Format

Send to

Choose Destination
Mol Nutr Food Res. 2015 Apr;59(4):597-609. doi: 10.1002/mnfr.201400492. Epub 2015 Feb 23.

Cocoa flavonoids protect hepatic cells against high-glucose-induced oxidative stress: relevance of MAPKs.

Author information

1
Department of Metabolism and Nutrition, Institute of Food Science and Technology and Nutrition (ICTAN), Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Universitaria, Madrid, Spain.

Abstract

SCOPE:

Oxidative stress plays a main role in the pathogenesis of type 2 diabetes mellitus. Cocoa and (-)-epicatechin (EC), a main cocoa flavanol, have been suggested to exert beneficial effects in type 2 diabetes mellitus because of their protective effects against oxidative stress and insulin-like properties. In this study, the protective effect of EC and a cocoa phenolic extract (CPE) against oxidative stress induced by a high-glucose challenge, which causes insulin resistance, was investigated on hepatic HepG2 cells.

METHODS AND RESULTS:

Oxidative status, phosphorylated mitogen-activated protein kinases (MAPKs), nuclear factor E2 related factor 2 (Nrf2) and p-(Ser)-IRS-1 expression, and glucose uptake were evaluated. EC and CPE regulated antioxidant enzymes and activated extracellular-regulated kinase and Nrf2. EC and CPE pre-treatment prevented high-glucose-induced antioxidant defences and p-MAPKs, and maintained Nrf2 stimulation. The presence of selective MAPK inhibitors induced changes in redox status, glucose uptake, p-(Ser)- and total IRS-1 levels that were observed in CPE-mediated protection.

CONCLUSION:

EC and CPE recovered redox status of insulin-resistant HepG2 cells, suggesting that the functionality in EC- and CPE-treated cells was protected against high-glucose-induced oxidative insult. CPE beneficial effects on redox balance and insulin resistance were mediated by targeting MAPKs.

KEYWORDS:

Antioxidant defences; Cocoa flavanols; HepG2 cells; Insulin resistance; Oxidative markers

PMID:
25594685
DOI:
10.1002/mnfr.201400492
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center