黄芩茎叶总黄酮对U937细胞脂代谢的影响

Effects of Total Flavonoids Extracted from Scutellaria's Stems and Leaves on Lipid Metabolism in U937 Cells

目的研究黄芩茎叶总黄酮(TF)对人类单核肿瘤细胞U937脂质代谢的影响。方法取2块24孔板,每孔中接种U937细胞2.5×106个/mL,培养液中含胎牛血清(FCS)10%、LDL 100 mg/L、佛波酯(PMA)100μg/L和不同浓度的TF,根据TF浓度不同分为TF 0,25,50,100,150,200 mg/L 6组,每组8孔,37℃、5%CO2、饱和湿度培养72 h,收集培养细胞测定细胞内总胆固醇(TCH)含量和蛋白质量,细胞涂片油红O染色观察细胞内脂质蓄积情况,测定细胞培养液中Ox-LDL的浓度。结果油红O染色观察,细胞内脂质颗粒随TF浓度的增加而呈减少趋势。TF 0～200 mg/L组细胞内每克蛋白的TCH含量(mg/g)分别为520.13±37.52,375.39±39.78,366.49±35.76,254.26±25.55,263.55±27.72,249.23±22.69,差别具有显著性(F=86.36,P<0.001)。细胞培养液中Ox-LDL浓度分别为0.2113±0.023,0.1938±0.045,0.1288±0.041,0.1238±0.013,0.0850±0.021,0.1429±0.053 mg/mL,差别有极显著性(F=40.73,P<0.0001)。结论 TF可抑制LDL氧化,减少U937细胞内胆固醇的蓄积,抑制泡沫细胞的形成。

Objective To investigate the effects of total flavonoids（TF）on lipid metabolism in U937 cells.Methods U937 cells cultured in two 24-well plate（2.5×10^6/mL）were divided into 6 groups according to TF concentration in culture medium.They were TF 0 mg/L,TF 25 mg/L,TF 50 mg/L,TF 100 mg/L,TF 150 mg/L,and TF 200 mg/L,8 wells for each concentration.U937 cells were incubated in the medium with fetal calf serum（FCS）10 %,LDL 100 mg/L,phorbol ester（PMA）100 μg/L and TF（in different concentrations）under the condition of 37 ℃,5 %CO2,and saturated humidity for 72 hours.Then,cellular total cholesterol（TCH）contents,cellular protein contents and Ox-LDL concentrations in culture mediums were measured,and morphological features were observed by oil red O staining technique.Results The results of oil red staining showed that lipid droplets could be seen in the cells of each group.The number of lipid droplets decreased with the increased of TF concentration.Descending rank of TCH（mg/g cell protein）in the TF 0～200 mg/L groups were TF 0 mg/L（520.13 ± 37.52）,TF 25 mg/L（375.39 ± 39.78）,TF 50 mg/L（366.49 ± 35.76）,TF 150 mg/L（263.55 ± 27.72）,TF 100 mg/L（254.26 ± 25.55）,and TF 200 mg/L（249.23 ± 22.69）.The difference were significant between the 6 groups（F=86.36,P〈0.001）.Ox-LDL concentration of culture medium was 0.1288 ± 0.041,0.1238 ± 0.013,0.0850 ± 0.021,0.1429 ± 0.053 mg/mL in TF 50～200 mg/L groups,and was 0.2113 ± 0.023,0.1938 ± 0.045 mg/mL in TF 0～25 mg/L groups,respectively.The difference was significant（F = 40.73,P〈0.0001）.Conclusion TF inhibits the oxidation of LDL,reduces the accumulation of cellular TCH,and depresses the formation of macrophage-derived foam cells.