Medical Sciences Commons^™

Neurodevelopmental Abnormalities Underlying Behavioral Deficits In A Model Of Pediatric Obstructive Sleep Apnea, Arvind Chandrakantan, Michael R Williamson, Vaishnav Krishnan, Mahyar J Hedayatpour, Adam C Adler, Nandani Adyapak, Chris S Ward, Russell Ray, David Durgan, Farrah Kheradmand, Benjamin Deneen

Faculty, Staff and Students Publications

Rationale: Pediatric Obstructive Sleep Apnea (POSA) is a relatively common childhood sleep disorder whose neurodevelopmental phenotype includes deficits in learning and memory, olfaction, and fine motor abilities.

Objectives: To date, there has not been a validated preclinical model of POSA, hampering efforts in understanding how nocturnal episodes of intermittent hypoxia disrupt neurodevelopmental trajectories. The objective of this study was to create a faithful sculpting of the human condition in a preclinical murine model.

Methods: We used clinical data from children with POSA to develop and validate a mouse model of POSA that faithfully recapitulates several behavioral deficits seen in the …

Cd7 Regulates The Persistence Of Terminally Exhausted Cd8 T Cells During Chronic Infection, Sean Hyslop, Colby J Hofferek, Maria V Stegantseva, Emerald Kan, Kelli A Mccord, Victor M Alvarez, Amanda Y Xia, Jacob P Conarty, Andreas Wieland, William H Hudson

Faculty, Staff and Students Publications

CD8+ T cell exhaustion limits immune responses during cancer and chronic infection. We identify CD7 as a tissue-specific regulator of terminally exhausted CD8+ T cells during chronic infection. CD7 expression progressively increases during exhaustion, reaching its highest levels on a subset of CD101+Tim3low terminally exhausted cells that arise in the liver. Transcriptomic analysis revealed that CD7-deficient terminally exhausted cells display altered expression of co-stimulatory, translational, and effector genes, correlating with markedly reduced persistence and increased apoptotic susceptibility. Importantly, CD7 is preferentially upregulated on PD-1+CD39+ tumor-infiltrating lymphocytes (TILs) in human head and neck squamous cell carcinoma (HNSCC), suggesting CD7 may play …

Peritoneal Delivery Of Capsinoids, Nonpungent Trpv1 Agonists, Induces Mild Hypothermia In Conscious Mice Through Trpv1 Activation Of Visceral Vagal Afferents, Alexander P Andersohn, Ting Wu, Andrea N Doan, Charles L Cantrell, Robert L Jarret, Sean P Marrelli

Faculty, Staff and Student Publications

Therapeutic hypothermia (TH) has demonstrated neuroprotection in instances of cardiac arrest and neonatal hypoxia/ischemia but faces different challenges in application to stroke due to the activation of cold defense mechanisms in conscious patients. This study examined the efficacy and specificity of capsinoids (a purified mixture of capsiate and dihydrocapsiate) to induce a sustained fall in core body temperature in conscious mice. Capsinoids function as TRPV1 agonists. However, unlike capsaicin, capsinoids are vulnerable to esterase-mediated breakdown, thus significantly restricting their action to the site of delivery. We showed that capsinoids delivered intraperitoneally (IP) to mice induced a TRPV1-dependent drop in core …

Apoa1 Binding Protein Promotes Lymphatic Cell Fate And Lymphangiogenesis By Relieving Caveolae-Mediated Inhibition Of Vegfr3 Signaling, Jun-Dae Kim, Surbhi Chaudhary, Weiqing Chen, Jonathan Astin, Philip S Crosier, Pengchun Yu, John P Cooke, Henry J Pownall, Hugo J Bellen, Nhat-Tu Le, Daniel L Kiss, Guangyu Wang, Stanley G Rockson, Hong Chen, Longhou Fang

Faculty, Staff and Students Publications

The lymphatic system maintains tissue fluid balance, and its dysfunction can result in lymphedema. Although cholesterol is essential for cellular function, its role in lymphatic development has remained unknown. Here, we identify APOA1 binding protein (AIBP) as a key regulator that promotes lymphatic endothelial cell fate specification and lymphangiogenesis. Mechanistically, AIBP reduces plasma membrane cholesterol content, thereby enhancing VEGFR3 signaling by disrupting caveolae—small plasma membrane invaginations formed by the scaffolding protein caveolin-1 (CAV-1)—and relieving CAV-1–mediated inhibition. In zebrafish and mice, AIBP loss impairs VEGFR3 signaling and lymphatic development, defects that can be rescued by CAV-1 deletion or by a VEGFR3 …

Estrogen-Related Receptor Alpha Promotes Skeletal Muscle Regeneration And Mitigates Muscular Dystrophy, Thi Thu Hao Nguyen, Ya Xiang Huang, Svitlana Poliakova, Citu Citu, Eira Mann, Danesh H Sopariwala, Zhongming Zhao, Ashok Kumar, Vihang A Narkar

The Brown Foundation: Institute of Molecular Medicine

Skeletal muscle regeneration in chronic muscle diseases such as Duchenne Muscular Dystrophy (DMD) has remained clinically unsurmountable. Estrogen‐related receptor alpha (ERRα) plays a critical role in adult skeletal muscle metabolism and exercise fitness. Whether ERRα activation can drive muscle regeneration and mitigate dystrophy in DMD is not known. We have investigated ERRα signaling in pre‐clinical models of acute muscle injury and DMD. ERRα is induced in differentiating C2C12 myoblast and regenerating muscle. ERRα silencing suppressed proliferation and differentiation in C2C12 myoblasts. RNA sequencing revealed that angiogenic factor and proliferation genes were downregulated by ERRα knockdown in proliferating cells, whereas oxidative …

Genetics-Nutrition Interactions Control Diurnal Enhancer-Promoter Dynamics And Liver Lipid Metabolism, Dishu Zhou, Ying Chen, Panpan Liu, Kun Zhu, Juliet Holder-Haynes, S Julie-Ann Lloyd, Cam Mong La, Inna I Astapova, Seunghee Choa, Ying Xiong, Hosung Bae, Marlene Aguilar, Hongyuan Yang, Yu A An, Zheng Sun, Mark A Herman, Xia Gao, Liming Pei, Cholsoon Jang, Joshua D Rabinowitz, Samer G Mattar, Yongyou Zhang, Dongyin Guan

Faculty, Staff and Student Publications

The circadian clock controls 24-h rhythmic processes. However, how genetic variations outside clock genes impact peripheral diurnal rhythms remains largely unknown. Here, we find that genetic variation contributes to different diurnal patterns of hepatic gene expression in both humans and mice. Nutritional challenges alter the rhythmicity of gene expression in mouse liver in a strain-specific manner. Remarkably, genetics and nutrition interdependently control more than 80% of rhythmic gene and enhancer-promoter interactions (E-PIs), with a noncanonical clock regulator, estrogen-related receptor gamma (ESRRγ), emerging as a top transcription factor during motif mining. Knockout of Esrrγ abolishes strain-specific metabolic processes in response to …

Multicenter Stroke Preclinical Assessment Network Analysis Of Cardiovascular Risk Factor Subgroups Treated With The Poly(Adp-Ribose) Polymerase Inhibitor Veliparib, Raymond C Koehler, Karni Bedirian, Mu-Hsun Chen, Yanrong Shi, Suyi Cao, Brooklyn D Avery, Senthilkumar S Karuppagounder, Kazi Akhter, Adnan Bibic, Valina L Dawson, Ted M Dawson, Márcio A Diniz, Jessica Lamb, Karisma A Nagarkatti, Anjali Chauhan, Jaroslaw Aronowski, Louise D Mccullough, Andreia Lopes De Morais, Xuyan Jin, Cenk Ayata, Mariia Kumskova, Rakesh B Patel, Anil K Chauhan, Enrique C Leira, Pradip K Kamat, Mohammad B Khan, Krishnan M Dhandapani, David C Hess, Ligia S B Boisserand, Basavaraju G Sanganahalli, Lauren H Sansing, Patrick D Lyden

Faculty, Staff and Student Publications

Background: The Stroke Preclinical Assessment Network tested 6 therapeutic interventions initiated at the time of reperfusion after focal ischemic stroke in young mice, aging mice, obese mice, and spontaneously hypertensive rats. This randomized, controlled trial was conducted across 6 sites with concealed treatment and blinded neurobehavior assessments. The trial had an adaptive design with preset levels of efficacy and futility interrogated after each of 4 stages. The primary outcome was turning preference on the corner test at 1 month. The PARP (poly(ADP-ribose) polymerase) inhibitor, veliparib, was considered futile after the second stage when pooling all animal models (n=231 …

All-Optical Voltage Interrogation For Probing Synaptic Plasticity In Vivo, Jacques Carolan, Michelle A Land, Xiaoyu Lu, Maxime Beau, Dimitar Kostadinov, François St-Pierre, Beverley A Clark, Michael Häusser

Faculty, Staff and Students Publications

Measuring synaptic efficacy and defining the rules for induction of synaptic plasticity at identified connections in the mammalian brain is essential for understanding how synapses contribute to learning and memory. This requires new approaches to selectively evoke presynaptic activity and measure postsynaptic responses with high spatiotemporal resolution and high sensitivity over long periods in vivo. Here we develop an all-optical approach to probe synaptic plasticity at identified cerebellar synapses in awake, behaving mice. We developed and applied JEDI-2Psub, a genetically encoded voltage indicator with increased sensitivity around resting membrane potentials, to record subthreshold and suprathreshold activity in Purkinje cell (PC) …

Preclinical Models Of Melanoma Leptomeningeal Disease To Assess Intrathecal Checkpoint Blockade, Renato A Guerrieri, Grant M Fischer, Jacob R Cortez, Barbara G Knighton, Debora A Ledesma, Courtney W Hudgens, Yimmy F Delcid, Qianghua Hu, Christian Y B Onana, Fernando C L Carapeto, Michael T Tezlaff, Jason T Huse, Patrick Hwu, Elizabeth M Burton, Isabella C Glitza Oliva, Michael A Davies, Sherise D Ferguson

Faculty, Staff and Student Publications

Leptomeningeal disease (LMD) is a subtype of central nervous system metastatic disease that is associated with poor patient outcomes and limited treatment options. There is an unmet need to develop preclinical models of LMD to expedite and improve the development of new therapeutics. Here, we describe the development of multiple orthotopic immunocompetent murine models of melanoma LMD, including their use to assess the efficacy of systemic and/or intrathecal immunotherapy. LMD was established by direct intrathecal injection of murine cell lines (B16-F10, BP, D4M, D4M-UV2, MC38-gp100, RMS, YUMM3.1, and YUMMER1.7) into the cisterna magna of C57BL/6 mice. Tumor take rate, distribution, …

A Mast Cell Receptor Mediates Post-Stroke Brain Inflammation Via A Dural-Brain Axis, Ruchita Kothari, Mostafa W Abdulrahim, Hyun Jong Oh, Daniel H Capuzzi, Collin B Kilgore, Sumil K Nair, Yaowu Zhang, Nathachit Limjunyawong, Sarbjit S Saini, Jennifer E Kim, Justin M Caplan, Fernanado L Gonzalez, Christopher M Jackson, Chetan Bettegowda, Judy Huang, Bhanu P Ganesh, Chunfeng Tan, Raymond C Koehler, Rafael J Tamargo, Louise D Mccullough, Risheng Xu, Xinzhong Dong

Faculty, Staff and Student Publications

The immune environment surrounding the brain plays a fundamental role in monitoring signs of injury. Insults, including ischemic stroke, can disrupt this balance and incite an exaggerated inflammatory response, yet the underlying mechanism remains unclear. Here, we show that the mast-cell-specific receptor Mrgprb2 regulates post-stroke brain inflammation from the meninges. Mrgprb2 causes meningeal mast cell degranulation after stroke, releasing immune mediators. This process recruits skull bone marrow neutrophils into the dura and further promotes neutrophil migration from the dura into the brain by cleaving the chemorepellent semaphorin 3a. We demonstrate that the human ortholog, MRGPRX2, is expressed in human meningeal …

Escape Of Kdm6a From X Chromosome Is Detrimental To Ischemic Brains Via Irf5 Signaling, Conelius Ngwa, Afzal Misrani, Kanaka Valli Manyam, Yan Xu, Shaohua Qi, Romana Sharmeen, Juneyoung Lee, Long-Jun Wu, Louise Mccullough, Fudong Liu

The Brown Foundation: Institute of Molecular Medicine

The role of chromatin biology and epigenetics in disease progression is gaining increasing recognition. Genes that escape X chromosome inactivation (XCI) can impact neuroinflammation through epigenetic mechanisms. Our previous study has suggested that the X escapee genes Kdm6a and Kdm5c are involved in microglial activation after stroke in aged mice. However, the underlying mechanisms remain unclear. We hypothesized that Kdm6a/5c demethylate H3K27Me3/H3K4Me3 in microglia, respectively, and mediate the transcription of interferon regulatory factor 5 (IRF5) and IRF4, leading to microglial pro-inflammatory responses and exacerbated stroke injury. Aged (17–20 months) Kdm6a/5c microglial conditional knockout (CKO) female mice (one allele of the …

Tofacitinib Ameliorates Campylobacter-Induced Intestinal Pathology By Suppressing Ifnγ Producing Ilcs And T Cells, Anna A Korchagina, Sergey A Shein, Wayne T Muraoka, Justin Nguyen, Qiangxing Chen, Anna A Tumanova, Austin W Todd, Carlos E Rivera, Rita Tamayo, Paolo Casali, Ekaterina Koroleva, Alexei V Tumanov

Faculty, Staff and Student Publications

Patients with autoimmune diseases are more susceptible to foodborne infections, which can be exacerbated by immunosuppressive therapy. Tofacitinib, a JAK/STAT pathway inhibitor, was recently approved for the treatment of ulcerative colitis, yet its effects on the pathogenesis of intestinal infections remain unclear. Here, we examined the impact of oral tofacitinib treatment in a mouse model of Campylobacter jejuni (C. jejuni) infection. Our results show that early tofacitinib administration attenuates intestinal pathology without affecting bacterial colonization. Specifically, tofacitinib suppressed CXCL1, CXCL2, CCL2 chemokine expression by intestinal epithelial cells, limiting recruitment of monocytes and neutrophils to the gut. In addition, JAK/STAT inhibition …

Protein Kinase Rock1 Activates Mitochondrial Fission Linking To Oxidative Stress And Muscle Atrophy, Meijun Si, Jihong Chen, Rizhen Yu, Hongchun Lin, Feng Li, Sungyun Jung, Sandhya S Thomas, Farhard R Danesh, Yanlin Wang, Hui Peng, Zhaoyong Hu

Faculty, Staff and Students Publications

Introduction: Chronic kidney disease (CKD) is associated with protein-energy wasting, characterized by a reduction in muscle mass and strength. Although mitochondrial dysfunction and oxidative stress are implicated in the pathogenesis of muscle wasting, underlying mechanisms remain unclear.

Methods: Here, we used transcriptomic analysis, metabolomics analyses, and mouse gene manipulation to investigate the effects of mitochondrial plasticity and oxidative stress on muscle wasting the subtotal nephrectomy mouse models of CKD. The mice with CKD were age- and sex-matched to sham-operated controls.

Results: Through these approaches, Rho-associated kinase ROCK1 emerged as a key molecule responsible for the observed mitochondrial fission and oxidative …

Phosphorylation At Serine 214 Correlates With Tau Seeding Activity In An Age-Dependent Manner In Two Mouse Models For Tauopathies And Is Required For Tau Transsynaptic Propagation, Pablo Martinez, Nur Jury-Garfe, Henika Patel, Yanwen You, Abigail Perkins, Yingjian You, Audrey Lee-Gosselin, Ruben Vidal, Cristian A Lasagna-Reeves

Faculty, Staff and Students Publications

Background

Tau aggregation and propagation are hallmark features of Alzheimer's disease and related tauopathies. The molecular identity and post-translational modifications that contribute to tau seeding activity remain incompletely understood.

Objective

To characterize the temporal dynamics of tau seeding activity and identify specific phosphorylated tau species associated with tau propagation in vivo.

Methods

We profiled tau seeding activity using a FRET-based biosensor cell line and correlated it with the abundance of phospho- and conformational tau species in two transgenic mouse models of tauopathy (P301S-1N4R and P301S-0N4R). Immunohistochemistry and subcellular fractionation were used to examine the spatial distribution of tau species. Functional …

Exploring The Transformative Effects Of Calorie Restriction On The Lacrimal Gland In Adult Mice, Olivier Mauduit, Prashant Kumar, Kaitlin K Scholand, Emre Aksan, Laura Schaefer, Anmar Abu-Romman, Vanessa Delcroix, Zhiyuan Yu, Aude I Sindikubwabo, Ron Korstanje, Helen P Makarenkova, Cintia S De Paiva

Faculty, Staff and Students Publications

Advanced age is one of the most recognizable risk factors for dry eye. Dry eye disease affects millions worldwide and can result from age-related lacrimal gland dysfunction, which correlates with a decline in lacrimal gland secretory cell function and chronic inflammation. This study investigated the potential of calorie restriction to maintain lacrimal gland and ocular surface health. Adult female C57BL/6 J mice were subjected to a 40% calorie restriction for 4 months, starting at 6-7 months and continuing until 10-11 months. These mice were compared to controls fed ad libitum. Bulk RNA sequencing of lacrimal glands, conjunctiva, and cornea subjected …

Aging Affects Lipid Homeostasis In Lacrimal Glands By Upregulating Lipogenesis And Changing Its Specificity, Seher Yuksel, Prashant Kumar, Sydney E Krenz, Kaitlin K Scholand, Zhiyuan Yu, Anastasiia Ivanova, Helen P Makarenkova, Sarah F Hamm-Alvarez, Igor A Butovich, Cintia S De Paiva

Faculty, Staff and Students Publications

Purpose: The lacrimal gland (LG) develops age-related alterations. This study investigated the lipid content of the accumulated secretions within the murine aged LG.

Methods: C57BL/6J animals of different ages (3 months, 12 months, and 20-26 months) were used. Published data of bulk RNA sequencing of aged LGs were used to investigate lipid pathways. Exorbital LGs were excised for histology or PCR. Histologic sections were stained with standard histochemical stains or immunostained using anti-adiponectin, anti-perilipin 2 antibodies, and BODIPY dye. LG lipidomes were investigated using unbiased, untargeted high-resolution liquid chromatography/mass spectrometry (LC/MS), and the data were processed using unbiased, untargeted principal …

Lac-Phe Induces Hypophagia By Inhibiting Agrp Neurons In Mice, Hailan Liu, Veronica L Li, Qingzhuo Liu, Yao Liu, Cunjin Su, Hueyxian Wong, Na Yin, Hesong Liu, Xing Fang, Kristine M Mcdermott, Hueyzhong Wong, Meng Yu, Longlong Tu, Jonathan C Bean, Yongxiang Li, Mengjie Wang, Yue Deng, Yuhan Shi, Olivia Z Ginnard, Yuxue Yang, Junying Han, Megan E Burt, Sanika V Jossy, Chunmei Wang, Yongjie Yang, Benjamin R Arenkiel, Dong Kong, Yang He, Jonathan Z Long, Yong Xu

Faculty, Staff and Students Publications

Lactate-derived N-lactoyl-phenylalanine (Lac-Phe) was recently identified as an lactate-derived circulating metabolite that reduces feeding and obesity, but mechanisms that underlie the metabolic benefits of Lac-Phe remain unknown. Here we demonstrated that Lac-Phe directly inhibits hypothalamic neurons that express Agouti-related protein (AgRP), resulting in an indirect activation of anorexigenic neurons in the paraventricular nucleus of the hypothalamus (PVH). We also found that both AgRP inhibition and PVH activation are required to mediate Lac-Phe-induced hypophagia. Further, we show that Lac-Phe inhibits AgRP neurons via activating the ATP-sensitive potassium (KATP) channel, and inhibition of the KATP channel blunts effects of Lac-Phe to suppress …

Cyp1b1 Mediates Cigarette Smoke-Induced Lipid Accumulation In Alveolar Type 2 Cells, Yin Zhu, Siddhika Gamare, Francesca Polverino, Caroline A Owen, Payaningal R Somanath, Xiaoyun Wang, Duo Zhang

Faculty, Staff and Students Publications

Alterations in lipid profiles have been shown in patients with chronic obstructive pulmonary disease (COPD), but the underlying molecular mechanisms remain unclear. In this study, we aimed to investigate the role of cytochrome P450 family-1 subfamily B member 1 (CYP1B1) in cigarette smoke (CS)-induced lipid accumulation in alveolar type II epithelial (AT2) cells. We observed a steady increase in CYP1B1 protein levels in AT2 cells from COPD patients. Additionally, CS exposure induced CYP1B1 expression in AT2 cells of murine lungs. In vitro, treatment with cigarette smoke extract (CSE) not only upregulated CYP1B1 expression but also triggered lipid accumulation in AT2-like …

Aging In Mice Alters Regionally Enriched Striatal Astrocytes, Kay E Linker, Violeta Duran-Laforet, Matthias Ollivier, Xinzhu Yu, Dorothy P Schafer, Baljit S Khakh

Faculty, Staff and Student Publications

Aging affects multiple organs and within the brain drives distinct molecular changes across different cell types. The striatum encodes motor behaviors that decline with age, but our understanding of how cells within the striatum change remains incomplete. Using single-cell RNA sequencing from young and aged mice we identify molecularly distinct astrocyte subtypes. We show that astrocytes change significantly with age, exhibiting downregulation of genes, reduced diversity, and a shift to more homogenous inflammatory transcriptomic profiles. By exploring where striatal astrocyte subtypes are located with single-cell resolution, we map astrocytes enriched in dorsal, medial, and ventral striatum. Age increases inflammatory marker …

Protocol For Non-Invasive Pulsed-Doppler Evaluation Of Blood Flow In The Mouse Ophthalmic Artery, Radwa Awad, Emil Martin, Anilkumar K Reddy, Iraida Sharina

Faculty, Staff and Student Publications

The number of reliable and non-invasive techniques to characterize ocular blood flow is limited. Here, we present a protocol for identifying a soft tissue window in the orbital aperture using pulsed-Doppler ultrasonography to offer real-time, non-invasive blood flow velocity monitoring in the mouse ophthalmic artery. We describe steps for preparing a mouse, positioning the ultrasound probe, and acquiring and recording signals. We then detail procedures for analyzing results using a workstation equipped with Doppler flow velocity software. For complete details on the use and execution of this protocol, please refer to Sharina et al.

Sorting Nexin 3 Promotes Ischemic Retinopathy Through Rip1- And Rip3-Mediated Myeloid Cell Necroptosis And Mitochondrial Fission, Jiaojiao Wang, Chunhong Zhou, Kai Zhuang, Jiami Zou, Wanlu Qiu, Mei Jin, Weile Ye, Pinglian Yang, Zhihua Zheng, Qing Zhou, Zunnan Huang, Yuanxiang Wang, Peiqing Liu, Jing Lu, Yuqing Huo, Zhiping Liu

Faculty, Staff and Students Publications

Proliferative retinopathy is a leading cause of irreversible blindness in humans; however, the molecular mechanisms behind the immune cell–mediated retinal angiogenesis remain poorly elucidated. Here, using single-cell RNA sequencing in an oxygen-induced retinopathy (OIR) model, we identified an enrichment of sorting nexin (SNX)-related pathways, with SNX3, a member of the SNX family that is involved in endosomal sorting and trafficking, being significantly upregulated in the myeloid cell subpopulations of OIR retinas. Immunostaining showed that SNX3 expression is markedly increased in the retinal microglia/macrophages of mice with OIR, which is mainly located within and around the neovascular tufts. Myeloid cell-specific deficiency …

Retinoid-X-Receptor As A Mediator Of Poststroke Recovery By Reversing Age-Associated Phenotypes Of Microglia/Hematogenous Macrophages, Shun-Ming Ting, Xiurong Zhao, Guanghua Sun, Mercedes Ricote, Jaroslaw Aronowski

Faculty, Staff and Student Publications

After stroke, microglia and hematogenous macrophages, together referred to as MΦ, clear dead cells and cellular debris in the infarcted brain through phagocytosis as an essential part of the recovery process. However, the phagocytic capability of MΦ declines with age. Furthermore, aged MΦ become overactivated in response to stroke, enhancing secondary brain injury. In this study, we demonstrated that by reversing the age-related dysfunctions in MΦ through activating the retinoid X receptor (RXR), the recovery after stroke in the aged brain could be improved. Using RNA-sequencing, we compared the transcriptomes between MΦ isolated from the brains of young and aged …

Secretogranin 2 Binds Lilrb4 Resulting In Immunosuppression, Xing Yang, Ryan Huang, Meng Fang, Yubo He, Jingjing Xie, Xiaoye Liu, Chengcheng Zhang, Qi Lou, Mi Deng, Wei Xiong, Cheryl Lewis, Zade Sadek, Ankit Gupta, Lianqi Chen, Xuewu Zhang, Lei Guo, Lin Xu, Ningyan Zhang, Zhiqiang An, Cheng Cheng Zhang

Faculty, Staff and Student Publications

Immunosuppressive myeloid cells are important in a variety of physiological and pathological contexts, including tumor development, but how hormones might regulate their activity is unclear. Secretogranins, a family of secretory proteins in endocrine and neuronal cells, are proposed to function as prohormones or hormones, but their specific receptors are unknown. Here we show that secretogranin 2 (SCG2), a granin family member, functionally interacts with leukocyte immunoglobulin-like receptor B4 (LILRB4) on monocytic cells. Tumor-derived SCG2 promotes tumor growth in myeloid-specific LILRB4 transgenic mice in a T cell-dependent manner, whereas SCG2 deficiency in host mice impairs tumor progression and reduces infiltration of …

High-Speed Voltage Imaging Of Action Potentials In Molecular Layer Interneurons Reveals Sensory-Driven Synchrony That Augments Movement, Spencer T Brown, Meghana R Holla, Michelle A Land, Shuyuan Yang, Alex J Mcdonald, François St-Pierre, Indira M Raman

Faculty, Staff and Students Publications

Testing whether the synchrony of action potential firing is a cerebellar coding mechanism requires simultaneous recording, with high temporal fidelity, from populations of identified neurons. Here, we used targeted one-photon voltage imaging at 2–4 kHz to record action potentials from groups of ~10–300 molecular layer interneurons (MLIs) expressing a positively tuned, genetically encoded voltage indicator, FORCE1f or pAce. In awake resting mice, crus I MLIs fired brief (~1-ms) spikes at 20–60 spikes/s. Sensory stimuli of air puffs to the whiskers evoked short-latency (< 10 ms) increases in spiking probability. In most trials, >50% of MLIs fired synchronously with 4-ms temporal precision. The magnitude of puff-evoked whisks correlated tightly with …

Targeting Sting To Disrupt Macrophage-Mediated Adhesion In Encapsulating Peritoneal Sclerosis, Juan Sun, Yuxiang Sun, Dandan Guo, Huolin Ye, Qiang Huang, Hu Zhou, Canming Li, Mei Liao, Yujia You, Hongli Shang, Pan Zhou, Dongxuan Wu, Janusz Witowski, Zhaoyong Hu, Hui Peng

Faculty, Staff and Students Publications

Encapsulating peritoneal sclerosis (EPS) is a life-threatening fibrotic condition characterized by severe abdominal adhesions, chronic inflammation, and significant morbidity. The lack of effective treatments for EPS stems from a limited understanding of its underlying mechanisms. In this study, we developed a modified mouse model of PD-induced EPS and investigated the role of the STING signaling pathway in disease progression. Our findings reveal that STING activation in peritoneal mesothelial cells significantly increases the secretion of the macrophage chemokine CCL2, leading to enhanced macrophage infiltration and the formation of pathological adhesions. Notably, pharmacological inhibition of STING using the inhibitor H151 effectively reduced …

Prolonged Exposure To Food Odors Suppresses Feeding Via An Olfactory Bulb-To-Hypothalamus Circuit, Yao Liu, Hailan Liu, Huey-Xian Kelly Wong, Niccole Auld, Kristine M Conde, Yongxiang Li, Meng Yu, Yue Deng, Qingzhuo Liu, Xing Fang, Mengjie Wang, Yuhan Shi, Olivia Z Ginnard, Yuxue Yang, Longlong Tu, Hesong Liu, Jonathan C Bean, Junying Han, Megan E Burt, Sanika V Jossy, Yongjie Yang, Chunmei Wang, Qingchun Tong, Benjamin R Arenkiel, Hongjie Li, Yong Xu, Yang He

The Brown Foundation: Institute of Molecular Medicine

Olfactory perception of food odors is a key determinant of eating behavior, including triggering appetite, facilitating food seeking and influencing food choice. While transient food-related olfactory cues stimulate appetite and provoke cravings in states of hunger, emerging evidence implies that prolonged and sustained exposure to food-derived odor (FO) suppresses feeding. However, the mechanisms by which olfaction induces hypophagia remain elusive. In this study, we show that prolonged FO exposure significantly suppresses food intake in male mice. We identified a subset of neurons in the ventral subiculum (vSub) that are specifically activated by FO. We further discovered that these FO-activated neurons …

Prefrontal Cortex Astrocytes Modulate Distinct Neuronal Populations To Control Anxiety-Like Behavior, Eunyoung Kim, Hairuo Du, Yanqi Tan, Brandon L Brown, Yaowen Chang, Blanca Díaz-Castro, Jonathan V Sweedler, Xinzhu Yu

Faculty, Staff and Student Publications

Accumulating evidence has supported diverse regulatory functions of astrocytes in different neural circuits as well as various aspects of complex behaviors. However, little is known about how astrocytes regulate different neuronal subpopulations that are linked to specific behavioral aspects within a single brain region. Here, we show that astrocytes in the medial prefrontal cortex (mPFC) encode anxiogenic environmental cues in freely behaving mice. Silencing mPFC astrocyte Ca

Highly Oligomeric Drp1 Strategic Positioning At Mitochondria-Sarcoplasmic Reticulum Contacts In Adult Murine Heart Through Actin Anchoring, Celia Fernandez-Sanz, Sergio De La Fuente, Zuzana Nichtova, Marilen Federico, Stephane Duvezin-Caubet, Sebastian Lanvermann, Hui-Ying Tsai, Yanguo Xin, György Csordás, Wang Wang, Arnaud Mourier, Shey-Shing Sheu

Department of Medicine Faculty Papers

Mitochondrial fission and fusion appear to be relatively infrequent in cardiac cells compared to other cell types; however, the proteins involved in these events are highly expressed in adult cardiomyocytes (ACM). Therefore, these proteins likely have additional non-canonical roles. We have previously shown that DRP1 not only participates in mitochondrial fission processes but also regulates mitochondrial bioenergetics in cardiac tissue. However, it is still unknown where the DRP1 that does not participate in mitochondrial fission is located and what its role is at those non-fission spots. Therefore, this manuscript will clarify whether oligomeric DRP1 is located at the SR–mitochondria interface, …

Regional Heterogeneity Of The Blood-Brain Barrier, Marie Blanchette, Kaja Bajc, Benjamin D Gastfriend, Caterina P Profaci, Nadine Ruderisch, Cayce E Dorrier, Guo Zhong, Raquel Cuevas-Diaz Duran, Sean S Harvey, Iris H Garcia-Pak, Lucija Pintarić, Manon Leclerc, Louise Reveret, Vincent Émond, Annette Wang, Deepti Pant, Linus T Tsai, Frédéric Calon, Nina Isoherranen, Sean P Palecek, Eric V Shusta, Jiaqian Wu, Richard Daneman

The Brown Foundation: Institute of Molecular Medicine

The blood-brain barrier (BBB), formed by specialized endothelial cells (ECs), regulates the extracellular composition of the central nervous system (CNS). Little is known about whether there are regional specializations of the BBB that may control the function of specific neural circuits. We use single cell RNA-seq to characterize ECs from nine CNS regions in male mice: cortex, hippocampus, cerebellum, spinal cord, striatum, thalamus, hypothalamus, midbrain, and medulla/pons. Although there is a core BBB transcriptional profile, there are significant regional specializations. Stra6, a retinoid transporter, is highly enriched in the BBB of the nucleus accumbens shell (ShNAc) and ventral cochlear nucleus, …

Tet2-Mutant Myeloid Cells Mitigate Alzheimer’S Disease Progression Via Cns Infiltration And Enhanced Phagocytosis In Mice, Katie A Matatall, Trisha K Wathan, Minh Nguyen, Hu Chen, Alexandra Mcdonald, Guantong Qi, Julia A Belk, Marcus A Florez, Duy T Le, Temitope Olarinde, Caitlyn Vlasschaert, Marco M Buttigieg, Chih-Wei Fan, Saul Carcamo, Ruoqiong Cao, Daniel E Kennedy, Arushana A Maknojia, Apoorva Thatavarty, Josaura V Fernandez Sanchez, Hind Bouzid, Surabi Veeraragavan, Susan Crocker, Margaret A Goodell, Antony Rodriguez, Siddhartha Jaiswal, Michael J Rauh, Eirini P Papapetrou, Samuele G Marro, Katherine Y King

Faculty, Staff and Students Publications

Clonal hematopoiesis (CH) is associated with many age-related diseases, but its interaction with Alzheimer's disease (AD) remains unclear. Here, we show that TET2-mutant CH is associated with a 47% reduced risk of late-onset AD (LOAD) in the UK Biobank, whereas other drivers of CH do not confer protection. In a mouse model of AD, transplantation of Tet2-mutant bone marrow reduced cognitive decline and β-amyloid plaque formation, effects not observed with Dnmt3a-mutant marrow. Bone-marrow-derived microglia-like cells were detected at an increased rate in Tet2-mutant marrow recipients, and TET2-mutant human induced pluripotent stem cell (iPSC)-derived microglia were more phagocytic and hyperinflammatory than …