Skin Lightening reduces dark skin spots or uneven hyperpigmented areas of the skin caused by hyperpigmentary disorders such as melasma, café au lait spots, solar lentigo, etc. With the advancement in dermatological & cosmetology research backed by molecular sciences and the latest technologies, many modalities have been developed to achieve skin lightening. These include laser therapies such as Resurfx, minimally invasive dermatology procedures like dermabrasion, micro-needling, etc.

The most common and widely used approaches are oral SkinCeuticals and topical application of skin preparations that contain skin lightening agents like Hydroquinone, Kojic Acid, Alpha Arbutin, and Liquorice extract, Azelaic Acid, Lactic Acid, Glycolic acid, and many other specialized formulations. Hykozi BE-BRIGHT skin lightening treatment and Brightening Formula for Hyperpigmented Skin. Hykozi is a unique skin lightening treatment & Skin Brightening formula developed by dermatologists to relieve skin hyperpigmentation, melasma, post-inflammatory hyperpigmentation, and other hyperpigmentary conditions.

The process of production of melanin in the skin is known as melanogenesis. UV rays from the sun alter the DNA of Keratinocytes in the dermis, which activates the Melanocytes via a series of complex steps mediated by enzymes and cofactors. These melanosomes are then transported from Melanocytes to Keratinocytes, and then melanin is released to the epidermis. This imparts color to the skin. The function of melanin is to protect the skin from UV rays, which cause free radical oxidative damage to the DNA.

The key enzymes & mediators involved in melanogenesis are Tyrosinase, Phenylalanine hydroxylase (PAH), Tyrosinase hydroxylase isoenzyme 1 (TH-I), DOPA-oxidase, and Tyrosinase-related proteins (TRP-1,2)

1. Hydroquinone inhibits tyrosinase activity, and cellular metabolism affects both DNA and RNA syntheses and melanin.
   

2. Kojic Acid/Kojic acid tripeptides inhibit the catecholase activity of tyrosinase.

3. Arbutin/deoxyarbutin inhibits tyrosinase, tyrosine hydroXylase, DOPA-oxidase, and melanin production.

4. α-Hydroxy acid-like Glycolic acid and lactic acid inhibit Tyrosinase activity & melanin formation.

5. Licorice extract Glabiridin Glabrene and isoliquiritigenin inhibit mono- and diphenolase tyrosinase activities.

6. Azelaic acid limits melanin creation by inhibiting tyrosinase.

7. Aloesin Inhibits tyrosinase, tyrosine hydroxylase, and DOPA oxidase together with arbutin Resveratrol, reducing MITF and tyrosinase promoter activities.

8. Soybean inhibits protease-activated receptor 2 cleavage, affects cytoskeletal and cell surface organization, and reduces keratinocyte phagocytosis.

9. Niacinamide inhibits the catalytic activity of tyrosinase on melanogenesis and inhibits melanosome transfer.

10. Retinoic acid inhibits tyrosinase/TRP-1 protein expression and melanin synthesis.

11. Vitamin C (magnesium ascorbyl phosphate) Suppresses Tyrosinase induced melanin formation in melanocytes.

12. Octadecenedioic acid reduces tyrosinase mRNA and protein expression, inhibiting melanogenesis.

13. Serine protease inhibitors inhibit Melanosome transfer.

14. Phyllanthus Emblica (fruit) extract has antioxidant activity and chelating properties and inhibits MMP-1 and MMP-3.

15. Glutathione, directly and indirectly, inhibits tyrosinase enzyme and favors pheomelanin over eumelanin production.

16. Several other ingredients like Evening prime rose oil, Gold, rose seed oil, Lemongrass oil, Pumpkin seed oil, Orange peel oil, Vit E, Salicylic acid, Squalene, Shea butter, Lecithin, Cocoa butter, Aloe vera, Mulberry extract, Bio white, Raguage, Pentavitine along with many others help in the process of skin lightening by different mechanisms.

17. Not all skin-lightening agents are included in this article.

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