calcitriol and Vitiligo

Vitiligo is a common autoimmune skin disease caused by autoreactive CD8+ T cells. The diverse effects of 1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃] on immune cell metabolism and proliferation have made it an interesting candidate as a supporting therapeutic option in various autoimmune diseases. This study aimed to elucidate the immunomodulatory effects of 1,25(OH)₂D₃ in vitiligo. Cross-sectional relationships between serum 1,25(OH)₂D₃ levels and disease characteristics were investigated in 327 patients with vitiligo. The immunomodulatory and therapeutic effects of 1,25(OH)₂D₃ were then investigated in vivo and in vitro, respectively. We found that 1,25(OH)₂D₃ deficiency was associated with hyperactivity of CD8+ T cells in the vitiligo cohort. In addition, 1,25(OH)₂D₃ suppressed glycolysis by activating the AMP-activated protein kinase (AMPK) signaling pathway, thereby inhibiting the proliferation, cytotoxicity and aberrant activation of CD8+ T cells. Finally, the in vivo administration of 1,25(OH)₂D₃ to melanocyte-associated vitiligo (MAV) mice reduced the infiltration and function of CD8+ T cells and promoted repigmentation. In conclusion, 1,25(OH)₂D₃ may serve as an essential biomarker of the progression and severity of vitiligo. The modulation of autoreactive CD8+ T cell function and glycolysis by 1,25(OH)₂D₃ may be a novel approach for treating vitiligo.

Topics: Animals; Calcitriol; CD8-Positive T-Lymphocytes; Humans; Mice; Vitiligo

High interleukin (IL)-17 contributes to vitiligo pathogenesis. Vitamin D has been assessed in vitiligo, with no reports targeting its relation to IL-17.. To evaluate a possible regulatory effect of vitamin D on IL-17 and their relation to disease activity in vitiligo.. This study included 30 vitiligo patients and 40 controls evaluated for IL-17 and vitamin D serum levels by ELISA technique.. IL-17 was significantly higher (p = 0.001) whereas vitamin D was found to be lower among the patients (p < 0.001). Multivariable regression was performed to evaluate the relationship between IL-17 and vitamin D levels with the demographic data on the patients, revealing a nonsignificant relationship (p > 0.05). A significant positive correlation was noted between vitamin D levels and disease duration.. Vitamin D represents a potential player in the pathogenesis of vitiligo. Its possible regulatory relation to IL-17, together with its weight as a screening tool in vitiligo, needs further evaluation.

Topics: Adolescent; Adult; Case-Control Studies; Cross-Sectional Studies; Female; Humans; Interleukin-17; Male; Vitamin D; Vitiligo; Young Adult