Short- and Long-Term Effects of Vitamin D Treatment on Bacillus Calmette-Guerin-Induced Depressive-Like Behavior in Mice

Purpose: Depression is one of the most common psychological disorders. The nutritional etiology of the depression proposes that vitamin D may play a significant role in the pathogenesis of depression. Further, vitamin D deficiency has been found to aggravate depression in animals. Therefore, vitamin D treatment might be a potential therapeutic aid in depression management. This study aimed to explore the antidepressant effects of vitamin D in a Bacillus Calmette-Guerin (BCG)-induced depression model.

Methods: Thirty-six mice were randomly assigned to short-term and long-term experimental groups. In each group, mice were randomly subcategorized into three subgroups: 1. control (received vehicle), 2. BCG (received BCG [10 CFU/mouse]), and 3. BCG + vitamin D (received vitamin D [60.000 IU/kg] before BCG [10 CFU/mouse] inoculation). After completion of the two experimental periods (3 days for the short-term group and 2 weeks for the long-term group), the mice underwent three behavioral tests: locomotor activity, the forced swimming test (FST), and the tail suspension test (TST).

Results: Locomotor activity did not significantly differ among the subgroups in either the long-term or short-term groups. In the short-term group, the total immobility time on the FST was decreased in the vitamin D-treated group compared to the BCG group. However, in the TST, no significant difference was found between the vitamin D-treated group and the BCG group. In the long-term group, the immobility time on the FST was decreased in the vitamin D-treated group compared to the BCG group. Similarly, the total immobility time on the TST was also significantly lower in the vitamin D-treated mice than in the BCG-treated mice.

Conclusion: Vitamin D is useful in the management of depressive behavior. The potential role of vitamin D in the etiology of depression should be investigated in future work.