The effects of in vitro vitamin D treatment on glycolytic reprogramming of bone marrow-derived dendritic cells from Ldlr knock-out mouse.

Dendritic cells (DCs) undergo glycolytic reprogramming, a metabolic conversion process essential for their activation. Vitamin D has been reported to affect the function of DCs, but studies in metabolic diseases are insufficient. This study investigates the effects of in vitro 1,25-dihydroxyvitamin D3 (1,25(OH)D) treatment on glycolytic reprogramming of bone marrow-derived dendritic cells (BMDCs) from control, obese, and atherosclerosis mice. Six-week-old male C57BL/6J mice were fed a control diet (CON) or a Western diet (WD), and B6.129S7-Ldlr/J mice were fed a Western diet (LDLR) for 16 weeks. BMDCs were cultured in a medium containing 1,25(OH)D (10 nM) for 7 days and stimulated with lipopolysaccharide (LPS, 50 ng/mL) for 24 h. In mature BMDCs, 1,25(OH)D treatment decreased basal and compensatory glycolytic proton efflux rates (glycoPER), the expression of surface markers related to immune function of DCs (MHC class II, CD80, and CD86), and IL-12p70 production. In addition, mTORC1 activation and nitric oxide (NO) production were suppressed by 1,25(OH)D treatment in mature BMDCs. The effect of 1,25(OH)D treatment on IL-12p70 production and mTORC1 activity in the LDLR group was greater than in the CON group. These findings suggest that vitamin D can affect the metabolic environment of BMDCs by regulating glycolytic reprogramming as well as by inducing tolerogenic phenotypes of DCs.