Tinted sunscreens lead to a smaller amount of the product applied on the face

Decrypting the Potential of Nanotechnology-Based Approaches as Cutting-Edge for Management of Hyperpigmentation Disorder

The abundant synthesis and accretion of melanin inside skin can be caused by activation of melanogenic enzymes or increase in number of melanocytes. Melasma is defined as hyperpigmented bright or dark brown spots which are symmetrically distributed and have serrated and irregular borders. The three general categories of pigmentation pattern include centro facial pattern, malar pattern, and mandibular pattern. Exposure to UV rays, heat, use of cosmetics and photosensitizing drugs, female sex hormonal therapies, aberrant production of melanocyte stimulating hormone, and increasing aesthetic demands are factors which cause the development of melasma disease. This review gives a brief overview regarding the Fitzpatrick skin phototype classification system, life cycle of melanin, mechanism of action of anti-hyperpigmenting drugs, and existing pharmacotherapy strategies for the treatment of melasma. The objectives of this review are focused on role of cutting-edge nanotechnology-based strategies, such as lipid-based nanocarriers, i.e., lipid nanoparticles, microemulsions, nanoemulsions, liposomes, ethosomes, niosomes, transfersomes, aspasomes, invasomes penetration-enhancing vesicles; inorganic nanocarriers, i.e., gold nanoparticles and fullerenes; and polymer-based nanocarriers i.e., polymeric nanoparticles, polymerosomes, and polymeric micelles for the management of hyperpigmentation.

Update on Melasma-Part II: Treatment

Melasma is a prevalent chronic relapsing pigmentary disorder that affects photoexposed areas, especially in women of childbearing age. Although there is currently no curative treatment available for melasma, this manuscript critically reviews the knowledge regarding photoprotection, topical and oral therapies, and procedures such as peelings, laser, and microneedling that represent the main strategies for control and prevention of this disease. As the pathogenesis of melasma is not entirely understood, there are prospects for the development of new therapeutic strategies that might act on the pathways that promote sustained pigmentation rather than merely decreasing melanin synthesis and removing melanin from the epidermis.

Update on Melasma-Part I: Pathogenesis

Melasma is a multifactorial dyschromia that results from exposure to external factors (such as solar radiation) and hormonal factors (such as sex hormones and pregnancy), as well as skin inflammation (such as contact dermatitis and esthetic procedures), in genetically predisposed individuals. Beyond hyperfunctional melanocytes, skin with melasma exhibits a series of structural and functional alterations in the epidermis, basement membrane, and upper dermis that interact to elicit and sustain a focal hypermelanogenic phenotype. Evolution in the knowledge of the genetic basis of melasma and the cutaneous response to solar radiation, as well as the roles of endocrine factors, antioxidant system, endothelium proliferation, fibroblast senescence, mast cell degranulation, autophagy deficits of the melanocyte, and the paracrine regulation of melanogenesis, will lead to the development of new treatments and preventive strategies. This review presents current knowledge on these aspects of the pathogenesis of melasma and discusses the effects of specific treatments and future research on these issues.