Therapeutic Potential of Pterostilbene and Resveratrol on Biomechanic, Biochemical, and Histological Parameters in Streptozotocin-Induced Diabetic Rats.

AIMS: The aim of this study was to investigate the effects of pterostilbene (PTS) (trans-3,5-dimethoxy-4'-hydroxystilbene) and resveratrol (RSV) (trans-3,5,4' trihydroxystilbene) applied at different doses for the treatment of streptozotocin- (STZ-) induced diabetic rats. MATERIALS AND METHODS: At the end of the 5-week experimental period, the right gastrocnemius muscles of the rats were examined biomechanically, while the left ones were examined histologically. In addition, blood glucose, serum insulin, and malondialdehyde (MDA) levels were analyzed in blood samples taken from the rats. RESULTS: The skeletal muscle isometric contraction forces, which showed a decrease with diabetes, were observed to increase with antioxidant applications. Blood glucose, serum insulin, and MDA levels in diabetic rats approached normal levels after applying PTS. When the electron microscopic images of the rat skeletal muscle were examined, those in the combination treatment group were observed to show a better enhancement in the skeletal muscle morphological structure compared to the other diabetic and treatment groups. CONCLUSION: According to the findings, we suggest that these antioxidant treatments might have good therapeutic nutraceutical potential for some muscle diseases that coexist with diabetes. These treatments should be comprehensively investigated in the future.

Impacts of ß-estradiol on intestinal injury in newborn rats.

OBJECTIVE: Necrotizing enterocolitis has been investigated and debated extensively in recent years; however, there is still no effective treatment. The aim of this study was thus to examine the effects of ß-estradiol on intestinal injury in rats. METHODS: Twenty-four newborn female rat pups were divided into three groups. In group 1 (sham), hypoxia-re-oxygenation was not performed. In group 2 (saline), the rats were injected with saline after hypoxia-re-oxygenation, and the process was repeated for 5 d. In group 3 (ß-estradiol treatment), the rats were subjected to hypoxia-re-oxygenation and then given ß-estradiol intraperitoneally once a day for 5 d. After these procedures, the terminal ileum was removed for analysis. RESULTS: Statistically significant differences in histological grades were found between groups 1 and 2 (p = 0.000), groups 1 and 3 (p = 0.028), and groups 2 and 3 (p = 0.021). There were also differences in TNF-α and IL-6 levels between groups 2 and 3 (p = 0.000 and p = 0.038, respectively) and between groups 1 and 2 (p = 0.000 and p = 0.000); there was no difference between groups 1 and 3 (p = 0.574 and p = 0.195, respectively). Electron microscopy examination revealed a decrease in lipid droplets at the apical cytoplasm of the columnar cells in group 2; in group 3, the absorption of the lipids as lipid droplets was similar to that of group 1. CONCLUSION: In this study, ß-estradiol was found to decrease the intensity of intestinal injury significantly by inhibiting TNF-α and IL-6.

Ultrastructural evaluation of the effect of N-acetylcysteine on methotrexate nephrotoxicity in rats.

The aim of this study is to investigate the possible protective effect of N-Acetylcysteine (NAC) against the likely methotrexate (MTX) toxicity on the kidney using ultrastructural together with biochemical data. Moreover, the immunohistochemical detection of Ki67 nuclear antigen is to be evaluated. Fifteen male Wistar albino rats, weighing 240-290 g, were divided into three equal groups: Rats receiving MTX alone, rats receiving MTX plus NAC treatment, and rats comprising the control group. MTX (18 mg/kg/day, body weight) in dissolved physiologic saline was administered intraperitoneally to rats during 3 days. For the MTX plus NAC group, N-Acetylcysteine (300 mg/kg/day, body weight) was administered together with MTX. At the end of the third day, all the rats were killed with cervical dislocation to obtain blood and tissue samples. Application of MTX principally induced prominent large vacuolization in the proximal convoluted tubule cells, and focal thickening in the glomerular basal lamina of some glomeruli. A decrease in tissue SOD (superoxide dismutase) and GSH-Px (glutathione peroxidase), and an increase in serum urea nitrogen and creatinine and in tissue MDA (malondialdehyde) levels were also seen in the MTX group. These changes were significantly reversed in the MTX-plus-NAC-treated group. Most of the vacuoles in the proximal convoluted tubule cells disappeared. Furthermore, an increase in antioxidant enzyme activities, a decrease in serum urea nitrogen and creatinine, and tissue MDA levels were all significant. Additionally, an increase in the number of Ki67 positive-stained cells in proximal tubules was also noted. In conclusion, NAC may be a promising substance against MTX-induced renal damage. It might be useful to use NAC supplementally to minimize MTX-induced nephrotoxicity.

Effects of sodium selenite and amiloride on calvarial calcification in closing small cranial defects.

OBJECT: Fresh autogenous bone graft is the most preferred osteoplastic material, whether the purpose is cosmetic, psychological, or for the protection of the brain. These grafts are not rejected and do not react immunologically. The aim of this study was to evaluate the efficacy of autogenous fat rolled with bone dust derived from the bur hole in closing small cranial defects. Additionally, the authors examined the morphological and biochemical effects of Na selenite and amiloride on calvarial calcification. METHODS: The study group consisted of 20 domestic pigs. These animals were randomly divided into 4 groups. A bur hole with a diameter of 10 mm was made at the right parietal region in all animals, and then the periosteum around the bur hole was cauterized following exposure of the dura mater. The dura was coagulated with bipolar cautery. Group 1 (controls): only a bur hole was opened, and it was then closed with a mixture of the bone dust that had been created during the opening of the bur hole and fat tissue that was taken from the animal's neck. Group 2 (amiloride): 1 nmol/g body weight of amiloride was applied subcutaneously within 15 minutes after closure of the bur hole with bone dust and fat, and then amiloride was applied once a day for 4 weeks. Group 3 (Na selenite): 30 nmol/g body weight of Na selenite was applied subcutaneously within 30 minutes after closure of the bur hole with bone dust and fat, and then Na selenite was applied once a day for 4 weeks. Group 4 (amiloride and Na selenite): 1 nmol/g body weight of amiloride was applied subcutaneously at 15 minutes, and 30 nmol/g body weight of Na selenite was applied subcutaneously at 30 minutes after closure of the bur hole with bone dust and fat, and these 2 injections were repeated once a day for 4 weeks. At the end of 4 weeks, the animals were anesthetized to evaluate the closure of the bur hole. Tissue samples were obtained for ultrastructural and biochemical examination. RESULTS: The defect was covered with diffuse connective tissue in the control group. Although multiple capillary vessels were present, the authors did not observe osteogenic differentiation. Histological examination of the second group revealed osteogenic changes. Although new matrix was formed, calcification was not detected. The authors observed fibroblast, collagen fibers, and dense connective tissue filled with capillary in the third group of pigs, which had undergone Na selenite application. Calcification was not detected in this group. Both connective and osteogenic tissue were observed in specimens obtained in the fourth group, which had undergone amiloride and Na selenite application. CONCLUSIONS: The authors experimentally evaluated the supplementary osteogenic effects of Na selenite and amiloride by using them separately and together. The findings seem promising as a lead-in to new studies in restoring cranial defects.

Regenerative effects of pulsed magnetic field on injured peripheral nerves.

Previous studies confirm that pulsed magnetic field (PMF) accelerates functional recovery after a nerve crush lesion. The contention that PMF enhances the regeneration is still controversial, however. The influence of a new PMF application protocol (trained PMF) on nerve regeneration was studied in a model of crush injury of the sciatic nerve of rats. To determine if exposure to PMF influences regeneration, we used electrophysiological recordings and ultrastructural examinations. After the measurements of conduction velocity, the sucrose-gap method was used to record compound action potentials (CAPs) from sciatic nerves. PMF treatment during the 38 days following the crush injury enhanced the regeneration. Although the axonal ultrastructures were generally normal, slight to moderate myelin sheath degeneration was noted at the lesion site. PMF application for 38 days accelerated nerve conduction velocity, increased CAP amplitude and decreased the time to peak of the CAP. Furthermore, corrective effects of PMF on. the abnormal characteristics of sensory nerve fibers were determined. Consequently, long-periodic trained-PMF may promote both morphological and electrophysiological properties of the injured nerves. In addition, corrective effects of PMF on sensory fibers may be considered an important finding for neuropathic pain therapy.