CAJ | 학술논문

目的：研究他莫昔芬（TAM）对体外培养的HepG2细胞脂肪变性以及脂类代谢调控关键因子表达的影响。方法应用油酸（50μmol/L）处理HepG2细胞，诱导细胞脂肪变性体外模型，同时给予不同浓度的TAM （5～20μmol/L）干预72 h；采用油红O染色和甘油三酯含量测定检测HepG2细胞内脂质聚集情况；应用蛋白印迹法检测固醇调节元件结合蛋白-1c（SREBP-1c）、脂肪酸合成酶（FAS）、硬脂酰辅酶A去饱和酶（SCD）、肉酯软脂酰基转移酶（CPT1）和微粒体甘油三酯转移蛋白（MTP）的表达；采用细胞活性检测试剂盒测定细胞活性。结果在干预72 h后，模型组细胞内甘油三酯含量为（16.53±0.17） mg/100 mg蛋白质，在5μmol/L TAM处理细胞内甘油三酯含量为（17.77±0.05） mg/100mg蛋白质，与模型组无显著性差异，但在10μmol/L和20μmol/L TAM处理组较模型组分别增加了31%[（21.57±0.16） mg/100 mg蛋白质]和44%[（23.82±0.44） mg/100 mg蛋白质]，（P<0.05）；TAM上调细胞内SREBP-1c、FAS、SCD和MTP蛋白表达，但并不改变CPT1蛋白表达；TAM在5～20μmol/L范围内不影响HepG2细胞活性。结论 TAM可促进油酸诱导的HepG2细胞脂肪变性，其主要机制可能是通过上调SREBP-1c及其下游基因，如FAS和SCD的表达而增加了脂肪酸的合成。
목적：연구타막석분（TAM）대체외배양적HepG2세포지방변성이급지류대사조공관건인자표체적영향。방법응용유산（50μmol/L）처리HepG2세포，유도세포지방변성체외모형，동시급여불동농도적TAM （5～20μmol/L）간예72 h；채용유홍O염색화감유삼지함량측정검측HepG2세포내지질취집정황；응용단백인적법검측고순조절원건결합단백-1c（SREBP-1c）、지방산합성매（FAS）、경지선보매A거포화매（SCD）、육지연지선기전이매（CPT1）화미립체감유삼지전이단백（MTP）적표체；채용세포활성검측시제합측정세포활성。결과재간예72 h후，모형조세포내감유삼지함량위（16.53±0.17） mg/100 mg단백질，재5μmol/L TAM처리세포내감유삼지함량위（17.77±0.05） mg/100mg단백질，여모형조무현저성차이，단재10μmol/L화20μmol/L TAM처리조교모형조분별증가료31%[（21.57±0.16） mg/100 mg단백질]화44%[（23.82±0.44） mg/100 mg단백질]，（P<0.05）；TAM상조세포내SREBP-1c、FAS、SCD화MTP단백표체，단병불개변CPT1단백표체；TAM재5～20μmol/L범위내불영향HepG2세포활성。결론 TAM가촉진유산유도적HepG2세포지방변성，기주요궤제가능시통과상조SREBP-1c급기하유기인，여FAS화SCD적표체이증가료지방산적합성。
Objective To investigate the effect of tamoxifen(TAM) on steatosis in HepG2 cells in vitro and on the expression of key regulators involved in lipid metabolism in the cells. Methods A cell model of steatosis was induced in HepG2 cells in vitro with oleic acid (OA) at 50 μmol/L;HepG2 cells were then subjected to dif-ferent concentrations of TAM (5 to 20 μmol/L) at the presence of OA for 72 h;Intracellular lipid accumulation was assessed by oil red O staining and measurement of triglyceride;The expression of sterol regulatory element-binding protein-1c(SREBP-1c),fatty acid synthase(FAS),steroyl-CoA desaturase(SCD),carnitine palmitoyltrans-ferase 1(CPT1)and mitochondrial trifunctional protein(MTP)was determined by Western blot;Cell viability was de-tected by cell counting Kit-8 assay. Results After incubation for 72 h,the intracellular triglyceride in control group was (16.53±0.17) mg/100 mg protein,similar to that of cells treated with 5μmol/L TAM,however,the intra-cellular triglyceride was increased by 31%[(21.57±0.16) mg/100 mg protein] and 44%[(23.82±0.44) mg/100 mg protein] in cells treated with 10 μmol/L and 20 μmol/L of TAM,respectively(P<0.05);TAM treatment(5 to 10 μmol/L) significantly increased the expression of SREBP-1c,FAS,SCD and MTP without affecting the expression of carni-tine palmitoyltransferase 1 (CPT1) in HepG2 cells;TAM did not affect HepG2 viability. Conclusions TAM pro-motes OA-induced cell steatosis,probably by up-regulation of SREBP-1c,FAS and SCD,thus increases fatty acid synthesis in the cells.