Effects Of Fructus Ligustri Lucidi And Its Monomer On The Adhesion, Migration And Actin Of Human Epidermal Melanocyte

ObjectiveTo stuudy the effect of fructus ligustri lucidi and its monomer oleanolic acid, quercetin and tyrosol on the adhesion, migration and cellular actin of cultured human melanocyte, in order to further study of the mechanism of fructus ligustri lucidi in treating vitiligo.MethodsTo cultured human epidermal melanocytes in vitro, treated melanocyte with different concentrations of fructus ligustri lucidi and its monomer oleanolic acid, quercetin and tyrosol, the cell proliferation was detected by XTT assay, the cell adhesion rate was determined by FN-coated culture plates, the migration of melanocyte were detected by the method of transwell assay.We observed the structure and distribution of cellular actin cytoskeleton with confocal laser microscopy, and do a semi-quantitative analysis of cellular fluorescence intensity.Result1.At the range of 0.0375～0.3mg/ml of fructus ligustri lucidi, showed an increasing tendency of the adhesion of melanocyte with the corresponding increase of drug concentration compared with the control group(melanocyte without drugs treatment).When the concentration of fructus ligustri lucidi was at 0.6mg/ml,the adhesion rate of melanocytes began to decline. When the concentration of quercetin was at 40μmol/L, it could improve the adhesion of melanocytes, there was a significant difference compared with the control group (P<0.05). At the range of 0.5～2 mmol/L of tyrosol, the adhesion of melanocytes could be improved,and when the concentration of tyrosol was at 2 mmol/L, the effect was the strongest (P<0.01). There was no significant difference between the test concentrations of oleanolic acid and the control group.2. According to the results of proliferation of melanocyte, we choice the working concentrations of transwell assay were the highest concentration with no cytotoxicity and without obvious stimulation of cell proliferation at 24h.Transwell assay revealed a promoting effect of both fructus ligustri lucidi and tyrosol on melanocyte migration(P<0.01),when the working concentrations of fructus ligustri lucidi and tyrosol was determined at 0.15 mg/ml and 2 mmol/L respectively;there was a significant difference of the count of melanocyte that through microfiltration membrane between the concentration of oleanolic acid at 12μmol/L and the control. (P<0.05);while the working concentration of quercetin at 40μmol/L had little effect on the migration of melanocyte.3.More stress fibre fasciculus were formed by F-actin were found in the human epidermal melanocyte cell which was treated with Fructus ligustri lucidi(0.15 mg/ml), oleanolic acid (12μmol/L), quercetin (40μmol/L) and tyrosol (2 mmol/L) compared with the control group(melanocyte without drugs treatment). The stress fibre fasciculus were distributed inside the cell membrane and around the nucleus. Intracellular fluorescence intensity in this four groups was higher than the control group.Conclusion1. Fructus ligustri lucidi has a significant stimulatory effect on the adhesion and migration of human melanocyte.2. Tyrosol has a significant stimulatory effect on the adhesion and migration of human melanocyte; quercetin can promote the adhesion of human melanocyte,but has no significant effect of the migration; oleanolic acid can induce the migration of melanocyte,but has little effect on melanocyte adhesion. Oleanolic acid, quercetin and tyrosol may be the active components of Fructus ligustri lucidi which have confirmative effect on adhesion and/or migration of human epidermal melanocyte.3. Fructus ligustri lucidi and its monomer oleanolic acid, quercetin and tyrosol may indirectly stimulate the adhesion and migration of human melanocyte by promoting the actin cytoskeleton congregation in melanocyte in vitro.