Caco-2细胞缺氧复氧损伤时母乳对促炎细胞因子表达的影响

摘要

Objective To study the mechanisms of breast milk in preventing necrotizing enterocolitis (NEC) through the level of cellular and molecular biology. Methods We induced Caco-2 cells model of NEC after hypoxia/reoxygenation. The normal cell group and model cell of hypoxia/reoxygenation group was divided into three subgroups: ①conventional culture fluid; ②unheated breast milk supernatant fluid; ③heat-inactivated breast milk supernatant fluid. All cells were continually cultured for six hours, then we detected the expression of IL-1β, IL-6 and TNF-α proinflammatory cytokines secreted by Caco-2 cells in the nutrient fluid with ELISA method. Results In normal cell group, both unheated or heat-inactivated breast milk supernatant fluid could in-hibit the expression of IL-1β and IL-6. Compared with the heat-inactivated breast milk supernatant fluid, the inhibition effect of unheated breast milk supernatant fluid was better, and the difference had statistical significance. The expression of IL-1β, IL-6 and TNF-α was obvious after hypoxia/reoxygenation, and unheated or heat-inactivated breast milk supernatant fluid could inhibit the expression of IL-1β, IL-6, TNF-α with statistical significance. Compared with the heat-inactivated breast milk supernatant fluid, the inhibition effect of unheated breast milk supernatant fluid on the expression of IL-1β was more obvious. Conclusion Breast milk supernatant fluid can inhibit the expression of proinflammatory cytokines IL-1β, IL-6 as well as TNF-α in Caco-2 cells especially after hypoxia/reoxygenation, this may be one of the mechanisms of breast milk in preventing NEC.%目的：研究母乳对坏死性小肠结肠炎（necrotizing enterocolitis, NEC）炎症细胞的分子保护机制。方法通过建立Caco-2细胞缺氧复氧损伤模型，向正常细胞和缺氧复氧损伤模型细胞分别加入常规培养液、未加热乳清、加热灭活乳清。继续培养6 h后用ELISA法检测Caco-2细胞分泌于培养液中的促炎细胞因子IL-1β、IL-6、TNF-α水平。结果正常细胞组，未加热乳清和加热灭活乳清均可下调IL-1β、IL-6水平，未加热乳清较加热灭活乳清下调明显，两者之间差异有统计学意义；缺氧复氧损伤后IL-1β、IL-6、TNF-α均明显表达，未加热乳清和加热灭活乳清均可下调IL-1β、IL-6、TNF-α水平，差异有统计学意义，未加热乳清较加热灭活乳清下调IL-1β明显。结论母乳上清液可下调Caco-2炎症细胞促炎细胞因子IL-1β、IL-6的表达，尤其缺氧复氧损伤后TNF-α也下调明显，此类机制可能为母乳防治NEC的作用机制之一。