Regulation of autophagy by tea polyphenols in diabetic cardiomyopathy.
- Author:
Hui ZHOU
1
;
Yan CHEN
1
;
Shu-Wei HUANG
2
;
Peng-Fei HU
2
;
Li-Jiang TANG
1
Author Information
- Publication Type:Journal Article
- Keywords: Tea polyphenol; Autophagy; Diabetic cardiomyopathy; Obesity; Lipid metabolism disorder
- MeSH: Animals; Autophagy; drug effects; Beclin-1; analysis; Blood Glucose; analysis; Body Weight; Diabetic Cardiomyopathies; drug therapy; pathology; physiopathology; Lipids; blood; Male; Myocardium; pathology; Polyphenols; pharmacology; Rats; Rats, Sprague-Dawley; Tea; chemistry
- From: Journal of Zhejiang University. Science. B 2018;19(5):333-341
- CountryChina
- Language:English
-
Abstract:
OBJECTIVE:To investigate the effect of tea polyphenols on cardiac function in rats with diabetic cardiomyopathy, and the mechanism by which tea polyphenols regulate autophagy in diabetic cardiomyopathy.
METHODS:Sixty Sprague-Dawley (SD) rats were randomly divided into six groups: a normal control group (NC), an obesity group (OB), a diabetic cardiomyopathy group (DCM), a tea polyphenol group (TP), an obesity tea polyphenol treatment group (OB-TP), and a diabetic cardiomyopathy tea polyphenol treatment group (DCM-TP). After successful modeling, serum glucose, cholesterol, and triglyceride levels were determined; cardiac structure and function were inspected by ultrasonic cardiography; myocardial pathology was examined by staining with hematoxylin-eosin; transmission electron microscopy was used to observe the morphology and quantity of autophagosomes; and expression levels of autophagy-related proteins LC3-II, SQSTM1/p62, and Beclin-1 were determined by Western blotting.
RESULTS:Compared to the NC group, the OB group had normal blood glucose and a high level of blood lipids; both blood glucose and lipids were increased in the DCM group; ultrasonic cardiograms showed that the fraction shortening was reduced in the DCM group. However, these were improved significantly in the DCM-TP group. Hematoxylin-eosin staining showed disordered cardiomyocytes and hypertrophy in the DCM group; however, no differences were found among the remaining groups. Transmission electron microscopy revealed that the numbers of autophagosomes in the DCM and OB-TP groups were obviously increased compared to the NC and OB groups; the number of autophagosomes in the DCM-TP group was reduced. Western blotting showed that the expression of LC3-II/I and Beclin-1 increased obviously, whereas the expression of SQSTM1/p62 was decreased in the DCM and OB-TP groups (P<0.05).
CONCLUSIONS:Tea polyphenols had an effect on diabetic cardiomyopathy in rat cardiac function and may alter the levels of autophagy to improve glucose and lipid metabolism in diabetes.
