甘薯sporamin蛋白对3T3-L1前脂肪细胞分化和增殖的影响

Differentiation-and Proliferation-Inhibitory Effects of Sporamin from Sweetpotato on 3T3-L1 Preadipocytes

【目的】探讨甘薯sporamin蛋白对3T3-L1前脂肪细胞分化与增殖的影响,为开发预防和治疗肥胖、糖尿病的保健食品提供理论依据。【方法】采用硫酸铵沉淀、离子交换、凝胶过滤层析的方法对‘55-2’甘薯中的sporamin蛋白进行分离纯化。然后,以黄连素为阳性对照,用不同浓度sporamin(0、0.025、0.125、0.250、0.500、1.000mg·ml-1)处理3T3-L1前脂肪细胞。采用油红O染色和比色定量检测细胞内脂肪生成及细胞分化程度,以MTT法检测细胞的增殖。【结果】经离子交换、凝胶层析可纯化出高纯度的sporamin蛋白A和B(相对分子量分别为31kD和22kD)。与空白相比,用不同浓度的sporamin蛋白处理后,3T3-L1前脂肪细胞的分化受到明显抑制。当sporamin蛋白浓度增至0.500mg·ml-1时,脂滴生成量明显减少,洗脱液吸光度值降至最低为0.35(P<0.05)。此外,高浓度的sporamin蛋白能有效地抑制3T3-L1前脂肪细胞的增殖,且随着处理时间延长抑制效果更加明显(P<0.05).【结论】甘薯sporamin蛋白能抑制3T3-L1前脂肪细胞的分化和增殖,具有潜在的减肥作用。

[ Objective ] The aim of this study is to investigate the effect of different concentrations of sporamin on differentiation and proliferation of 3T3-L1 preadipocytes, providing a theoretical basis for the development of prevention and treatment of obesity and anti-diabetes reagent in food industry. [ Method ] Isolation and purification of sporamin from sweet potato 55-2 was performed by ammonium sulphate precipitation in combination with ion-exchange-, gel filtration chromatography. With berberine as a positive control, different concentrations of sporamin （0, 0.025, 0.125, 0.250, 0.500 and 1.000 mg·ml^-1, respectively） were used to treat 3T3-L1 preadipocytes. Intracellular fat accumulation and the degree of adipogenesis were observed using oil red O staining and quantified by colorimetry. Preadipocytes differentiation was measured by MTT spectrophotometry. [Result] Two sporamin proteins which were separated into sporamin A （31 kD） and sporamin B （22 kD） could be purified by ion-Exchange-, gel filtration chromatography. After being treated by different sporamin concentrations, the differentiation of 3T3-L1 preadipocytes was significantly inhibited compared with control. When the concentration of sporamin solution was 0.500mg·ml^-1, the accumulation of lipid droplets within the cells were obviously decreased and the optical density （OD） value of the solution from destained Oil Red O reached to 0.35, which was the lowest value （P〈0.05）. The proliferation of 3T3-L1 preadipocytes was significantly inhibited by treating at higher sporamin concentration. In addition, the restrictive effect was more obvious with the prolonging of treatment time （P〈0.05）. [Conclusion] Differentiation and proliferation of 3T3-L1 preadipocytes could be inhibited significantly by addition of higher concentration sporamin. It is, therefore, suggested that sporamin is effective for weight loss.