The Role of VD/VDR Signaling Pathway in Autoimmune Skin Diseases.

BACKGROUND: Immune-related cutaneous diseases are a series of disorders, such as alopecia areata, psoriasis, atopic dermatitis, systemic lupus erythematosus and autoimmune bullous dermatoses. Vitamin D is a fat-soluble vitamin, which is known for its classical pleiotropic effect. Recent studies have found that vitamin D, after catalyzed into its biologically active form [1,25(OH) 2D], correlated with its receptor, vitamin D receptor, plays a vital role in multiple pathophysiological processes, including immune-related dermatoses. This review mainly summarizes evidence on the role of vitamin D/vitamin D receptor in immune-related cutaneous diseases and the potential therapeutic targets for skin disorders. METHODS: We have carried out a comprehensive literature search in PubMed and Google Scholar databases using keywords like "vitamin D", "vitamin D receptor", "immune", "psoriasis", "atopic dermatitis", "skin", "systemic lupus erythematosus", "alopecia areata" and "autoimmune bullous dermatoses". Only articles related to the topic were included in this review. Conference, patent, graduation thesis and articles without available full text were excluded. RESULTS: Vitamin D/vitamin D receptor is critical for skin in regulating the proliferation and differentiation of keratinocytes, keeping the integrity of the skin barrier as well as maintaining the homeostasis of the "skin's immune system". Vitamin D deficiency/vitamin D receptor mutations are potential risk factors for some immune-related cutaneous diseases. CONCLUSION: Vitamin D is a pleiotropic hormone, which is important in the homeostasis of human body. Many studies have revealed vitamin D deficiency in several skin diseases. Thus, vitamin D supplementation may be a useful therapeutic option for immune-related skin diseases.