Cardioprotective effects of grape seed proanthocyanidins extracts in streptozocin induced diabetic rats.

The aim of this study was to clarify whether grape seed proanthocyanidins extracts (GSPE) were therapeutic agents against diabetic cardiomyopathy. After diabetes was induced by STZ intravenously into the tail veins, GSPE (250 mg/kg body weight/d) were administrated for 24 weeks. Serum glucose, glycated hemoglobin (HbA1c), and advanced glycation end products (AGEs) were determined. Electronic microscopy was used to observe the changes of myocardial ultrastructure. Reverse transcription polymerase chain reaction (RT-PCR) was used to evaluate the receptor of advanced glycation end products (RAGE), nuclear factor-kappaB (NF-kappaB), and transforming growth factor-betal (TGF-betal) gene expression in myocardial tissue. GSPE significantly reduced the AGEs of diabetic rats (P < 0.05). After being treated by GSPE, the levels of RAGE, NF-kappaB, and TGF-beta1 mRNA transcription in the myocardial tissue of diabetic rats were reduced (P < 0.05), the number of degenerated mitochondria was decreased, and the preservation of the fine structure of the LV myocardium was improved. In conclusion, GSPE plays an important role against diabetic cardiomyopathy. With the decreasing of AGEs, it can ameliorate glycation-associated cardiac damage. This study may provide a new recognition of natural medicine for the treatment of diabetic cardiomyopathy.