Increased renin production in mice with deletion of peroxisome proliferator-activated receptor-gamma in juxtaglomerular cells

Hypertension. 2010 Mar;55(3):660-6. doi: 10.1161/HYPERTENSIONAHA.109.138800. Epub 2010 Jan 11.

Abstract

We recently found that endogenous (free fatty acids) and pharmacological (thiazolidinediones) agonists of nuclear receptor Peroxisome proliferator-activated receptor (PPAR)gamma stimulate renin transcription. In addition, the renin gene was identified as a direct target of PPARgamma. The mouse renin gene is regulated by PPARgamma through a distal enhancer direct repeat closely related to consensus PPAR response element (PPRE). In vitro studies demonstrated that PPARgamma knockdown stimulated PPRE-driven transcription. These data predicted that deficiency of PPARgamma would upregulate mouse renin expression. Consistent with these observations knockdown of PPARgamma increased the transcription of a reporter gene driven by the mouse renin PPRE-like motif in vitro. To study the impact of PPARgamma on renin production in vivo, we used a cre/lox system to generate double-transgenic mice with disrupted PPARgamma locus in renin-producing juxtaglomerular (JG) cells of the kidney (RC-PPARgamma(fl/fl) mice). We provide evidence that PPARgamma expression was effectively reduced in JG cells of RC-PPARgamma(fl/fl) mice. Fluorescent immunohistochemistry showed stronger renin signal in RC-PPARgamma(fl/fl) than in littermate control RC-PPARgamma(wt/wt) mice. Renin mRNA levels and plasma renin concentration in RC-PPARgamma(fl/fl) mice were almost 2-fold higher than in littermate controls. Arterial blood pressure and pressure control of renal vascular resistance, which play decisive roles in the regulation of renin production were indistinguishable between RC-PPARgamma(wt/wt) and RC-PPARgamma(fl/fl) mice. These data demonstrate that the JG-specific PPARgamma deficiency results in increased mouse renin expression in vivo thus corroborating earlier in vitro results. PPARgamma appears to be a relevant transcription factor for the control of renin gene in JG cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood Pressure / physiology
  • Cell Line
  • Fluorescent Antibody Technique
  • Gene Expression Regulation / physiology
  • Hematocrit
  • Humans
  • Integrases / genetics
  • Juxtaglomerular Apparatus / physiology*
  • Luciferases / genetics
  • Mice
  • Mice, Knockout
  • PPAR gamma / genetics*
  • PPAR gamma / metabolism*
  • RNA, Messenger / metabolism
  • Renin / blood*
  • Renin / genetics*
  • Signal Transduction / physiology
  • Transcription, Genetic / physiology
  • Up-Regulation / physiology

Substances

  • PPAR gamma
  • RNA, Messenger
  • Luciferases
  • Cre recombinase
  • Integrases
  • Renin

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