Melatonin - A Cutaneous Perspective

Tapan Dhali,Priyanka Hemrajani,Mona Sharma

doi:10.3126/njdvl.v19i2.39452

Abstract

Melatonin (MLT) is an endogenous hormone secreted from the pineal gland, located deep in the brain in the epithalamus associated with numerous biological activities. The primary function of melatonin is to regulate sleep-wake cycles. However, research over the last few years has enlightened a range of functions associated with this molecule, including anti-inflammatory, direct and indirect antioxidant activity, regenerative tissue benefits, and preservation of mitochondrial function. Melatonin’s anti-inflammatory and antioxidant support, coupled with its mitochondrial modulation, makes it a vital molecule to use for skin health homeostasis. The cutaneous melatoninergic system’s widespread expression and pleiotropic activity provides for a high level of cell-specific selectivity. Several skin cells, including normal and malignant keratinocytes, melanocytes, fibroblasts and hair follicles, express melatonin receptors. Melatonin also has receptor-independent effects that protect against oxidative stress and can reduce ultraviolet radiation-induced damage. Several functions of melatonin in the skin have been experimentally implicated such as hair growth cycling, fur pigmentation, melanoma control, suppression of ultraviolet-induced damage to the skin cell. Melatonin may play a role in treating several dermatoses e.g., atopic eczema, psoriasis, melasma, ulcer healing, and malignant melanoma. There is a plethora of functional melatonin properties, which still await to be fully appreciated by dermatologists. The current review emphasizes few of the established uses and few emerging potentialities that render melatonin a promising candidate for managing several diseases.

Highlights

Melatonin, an evolutionarily ancient derivative of serotonin with hormonal properties, is the primary neuroendocrine secretory product of the pineal gland
Research has proved that melatonin inhibits melanoma growth and melanin dispersion by reducing the levels of cyclic adenosine monophosphate and α‐melanocyte‐ stimulating hormone (MSH) apart from its antioxidant action against UV‐induced free radicals.[11]
This activity depends on the level of expression of MT1 and MT2 receptors and melatonin-binding quinone reductase NQO2 in both skin cell lines as well as melanoma cell lines.[36,37]

Summary

Introduction

An evolutionarily ancient derivative of serotonin with hormonal properties, is the primary neuroendocrine secretory product of the pineal gland. Melatonin and its metabolites have been shown to inhibit cultured human melanoma cell growth,[28,29,30,31] and attenuation of benzo(a)pyrene-induced cutaneous sarcomas, squamous cell carcinomas, and papilloma in mice models.[32,33,34] Gadheri et al found that patients with basal cell and squamous cell carcinomas had lower urinary indicators of systemic melatonin production than controls.[35] Research has proved that melatonin inhibits melanoma growth and melanin dispersion by reducing the levels of cyclic adenosine monophosphate (cAMP) and α‐melanocyte‐ stimulating hormone (MSH) apart from its antioxidant action against UV‐induced free radicals.[11] This activity depends on the level of expression of MT1 and MT2 receptors and melatonin-binding quinone reductase NQO2 in both skin cell lines as well as melanoma cell lines.[36,37] Melatonin and its precursor N-acetylserotonin bind to several regulatory proteins including quinone reductase 2.38-39 Quinone reductase 2, protects cells against oxidative stress in dimethylbenz(a)anthraceneinduced skin cancer and is required for tumour necrosis factor-α-induced apoptosis in keratinocytes.[40,41]. Like other immunomodulatory agents, may be used as an effective adjuvant besides vaccination to boost the vaccine's effectiveness in patients with both compromised and healthy systemic and cutaneous immune systems.[67, 68]

Conclusion

Findings

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