Open Access. Powered by Scholars. Published by Universities.®

Biochemistry, Biophysics, and Structural Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 15 of 15

Full-Text Articles in Biochemistry, Biophysics, and Structural Biology

High-Fat Diet In A Mouse Insulin-Resistant Model Induces Widespread Rewiring Of The Phosphotyrosine Signaling Network, Antje Dittmann, Norman J. Kennedy, Nina L. Soltero, Nader Morshed, Miyeko D. Mana, Omer H. Yilmaz, Roger J. Davis, Forest M. White Aug 2019

High-Fat Diet In A Mouse Insulin-Resistant Model Induces Widespread Rewiring Of The Phosphotyrosine Signaling Network, Antje Dittmann, Norman J. Kennedy, Nina L. Soltero, Nader Morshed, Miyeko D. Mana, Omer H. Yilmaz, Roger J. Davis, Forest M. White

Open Access Articles

Obesity-associated type 2 diabetes and accompanying diseases have developed into a leading human health risk across industrialized and developing countries. The complex molecular underpinnings of how lipid overload and lipid metabolites lead to the deregulation of metabolic processes are incompletely understood. We assessed hepatic post-translational alterations in response to treatment of cells with saturated and unsaturated free fatty acids and the consumption of a high-fat diet by mice. These data revealed widespread tyrosine phosphorylation changes affecting a large number of enzymes involved in metabolic processes as well as canonical receptor-mediated signal transduction networks. Targeting two of the most prominently affected ...


Impact Of Obesity On Ovotoxicity Induced By 7,12-Dimethylbenz[A]Anthracene In Mice, Jackson Nteeba, Shanthi Ganesan, Aileen F. Keating Jul 2019

Impact Of Obesity On Ovotoxicity Induced By 7,12-Dimethylbenz[A]Anthracene In Mice, Jackson Nteeba, Shanthi Ganesan, Aileen F. Keating

Aileen Keating

Insulin, elevated during obesity, regulates xenobiotic biotransformation enzymes, potentially through phosphatidylinositol 3-kinase (PI3K) signaling, in extraovarian tissues. PI3K regulates oocyte viability, follicular activation, and ovarian chemical biotransformation. 7,12-Dimethylbenz[a]anthracene (DMBA), a carcinogen and ovotoxicant, destroys all stages of follicles, leading to premature ovarian failure. Obesity has been reported to promote DMBA-induced tumors, but it remains unknown whether obesity affects ovarian xenobiotic metabolism. Therefore, we investigated ovarian expression of xenobiotic metabolism genes—microsomal epoxide hydrolase (Ephx1), glutathione S-transferase (GST) class Pi (Gstp1) and class mu 1 (Gstm1), and PI3K-signaling members (protein kinase B [AKT] alpha [Akt1], beta [Akt2], and ...


Hepatic Dysfunction Caused By Consumption Of A High-Fat Diet, Anthony R. Soltis, Norman J. Kennedy, Xiaofeng Xin, Feng Zhou, Scott B. Ficarro, Yoon Sing Yap, Bryan J. Matthews, Douglas A. Lauffenburger, Forest M. White, Jarrod A. Marto, Roger J. Davis, Ernest Fraenkel Dec 2017

Hepatic Dysfunction Caused By Consumption Of A High-Fat Diet, Anthony R. Soltis, Norman J. Kennedy, Xiaofeng Xin, Feng Zhou, Scott B. Ficarro, Yoon Sing Yap, Bryan J. Matthews, Douglas A. Lauffenburger, Forest M. White, Jarrod A. Marto, Roger J. Davis, Ernest Fraenkel

University of Massachusetts Medical School Faculty Publications

Obesity is a major human health crisis that promotes insulin resistance and, ultimately, type 2 diabetes. The molecular mechanisms that mediate this response occur across many highly complex biological regulatory levels that are incompletely understood. Here, we present a comprehensive molecular systems biology study of hepatic responses to high-fat feeding in mice. We interrogated diet-induced epigenomic, transcriptomic, proteomic, and metabolomic alterations using high-throughput omic methods and used a network modeling approach to integrate these diverse molecular signals. Our model indicated that disruption of hepatic architecture and enhanced hepatocyte apoptosis are among the numerous biological processes that contribute to early liver ...


Prospective Relation Of Circulating Adipokines To Incident Metabolic Syndrome: The Framingham Heart Study, Justin P. Zachariah, Rene Quiroz, Kerrie P. Nelson, Zhaoyang Teng, John F. Keaney Jr., Lisa M. Sullivan, Ramachandran S. Vasan Jul 2017

Prospective Relation Of Circulating Adipokines To Incident Metabolic Syndrome: The Framingham Heart Study, Justin P. Zachariah, Rene Quiroz, Kerrie P. Nelson, Zhaoyang Teng, John F. Keaney Jr., Lisa M. Sullivan, Ramachandran S. Vasan

UMass Metabolic Network Publications

BACKGROUND: Adipokines are elaborated by adipose tissue and are associated with glycemic, lipid, and vascular traits. We hypothesized that in a cross-sectional analysis circulating adipokines are altered among subsets of obesity stratified by presence versus absence of metabolic syndrome (MetS) and prospectively predict the incidence of MetS.

METHODS AND RESULTS: Participants in the community-based Framingham Third Generation Cohort who attended examination cycle 1 were included in the study (2002-2005; N=3777, mean age, 40 years; 59% women). Circulating adiponectin, leptin, leptin receptor, fetuin-A, fatty acid-binding protein 4, and retinol binding protein 4 were assayed and related to incident MetS in ...


Map4k4 Impairs Energy Metabolism In Endothelial Cells And Promotes Insulin Resistance In Obesity, Rachel J. Roth Flach, Marina T. Distefano, Laura V. Danai, Ozlem Senol-Cosar, Joseph C. Yawe, Mark Kelly, Lorena Garcia Menendez, Michael P. Czech Jun 2017

Map4k4 Impairs Energy Metabolism In Endothelial Cells And Promotes Insulin Resistance In Obesity, Rachel J. Roth Flach, Marina T. Distefano, Laura V. Danai, Ozlem Senol-Cosar, Joseph C. Yawe, Mark Kelly, Lorena Garcia Menendez, Michael P. Czech

UMass Metabolic Network Publications

The blood vasculature responds to insulin, influencing hemodynamic changes in the periphery, which promotes tissue nutrient and oxygen delivery and thus metabolic function. The lymphatic vasculature regulates fluid and lipid homeostasis, and impaired lymphatic function can contribute to atherosclerosis and obesity. Recent studies have suggested a role for endothelial cell (EC) Mitogen activated protein kinase kinase kinase kinase 4 (Map4k4) in developmental angiogenesis and lymphangiogenesis as well as atherosclerosis. Here, we show that inducible EC Map4k4 deletion in adult mice ameliorates metabolic dysfunction in obesity despite the development of chylous ascites and a concomitant striking increase in adipose tissue lymphocyte ...


Gestational Diabetes Mellitus And The Predisposing Factors, Syeda Sadia Fatima, Rehana Rehman, Faiza Alam, Sarosh Madhani, Bushra Chaudhry, Taseer Ahmed Khan Feb 2017

Gestational Diabetes Mellitus And The Predisposing Factors, Syeda Sadia Fatima, Rehana Rehman, Faiza Alam, Sarosh Madhani, Bushra Chaudhry, Taseer Ahmed Khan

Department of Biological & Biomedical Sciences

Objective: To evaluate the occurrence of gestational diabetes mellitus and its association with demographic and anthropometric variables in pregnant women.
Methods: This cross-sectional study was conducted at the Aga Khan University Hospital, Abbasi Shaheed Hospital and Memon Hospital in Karachi, from February 2014 to December 2015, and comprised pregnant women who were screened by 75-g 2-hour oral glucose tolerance test, (24-28 weeks of gestation) and classified as per the criteria of the International Association of Diabetes and Pregnancy Study Group. Weight, body mass index and serum glycated haemoglobin levels were measured. Women with pre-gestational diabetes were excluded. SPSS 21 was ...


Amplification Of Adipogenic Commitment By Vstm2a, Blandine Secco, Peter L. Lee, David A. Guertin, Mathieu Laplante Jan 2017

Amplification Of Adipogenic Commitment By Vstm2a, Blandine Secco, Peter L. Lee, David A. Guertin, Mathieu Laplante

UMass Metabolic Network Publications

Despite progress in our comprehension of the mechanisms regulating adipose tissue development, the nature of the factors that functionally characterize adipose precursors is still elusive. Defining the early steps regulating adipocyte development is needed for the generation of tools to control adipose tissue size and function. Here, we report the discovery of V-set and transmembrane domain containing 2A (VSTM2A) as a protein expressed and secreted by committed preadipocytes. VSTM2A expression is elevated in the early phases of adipogenesis in vitro and adipose tissue development in vivo. We show that VSTM2A-producing cells associate with the vasculature and express the common surface ...


Systemic Insulin Sensitivity Is Regulated By Gps2 Inhibition Of Akt Ubiquitination And Activation In Adipose Tissue, Carly T. Cederquist, Claudia Lentucci, Camila Martinez Calejman, Vanessa Hayashi, Joseph Orofino, David A. Guertin, Susan K. Fried, Mi-Jeong Lee, M. Dafne Cardamone, Valentina Perissi Jan 2017

Systemic Insulin Sensitivity Is Regulated By Gps2 Inhibition Of Akt Ubiquitination And Activation In Adipose Tissue, Carly T. Cederquist, Claudia Lentucci, Camila Martinez Calejman, Vanessa Hayashi, Joseph Orofino, David A. Guertin, Susan K. Fried, Mi-Jeong Lee, M. Dafne Cardamone, Valentina Perissi

Open Access Articles

OBJECTIVE: Insulin signaling plays a unique role in the regulation of energy homeostasis and the impairment of insulin action is associated with altered lipid metabolism, obesity, and Type 2 Diabetes. The main aim of this study was to provide further insight into the regulatory mechanisms governing the insulin signaling pathway by investigating the role of non-proteolytic ubiquitination in insulin-mediated activation of AKT.

METHODS: The molecular mechanism of AKT regulation through ubiquitination is first dissected in vitro in 3T3-L1 preadipocytes and then validated in vivo using mice with adipo-specific deletion of GPS2, an endogenous inhibitor of Ubc13 activity (GPS2-AKO mice).

RESULTS ...


Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown Dec 2016

Extracellular Matrix Remodeling And The Inflammatory Response During Skeletal Muscle Regeneration In Sarcopenic Obese Mice, Lemuel Arthur Brown

Theses and Dissertations

AIM: Sarocpenic obesity is a national concern within the United States because this metabolic syndrome is tied with reduced mobility and quality of life. Both obesity and aging are associated with insulin-resistance, chronic low-grade inflammation and muscle weakness. Skeletal muscle regeneration is a process that involves the coordinated effort of myogenic regulatory factors (MRFs), inflammatory signaling, and extracellular matrix (ECM) remodeling for optimal regeneration. It has been demonstrated that obesity and aging have a reduction in muscle regeneration. It has not been examined if sarcopenic obesity will further reduce muscle mass and the regenerative process. The purpose of this study ...


Adipocyte-Specific Hypoxia-Inducible Gene 2 Promotes Fat Deposition And Diet-Induced Insulin Resistance, Marina Distefano, Rachel J. Roth Flach, Ozlem Senol-Cosar, Laura V. Danai, Joseph V. Virbasius, Sarah M. Nicoloro, Juerg R. Straubhaar, Sezin Dagdeviren, Martin Wabitsch, Olga T. Gupta, Jason K. Kim, Michael P. Czech Sep 2016

Adipocyte-Specific Hypoxia-Inducible Gene 2 Promotes Fat Deposition And Diet-Induced Insulin Resistance, Marina Distefano, Rachel J. Roth Flach, Ozlem Senol-Cosar, Laura V. Danai, Joseph V. Virbasius, Sarah M. Nicoloro, Juerg R. Straubhaar, Sezin Dagdeviren, Martin Wabitsch, Olga T. Gupta, Jason K. Kim, Michael P. Czech

Open Access Articles

OBJECTIVE: Adipose tissue relies on lipid droplet (LD) proteins in its role as a lipid-storing endocrine organ that controls whole body metabolism. Hypoxia-inducible Gene 2 (Hig2) is a recently identified LD-associated protein in hepatocytes that promotes hepatic lipid storage, but its role in the adipocyte had not been investigated. Here we tested the hypothesis that Hig2 localization to LDs in adipocytes promotes adipose tissue lipid deposition and systemic glucose homeostasis.

METHOD: White and brown adipocyte-deficient (Hig2fl/fl x Adiponection cre+) and selective brown/beige adipocyte-deficient (Hig2fl/fl x Ucp1 cre+) mice were generated to investigate the role of Hig2 in ...


A Major Role Of Insulin In Promoting Obesity-Associated Adipose Tissue Inflammation, David J. Pedersen, Adilson L Guilherme, Laura V. Danai, Lauren Heyda, Anouch Matevossian, Jessica L. Cohen, Sarah M. Nicoloro, Juerg R. Straubhaar, Hye Lim Noh, Dae Young Jung, Jason K. Kim, Michael P. Czech May 2015

A Major Role Of Insulin In Promoting Obesity-Associated Adipose Tissue Inflammation, David J. Pedersen, Adilson L Guilherme, Laura V. Danai, Lauren Heyda, Anouch Matevossian, Jessica L. Cohen, Sarah M. Nicoloro, Juerg R. Straubhaar, Hye Lim Noh, Dae Young Jung, Jason K. Kim, Michael P. Czech

Open Access Articles

OBJECTIVE: Adipose tissue (AT) inflammation is associated with systemic insulin resistance and hyperinsulinemia in obese rodents and humans. A longstanding concept is that hyperinsulinemia may promote systemic insulin resistance through downregulation of its receptor on target tissues. Here we tested the novel hypothesis that insulin also impairs systemic insulin sensitivity by specifically enhancing adipose inflammation.

METHODS: Circulating insulin levels were reduced by about 50% in diet-induced and genetically obese mice by treatments with diazoxide or streptozotocin, respectively. We then examined AT crown-like structures, macrophage markers and pro-inflammatory cytokine expression in AT. AT lipogenesis and systemic insulin sensitivity was also monitored ...


Impact Of Obesity On Ovotoxicity Induced By 7,12-Dimethylbenz[A]Anthracene In Mice, Jackson Nteeba, Shanthi Ganesan, Aileen F. Keating Mar 2014

Impact Of Obesity On Ovotoxicity Induced By 7,12-Dimethylbenz[A]Anthracene In Mice, Jackson Nteeba, Shanthi Ganesan, Aileen F. Keating

Animal Science Publications

Insulin, elevated during obesity, regulates xenobiotic biotransformation enzymes, potentially through phosphatidylinositol 3-kinase (PI3K) signaling, in extraovarian tissues. PI3K regulates oocyte viability, follicular activation, and ovarian chemical biotransformation. 7,12-Dimethylbenz[a]anthracene (DMBA), a carcinogen and ovotoxicant, destroys all stages of follicles, leading to premature ovarian failure. Obesity has been reported to promote DMBA-induced tumors, but it remains unknown whether obesity affects ovarian xenobiotic metabolism. Therefore, we investigated ovarian expression of xenobiotic metabolism genes—microsomal epoxide hydrolase (Ephx1), glutathione S-transferase (GST) class Pi (Gstp1) and class mu 1 (Gstm1), and PI3K-signaling members (protein kinase B [AKT] alpha [Akt1], beta [Akt2], and ...


Diet-Induced Obesity Mediated By The Jnk/Dio2 Signal Transduction Pathway, Santiago Vernia, Julie Cavanagh-Kyros, Tamera Barrett, Dae Young Jung, Jason K. Kim, Roger J. Davis Nov 2013

Diet-Induced Obesity Mediated By The Jnk/Dio2 Signal Transduction Pathway, Santiago Vernia, Julie Cavanagh-Kyros, Tamera Barrett, Dae Young Jung, Jason K. Kim, Roger J. Davis

Program in Molecular Medicine Publications and Presentations

The cJun N-terminal kinase (JNK) signaling pathway is a key mediator of metabolic stress responses caused by consuming a high-fat diet, including the development of obesity. To test the role of JNK, we examined diet-induced obesity in mice with targeted ablation of Jnk genes in the anterior pituitary gland. These mice exhibited an increase in the pituitary expression of thyroid-stimulating hormone (TSH), an increase in the blood concentration of thyroid hormone (T4), increased energy expenditure, and markedly reduced obesity compared with control mice. The increased amount of pituitary TSH was caused by reduced expression of type 2 iodothyronine deiodinase (Dio2 ...


Elongation Factor 1a-1 And Hepatocyte Response To Fatty Acid Excess, Alexandra M. Stoianov Apr 2013

Elongation Factor 1a-1 And Hepatocyte Response To Fatty Acid Excess, Alexandra M. Stoianov

Electronic Thesis and Dissertation Repository

Obesity is associated with elevated levels of serum fatty acids, which accumulate in nonadipose tissues including the liver. Elongation factor 1A-1 (EF1A-1) has previously been shown to participate in the cell stress and death response of cardiomyocytes to excess saturated fatty exposure, and in steatotic mouse myocardium. In this thesis, the hypothesis that the hepatocyte response to fatty acid overload involves EF1A-1 was tested. EF1A-1 expression was induced in the livers of obese mice in association with severe hepatic steatosis, and in HepG2 human hepatoma cells in response to excess palmitate. Partial translocation of EF1A-1 from the ER to polymerized ...


Green Tea Extract Protects Against Fibrogenesis Associated With Nonalcoholic Fatty Liver Disease In Diet-Induced Obese Rats, Allyson M. Bower Aug 2012

Green Tea Extract Protects Against Fibrogenesis Associated With Nonalcoholic Fatty Liver Disease In Diet-Induced Obese Rats, Allyson M. Bower

Master's Theses

No abstract provided.