Restorative Action of Vitamin D3 on Motor Dysfunction Through Enhancement of Neurotrophins and Antioxidant Expression in the Striatum

A number of studies has explored a positive correlation between low levels of serum Vitamin D3 (VD; cholecalciferol) and development of neurodegenerative diseases including Huntington's disease (HD). In the present study, the prophylactic effect of VD on motor dysfunction was studied in an experimental model of HD. An HD-like syndrome was induced in male C57BL/6 mice through an intraperitoneal injection (i.p) of 3-NP for 3 consecutive doses at 12 h interval of time as described previously (Amende et al. 2005). This study investigated thein-vivotherapeutic potential of VD (500 IU/kg/day) supplementation on movement, motor coordination, motor activity and biochemical changes in this HD model. Mice were divided into four groups: Group I: Control (saline); Group II: 3-NP induced HD (HD); Group III: Vitamin D3 (VD) and Group IV: 3-NP induced + post Vitamin D3 injection (HD + VD). All groups of mice were tested for locomotion, gait analysis and rotarod performances over a span of 30-days. VD administration rescued locomotor dysfunction and neuromuscular impairment in HD mice with no change in gait dynamics. In addition, administration of VD to 3-NP treated mice led to a significant enhancement in the expression of key neurotrophic factors including brain-derived neurotrophic factor (BDNF) and nerve-growth factor (NGF), the Vitamin D receptor (VDR), and antioxidant markers (catalases [Cat] and glutathione peroxidase [GpX4]) in the striatum, suggesting a detoxification effect of VD. Altogether, our results show that VD supplementation induces survival signals, diminishes oxidative stress, and reduces movement and motor dysfunction in HD.