The effect Aerobic Exercise on the level of expression of Toll-like receptor 4 and inflammatory mediators in the sensory spinal cord of Male Rats with diabetic neuropathic pain

Document Type : Original Article


1 Shahid Chamran University of Ahwaz - Faculty of Physical Education and Sport Sciences - Sports Physiology Department

2 Department of Sport Physiology, Faculty of Physical Education and Sports Science, Ahwaz Shahid Chamran University, Ahvaz, Iran

3 Department of Physiology, Faculty of Medicine, Ahwaz Jundishapur University of Medical Sciences, Ahwaz, Iran

4 dr


Background: Increased expression of TLR4 in the nervous system is one of the factors involved in the pathophysiology of Diabetic Peripheral Neuropathy. The purpose of this study was to determine the effect of aerobic training on the expression of TLR4 gene and inflammatory mediators in the sensory spinal cord of male rats with DPN
Methods: 40 male rats with weight(220 ± 2.2 g) were divided into four groups: diabetic neuropathy, diabetic neuropathy training, healthy control training and healthy control. Diabetes was induced by STZ injection. After confirming the development of conditions for DPN by behavioral tests, exercise groups performed 6 weeks of continuous aerobic exercise on treadmill. The level of expression of TLR4, TNF-α and IL-1β genes in sensory neurons of spinal cord L4-L6 was measured by Real-Time PCR technique. Two-way ANOVA and post-hoc LSD test were used for statistical analysis.
Results: the expression of TLR4, TNF-α and IL-1β genes in the diabetic neuropathy training group was significantly lower than the diabetic neuropathy group (P <0.05). Also, there was a significant difference between healthy control groups and diabetic neuropathy and the gene expression in the diabetic neuropathy group was increased (P <0.05).
Conclusion:Endurance training can reduce the expression of TLR4 gene and inflammatory markers in the sensory part of the spinal cord and improve the sensitivity of the nosepectors to painful factors. Therefore, it is suggested that endurance training be used as a non-prescriptive therapeutic intervention for diabetic patients to reduce neuropathic pain.


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