Endocrinology, Diabetes, and Metabolism Commons^™

Haploinsufficiency Of Itsn1 Is Associated With A Substantial Increased Risk Of Parkinson’S Disease, Thomas P Spargo, Chloe F Sands, Isabella R Juan, Jonathan Mitchell, Vida Ravanmehr, Jessica C Butts, Ruth B De-Paula, Youngdoo Kim, Fengyuan Hu, Quanli Wang, Dimitrios Vitsios, Manik Garg, Lawrence Middleton, Michal Tyrlik, Mirko Messa, Guillermo Del Angel, Daniel G Calame, Hiba Saade, Laurie Robak, Ben Hollis, Vishnu A Cuddapah, Huda Y Zoghbi, Joshua M Shulman, Slavé Petrovski, Ismael Al-Ramahi, Ioanna Tachmazidou, Ryan S Dhindsa

Faculty, Staff and Students Publications

Despite its significant heritability, the genetic basis of Parkinson's disease (PD) remains incompletely understood. Here, in analyzing whole-genome sequence data from 3,809 PD cases and 247,101 controls in the UK Biobank, we discover that protein-truncating variants in ITSN1 confer a substantially increased risk of PD (p = 6.1 × 10

Adipose Progenitor Cell-Derived Extracellular Vesicles Suppress Macrophage M1 Program To Alleviate Midlife Obesity, Qing Zhou, Jia Gao, Guorao Wu, Chenwei Wang, Yan Yang, Teng Huang, Yi Wang, Tiantian Yue, Zhichao Gao, Hao Xie, Fei Xiong, Ke Xiang, Tuying Yong, Wanguang Zhang, Tongtong Zhang, Wen Kong, Cai Chen, Shu Zhang, Qilin Yu, Xuemei Fan, Shiwei Liu, Yanjun Liu, Cong-Yi Wang

Children’s Nutrition Research Center Staff Publications

Among different age groups, middle-aged individuals are particularly susceptible to obesity, with a 22% higher risk of all-cause mortality. However, the underlying mechanisms remain unclear. In this study, we identify adipose progenitor cells (APCs) in the white adipose tissue (WAT) of middle-aged subjects as potential causes of midlife obesity. Specifically, the extracellular vesicles (EVs) derived from APCs display an impaired ability to mitigate the inflammaging of adipose tissue macrophages (ATMs) in middle-aged individuals. Mechanistically, these EVs, lacking miR-145-5p, fail to suppress the expression of L-selectin in ATMs, thereby facilitating their M1 program via the NF-κB signaling pathway. In contrast, EVs …

Regulating Chemoresistance And Cancer Stemness: The Cdh17-Yap Pathway In Distinct Cellular States Of Lung Cancer Ctc Clusters, Zujun Que, Dan Qi, Yun Yang, Wang Yao, Jiajun Liu, Yan Li, Yuanyuan Yu, Luyao Wang, Fangfei Li, Ge Zhang, Erxi Wu, Jianhui Tian

Children’s Nutrition Research Center Staff Publications

Background: Drug resistance in metastatic lung cancer significantly contributes to patient mortality. This study explores the role of circulating tumor cells (CTCs), the precursors to metastasis, in driving this resistance. We aim to delineate the unique biological traits of CTC clusters in lung cancer and elucidate the mechanisms underlying their resistance to chemotherapy.

Methods: We used an ultralow adsorption plate to establish a CTC suspension culture system. Comparisons between adherent and suspension cultures of CTC-TJH-01 cells were made via Cell Counting Kit-8 (CCK-8), western blot, immunofluorescence, and flow cytometry assays to evaluate cell proliferation, drug resistance, and cancer stemness. The …

Biguanides Antithetically Regulate Tumor Properties By The Dose-Dependent Mitochondrial Reprogramming-Driven C-Src Pathway, Jun Hyoung Park, Kwang Hwa Jung, Dongya Jia, Sukjin Yang, Kuldeep S Attri, Songyeon Ahn, Divya Murthy, Tagari Samanta, Debasmita Dutta, Meron Ghidey, Somik Chatterjee, Seung Yeop Han, Diego A Pedroza, Abha Tiwari, Joyce V Lee, Caitlin Davis, Shuting Li, Vasanta Putluri, Chad J Creighton, Nagireddy Putluri, Lacey E Dobrolecki, Michael T Lewis, Jeffrey M Rosen, José N Onuchic, Andrei Goga, Benny Abraham Kaipparettu

Faculty, Staff and Students Publications

The biguanide metformin attenuates mitochondrial oxidation and is proposed as an anti-cancer therapy. However, recent clinical studies suggest increased proliferation and fatty acid β-oxidation (FAO) in a subgroup of patients with breast cancer (BC) after metformin therapy. Considering that FAO can activate Src kinase in aggressive triple-negative BC (TNBC), we postulate that low-dose biguanide-driven AMPK-ACC-FAO signaling may activate the Src pathway in TNBC. The low bioavailability of metformin in TNBC xenografts mimics metformin's in vitro low-dose effect. Pharmacological or genetic inhibition of FAO significantly enhances the anti-tumor properties of biguanides. Lower doses of biguanides induce and higher doses suppress Src …

Leptin Receptor Neurons In The Dorsomedial Hypothalamus Require Distinct Neuronal Subsets For Thermogenesis And Weight Loss, Marie Francois, Laura Kaiser, Yanlin He, Yong Xu, J Michael Salbaum, Sangho Yu, Christopher D Morrison, Hans-Rudolf Berthoud, Heike Münzberg

Children’s Nutrition Research Center Staff Publications

The dorsomedial hypothalamus (DMH) receives inputs from the preoptic area (POA), where ambient temperature mediates physiological adaptations of energy expenditure and food intake. Warm-activated POA neurons suppress energy expenditure via brown adipose tissue (BAT) projecting neurons in the dorsomedial hypothalamus/dorsal hypothalamic area (dDMH/DHA). Our earlier work identified leptin receptor (Lepr)-expressing, BAT-projecting dDMH/DHA neurons that mediate metabolic leptin effects. Yet, the neurotransmitter (glutamate or GABA) used by dDMH/DHALepr neurons remains unexplored and was investigated in this study using mice. We report that dDMH/DHALepr neurons represent equally glutamatergic and GABAergic neurons. Surprisingly, chemogenetic activation of glutamatergic and/or GABAergic dDMH/DHA neurons were capable …

Serotonin Neurons Integrate Gaba And Dopamine Inputs To Regulate Meal Initiation, Kristine M Conde, Hueyzhong Wong, Shuzheng Fang, Yongxiang Li, Meng Yu, Yue Deng, Qingzhuo Liu, Xing Fang, Mengjie Wang, Yuhan Shi, Olivia Z Ginnard, Yuxue Yang, Longlong Tu, Hesong Liu, Hailan Liu, Na Yin, Jonathan C Bean, Junying Han, Megan E Burt, Sanika V Jossy, Yongjie Yang, Qingchun Tong, Benjamin R Arenkiel, Chunmei Wang, Yang He, Yong Xu

Children’s Nutrition Research Center Staff Publications

Obesity is a growing global health epidemic with limited orally administered therapeutics. Serotonin (5-HT) is one neurotransmitter which remains an excellent target for new weight-loss therapies, but a gap remains in understanding the mechanisms involved in 5-HT produced in the dorsal Raphe nucleus (DRN) and its involvement in meal initiation. Using an optogenetic feeding paradigm, we showed that the 5-HTDRN→arcuate nucleus (ARH) circuit plays a role in meal initiation. Incorporating electrophysiology and ChannelRhodopsin-2-Assisted Circuit Mapping, we demonstrated that 5-HTDRN neurons receive inhibitory input partially from GABAergic neurons in the DRN, and the 5-HT response can be enhanced by hunger. Additionally, …

Spock2 Controls The Proliferation And Function Of Immature Pancreatic Β-Cells Through Mmp2, Katarzyna Blaszczyk, Anna P Jedrzejak, Natalia Ziojla, Ekaterina Shcheglova, Karolina Szarafin, Artur Jankowski, Christine A Beamish, Jolanta Chmielowiec, Omaima M Sabek, Ashok Balasubramanyam, Sanjeet Patel, Malgorzata Borowiak

Faculty, Staff and Students Publications

Human pluripotent stem cell-derived β-cells (SC-β-cells) represent an alternative cell source for transplantation in diabetic patients. Although mitogens could in theory be used to expand β-cells, adult β-cells very rarely replicate. In contrast, newly formed β-cells, including SC-β-cells, display higher proliferative capacity and distinct transcriptional and functional profiles. Through bidirectional expression modulation and single-cell RNA-seq, we identified SPOCK2, an ECM protein, as an inhibitor of immature β-cell proliferation. Human β-cells lacking SPOCK2 presented elevated MMP2 expression and activity, leading to β-integrin-FAK-c-JUN pathway activation. Treatment with the MMP2 protein resulted in pronounced short- and long-term SC-β-cell expansion, significantly increasing glucose-stimulated insulin …

A Β-Hydroxybutyrate Shunt Pathway Generates Anti-Obesity Ketone Metabolites, Maria Dolores Moya-Garzon, Mengjie Wang, Veronica L Li, Xuchao Lyu, Wei Wei, Alan Sheng-Hwa Tung, Steffen H Raun, Meng Zhao, Laetitia Coassolo, Hashim Islam, Barbara Oliveira, Yuqin Dai, Jan Spaas, Antonio Delgado-Gonzalez, Kenyi Donoso, Aurora Alvarez-Buylla, Francisco Franco-Montalban, Anudari Letian, Catherine P Ward, Lichao Liu, Katrin J Svensson, Emily L Goldberg, Christopher D Gardner, Jonathan P Little, Steven M Banik, Yong Xu, Jonathan Z Long

Children’s Nutrition Research Center Staff Publications

β-Hydroxybutyrate (BHB) is an abundant ketone body. To date, all known pathways of BHB metabolism involve the interconversion of BHB and primary energy intermediates. Here, we identify a previously undescribed BHB secondary metabolic pathway via CNDP2-dependent enzymatic conjugation of BHB and free amino acids. This BHB shunt pathway generates a family of anti-obesity ketone metabolites, the BHB-amino acids. Genetic ablation of CNDP2 in mice eliminates tissue amino acid BHB-ylation activity and reduces BHB-amino acid levels. The most abundant BHB-amino acid, BHB-Phe, is a ketosis-inducible congener of Lac-Phe that activates hypothalamic and brainstem neurons and suppresses feeding. Conversely, CNDP2-KO mice exhibit …

Novel Insights Into Beta Cell Er Stress Chop And It's Role In Hfpef Development, Balaji Srinivas, Paula Fortuno, Hongmei Peng, Jiang Xu, Hamid Suhail, Hani N. Sabbah, Nour-Eddine Rhaleb, Khalid Matrougui

Department of Physiological Sciences Faculty Publications

Introduction: Heart failure with preserved ejection fraction (HFpEF) is a multifactorial cardiovascular disorder characterized by diastolic dysfunction and often associated with hypertension and metabolic disturbances. We aimed to determine the inter-relationship between C/EBP homologous protein (CHOP) in b-cells and HFpEF development.

Methods: Eight-week-old male mice b-cell^flox/flox and b-cell^CHOP-/- were randomly divided into four groups: control b-cell^flox/flox and b-cell^CHOP-/- mice subjected to standard diet and water. b -cell^flox/flox and b-cell^CHOP-/- mice fed a high-fat diet (HFD) and L-NAME (0.5 g/L) for five weeks. A comprehensive cardiovascular, metabolic, and histological evaluation was conducted.

Results: Following …

New Genetic Tools To Define The Pathophysiology Of Inborn Errors Of Cobalamin Metabolism Impacting Mammalian Development, Tiffany Chern, Xuefei Tong, William G Bauer, David J Quispe-Parra, Xia Gao, Kamryn N Gerner-Mauro, Ross A Poché

Children’s Nutrition Research Center Staff Publications

The congenital, autosomal recessive disorder combined methylmalonic acidemia and homocystinuria - cblC type, is the most common inborn error of cobalamin (vitamin B12) metabolism. In its early onset form, cblC profoundly impacts fetal development of the central nervous system, hematopoietic system, and other tissues. Previously, mutations in the MMACHC gene, which encodes a protein required for the intracellular trafficking and enzymatic processing of free cobalamin into active coenzyme forms, were found to cause cblC. These coenzymes are required in two metabolic pathways which produce either succinyl-CoA in the mitochondria or methionine in the cytosol. However, due to a lack of …

Ephb4-Rasa1 Inhibition Of Piezo1 Ras Activation Drives Lymphatic Valvulogenesis, Di Chen, Yipei Tang, Philip E Lapinski, David Wiggins, Eva M Sevick, Michael J Davis, Philip D King

Faculty, Staff and Student Publications

BACKGROUND: EPHB4 (ephrin receptor B4) and the RASA1 (p120 Ras GTPase-activating protein) are necessary for the development of lymphatic vessel (LV) valves. However, precisely how EPHB4 and RASA1 regulate LV valve development is unknown. In this study, we examine the mechanisms by which EPHB4 and RASA1 regulate the development of LV valves.

METHODS: We used LV-specific inducible EPHB4-deficient mice and EPHB4 knockin mice that express a form of EPHB4 that is unable to bind RASA1 yet retains protein tyrosine kinase activity (EPHB4 2YP) to study the role of EPHB4 and RASA1 in LV valve development in the embryo and LV …

Transcriptomic And Epigenomic Signatures Distinguish High- And Low-Risk Endotypes For Liver Tumor Development, Sandra L Grimm, Tia Talley, Rahul K Jangid, Amrit Koirala, Micah B Castillo, Preethi H Gunaratne, Cristian Coarfa, Cheryl L Walker

Faculty, Staff and Students Publications

The epigenome is a target for environmental exposures and a potential determinant of inter-individual differences in response. In genetically identical C57Bl/6 mice exposed from gestation to weaning to the endocrine-disrupting chemical (EDC) tributyltin (TBT), hepatic tumor development later in life varied across multiple cohorts over time and depending on sex and diet. In one cohort where approximately half of TBT-exposed male mice developed liver tumors at 10 months (Katz et al. Hepatic tumor formation in adult mice developmentally exposed to organotin, Environmental Health Perspectives, 128 (1), 17010, 2020), transcriptomic (RNA-seq) and epigenomic (ChIP-seq) profiling was performed on blood and liver …

Biallelic Loss-Of-Function Variants In Ubap1l And Nonsyndromic Retinal Dystrophies, Ehsan Ullah, Siying Lin, Jiaxiong Lu, Chelsea Bender, Andrew R Webster, Samantha Malka, Savita Madhusudhan, Emma Rees, Denise Williams, Aime R Agather, Catherine A Cukras, Robert B Hufnagel, Rui Chen, Laryssa A Huryn, Gavin Arno, Bin Guan

Faculty, Staff and Students Publications

Importance: Inherited retinal dystrophies (IRDs) present a challenge in clinical diagnostics due to their pronounced genetic heterogeneity. Despite advances in next-generation sequencing (NGS) technologies, a substantial portion of the genetic basis underlying IRDs remains elusive. Addressing this gap seems important for gaining insights into the genetic landscape of IRDs, which may help improve diagnosis and prognosis and develop targeted therapies in the future.

Objective: To provide a clinical and molecular characterization of 6 patients with IRDs with biallelic disease-causing variants in a novel candidate IRD disease gene.

Design, setting, and participants: This multicenter case series study included 6 patients with …

Reproduction Has Immediate Effects On Female Mortality, But No Discernible Lasting Physiological Impacts: A Test Of The Disposable Soma Theory, Sharon E Mitchell, Megan Simpson, Lena Coulet, Solenn Gouedard, Catherine Hambly, Juliano Morimoto, David B Allison, John R Speakman

Children’s Nutrition Research Center Staff Publications

The disposable soma theory (DST) posits that organisms age and die because of a direct trade-off in resource allocation between reproduction and somatic maintenance. DST predicts that investments in reproduction accentuate somatic damage which increase senescence and shortens lifespan. Here, we directly tested DST predictions in breeding and nonbreeding female C57BL/6J mice. We measured reproductive outputs, body composition, daily energy expenditure, and oxidative stress at peak lactation and over lifetime. We found that reproduction had an immediate and negative effect on survival due to problems encountered during parturition for some females. However, there was no statistically significant residual effect on …

Tca Metabolism Regulates Dna Hypermethylation In Lps And Mycobacterium Tuberculosis–Induced Immune Tolerance, Abhimanyu, Santiago Carrero Longlax, Tomoki Nishiguchi, Malik Ladki, Daanish Sheikh, Amera L Martinez, Emily M Mace, Sandra L Grimm, Thaleia Caldwell, Alexandra Portillo Varela, Rajagopal V Sekhar, Anna M Mandalakas, Mandla Mlotshwa, Sibuse Ginidza, Jeffrey D Cirillo, Robert S Wallis, Mihai G Netea, Reinout Van Crevel, Cristian Coarfa, Andrew R Dinardo

Faculty, Staff and Students Publications

Severe and chronic infections, including pneumonia, sepsis, and tuberculosis (TB), induce long-lasting epigenetic changes that are associated with an increase in all-cause postinfectious morbidity and mortality. Oncology studies identified metabolic drivers of the epigenetic landscape, with the tricarboxylic acid (TCA) cycle acting as a central hub. It is unknown if the TCA cycle also regulates epigenetics, specifically DNA methylation, after infection-induced immune tolerance. The following studies demonstrate that lipopolysaccharide and Mycobacterium tuberculosis induce changes in DNA methylation that are mediated by the TCA cycle. Infection-induced DNA hypermethylation is mitigated by inhibitors of cellular metabolism (rapamycin, everolimus, metformin) and the TCA …

Benefits Of Calorie Restriction In Mice Are Mediated Via Energy Imbalance, Not Absolute Energy Or Protein Intake, Daniel L Smith, Sharon E Mitchell, Maria S Johnson, Victoria K Gibbs, Stephanie Dickinson, Beate Henschel, Rui Li, Kathryn A Kaiser, Daniella E Chusyd, Andrew W Brown, David B Allison, John R Speakman, Tim R Nagy

Children’s Nutrition Research Center Staff Publications

Caloric restriction (CR) results in reduced energy and protein intake, raising questions about protein restriction's contribution to CR longevity benefits. We kept ad libitum (AL)-fed male C57BL/6J mice at 27°C (AL27) and pair-fed (PF) mice at 22°C (22(PF27)). The 22(PF27) group was fed to match AL27 while restricted for calories due to cold-induced metabolism. The 22(PF27) mice had significantly lower body weight, lean mass, fat mass, leptin, IGF-1, and TNF-α levels than AL27 mice (p< 0.001 for all). Manipulations over ~11 weeks resulted in significant differences in body temperature, physical activity, and expression of key genes linked to hunger in the hypothalamus. Survival was significantly greater in 22(PF27) compared to AL27 overall (p< 0.001). CR in the context of equivalent energy and protein intake resulted in hormonal, metabolic, and physiological benefits and extended longevity. Hence, energy imbalance, rather than low energy or protein intake per se, mediates the benefits of CR.

Il-22 Resolves Masld Via Enterocyte Stat3 Restoration Of Diet-Perturbed Intestinal Homeostasis, Peng Zhang, Junlai Liu, Allen Lee, Irene Tsaur, Masafumi Ohira, Vivian Duong, Nicholas Vo, Kosuke Watari, Hua Su, Ju Youn Kim, Li Gu, Mandy Zhu, Shabnam Shalapour, Mojgan Hosseini, Gautam Bandyopadhyay, Suling Zeng, Cristina Llorente, Haoqi Nina Zhao, Santosh Lamichhane, Siddharth Mohan, Pieter C Dorrestein, Jerrold M Olefsky, Bernd Schnabl, Pejman Soroosh, Michael Karin

Faculty, Staff and Student Publications

The exponential rise in metabolic dysfunction-associated steatotic liver disease (MASLD) parallels the ever-increasing consumption of energy-dense diets, underscoring the need for effective MASLD-resolving drugs. MASLD pathogenesis is linked to obesity, diabetes, "gut-liver axis" alterations, and defective interleukin-22 (IL-22) signaling. Although barrier-protective IL-22 blunts diet-induced metabolic alterations, inhibits lipid intake, and reverses microbial dysbiosis, obesogenic diets rapidly suppress its production by small intestine-localized innate lymphocytes. This results in STAT3 inhibition in intestinal epithelial cells (IECs) and expansion of the absorptive enterocyte compartment. These MASLD-sustaining aberrations were reversed by administration of recombinant IL-22, which resolved hepatosteatosis, inflammation, fibrosis, and insulin resistance. Exogenous …

Impact Of Essential Genes On The Success Of Genome Editing Experiments Generating 3313 New Genetically Engineered Mouse Lines, Hillary Elrick, Kevin A Peterson, Brandon J Willis, Denise G Lanza, Elif F Acar, Edward J Ryder, Lydia Teboul, Petr Kasparek, Marie-Christine Birling, David J Adams, Allan Bradley, Robert E Braun, Steve D Brown, Adam Caulder, Gemma F Codner, Francesco J Demayo, Mary E Dickinson, Brendan Doe, Graham Duddy, Marina Gertsenstein, Leslie O Goodwin, Yann Hérault, Lauri G Lintott, K C Kent Lloyd, Isabel Lorenzo, Matthew Mackenzie, Ann-Marie Mallon, Colin Mckerlie, Helen Parkinson, Ramiro Ramirez-Solis, John R Seavitt, Radislav Sedlacek, William C Skarnes, Damien Smedley, Sara Wells, Jacqueline K White, Joshua A Wood, International Mouse Phenotyping Consortium, Stephen A Murray, Jason D Heaney, Lauryl M J Nutter

Faculty, Staff and Students Publications

The International Mouse Phenotyping Consortium (IMPC) systematically produces and phenotypes mouse lines with presumptive null mutations to provide insight into gene function. The IMPC now uses the programmable RNA-guided nuclease Cas9 for its increased capacity and flexibility to efficiently generate null alleles in the C57BL/6N strain. In addition to being a valuable novel and accessible research resource, the production of 3313 knockout mouse lines using comparable protocols provides a rich dataset to analyze experimental and biological variables affecting in vivo gene engineering with Cas9. Mouse line production has two critical steps - generation of founders with the desired allele and …

Dense And Persistent Odor Representations In The Olfactory Bulb Of Awake Mice, Delaram Pirhayati, Cameron L Smith, Ryan Kroeger, Saket Navlakha, Paul Pfaffinger, Jacob Reimer, Benjamin R Arenkiel, Ankit Patel, Elizabeth H Moss

Children’s Nutrition Research Center Staff Publications

Recording and analysis of neural activity are often biased toward detecting sparse subsets of highly active neurons, masking important signals carried in low-magnitude and variable responses. To investigate the contribution of seemingly noisy activity to odor encoding, we used mesoscale calcium imaging from mice of both sexes to record odor responses from the dorsal surface of bilateral olfactory bulbs (OBs). The outer layer of the mouse OB is comprised of dendrites organized into discrete "glomeruli," which are defined by odor receptor-specific sensory neuron input. We extracted activity from a large population of glomeruli and used logistic regression to classify odors …

Small Gtp-Binding Protein Gdp Dissociation Stimulator Influences Cisplatin-Induced Acute Kidney Injury Via Perk-Dependent Er Stress, Yuxue Yang, Ting Xiong, Ti Wang, Xiwei Chen, Ziwei Ma, Bangyun Zuo, Dong Ning, Ruilong Song, Xuesong Liu, Daxin Wang

Children’s Nutrition Research Center Staff Publications

Cisplatin is a common anticancer drug, but its frequent nephrotoxicity limits its clinical use. Small GTP-binding protein GDP dissociation stimulator (smgGDS), a small GTPase chaperone protein, was considerably downregulated during cisplatin-induced acute kidney injury (CDDP-AKI), especially in renal tubular epithelial cells. SmgGDS-knockdown mice was established and found that smgGDS knockdown promoted CDDP-AKI, as demonstrated by an increase in serum creatine, blood urea nitrogen levels and the appearance of tubular patterns. RNA sequencing suggested that protein kinase RNA-like ER kinase (PERK), which bridges mitochondria-associated ER membranes, was involved in smgGDS knockdown following CDDP-AKI, and then identified that smgGDS knockdown increased phosphorylated-PERK …

Mechanistic Insights Into Metabolic Function Of Dynamin-Related Protein 1, Xin Li, Katherine Pham, Jazmin Ysaguirre, Iqbal Mahmud, Lin Tan, Bo Wei, Long J Shao, Maryam Elizondo, Rabie Habib, Fathima Elizondo, Hiromi Sesaki, Philip L Lorenzi, Kai Sun

Faculty, Staff and Student Publications

Dynamin-related protein 1 (DRP1) plays crucial roles in mitochondrial and peroxisome fission. However, the mechanisms underlying the functional regulation of DRP1 in adipose tissue during obesity remain unclear. To elucidate the metabolic and pathological significance of diminished DRP1 in obese adipose tissue, we utilized adipose tissue-specific DRP1 KO mice challenged with a high-fat diet. We observed significant metabolic dysregulations in the KO mice. Mechanistically, DRP1 exerts multifaceted functions in mitochondrial dynamics and endoplasmic reticulum (ER)-lipid droplet crosstalk in normal mice. Loss of function of DRP1 resulted in abnormally giant mitochondrial shapes, distorted mitochondrial membrane structure, and disrupted cristae architecture. Meanwhile, …

Not Feeling The Heat? Effects Of Dietary Protein On Satiation And Satiety In Mice Are Not Due To Its Impact On Body Temperature, Jazmin Osorio M, Sharon E Mitchell, Catherine Hambly, David B Allison, John R Speakman

Children’s Nutrition Research Center Staff Publications

Dietary protein modulates food intake (FI) via unclear mechanism(s). One possibility is that higher protein leads to greater post-ingestive heat production (Specific dynamic action: SDA) leading to earlier meal termination (increased satiation), and inhibition of further intake (increased satiety). The influence of dietary protein on feeding behaviour in C57BL/6J mice was tested using an automated FI monitoring system (BioDAQ), simultaneous to body temperature (Tb). Total FI, inter meal intervals (IMI, satiety) and meal size (MS, satiation) were related to changes in Tb after consuming low (5%, LP), moderate (15%, MP) and high (30%, HP) protein diets. Diets were tested over …

Distinct Basal Forebrain-Originated Neural Circuits Promote Homoeostatic Feeding And Suppress Hedonic Feeding In Male Mice, Hailan Liu, Jonathan C Bean, Yongxiang Li, Meng Yu, Olivia Z Ginnard, Kristine M Conde, Mengjie Wang, Xing Fang, Hesong Liu, Longlong Tu, Na Yin, Junying Han, Yongjie Yang, Qingchun Tong, Benjamin R Arenkiel, Chunmei Wang, Yang He, Yong Xu

Faculty, Staff and Students Publications

Feeding behaviour is influenced by two primary factors: homoeostatic needs driven by hunger and hedonic desires for pleasure even in the absence of hunger. While efficient homoeostatic feeding is vital for survival, excessive hedonic feeding can lead to adverse consequences such as obesity and metabolic dysregulations. However, the neurobiological mechanisms that orchestrate homoeostatic versus hedonic food consumption remain largely unknown. Here we show that GABAergic proenkephalin (Penk) neurons in the diagonal band of Broca (DBB) of male mice respond to food presentation. We further demonstrate that a subset of DBBPenk neurons that project to the paraventricular nucleus of the hypothalamus …

Lifr Regulates Cholesterol-Driven Bidirectional Hepatocyte-Neutrophil Cross-Talk To Promote Liver Regeneration, Yalan Deng, Zilong Zhao, Marisela Sheldon, Yang Zhao, Hongqi Teng, Consuelo Martinez, Jie Zhang, Chunru Lin, Yutong Sun, Fan Yao, Michael A Curran, Hao Zhu, Li Ma

Faculty, Staff and Student Publications

Liver regeneration is under metabolic and immune regulation. Despite increasing recognition of the involvement of neutrophils in regeneration, it is unclear how the liver signals to the bone marrow to release neutrophils after injury and how reparative neutrophils signal to hepatocytes to reenter the cell cycle. Here we report that loss of the liver tumour suppressor Lifr in mouse hepatocytes impairs, whereas overexpression of leukaemia inhibitory factor receptor (LIFR) promotes liver repair and regeneration after partial hepatectomy or toxic injury. In response to physical or chemical damage to the liver, LIFR from hepatocytes promotes the secretion of cholesterol and CXCL1 …

Optimal Humanized Scg3-Neutralizing Antibodies For Anti-Angiogenic Therapy Of Diabetic Retinopathy, Chengchi Huang, Prabuddha Waduge, Avinash Kaur, Hong Tian, Christina Y Weng, John Timothy Stout, Iok-Hou Pang, Keith A Webster, Wei Li

Faculty, Staff and Students Publications

Secretogranin III (Scg3) is a diabetic retinopathy (DR)-restricted angiogenic factor identified in preclinical studies as a target for DR therapy. Previously, our group generated and characterized ML49.3, an anti-Scg3 monoclonal antibody (mAb) which we then converted into an EBP2 humanized antibody Fab fragment (hFab) with potential for clinical application. We also generated anti-Scg3 mT4 mAb and related EBP3 hFab. In this study, to identify the preferred hFab for DR therapy, we compared all four antibodies for binding, neutralizing and therapeutic activities in vitro and in vivo. Octet binding kinetics analyses revealed that ML49.3 mAb, EBP2 hFab, mT4 mAb and EBP3 …

Transcriptional Coactivation Of Nrf2 Signaling In Cardiac Fibroblasts Promotes Resistance To Oxidative Stress, Lisa K Mcclendon, Rainer B Lanz, Anil Panigrahi, Kristan Gomez, Michael J Bolt, Min Liu, Fabio Stossi, Michael A Mancini, Clifford C Dacso, David M Lonard, Bert W O'Malley

Faculty, Staff and Students Publications

We recently discovered that steroid receptor coactivators (SRCs) SRCs-1, 2 and 3, are abundantly expressed in cardiac fibroblasts (CFs) and their activation with the SRC small molecule stimulator MCB-613 improves cardiac function and dramatically lowers pro-fibrotic signaling in CFs post-myocardial infarction. These findings suggest that CF-derived SRC activation could be beneficial in the mitigation of chronic heart failure after ischemic insult. However, the cardioprotective mechanisms by which CFs contribute to cardiac pathological remodeling are unclear. Here we present studies designed to identify the molecular and cellular circuitry that governs the anti-fibrotic effects of an MCB-613 derivative, MCB-613-10-1, in CFs. We …

Lipid Droplet-Associated Hydrolase Mobilizes Stores Of Liver X Receptor Sterol Ligands And Protects Against Atherosclerosis, Young-Hwa Goo, Janeesh Plakkal Ayyappan, Francis D Cheeran, Sushant Bangru, Pradip K Saha, Paula Baar, Sabine Schulz, Todd A Lydic, Bernhard Spengler, Andreas H Wagner, Auinash Kalsotra, Vijay K Yechoor, Antoni Paul

Faculty, Staff and Students Publications

Foam cells in atheroma are engorged with lipid droplets (LDs) that contain esters of regulatory lipids whose metabolism remains poorly understood. LD-associated hydrolase (LDAH) has a lipase structure and high affinity for LDs of foam cells. Using knockout and transgenic mice of both sexes, here we show that LDAH inhibits atherosclerosis development and promotes stable lesion architectures. Broad and targeted lipidomic analyzes of primary macrophages and comparative lipid profiling of atheroma identified a broad impact of LDAH on esterified sterols, including natural liver X receptor (LXR) sterol ligands. Transcriptomic analyzes coupled with rescue experiments show that LDAH modulates the expression …

Deletion Of Mipep In Adipocytes Protects Against Obesity And Insulin Resistance By Boosting Muscle Metabolism, Alexis Diaz-Vegas, Kristen C Cooke, Harry B Cutler, Belinda Yau, Stewart W C Masson, Dylan Harney, Oliver K Fuller, Meg Potter, Søren Madsen, Niamh R Craw, Yiju Zhang, Cesar L Moreno, Melkam A Kebede, G Gregory Neely, Jacqueline Stöckli, James G Burchfield, David E James

Faculty, Staff and Students Publications

Mitochondria facilitate thousands of biochemical reactions, covering a broad spectrum of anabolic and catabolic processes. Here we demonstrate that the adipocyte mitochondrial proteome is markedly altered across multiple models of insulin resistance and reveal a consistent decrease in the level of the mitochondrial processing peptidase miPEP.

OBJECTIVE: To determine the role of miPEP in insulin resistance.

METHODS: To experimentally test this observation, we generated adipocyte-specific miPEP knockout mice to interrogate its role in the aetiology of insulin resistance.

RESULTS: We observed a strong phenotype characterised by enhanced insulin sensitivity and reduced adiposity, despite normal food intake and physical activity. Strikingly, …

Dose-Dependent Effects Of Dnmt3a In An Inducible Murine Model Of Krasg12d-Driven Leukemia, Jason H Rogers, Allison Rosen, Jaime M Reyes, Shamika Ketkar, Shannon E Conneely, Rohit Gupta, Luibin Yang, Matthew B Miller, Geraldo Medrano, Rogelio Aguilar, Nneka Uchenda, Margaret A Goodell, Rachel E Rau

Children’s Nutrition Research Center Staff Publications

DNMT3A mutations are frequently found in clonal hematopoiesis and a variety of hematologic malignancies including acute myeloid leukemia (AML). An assortment of mouse models have been engineered to explore the tumorigenic potential and malignant lineage bias due to loss of function of DNMT3A in consort with commonly co-mutated genes in myeloid malignancies such as Flt3, Nras, Kras, and c-Kit. We employed several tamoxifen-inducible Cre-ER^T2 murine model systems to study the effects of constitutively active Kras^G12D-driven myeloid leukemia (Kras) development together with heterozygous (3aHet) or homozygous Dnmt3a deletion (3aKO). Due to the rapid generation of …

Nfatc1 Is Required For Vitamin D- And Phosphate-Mediated Regulation Of Osteocyte Lacuno-Canalicular Remodeling, Supriya Jagga, Ashleigh Hughes, Niusha Manoochehri Arash, Melissa Sorsby, Daniel J Brooks, Paola Divieti Pajevic, Eva S Liu

Staff and Researcher Publications

Osteocytes are embedded in lacunae and connected by canaliculi (lacuno-canalicular network, LCN). Bones from mice with X-linked hypophosphatemia (Hyp), which have impaired production of 1,25 dihydroxyvitamin D (1,25D) and hypophosphatemia, have abnormal LCN structure that is improved by treatment with 1,25D or an anti-FGF23 targeting antibody, supporting roles for 1,25D and phosphate in regulating LCN remodeling. Bones from mice lacking the vitamin D receptor (VDR) in osteocytes (Vdrf/f;Dmp1Cre+) and mice lacking the sodium phosphate transporter 2a (Npt2aKO), which have low serum phosphate with high serum 1,25D, have impaired LCN organization, demonstrating that osteocyte-specific actions of 1,25D and hypophosphatemia regulate LCN …