Research Article
MAPK and PI3K/Akt Signalling Pathways Potentially Modulate the Enhancing Effect of Black Tea Extracts on Endo180 Expression and Collagen Internalisation
Figure 5
Effects of mitogen-activated protein kinase (MAPK) or phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) inhibitors on black tea extract- (BTE-) induced collagen internalisation in human dermal fibroblasts (HDFs). LY294002, API2, U0126, SB203580, and SP600125 decreased BTE-induced collagen internalisation in HDFs. HDFs were treated with these inhibitors at the indicated concentrations for 1 h and then with BTE at 10 μg/mL for 1 day. Oregon Green™ 488-conjugated gelatin (OG-gelatin) internalisation was measured and calculated as described in the “Collagen Internalisation Measurement” section. The results are expressed as mean ± standard deviation of three independent experiments. Different letters indicate significant differences at .