ABSTRACT
Background: Traditional medicines with anti-diabetic effects are considered suitable supplements to treat diabetes. Among medicinal herbs, Stevia Rebaudiana Bertoni is famous for its sweet taste and beneficial effect in regulation of glucose. However, little is known about the exact mechanism of stevia in pancreatic tissue. Therefore, this study investigated the possible effects of stevia on pancreas in managing hyperglycemia seen in streptozotocin-induced Sprague-Dawley rats
Methods: Sprague-Dawley rats were divided into four groups including normoglycemic, diabetic and two more diabetic groups in which, one was treated with aquatic extract of stevia [400 mg/kg] and the other with pioglitazone [10 mg/kg] for the period of 28 days. After completion of the experimental duration, rats were dissected; blood samples and pancreas were further used for detecting biochemical and histopathological changes. FBS, TG, cholestrol, HDL, LDL, ALT and AST levels were measured in sera. Moreover, MDA [malondialdehyde] level, catalase activity, levels of insulin and PPARgamma mRNA expression were also measured in pancreatic tissue
Results: Aquatic extract of stevia significantly reduced the FBS, triglycerides, MDA, ALT, AST levels and normalized catalase activity in treated rats compared with diabetic rats [p<0.05]. In addition to this, stevia surprisingly, increased PPARgamma and insulin mRNA levels in treated rats [p<0.05]. Furthermore, stevia compensated for the histopathological damage in diabetic rats
Conclusion: It is concluded that stevia acts on pancreatic tissue to elevate the insulin level and exerts beneficial anti-hyperglycemic effects through the PPARgamma-dependent mechanism and stevia's antioxidant properties
ABSTRACT
Extracted sperm from the testis have poor motility. Moreover, their motility changes during their journey through epidydimis. Meanwhile, they face high concentration of L-carnitine. In addition, lactate dehydrogenase C[4] [LDH-C[4]] gene disorders has been shown to cause impaired sperm motility, leading to infertility in male mice. The aim of this study was to evaluate sperm motility and LDH-C[4] enzyme activity upon L-carnitine [LC] and Pentoxifylline [PTX] administrations in mice. We extracted testicular sperm of 48 mice and divided them into three equal parts. One part was incubated with Ham's F10 medium [control], the other parts were treated with Ham's F10 containing LC and PTX with a final concentration of 1.76 mM, for 30 min at room temperature. Sperm motility was assessed according to the World Health Organization [WHO] criteria. Sperm LDH-C[4] enzyme activity was measured by spectrophotometery method. Statistical analyses were performed using ANOVA and Fisher's LSD test, and a p-value less than 0.05 was considered as a statistically significant difference. Sperm motility increased after 30 min of incubation in LC- and PTX-treated group [p<0.001]. LC and PTX administrations showed a significant increase in the LDHC[4] enzyme activity of sperm compared to that of the controls after 30 min [P=0.04 and 0.01, respectively]. The effects of LC and PTX on motility of sperm can be explained by an increase in LDH-C[4] enzyme activity that may influence male fertility status. We suggest that LC as a non-toxic antioxidant is more suitable for use in assisted reproductive technique protocols than PTX
Subject(s)
Male , Animals, Laboratory , Carnitine , Pentoxifylline , L-Lactate Dehydrogenase , Isoenzymes , Spermatozoa/drug effects , Testis , Mice, Inbred BALB CABSTRACT
Melatonin, found in high concentrations in the pineal gland, organs within the digestive system and in some plants and fungi, acts as an antioxidant which decreases reactive oxygen species in streptozocin-induced diabetic rats, raises insulin secretion by the pancreatic [3-cells and increases the number of insulin receptors on hepatocyte membranes. The protective and therapeutic effects of melatonin feeding in streptozocin-induced diabetic rats were studied. Streptozocin administered rats were gavaged with melatonin, pre- and post-treatment, at a level of 5 mg/kg body weight daily for a period of 15 days. Levels of plasma glucose, cholesterol, triacylglycerol, oral glucose tolerance test, and some hepatic enzymes of carbohydrate metabolism including insulin inducible glucokinase, hexokinase and glucose 6-P dehydrogenase were measured using standard methods and compared with the values in normoglycemic and diabetic control groups. Both pre- and post-treatment of the Streptozocin administered rats with melatonin normalized plasma glucose, cholesterol, and triacylglycerol, improved oral glucose tolerance test and increased hepatic glucokinase, hexokinase and glucose 6-P dehydrogenase specific activities to the levels seen in normal rats. Melatonin pre-treatment prevents the injurious effects of Streptozocin in rats. In Streptozocin induced diabetic animals, post-treatment with this antioxidant normalizes both blood and liver constituents which were ameliorated by Streptozocin