辣木异硫氰酸酯通过活化AMPK抑制3T3-L1脂肪细胞脂质积累

Moringa Isothiocyanate Inhibits Lipid Accumulation in 3T3-L1 Adipocytes by Activating AMPK

探究辣木异硫氰酸酯-4-[(α-L-rhamnosyloxy)benzyl]Isothiocyanates(MIC-1)抑制3T3-L1脂肪细胞脂质积累的作用及可能的调控机制。体外诱导3T3-L1前脂肪细胞分化为成熟脂肪细胞,用MIC-1干预48 h后检测细胞脂质积累情况,甘油三酯(TG)、甘油(Gly)和游离脂肪酸(FFA)含量;qRT-PCR检测脂代谢相关基因的表达;Western blot法测定腺苷酸活化蛋白激酶(AMPK)蛋白磷酸化水平和氧化物酶体增殖激活受体γ(PPARγ)蛋白表达水平。结果表明,MIC-1对3T3-L1前脂肪细胞存活率无影响;与对照组相比,MIC-1可降低脂肪细胞内脂滴分布及细胞着色程度,降低细胞内TG含量,减少FFA及甘油的溢出。MIC-1处理浓度达4μmol/L时,TG和FFA浓度分别下降64.00%和75.00%。同时,显著下调细胞中PPARγ(46.00%)、硬脂酰辅酶A去饱和酶1(SCD1)(62.00%)的mRNA表达水平;显著上调AMPK蛋白磷酸化水平(64.47%)和下调PPARγ(52.10%)蛋白表达水平。以上结果表明,MIC-1通过促进TG分解和抑制TG的合成,从而抑制脂质积累,其机制可能与AMPK的活化有关。

To explore the effect of Moringa isothiocyanate-4-[(α-L-rhamnosyloxy)benzyl]isothiocyanates(MIC-1)on the lipid accumulation in 3T3-L1 adipocytes and the possible regulatory mechanism,3T3-L1 preadipocytes were induced in vitro to differentiate into mature adipocytes.After 48 h of intervention with MIC-1,lipid accumulation,triglyceride(TG),glycerol(Gly)and free fatty acid(FFA)contents were determined;qRT-PCR was used to detect the expression of the genes related to lipid metabolism;Western blot was used to determine the phosphorylation level of adenylate-activated protein kinase(AMPK)and the expression level of oxisome proliferation-activated receptorγ(PPARγ).The results show that MIC-1 has no effect on the survival rate of 3T3-L1 preadipocytes;compared with the control group,MIC-1 can reduce the distribution of lipid droplets in adipocytes and the degree of cell coloration,intracellular TG content,and FFA and glycerol overflow.When the concentration of MIC-1 reached 4μmol/L,the concentration of TG and FFA decreased by 64%and 75%,respectively.At the same time,the mRNA expression levels of PPARγand stearoyl-CoA desaturase 1(SCD1)in cells were significantly down-regulated(by 46.00%and 62.00%,respectively);the protein expression levels of AMPK protein phosphorylation and down-regulated PPARγwere significantly up-regulated(by 64.47%and 52.10%,respectively).The above results indicate that MIC-1 inhibits lipid accumulation by promoting the decomposition of TG and inhibiting the synthesis of TG.The mechanism may be related to the activation of AMPK.