Study On The Water Extract Of Polygonum Multiflorum Affecting Melanin Biosynthesis In Murine Melanoma Cells Of Mice

With the development of our society, there is a growing pursuit of our own health and good looks. To have black hair is the dream of many people, but the appearance of white hair is one of the most common reasons that often make the patients annoyed. According to literature, traditional Chinese medicine Polygonum multiflorum thumb has the function of hair blacking and life prolonging. Melanin producted from melanocytes in the dermal papilla and the process is mediated by a variety of biosynthetic enzymes. Tyrosinase is an important enzyme which can oxidize tyr to dopa-tyrosine, further oxidize to DOPA quinone, and then polymerized to melanin.In this thesis, B16F1 murine melanin cells are cultured with various concentrations of Polygonum multiflorum water extract, 0mg/ml, 0.1mg/ml, 0.5mg/ml, 1mg/ml respectively. MTT is used to study the proliferation of cells, the tyrosinase activity is measured by enzymological method of L-dopa reaction in vitro; the synthesis of melanin is measured by NaOH-assay; and the method of RT-PCR is used to detect the expression of tyrosinase gene, tyrosinase-related protein -1 (TRP-l)gene, tyrosinase-related protein -2 (TRP-2) gene and MITF gene. Western blot is used to detect the protein expression. of four kinds of above-mentioned gene. The study showed that water extract of Polygonum multiflorum Thumb makes B16F1 melanin cells to activate the tyrosinase activity and increase melanin synthesis, and to promote cell proliferation dose-dependently. Polygonum multiflorum water extract can increase the four melanogenesis-related genes and their protein expression above-mentioned. Moreover, the results indicated that in a certain concentration range of 0 mg/ml to 1mg/ml, with the concentration increased, cell viability, tyrosinase activity and gene expression, protein expression increase in a dose-dependent manner. Taken together, we found that one mechanism for the water extract of Polygonum multiflorum thumb to promote melanogenesis may be due to its ability to promote the level of gene transcription and translation in melanogenesis-related genes.This thesis tries to extract active ingredients from Polygonum multiflorum thumb, and validates its blacking hair mechanism from the molecular level of cells, which provides a theoretical basis for further study in the melanogenesis-generating function and mechanism of Polygonum multiflorum thumb. At the same time, it provides strong evidence for evaluating modernization of traditional Chinese medicine.