n-6和n-3多不飽和脂肪酸對(duì)心肌缺血/再灌注損傷炎癥因子TNF-α和IL-1釋放的影響

呂珩 鮑麗剛

[摘要] 目的 探討n-6和n-3多不飽和脂肪酸對(duì)心肌缺血/再灌注損傷炎癥因子TNF-α和IL-1釋放的抑制作用及其抗炎作用機(jī)制。 方法 構(gòu)建健康成年SD大鼠4組模型（sham、IR、n-3 PUFA+IR和n-6 PUFA+IR），通過肌酸激酶（CK）、肌酸激酶同工酶（CK-MB）和乳酸脫氫酶（LDH）活性檢測(cè)缺血/再灌注的損傷程度;通過酶聯(lián)免疫吸附測(cè)定促炎細(xì)胞因子TNF-α、IL-1的表達(dá)水平;通過qPCR和Western blot檢測(cè)TLR4/NF-κB的表達(dá)水平。 結(jié)果 與IR組相比，n-3 PUFA+IR和n-6 PUFA+IR組的CK、CK-MB和LDH顯著降低，心肌梗死面積減少，心肌組織形態(tài)學(xué)結(jié)構(gòu)改善;ELISA檢測(cè)發(fā)現(xiàn)n-6和n-3 PUFAs處理組，TNF-α、IL-1的表達(dá)水平顯著降低;TLR4、NF-κB的mRNA和蛋白的表達(dá)也顯著降低。 結(jié)論 n-3 PUFA和n-6 PUFA通過TLR4/NF-κB途徑抑制促炎因子TNF-α和IL-1的表達(dá)，從而保護(hù)心肌缺血/再灌注損傷，TLR4介導(dǎo)的NF-κB信號(hào)傳導(dǎo)途徑可能成為心肌缺血/再灌注損傷的新策略。

[關(guān)鍵詞] 心肌缺血/再灌注損傷;n-3和n-6多不飽和脂肪酸;炎癥因子;TLR4 /NF-κB

[中圖分類號(hào)] R285 ? ? ? ? ?[文獻(xiàn)標(biāo)識(shí)碼] A ? ? ? ? ?[文章編號(hào)] 1673-9701（2019）14-0031-06

[Abstract] Objective To investigate the inhibitory effects of n-6 and n-3 polyunsaturated fatty acids on the release of inflammatory cytokines TNF-α and IL-1 in myocardial ischemia/reperfusion injury and its anti-inflammatory mechanism. Methods Four sets of models of healthy adult SD rats（sham， IR， n-3 PUFA+IR， and n-6 PUFA+IR） were constructed. The degree of ischemia-reperfusion injury was measured by activity of creatine kinase（CK）， creatine kinase isoenzyme （CK-MB） and lactate dehydrogenase （LDH）; The expression levels of pro-inflammatory cytokines TNF-α and IL-1 were determined by enzyme-linked immunosorbent assay. The expression levels of TLR4/NF-κB were detected by qPCR and Western blot. Results Compared with the IR group， CK， CK-MB and LDH were significantly lower in the n-3 PUFA+IR and n-6 PUFA+IR groups， the myocardial infarct size was reduced， and the myocardial histomorphology was improved. ELISA showed that the expression levels of TNF-α and IL-1 in n-6 and n-3 PUFAs groups were significantly decreased; the mRNA and protein expression of TLR4 and NF-κB were also significantly decreased. Conclusion n-3 PUFA and n-6 PUFA inhibit the expression of pro-inflammatory factors TNF-α and IL-1 through the TLR4/NF-κB pathway， thereby protecting myocardial ischemia/reperfusion injury. TLR4-mediated NF-κB signaling pathway may be a new strategy for myocardial ischemia/reperfusion injury.

[Key words] Myocardial ischemia/reperfusion injury; n-3 and n-6 polyunsaturated fatty acids; Inflammatory factors; TLR4/NF-κB

目前，缺血性心臟病的最佳治療策略為心肌再灌注，它可以通過逆轉(zhuǎn)心肌缺血和限制梗死面積來保持心肌的活力和功能[1-2]。然而，隨后出現(xiàn)的缺血/再灌注（I/R）損傷可能會(huì)降低治療效果[3]。心肌I/R是一個(gè)復(fù)雜的病理生理過程，涉及各種因素和途徑[4]，炎癥反應(yīng)被認(rèn)為是I/R誘導(dǎo)的組織損傷的主要原因[5]，有實(shí)驗(yàn)及臨床證據(jù)表明抗炎作用可以減輕I/R損傷[6]。

Toll樣受體4（TLR4）作為模式識(shí)別受體的成員，通過識(shí)別外源性病原體相關(guān)分子模式和內(nèi)源性配體，在誘導(dǎo)炎癥反應(yīng)中發(fā)揮重要作用[7-8]。TLR4的激活與幾種細(xì)胞類型中促炎細(xì)胞因子的表達(dá)和NF-κB信號(hào)傳導(dǎo)途徑的激活有關(guān)[9-10]。有研究表明，與野生型相比，缺血/再灌注后TLR4敲除和TLR4突變小鼠均表現(xiàn)出較少的心肌損傷和炎癥[11-12]，還發(fā)現(xiàn)TLR4表達(dá)與心肌I/R大鼠模型中的腫瘤壞死因子-α（TNF-α）和白細(xì)胞介素-1（IL-1）水平呈正相關(guān)[13]。