Shedding Light on Siring of Darker Pigment Melanin

The skin is presumably the largest and one of the most versatile body organs. By providing a physical barrier, it protects our bodies from environmental assaults.

Melanin is a natural pigment produced by specialized skin cells called melanocytes that shields our body from the detrimental effects of ultraviolet (UV) radiation. UV radiation is responsible for DNA damage, and genetic mutations, and can also lead to the onset of skin cancer.

Skin Cancer - Types, Causes, Symptoms, Diagnosis, Treatment & Prevention
Skin cancer is an abnormal growth of skin cells. It can develop due to a continuous exposure to sun over the years.

‘Melanin production occurs by regulating the uptake of large amounts of fluids and membranes—and recycling old cell components.’

Tweet it Now

NF-E2-related factor 3 or ‘Nrf3,’ a known transcription factor, or protein involved in the process of converting DNA into RNA, is abundantly found in the basal layer of the epidermis. However, its precise role in melanin production remains largely elusive.

Researchers in Japan have recently been able to discover the Nrf3-mediated mechanism of melanogenesis using in vitro experimentation.

Novel Insights on the Mechanism of Melanin Formation

The research team showed that Nrf3 coordinates melanin production by regulating two key processes: macropinocytosis—engulfment and uptake of large amounts of fluids and membranes—and autophagy—recycling of old, damaged, abnormal cell components through controlled cellular breakdown.

To this end, the researchers generated mouse malignant melanocyte (melanoma) B16F10 cells overexpressing Nrf3 or depleted the gene in normal human melanocyte (NHEM) cells and conducted a series of well-controlled experiments. This study is published in the journal Cell Reports.

Now a �Natural Sunscreen� With Melanin Like Cells Can Protect You from UV Rays
Melanin like nanoparticles have been developed which offer good UV protection and show promise as a good ‘natural’ sunscreen.

Moreover, they revealed that Nrf3 also induces the gene expression of Cln3, an autophagosome-related factor, for macropinocytosis uptake of melanin precursors.

In addition, they identified two autophagy-related genes targeted by Nrf3, i.e., Ulk2 and Gabarapl2, which contribute to the uptake of melanin precursors and the formation of melanosomes—specialized organelles responsible for the synthesis, storage, and transport of melanin.

Scientists Have Found Possible Cure for Gray Hair and Vitiligo
Loss of skin and hair color can be corrected by reversing oxidative stress with PC-KUS, a pseudocatalase, according to a team of European researchers.

Researchers also found that Nrf3 triggers the recycling of skin tissues by facilitating the autolysosomal degradation of melanosomes.

Furthermore, the team showed that αMSH—a hormone that stimulates melanocytes—causes Nrf3 activation and the subsequent formation of melanin, whereas nelfinavir, an HIV-1 protease inhibitor, inhibits Nrf3-mediated melanin formation.

Tips to Protect Your Children from Sun�s Ultraviolet Radiation
Wearing the right clothing, applying sunscreen appropriately, and seeking shade during peak hours of UV radiation, can greatly reduce the risk of skin cancer.

These findings demonstrated the physiological role of Nrf3 in the melanogenesis cascade, via the regulation of cellular membrane dynamics and the core melanogenic gene circuit, as well as the therapeutic potential of nelfinavir in skin hyperpigmentation conditions.

They are hopeful that their novel findings will be of interest not only to other scientists but also to cosmetic and pharmaceutical companies engaged in pigmentation research.

Melanin functions as a natural sunscreen but its excessive production causes melasma (hyperpigmentation), age spots, and freckles. Although further studies seem warranted, the study does seem to establish a likely association between melanin overproduction and skin cancer.

Source-Eurekalert