University Of California Los Angeles

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY Cannabis use is becoming increasingly common in the US, and past-month use among pregnant women increased by almost 60% from 2003 to 2019. Despite increasingly permissive legislation, our knowledge of the behavioral and neurobiological consequences of prenatal exposure to cannabis and delta-9- tetrahydrocannabinol (THC) lags behind. Hazardous cannabis use has been linked to psychosis onset and psychotic-like experiences throughout the lifespan, and both cannabis use and psychosis have overlapping neural foundations in reward circuitry. However, the effects of prenatal cannabis exposure on youth psychopathology are not yet known. Reward pathways implicated in cannabis use disorder and psychosis offer key insights into how prenatal cannabis exposure may shape psychosis outcomes; functional brain alterations during reward anticipation may represent a biomarker of disrupted reward processing. To enable the development of early interventions and the discovery of robust biomarkers of psychosis risk, it is imperative to determine relationships between neural and behavioral indices associated with hazardous cannabis use and psychosis across development and inform predictive models. A unique opportunity to advance this work is provided by the Adolescent Brain Cognitive Development (ABCD) Study, a 10-year national collaboration of 21 research sites designed to study the effects of substance use across development. The cohort includes 655 youth ages 9-13 who were exposed to cannabis prenatally and 10,834 who were not. Specially, the project aims are to: 1) characterize longitudinal associations between prenatal cannabis exposure and psychotic-like experiences (PLEs) across two years of follow-up; and 2a) Predict PLEs via machine learning classifiers built on baseline psychosocial and environmental psychosis risk factors, including prenatal cannabis exposure, and 2b) Predict PLEs via machine learning classifiers built on multivariate pattern analysis of neural activity in reward- related brain regions during reward anticipation in a monetary incentive delay fMRI task. The results of the study will have immediate public health and clinical implications providing clinicians, patients, and policymakers with critical data on the impacts of prenatal cannabis exposure on youth mental health outcomes. Additionally, results will aid in development of models for predicting psychosis risk during child development and inform future studies on effects of in utero cannabis exposure. Completion of the training plan proposed here will provide essential training in longitudinal modeling, neuroimaging approaches including task-based functional MRI (fMRI) and machine learning techniques crucial to completing these aims. The Bearden and Cooper Labs and the Neuroscience Interdepartmental Program at the University of California, Los Angeles will provide the ideal training environments for the successful completion of this proposal.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY/ABSTRACT The World Health Organization (WHO) classification of gliomas has been steadily shifting from a histological classification towards a molecular classification. For example, isocitrate dehydrogenase (IDH) mutational status is a critical feature of the recent 2021 WHO classification. Compared to IDH-wild-type (IDH-wt) gliomas, IDH- mutant (IDH-m) gliomas have distinct clinical characteristics such as accounting for most low-grade gliomas (LGGs; grade 2), having better prognosis, growing slower, and affecting a younger patient population compared to IDH-wt gliomas. However, all WHO grade 2 IDHm gliomas are expected to eventually become malignant higher-grade (WHO grades 3-4) gliomas in a process known as malignant transformation. Upon malignant transformation, patients with IDHm gliomas have a significantly worse prognosis. Thus, early, non-invasive imaging biomarkers of IDHm glioma malignant transformation may allow for earlier identification of treatment failure and appropriate therapeutic interventions. Magnetic resonance imaging (MRI) is critical for the management of patients with IDHm gliomas. Currently, identification of malignant transformation in patients with IDHm gliomas involves the emergence of contrast- enhancing areas on T1-post-contrast MRI in previously non-enhancing grade 2 gliomas. However, advanced MRI biomarkers sensitive to acidity, perfusion, and cellular density may provide earlier identification of the tumor microenvironment changes associated with malignant transformation and earlier identification of treatment failure. Furthermore, combining our lab’s pH-sensitive MRI with metabolic positron emission tomography (PET) imaging may yield deeper insights into the tumor microenvironment, particularly for metabolic shifts associated with malignant transformation and new IDH inhibitor targeted therapies that inhibit the mutant IDH enzyme. As a result, this proposal seeks to identify molecular MR-PET biomarkers associated with malignant transformation and successful IDH inhibition of IDHm gliomas. In Specific Aim 1, we will establish a sequential order of advanced MRI biomarkers in IDHm gliomas undergoing malignant transformation using pH-sensitive, perfusion, diffusion, and anatomical MRI and then validate MR-PET biomarkers of IDHm gliomas with histopathological markers from targeted surgical biopsies. In Specific Aim 2, we will utilize pH-sensitive MRI and PET to evaluate metabolic perturbations in IDHm gliomas following successful IDH inhibitor therapy. The proposed studies may improve IDHm glioma management by establishing imaging biomarkers of malignant transformation and successful IDH inhibitor treatment response.

NIH Research Projects · FY 2025 · 2023-09

We propose to conduct a prospective cohort (observational) study of 150 participants with moderate to severe obstructive sleep apnea (OSA) unable to tolerate positive airway pressure who are undergoing drug-induced sleep endoscopy (DISE), including measurement of upper airway closing pressure (Pclose), and tissue-repositioning soft palate surgery. Before and 6 months after surgery, we will measure OSA severity (apnea-hypopnea index) with sleep studies (polysomnograms). Using our recently-validated polysomnography-based signal processing algorithm, we will systematically assess the underlying mechanisms of OSA (traits) and airflow shape (consistent with palate obstruction). The expected 90 participants without resolution of OSA after surgery (surgery failures) will participate in an experimental randomized crossover study of acetazolamide (1 month) and acetazolamide/eszopiclone combination (1 month). Polysomnograms will be performed with each treatment, with algorithm-based determination of traits. The research goals are: (1) to define how mechanistic traits modify effectiveness of anatomic treatment (surgery) and (2) to examine the therapeutic efficacy of surgery in combination with endotype-directed (especially loop gain- and arousal threshold-directed) treatment. Aim 1: To determine the mechanistic factors modifying the impact of soft palate surgery on airway collapsibility. Hypothesis: tissue-repositioning palate surgery will decrease airway collapsibility, with the decrease greater with palate-only obstruction (based on DISE and non-invasive airflow shape analysis). Aim 2: To evaluate the mechanistic factors modifying efficacy of soft palate surgery on OSA severity. Hypotheses: surgery efficacy will be independently associated with palate-only obstruction (DISE) and the following prior to surgery: lesser airway collapsibility, lesser loop gain, and greater arousal threshold. Aim 3: To evaluate the efficacy of combining surgery with loop gain and arousal threshold interventions. Hypotheses: In surgery failures (non-responders), lowering loop gain (acetazolamide) will lower OSA severity (expected response rate = 40%); efficacy will be associated with lesser postoperative (prior to medication) airway collapsibility and greater postoperative loop gain. Lowering loop gain and raising arousal threshold together (acetazolamide/eszopiclone) will further reduce OSA severity (expected response rate = 60%); efficacy will be associated with lesser postoperative airway collapsibility and the combination of greater postoperative loop gain and lesser postoperative arousal threshold.

NIH Research Projects · FY 2024 · 2023-09

PROJECT SUMMARY In neurodevelopmental disorders such as schizophrenia (SCZ), genetic and environmental factors converge on disrupted brain development and function. One way that we can gain more clarity on the relationships between genes, neural systems, and symptoms is through considering rare genetic conditions with large effects on brain development. 22q11.2 Deletion Syndrome (22qDel) is a recurrent copy number variant (CNV) in which a hemizygous deletion of ~2.6 Mb of genetic material (~46 protein-coding genes) from chromosome 22 causes a neurodevelopmental phenotype with a ~25% risk of psychotic illness and increased rates of ASD, intellectual disability, attention deficit and anxiety disorders. Studying individuals with 22qDel can therefore provide an impactful translational model and ‘genetics-first’ framework for understanding the complex biological pathways underlying disabling conditions like SCZ. The proposed research plan seeks to map convergent and divergent brain connectivity disruptions in 22qDel and in individuals at Clinical High Risk (CHR) for developing psychosis spectrum disorders relative to typically developing (TD) controls. To this end, we will make use of the largest multi-site sample collected to date of longitudinal resting-state fMRI from 22qDel (n=217) and matched controls (n=149), along with data from the North American Prodrome Longitudinal Study (NAPLS) with CHR (n=318) and TD (n=206). We will also apply spatial transcriptomic data from the Allen Human Brain Atlas (AHBA) to test relationships between fMRI biomarkers and typical spatial patterns of gene expression in the brain. Specifically, our aims are to: (i) Test the hypothesis that functional connectivity disruptions in individuals with genetic and clinical risk factors for psychosis converge on brain-wide sensory and executive networks, (ii) Test the hypothesis that 22qDel and CHR will exhibit convergent disruptions in functional connectivity development across the age range relative to TD controls, and that individual deviations from typical trajectories will predict psychosis symptoms, and (iii) Test the hypothesis that spatial patterns of resting-state fMRI disruptions in 22qDel are related to spatial gradients of inhibitory and excitatory neuronal gene expression in post-mortem brain tissue from typical adults. This multimodal approach aims to elucidate brain biomarkers and neurobiological mechanisms related to genetic and clinical risk factors for psychosis spectrum disorders. To facilitate this research, the proposed training plan includes coursework, workshops, and professional development activities related to analysis of multi-site data, longitudinal data analysis, neurogenetics, and science communication. The Bearden Lab and Neuroscience Interdepartmental Program at the University of California Los Angeles will provide the ideal academic environment for the proposed training and research plan.

NIH Research Projects · FY 2026 · 2023-09

PROJECT SUMMARY/ABSTRACT Depression is a prevalent condition that disproportionately afflicts women, including up to 20% of women during pregnancy. Selective serotonin reuptake inhibitors (SSRIs) used to treat antenatal depression in pregnant women vary greatly in their efficacy across individuals, and there are concerns that maternal SSRI treatment detrimentally affects fetal development to elevate risk for adverse obstetric outcomes and neurodevelopmental abnormalities in the offspring. Research is needed to identify the factors that regulate the efficacy of SSRIs and that modify maternal-fetal responses to SSRI treatment during pregnancy. Understanding the variables that regulate the effects of SSRIs is paramount to identifying safer and more efficacious treatments for depression in pregnant women and to limiting harmful effects of maternal SSRI treatment on developing offspring. The gut microbiome is emerging as one such factor that interacts directly and indirectly with SSRIs. We recently discovered that SSRI treatment during pregnancy alters the composition of the maternal gut microbiome, and that depletion of the maternal gut microbiome modifies fetal brain responses to maternal SSRI treatment. We further determined that the SSRI-associated gut bacterium Turicibacter sanguinis binds SSRIs through a previously uncharacterized protein orthologue of the mammalian serotonin transporter. This evidence raises the important question of how the gut microbiome impacts maternal and fetal responses to SSRI treatment for antenatal depression. To address this, we will define the impact of SSRI treatment on the function of the maternal gut microbiome in pregnant mice, in pregnant women, and in the SSRI-binding bacterium T. sanguinis (Aim 1). We will further test the hypothesis that variations in the maternal gut microbiome modify the pharmacokinetics of SSRI absorption and distribution across the maternal-fetal interface (Aim 2). Finally, we will determine effects of the maternal gut microbiome on the efficacy of SSRI treatment against symptoms of antenatal depression (Aim 3). We will additionally assess how the maternal gut microbiome impacts the detrimental effects of maternal SSRI treatment on neurodevelopment and behavior of the offspring. Findings from our study will reveal fundamental mechanisms for microbial interactions with SSRIs, with the potential to transform interventional strategies for treating symptoms of antenatal depression, while limiting adverse consequences of SSRIs on developing offspring.

NIH Research Projects · FY 2025 · 2023-09

PROJECT SUMMARY/ABSTRACT Damage to the vascular endothelium is responsible for cardiovascular disease, which is the leading cause of mortality in patients with autoimmune diseases. In idiopathic inflammatory myopathies (IIM), this process is particularly relevant as vascular damage is implicated in the disease pathogenesis as well as its associated major organ complication, interstitial lung disease (IIM-ILD). However, the precise mechanisms of ongoing endothelial activation and vascular damage in IIM are currently not well understood. The proposed research addresses a critical knowledge gap regarding the pathogenesis of vascular injury in IIM and IIM-ILD by investigating a novel mechanism for perpetuation of vascular damage mediated by dysfunctional high-density lipoproteins (HDL). HDL normally protects vascular endothelium from damage, but under certain inflammatory states, HDL may lose its anti-inflammatory properties and become a dysfunctional, pro-inflammatory particle that promotes endothelial cell damage. Our recent work demonstrates that the antioxidant function of HDL and HDL-associated antioxidant enzyme paraoxonase-1(PON1) activity are impaired in patients with IIM, and correlate with more active disease. The gut microbiome has shown strong associations with HDL and is known to impact cardiovascular and lung health. Our preliminary results of the gut microbiome in IIM and controls show a link between microbial composition and PON1 activity. We hypothesize that changes in HDL- associated enzymes and proteins, pro-inflammatory bioactive mediators (BLM) and the gut microbiome result in dysfunctional HDL, leading to the perpetuation of vascular endothelial damage and ultimately increased IIM disease burden. We will use a longitudinal IIM cohort and comprehensive assessments of HDL function to study the following specific aims: (1) evaluate the association between abnormal HDL function and vasculopathy; (2) determine whether changes in abnormal HDL function over time correlate with disease burden; and (3) examine the association of gut microbiome with HDL function and disease burden. The project will be conducted at the University of California Los Angeles (UCLA) with the support of a multidisciplinary team of mentors comprised of nationally recognized experts, and numerous resources of a major academic institution, including graduate courses, core facilities, and career development seminars. Completion of the proposed project and training plan will facilitate advanced training in the following areas: (1) microbiome study design, data collection sequencing and analysis; (2) laboratory techniques and statistical analysis methods for complex biomarker panels; and (3) disease outcome measures in IIM, including a quantitative imaging scoring system in IIM-ILD. Training in these areas will provide a foundation to achieve my long-term goal, to be an independent physician-scientist combining clinical, experimental and computational approaches to detect unique microbial and lipid function signatures that impact disease-related vascular damage, in order to identify novel therapeutic targets that may improve the lives of patients with autoimmune diseases including IIM.

NIH Research Projects · FY 2025 · 2023-09

Project Summary / Abstract A long-term goal of our research is to understand how cortical neurons become tuned to stimulus features and organized into cortical maps. Our working hypothesis is that the spatial distribution of ON/OFF inputs from the geniculate seeds simple-cell receptive fields, cortical columns, and maps. This hypothesis stands in stark contrast with the textbook account that cortical receptive fields and maps develop through self- organizing processes driven by structured, spontaneous activity in the LGN. To test our hypothesis, we seek to investigate predicted correlations between the organization of the thalamocortical projection and the receptive fields and tuning of cortical neurons. In Aim 1, we seek to determine if there is a link between the spatial layout of ON/OFF domains, receptive field structure, and tuning in primary visual cortex. In Aim 2 we will classify and cluster thalamocortical boutons according to their responses to a rich set of visual stimuli, allowing us to reconstruct the tiling of the visual field by different classes of geniculate neurons. We will then study the spatial distribution and clustering of geniculate afferents into the cortex. Finally, in Aim 3, we will investigate a predicted correlation between the organization of thalamocortical projections and cortical organization in single animals. We will achieve this by simultaneously imaging the activity of thalamic boutons and cortical neurons using dual-color imaging. The proposed studies are significant as they test the possibility that an imbalance between the ON and OFF responses from the periphery provides a scaffold for the development of simple cell receptive fields and cortical columns. A positive outcome would prompt a revision of our current views of the development of the cortical architecture.

NIH Research Projects · FY 2024 · 2023-09

PROJECT ABSTRACT The goal of this project is to develop a new method for fiber sampling. The method currently used for airborne sampling of carbon nanotubes (CNTs) is adapted from micrometer-scale asbestos sampling. To achieve our goal, we will study surface properties of different CNTs and sampling filters contributing to efficiency, develop a novel image analysis protocol with our algorithms, use a newly developed nanoparticle (NP) isokinetic diffusion sampler, simulate and elucidate the particle behavior, and produce a new method suitable to CNTs sampling. Burden: Exposure to airborne CNTs has been of highest concern following their designation as a potential human carcinogen. The potential health effects of CNTs have shown some similarity to those of asbestos fibers in animal models. CNTs global market is projected to reach $103.2 billion by 2030 with 16.3% annual growth. The fiber sampling method used for asbestos has been a recommended method for sampling CNT fibers. CNTs contain individual fibers with diameters that are one tenth to one hundredth that of asbestos fibers. The NIOSH Methods 7402 was found to be very challenging and time consuming for identifying a few very fine CNT fibers on a grid sample under electron microscopy. Questions raised by this challenge include whether the number and size of CNT fibers collected by 7402 method are representative of those in the air, whether these sizes are affected by the sampling and extensive processing required by the method, and how the exposure to fine fibers can be quantified properly to evaluate associated health effects when this method is not yet validated for CNT. Need: A new method and technique for sampling fine fibers to 1) collect fibers efficiently in the sampled air without loss, 2) directly analyze the collected fibers with minimal processing of the sample, and 3) easily count the fibers to obtain the concentration and size, which will resolve the lack of accuracy of exposure measurements and the significant time requirement of sample analysis. When used for CNTs, the collection efficiency and performance of sampling and analysis must be evaluated. It is critical to design a new sampling substrate because the currently used mixed cellulose ester (MCE) filter for collecting asbestos may not be suitable for collecting CNTs. The fibers collected on the MCE filter need to be processed for transfer to a grid for analysis, small fibers can be agglomerated or lost. A new sampling method and substrate that can effectively collect fibers to be analyzed directly will prevent the loss or change of collected fibers through the transfer process. Impact: The wide range of applications that use fiber materials such as CNTs, asbestos and fiberglass and other NPs can employ the developed protocol and method to effectively quantify the exposure level in terms of fiber/particle concentration. This information may change the current measurement metric for CNTs from mass concentration to fiber/particle number concentration. Using more precise counting can characterize the exposure concentration at a very low and difficult to measure mass concentration and provide associations to related health effects for a measurement below the current limit of mass quantification for CNTs.

NIH Research Projects · FY 2026 · 2023-08

PROJECT SUMMARY The overall goal of this proposal is to understand sex differences in the neural regulation of feeding, specifically how the anorexogenic effects of estradiol are modulated by a new hypothalamic node of the feeding circuit. Previous research identified somatostatin (SST)-producing neurons as part of the neural circuit that controls feeding, but sex differences were not explored. We find that activating SST neurons in the region that spans the tuberal and ventromedial nuclei of the hypothalamus increases feeding in male and female mice. However, ablating these neurons decreases feeding only in females, only during the high-estrogen phase of the estrous cycle, and only when their body mass is relatively low. These findings are consistent with previous studies but go further to reveal a context-dependent role for SST neurons in the regulation of feeding. We hypothesize that SST neurons of the tuberal nucleus are a sex-specific, modulatory node within the brain that can mask the anorexic effects of estradiol when energy reserves are low. The proposal outlines studies in mice to determine how SST neuronal function is modulated by both reproductive and metabolic cues. In Aim 1, we use cell-specific manipulations combined with gonadal hormone manipulations to reveal how SST neuron function is modulated by reproductive state. In Aim 2, we use cell-specific manipulations combined with manipulations of body mass and adiposity to reveal how SST neuron function is modulated by metabolic state. In Aim 3, we use fluorescent labeling and flow cytometry followed by RNA-sequencing (flow-Seq) to assess how SST neurons may be responsive to reproductive and metabolic conditions and whether this differs by sex. Together, these studies will help us understand how neural circuits integrate multiple peripheral signals to fine tune behavior and physiology across dynamic states.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY The goal of this renewal application is to provide support for mentoring of trainees and junior investigators in the areas of sleep disorders and sleep health among patient populations who are “at risk.” The applicant’s current research program focuses on treatment of sleep disorders in populations who have not been studied or who have achieved less benefit from current evidence-based interventions. This program provides rich opportunities for mentees to experience direct engagement in patient-oriented sleep research. Currently funded work focuses on veterans with comorbid insomnia disorder and post-traumatic stress disorder (PTSD) for whom standard cognitive-behavioral therapy for insomnia (CBT-I) is less acceptable and less efficacious than among individuals without PTSD. Based on emerging evidence that the theoretical underpinning and specific exercises of Acceptance and Commitment Therapy (ACT) present a viable approach to improving sleep when combined with evidence-based behavioral strategies, a novel ACT-based insomnia treatment, called "Acceptance and the Behavioral Changes to Treat Insomnia (ABC-I) is being tested in a clinical trial. ABC-I combines core behavioral components (sleep restriction, stimulus control, sleep hygiene, relaxation) with ACT-based techniques will be evaluated in a randomized trial. Using a comparative effectiveness design (n=200 randomized to ABC-I or cognitive-behavioral therapy for insomnia (CBT-I)), the primary aims of the study are to evaluate the benefits of ABC-I in reducing insomnia severity (non-inferiority) and PTSD symptoms (superiority) as compared to CBT-I. Additional aims address potential mechanisms of change from before to after treatment and explore potential ancillary benefits in terms of reducing other symptoms. The proposed analytic plan will simultaneously address superiority of ABC-I over CBT-I for improving PTSD symptoms and non-inferiority of ABC-I compared to CBT-I for improving insomnia symptoms. In addition to other ongoing and recently-completed projects, the study provides rich opportunities for trainees to engage in all aspects of patient-oriented research on sleep disorders, including direct interaction with research participants and engagement with data analysis and dissemination of findings. The research environment at UCLA and VAGLAHS is rich with opportunities for learning and for collaborative mentoring in areas of sleep health and sleep disorders. Building upon activities during the prior K- 24 award, the applicant will engage in formal leadership training and engage the support of a Leadership Development Council.

NIH Research Projects · FY 2026 · 2023-08

Enter the text here that is the new abstract information for your application. This section must be no longer than 30 lines of text. Compassionate end-of-life (EOL) care is foundational to medicine, but providing patients and families in safety-net hospitals (SNHs) with the sense that they are physically and emotionally supported during a patient’s terminal hospitalization can be challenging. These public hospitals operate under significant budgetary constraints while serving patients with limited or no health insurance. Despite the critical importance of high-quality EOL care, its delivery is often complicated by communication difficulties and differing expectations between families and medical teams. EOL experiences in intensive care units (ICUs) can lead to significant emotional strain for family members. Palliative care interventions are needed, but implementation is frequently limited by operational and financial constraints. The 3 Wishes Project (3WP) is a palliative care intervention that aims to achieve a dignified and compassionate EOL experience by empowering the clinical team to elicit and fulfill small wishes for critically ill patients who are dying in the ICU. Although the 3WP has been shown to improve a family’s experience of their loved one’s EOL care, ease bereavement, and enhance clinician work satisfaction in academic centers, it has not been implemented and evaluated in hospitals with limited operational capacities. We believe that this innovative program can improve the EOL experience in SNHs, although it must be adapted to the contextual differences and needs of low-resource hospitals. We propose to obtain and use stakeholder input to customize a multi-component 3WP Toolkit that will facilitate 3WP implementation in SNHs. Using the tailored Toolkit, we will implement and evaluate the 3WP in the three SNHs within the Los Angeles County Department of Health Services. We will conduct a pragmatic type 2 hybrid effectiveness-implementation study to evaluate the quality of EOL ICU care, bereaved families’ psychological symptoms, and clinician burnout as compared to usual care. We will use the Consolidated Framework for Implementation Research (CFIR) and the RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) framework to guide a mixed-methods evaluation of the 3WP implementation in SNHs. Our research team brings expertise in EOL care, clinical implementation, and research in public hospital systems. We anticipate that this evaluation will provide practical insights for applying innovative EOL interventions in public hospitals facing resource constraints. The findings may serve as a guide for wider application of the 3WP across a variety of hospital environments.

NIH Research Projects · FY 2025 · 2023-08

Project Summary/Abstract Diagnostic imaging is a standard part of trauma assessment, but access to imaging is often extremely limited in low and middle-income countries, where most injury deaths occur. Trauma death rates in Cameroon are higher than surrounding countries. Failure to diagnose hemorrhagic shock has been implicated in death analysis of the Cameroon Trauma Registry and by the National Trauma Quality Improvement Committee as a key root cause of preventable deaths. Currently, fewer than half of trauma patients in Cameroon receive diagnostic imaging. Development of a provider-performed smartphone-based ultrasonography (SBU) program for trauma could increase diagnostic access and facilitate timely diagnosis and treatment of injuries but only if it is feasible and effective for the Cameroonian context. The long-term goal of this research is to reduce the burden associated with injury in Cameroon. This study’s overall objective is to expand diagnostic capacity to facilitate timely diagnosis of injury and reduce injury burden. The study hypothesis is that implementation of a provider-performed SBU program is a feasible and effective method of expanding access to diagnostic imaging for trauma patients in Cameroon. To accomplish the objective, this study will pursue three specific aims for the R21 phase: 1) Evaluate the educational efficacy of a SBU training curriculum in short- and medium-term skill and knowledge acquisition among Cameroonian trauma providers; 2) Evaluate the feasibility of a provider- performed SBU pilot in Cameroon; 3) Assess the acceptability of an SBU pilot among Cameroonian trauma stakeholders. If the R21 transition milestones are met, the R33 phase will pursue three specific aims: 1) Assess diagnostic accuracy of provider-performed SBU on trauma patients; 2) Evaluate the effectiveness of a provider-performed SBU program in expanding diagnostic capacity for trauma; 3) Test associations between SBU program implementation and trauma outcomes. Validating SBU as a feasible and effective method to expand diagnostic capacity will remove a major roadblock to prompt trauma care and provide a critical target for reducing the detrimental impact of injury on this population. Embedded in the study approach is the training of clinicians in health systems research and strengthening of mHEALTH capacity in Cameroon which will support development and research across health sectors. A standardized SBU training and implementation protocol could be rapidly scaled-up for wider implementation throughout Cameroon and validated in other LMIC contexts.

NIH Research Projects · FY 2025 · 2023-08

ABSTRACT Despite significant advances in the understanding of the neurobiology of alcohol use disorder (AUD), there is a gap in the translation of these insights into clinical applications. Translational research in AUD is facilitated by the use of experimental manipulations and theoretical constructs that can be studied across species. Towards advancing translational research in AUD, the PI completed an Exploratory/Developmental Project entitled: “Modeling alcohol reward and reinforcement in the human laboratory” (R21 AA022752). The objective was to develop and test a translational task of motivation for alcohol in humans. To do so, we combined alcohol challenge with progressive ratio self-administration methodologies. Alcohol was administered intravenously using the Computer-Assisted Self-Infusion of Ethanol (CASE) system. At BrAC = 0.06 g/dl, participants completed a progressive ratio self-administration task in which they were allowed to work to be infused more alcohol following a progressive ratio schedule. The alcohol self-administration task captures motivation for alcohol and mirrors preclinical methodologies, ideal for testing of translational hypotheses. In addition to developments in the “outcome side” of the modeling approach, the “predictor side” comprised of AUD phenomenology has progressed towards clinical translation. The Addiction Neuroclinical Assessment (ANA) proposed to parse AUD phenomenology into three domains, namely incentive salience, negative emotionality, and executive dysfunction. Our research group has recently provided an independent replication of the ANA framework in a sample of 1,679 heavy drinkers. Together with the innovation in outcome assessment (i.e., progressive ratio self-administration in humans), the ANA framework can inform staging of AUD progression and as such, motivation for alcohol in humans provides an ideal behavioral science outcome. The proposed R01 application builds upon the extensive work from our laboratory on the development of a translational task for drinking motivation in humans. It does so by testing the three dimensions of the ANA for their effects on alcohol motivation in individuals with AUD.

NIH Research Projects · FY 2026 · 2023-08

Project Summary High-quality care throughout the trajectory of illness of Alzheimer's disease and Alzheimer's disease- related dementias (AD/ADRD) has been shown to be associated with a better quality of life, lower caregiver distress, and reduced use of acute and long-term care. However, racial and ethnic (R&E) minoritized persons with AD/ADRD often receive poorer quality care than White patients, including lower rates of advance directives, reduced receipt of anti-dementia medications, and increased end-of-life hospitalizations. Although governmental and institutional policies influence R&E diversity in medical education/training and work environments, little is known about how R&E diversity in medical education, residency training, and health system leadership affect R&E disparities in AD/ADRD care. This knowledge gap has hindered efforts to develop interventions that could effectively eliminate disparities in AD/ADRD care. The proposed study will address these important knowledge gaps by applying the quasi-experimental methods to the comprehensive data on patients, physicians, medical schools, residency programs, and health systems we will develop by linking 7 nationally-representative databases (Medicare Claims Data, Consumer Assessment of Healthcare Providers and Systems Data, Doximity Physician Data, Association of American Medical Colleges Medical School Data, American Medical Association Residency Program Data, RAND Health System Data, and American Hospital Association National Health Care Governance Survey Data). In Aim 1, we will determine the effect of the R&E diversity of medical school student bodies from which physicians graduated on disparities in AD/ADRD care, by applying the quasi-experimental instrumental variable method using the state affirmative action bans as an instrument. The state affirmative action bans serve as an ideal instrument because they are strongly associated with medical school student body diversity, but do not directly affect AD/ADRD care. In Aim 2, we will determine the effect of 4 residency program characteristics (higher R&E diversity of residents, presence of cultural competence awareness program, instruction in medical Spanish or other non-English languages, and rotation at the county and safety-net hospitals) on R&E disparity in AD/ADRD care, using the propensity score matching method. In Aim 3, we will determine the effect of R&E diversity of health system boards on disparities in AD/ADRD care, by applying the propensity score matching method. This project will provide a robust evidence base for policymakers to develop policy interventions (e.g., increasing R&E diversity and introducing the cultural competency awareness program at medical schools, residency programs, and health systems) that could effectively mitigate R&E disparities in AD/ADRD care. The research team consists of investigators with expertise in all relevant fields (Alzheimer's disease and dementia research, R&E disparity research, medical education and training, organizational behaviors, physician and health system performance, and econometric and statistical methods) to conduct this innovative research.

NIH Research Projects · FY 2024 · 2023-08

PROJECT SUMMARY/ABSTRACT Wildfire smoke exposure is thought to be responsible for increased morbidity and 339,000 annual deaths, but little is known about cardiovascular (CV) effects. It is well known that fine particulate matter (PM2.5) is the air pollution component most strongly linked to morbidity and mortality, mostly due to ischemic CV diseases. Extending these effects to biomass burning aerosol (BBA) generated from wildfires is not directly translatable since most studies on CV toxicity of PM2.5 investigate urban PM2.5 which has significant differences in chemical and toxicological profiles compared to BBA. Some suggest BBA exhibits higher CV toxicity compared to non- wildland sources, which may be due to the ability of BBA components to disrupt pulmonary Fe homeostasis. BBA are enriched in atmospheric humic-like substances (HULIS), complex water-soluble organics that have been shown to disrupt pulmonary Fe homeostasis resulting in a functional Fe deficiency that can lead to Fe overload, oxidative stress, and in inflammatory response. Importantly, no study has every investigated the impact of BBA or HULIS exposure on the progression of atherosclerosis. Our central hypothesis is BBA, and HULIS in particular, disrupts Fe homeostasis in pulmonary and systemic tissues leading to increased inflammation and worsened atherosclerosis. In this K99/R00 MOSAIC application, we propose to use laboratory generated BBA in cell culture and controlled in vivo inhalation exposures. In Aim 1, murine alveolar epithelial and alveolar macrophage cultures will be exposed to BBA and HULIS for assessment of changes in Fe homeostasis, oxidative stress, inflammation, and proatherogenic metabolites. We will employ Hepcidin Knockout (HKO) mice as models of Fe overload in alveolar epithelial cells and alveolar macrophages. Aim 2 explores if in vivo BBA exposure exacerbates atherosclerotic lesions in low density lipoprotein receptor knockout (Ldlr-KO) mice on a high fat diet and whether Fe overload in pulmonary and systemic tissues play a role. Aim 1 is proposed to be completed by the candidate under the mentorship of Dr. Jesus Araujo during the K99 phase. Aim 2 will be independently facilitated by the candidate during the R00 phase following appointment to a faculty position. In addition to this research, this K99/R00 MOSAIC will provide support for further training and career development for the candidate. The applicant's long-term goal is to be an independent faculty at a tier-1 university and continue air pollution toxicology research. To achieve this, we propose three training goals for the K99 phase: (1) Enhance Biomedical Education, (2) Develop Skills in In Vitro Methods and (3) Acquire Training in Biostatistics. Dr. Araujo's lab at the David Geffen School of Medicine at UCLA is an ideal environment for successful completion of K99 research as well as achieving training goals and preparing the candidate for saucerful transition to independence. Support in the R00 phase will facilitate the candidate's transition to independence simultaneously advancing the candidate's and NIH diversity goals.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY/ABSTRACT The mammalian heart possesses a poor ability to regenerate after myocardial infarction and heals via a fibrotic repair response. Scar tissue increases the hemodynamic burden on the remaining cardiac muscle and over time, the ventricle fails leading to the development of heart failure. Myocardial infarction contributes to almost 40-70% of all cases of heart failure and 700,000 patients are annually diagnosed with heart failure in the United States alone. The main thrust of cardiovascular pharmacology for the treatment /prevention of heart failure after heart attacks has centered on chronic antagonism of the sympatho-adrenal-angiotensin- aldosterone axis (Beta blockers, ACE inhibitors, Angiotensin receptor blockers and aldosterone antagonists) but despite available pharmacological therapies, the 5 year survival rate of heart failure is less than 50%. There thus exists an immense unmet need to identify novel pharmacological strategies for the treatment and prevention of heart failure. We have recently demonstrated the role of a specific ectonucleotidase, ENPP1 (ectonucleotide pyrophosphatase/ phosphodiesterase 1) in cardiac repair following myocardial infarction. ENPP1 is induced by orders of magnitude after myocardial infarction and show that hydrolytic products generated by ectonucleotidase activity contribute to inflammation and impair the cardiac injury response. Using genetic loss of function approaches, we showed that inhibition of ENPP1 in the infarcted heart leads to decreased non- myocyte cell death, decreased inflammation and significantly superior post infarct cardiac function. Considering these observations, in collaboration with an antibody engineering biotech company, we in this proposal have engineered a humanized monoclonal antibody targeting ENPP1 as a therapeutic biologic to treat post infarct decline in cardiac function. We provide proof of concept efficacy studies demonstrating the ability of the administered clinical candidate to modulate inflammation in the infarcted heart and lead to significantly better preservation of post infarct function and decreased post infarct ventricular remodeling. Further development of the monoclonal antibody combined with definitive preclinical studies in humanized mice models as well as large animal infarct models forms the substance of the proposal. Using a variety of “omics” approaches and genetically engineered mice, we will also interrogate in depth the downstream pathways that are affected by the ENPP1mAb to exert salutary effects on cardiac repair and post infarct heart function. If our studies are successful, the proposal will directly lead to the identification of a clinical monoclonal antibody candidate to attenuate post infarct cardiac remodeling and dysfunction.

NIH Research Projects · FY 2024 · 2023-08

Abstract Darobactin A is a post-translationally modified peptide antibiotic recently isolated from photorhabdus symbionts present in nematodes. The molecule contains a novel pattern of internal oxidative cross links that result in its pre-organization as a beta sheet mimetic. The compound binds to the beta barrel protein BamA and inhibits chaperone functions essential for folding of bacterial outer membrane proteins. Darobactin A is broadly active against gram-negative pathogens in vitro and in animal models of infection. The dar operon encodes a single radical SAM enzyme that catalyzes formation of both oxidative cross links observed in the natural product. The mechanism(s) behind this remarkable outcome is not yet known. We have expressed and purified recombinant His-tagged DarE. When properly reconstituted with iron and sulfur under anaerobic conditions, iron titration data indicates the enzyme contains three iron sulfur clusters and it rapidly generates 5dAdo from SAM – indicating reconstituted DarE is active as a SPASM enzyme. Here we propose a combined chemical synthesis and biosynthesis program to study DarE enzymology and to engineer semi- synthetic forms of the natural product that can be produced on scale. Such studies hold considerable promise. It has been nearly 60 years since a new class of antibiotics active against gram negative infections have been developed.

NIH Research Projects · FY 2024 · 2023-08

Abstract Autism spectrum disorder (ASD) affects one in 44 children. 1 Early diagnosis is critical for optimizing outcomes, yet children are not typically diagnosed until 4 years of age.2 In concert with early behavioral signs, early neural markers could identify toddlers at risk of developing ASD to aid earlier diagnosis and targeted interventions. Neuroimaging studies have primarily examined structural brain abnormalities in toddlers at high risk of developing ASD3. A growing body of work provides evidence for functional brain network connectivity alterations in older children with ASD (7-12 years of age).4 While innovative dynamic functional magnetic resonance imaging (fMRI) methods reveal candidate brain networks of dysfunction underlying the heterogeneity of the disorder and symptom severity in older children with ASD,567,8no study to date has evaluated the relationship between brain network dynamics and behavioral outcomes in toddlers with ASD. Restricted and repetitive behaviors (RRBs), core symptoms of ASD,9 are particularly understudied. The goal of this project is to identify early functional brain biomarkers of ASD and brain-behavior relationships with RRB outcomes across mixed clinical and typically developing (TD) groups. This study will utilize a dataset previously collected by the UCSD ACE Center comprised of toddlers (12-36 months, n = 231) who were identified as either TD or at-risk for a developmental disability using an early screening form (Communication and Symbolic Behavior Scales Developmental Profile; CSBS-DP).10Some toddlers were later diagnosed with ASD (n = 89), TD (n = 70), other diagnosis (n = 72; Language Delay, Developmental Delay, and Autism Features). Since the sample includes multiple diagnostic groups, this dataset offers a unique opportunity to examine early brain biomarkers for ASD and RRBs across diagnostic categories, as envisioned by the Research Domain Criteria (RDoC) approach.11 Early behavioral indicators alone do not always clearly indicate which children will go onto to develop ASD.12 The results from this study may lead to the development of reliable biomarkers to identify children at risk for ASD in concert with overt behavioral signs of the disorder. Neural biomarkers of ASD and RRBs will in turn lead to earlier and more efficient diagnosis and treatments. This work builds upon the applicant’s previous research experience at the UCSD ACE Center collecting neuroimaging data from toddlers.13 The applicant has previously examined dynamic brain biomarkers of RRB symptoms in older children with ASD (8-12 yo),7,14–16 reviewed the brain biomarker literature in toddlers with ASD,3analyzed large lifespan neuroimaging datasets (n = 601), and gained a foundation in statistics and clinical neuroscience. Through formal coursework and individual meetings, the applicant plans to engage in four major areas of training: (1) cutting-edge analyses to assess brain dynamics using functional neuroimaging data, (2) sophisticated statistical approaches for modelling longitudinal data, (3) considerations for conducting research with young children at risk for autism, and (4) career development.

NIH Research Projects · FY 2025 · 2023-08

Abstract: The global obesity epidemic drives the high prevalence of cardiometabolic disorders (CMDs), including type 2 diabetes (T2D), and non-alcoholic fatty liver disease (NAFLD). Epidemiological studies have also established strong sex differences in CMDs. Obesity-induced low-grade inflammation and insulin resistance in adipose tissue (AT), their deteriorating impacts on the efficacy of adipogenesis, and subsequent ectopic fat storage into other cardiometabolic tissues, particularly liver, have been proposed as the key drivers of the CMD risks related to obesity. However, the mechanisms promoting the transitions from health-to-disease states in human fat depots have remained largely elusive. We hypothesize that there are transcriptional inflammatory markers and cell-type-specific changes in open chromatin pertinent to health-to-CMD transitions that can be discovered using single cell level and bulk omics analyses in fat cell-types and tissue. We also hypothesize that by elucidating molecular responses to obesity-related stimuli during adipogenesis we can discover candidate variants and genes with functional priors for formal identification of gene-sex and gene-environment interactions (i.e. GxSs and GxEs) underlying obesity-induced health-to-CMD transitions in large biobanks. In Aim 1, we will generate sex- and context-specific bulk and single cell level transcriptomics (RNA-seq) and epigenomics (ATAC- seq) data in two obesity-relevant fat depots, i.e. subcutaneous and visceral AT, to identify epigenetic and transcriptional markers for health-to-CMD transitions in six health-to-CMD stages comprising lean, overweight, and obese males and females with and without prediabetes, T2D, and NAFLD. We will also use existing serum samples to discover health-to-CMD transition biomarkers among the genes that differ between the six health/disease states and encode secreted proteins. We will test the top results for replication in independent omics cohorts, including Mexicans. In Aim 2, we will use a new function-to-variants omics approach to discover GxSs and GxEs involved in early transitions from health to CMD in males and females. We will generate functional genomics data in CMD-relevant human primary preadipocytes, extracted from fresh AT of normal weight, metabolically healthy males and females. These preadipocytes will be differentiated with and without key inflammatory stimuli to discover stimuli-responsive adipogenesis genes and cis-regulatory elements (CREs) that harbor regulatory variants in diverse populations. Subsequently, these variants will be fine-mapped using massively parallel reporter assay in (pre)adipocytes and functionally characterized using extensive variant-to- gene-linkage analysis and genomic perturbations (CRISPR and siRNA). The identified candidate SNPs will be tested for GxE and GxS effects on health-to-CMD transitions in large biobanks to verify their role in these critical transitions. Our preliminary results and ample previous experience with integrative multiomics approaches of CMDs provide a strong prior scientific rigor for the proposed Aims, and overall, accomplishing our Aims has a great potential to develop personalized strategies that prevent or postpone the onset of obesity-related CMDs.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY/ABSTRACT - Overall Our Program Project Grant (PPG) focuses on the complex interplay between the chronically infarcted heart and sympathetic nervous system (SNS), with the goal of defining precise mechanisms of ventricular arrhythmias and sudden cardiac death. The overarching objective of the PPG is to test ‘The Spatiotemporal Heterogeneity of Neurotransmitter Release Hypothesis’ that postulates scars alter the ultrastructure of nerves and result in non-uniform neurotransmitter release in the myocardium which is a crucial and proximate cause of lethal arrhythmias. We propose to 1) understand the maladaptive interactions between the chronically injured heart and the SNS, and 2) using this framework to investigate the mechanisms by which chronic vagal nerve stimulation (VNS) as a prototypical neuromodulation therapy exerts its beneficial effects and gain broader insights. Our PPG team has made seminal discoveries in cardiac neural control, cardiomyocyte electrophysiologic function, control of ventricular tachycardia circuits at the myocardial level, and the complex multicellular paradigms that underlie sympathetic neuronal dysfunction within stellate ganglia, the major source of enhanced postganglionic sympathetic drive to the injured heart. These discoveries are relevant to the electrophysiologic instabilities that underlie susceptibility to lethal ventricular arrhythmias and are a result of the multifaceted collaborations between our PPG project & core leaders, and the broader study team. In Project 1, Dr. Shivkumar and his colleagues will utilize novel 3D cardiac electrical mapping approaches combined with real time in vivo neurotransmitter/neuropeptide detection in normal and chronically infarcted beating hearts to define the mechanisms of physiologic and pathophysiologic nerve-myocyte interactions. In Project 2, Dr. Harvey and colleagues will study, at the single myocyte level, how various neurotransmitters (alone and in combinations seen in the normal and diseased myocardial milieu) impact cardiomyocytes from normal hearts and from the scar-border zone. In Project 3, Dr. Ajijola and his colleagues will investigate the source of excessive and dysfunctional sympathetic neurotransmission to the heart, specifically inflammation in the stellate ganglia. Project 3 will investigate how maladaptive interactions between neurons and other cell types such as glia and immune cells lead to dysfunctional control of the chronically injured heart. These three component projects will be supported by two scientific cores, led by Drs. Ardell and Ajijola and an administrative core led by Dr. Shivkumar. The scientific cores will provide a stream of normal and diseased human hearts and stellate ganglia for studies in Projects 1-3, as well as high throughput tissue clearing techniques and high-resolution imaging (Core A). The cores also aim to reproducibly generate experimental porcine models and oversee technologies for in vivo neuropeptide/neurotransmitter release (Core B). Our PPG team is confident in its success as we are building on pre-existing intellectual and deep collaborative relationships among the teams and are enthusiastic about the novel hypotheses being tested utilizing innovative tools and approaches.

NIH Research Projects · FY 2025 · 2023-08

Project Summary/Abstract This proposal describes a mentored physician-scientist training program to uncover novel genes and networks in pulmonary arterial hypertension (PAH) using an integrative multiomics approach. The candidate is currently developing his academic career in the Division of Pulmonary & Critical Care at the David Geffen School of Medicine of UCLA. His long-term goal is to develop more effective targeted therapies for PAH patients informed by a deeper knowledge of the pathogenic mechanisms. Under the guidance of his mentors Drs. Mansoureh Eghbali and Xia Yang, the candidate will develop a unique cross-disciplinary skillset in integrative systems, single-cell, spatial and experimental biology that will facilitate his transition to research independence in the field of PAH. PAH remains an incurable disease characterized by irreversible pulmonary vascular remodeling, poor quality of life, and guarded long-term prognosis. Leveraging a well-powered cohort integrating the latest omics and computational methodologies is critically needed to identify candidate molecular drivers in PAH lungs as potential therapeutic targets. With access to RNA sequencing of the largest biobank of human PAH and control lungs to date (n=148), we have identified, by co-expression network analysis, a module of 266 genes (which we refer to as the “pink” module) that is strongly associated with PAH lungs. Through multimodal integration with right heart catheterization data, histological analyses, and genome-wide association studies (GWAS), we found the pink module is not only transcriptionally upregulated in PAH lungs, but also associated with increased hemodynamic severity, vascular remodeling, and genetic risk of PAH. Our preliminary data suggests pink module genes are 1) dysregulated in pulmonary vascular cells, 2) enriched in pathways relevant to pulmonary vascular remodeling such as endothelial-mesenchymal transition and Wnt signaling, 3) and may be candidate molecular drivers of PAH, such as ANTXR1, an integrin-like glycoprotein strongly implicated in various cancers but never studied in PAH. Given the mounting preliminary evidence for the importance of the bulk lung-derived pink module, a deeper investigation into its cell-specific role in PAH pathogenesis is needed to advance our understanding of the molecular drivers of PAH lungs and identify new therapeutic targets. We hypothesize that the pink module drives vascular remodeling in PAH through its dysregulation within pulmonary vascular cells. To test this hypothesis, we will 1) resolve the specific cellular context in which the pink module is dysregulated in PAH lungs using single- nucleus RNAseq and spatial transcriptomics and 2) determine the effects of in vitro knockdown of a pink module candidate driver gene, such as ANTXR1, in PAH pulmonary vascular cells. The proposed studies will utilize a combination of cutting-edge multiomic approaches and experimental biology to provide greater insight into a novel PAH-associated gene set derived from a large lung biobank, and will provide a foundation for my own lab and future R01 that will focus on basic mechanistic and translational studies.

NIH Research Projects · FY 2026 · 2023-08

Project Summary Older adults vastly underutilize evidence-based preventive health services that are proven to reduce serious illness, morbidity and mortality. In fact, fewer than half of adults aged 65 and older are up-to-date on evidence- based cancer screenings and vaccinations recommended by expert committees (e.g., the USPSTF and CDC/ACIP). Those at greatest risk for receiving poor preventive care include racial and ethnic minority groups and persons of low socioeconomic status. Yet interventions to remedy this underutilization in older adults have mostly targeted individual preventive health services, rather than the totality of services needed by patients. The 2011 Medicare establishment of the Annual Wellness Visit (AWV) is a great and underused opportunity to respond to the National Cancer Institute's calls for multilevel interventions that address both the supply and demand for vastly underutilized preventive health services. This free-to-the-patient AWV visit gives providers dedicated time to focus on preventive health services. We developed a multilevel intervention to increase AWV use that successfully increased AWV utilization in 3 small (2-5 provider) pilot practices. The intervention addresses the complexities of increasing AWVs at patient (demand for services), provider (supply of services), and practice levels. It combines electronic health record (EHR)-generated information and tools with practice redesign tools and approaches to inform providers and patients about the preventive health services needed by individual patients. This proposal's goal is to conduct a pragmatic trial to evaluate the effect of the intervention on increasing AWV and preventive health services utilization. We will implement the intervention in geographically and racially/ethnically diverse community- based practices, Federally Qualified Health Centers, and academic health system practices. Practices include small to mid-size primary care practices (including solo practices), which typically are under-represented in research. Specific aims of this study are to: 1) Evaluate the effect of the intervention on use of a) AWVs and b) USPSTF and CDC/ACIP-recommended preventive services in 3 different types of practice settings; 2) Evaluate the effect of the intervention on reducing racial/ethnic disparities in AWV utilization; and 3) Evaluate factors affecting implementation and sustainability of the intervention tools and approaches, implementation strategies, and intervention effect in diverse patient settings. Implemented via video conferencing and remote deployment of EHR tools, this low-cost intervention could easily be disseminated to small and solo practices across the country. The anticipated increase in patient use of preventive health services will improve population health and lower mortality, particularly in at-risk racial/ethnic minority patients.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY The human gut microbiome is intimately connected with health, with disruptions of its ecological composition associated with numerous diseases. Manipulations of the microbiome via fecal microbiome transplants (FMTs), in which microbial strains derived from healthy donor stool are introduced to a patient's gut community, have been found to be effective treatments for certain diseases, but less effective for others. In several cases in which FMTs fail to resolve a disease, invading strains fail to colonize, but it is unknown why, and even when strains do colonize, a healthy clinical outcome still is not guaranteed. Experimental evolution studies in mouse and bee microbiomes have shown that strains invading a host rapidly adapt, enabling colonization via physical adherence to host cells, competition with resident strains, and evasion of the host immune system. Despite this strong experimental support for the importance of adaptation during colonization, its role in the human gut microbiome has received little attention. Recently, we and others found that microbiome can evolve rapidly on months and even days, but the impacts of this rapid pace of evolution on the colonization process remains unknown. The main roadblock to linking adaptation and colonization lies in the statistical challenges of quantifying the full landscape of adaptations from noisy metagenomic data. Here I propose to develop new statistical methods that elucidate the evolutionary processes relevant for colonization in the microbiome and apply them to one of the largest datasets of FMT recipients. My lab's main goal is to understand how microbiomes evolve in a range of contexts and timescales. To this end, the overarching objective of my proposed MIRA research program is to elucidate the evolutionary processes that permit colonization of a strain. To fully quantify the mode, tempo, and targets of evolution in the gut microbiome and their relevance to colonization, we will develop novel methodology capable of detecting evolutionary events that are undetectable presently, including evolutionary changes (1) arising within hosts on short timescales and (2) across hosts on longer time scales. To illustrate the potential of our statistical innovations, we will study FMT recipients given that the identities of invading versus resident strains can be easily distinguished. However, FMTs represent an example of a more general phenomenon of colonization relevant to a range of cohorts and questions that my lab is studying, including the role of evolution in infants experiencing an influx of microbes at birth, strain turnover during consumption of antibiotics and probiotics, and spatial segregation of evolutionary adaptations needed for colonization along the gut. In sum, successful completion of this work will not only generate statistical innovations needed to quantify evolution in the microbiome, but also elucidate the importance of evolution in colonization, knowledge that promises to yield more efficacious microbiome therapies.

NIH Research Projects · FY 2025 · 2023-08

PROJECT SUMMARY / ABSTRACT Chronic HIV infection remains a public health challenge with nearly 38 million people worldwide living with HIV/AIDS. Despite the success of antiretroviral therapy in suppressing ongoing viral replication, numerous challenges remain including chronic inflammation and accelerated onset of comorbidities. Better understanding of the mechanisms contributing to these phenomena is imperative to further reduce comorbidities and improve treatment of HIV. The microbiome is comprised of trillions of diverse microbes (bacterial, fungal, viral), and multiple lines of evidence highlight the connections between the microbiome, mucosal immune system, and HIV-related inflammation. While the intestinal microbiome has been the focus of intense research, less is known about the role of the oral microbiome in health and disease. In non-HIV settings, the oral microbiome has been associated with increased risk of inflammation-related comorbidities such as cardiovascular disease. Recent evidence has also highlighted the connection between the oral and gut microbiomes, and increased colonization of aerotolerant “oral” bacteria in the gut has been observed in many inflammatory diseases, including HIV. Studies examining the oral microbiome in the setting of HIV are limited, and none have examined the relationships between oral to gut bacteria translocation, onset of dysbiosis, and systemic inflammation in HIV. We hypothesize that bacterial translocation from the mouth to the gut contributes to the development of dysbiosis in chronic HIV infection. Further, we hypothesize that the oral microbiome contributes to local and systemic inflammation in chronic HIV, and this altered mucosal environment may increase susceptibility for oral infections. Using longitudinal specimens, novel saliva analyses, and epidemiologic clinical outcomes we will systematically address our hypotheses. We propose to: 1) determine the contribution of oral microbiota to gut dysbiosis and systemic inflammation in persons living with HIV; 2) define the relationship between salivary IgA responses to key oral bacteria and local and systemic inflammation; and 3) identify specific oral bacteria that may predict risk of oral sexually transmitted infections (STI) in at-risk persons with and without HIV. This work will help better define the complex relationships between the oral microbiome, inflammation, and infection susceptibility in HIV; a critical step for developing novel strategies and saliva-based monitoring tools to better treat HIV and reduce comorbidities.

NIH Research Projects · FY 2025 · 2023-08

Project Summary/Abstract Physicians, who were previously told that it is medical malpractice to undertreat pain, are now told that they must avoid prescribing opioids whenever possible because of the risk of addiction. However, while analgesics such as nonsteroidal anti-inflammatory drugs are effective in relieving mild pain, they do not provide nearly the relief of severe pain that opioids do. Our recent work suggests that it may be possible to secure potent relief for severe pain with opioids, with a greatly reduced risk of addiction. In 2018 we reported that the brains of human heroin addicts had an average 54% increase in the number of “detectable” hypocretin (Hcrt=orexin) neurons and a 22% shrinkage of these neurons[1]. We found that these changes can outlast drug intake for at least 3 years. We further reported that similar changes in Hcrt neuron number and size could be induced by longterm daily administration of addictive doses of morphine to mice. We showed that these changes were not a result of neurogenesis, rather resulting from increased Hcrt synthesis in “Hcrt neurons” not producing detectable amounts of the Hcrt peptides at baseline. Subsequently, Aston-Jones's group reported a similar increase in the number of detectable Hcrt neurons in cocaine and fentanyl addicted rats, indicating that this is a correlate of several types of addiction. We had reported in 2000 that the loss of, on average, 90% of Hcrt neurons was the cause of human narcolepsy [2,3]. Narcoleptic humans have an extremely low rate of drug abuse, despite their prescribed daily use of addictive drugs, consistent with an important role for Hcrt in addiction. We find that morphine treated “narcoleptic” mice, in which Hcrt neurons had been selectively ablated, have greatly reduced naloxone triggered aversion, i.e. are “less addicted.” Recently we reported that chronic opioid administration greatly increases the projections of Hcrt neurons to locus coeruleus [4] and to the ventral tegmental area (Fig 5), regions linked to addiction. We now find that the addiction-associated changes in behavior and in Hcrt neuron number and size produced by morphine in mice are completely prevented by the dual Hcrt receptor antagonist suvorexant. Our pilot data indicates that the analgesic effect of morphine is not diminished by suvorexant. We will compare the effectiveness of suvorexant with Hcrt-R1 and Hcrt-R2 antagonists in reducing opiate induced changes in Hcrt neurons, and in reducing opiate anticipation and naloxone induced aversion. We will determine if Hcrt-R1 or Hcrt-R2 blockers affect morphine analgesia. We will determine the effect of Hcrt antagonists on the activity of Hcrt neurons after morphine and on opioid induced increases in Hcrt axonal projections, using quantitative confocal microscopy, electrical recording of unit activity and in vivo calcium imaging of Hcrt neurons. Our pilot data suggest that it may soon be possible to relieve severe pain with opioids without causing opioid addiction, thereby reducing the US opioid death toll, which now exceeds 76,000/year.