Alberto O. Chávez

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OBJECTIVE Fibroblast growth factor (FGF)-21 is highly expressed in the liver and regulates hepatic glucose production and lipid metabolism in rodents. However, its role in the pathogenesis of type 2 diabetes in humans remains to be defined. The aim of this study was to quantitate circulating plasma FGF-21 levels and examine their relationship with insulin(More)
beta-Cell dysfunction is an important factor in the development of hyperglycemia of type-2 diabetes mellitus, and pancreatic islet amyloidosis (IA) has been postulated to be one of the main contributors to impaired insulin secretion. The aim of this study was to evaluate the correlation of IA with metabolic parameters and its effect on islets of Langerhans(More)
This study was undertaken to test the hypothesis that short-term exposure (4 h) to physiological hyperinsulinemia in normal, healthy subjects without a family history of diabetes would induce a low grade inflammatory response independently of glycemic status. Twelve normal glucose tolerant subjects received a 4-h euglycemic hyperinsulinemic clamp with(More)
OBJECTIVE To quantitate insulin sensitivity in lean and obese nondiabetic baboons and examine the underlying cellular/molecular mechanisms responsible for impaired insulin action to characterize a baboon model of insulin resistance. RESEARCH DESIGN AND METHODS Twenty baboons received a hyperinsulinemic-euglycemic clamp with skeletal muscle and visceral(More)
The aim of this study was to measure mitochondrial reactive oxygen species (ROS) production directly from skeletal muscle biopsies obtained from obese insulin-resistant non-diabetic and type 2 diabetic participants. Ten lean healthy, ten obese non-diabetic and ten type 2 diabetic participants received a euglycaemic–hyperinsulinaemic clamp to measure whole(More)
Type 2 diabetes mellitus (T2DM) is characterized by defects in insulin action and insulin secretion. Although insulin resistance manifests early during the prediabetic state, a failing beta-cell function unable to overcome insulin resistance at target tissues determines the onset of T2DM. This review focuses on recent advances in the molecular mechanisms of(More)
TNF-α levels are increased in obesity and type 2 diabetes. The regulation of TNF-α converting enzyme (TACE) and its inhibitor, tissue inhibitor of metalloproteinase 3 (TIMP3), in human type 2 diabetes is unknown. We examined TACE/TIMP3 regulation: (1) in lean and obese normal glucose tolerant (NGT) individuals and in type 2 diabetes patients; (2) following(More)
UNLABELLED Non-alcoholic fatty liver disease (NAFLD) is characterized by accumulation of triglycerides (TG) in hepatocytes, which may also trigger cirrhosis. The mechanisms of NAFLD are not fully understood, but insulin resistance has been proposed as a key determinant. AIMS To determine the TG content and long chain fatty acyl CoA composition profile in(More)
Essential hypertension is an insulin resistant state. Early insulin signaling steps are impaired in essential hypertension and a large body of data suggests that there is a crosstalk at multiple levels between the signal transduction pathways that mediate insulin and angiotensin II actions. At the extracellular level the angiotensin converting enzyme (ACE)(More)
CONTEXT Mitochondrial dysfunction has been proposed as an underlying mechanism in the pathogenesis of insulin resistance and type 2 diabetes mellitus. OBJECTIVE To determine whether mitochondrial dysfunction plays a role in the free fatty acid (FFA)-induced impairment in insulin action in skeletal muscle of healthy subjects. DESIGN Eleven lean normal(More)