Naringenin ameliorates streptozotocin-induced diabetic rat renal impairment by downregulation of TGF-ß1 and IL-1 via modulation of oxidative stress correlates with decreased apoptotic events.

CONTEXT: Naringenin, a flavonone and a nutritive antioxidant which is mostly obtained from grapefruit, orange or tomato skin, has been extensively studied due to its radical scavenging activity. OBJECTIVE: The present study investigates the protective effect of naringenin on rat kidney after streptozotocin-induced diabetes. MATERIALS AND METHODS: Sixty male Wistar rats were divided into six groups. Diabetes was induced by a single intraperitoneal injection of streptozotocin (50 mg/kg) in groups II, III and IV. Naringenin 5 mg/kg body weight was given to groups III and V, but 10 mg/kg was given to groups IV and VI, orally once a day for 10 weeks. After which all animals were sacrificed, and the biochemical, histopathological, immunohistochemical and apoptotic assays were conducted. RESULTS: Naringenin treatment with 5 and 10 mg/kg significantly decreased (p < 0.05) the serum biochemical parameters, elevated tissue malondialdehyde levels and increased (p < 0.01) the reduced superoxide dismutase, catalase and reduced glutathione enzyme activities in the diabetic kidney. Diabetes-induced naringenin-treated groups showed an improved histology and revealed a significant reduction in apoptosis activity (7.2 ± 0.01 and 1.8 ± 0.05) and in expression of TGF-ß1 (18.9 ± 3.4 and 10.2 ± 2.1) at a dose of 5 and 10 mg/kg, respectively. Similarly, in contrast to the diabetic group, a significant difference was observed in the IL-1 expression (15.68 ± 4.3) in 5 mg/kg and (9.85 ± 2.1) in 10 mg/kg naringenin-treated groups. CONCLUSION: Naringenin acts as a protective agent in diabetic renal impairment by altering oxidative stress, modulation of cytokines expression and apoptotic events.

Ferulic acid in the treatment of post-diabetes testicular damage: relevance to the down regulation of apoptosis correlates with antioxidant status via modulation of TGF-ß1, IL-1ß and Akt signalling.

The aim of this study was to investigate the protective effect of ferulic acid at different doses (50 mg kg(-1) alternative day and 50 mg kg(-1) daily) on the streptozotocin (STZ)-induced post-diabetes rat testicular damage. Diabetes was induced by a single intraperitoneal injection of STZ (50 mg/kg). Rats treated with ferulic acid were given once a day orally for 10 weeks, starting 3 days after STZ injection. Testis tissue and blood samples were collected for investigating biochemical analysis, antioxidant status, sperm parameters, and histopathological, immunohistochemical and apoptotic studies. Treatment with ferulic acid to diabetic rats significantly improved the body weight, testis weight, serum insulin level, serum testosterone level and sperm parameters (viability, motility and count). Histopathological study also revealed that ferulic acid-treated diabetic rats showed an improved histological appearance. Our data indicated that significant reduction in the activity of apoptosis by using terminal deoxyuridine triphosphate nick end-labelling and reduced expression of transforming growth factor-ß1 and interleukin-1ß in the testis tissue of ferulic acid-treated diabetic rats. Conversely, it was also revealed that ferulic acid-treated diabetic rats markedly enhanced the serine/threonine protein kinase protein expression in the testis tissue. Our result suggests that ferulic acid inhibits testicular damage in diabetic rats by declining oxidative stress.

Treatment with ferulic acid to rats with streptozotocin-induced diabetes: effects on oxidative stress, pro-inflammatory cytokines, and apoptosis in the pancreatic ß cell.

In the present study, we aimed to investigate the protective effect of ferulic acid at different doses (50 mg/kg alternative day and 50 mg/kg daily) on diabetic rats and to explore the interrelationship between oxidative stress and cytokines correlates with apoptotic events in pancreatic tissue. Male Wistar rats were rendered diabetic by a single intraperitoneal injection of streptozotocin (60 mg/kg body weight). Ferulic acid was administered orally for 8 weeks. At the end of the study, all animals were sacrificed. Blood samples were collected for the biochemical estimations and pancreas was isolated for antioxidant status, histopathological, immunohistochemical, and apoptotic studies. Treatment with ferulic acid to diabetic rats significantly improved blood glucose, serum total cholesterol, triglycerides, creatinine, urea, and albumin levels toward normal. Furthermore, decrement of the elevated lipid peroxidation levels and increment of the reduced superoxide dismutase, catalase, and reduced glutathione enzyme activities in pancreatic tissues were observed in ferulic acid-treated groups. Ferulic acid-treated rats in the diabetic group showed an improved histological appearance. Our data also revealed a significant reduction in the activity of apoptosis using terminal dUTP nick end-labeling and reduced expression of TGF-ß1 and IL-1ß in the pancreatic ß-cell of ferulic acid-treated rats. Treatment with ferulic acid daily doses produced a significant result compared to alternative dose. Collectively our results suggested that ferulic acid acts as a protective agent in diabetic rats by altering oxidative stress, expression of pro-inflammatory cytokines and apoptosis.