Journal Articles

A Small Amount of Dietary Carbohydrate Can Promote the HFD-Induced Insulin Resistance to a Maximal Level

July 23, 2014

A Small Amount of Dietary Carbohydrate Can Promote the HFD-Induced Insulin Resistance to a Maximal Level. PlosOne, July 23, 2014. Shuang Mei equal contributor; Xuefeng Yang equal contributor; Huailan Guo; Haihua Gu; Longying Zha; Junwei Cai; Xuefeng Li; Zhenqi Liu; Brian J. Bennett; Ling He; Wenhong Cao. 

Author Affiliations:

  • Nutrition Research Institute at Kannapolis, Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
  • Department of Nutrition, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America; Department of Nutrition and Food Hygiene, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, P. R. China
  • Department of Nutrition, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America; Department of Preventive Medicine, Hubei University of Medicine, Shiyan, Hubei, P. R. China
  • Nutrition Research Institute at Kannapolis, Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America.
  • Nutrition Research Institute at Kannapolis, Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America, Department of Nutrition and Food Hygiene, South Medical University, Guangzhou, China
  • Department of Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China
  • Department of Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China
  • Department of Medicine, University of Virginia Health System, Charlottesville, Virginia, United States of America
  • Department of Human Genetics, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
  • Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
  • Nutrition Research Institute at Kannapolis, Department of Nutrition, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America, Department of Medicine, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, China, Department of Medicine (Endocrinology and Metabolism), Duke University School of Medicine, Durham, North Carolina, United States of America

 

Abstract

Both dietary fat and carbohydrates (Carbs) may play important roles in the development of insulin resistance. The main goal of this study was to further define the roles for fat and dietary carbs in insulin resistance. C57BL/6 mice were fed normal chow diet (CD) or HFD containing 0.1–25.5% carbs for 5 weeks, followed by evaluations of calorie consumption, body weight and fat gains, insulin sensitivity, intratissue insulin signaling, ectopic fat, and oxidative stress in liver and skeletal muscle. The role of hepatic gluconeogenesis in the HFD-induced insulin resistance was determined in mice. The role of fat in insulin resistance was also examined in cultured cells. HFD with little carbs (0.1%) induced severe insulin resistance. Addition of 5% carbs to HFD dramatically elevated insulin resistance and 10% carbs in HFD was sufficient to induce a maximal level of insulin resistance. HFD with little carbs induced ectopic fat accumulation and oxidative stress in liver and skeletal muscle and addition of carbs to HFD dramatically enhanced ectopic fat and oxidative stress. HFD increased hepatic expression of key gluconeogenic genes and the increase was most dramatic by HFD with little carbs, and inhibition of hepatic gluconeogenesis prevented the HFD-induced insulin resistance. In cultured cells, development of insulin resistance induced by a pathological level of insulin was prevented in the absence of fat. Together, fat is essential for development of insulin resistance and dietary carb is not necessary for HFD-induced insulin resistance due to the presence of hepatic gluconeogenesis but a very small amount of it can promote HFD-induced insulin resistance to a maximal level.

Comments are closed.

Connect With Us