• Users Online: 367
  • Home
  • Print this page
  • Email this page
Home About us Editorial board Ahead of print Current issue Search Archives Submit article Instructions Subscribe Contacts Login 
Year : 2015  |  Volume : 21  |  Issue : 3  |  Page : 115-124

Vitamin D protects diabetic rats from neuropathic changes by improving insulin sensitivity and upregulating vitamin D receptors

1 Department of Medical Physiology, Faculty of Medicine, Cairo University, Cairo, Egypt
2 Department of Biochemistry, Faculty of Medicine, Cairo University, Cairo, Egypt

Correspondence Address:
Ola M Tork
Department of Medical Physiology, Faculty of Medicine, Cairo University, 11451 Cairo
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/1687-4625.177819

Rights and Permissions

Background There is emerging evidence of neuroprotective roles for vitamin D. However, its role in the pathogenesis of type 2 diabetes mellitus (T2DM) and its exact mechanism of action in neuroprotection are still unclear. The present work was designed to examine the effect of vitamin D supplementation on insulin sensitivity and nerve conduction velocity with and without insulin treatment in a diabetic model. Materials and methods This study was carried out on 50 male adult rats. They were divided into five groups: a control group, a diabetic group, in which T2DM was induced; a diabetic insulin-treated group, in which diabetic rats were treated with insulin alone; a diabetic vitamin D-treated group, in which diabetic rats were treated with vitamin D alone; and finally, a diabetic with combined insulin and vitamin D treatment group. At the end of the experimental period, blood samples were obtained from all animals for measurement of serum glucose and insulin, together with the oxidative stress marker malondialdehyde (MDA) and inflammatory markers interleukins 1β and 10 (IL1β and IL10). Nerve conduction velocity was performed on a dissected sciatic nerve. In addition, vitamin D receptor (VDR) gene expressions in pancreatic (VDR-P) and sciatic nerve (VDR-N) tissues were estimated and the homeostasis model assessment for insulin resistance index was calculated for each group. Results Data showed a significant reduction in nerve conduction velocity of the sciatic nerve, together with increased insulin resistance in diabetic rats that paralleled increased MDA and IL1β and decreased IL10. Administration of insulin alone, vitamin D alone, or both combined after induction of diabetes improved the nerve conduction velocity. This improvement was accompanied by significant enhancement of VDR-P and VDR-N gene expression, together with reduction in oxidative stress and inflammatory state. Conclusion The improvement of insulin sensitivity and neuroprotection with vitamin D supplementation in T2DM is related to restoration of VDR-P and VDR-N expression. Thus, vitamin D could be a novel approach to lower neuropathic risk in diabetes.

Print this article     Email this article
 Next article
 Previous article
 Table of Contents

 Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
 Citation Manager
 Access Statistics
 Reader Comments
 Email Alert *
 Add to My List *
 * Requires registration (Free)

 Article Access Statistics
    PDF Downloaded159    
    Comments [Add]    

Recommend this journal