Method Development of Skin Brightening Product Efficacy Testing For Gene Expression Assay Using RT-PCR: a Literature Review PT. Skinproof Derma Lab Asia

Abstract

Skin brightening products efficacy testing are usually done by colorimetry or spectrophotometry method. In this project, the method for gene expression analysis using RT-PCR for testing the efficacy of skin brightening products is analyzed and developed. A literature review is used to analyze the ingredients used in skin brightening products, select genes for RT-PCR, and develop a protocol for gene expression assay. The ingredients analysis shows that various skin brightening ingredients such as ascorbic acid, hydroquinone, niacinamide, kojic acid, and 𝛼-bisabolol show an inhibitory activity towards the skin pigmentation, such as decreasing the melanin production, reducing transfer speed of melanin, and inhibiting the activation of tyrosinase and TRP-1/TRP-2. With that, the genes that were selected include tyrosinase and TRP-1/TRP-2 as they play an important role in the melanogenesis pathway. The method that was developed for the gene expression assay in the protocol includes the MTT assay, tyrosinase activity assay, and RT-PCR followed by statistical analysis. The Human Epidermal Melanocytes (HEM) cells will be treated with skin brightening products, with arbutin as the L-DOPA inhibitor, as the substrate for the synthesis of skin pigmentation, and untreated cells as the negative control. Further observations and other references from past or recent studies may also be analyzed to optimize the protocol and ensure the success of the testing.