Melasma: How hormones can modulate skin pigmentation

Abstract

Melasma is a relatively common acquired disease, characterized by a pattern of emarginated, symmetric, light-to-dark brown facial hyperpigmentation. Some areas of the skin are more exposed to the sun, such as the cheeks, forehead, upper lip, nose, and chin and sometimes, neck as well.According to their distribution, melasma is classified into three types: centrofacial, malar, and mandibular patterns. 1 Histologically, melasma is characterized by excessive melanin deposition in the epidermis (epidermal type, 70%), dermal macrophages (dermal type, 10%), or both (mixed type, 20%). Melasma considerably affects patients' quality of life-with considerable emphasis on its therapeutic difficulty. Melasma is usually clinically diagnosed; however, Wood's lamp examination, confocal microscopy, and histology are helpful tools for distinguishing epidermal from dermal melasma. 2 Women of Hispanic and Asian origin are more commonly affected by melasma. 3 Melasma affects most patients in the 3rd or the 4th decade of life; the onset of the disease is found to be earlier in light skin types, whereas dark skin types are usually associated with a late onset of melasma. 4 Although the prevalence of melasma among various ethnic groups and skin phototypes is different, the preferential development of melasma during women's reproductive age and the association of this disease with oral contraceptives suggest that female sex hormones accelerate the development and aggravation of melasma-even if the impact of female hormones has been recently minimized. 4 During pregnancy, in particular in the third trimester, the levels of placental, ovarian, and pituitary hormones, which are a stimulus for melanogenesis, are increased. According to different observations, 5 melasma in pregnancy is more likely to be associated with circulating female hormones than melanocyte-stimulating hormone (MSH) peptides. Through the induction of synthesis of melanogenic enzymes such as tyrosinase and tyrosinase-related proteins 1 and 2, estrogens stimulate melanogenesis in cultured human melanocytes.The increase in progesterone levels that occurs during pregnancy and the increase in estrogen production that occurs from the eighth to the thirtieth week of pregnancy reflects, indeed, the typical pattern of progression of hyperpigmentation. Epidemiological data showed that melasma occurs in 14.5%-56% of pregnant women and in 11.3%-46% of individuals who take oral contraceptives in different countries. 6 A study performed on 324 women with melasma in nine different countries worldwide revealed that melasma occurs in only 20% of cases in pregnancy and almost 10% start after menopause.In addition, the study demonstrated that cessation of contraceptive pills weakly affects the development of the disease. 7 Melasma has been considered as a consequence of contraceptives with synthetic progestin levonorgestrel, 8 even if the role of progesterone in skin pigmentation has to be established. It has been found out that progesterone is involved in the pathogenesis of melasma by s...

Role of Amine Neurotransmitters and Their Receptors in Skin Pigmentation: Therapeutic Implication

“…This process can be affected by a variety of factors. For example, pregnancy, Addison’s disease, and sun exposure can all make the skin darker [ 11 , 12 , 13 , 14 ]. Too little melanin in the body brightens skin.…”

“…Extensive hyperpigmentation can be caused by hormonal changes, internal diseases, drugs, and exposure to heavy metals [ 19 , 84 ]. Hormonal changes can increase melasma in pregnancy or the use of hormonal contraceptives and hyperpigmentation in Addison’s disease [ 11 , 85 , 86 ]. A liver disease called primary biliary cholangitis (previously called primary biliary cirrhosis) can also increase melanin production [ 87 ].…”

Melasma

“…3,7 • Hormonal influences -oestrogen and progesterone may be implicated in the Melasma development of melasma, particularly given the increased prevalence of melasma during pregnancy, with the use of oral contraceptive agents containing oestrogen and progesterone, menopausal hormone therapy, intrauterine devices and implants. 2,8,9 The activities of oestrogens and progesterones are mediated by specific oestrogen and progesterone receptors expressed in human skin. These have been implicated in a quarter of affected women.…”

Chalcones in Dermatology

“…Melasma is a multifactorial skin disease indicated by the presence of symmetrical hyperpigmented area in a certain part of the face including centrofacial, malar, and mandibular parts. This disease is affected by UV, visible, and infrared exposure, by inducing reactive oxygen species and promoting melanogenesis [44], hormonal conditions [45], and genetics [46]. Chalcone derivatives are extensively used in medical therapy as photoprotective described in Sections 2.1 and 2.2, and hypopigmenting agents.…”