Iranian Journal of

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Background: Diabetic neuropathy is one of the most common complications of diabetes mellitus, which is associated with a decrease in the synthesis and transport of neurotrophins . The aim of present study was to investigate the effect of endurance training on gene expression of nerve growth factor (NGF) in the sensory spinal cord of rats with diabetic neuropathy. Methods: Twenty eight adult male Wistar rats in the body mass range of 326.3±8.4 gr, randomly assigned in to four groups: diabetic control, diabetic training, healthy control and healthy training. For inducing diabetic neuropathy, after twelve hours of food deprivation, intraperitoneal injection of STZ solution (45 mg/Kg) method was used. Two weeks after STZ injection, the endurance training protocol was performed for six weeks and Twenty four hours after the last training session, rats were sacrificed. Gene expression of NGF in rat spinal sensory segments were measured with Real time technique. In order to determine the significant differences between groups and Interaction independent variables two way anova and LSD post hoc test were used. Results: Endurance training, resulted in a significant increase in gene expression of NGF in the rats. Also, in compare with diabetic control, training led to significant decrease in blood glucose levels in diabetic training group. Conclusion: Increased physical activity and exercise can strongly affect pathological factors associated with diabetic neuropathy by increasing nerve growth factor. It is recommended that for prevention of neurological complications and treatment of diseases associated with diabets exercise training could be used as a non-pharmachological treatment.

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Background: Glycogen synthase kinase 3 beta is a key regulator of many signaling pathways. It is reported that Inhibition of this kinase results neuronal survival. Accordingly in this study we investigated the effect of endurance training on the gene expression of GSK-3β in the sensory areas of the spinal cord of male Wistar rats with diabetic neuropathy.

Methods: we randomly assigned 16 male Wistar rats into four groups: healthy control, healthy trained, neuropathy control, neuropathy trained. Intraperitoneal injection of a STZ (streptozotocin) solution (45 mg/kg) was used to induce diabetes. At two weeks after STZ injections, the mechanical allodynia and thermal hyperalgesia tests demonstrated the presence of diabetic neuropathy. A moderate endurance training protocol was performed for a six- week period. At 24 hours after the final training session, the rats were sacrificed and the L4-L6 sensory neurons of the spinal cord tissue were removed. GSK-3β mRNA expression was performed using real time-PCR.

Results: Statistical analysis shows that neuropathy trained experiences a decrease in gene expression in comparison to neuropathy control (P=0.02). On the other there was significant difference between healthy control and neuropathy control (P=0.02). However, there was no significant difference between healthy control and neuropathy trained.

Conclusion: we claim that endurance training will effectively decrease the expression of GSK-3β in the sensory areas of spinal cord of male Wistar rats with diabetic neuropathy. Endurance training as a non- pharmacotherapy strategy can modulate and return GSK-3β to approximate normal levels.

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Background: Diabetes causes nerve tissue damage and ultimately death of nerve cells, especially in important areas such as the hippocampus. It seems that exercise training and anti-inflammatory supplements can moderate this condition. Therefore, the aim of this study was to determine the effect of aerobic training exercise and L-carnitine consumption on the levels of hippocampus CNTF and CNTFR proteins in diabetic rat.
Methods: 45 Wistar rats between 250 to 300 gr were randomly divided into six groups, including healthy control groups, sham, diabetic control, diabetes + aerobic exercise, diabetes + L-carnitine supplementation and diabetes + aerobic exercise + L-carnitine supplementation. L-carnitine supplements were divided. Diabetic groups underwent subcutaneous injection of 55 mg / kg STZ. supplementary groups received 100 mg of L-carnitine per day orally. The aerobic exercise program was performed for 6 weeks and 5 days a week. The research variables were measured 24 hours after the last training session by the ELISA technics in the hippocampal tissue. The statistical method of one-way analysis of variance and Toki post –hoc test were used to analyze the data.
Results: The present study showed an significant increase in CNTF and CNTFR protein levels of hippocampal tissue after aerobic exercise and L-carnitine consumption (P = 0.001), which greater effect found in combination manner.
Conclusion: Due to the effect of aerobic exercise and L-carnitine supplementation alone and in interaction with each other on hippocampal tissue, the use of this method can be considered as maintaining neural tissue in diabetes.

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Background: Imbalanced production of adipokines as leptin and adiponectin in diabetic patients may lead to the development of metabolic complications. Therefore, the aim of this study was to determine the effects of 2-month of caffeine ingestion along with aerobic training on changes in serum leptin and adiponectin levels and leptin/adiponectin ratio (LAR) in type 2 diabetic men.
Methods: Thirty-two diabetic men participated in a quasi-experimental designs in the four groups for two-months period of a aerobic training (treadmill walking 3 times/week, 1.5 hour/session, 65-85% HRR) with and without caffeine ingestion (3 mg.kg^-1.day). Serum changes in leptin and adiponectin were measured during two phases (baseline and 24-hours after completing of the training program). Data were analyzed by one-way ANOVA and bonferroni's post-hoc test at level P≤0.05.
Results: Administration of two-months caffeine (CA) alone and combination with aerobic training (AT) were significantly could reduced and increased in leptin and adiponectin level, respectively (P=0.001). Thus, the combined group (AT+CA) effect were far more appropriate intervention in changing the studied indices (P=0.001). Also, the LAR method was notable reduced in all study groups, although these effects were more significantly in the combined group (AT+CA) (P=0.001).
Conclusion: It seems administration of caffeine supplementation and aerobic training for two-months have a positive effects on the improved relative of leptin and adiponectin levels as well as their ratio in diabetics, although the combination of these two variables has been shown to have far more dual effects.