[Immunomodulatory effects of vitamin D3 and bisphosphonates in nutritional osteoporosis in rats].

The aim of this study was to determine the effectiveness of separate and combined administration of vitamin D3 and different forms of bisphosphonate (disodium salt of methylenbisphosphonic acid dihydrate and alendronate) on the function of immune cells in rats with nutritional osteoporosis. It was shown that D-hypovitaminosis leads to reduced 25OHD3, which is a biomarker for vitamin D3 and disturbances of metabolic processes in bone tissue that correlated with osteoporosis manifestation. Immunologic disorders related to nutritional osteoporosis were accompanied by the decrease in phagocytic activity of granulocytes and impaired ability to produce bactericidal oxidants. Inhibition of B-cell immunity also occurred in patholgy. Thus, the present study revealed more pronounced immunomodulatory effects of vitamin D3 on phagocytic immunity, whereas bisphosphonates were effective in improving the humoral immune protection.