METHOD: Neonatal streptozotocin-induced non-obese type 2 diabetic rats were treated with a methanolic extract of EO (250 or 500 mg/kg) for 28 days, and blood glucose, serum insulin, and plasma antioxidant status were measured. Insulin and glucagon immunostaining and morphometry were performed in pancreatic section, and liver TBARS and GSH levels were measured. Additionally, EA was tested for glucose-stimulated insulin secretion and glucose tolerance test.
RESULTS: Treatment with EO extract resulted in a significant decrease in the fasting blood glucose in a dose- and time-dependent manner in the diabetic rats. It significantly increased serum insulin in the diabetic rats in a dose-dependent manner. Insulin-to-glucose ratio was also increased by EO treatment. Immunostaining of pancreas showed that EO250 increased β-cell size, but EO500 increased β-cells number in diabetic rats. EO significantly increased plasma total antioxidants and liver GSH and decreased liver TBARS. EA stimulated glucose-stimulated insulin secretion from isolated islets and decreased glucose intolerance in diabetic rats.
CONCLUSION: Ellagic acid in EO exerts anti-diabetic activity through the action on β-cells of pancreas that stimulates insulin secretion and decreases glucose intolerance.
OBJECTIVE: To examine the effects of metformin on parameters involved in testicular lactate production, transport/utilisation, and sexual behaviour in diabetic state.
METHODS: Male Sprague-Dawley rats were assigned into normal control (NC), diabetic control (DC), and metformin-treated diabetic group (n = 6/group). Metformin (300 mg/kg b.w./day) was administrated orally for 4 weeks.
RESULTS: Intra-testicular glucose and lactate levels, and lactate dehydrogenase (LDH) activity increased, while the mRNA transcript levels of genes responsible for testicular glucose and lactate transport/utilisation (glucose transporter 3, monocarboxylate transporter 4 (MCT4), MCT2, and LDH type C) decreased in DC group. Furthermore, penile nitric oxide increased, while cyclic guanosine monophosphate decreased, with impaired sexual behaviour in DC group. Treatment with metformin improved these parameters.
CONCLUSIONS: Metformin increases testicular lactate transport/utilisation and improves sexual behaviour in diabetic state.
METHODS: Adult male rats with streptozotocin-nicotinamide-induced diabetes were given 50, 100 or 200 mg/kg body weight VVSEE orally for 28 days. At the end of the treatment, body weights were determined, and the blood was collected for analyses of fasting blood glucose, insulin and liver enzyme levels. Following sacrifice, livers were harvested and their wet weights and glycogen contents were measured. Histologic appearances of the livers were observed under light microscopy, and the expression and distribution of inflammatory, apoptosis and proliferative markers in the livers were identified by molecular biologic techniques.
RESULTS: Treatment of rats with diabetes by VVSEE attenuates decreased body weight, liver weight and liver glycogen content. Additionally, increases in fasting blood glucose levels and liver enzyme levels and decreases in serum insulin levels were ameliorated. Lesser histopathologic changes were also observed: decreased inflammation and apoptosis, as indicated by decreased levels of inflammatory markers (TNF-α, NF-Kβ, IKK-β, IL-6, IL-1β) and apoptosis markers (caspase-3, caspase-9 and Bax). VVSEE treatment induces increase in hepatocyte regeneration, as indicated by increased PCNA and Ki-67 distribution in the livers of rats with diabetes. Several molecules identified in VVSEE via gas chromatography mass spectrometry might contribute to these effects.
CONCLUSIONS: The anti-inflammatory, anti-apoptotic and pro-proliferative effects of VVSEE could account for its hepatoprotective actions in diabetes.
MATERIAL AND METHODS: A single dose of streptozotocin (45mg/kg body weight, iv) was used to induced diabetes in male Sprague Dawley rats which were then divided into two groups: Diabetic control (DC) and HSL-treated diabetic (DR) group. Normal rats were divided into normal control (NC), HSL-treated control (NR). Aqueous calyxes extract of HSL (100mg/kg/day, orally) was given for 28 consecutive days in the treated group. Weight, biochemical and histopathological (light and electron microscopic) parameters were compared in all groups.
RESULTS: Supplementation of HSL significantly lowered the level of fasting blood glucose and increased plasma insulin level in DR group compared to DC group (p<0.05). Alanine aminotransaminases and aspartate aminotransferase enzymes level were found to be significantly reduced in DR compared to DC. Microscopic examination demonstrated destruction of the liver architecture, cytoplasmic vacuolation of the hepatocytes and signs of necrosis in diabetic rats. Moreover, dilatation and congestion of blood vessels with leucocytes adherence were detected. Ultrastructural study using electron microscope showed homogeneous substance accumulation in nuclear chromatin, a decrease of organelles and mitochondrial degeneration in the diabetic rats.
CONCLUSION: Administration of HSL in diabetic rats causes significant decrease in hepatocyte destruction and prevented the changes associated with the diabetic condition. Thus, our findings provide a scientific rationale for the use of HSL as promising agent in preventing liver injury in diabetes.
METHODS: Thirty-two Sprague-Dawley male rats were randomly allocated into four groups (n=8): control, diabetes mellitus (DM) rats and diabetic rats treated with ifenprodil at a lower dose (0.5 μg/day) (I 0.5) or higher dose (1.0 μg/day) (I 1.0). DM was induced by a single injection of streptozotocin at 60 mg/kg on day 0 of experimentation. Diabetic status was assessed on day 3 of the experimentation. The responses on both tactile and thermal stimuli were assessed on day 0 (baseline), day 14 (pre-intervention), and day 22 (post-intervention). Ifenprodil was given intrathecally for 7 days from day 15 until day 21. On day 23, 5% formalin was injected into the rats' hind paw and the nociceptive responses were recorded for 1 hour. The rats were sacrificed 72 hours post-formalin injection and an analysis of the spinal NR2B expression was performed.
RESULTS: DM rats showed a significant reduction in pain threshold in response to the tactile and thermal stimuli and higher nociceptive response during the formalin test accompanied by the higher expression of phosphorylated spinal NR2B in both sides of the spinal cord. Ifenprodil treatment for both doses showed anti-allodynic and anti-nociceptive effects with lower expression of phosphorylated and total spinal NR2B.
CONCLUSION: We suggest that the pain process in the streptozotocin-induced diabetic rat that has been modulated is associated with the higher phosphorylation of the spinal NR2B expression in the development of PDN, which is similar to other models of neuropathic rats.
MATERIALS AND METHODS: Six control and five DM Wistar rats were evaluated. DM was induced at 11 weeks of age using streptozotocin (STZ; 60 mg/kg, intraperitoneal). Animals were monitored up to 38 weeks of age, when plasma glucose, lipid profile, and markers specific for systemic inflammation, endothelial dysfunction, and oxidative stress were measured. The amount of fat within the aortic wall was assessed semiquantitatively using Oil Red O staining.
RESULTS: Diabetic rats presented significantly higher plasma glucose (p < 0.001), total cholesterol and triglycerides (both p = 0.02), high-sensitivity C-reactive protein (p = 0.01), and vascular endothelial growth factor (p = 0.04) levels, and significantly lower interleukin-10 (p = 0.04), superoxide dismutase (p < 0.01), and glutathione peroxidase (p = 0.01) levels than the control rats. Mild (grade 1) atherosclerotic lesions were observed in the aortic wall of 80% of the diabetic rats and in none of the control rats.
CONCLUSIONS: This study presents a STZ-induced type 1 DM rat model with one of the longest follow-ups in the literature. In this model, long-term DM created a highly pro-atherogenic environment characterised by hyperglycemia, dyslipidemia, systemic inflammation, endothelial dysfunction, and oxidative stress that resulted in the development of early aortic atherosclerotic lesions.
MATERIALS AND METHODS: Diabetic ADSCs were treated with DFO and compared to normal and non-treated diabetic ADSCs for expression of HIF-1α, VEGF, FGF-2 and SDF-1, at mRNA and protein levels, using qRT-PCR, western blotting and ELISA assay. Activity of matrix metalloproteinases -2 and -9 were measured using a gelatin zymography assay. Angiogenic potential of conditioned media derived from normal, DFO-treated and non-treated diabetic ADSCs were determined by in vitro (in HUVECs) and in vivo experiments including scratch assay, three-dimensional tube formation testing and surgical wound healing models.
RESULTS: DFO remarkably enhanced expression of noted genes by mRNA and protein levels and restored activity of matrix metalloproteinases -2 and -9. Compromised angiogenic potential of conditioned medium derived from diabetic ADSCs was restored by DFO both in vitro and in vivo experiments.
CONCLUSION: DFO preconditioning restored neovascularization potential of ADSCs derived from diabetic rats by affecting the HIF-1α pathway.