Pharmacodynamic evaluation and mechanism of methoxyflavone to promote melanin production in zebrafish / 中草药

ABSTRACT

Objective: Based on the Chinese herbal property, the pharmacodynamic evaluation and mechanism discussion of active components were carried out through screening the active components of Chinese patent medicine in the clinical medical insurance catalog. Methods: The most frequently used main herbs were screened through the collection of anti-vitiligo Chinese patent medicine prescriptions, drug properties and material basis. The main compound types were acquired through TCMSP and TCMIP databases. The drug properties were analyzed by admetSAR method to obtain key compounds. The pharmacodynamics were observed by measuring the morphology and melanin content of adult zebrafish and larvae. The safety evaluation was indicated by the survival rate of larvae. RT-PCR was used to reveal the mechanism of the compounds at the transcriptional level. The binding ability of compounds to protein crystal structure was predicted by molecular docking. Results: The most frequently used main herbs were Carthamus tinctorius, Lithospermum erythrorhizon, Tribulus terrestris, Gentianae Radix et Rhizoma., Psoraleae Fructus, and Vernonia anthelmintica. The main compound types through TCMSP and TCMIP database were flavonoids with a total of 81. Based on the druggability and stability, the methoxyflavones kaempferide and isorhamnetin were screened out. Kaempferide (32 μmol/L), isorhamnetin (32 μmol/L) and methoxsalen (25 μmol/L) could promote the regeneration of melanin in zebrafish. Based on the zebrafish embryo model, kaempferide, isorhamnetin and methoxsalen all could accelerate melanogenesis in larvas, and the survival rates of larvas were more than 90% under effective concentration. RT-PCR showed that kaempferide and isorhamnetin upregulated the mRNA levels of MC1R and MITF genes related to melanogenesis. The results of molecular docking between the structures of proteins (MITF, TYR, TYRP1) and kaempferide, isorhamnetin, methoxsalen showed that the binding score of kaempferide or isorhamnetin was higher than that of methoxsalen. Conclusion: Kaempferide and isorhamnetin, the active ingredients in the clinical anti-vitiligo traditional Chinese medicine prescriptions, can promote the melanogenesis in zebrafish by up-regulating the MC1R/MITF signal pathway.