The Relationship Between Vitiligo and the Immune Function of the Body

The endocrine system is an information transmission system composed of endocrine glands and endocrine cells in certain organs, which are closely related to the nervous and immune systems and coordinate with each other to regulate the physiological activities of the body and maintain the relative stability of the internal environment. Hormones, which are highly effective living active substances secreted by endocrine glands or endocrine cells, function through tissue fluid and blood transmission. Experimental studies have shown that: melanocyte-stimulating hormone, Adrenocorticotropic hormone (ACTH) and sex hormones can promote melanin anabolism. And glucocorticoids, adrenaline and norepinephrine, thyroxine and melatonin can inhibit the metabolic synthesis of melanin, these show that vitiligo and endocrine relationship is very close.

1. Melanocyte-stimulating Hormone:

Some studies have shown that human melanocyte-stimulating hormone could be secreted by pituitary gland. And there are two types of melanocyte-stimulating hormone: α melanocyte-stimulating hormone has no interspecific differences and has little or no effect on melanocytes; β melanocyte-estrogen has interspecific differences and is closely related to pigmentation disorders.

2. Corticosteroids:

Secreted by the adrenal cortex, synthetic corticosteroids such as prednisone, dexamethasone and hydrocortisone are commonly used, and their effects on melanin metabolism are mainly related to melanocyte stimulating hormone. Under normal conditions, melanocyte-stimulating hormone and glucocorticoid levels in the blood are relatively balanced, and once they are out of balance, the skin color is affected.

3. Adrenocorticotropic hormone (ACTH):

Secreted by the anterior pituitary gland, many patients clinically experience deepening of existing pigmented nevi and production of new pigmented nevi after systematic use of ACTH, and deepening of skin color after local application, which may be related to ACTH containing melanocyte stimulating hormone.

4. Epinephrine and Norepinephrine:

Animal experiments have shown that trace amounts of epinephrine or norepinephrine can inhibit the effect of melanin-stimulating hormone on isolated frog skin melanocytes.

5. Thyroxine:

Secreted by the thyroid gland, there are two types of tetraiodothyronine and triiodothyronine, which are both iodides of tyrosine.

6. Sex hormones:

Including estrogen and progesterone, can activate tyrosinase inhibited by sulfhydryl groups, promote melanin synthesis by melanocytes and make skin color deepen.

7. Melatonin:

Acts by binding to specific receptors on melanocyte membranes, causing skin discoloration.

8. Prostaglandins:

Prostaglandin E2 stimulates melanocyte proliferation and promotes melanin synthesis.