Ishige okamurae Extract Suppresses Obesity and Hepatic Steatosis in High Fat Diet-Induced Obese Mice

Nutrients. 2018 Nov 20;10(11):1802. doi: 10.3390/nu10111802.

Abstract

Obesity is caused by the expansion of white adipose tissue (WAT), which stores excess triacylglycerol (TG), this can lead to disorders including type 2 diabetes, atherosclerosis, metabolic diseases. Ishige okamurae extract (IOE) is prepared from a brown alga and has anti-oxidative properties. We investigated the detailed mechanisms of the anti-obesity activity of IOE. Treatment with IOE blocked lipid accumulation by reducing expression of key adipogenic transcription factors, such as CCAAT/enhancer-binding protein alpha (C/EBPα) and peroxisome proliferator-activated receptor gamma (PPARγ), in 3T3-L1 cells. Administration of IOE to high fat diet (HFD)-fed mice inhibited body and WAT mass gain, attenuated fasting hyperglycemia and dyslipidemia. The obesity suppression was associated with reductions in expression of adipogenic proteins, such as C/EBPα and PPARγ, increases in expression of lipolytic enzymes, such as adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL), in WAT of HFD-fed mice. In addition, IOE-treated mice had lower hepatic TG content, associated with lower protein expression of lipogenic genes, such as diglyceride acyltransferase 1 (DGAT1), sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS). IOE treatment also reduced serum free fatty acid concentration, probably through the upregulation of β-oxidation genes, suggested by increases in AMPKα and CPT1 expression in WAT and liver. In summary, IOE ameliorates HFD-induced obesity and its related metabolic disease, hepatic steatosis, by regulating multiple pathways.

Keywords: 3T3-L1 cells; Ishige okamurae; hepatic steatosis; high fat diet; mice; obesity.

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / drug effects
  • Adipocytes / metabolism
  • Adipose Tissue / drug effects
  • Adipose Tissue / growth & development
  • Adiposity / drug effects
  • Animals
  • Anti-Obesity Agents
  • Antioxidants / administration & dosage*
  • Diet, High-Fat*
  • Fatty Acids / metabolism
  • Fatty Liver / prevention & control*
  • Gene Expression / drug effects
  • Lipid Metabolism / drug effects
  • Lipogenesis / drug effects
  • Lipogenesis / genetics
  • Liver / metabolism
  • Male
  • Mice
  • Mice, Inbred ICR
  • Mice, Obese
  • Obesity / etiology*
  • Obesity / prevention & control*
  • Oxidation-Reduction
  • Phaeophyceae / chemistry*

Substances

  • Anti-Obesity Agents
  • Antioxidants
  • Fatty Acids