Medicine and Health Sciences Commons^™

Genetic Drivers Of Heterogeneity In Type 2 Diabetes Pathophysiology, Ken Suzuki, Konstantinos Hatzikotoulas, Lorraine Southam, Henry J Taylor, Xianyong Yin, Kim M Lorenz, Ravi Mandla, Alicia Huerta-Chagoya, Giorgio E M Melloni, Stavroula Kanoni, Nigel W Rayner, Ozvan Bocher, Ana Luiza Arruda, Kyuto Sonehara, Shinichi Namba, Simon S K Lee, Michael H Preuss, Lauren E Petty, Philip Schroeder, Brett Vanderwerff, Mart Kals, Fiona Bragg, Kuang Lin, Xiuqing Guo, Weihua Zhang, Jie Yao, Young Jin Kim, Mariaelisa Graff, Fumihiko Takeuchi, Jana Nano, Amel Lamri, Masahiro Nakatochi, Sanghoon Moon, Robert A Scott, James P Cook, Jung-Jin Lee, Ian Pan, Daniel Taliun, Esteban J Parra, Jin-Fang Chai, Lawrence F Bielak, Yasuharu Tabara, Yang Hai, Gudmar Thorleifsson, Niels Grarup, Tamar Sofer, Matthias Wuttke, Chloé Sarnowski, Christian Gieger, Darryl Nousome, Stella Trompet, Soo-Heon Kwak, Jirong Long, Meng Sun, Lin Tong, Wei-Min Chen, Suraj S Nongmaithem, Raymond Noordam, Victor J Y Lim, Claudia H T Tam, Yoonjung Yoonie Joo, Chien-Hsiun Chen, Laura M Raffield, Bram Peter Prins, Aude Nicolas, Lisa R Yanek, Guanjie Chen, Jennifer A Brody, Edmond Kabagambe, Ping An, Anny H Xiang, Hyeok Sun Choi, Brian E Cade, Jingyi Tan, K Alaine Broadaway, Alice Williamson, Zoha Kamali, Jinrui Cui, Manonanthini Thangam, Linda S Adair, Adebowale Adeyemo, Carlos A Aguilar-Salinas, Tarunveer S Ahluwalia, Sonia S Anand, Alain Bertoni, Jette Bork-Jensen, Ivan Brandslund, Thomas A Buchanan, Charles F Burant, Adam S Butterworth, Mickaël Canouil, Juliana C N Chan, Li-Ching Chang, Miao-Li Chee, Ji Chen, Shyh-Huei Chen, Yuan-Tsong Chen, Zhengming Chen, Lee-Ming Chuang, Mary Cushman, John Danesh, Swapan K Das, H Janaka De Silva, George Dedoussis, Latchezar Dimitrov, Ayo P Doumatey, Shufa Du, Qing Duan, Kai-Uwe Eckardt, Leslie S Emery, Daniel S Evans, Michele K Evans, Krista Fischer, James S Floyd, Ian Ford, Oscar H Franco, Timothy M Frayling, Barry I Freedman, Pauline Genter, Hertzel C Gerstein, Vilmantas Giedraitis, Clicerio González-Villalpando, Maria Elena González-Villalpando, Penny Gordon-Larsen, Myron Gross, Lindsay A Guare, Sophie Hackinger, Liisa Hakaste, Sohee Han, Andrew T Hattersley, Christian Herder, Momoko Horikoshi, Annie-Green Howard, Willa Hsueh, Mengna Huang, Wei Huang, Yi-Jen Hung, Mi Yeong Hwang, Chii-Min Hwu, Sahoko Ichihara, Mohammad Arfan Ikram, Martin Ingelsson, Md Tariqul Islam, Masato Isono, Hye-Mi Jang, Farzana Jasmine, Guozhi Jiang, Jost B Jonas, Torben Jørgensen, Frederick K Kamanu, Fouad R Kandeel, Anuradhani Kasturiratne, Tomohiro Katsuya, Varinderpal Kaur, Takahisa Kawaguchi, Jacob M Keaton, Abel N Kho, Chiea-Chuen Khor, Muhammad G Kibriya, Duk-Hwan Kim, Florian Kronenberg, Johanna Kuusisto, Kristi Läll, Leslie A Lange, Kyung Min Lee, Myung-Shik Lee, Nanette R Lee, Aaron Leong, Liming Li, Yun Li, Ruifang Li-Gao, Symen Ligthart, Cecilia M Lindgren, Allan Linneberg, Ching-Ti Liu, Jianjun Liu, Adam E Locke, Tin Louie, Jian'an Luan, Andrea O Luk, Xi Luo, Jun Lv, Julie A Lynch, Valeriya Lyssenko, Shiro Maeda, Vasiliki Mamakou, Sohail Rafik Mansuri, Koichi Matsuda, Thomas Meitinger, Olle Melander, Andres Metspalu, Huan Mo, Andrew D Morris, Filipe A Moura, Jerry L Nadler, Michael A Nalls, Uma Nayak, Ioanna Ntalla, Yukinori Okada, Lorena Orozco, Sanjay R Patel, Snehal Patil, Pei Pei, Mark A Pereira, Annette Peters, Fraser J Pirie, Hannah G Polikowsky, Bianca Porneala, Gauri Prasad, Laura J Rasmussen-Torvik, Alexander P Reiner, Michael Roden, Rebecca Rohde, Katheryn Roll, Charumathi Sabanayagam, Kevin Sandow, Alagu Sankareswaran, Naveed Sattar, Sebastian Schönherr, Mohammad Shahriar, Botong Shen, Jinxiu Shi, Dong Mun Shin, Nobuhiro Shojima, Jennifer A Smith, Wing Yee So, Alena Stančáková, Valgerdur Steinthorsdottir, Adrienne M Stilp, Konstantin Strauch, Kent D Taylor, Barbara Thorand, Unnur Thorsteinsdottir, Brian Tomlinson, Tam C Tran, Fuu-Jen Tsai, Jaakko Tuomilehto, Teresa Tusie-Luna, Miriam S Udler, Adan Valladares-Salgado, Rob M Van Dam, Jan B Van Klinken, Rohit Varma, Niels Wacher-Rodarte, Eleanor Wheeler, Ananda R Wickremasinghe, Ko Willems Van Dijk, Daniel R Witte, Chittaranjan S Yajnik, Ken Yamamoto, Kenichi Yamamoto, Kyungheon Yoon, Canqing Yu, Jian-Min Yuan, Salim Yusuf, Matthew Zawistowski, Liang Zhang, Wei Zheng, Leslie J Raffel, Michiya Igase, Eli Ipp, Susan Redline, Yoon Shin Cho, Lars Lind, Michael A Province, Myriam Fornage, Craig L Hanis, Erik Ingelsson, Alan B Zonderman, Bruce M Psaty, Ya-Xing Wang, Charles N Rotimi, Diane M Becker, Fumihiko Matsuda, Yongmei Liu, Mitsuhiro Yokota, Sharon L R Kardia, Patricia A Peyser, James S Pankow, James C Engert, Amélie Bonnefond, Philippe Froguel, James G Wilson, Wayne H H Sheu, Jer-Yuarn Wu, M Geoffrey Hayes, Ronald C W Ma, Tien-Yin Wong, Dennis O Mook-Kanamori, Tiinamaija Tuomi, Giriraj R Chandak, Francis S Collins, Dwaipayan Bharadwaj, Guillaume Paré, Michèle M Sale, Habibul Ahsan, Ayesha A Motala, Xiao-Ou Shu, Kyong-Soo Park, J Wouter Jukema, Miguel Cruz, Yii-Der Ida Chen, Stephen S Rich, Roberta Mckean-Cowdin, Harald Grallert, Ching-Yu Cheng, Mohsen Ghanbari, E-Shyong Tai, Josee Dupuis, Norihiro Kato, Markku Laakso, Anna Köttgen, Woon-Puay Koh, Donald W Bowden, Colin N A Palmer, Jaspal S Kooner, Charles Kooperberg, Simin Liu, Kari E North, Danish Saleheen, Torben Hansen, Oluf Pedersen, Nicholas J Wareham, Juyoung Lee, Bong-Jo Kim, Iona Y Millwood, Robin G Walters, Kari Stefansson, Emma Ahlqvist, Mark O Goodarzi, Karen L Mohlke, Claudia Langenberg, Christopher A Haiman, Ruth J F Loos, Jose C Florez, Daniel J Rader, Marylyn D Ritchie, Sebastian Zöllner, Reedik Mägi, Nicholas A Marston, Christian T Ruff, David A Van Heel, Sarah Finer, Joshua C Denny, Toshimasa Yamauchi, Takashi Kadowaki, John C Chambers, Maggie C Y Ng, Xueling Sim, Jennifer E Below, Philip S Tsao, Kyong-Mi Chang, Mark I Mccarthy, James B Meigs, Anubha Mahajan, Cassandra N Spracklen, Josep M Mercader, Michael Boehnke, Jerome I Rotter, Marijana Vujkovic, Benjamin F Voight, Andrew P Morris, Eleftheria Zeggini

Journal Articles

Type 2 diabetes (T2D) is a heterogeneous disease that develops through diverse pathophysiological processes1,2 and molecular mechanisms that are often specific to cell type3,4. Here, to characterize the genetic contribution to these processes across ancestry groups, we aggregate genome-wide association study data from 2,535,601 individuals (39.7% not of European ancestry), including 428,452 cases of T2D. We identify 1,289 independent association signals at genome-wide significance (P < 5 × 10-8) that map to 611 loci, of which 145 loci are, to our knowledge, previously unreported. We define eight non-overlapping clusters of T2D signals that are characterized by distinct profiles of cardiometabolic trait associations. These clusters are differentially enriched for cell-type-specific regions of open chromatin, including pancreatic islets, adipocytes, endothelial cells and enteroendocrine cells. We build cluster-specific partitioned polygenic scores5 in a further 279,552 individuals of diverse ancestry, including 30,288 cases of T2D, and test their association with T2D-related vascular outcomes. Cluster-specific partitioned polygenic scores are associated with coronary artery disease, peripheral artery disease and end-stage diabetic nephropathy across ancestry groups, highlighting the importance of obesity-related processes in the development of vascular outcomes. Our findings show the value of integrating multi-ancestry genome-wide association study data with single-cell epigenomics to disentangle the aetiological heterogeneity that drives the development and progression of T2D. This might offer a route to optimize global access to genetically informed diabetes care.

Connexin43 In Mesenchymal Lineage Cells Regulates Body Adiposity And Energy Metabolism In Mice, Seung-Yon Lee, Francesca Fontana, Toshifumi Sugatani, Ignacio Portales Castillo, Giulia Leanza, Ariella Coler-Reilly, Roberto Civitelli

2020-Current year OA Pubs

Connexin43 (Cx43) is the most abundant gap junction protein present in the mesenchymal lineage. In mature adipocytes, Cx43 mediates white adipose tissue (WAT) beiging in response to cold exposure and maintains the mitochondrial integrity of brown adipose tissue (BAT). We found that genetic deletion of Gja1 (Cx43 gene) in cells that give rise to chondro-osteogenic and adipogenic precursors driven by the Dermo1/Twist2 promoter led to lower body adiposity and partial protection against the weight gain and metabolic syndrome induced by a high-fat diet (HFD) in both sexes. These protective effects were related to increased locomotion, fuel utilization, energy expenditure, nonshivering …

Tet3 Plays A Critical Role In White Adipose Development And Diet-Induced Remodeling, Byung Chul Jung, Dongjoo You, Ikjun Lee, Daofeng Li, Rebecca L Schill, Katherine Ma, Anna Pi, Zehan Song, Wei-Chieh Mu, Ting Wang, Ormond A Macdougald, Alexander S Banks, Sona Kang

2020-Current year OA Pubs

Maintaining healthy adipose tissue is crucial for metabolic health, requiring a deeper understanding of adipocyte development and response to high-calorie diets. This study highlights the importance of TET3 during white adipose tissue (WAT) development and expansion. Selective depletion of Tet3 in adipose precursor cells (APCs) reduces adipogenesis, protects against diet-induced adipose expansion, and enhances whole-body metabolism. Transcriptomic analysis of wild-type and Tet3 knockout (KO) APCs unveiled TET3 target genes, including Pparg and several genes linked to the extracellular matrix, pivotal for adipogenesis and remodeling. DNA methylation profiling and functional studies underscore the importance of DNA demethylation in gene regulation. Remarkably, …

The Circadian Nobiletin-Ror Axis Suppresses Adipogenic Differentiation And Iκbα/Nf-Κb Signaling In Adipocytes, Eunju Kim, Kazuaki Mawatari, Seung-Hee Yoo, Zheng Chen

Journal Articles

Obesity is a known risk factor for metabolic diseases and is often associated with chronic inflammation in adipose tissue. We previously identified the polyethoxylated flavonoid Nobiletin (NOB) as a circadian clock modulator that directly binds to and activates the ROR receptors in the core oscillator, markedly improving metabolic fitness in obese mice. Here, we show that NOB enhanced the oscillation of core clock genes in differentiated 3T3-L1 adipocytes, including ROR target genes such as Bmal1, Cry1, Dec1, and Dec2. NOB inhibited lipid accumulation in 3T3-L1 and SVF cells, concomitant with the dysregulated circadian expression of adipogenic …

Determining The Existence And Regulation Of Microlipophagy In Primary Brown And White Adipocytes, Sara C. Arenas De Leon

Biomedical Sciences ETDs

Lipids are one of life’s four main macromolecules and provide essential functions to cells.

The degradation of lipid droplets and mobilization of lipids occurs through lipolysis. Emerging evidence demonstrates evidence of a selective form of autophagy in lipolysis. The process of microlipophagy has only recently been described, and many features of its regulation are still poorly understood. Our recent study showed that inhibiting mammalian target of rapamycin complex 1 (mTORC1) pathway by depletion of Raptor in adipocytes led to an influx of lysosomes and accumulation of lipid droplets within lysosome. Here, we expand on these previous findings. We were able …

Arsenic Metabolism, Diabetes Prevalence, And Insulin Resistance Among Mexican Americans: A Mendelian Randomization Approach, Margaret C Weiss, Yu-Hsuan Shih, Molly Scannell Bryan, Brian P Jackson, David Aguilar, Eric L Brown, Goo Jun, Craig L Hanis, Maria Argos, Robert M Sargis

Journal Articles

BACKGROUND: Differences in arsenic metabolism capacity may influence risk for type 2 diabetes, but the mechanistic drivers are unclear. We evaluated the associations between arsenic metabolism with overall diabetes prevalence and with static and dynamic measures of insulin resistance among Mexican Americans living in Starr County, Texas.

METHODS: We utilized data from cross-sectional studies conducted in Starr County, Texas, from 2010-2014. A Mendelian randomization approach was utilized to evaluate the associations between arsenic metabolism and type 2 diabetes prevalence using the intronic variant in the arsenic methylating gene, rs9527, as the instrumental variable for arsenic metabolism. to further assess mechanisms …

Determining The Existence And Regulation Of Microlipophagy In Primary Brown And White Adipocytes, Sara C. Arenas De Leon

Biomedical Sciences ETDs

Lipids are one of life’s four main macromolecules and provide essential functions to cells, as they serve as building blocks of cellular membranes, mediate cell signaling, and are a critical energy source. Within cells, esterified fatty acids aggregate into lipid droplets in the form of triglycerides, consisting of a neutral lipid core surrounded by a phospholipid monolayer decorated with various proteins.

The degradation of lipid droplets and mobilization of lipids occurs through lipolysis, a process that hydrolyzes a molecule of triglyceride into a glycerol and three fatty acids. Emerging evidence demonstrates the involvement of a selective form of autophagy in …

Anti-Diabetic Effects Of Glp1 Analogs Are Mediated By Thermogenic Interleukin-6 Signaling In Adipocytes, Absalon D Gutierrez, Zhanguo Gao, Vala Hamidi, Liang Zhu, Karla Bermudez Saint Andre, Kayla Riggs, Monika Ruscheinsky, Hongyu Wang, Yongmei Yu, Charles Miller, Hernan Vasquez, Heinrich Taegtmeyer, Mikhail G Kolonin

Journal Articles

Mechanisms underlying anti-diabetic effects of GLP1 analogs remain incompletely understood. We observed that in prediabetic humans exenatide treatment acutely induces interleukin-6 (IL-6) secretion by monocytes and IL-6 in systemic circulation. We hypothesized that GLP1 analogs signal through IL-6 in adipose tissue (AT) and used the mouse model to test if IL-6 receptor (IL-6R) signaling underlies the effects of the GLP1-IL-6 axis. We show that liraglutide transiently increases IL-6 in mouse circulation and IL-6R signaling in AT. Metronomic liraglutide treatment resulted in AT browning and thermogenesis linked with STAT3 activation. IL-6-blocking antibody treatment inhibited STAT3 activation in AT and suppressed liraglutide-induced …

Anti-Diabetic Effects Of Glp1 Analogs Are Mediated By Thermogenic Interleukin-6 Signaling In Adipocytes, Absalon D Gutierrez, Zhanguo Gao, Vala Hamidi, Liang Zhu, Karla Bermudez Saint Andre, Kayla Riggs, Monika Ruscheinsky, Hongyu Wang, Yongmei Yu, Charles Miller, Hernan Vasquez, Heinrich Taegtmeyer, Mikhail G Kolonin

Journal Articles

Mechanisms underlying anti-diabetic effects of GLP1 analogs remain incompletely understood. We observed that in prediabetic humans exenatide treatment acutely induces interleukin-6 (IL-6) secretion by monocytes and IL-6 in systemic circulation. We hypothesized that GLP1 analogs signal through IL-6 in adipose tissue (AT) and used the mouse model to test if IL-6 receptor (IL-6R) signaling underlies the effects of the GLP1-IL-6 axis. We show that liraglutide transiently increases IL-6 in mouse circulation and IL-6R signaling in AT. Metronomic liraglutide treatment resulted in AT browning and thermogenesis linked with STAT3 activation. IL-6-blocking antibody treatment inhibited STAT3 activation in AT and suppressed liraglutide-induced …

Apoptotic Brown Adipocytes Enhance Energy Expenditure Via Extracellular Inosine, Birte Niemann, Saskia Haufs-Brusberg, Laura Puetz, Martin Feickert, Michelle Y Jaeckstein, Anne Hoffmann, Jelena Zurkovic, Markus Heine, Eva-Maria Trautmann, Christa E Müller, Anke Tönjes, Christian Schlein, Azin Jafari, Holger K Eltzschig, Thorsten Gnad, Matthias Blüher, Natalie Krahmer, Peter Kovacs, Joerg Heeren, Alexander Pfeifer

Journal Articles

Brown adipose tissue (BAT) dissipates energy

Adipose Tissue-Specific Ablation Of Ces1d Causes Metabolic Dysregulation In Mice, Gang Li, Xin Li, Li Yang, Shuyue Wang, Yulin Dai, Baharan Fekry, Lucas Veillon, Lin Tan, Rebecca Berdeaux, Kristin Eckel-Mahan, Philip L Lorenzi, Zhongming Zhao, Richard Lehner, Kai Sun

Journal Articles

Carboxylesterase 1d (Ces1d) is a crucial enzyme with a wide range of activities in multiple tissues. It has been reported to localize predominantly in ER. Here, we found that Ces1d levels are significantly increased in obese patients with type 2 diabetes. Intriguingly, a high level of Ces1d translocates onto lipid droplets where it digests the lipids to produce a unique set of fatty acids. We further revealed that adipose tissue-specific Ces1d knock-out (FKO) mice gained more body weight with increased fat mass during a high fat-diet challenge. The FKO mice exhibited impaired glucose and lipid metabolism and developed exacerbated liver …

P300 Or Cbp Is Required For Insulin-Stimulated Glucose Uptake In Skeletal Muscle And Adipocytes, Vitor F. Martins, Gretchen A. Meyer, Et Al.

2020-Current year OA Pubs

While current thinking posits that insulin signaling to glucose transporter 4 (GLUT4) exocytic translocation and glucose uptake in skeletal muscle and adipocytes is controlled by phosphorylation-based signaling, many proteins in this pathway are acetylated on lysine residues. However, the importance of acetylation and lysine acetyltransferases to insulin-stimulated glucose uptake is incompletely defined. Here, we demonstrate that combined loss of the acetyltransferases E1A binding protein p300 (p300) and cAMP response element binding protein binding protein (CBP) in mouse skeletal muscle caused a complete loss of insulin-stimulated glucose uptake. Similarly, brief (i.e., 1 hour) pharmacological inhibition of p300/CBP acetyltransferase activity recapitulated this …

Macrophage And Adipocyte Interaction As A Source Of Inflammation In Kidney Disease, Cristina Martos-Rus, Goni Katz-Greenberg, Zhao Lin, Eurico Serrano, Diana Whitaker Menezes, Marina Domingo-Vidal, Megan Roche, Kavitha Ramaswamy, D. Craig Hooper, Bonita Falkner, Maria P Martinez Cantarin

Kimmel Cancer Center Faculty Papers

In obesity, adipose tissue derived inflammation is associated with unfavorable metabolic consequences. Uremic inflammation is prevalent and contributes to detrimental outcomes. However, the contribution of adipose tissue inflammation in uremia has not been characterized. We studied the contribution of adipose tissue to uremic inflammation in-vitro, in-vivo and in human samples. Exposure to uremic serum resulted in activation of inflammatory pathways including NFκB and HIF1, upregulation of inflammatory cytokines/chemokines and catabolism with lipolysis, and lactate production. Also, co-culture of adipocytes with macrophages primed by uremic serum resulted in higher inflammatory cytokine expression than adipocytes exposed only to uremic serum. Adipose tissue …

Upregulation Of Cpt1a Is Essential For The Tumor-Promoting Effect Of Adipocytes In Colon Cancer, Xiaopeng Xiong, Yang-An Wen, Rachelle Fairchild, Yekaterina Y. Zaytseva, Heidi L. Weiss, B. Mark Evers, Tianyan Gao

Markey Cancer Center Faculty Publications

Colon tumors grow in an adipose tissue-enriched microenvironment. Locally advanced colon cancers often invade into surrounding adipose tissue with a direct contact with adipocytes. We have previously shown that adipocytes promote tumor growth by modulating cellular metabolism. Here we demonstrate that carnitine palmitoyltransferase I (CPT1A), a key enzyme controlling fatty acid oxidation (FAO), was upregulated in colon cancer cells upon exposure to adipocytes or fatty acids. In addition, CPT1A expression was increased in invasive tumor cells within the adipose tissue compared to tumors without direct contact with adipocytes. Silencing CPT1A abolished the protective effect provided by fatty acids against nutrient …

Therapeutic Efficacy Of Antioxidants In Ameliorating Obesity Phenotype And Associated Comorbidities, Steven Tun, Caleb James Spainhower, Cameron Lee Cottrill, Hari Vishal Lakhani, Sneha S. Pillai, Anum Dilip, Hibba Chaudhry, Joseph I. Shapiro, Komal Sodhi

Pharmacology, Physiology and Toxicology

Obesity has been a worldwide epidemic for decades. Despite the abundant increase in knowledge regarding the etiology and pathogenesis of obesity, the prevalence continues to rise with estimates predicting considerably higher numbers by the year 2030. Obesity is characterized by an abnormal lipid accumulation, however, the physiological consequences of obesity are far more concerning. The development of the obesity phenotype constitutes dramatic alterations in adipocytes, along with several other cellular mechanisms which causes substantial increase in systemic oxidative stress mediated by reactive oxygen species (ROS). These alterations promote a chronic state of inflammation in the body caused by the redox …

The Β3-Adrenergic Receptor Agonist Mirabegron Improves Glucose Homeostasis In Obese Humans, Brian S. Finlin, Hasiyet Memetimin, Beibei Zhu, Amy L. Confides, Hemendra J. Vekaria, Riham H. El Khouli, Zachary R. Johnson, Philip M. Westgate, Jianzhong Chen, Andrew J. Morris, Patrick G. Sullivan, Esther E. Dupont-Versteegden, Philip A. Kern

Internal Medicine Faculty Publications

BACKGROUND. Beige adipose tissue is associated with improved glucose homeostasis in mice. Adipose tissue contains β3-adrenergic receptors (β3-ARs), and this study was intended to determine whether the treatment of obese, insulin-resistant humans with the β3-AR agonist mirabegron, which stimulates beige adipose formation in subcutaneous white adipose tissue (SC WAT), would induce other beneficial changes in fat and muscle and improve metabolic homeostasis.

METHODS. Before and after β3-AR agonist treatment, oral glucose tolerance tests and euglycemic clamps were performed, and histochemical analysis and gene expression profiling were performed on fat and muscle biopsies. PET-CT scans quantified brown adipose tissue volume and …

Characterizing The Roles Of Nuclear Proteins Dbc1, G9a, And Glp In Adipocyte Function And Metabolic Health, Ashley Ann Able

LSU Doctoral Dissertations

Obesity is a metabolic disorder characterized by excess energy storage in adipose tissue and it increases the risk for Type 2 diabetes. Impaired or altered adipocyte function during obesity can contribute to metabolic dysfunction. DBC1 (deleted in breast cancer 1) and EHMTs 1 and 2 (euchromatic histone lysine methyltransferases 1 and 2) have been shown to have a role in fat cell development and function. DBC1 is typically localized in the nucleus and can regulate a variety of epigenetic modifiers, transcription factors, and nuclear receptors. EHMTs 1 and 2, also known respectively as GLP and G9a, were initially classified as …

The Role Of Pannexin 1 During Human Adipogenesis In Vitro, Jamie Emily Ching

Electronic Thesis and Dissertation Repository

Obesity is the unhealthy accumulation of adipose tissue and affects 10% of the global population. A study reported the loss of mouse pannexin 1 (Panx1), a large channel forming protein, increased adipogenesis in murine adipose derived stem cells (ASCs). Our study was designed to determine if human pannexin 1 (PANX1) inhibits adipogenesis in vitro using human ASCs and induced-mesenchymal stem cells (iMSCs) derived from induced pluripotent stem cells (iPSCs). Pharmacological inhibition of PANX1 using carbenoxolone halted adipogenesis in both the ASCs and iMSCs. When PANX1 was inhibited by probenecid, adipogenesis was impeded in iMSCs, but not in ASCs. PANX1-ablated iPSCs …

Localization Of Synapses On Adipocytes And Stromal Vascular Fraction Cells In Adipose Tissue Using Electron And Immunofluorescent Microscopy, Emma Garner

Honors College

Obesity, weight gain and the many metabolic disorders that can arise from being overweight are predominant health issues in America and in the State of Maine. The body’s ability to balance energy intake and energy expenditure is what determines whether a person gains or loses body fat. Although there are many different factors that influence energy storage and expenditure, neural innervation of white and brown fat (or adipose) tissues is an important aspect of energy balance that is not well understood. The Townsend Lab focuses on brain-adipose communication and the role of adipose peripheral nerves in maintaining proper body weight …

Adipose-Derived Autotaxin Regulates Inflammation And Steatosis Associated With Diet-Induced Obesity, J. Anthony Brandon, Maria Kraemer, Julia Vandra, Suchismita Halder, Margo F. Ubele, Andrew J. Morris, Susan S. Smyth

Gill Heart & Vascular Institute Faculty Publications

Autotaxin (ATX) is a secreted enzyme that generates the bioactive lipid lysophosphatidic acid (LPA). We generated mice with global inducible post-natal inactivation or adipose-specific loss of the Enpp2 gene encoding ATX. The animals are phenotypically unremarkable and exhibit differences in adipocyte size and adipose tissue expression of inflammatory genes after high fat feeding without gross differences in fat distribution or body mass. Surprisingly, both models of Enpp2- deficiency exhibited marked protection from high fat diet-induced hepatic steatosis. This phenotype was not associated with differences in dietary fat absorption but may be accounted for by differences in hepatic expression of …

Lipid Phosphate Phosphatase 3 Regulates Adipocyte Sphingolipid Synthesis, But Not Developmental Adipogenesis Or Diet-Induced Obesity In Mice, Lorenzo Frederico, Liping Yang, Jason Brandon, Manikandan Panchatcharam, Hongmei Ren, Paul Mueller, Manjula Sunkara, Diana Escalante-Alcalde, Andrew J. Morris, Susan S. Smyth

Gill Heart & Vascular Institute Faculty Publications

Dephosphorylation of phosphatidic acid (PA) is the penultimate step in triglyceride synthesis. Adipocytes express soluble intracellular PA-specific phosphatases (Lipins) and broader specificity membrane-associated lipid phosphate phosphatases (LPPs) that can also dephosphorylate PA. Inactivation of lipin1 causes lipodystrophy in mice due to defective developmental adipogenesis. Triglyceride synthesis is diminished but not ablated by inactivation of lipin1 in differentiated adipocytes implicating other PA phosphatases in this process. To investigate the possible role of LPPs in adipocyte lipid metabolism and signaling we made mice with adipocyte-targeted inactivation of LPP3 encoded by the Plpp3(Ppap2b) gene. Adipocyte LPP3 deficiency resulted in blunted …

Epoxyeicosatrienoic Acids Regulate Adipocyte Differentiation Of Mouse 3t3 Cells, Via Pgc-1Α Activation, Which Is Required For Ho-1 Expression And Increased Mitochondrial Function, Maayan Waldman, Lars Bellner, Luca Vanella, Joseph Schragenheim, Komal Sodhi, Shailendra P. Singh, Daohong Lin, Anand Lakhkar, Jiangwei Li, Edith Hochhauser, Michael Arad, Zbigniew Darzynkiewicz, Attallah Kappas, Nader G. Abraham

Nader G. Abraham

Epoxyeicosatrienoic acid (EET) contributes to browning of white adipose stem cells to ameliorate obesity/diabetes and insulin resistance. In the current study, we show that EET altered preadipocyte function, enhanced peroxisome proliferation-activated receptor γ coactivator α (PGC-1α) expression, and increased mitochondrial function in the 3T3-L1 preadipocyte subjected to adipogenesis. Cells treated with EET resulted in an increase, P < 0.05, in PGC-1α and a decrease in mitochondria-derived ROS (MitoSox), P < 0.05. The EET increase in heme oxygenase-1 (HO-1) levels is dependent on activation of PGC-1α as cells deficient in PGC-1α (PGC-1α knockout adipocyte cell) have an impaired ability to express HO-1, P …

Epoxyeicosatrienoic Acids Regulate Adipocyte Differentiation Of Mouse 3t3 Cells, Via Pgc-1Α Activation, Which Is Required For Ho-1 Expression And Increased Mitochondrial Function, Maayan Waldman, Lars Bellner, Luca Vanella, Joseph Schragenheim, Komal Sodhi, Shailendra P. Singh, Daohong Lin, Anand Lakhkar, Jiangwei Li, Edith Hochhauser, Michael Arad, Zbigniew Darzynkiewicz, Attallah Kappas, Nader G. Abraham

Komal Sodhi

Epoxyeicosatrienoic acid (EET) contributes to browning of white adipose stem cells to ameliorate obesity/diabetes and insulin resistance. In the current study, we show that EET altered preadipocyte function, enhanced peroxisome proliferation-activated receptor γ coactivator α (PGC-1α) expression, and increased mitochondrial function in the 3T3-L1 preadipocyte subjected to adipogenesis. Cells treated with EET resulted in an increase, P < 0.05, in PGC-1α and a decrease in mitochondria-derived ROS (MitoSox), P < 0.05. The EET increase in heme oxygenase-1 (HO-1) levels is dependent on activation of PGC-1α as cells deficient in PGC-1α (PGC-1α knockout adipocyte cell) have an impaired ability to express HO-1, P < 0.02. Additionally, adipocytes treated with EET exhibited an increase in mitochondrial superoxide dismutase (SOD) in a PGC-1α-dependent manner, P < 0.05. The increase in PGC-1α was associated with an increase in β-catenin, P < 0.05, adiponectin expression, P < 0.05, and lipid accumulation, P < 0.02. EET decreased heme levels and mitochondria-derived ROS (MitoSox), P < 0.05, compared to adipocytes that were untreated. EET also decreased mesoderm-specific transcript (MEST) mRNA and protein levels (P < 0.05). Adipocyte secretion of EET act in an autocrine/paracrine manner to increase PGC-1α is required for activation of HO-1 expression. This is the first study to dissect the mechanism by which the antiadipogenic and anti-inflammatory lipid, EET, induces the PGC-1α signaling cascade and reprograms the adipocyte phenotype by regulating mitochondrial function and HO-1 expression, leading to an increase in healthy, that is, small, adipocytes and a decrease in adipocyte enlargement and terminal differentiation. This is manifested by an increase in mitochondrial function and an increase in the canonical Wnt signaling cascade during adipocyte proliferation and terminal differentiation.

Using Neonatal Skin To Study The Developmental Programming Of Aging, Leryn J. Reynolds, Brett J. Dickens, Benjamin B. Green, Carmen J. Marsit, Kevin J. Pearson

Pharmacology and Nutritional Sciences Faculty Publications

Numerous studies have examined how both negative and positive maternal exposures (environmental contaminants, nutrition, exercise, etc.) impact offspring risk for age-associated diseases such as obesity, type 2 diabetes, hypertension, and others. The purpose of this study was to introduce the foreskin as a novel model to examine developmental programming in human neonates, particularly in regard to adipogenesis and insulin receptor signaling, major contributors to age-associated diseases such as obesity and diabetes. Neonatal foreskin was collected following circumcision and primary dermal fibroblasts were isolated to perform adipocyte differentiation and insulin stimulation experiments. Human neonatal foreskin primary fibroblasts take up lipid when …

Uric Acid-Induced Adipocyte Dysfunction Is Attenuated By Ho-1 Upregulation: Potential Role Of Antioxidant Therapy To Target Obesity, Komal Sodhi, Jordan Hilgefort, Sarah Stevens, Morghan Getty, Nader G. Abraham, Zeid Khitan

Nader G. Abraham

Increased uric acid levels have been implicated in the pathogenesis of metabolic syndrome. To examine the mechanisms by which this occurs, we hypothesized that an increase in heme oxygenase 1, a potent antioxidant gene, will decrease uric acid levels and adipocyte dysfunction via suppression of ROS and xanthine oxidase (XO) levels. We examined the effect of uric acid on adipogenesis in human mesenchymal stem cells (MSCs) in the presence and absence of cobalt protoporphyrin (CoPP), an HO-1 inducer, and tin mesoporphyrin (SnMP), an HO activity inhibitor. Uric acid increased adipogenesis by increasing NADPH oxidase expression and elevation in the adipogenesis …

Adipocytes Activate Mitochondrial Fatty Acid Oxidation And Autophagy To Promote Tumor Growth In Colon Cancer, Yang-An Wen, Xiaopeng Xing, Jennifer W. Harris, Yekaterina Y. Zaytseva, Mihail I. Mitov, Dana L. Napier, Heidi L. Weiss, B. Mark Evers, Tianyan Gao

Markey Cancer Center Faculty Publications

Obesity has been associated with increased incidence and mortality of a wide variety of human cancers including colorectal cancer. However, the molecular mechanism by which adipocytes regulate the metabolism of colon cancer cells remains elusive. In this study, we showed that adipocytes isolated from adipose tissues of colon cancer patients have an important role in modulating cellular metabolism to support tumor growth and survival. Abundant adipocytes were found in close association with invasive tumor cells in colon cancer patients. Co-culture of adipocytes with colon cancer cells led to a transfer of free fatty acids that released from the adipocytes to …

Epoxyeicosatrienoic Acids Regulate Adipocyte Differentiation Of Mouse 3t3 Cells, Via Pgc-1Α Activation, Which Is Required For Ho-1 Expression And Increased Mitochondrial Function, Maayan Waldman, Lars Bellner, Luca Vanella, Joseph Schragenheim, Komal Sodhi, Shailendra P. Singh, Daohong Lin, Anand Lakhkar, Jiangwei Li, Edith Hochhauser, Michael Arad, Zbigniew Darzynkiewicz, Attallah Kappas, Nader G. Abraham

Biochemistry and Microbiology

Epoxyeicosatrienoic acid (EET) contributes to browning of white adipose stem cells to ameliorate obesity/diabetes and insulin resistance. In the current study, we show that EET altered preadipocyte function, enhanced peroxisome proliferation-activated receptor γ coactivator α (PGC-1α) expression, and increased mitochondrial function in the 3T3-L1 preadipocyte subjected to adipogenesis. Cells treated with EET resulted in an increase, P < 0.05, in PGC-1α and a decrease in mitochondria-derived ROS (MitoSox), P < 0.05. The EET increase in heme oxygenase-1 (HO-1) levels is dependent on activation of PGC-1α as cells deficient in PGC-1α (PGC-1α knockout adipocyte cell) have an impaired ability to express HO-1, P < 0.02. Additionally, adipocytes treated with EET exhibited an increase in mitochondrial superoxide dismutase (SOD) in a PGC-1α-dependent manner, P < 0.05. The increase in PGC-1α was associated with an increase in β-catenin, P < 0.05, adiponectin expression, P < 0.05, and lipid accumulation, P < 0.02. EET decreased heme levels and mitochondria-derived ROS (MitoSox), P < 0.05, compared to adipocytes that were untreated. EET also decreased mesoderm-specific transcript (MEST) mRNA and protein levels (P < 0.05). Adipocyte secretion of EET act in an autocrine/paracrine manner to increase PGC-1α is required for activation of HO-1 expression. This is the first study to dissect the mechanism by which the antiadipogenic and anti-inflammatory lipid, EET, induces the PGC-1α signaling cascade and reprograms the adipocyte phenotype by regulating mitochondrial function and HO-1 expression, leading to an increase in healthy, that is, small, adipocytes and a decrease in adipocyte enlargement and terminal differentiation. This is manifested by an increase in mitochondrial function and an increase in the canonical Wnt signaling cascade during adipocyte proliferation and terminal differentiation.

Serum Amyloid A Impairs The Antiinflammatory Properties Of Hdl, Chang Yeop Han, Chongren Tang, Myriam E. Guevara, Hao Wei, Tomasz Wietecha, Baohai Shao, Savitha Subramanian, Mohamed Omer, Shari Wang, Kevin D. O'Brien, Santica M. Marcovina, Thomas N. Wight, Tomas Vaisar, Maria C. De Beer, Frederick C. De Beer, William R. Osborne, Keith B. Elkon, Alan Chait

Physiology Faculty Publications

HDL from healthy humans and lean mice inhibits palmitate-induced adipocyte inflammation; however, the effect of the inflammatory state on the functional properties of HDL on adipocytes is unknown. Here, we found that HDL from mice injected with AgNO₃ fails to inhibit palmitate-induced inflammation and reduces cholesterol efflux from 3T3-L1 adipocytes. Moreover, HDL isolated from obese mice with moderate inflammation and humans with systemic lupus erythematosus had similar effects. Since serum amyloid A (SAA) concentrations in HDL increase with inflammation, we investigated whether elevated SAA is a causal factor in HDL dysfunction. HDL from AgNO₃-injected mice lacking Saa1.1 …

Uric Acid-Induced Adipocyte Dysfunction Is Attenuated By Ho-1 Upregulation: Potential Role Of Antioxidant Therapy To Target Obesity, Komal Sodhi, Jordan Hilgefort, Sarah Stevens, Morghan Getty, Nader G. Abraham, Zeid Khitan

NYMC Faculty Publications

Increased uric acid levels have been implicated in the pathogenesis of metabolic syndrome. To examine the mechanisms by which this occurs, we hypothesized that an increase in heme oxygenase 1, a potent antioxidant gene, will decrease uric acid levels and adipocyte dysfunction via suppression of ROS and xanthine oxidase (XO) levels. We examined the effect of uric acid on adipogenesis in human mesenchymal stem cells (MSCs) in the presence and absence of cobalt protoporphyrin (CoPP), an HO-1 inducer, and tin mesoporphyrin (SnMP), an HO activity inhibitor. Uric acid increased adipogenesis by increasing NADPH oxidase expression and elevation in the adipogenesis …

Simulation Of Cryolipolysis As A Novel Method For Noninvasive Fat Layer Reduction, Abbas Majdabadi, Mohammad Abazari

Turkish Journal of Medical Sciences

Background/aim: Regarding previous problems in conventional liposuction methods, the need for development of new fat removal operations was appreciated. In this study we are going to simulate one of the novel methods, cryolipolysis, aimed to tackle those drawbacks. Materials and methods: We think that simulation of clinical procedures contributes considerably in efficacious performance of the operations. To do this we have attempted to simulate temperature distribution in a sample fat of the human body. Using Abaqus software we have presented the graphical display of temperature-time variations within the medium. Results: Findings of our simulation indicate that tissue temperature decreases after …