iNOS promotes hypothalamic insulin resistance associated with deregulation of energy balance and obesity in rodents

Sci Rep. 2017 Aug 23;7(1):9265. doi: 10.1038/s41598-017-08920-z.

Abstract

Inducible nitric oxide (iNOS)-mediated S-nitrosation of the metabolic signaling pathway has emerged as a post-translational modification that triggers insulin resistance in obesity and aging. However, the effects of S-nitrosation in controlling energy homeostasis are unknown. Thus, in the present study we aimed to evaluate the effects of S-nitrosation in insulin signaling pathway in the hypothalamus of rodents. Herein, we demonstrated that the intracerebroventricular infusion of the nitric oxide (NO) donor S-nitrosoglutathione (GSNO) promoted hypothalamic insulin signaling resistance and replicated the food intake pattern of obese individuals. Indeed, obesity induced S-nitrosation of hypothalamic IR and Akt, whereas inhibition of iNOS or S-nitrosation of insulin signaling pathway protected against hypothalamic insulin resistance and normalized energy homeostasis. Overall, these findings indicated that S-nitrosation of insulin signaling pathway is required to sustain hypothalamic insulin resistance in obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Energy Metabolism*
  • Homeostasis
  • Hypothalamus / drug effects
  • Hypothalamus / metabolism*
  • Insulin / metabolism
  • Insulin Resistance*
  • Male
  • Mice
  • Mice, Knockout
  • Nitric Oxide Donors / metabolism
  • Nitric Oxide Synthase Type II / metabolism*
  • Obesity / etiology*
  • Obesity / metabolism*
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats
  • Rodentia
  • S-Nitrosoglutathione / metabolism
  • S-Nitrosoglutathione / pharmacology
  • Signal Transduction

Substances

  • Insulin
  • Nitric Oxide Donors
  • S-Nitrosoglutathione
  • Nitric Oxide Synthase Type II
  • Proto-Oncogene Proteins c-akt