OBJECTIVES: To investigate the effect of metformin on the expression of testicular steroidogenesis-related genes, spermatogenesis, and fertility of male diabetic rats.
MATERIALS AND METHODS: Eighteen adult male Sprague Dawley rats were divided into three groups, namely normal control (NC), diabetic control (DC), and metformin-treated (300 mg/kg body weight/day) diabetic rats (D+Met). Diabetes was induced using a single intraperitoneal injection of streptozotocin (60 mg/kg b.w.), followed by oral treatment with metformin for four weeks.
RESULTS: Diabetes decreased serum and intratesticular testosterone levels and increased serum but not intratesticular levels of luteinizing hormone. Sperm count, motility, viability, and normal morphology were decreased, while sperm nuclear DNA fragmentation was increased in DC group, relative to NC group. Testicular mRNA levels of androgen receptor, luteinizing hormone receptor, cytochrome P450 enzyme (CYP11A1), steroidogenic acute regulatory (StAR) protein, 3β-hydroxysteroid dehydrogenase (HSD), and 17β-HSD, as well as the level of StAR protein and activities of CYP11A1, 3β-HSD, and 17β-HSD, were decreased in DC group. Similarly, decreased activities of epididymal antioxidant enzymes and increased lipid peroxidation were observed in DC group. Consequently, decreased litter size, fetal weight, mating and fertility indices, and increased pre- and post-implantation losses were recorded in DC group. Following intervention with metformin, we observed increases in serum and intratesticular testosterone levels, Leydig cell count, improved sperm parameters, and decreased sperm nuclear DNA fragmentation. Furthermore, mRNA levels and activities of steroidogenesis-related enzymes were increased, with improved fertility outcome.
DISCUSSION AND CONCLUSION: Diabetes mellitus is associated with dysregulation of steroidogenesis, abnormal spermatogenesis, and fertility decline. Controlling hyperglycemia is therefore crucial in preserving male reproductive function. Metformin not only regulates blood glucose level, but also preserves male fertility in diabetic state.
MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into 5 groups, namely: normal control (NC), diabetic control (DC), diabetic on 300 mg/kg b.w. MP, diabetic on 300 mg/kg b.w. metformin, and diabetic on MP and metformin combined therapy. Treatment was done orally for 4 weeks, and NC and DC groups received distilled water as vehicle.
KEY FINDINGS: Results showed increased fasting blood glucose and serum markers of hepatic lesion (aspartate aminotransferase, alkaline phosphatase, alanine aminotransferase and gamma-glutamyl transferase), increased hepatic lactate dehydrogenase activity, decreased hepatic superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase and glutathione reductase activities, increased immunoexpressions of nuclear factor kappa B, tumor necrosis factor-α, interleukin(IL)-1β and caspase-3, and decreased immunoexpressions of IL-10 and proliferating cell nuclear antigen in the liver of DC group. Histopathology of the liver revealed numerous hepatocytes with pyknotic nuclei and inflammatory infiltration, while periodic acid-schiff staining decreased in the liver of DC group. Treatment with MP attenuated these negative effects and was comparable to metformin. Furthermore, these effects were better attenuated in the combined therapy-treated diabetic rats.
SIGNIFICANCE: Malaysian propolis attenuates hepatic lesion in DM and exerts a synergistic protective effect with the anti-hyperglycemic medication, metformin.
METHODS: AE was administered to streptozotocin (STZ)-induced diabetic rats twice daily at three doses (1000, 500, and 250 mg/kg b.w.) for 12 days p.o. Several biochemical analyses and a histological study of the pancreas and liver were performed, accompanied by a cell culture assay.
RESULTS: As compared to diabetic control (DC), AE at the doses of 500 and 1000 mg/kg b.w. caused significant reduction (p < 0.05) of blood glucose, total cholesterol and triglycerides levels, with positive improvement of serum insulin levels. Interestingly, immunohistochemical staining of the pancreas suggested no β-cell regeneration, despite significant increase in insulin production. AE-treated groups, however, showed overall restoration of the hepatic histoarchitecture of STZ-induced liver damage, suggesting a possible hepatoprotective effect. The pancreatic effect of AE was further studied through RIN-5F cell culture, which revealed a positive stimulatory effect on insulin release at a basal glucose concentration (1.1 mM).
CONCLUSION: Nypa fruticans Wurmb. vinegar's aqueous extract exerts its antihyperglycaemic activity, at least in part, through insulin stimulatory and hepatoprotective effects.
METHODS: SLBH at 1 and 2g/kg/b.w. was given orally to streptozotocin (STZ)-nicotinamide-induced male diabetic rats for 28days. Metabolic parameters (fasting blood glucose-FBG and lipid profiles-LP and serum insulin) were measured by biochemical assays. Distribution and expression level of insulin, oxidative stress marker i.e. catalase, inflammatory markers i.e. IKK-β, TNF-α, IL-1β and apoptosis marker i.e. caspase-9 in the pancreatic islets were identified and quantified respectively by immunohistochemistry. Levels of NF-κβ in pancreas were determined by enzyme-linked immunoassay (ELISA).
RESULTS: SLBH administration to diabetic male rats prevented increase in FBG, total cholesterols (TC), triglyceride (TG) and low density lipoprotein (LDL) levels. However, high density lipoprotein (HDL) and serum insulin levels in diabetic rats receiving SLBH increased. Additionally, histopathological changes and expression level of oxidative stress, inflammation and apoptosis markers in pancreatic islets of diabetic rats decreased with increased expression level of insulin in the islets. LC-MS analysis revealed the presence of several compounds in SLBH that might be responsible for these effects.
CONCLUSIONS: SLBH has great potential to be used as agent to protect the pancreas against damage and dysfunction where these could account for its anti-diabetic properties.
EXPERIMENTAL APPROACH: 3H-deoxycytidine-labeled PGs (17 or 41 kDa) and 3H-deoxycytidine were administered intravenously to normal rats and streptozotocin-induced diabetic rats. The biodistribution of these compounds was determined over 24 h. Accumulation of PG in normal kidneys was also tracked using 5-(aminoacetamido) fluorescein (fluoresceinyl glycine amide)-labeled PG (PG-AF). To evaluate the potential of PGs in ferrying renal protective anti-oxidative stress compounds, the model drug 4-(2-aminoethyl)benzenesulfonyl fluoride hydrochloride (AEBSF) was conjugated to 41 kDa PG to form PG-AEBSF. PG-AEBSF was then characterized and evaluated for intracellular anti-oxidative stress efficacy (relative to free AEBSF).
RESULTS: In the normal rat kidneys, 17 kDa radiolabeled PG (PG-Tr) presents a 7-fold higher, while 41 kDa PG-Tr shows a 15-fold higher renal accumulation than the free radiolabel after 24 h post injection. The accumulation of PG-AF was primarily found in the renal tubular tissues at 2 and 6 h after an intravenous administration. In the diabetic (oxidative stress-induced) kidneys, 41 kDa PG-Tr showed the greatest renal accumulation of 8-fold higher than the free compound 24 h post dose. Meanwhile, the synthesized PG-AEBSF was found to inhibit intracellular nicotinamide adenine dinucleotide phosphate oxidase (a reactive oxygen species generator) at an efficiency that is comparable to that of free AEBSF. This indicates the preservation of the anti-oxidative stress properties of AEBSF in the conjugated state.
CONCLUSION/IMPLICATIONS: The favorable accumulation property of 41 kDa PG in normal and oxidative stress-induced kidneys, along with its capabilities in conserving the pharmacological properties of the conjugated renal protective drugs, supports its role as a potential renal targeting drug carrier.
METHODS: Blood and pancreas were collected from adult male diabetic rats receiving 28days treatment with VVSAE orally. Fasting blood glucose (FBG), glycated hemoglobin (HbA1c), insulin and lipid profile levels and activity levels of anti-oxidative enzymes (superoxide dismutase-SOD, catalase-CAT and glutathione peroxidase-GPx) in the pancreas were determined by biochemical assays. Histopathological changes in the pancreas were examined under light microscopy and levels of insulin, glucose transporter (GLUT)-2, tumor necrosis factor (TNF)-α, Ikkβ and caspase-3 mRNA and protein were analyzed by real-time PCR (qPCR) and immunohistochemistry respectively. Radical scavenging activity of VVSAE was evaluated by in-vitro anti-oxidant assay while gas chromatography-mass spectrometry (GC-MS) was used to identify the major compounds in the extract.
RESULTS: GC-MS analyses indicated the presence of compounds that might exert anti-oxidative, anti-inflammatory and anti-apoptosis effects. Near normal FBG, HbAIc, lipid profile and serum insulin levels with lesser signs of pancreatic destruction were observed following administration of VVSAE to diabetic rats. Higher insulin, GLUT-2, SOD, CAT and GPx levels but lower TNF-α, Ikkβ and caspase-3 levels were also observed in the pancreas of VVSAE-treated diabetic rats (p<0.05 compared to non-treated diabetic rats). The extract possesses high in-vitro radical scavenging activities.
CONCLUSION: In conclusions, administration of VVSAE to diabetic rats could help to protect the pancreas against oxidative stress, inflammation and apoptosis-induced damage while preserving pancreatic function near normal in diabetes.
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.