L-Carnitine supplementation increases expression of PPAR-γ and glucose transporters in skeletal muscle of chronically and acutely exercised rats.

In this study, the effects of L-Carnitine supplementation on the lipid peroxidation and expression of PPAR-γ and glucose transporters in the liver and muscles of chronically and acutely exercised rats were investigated. A total of 42 male Wistar Albino rats (8-week-old) were divided into six groups as follows: Control, L-Carnitine, Chronic Exercise (CE), Chronic Exercise + L-Carnitine, Acute Exercise (AE) and L-Carnitine + Acute Exercise. Chronic exercise consists of 30 m/min, 30 min/day, and 5 days/week for 6 weeks. Rats in the acute exercise groups were run on the treadmill at 30 m/min until exhaustion. L-Carnitine was given at the level of 300 mg per kilogram of diet for 6 weeks. There was no significant difference in the levels of serum ALT, AST, urea, creatinine and glucose levels between the exercise and L-Carnitine groups (P > 0.05). Cholesterol and triglyceride levels decreased by L- carnitine supplementation and chronic exercise in control groups but increased in the AE groups compared to the control group without reinforcement (P < 0.05). Serum, muscle, heart, and liver malondialdehyde (MDA) concentrations were lower in CE and higher in the AE groups (P < 0.001). However, L-Carnitine supplementation reduced MDA levels (P < 0.05). Liver and muscle PPAR-γ, liver GLUT-2 and muscle GLUT-4 mRNA expressions were lower in AE group than in all other groups (P < 0.001). Both chronic exercise and supplemental L-Carnitine increased liver and muscle PPAR-γ, GLUT-2 and GLUT-4 mRNA expression (P <0.05). As a result, although acute exercise increased oxidative stress, chronic exercise reduced oxidative stress by lowering lipid peroxidation level. L-Carnitine supplementation decreased oxidative stress and improved glucose and lipid metabolism by regulation of PPAR-γ, GLUT-2 and GLUT-4 mRNA expression in rats.

Histopathological evaluation of mesenchymal stem cells in the healing of anastomosed carotid arteries.

The objective of this study was to evaluate the influence of mesenchymal stem cells on the healing of experimental carotid artery anastomoses histopathologically. Twenty-four female Sprague-Dawley rats were used in this study. After random separation of the subjects into two groups, in both groups carotid arteries were transected and anastomosed in end-to-end fashion. Anastomoses were locally treated with 1 ml 0.09% NaCl, and 1 ml mesenchymal stem cell suspension (1×106 cells) in control and trial groups, respectively. Anastomoses were wrapped with an 8 mm sheet of surgicel and soaked with BioGlue in order to sequestrate the stem cells. After patencies were confirmed via Doppler USG, surgical site was closed with 2/0 silk sutures. Histopathological evaluation was carried out after 4 weeks. In respect to endothelial continuity, vessel patency (along with presence or absence of restenosis), integrities of internal and external elastic laminae, muscularis and adventitia; no statistically significant differences were present between the trial and control groups. In Trial and Control Groups, luminal thrombus was present in 8 (66.6%) and 3 (25%) of the 12 subjects, respectively. The difference was statistically significant (P < 0.05). Recanalization was present in 6 subjects in trial group; 1 subjects in Control Group, respectively. Our results suggest that local administration of mesenchyme stem cell does not have a positive influence on success of an anastomosis.

Electrophysiological and histopathological effects of mesenchymal stem cells in treatment of experimental rat model of sciatic nerve injury.

AIM: The aim of this study was to evaluate electrophysiological and histopathological effects of mesenchymal stem cells in treatment of sciatic nerve injury. MATERIAL AND METHODS: Thirty-two female Spraque-Dawley rat were used in this study. Eight rats were used as a reference group in electrophysiological analysis for evaluation of non-injured nerve recordings (Control Group). Twenty-four rats were used for experimental evaluation. Twelve rats were anastomosed without treatment with mesenchymal stem cells (Sham Group) and twelve other rats were anastomosed and treated with mesenchymal stem cells (Stem Cell Group). Surgicel and bioglue were used in anastomosed line in both Groups. Eight weeks after the surgery, electrophysiological evaluation of rats was performed and, then, rats were decapitated under anesthesia and specimens including sciatic nerves and anastomosed line were taken for histopathological evaluation. Electromyography and nerve conduction velocity testing and histopathological scoring including rate of Wallerian degeneration, and neuroma and scar formation were evaluated for both Groups. RESULTS: There were no statistically significant differences between Sham and Stem Cell Groups with respect to histopathological evaluation. However, nerve conduction velocity showed significant difference between groups (P = 0.001). Nerve conduction velocity was significantly improved in Stem Cell Group when compared to Sham Group. CONCLUSION: In this study, based on nerve conduction velocity data, it was concluded that treatment with mesenchymal stem cells during end-to-end anastomosis improves functional regeneration.