ABSTRACT
Objective:To explore the effect of celastrol in inhibiting the lipid metabolism disorder in hepatic L02 cells and its possible mechanism on endoplasmic reticulum stress (ERS) of non-alcoholic fatty liver cells by intervening non-alcoholic fatty liver disease(NAFLD) cell model with celastrol. Method:Hepatic L02 cells were divided into control group, model group, low-dose celastrol treatment group (Cel 0.5 mg·L-1), high-dose celastrol treatment group (Cel 1 mg·L-1) and simvastatin group (SIM 6 mg·L-1) for cultivation. The contents of total cholesterol (TC) and total triglyceride (TG) in hepatic L02 cells were detected, and the oil red staining was used to detected the lipid accumulation in hepatic L02 cells. Reverse transcription polymerase chain reaction (RT-PCR) and Western blot were used to detect the mRNA and protein expression levels of endoplasmic reticulum stress (ERS)-related signal molecules activating transcription factor 6 (ATF6), glucose regulated protein 78 (GRP78), inositol-requiring enzyme 1 (IRE1), sterol regulatory element-binding protein cleavage-activating protein (SCAP), sterol regulatory element-binding protein-1c (SREBP-1c) and sterol regulatory element-binding protein-2 (SREBP-2) in hepatic L02 cell model respectively. Result:The contents of TC and TG in hepatic L02 cells of NAFLD group were significantly higher than those in control group (P-1 group, Cel 1 mg·L-1 group and SIM 6 mg·L-1 group were significantly lower than those in NAFLD group (P-1 group, the Cel 1 mg·L-1 group, and the SIM 6 mg·L-1 group were lower than the NAFLD group to different degrees. According to the results of RT-PCR and Western blot, the mRNA transcription and protein expression levels of ERS-related signaling molecules ATF6, GRP78, IRE1, SCAP, SREBP-1c and SREBP-2 in hepatic L02 cells of NAFLD group were higher than those of control group (P-1 group, Cel 1 mg·L-1 group and SIM 6 mg·L-1 group were lower than those of NAFLD group (P-1 group and the SIM 6 mg·L-1 group. Conclusion:Celastrol can reduce the lipid metabolism disorder in hepatic L02 cells by down-regulating the expressions of ERS-related signaling molecules ATF6, GRP78, IRE1, SCAP, SREBP-1c and SREBP-2 in hepatic L02 cells, so as to improve NAFLD.