EPA对草鱼前体脂肪细胞增殖分化的影响

EFFECTS OF EPA ON THE PROLIFERATION AND DIFFERENTIATION OF GRASS CARP PREADIPOCYTES

体外培养草鱼前体脂肪细胞,并用不同浓度(0—100μmol/L)二十碳五烯酸(Eicosapentaenoic acid,EPA)进行处理,噻唑兰比色法(Methyl thiazolte trazoliu,MTT)和油红O染色提取法检测EPA对细胞增殖及分化的影响,Real-time qPCR检测过氧化物酶增殖激活受体家族(Peroxidase proliferation activated receptor,PPARs)、脂蛋白酯酶(Lipoprotein lipase,LPL)、过氧化物酶体增殖激活受体γ辅助活化因子1α(Peroxisome prolifera-toractivated receptor gamma coactivator-1α,PGC-1α)等基因的表达情况。结果显示,不同浓度EPA在2d内均显著促进草鱼前体脂肪细胞增殖(P<0.05);不同浓度EPA处理1d后均显著抑制草鱼前体脂肪细胞分化(P<0.05),且100μmol/L EPA处理细胞2d可显著促进LPL和PGC-1α基因的表达(P<0.05)。研究表明,EPA可促进草鱼前体脂肪细胞增殖,抑制其分化,该抑制作用与其调控PGC-1α、LPL等脂代谢基因的表达有关。

We investigated the effects of eicosapentaenoic acid （EPA） on proliferation, differentiation and gene expression of lipid metabolism in grass carp （Ctenopharyngodon idellus） preadipocytes. The developmental process of grass carp preadipocytes was observed at 0, 4, 6 and 14d after seeding. The proliferation of the preadipocytes was detected by methyl thiazolyl tetrazolium （MTT） assay method. The differentiation degree of cell was detected by oil red O staining after treated with 0-100 μmol/L EPA. The cell was treated with 100 μmol/L for two days after the cell confluence, and then RNA was isolated. The expression of peroxisome proliferation activated receptors （PPARs）, lipoprotein lipase （LPL） and peroxisome proliferatoractivated receptor gamma coactivator-1α （PGC-1α） were detected by real-time PCR. The results showed that grass carp preadipocytes could reach confluence on seeding for six days in growth medium. The proliferation of preadipocytes was significantly promoted after EPA treatment with various levels for two days （P〈0.05）, and the promotion effect disappeared at 3d. In comparison with the control group, intracellular lipid accumulation was significantly decreased at 1d following the addition of EPA （P〈0.05）. At the same time, the mRNA level of LPL and PGC-1α were also significantly elevated after treated with 100 μmol/L EPA for two days （P〈0.05）, but there was no significant difference of the gene expression of PPARs observed between groups. It could be concluded that EPA enhanced the proliferation and inhibited the differentiation of grass carp preadipocytes. The suppression function of EPA on adipocytes differentiation and lipid accumulation might be related to its regulation on the expression of the lipid-metabolism-related genes, such as PGC-1α and LPL.