Tea and Citrus maxima complex induces apoptosis of human liver cancer cells via PI3K/AKT/mTOR pathway in vitro

Objective:In this study,black tea and Citrus maxima(BT-CM),yellow tea and C.maxima(YT-CM),green tea and C.maxima(GT-CM)as subjects,the active ingredient content and antioxidant activity of three tea and C.maxima(T-CM)were analyzed.The effects of three T-CMs on apoptosis of liver cells in vitro and its mechanism were further explored.Methods:National standard method and HPLC were used for active ingredient analysis.MTT,cell fow cytometry and Western blot were used to analyze the effects of three T-CMs on cell proliferation,apoptosis,and its underlying molecular mechanism.Results:The content of tea polyphenols,free amino acids,ratio of polyphenols and amino acids,ester catechins,non-ester catechins and caffeine in YT-CM and GT-CM was significantly higher than that of BT-CM.The in vitro antioxidant capacity of YT-CM and GT-CM was also significantly stronger than that of BT-CM.Three T-CMs had the effects of inhibiting proliferation,arresting cell cycle and inducing apoptosis in HepG2 and Bel7402 cells,especially YT-CM and GT-CM.Western blot analysis showed three T-CMs activated PI3K/AKT/mTOR signaling pathway and regulated the expression levels of apoptosis-related proteins Bax,Bcl-2 and Caspase-3/9.YT-CM and GT-CM had better ability to change the signal pathway than BT-CM.Conclusion:In short,T-CMs,which combined different degrees of fermentation tea with C.maxima,were rich in nutrients and biologically active substances.T-CMs,especially YT-CM and GT-CM,are healthy drinks that help to prevent and treat liver cancer.