Activation of bombesin receptor Subtype-3 by [D-Tyr6,β-Ala11,Phe13,Nle14]bombesin6-14 increased glucose uptake and lipogenesis in human and rat adipocytes

Mol Cell Endocrinol. 2018 Oct 15:474:10-19. doi: 10.1016/j.mce.2018.01.028. Epub 2018 Jan 31.

Abstract

BRS-3 has an important role in glucose homeostasis. Its expression was reduced in skeletal muscle from obese and/or diabetic patients, and BRS-3 KO-mice developed obesity. In this work, focused on rat/human adipose tissue, BRS-3 gene-expression was lower than normal-levels in hyperlipidemic, type-2-diabetic (T2D), and type-1-diabetic rats and also in obese (OB) and T2D patients. Moreover, BRS-3 protein levels were decreased in diabetic rat and in obese and diabetic human fat pieces; but neither mutation nor even polymorphism in the BRS-3-gene was found in OB or T2D patients. Interestingly, in rat and human adipocytes, without metabolic alterations, [D-Tyr6,β-Ala11,Phe13,Nle14]bombesin6-14 -BRS-3-agonist-, as insulin, enhanced BRS-3 gene/protein expression, increased, PKB, p70s6K, MAPKs and p90RSK1 phosphorylation-levels, and induced a concentration-related stimulation of glucose transport, GLUT-4 membrane translocation and lipogenesis, exclusively mediated by BRS-3, and abolished by wortmannin, PD98059 or rapamacyn. These results confirm that BRS-3 and/or its agonist are a potential therapeutic tool for obesity/diabetes.

Keywords: Adipose tissue; BRS-3; Diabetes; GLUT-4; Glucose metabolism; obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adipocytes / drug effects
  • Adipocytes / metabolism*
  • Animals
  • Biological Transport / drug effects
  • Bombesin / pharmacology*
  • Gene Expression Regulation / drug effects
  • Glucose / metabolism*
  • Glucose Transporter Type 4 / metabolism
  • Humans
  • Insulin / pharmacology
  • Lipogenesis / drug effects*
  • Male
  • Phosphorylation / drug effects
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism
  • Rats, Wistar
  • Receptors, Bombesin / agonists
  • Receptors, Bombesin / genetics
  • Receptors, Bombesin / metabolism*

Substances

  • Glucose Transporter Type 4
  • Insulin
  • RNA, Messenger
  • Receptors, Bombesin
  • bombesin receptor subtype 3
  • Glucose
  • Bombesin