetic and pharmacological inhibition of EZH2 in forestalling and reversing the resistance to Tarlatamab in SCLC. To test this, we will use human SCLC cells and T-cell admixture mouse model and a novel immunocompetent humanized mouse model with a human immune system. To pharmacologically inhibit EZH2, we will use a U.S. FDA approved EZH2 inhibitor Tazemetostat, and test if treatment of SCLC cells with Tazemetostat can forestall and/or reverse the resistance to Tarlatamab in SCLC. In Aim 2 studies, we will elucidate the role of canonical and non-canonical functions of EZH2 in driving resistance to Tarlatamab in SCLC. First, we will determine the role of EZH2-mediated transcriptional repression of DLL3 and other DLL3-independent mechanisms in conferring resistance to Tarlatamab. Next, we will utilize the EZH2 degrader, MS1943, and a catalytically inactive mutant of EZH2 to probe the non-canonical functions of EZH2 in determining resistance to Tarlatamab in SCLC. Collectively, these studies will identify a novel therapeutically targetable pathway to enhance the efficacy of Tarlatamab in SCLC.

NSF Awards · FY 2025 · 2025-04

This project aims to uncover the intricate ways neurons communicate and how this communication influences brain development and maturation. The goal of this investigation is to discover how chemical signals between neurons, such as neurotransmitters and neuropeptides, contribute to the growth and function of the nervous system. By studying the nervous system of a simple and well-understood model organism, like the worm Caenorhabditis elegans, this study will contribute with insights that could benefit a wide range of species, including humans. This research could lead to a better understanding of brain health and disease, and the findings could have broad implications for improving educational and outreach programs. Additionally, the project will foster the development of future scientists, by providing hands-on research experiences and enhancing communication skills. This proposal seeks to investigate the role of neuron-neuron communication, particularly through neurotransmitter-based and neuropeptidergic chemical neurotransmission, in the post-mitotic maturation of neurons during postnatal development. Utilizing the model organism Caenorhabditis elegans, this investigation will leverage advanced genetics, behavioral assays, microscopy, and genomics tools to examine the molecular and functional maturation of neurons. The research will address key questions about the impact of various modes of neurotransmission on behavior, synaptic connectivity, and gene expression. By systematically manipulating neuronal transmission in a temporally and spatially specific manner, this project aims to delineate the interplay between extrinsic environmental stimuli and intrinsic genetic timer mechanisms in regulating neuronal maturation. This study will provide critical insights into the mechanisms of neuronal development, with potential implications for understanding brain function and disease across species. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NSF Awards · FY 2025 · 2025-03

This project will study the spread of the genes that make bacteria resistant to antibiotics, and how that spread is affected by heavy metal pollution. One of the greatest threats facing human society in the coming decades is an increase in antimicrobial resistant bacteria. The widespread use of antibiotics starting in the mid-20th century led to plummeting rates of mortality from infections and contributed to one of the greatest increases in life expectancy of any technological innovation. Unfortunately more and more infections that resist antibiotic treatment are occurring, threatening to undo those advances and usher in a much more dangerous post-antibiotic era. The overuse of antibiotics by doctors and hospitals is often cited as the cause of this change, but research suggests that environmental pollution might also play a role. In a historically contaminated part of Birmingham, Alabama, that has housed coal-burning facilities for over a century, elevated levels of heavy metals like lead and manganese appear to favor the evolution of bacteria that are resistant not only to these toxic substance but also to antibiotics. The predominantly African American residents of the affected neighborhoods already face elevated levels of respiratory and other chronic diseases, and they may also face elevated risk of dangerous antibiotic resistant infection due to the heavy metals in their environment. This research will put a scientific lens on the question of where antibiotic resistance comes from and how it spreads from point sources into the environment, but it will also confront the environmental injustice experienced by the human beings who are bearing the costs of decades of industrial pollution. The project will involve the people who live in the affected neighborhoods, where the researchers will attempt to win back some of the trust in science that has been lost due to a history of neglect and corruption surrounding this neighborhood and its ongoing struggle with the residue of its industrial past. It is generally accepted that antibiotic resistance spreads fastest in bacteria through horizontal gene transfer. This research will attempt to observe these exchanges taking place using a unique laboratory method, where an environmental sample is separated from laboratory bacteria by a membrane that has pores big enough to allow DNA, but not cells, to pass, and then to see what kinds of antibiotic resistance genes from the environment are able to be transferred into the lab strains. Researchers will also collect soil and wastewater from around the Birmingham area to see how much antibiotic resistance exists in the environment, and mathematicians will use computer models to understand whether the resistance genes are coming from humans using antibiotics as medicine, from agricultural sources, from pollution in the soil, or from a combination of these factors. Despite the critical importance of horizontal gene transfer in this and other bacterial activities, very little is known about how it actually takes place in nature, how fast it can move genes around, or how far from a point source it can move resistance genes; this research will address all of these topics using cutting-edge laboratory and computational tools. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

NIH Research Projects · FY 2026 · 2025-03

PROJECT SUMMARY/ABSTRACT Bacterial diseases of the oral cavity (e.g. caries) are fundamentally polymicrobial, and understanding the inter- action between different species of bacteria is central to understanding how the oral microbiota is modulated. Among the most abundant bacteria in human saliva are Streptococcus species, some of which are dominant in healthy individuals and some of which are associated with or more abundant during diseased states. Hypothio- cyanous acid (HOSCN) is an antimicrobial oxidant abundant in saliva that is synthesized by mammalian heme peroxidases from H2O2 and thiocyanate (SCN-). Saliva contains the highest concentrations of SCN- in the human body (up to 3 mM), and the antimicrobial activity of the HOSCN produced by salivary lactoperoxidase (LPO) has been known for over 60 years. Early biochemical experiments showed that that commensal, health-associated oral streptococci (e.g. Streptococcus sanguinis) possess an enzymatic activity capable of degrading host-derived antimicrobial oxidants, while the caries-associated pathobiont S. mutans does not. We have recently identified a broadly-distributed bacterial HOSCN reductase (called RclA) that protects bacteria against the antimicrobial effects of HOSCN. S. sanguinis encodes an RclA homolog, while S. mutans does not. This now presents us with the opportunity to directly test the long-standing hypothesis that HOSCN reductase activity is important in the competition between health- and disease-associated oral streptococci. Doing so, how- ever, will also enable us to undertake a more careful examination and dissection of the role of LPO in modulating the oral microbiota and its potential use as an antimicrobial to modulate early dental plaque biofilm development. AIM 1. Identifying and characterizing HOSCN responses in oral streptococci Using genetically-tractable strains of S. sanguinis and S. mutans and a newly optimized defined artificial saliva medium, we will use molecular genetic, biochemical, and transcriptomic approaches to identify and test the impact of individual genes (e.g. rclA in S. sanguinis) and pathways that contribute to the ability of oral streptococci to respond to HOSCN. We will test the impact of these genes on the growth of HOSCN- stressed single and dual-species cultures both planktonically and in surface-associated biofilms. AIM 2. Characterizing the impact of LPO and its products on interactions between oral streptococci The extent to which LPO’s impact on oral bacteria is HOSCN-dependent under physiological conditions is unclear. We will characterize the impact of physiological concentrations of pro- and anti-oxidant products found in saliva on interactions between S. sanguinis and S. mutans in artificial saliva, both during planktonic growth and in surface-associated biofilms. The results of this work will be the first molecular-level understanding of how the pro- and anti-oxidant compo- nents of saliva drive growth and competition between cariogenic and non-cariogenic oral Streptococcus species.

NIH Research Projects · FY 2026 · 2025-03

PROJECT SUMMARY: Cardiovascular diseases are leading cause of morbidity and mortality in the US. Cardiac fibrosis is a fundamental mediator of heart failure progression. Following myocardial stress, fibroblasts are activated, resulting in extracellular matrix deposition in the heart's different regions and leading to cardiac fibrosis and subsequent cardiac dysfunction. Thus, understanding the molecular mechanisms underlying cardiac fibrosis is crucial for developing effective therapies. Several signaling cascades have been identified as key regulators of fibrosis. Among these, b-catenin-mediated activation of profibrotic genes expression is crucial in the progress of cardiac fibrosis. However, the precise mechanism that regulates b-catenin nuclear translocation (a key step for b-catenin-mediated fibrosis) during cardiac injury remains incompletely understood. The premise of this proposal is based on the strong preliminary data that confirm the contribution of RAPGEF5 (a guanine nucleotide exchange factor) mRNA methylation in the regulation of β-catenin nuclear translocation and its impact on the progress of cardiac fibrosis. RNA modifications, specifically methylation, are known to be important in regulating mRNA stability, splicing, and translation, but their role in cardiac fibrosis is not well studied. The central hypothesis of this application is that activation of METTL3 by TAC (pressure overload) leads to increased stability of RAPGEF5 mRNA, which promotes β-catenin translocation into the nucleus, resulting in the activation of fibrotic genes and progress of cardiac fibrosis. We hypothesize that inhibiting or deleting METTL3 will mitigate adverse cardiac remodeling by reducing fibrosis. In Aim 1, we will investigate the direct link between METTL3 activation and cardiac fibrosis progression using a fibroblast-specific METTL3 transgenic mouse model subjected to pressure overload-induced heart failure. In Aim 2, we will elucidate the mechanisms by which METTL3 regulates RAPGEF5 mRNA stability and β- catenin-mediated fibrotic signaling. This will involve overexpressing METTL3 in fibroblasts both in vivo and in vitro, followed by examination of RAPGEF5 and β-catenin expression, stability, and fibrotic signaling. Finally, in Aim 3, we will explore the therapeutic potential of inhibiting METTL3 in a mouse model of pressure overload-induced heart failure. We will treat mice with a pharmacological inhibitor of METTL3 (STM2457), either before the onset of heart failure (prevention strategy) or two weeks after (treatment strategy), and then assess various biochemical parameters as described in Aims 1 and 2.