Effect of vitamins A, E, C and omega-3 fatty acids supplementation on the level of catalase and superoxide dismutase activities in streptozotocin-induced diabetic rats

Background: Since free radicals and antioxidant enzymes may play an important role in the development of diabetes, the present study was designed to assess the effect of supplementation with vitamins A, E and C and �-3 fatty acids on catalase and superoxide dismutase activity in streptozotocin (STZ)-induced diabetic rats. Methods: A total of 64 male Wistar rats weighing 250 g were divided into four groups as normal control, diabetic control, diabetic supplemented with vitamin A, E and C and diabetic supplemented with �-3 fatty acids. After four weeks the rats were anesthetized and catalase (CAT) and superoxide dismutase (SOD) activities were investigated in blood samples, liver and heart homogenates. Results: In diabetic rats, the activity levels of heart SOD (p < 0.001) and heart and liver CAT (p < 0.001) were significantly lower than in normal control rats. Supplementation with vitamins A, E and C significantly increased heart CAT (p = 0.05). No significant change was observed in diabetic rats supplemented with �-3 fatty acids. Conclusion: Supplementation with vitamins A, E and C and �-3 fatty acids was found to increase heart CAT activity in diabetic rats and they can be valuable candidates in the treatment of the complications of diabetes

Vitamin D suppresses proangiogenic factors in patients with ulcerative colitis: A randomized double blind placebo controlled clinical trial

Background: Angiogenesis and inflammation are involved in the pathogenesis of ulcerative colitis (UC). This study aimed to assess the effect of vitamin D on serum levels of proangiogenic factors, visfatin and vascular endothelial growth factor (VEGF), in patients with UC. Materials and methods: Ninety patients were randomized to receive either a single intramuscular injection of 300,000 IU vitamin D or normal saline. Visfatin, VEGF, and 25-hydroxyvitamin D 25(OH)D concentrations were assessed before and 90 days after the intervention. Results: There were no significant differences in visfatin and VEGF levels between the two groups following supplementation. In patients with vitamin D insufficiency, visfatin increase was significantly lower in the intervention versus placebo group. There was an inverse correlation between serum 25(OH)D and visfatin in the subgroup with vitamin D insufficiency. Conclusion: Vitamin D might be beneficial in decreasing proangiogenic factors such as visfatin in UC patients with low 25(OH)D levels. © 2020 Elsevier Lt

Evaluation of the protective effects of quercetin in biliary cirrhotic rats

Background: Biliary cirrhosis is a chronic disease marked by the progressive destruct-tion of liver. There is no known cure for this disease; however, medications may slow its progression. The present study was designed to investigate the effect of quercetin as a plant derived flavonoid on the hepatic injury reduction of biliary cirrhotic rats.Methods: Thirty male Sprague-Dawley rats aged 6-7 months were randomized into three groups of ten each. One group served as control (sham operated), while the other two groups underwent a complete bile-duct ligation (BDL). Four weeks after the opera-tion, serum bilirubin, alkaline phosphatase (ALP), alanine amino-transferase (ALT), and aspartate amino-transferase (AST) were measured in two BDL groups to confirm the occurrence of cirrhosis. Then one of the BDL groups received placebo and the other one injected intraperitoneally with 50mg/kg of quercetin once a day for a period of four weeks. At the end of the study, hepatic enzymes and serum bilirubin were measured again. Liver species were tested for histological characteristics.Results: Quercetin could decrease serum level of bilirubin (7.4&plusmn;0.9 vs. 8.9&plusmn;1.6 mg/dL; P<0.05), ALP (1387&plusmn;76.9 vs. 2273&plusmn;65.3 IU/L; P<0.001) and ALT (601.9&plusmn;38.1 vs. 644.8&plusmn;37.4 IU/L; P<0.05) compared to cirrhotic group. AST was higher in cirrhotic groups compared to control both in the 4th and 8th week. However, the difference between BDL and BDL+Q groups was not statistically significant. Quercetin decreased ALT/AST ratio, as an indicator of liver damage. No significant histological changes were observed in quercetin group.Conclusion: These data suggest that although quercetin did not change histological characteristics of liver, it could significantly decrease bilirubin, alkaline phosphatase and alanine amino-transferase, indicating less liver injury