ABSTRACT
The effects of black rice anthocyanidins (BRACs) on retinal damage induced by photochemical stress are not well known. In the present study, Sprague-Dawley rats were fed AIN-93M for 1 week, after which 80 rats were randomly divided into two groups and treated with (n = 40) or without BRACs (n = 40) for 15 days, respectively. After treatment, both groups were exposed to fluorescent light (3,000 +/- 200 lux; 25degrees C), and the protective effect of dietary BRACs were evaluated afterwards. Our results showed that dietary BRACs effectively prevented retinal photochemical damage and inhibited the retinal cells apoptosis induced by fluorescent light (p < 0.05). Moreover, dietary BRACs inhibited expression of AP-1 (c-fos/c-jun subunits), up-regulated NF-kappaB (p65) expression and phosphorylation of IkappaB-alpha, and decreased Caspase-1 expression (p < 0.05). These results suggest that BRACs improve retinal damage produced by photochemical stress in rats via AP-1/NF-kappaB/Caspase-1 apoptotic mechanisms.
Subject(s)
Animals , Rats , Animal Feed/analysis , Anthocyanins/administration & dosage , Antioxidants/administration & dosage , Blotting, Western , Caspase 1/genetics , Diet , Dietary Supplements/analysis , I-kappa B Proteins/genetics , NF-kappa B/genetics , Neoplasm Proteins/genetics , Nucleocytoplasmic Transport Proteins/genetics , Oryza/chemistry , Proto-Oncogene Proteins c-fos/genetics , Proto-Oncogene Proteins c-jun/genetics , Rats, Sprague-Dawley , Real-Time Polymerase Chain Reaction , Retinal Diseases/etiology , Signal Transduction/drug effects , Transcription Factor AP-1/geneticsABSTRACT
Normal and streptozotocin-induced diabetic rats were intraperitonially injected with hibiscus anthocyanin [90 mg/Kg bw] and green tea epicatechin [60 mg/Kg bw] extracts daily for two weeks. In addition, normal and diabetic rats were force fed on high-fat diet for two weeks. Rats suffering from hypercholesterolemia were used for induction of diabetes mellitus and fed on a hypercholesterolemic diet for two weeks using non-diabetic hypercholesterolemic rats as positive control. At the end of the experiment, serum glucose insulin, adiponectin, nitric oxide and lipid profile were measured. Anthocyanin and epicatechin extracts significantly decreased the elevated levels of glucose, nitric oxide, triglycerides, total cholesterol and LDL-C in serum of diabetic rats, while adiponectin was slightly increased. The concentrations of serum glucose, nitric oxide, triglycerides, total cholesterol and LDL-C were greatly increased, while adiponectin level was significantly decreased in diabetic rats fed high-fat or high-cholesterol diets. These results indicate that increased nitric oxide and [or] decreased adiponectin in serum may result in increasing the glucose, triglycerides, total cholesterol and LDL-C levels in diabetic, hyperlipidemic and hypercholesterolemic rats