Vitamin D for psoriasis

The lowest epidermis cells are round undifferentiated keratinocytes of the basal layer, placed directly on the underlying dermis. In the course of their continuing proliferation new cells are formed, which form the upper layers of the epidermis. After keratinocytes “leave” basal layer, there begins the process of differentiation (specialization of cells for performance of specific functions), also known as keratinization, and then with actinic transformation of keratinocytes into corneocytes. Thus, new cells from the basal layer replace the upper layer of skin cells, which is gradually exfoliated.

Together with various coregulators 1,25-dihydroxyvitamin-D3 and its receptor VDR regulates the above mechanisms of maintenance of cellular skin composition. In general, Vitamin D inhibits the activity of genes responsible for the proliferation of keratinocytes and induces the activity of genes responsible for differentiation of keratinocytes. Complementing the effects of steroid hormones, vitamin D regulates the biochemical processes that provide calcium entry into the cell, which is essential for cell differentiation. Proliferaion and differentiation of the epidermis is necessary for normal cell growth, wound healing and maintenance of skin barri er function. Since uncontrolled reproduction of cells with defined mutations can lead to malignancies, vitamin D may protect against certain types of cancer pathology. This vitamin plays a very significant role in body psoriasis treatment.

Vitamin D benefits

Depending on the dose UV radiation can lead to DNA damage, inflammatory reactions, apoptosis (programmed death) of skin cells, skin aging and malignant neoplasms. During studies in vitro (in cell culture) and in mice when applied topically 1,25-dihydroxyvitamin-D3 before or immediately after exposure, it was found that vitamin D has a photo-protective effect.
1,25-dihydroxyvitamin-D3 regulates the activity of cathelicidin – antimicrobial protein, which is a mediator of the innate immune system of the skin and promotes healing of wounds and tissue restoration. One of the studies in volunteers showed that cathelicidin activity occurs in the early stages of normal wound healing. Other studies found that cathelicidin modulates inflammation in the skin, induces angiogenesis and improves re-epithelialization (the recovery process of the epidermal barrier, which protects the germ cells from the environment). The active form of vitamin D and its analogues activates cathelicidin expression in cultured keratinocytes.
In the treatment for psoriasis preparations of vitamin D are often used. They help to reduce the rate of reproduction of skin cells since they cause their differentiation. As a result of this abnormally active process of changing the epidermis, which is characteristic of this disease, significantly slows down. Easily permeating through cell membranes, drugs bind to the receptors of keratinocytes, fibroblasts and certain types of leukocytes. Forms of medications may be different – creams, ointments, lotions. The latter are applied to the nail plate and the skin of the head, but the hair presence reduces the efficiency of this method of therapy.