Adiponectin is an adipokine that we first identified in the mid-90's that has gained significant attention due to its insulin sensitizing and anti-inflammatory properties. Many papers have belabored the function of adiponectin in the widest spectrum of clinical and preclinical settings, yet there is no unifying mechanism of action available. Here, we would like to build upon our current data and develop further the mechanistic aspects of adiponectin action. We would like to approach this with the following questions: SA 1) What is the mechanism for the potent anti-apoptotic properties exerted by adiponectin on a number of cell types? We have generated a series of mouse models that allow us to provide an inducible pro-apoptotic insult to specific cell types. These """"""""ATTAC"""""""" mice (""""""""Apoptosis Through Triggered Activation of Caspase-8"""""""") are available for pancreatic ? cells, cardiac myocytes, podocytes and several other critical cell types. We have preliminary genetic data highlighting the potent adiponectin-dose dependent effects on survival of cardiac myocytes in this model. We will extend these studies to ? cells and podocytes. The basis for these observations is a reduction of local ceramides and/or an increase in the local sphingosine-1-P levels due to activation of the adiponectin receptors by adiponectin. We will extend our preliminary data and believe that the ceramide-lowering effects of adiponectin mediated by the adiponectin receptors AdipoR1 and AdipoR2 offers the first unifying mechanism of action by which adiponectin achieves its remarkable effects systemically on a wide variety of cells. SA 2) Determine whether there is an """"""""intracrine"""""""" mechanism of action for adiponectin within the adipocyte by which it enhances the metabolic flexibility of adipose tissue. Adiponectin overexpression from the liver is dramatically different from adiponectin overexpression from the adipocyte. In order to achieve the remarkable degree of """"""""metabolic flexibility"""""""" that adipocyte-specific overexpression achieves, we postulate that there is an intracellular mechanism of action that ensures enhanced differentiation potential, increased glyceroneogenesis, improvements in vascularization and enhanced susceptibility to ?3 adrenergic action. Using a combination of novel transgenic models and in vitro biochemistry we will put this hypothesis to a test. SA 3) Identify additional intracellular steps that lead to the assembly/maturation of adiponectin and effective release from adipocytes. We have identified Erp44 and Ero1 as critical factors for the assembly of adiponectin. We would like to identify additional critical players in this complex set of reactions, and establish the role of the Unfolded Protein Response (a process frequently upregulated in obese adipose tissue) in the maturation process. Combined, these studies should provide significant new insights into the physiology of this protein. The proposed lowering of ceramide levels is an attractive novel mechanism with the potential to explain the insulin-sensitizing, anti-apoptotic, pro-angiogenic and anti-inflammatory properties that have been attributed to adiponectin.

Public Health Relevance

Adiponectin is an adipocyte-derived factor exerting a vast array of beneficial effects on metabolically active cells. Even though we appreciate the strong correlations of elevated adiponectin levels with improvements in insulin-sensitivity, reduced inflammation and enhanced survival of many cell types, there is no known unifying mechanism that can explain the underlying principles leading to the metabolic enhancements generally seen with elevated adiponectin levels. A better understanding of this mechanism will highlight novel therapeutic avenues for the treatment of obesity, diabetes and cardiovascular disease.

National Institute of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Research Project (R01)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-EMNR-B (02))
Program Officer
Haft, Carol R
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of Texas Sw Medical Center Dallas
Internal Medicine/Medicine
Schools of Medicine
United States
Zip Code
Udit, Swalpa; Burton, Michael; Rutkowski, Joseph M et al. (2017) Nav1.8 neurons are involved in limiting acute phase responses to dietary fat. Mol Metab 6:1081-1091
Tanowitz, Herbert B; Scherer, Philipp E; Mota, Maria M et al. (2017) Adipose Tissue: A Safe Haven for Parasites? Trends Parasitol 33:276-284
Holland, William L; Xia, Jonathan Y; Johnson, Joshua A et al. (2017) Inducible overexpression of adiponectin receptors highlight the roles of adiponectin-induced ceramidase signaling in lipid and glucose homeostasis. Mol Metab 6:267-275
Ghaben, Alexandra L; Scherer, Philipp E (2017) Pas de Deux: Glucagon and Thyroid Hormone Moving in Perfect Synchrony. Circ Res 120:762-764
An, Yu A; Sun, Kai; Joffin, Nolwenn et al. (2017) Angiopoietin-2 in white adipose tissue improves metabolic homeostasis through enhanced angiogenesis. Elife 6:
Deng, Yingfeng; Wang, Zhao V; Gordillo, Ruth et al. (2017) An adipo-biliary-uridine axis that regulates energy homeostasis. Science 355:
Dufurrena, Quinn; Amjad, Farhad M; Scherer, Philipp E et al. (2017) Alterations in pancreatic ? cell function and Trypanosoma cruzi infection: evidence from human and animal studies. Parasitol Res 116:827-838
Jun, Jonathan C; Devera, Ronald; Unnikrishnan, Dileep et al. (2017) Adipose HIF-1? causes obesity by suppressing brown adipose tissue thermogenesis. J Mol Med (Berl) 95:287-297
Park, Jiyoung; Kim, Min; Sun, Kai et al. (2017) VEGF-A-Expressing Adipose Tissue Shows Rapid Beiging and Enhanced Survival After Transplantation and Confers IL-4-Independent Metabolic Improvements. Diabetes 66:1479-1490
Crewe, Clair; An, Yu Aaron; Scherer, Philipp E (2017) The ominous triad of adipose tissue dysfunction: inflammation, fibrosis, and impaired angiogenesis. J Clin Invest 127:74-82

Showing the most recent 10 out of 191 publications