Pycnogenol modulates apoptosis by suppressing oxidative stress and inflammation in high glucose-treated renal tubular cells.

Abstract

Compelling evidence indicates that polyphenolic antioxidants protect against diabetic nephropathy. Pycnogenol is made up of flavonoids, mainly procyanidins and phenolic compounds, and is a known powerful antioxidant. Hyperglycemia is characteristic of diabetic nephropathy and induces renal tubular cell apoptosis. Thus, in this study, we used high glucose-treated renal tubular cells to investigate the protective action of pycnogenol against high glucose-induced apoptosis and diabetic nephropathy. We also sought to further delineate the underlying mechanisms elicited by oxidative stress and inflammation and suppressed by pycnogenol. Results show that pycnogenol significantly suppressed the high glucose-induced morphological changes and the reduction in cell viability associated with cytotoxicity. Bcl2/Bax protein levels indicated pycnogenol's anti-apoptotic effect against high glucose-induced apoptotic cell death. In addition, several key markers of oxidative stress and inflammation were measured for pycnogenol's beneficial effects. Results indicate pycnogenol's anti-oxidative and anti-inflammatory efficacy in suppressing lipid peroxidation, total reactive species (RS), superoxide ((·)O(2)), nitric oxide (NO(·)), peroxynitrite (ONOO(-)), pro-inflammatory inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and nuclear factor-kappa B (NF-κB) nuclear translocation. Based on these results, we conclude that pycnogenol's anti-oxidative and anti-inflammatory properties underlie its anti-apoptotic effects, suggesting further investigation of pycnogenol as a promising treatment against diabetic nephropathy.

• Authors: You Jung Kim, Young Ae Kim, Takako Yokozawa
• Journal: Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association (Food Chem Toxicol) Vol. 49 Issue 9 Pg. 2196-201 (Sep 2011) ISSN: 1873-6351 [Electronic] England
• PMID: 21689714 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2011 Elsevier Ltd. All rights reserved.

Chemical References

• Flavonoids
• Plant Extracts
• pycnogenols
• Glucose

Topics

• Apoptosis (drug effects)
• Flavonoids (pharmacology)
• Glucose (administration & dosage)
• Inflammation (prevention & control)
• Kidney Tubules (drug effects, metabolism)
• Oxidative Stress (drug effects)
• Plant Extracts