The effects and mechanisms of berberine on proliferation of papillary thyroid cancer K1 cells induced by high glucose / 中华内科杂志

ABSTRACT

Objective To study the effect and mechanisms of berberine (BBR) on the proliferation of papillary thyroid cancer K1 cells induced by high glucose.Methods K1 cells were cultured under 5.5 mmol/L or 25 mmol/L glucose condition with or without different concentration of BBR (0,10,40 and 80 μmol/L) for 24 hours.The proliferations of K1 cells in each condition were detected by MTT.Western blot was used to measure the expression of nuclear factor erythroid 2-related factor 2 (Nrt2),phosphoinositide 3-kinase (PI3K),protein kinase B (Akt) and phosphorylated-Akt (p-Akt).The distribution pattern of Nrf2 in K1 cells was determined using immunofluorescent staining.Results Compared with 5.5 mmol/L condition,the proliferation rate [(126.64 ± 5.41) ％ vs (87.31 ± 3.67) ％],expression levels of PI3K (0.425 ±0.019 vs 0.272 ±0.039),p-Akt/Akt (0.446 ±0.021 vs 0.168 ±0.035) and Nrf2 (0.597 ± 0.014 vs 0.308 ± 0.026),and Nrf2 distribution (93.0％ vs 23.1％) in nuclear of K 1 cells under 25 mmol/L condition were significantly elevated,respectively (all P ＜0.01).Addition of BBR in 25 mmol/L condition dose dependently (10,40,80 μmol/L) lowered the proliferation rate of K1 cells [(111.76 ± 4.10)％,(70.03 ±2.18)％,(32.41 ±3.76)％ vs (126.64 ±5.41)％,all P＜0.05],and suppressed the expression of PI3K,p-Akt/Akt,Nrf2,and Nrf2 nuclear distribution (P ＜ 0.05).Conclusions BBR dose dependently inhibited the proliferation of high glucose-induced K1 cells.This effect was associated with the suppression on of PI3K/Akt signaling activation,Nrf2 expression and its nuclear translocation.