不同脂肪酸对脂肪细胞脂联素及PPARγ基因表达影响

Effects of different fatty acids on expression of adiponectin and PPARγ mRNA in 3T3-L1 adipocytes

目的用不同种类、不同浓度的脂肪酸处理体外培养的3T3-L1成熟脂肪细胞,观察处理前后脂联素(ad-iponectin)及过氧化物酶体增殖物激活受体γ(PPARγ)基因mRNA的表达水平,及两者之间是否存在相互关系。方法运用实时荧光定量PCR方法检测体外培养并诱导分化成熟的3T3-L1脂肪细胞经一定浓度脂肪酸处理后,脂联素及PPARγ基因mRNA的表达水平。结果棕榈酸(PA)在低浓度(25μmol/L)时能明显上调脂联素及PPARγmRNA的表达,比对照组增加53%(P<0.05),其余浓度均呈表达下降;油酸(OA)和亚油酸(LA)则在浓度为25、50、100μmol/L时上调脂联素及PPARγmRNA的表达,在50μmol/L时上调作用最为明显,随着浓度的继续增加脂联素表达下降,呈剂量依赖关系,浓度越高,表达越低。结论油酸和亚油酸在一定浓度范围内上调3T3-L1脂肪细胞脂联素基因表达,棕榈酸则主要表现为抑制作用,但在很低浓度(25μmol/L)时也上调脂联素表达;脂联素基因表达与PPARγ基因表达相关。

Objective To explore the effects of different fatty acids on the gene expression of adiponectin and peroxisome proliferator activated receptor γ（PPARγ） in 3T3-L1 adipocytes,and to assess the possible relationship between adiponectin and PPARγ.Methods After induced into adipocytes and identified by Oil Red O staining,the 3T3-L1 adipocytes were treated with palmitic acid（PA）,oleic acid（OA）,linoleic acid（LA） at different concentrations for 24 hours,and the gene expression of adiponectin mRNA and PPARγ mRNA were determined by real-time PCR.Results The mRNA expression of adiponectin and PPARγ in PA group were decreased in a dose-dependent manner,with a significant increase at 25 μmol/L（P〈0.05）.For OA and LA group,the expression of adiponectin and PPARγ increased at the dosages of 25,50,and 100 μmol/L,with the highest increase at 50 μmol/L（P〈0.05）.With the increase of fatty acid,the expression of adiponectin and PPARγ mRNA decreased in a dose-dependent manner.Conclusion Fatty acid could induce the gene expression of adiponectin and PPARγ mRNA in dose-dependent manner in 3T3-L1 adipocytes.PA could increase the gene expression of adiponectin and PPARγ even at low level of 25 μmol/L.The molecular mechanism of adiponectin gene expression might be correlated with a PPARγ activation signaling pathway,for there is a positive correlation between adiponectin and PPARγ.