Format

Send to

Choose Destination
J Nutr Biochem. 2015 Jul;26(7):704-12. doi: 10.1016/j.jnutbio.2015.01.009. Epub 2015 Mar 13.

Cocoa-rich diet ameliorates hepatic insulin resistance by modulating insulin signaling and glucose homeostasis in Zucker diabetic fatty rats.

Author information

1
Department of Metabolism and Nutrition, Institute of Food Science and Technology and Nutrition, Consejo Superior de Investigaciones Científicas, José Antonio Novais 10, Ciudad Universitaria, 28040 Madrid, Spain.
2
Department of Metabolism and Nutrition, Institute of Food Science and Technology and Nutrition, Consejo Superior de Investigaciones Científicas, José Antonio Novais 10, Ciudad Universitaria, 28040 Madrid, Spain; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, 28029 Madrid, Spain.
3
Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas, Instituto de Salud Carlos III, 28029 Madrid, Spain; Departamento de Bioquímica y Biología Molecular II, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain.
4
Department of Metabolism and Nutrition, Institute of Food Science and Technology and Nutrition, Consejo Superior de Investigaciones Científicas, José Antonio Novais 10, Ciudad Universitaria, 28040 Madrid, Spain. Electronic address: s.ramos@ictan.csic.es.

Abstract

Insulin resistance is the primary characteristic of type 2 diabetes and results from insulin signaling defects. Cocoa has been shown to exert anti-diabetic effects by lowering glucose levels. However, the molecular mechanisms responsible for this preventive activity and whether cocoa exerts potential beneficial effects on the insulin signaling pathway in the liver remain largely unknown. Thus, in this study, the potential anti-diabetic properties of cocoa on glucose homeostasis and insulin signaling were evaluated in type 2 diabetic Zucker diabetic fatty (ZDF) rats. Male ZDF rats were fed a control or cocoa-rich diet (10%), and Zucker lean animals received the control diet. ZDF rats supplemented with cocoa (ZDF-Co) showed a significant decrease in body weight gain, glucose and insulin levels, as well as an improved glucose tolerance and insulin resistance. Cocoa-rich diet further ameliorated the hepatic insulin resistance by abolishing the increased serine-phosphorylated levels of the insulin receptor substrate 1 and preventing the inactivation of the glycogen synthase kinase 3/glycogen synthase pathway in the liver of cocoa-fed ZDF rats. The anti-hyperglycemic effect of cocoa appeared to be at least mediated through the decreased levels of hepatic phosphoenolpyruvate carboxykinase and increased values of glucokinase and glucose transporter 2 in the liver of ZDF-Co rats. Moreover, cocoa-rich diet suppressed c-Jun N-terminal kinase and p38 activation caused by insulin resistance. These findings suggest that cocoa has the potential to alleviate both hyperglycemia and hepatic insulin resistance in type 2 diabetic ZDF rats.

KEYWORDS:

Cocoa; Glucose homeostasis; Glucose tolerance; Insulin resistance; Insulin signaling pathway; Type 2 diabetic ZDF rats

PMID:
25814291
DOI:
10.1016/j.jnutbio.2015.01.009
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center