Antimelanogenic and Antimelanoma Activity of Isorhamnetin Isolated from Acalypha indica Linn

Abstract

Acalypha indica is one of the traditional medicinal plants that is used for treating various skin disorders but very minimal work has been done on antimelanogenic and antimelanoma activity Among the different extracts obtained from Acalypha indica the ethyl acetate extract has good antioxidant activity with an IC50 value of 42 point 75 and 14 point 55 microgram per milli liter for the DPPH and ABTS assays respectively The ethyl acetate extract showed a good cytotoxic effect on the A375 melanoma Cell Line with an IC50 value of 56 point 6 microgram per milli liter The inhibitory effect of ethyl acetate extract on melanin production was demonstrated in vivo using zebrafish embryos The melanin content of the eye and body of the treated zebrafishes were quantified visually using stereo microscopy and Image J software The HRLCMS analysis of the ethyl acetate fraction showed the presence of 41 different compounds and hence fractionated further to obtain pure compounds Crystals obtained from the fractionated extract were analyzed by mass spectra FTIR CNMR and HNMR and revealed the compound to be isorhamnetin Molecular docking analysis of the compound with tyrosinase related protein 1 TRP1 PDB ID 5M8M showed good binding minus5 point 64 Kcal per mol thereby demonstrating the antimelanogenic potential of the compound The compound showed good antimelanogenic activity in the treated cells as evidenced by the reduction in cellular tyrosinase activity and melanin concentration The DNA fragmentation analysis Acridine orange and Ethidium bromide staining revealed the antimelanoma function of the compound in the A375 melanoma cells Further cell cycle analysis showed arrest at sub G0 and G1 phase with the depletion of cells in S and G2M phase The analysis of the pro apoptotic genes Caspase 3 Caspase 9 and BAX and tumor suppressor p53 gene confirmed the antimelanoma activity Hence the isorhamnetin isolated from the Acalypha indica showed antimelanogenic and antimelanoma activity both in vitro and in vivo Hence this study suggests i