Angiopoietins in Diabetic Nephropathy

Korean Journal of Nephrology 2007;26(3):311-319.

Eun-Young Lee, M.D.1, Hyo-Wook Gil, M.D.1 , Jong-Oh Yang, M.D.1, Jang-Hyun Koh, M.D.2 Choon-Hee Chung, M.D.2 and Sae-Yong Hong, M.D.1

Department of Internal Medicine and Clinical Research Institute¹
SoonChunHyang University Cheonan Hospital, Cheonan, Korea Department of Internal Medicine²
Yonsei University Wonju College of Medicine, Wonju, Korea

당뇨병성 신증에서 angiopoietins 유전자의 변화

이은영1 길효욱1 양종오1 고장현2 정춘희2 홍세용1

순천향대학교 천안병원 신장내과 및 임상의학연구소1, 연세대학교 원주의과대학 내과학교실2

Abstract

Purpose : It has been reported that angiopoietins and Tie-2 receptor play an important role in the maintenance of glomerular filtration barrier in various glomerulonephritis models. We studied the role of angiopoietins on renal injury in diabetes. Methods : In this study, we examined the changes of angiopoietin-1, angiopoietin-2, Tie-2 receptor, and nephrin expression in the experimental diabetic nephropathy and also determined whether these changes were modified by renoprotective intervention by angiotensin II receptor blocker, α-lipoic acid, and peroxisome proliferator activated receptor (PPAR)-agonist. Results : A marked increase in urinary albumin excretion and glomerular volume was observed in diabetic rats. Renal angiopoietin-2 and Tie-2 receptor expression were significantly higher in diabetic rats than in the control groups, with a significant reduction in renal angiopoietin-2 expression, albuminuria, and renal hypertrophy in angiotensin II receptor blocker-treated diabetic rats. And there was a significant reduction in renal Tie-2 expression and renal hypertrophy in α-lipoic acid-treated and PPAR-γ agonist-treated diabetic rats. Conclusion : These results demonstrate that the dysregulation of angiopoietins and Tie-2 receptor can lead to renal hypertrophy and albuminuria. Angiotensin II receptor blocker, α-lipoic acid, and PPAR-γ agonist attenuated these changes in angiopoietins and/or Tie-2 expression and prevented the development of albuminuria and renal hypertrophy in vivo.

Key Words: Angiopoietin-1, Angiopoietin-2, Diabetic nephropathy, Nephrin, Tie-2 receptor