胎儿脐血长链多不饱和脂肪酸水平与其部分免疫指标的关系

CORRELATIONS BETWEEN UMBILICAL CORD SERUM LONG-CHAIN POLYUNSATURATED FATTY ACIDS LEVELS AND IMMUNE INDICES

目的探讨脐血长链多不饱和脂肪酸水平与胎儿免疫功能的关系。方法招募身体健康、单胎妊娠的孕晚期妇女。分别采用气相色谱法、免疫抑制法、酶联免疫吸附试验(ELISA)法检测脐血中各长链多不饱和脂肪酸(LA、ALA、AA、EPA、DHA)、免疫球蛋白(IgG、IgA、IgM)、细胞因子(IFN-γ、IL-6)水平。结果多元线性回归分析显示,在校正可能混杂因素后,胎儿脐血ALA每增加1%,IgA、IgM分别增加0.035 g/L和0.294g/L,而脐血EPA每增加1%,IgA、IgM分别减少0.012和0.107g/L,Ln(IL-6)增加0.893 pg/ml;脐血DHA每增加1%,IFN-γ增加5.505 pg/ml,而n-6/n-3PUFA比值每增加1%,IFN-γ减少7.107 pg/ml。结论胎儿脐血ALA水平越高,IgA、IgM水平越高;而EPA水平越高,IgA、IgM水平越低,IL-6水平越高;IFN-γ水平随着DHA水平的升高而升高,且随着n-6/n-3PUFA比值的增大而降低,提示提高DHA摄入水平和降低n-6/n-3PUFA摄入比例有利于促进胎儿免疫功能成熟。

Objective To explore the associations between umbilical cord serum LC-PUFAs levels and immune indexes. Methods Healthy women with monocyesis at the third trimester were randomly selected as the participants. Umbilical cord serum LC-PUFAs（including LA, ALA, AA, EPA, DHA）, immunoglobulins（including IgG, IgA, IgM）, cytokines（IFN-γ, IL-6） were detected by gas chromatography, immunodepression, ELISA, respectively. Results Multiple linear regression analysis revealed that umbilical cord serum ALA level was positively related with IgA, IgM levels（β=0.035, P=0.000; β=0.294, P=0.005, respectively）, after adjustment for potential cofounders. A significant negative association was found between EPA and IgA, IgM（β=-0.012, P=0.014; β=-0.107, P=0.039, respectively）. For 1% additional increase of DHA, IFN-γ increased 5.505 pg/ml. n-6/n-3PUFA ratio was negatively related with IFN-γ level（β=-7.107, P=0.023）, and EPA level was positively related with IL-6 level（β=0.893,P=0.031） after adjustments of possible confounding factors. Conclusion Higher levels of ALA are correlated with higher IgA, IgM levels, while higher levels of EPA are correlated with lower IgA, IgM levels and higher IL-6 level. Increased DHA level and reduced n-6/n-3PUFA are also associated with increased IFN-γ level, suggesting that higher DHA and lower proportion of n-6/n-3PUFA intakes may benefit fetal immune function.