Abstract
Purpose: :
Adiponectin is a polypeptide hormone exclusively secreted from adipocytes. When it acts with its receptors, adipo R1 and R2, could stimulate AMP-activated protein kinase activity. Studies have showed that serum adiponectin were found to be positively correlated with the severity of diabetic retinopathy. Fenofibrate is a PPAR-α agonist. Recently FIELD and ACCORD eye Study showed that fenofibrate could reduce the risk of microvascular complications and development or progression of diabetic retinopathy. The purpose of this study is to investigate the effect of fenofibrate on the expression of adiponectin and its receptors in retina of rats with type 1 diabetes mellitus.
Methods: :
Type 1 diabetes mellitus was induced in Sprague-Dawley rats by intravenous injection of streptozotocin (STZ). Rats were randomly divided into 4 groups : the control group (C), the diabetes group (DM), the diabetes group treated with low-dosage fenofibrate (30 mg/kg/day), and the diabetes group treated with high-dosage fenofibrate (100 mg/kg/day). After 2 months treatment, the expression of adiponectin, adipo R1 and R2 in retina were determined by PCR, western blot and immunofluorescent stain. Aqueous humor and plasma adiponectin were determined by ELISA.
Results: :
The expression of mRNA and protein of adiponectin, adipoR1and R2 in the diabetic group were significant higher than the control group. Treatment of fenofibrate dose-dependently suppressed the expression of adiponectin, adipoR1and R2 compared with the non-treatment group. The suppressive effect of fenofibrate on adiponectin expression was confirmed by immunofluorescent stain. Aqueous humor and plasma adiponectin levels also decreased after fenofibrate treatment.
Conclusions: :
Treatment of fenofibrate could suppress the expression of adiponectin , adipo R1and R2 in retina of diabetic rats. The beneficial effect of fenofibrate on diabetic retina may be related its regulatory effect on adiponectin and its receptors.
Keywords: diabetic retinopathy