Accelerated fat cell aging links oxidative stress and insulin resistance in adipocytes

J Biosci. 2013 Mar;38(1):113-22. doi: 10.1007/s12038-012-9289-0.

Abstract

Telomere shortening is emerging as a biological indicator of accelerated aging and aging-related diseases including type 2 diabetes. While telomere length measurements were largely done in white blood cells, there is lack of studies on telomere length in relation to oxidative stress in target tissues affected in diabetes. Therefore, the aim of this study is to induct oxidative stress in adipocytes and to test whether these adipocytes exhibit shortened telomeres, senescence and functional impairment. 3T3-L1 adipocytes were subjected to oxidative stress and senescence induction by a variety of means for 2 weeks (exogenous application of H2O2, glucose oxidase, asymmetric dimethylarginine (ADMA) and glucose oscillations). Cells were probed for reactive oxygen species generation (ROS), DNA damage, mRNA and protein expression of senescent and pro-inflammatory markers, telomere length and glucose uptake. Compared to untreated cells, both ROS generation and DNA damage were significantly higher in cells subjected to oxidative stress and senescence. Adipocytes subjected to oxidative stress also showed shortened telomeres and increased mRNA and protein expression of p53, p21, TNF alpha and IL-6. Senescent cells were also characterized by decreased levels of adiponectin and impaired glucose uptake. Briefly, adipocytes under oxidative stress exhibited increased ROS generation, DNA damage, shortened telomeres and switched to senescent/pro-inflammatory phenotype with impaired glucose uptake.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3T3-L1 Cells
  • Adipocytes / cytology
  • Adipocytes / drug effects*
  • Adipocytes / metabolism
  • Adiponectin / genetics
  • Adiponectin / metabolism
  • Animals
  • Arginine / analogs & derivatives
  • Arginine / pharmacology
  • Biomarkers / metabolism
  • Cell Differentiation
  • Gene Expression / drug effects
  • Glucose / metabolism
  • Glucose / pharmacology
  • Glucose Oxidase / metabolism*
  • Glucose Oxidase / pharmacology
  • Hydrogen Peroxide / pharmacology
  • Insulin Resistance / genetics*
  • Interleukin-6 / genetics
  • Interleukin-6 / metabolism
  • Mice
  • Oxidative Stress / drug effects*
  • Reactive Oxygen Species
  • Telomere / chemistry
  • Telomere / drug effects*
  • Telomere Shortening / drug effects*
  • Telomere Shortening / genetics
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / metabolism
  • Tumor Suppressor Protein p53 / genetics
  • Tumor Suppressor Protein p53 / metabolism
  • p21-Activated Kinases / genetics
  • p21-Activated Kinases / metabolism

Substances

  • Adiponectin
  • Adipoq protein, mouse
  • Biomarkers
  • Interleukin-6
  • Reactive Oxygen Species
  • Tumor Necrosis Factor-alpha
  • Tumor Suppressor Protein p53
  • N,N-dimethylarginine
  • Arginine
  • Hydrogen Peroxide
  • Glucose Oxidase
  • p21-Activated Kinases
  • Glucose