中文摘要：

目的探讨机械应力调控软骨细胞炎症反应的作用机制。方法体外分离培养新生SD大鼠软骨细胞，经白介素-1β（IL—1β）干预构建软骨细胞炎症模型，设置对照组（IL-1β）、2000μstrain组（2000μstrain应力＋IL-1β）、5000μstrain组（5000μstrain应力＋IL-10），IL-1β浓度为5ng／ml，以1Hz应力干预2h。采用Real—timePCR和Western Blot检测Ⅱ型胶原（C01．2）、基质金属蛋白酶13（MMP13）、自噬标记蛋白LC3、Beclin-1及n1．TOR表达，同时检测MEG3表达，采用免疫荧光染色检测自噬小体形成；si＋RNA沉默MEG3后，采用Real—timePCR检测LC3及Beclin-1表达。结果2000μstrain组软骨细胞Col-2、LC3、Beelin-1基因及Beelin-1蛋白表达量均较对照组及5000μstrain组明显上调（P〈0．05）；2000μstrain组软骨细胞MEG3基因表达量较对照组及5000μstrain组明显下调（P〈0．05）；5000μstrain组In—TOR蛋白表达较对照组及2000μstrain组明显增加（P〈0．05）；应力组自噬标记蛋白LC3Ⅱ／Ⅰ相对表达量均较对照组明显减少（P〈0．05）；免疫荧光染色显示2000μstrain组自噬小体形成较对照组及5000μstrain组明显增加，5000μstrain组自噬小体形成较对照组及2000μstrain组明显减少（P〈0．05）；si—RNA沉默MEG3后，发现LC3及Beclin-1表达量均明显增加（P〈0．05）。结论机械应力可影响软骨细胞LncRNA—MEG3表达，从而调控炎症环境中软骨细胞自噬水平。

英文摘要：

Objective To explore the mechanism by which mechanical strain regulates the inflammatory re- sponses of chondrocytes. Methods Chondrocytes were harvested from newborn Sprague-Dawley rats and cultured in vitro. The chondrocytes were subjected to 2000 μ strain or 5000 μ strain mechanical strain at a frequency of 1 Hz for 2 h. Real-time PCR and western blotting were used to detect the expression of collagen type 11 （Col-2） , matrix met- alloproteinase （MMP13） , and autophagy marker proteins LC3 and Beclin-1. The expression of LncRNA-MEG3 was detected simultaneously. Immunofluorescence was used to detect the expression of LC3 and Beclin-1 after real-time PCR when LncRNA-MEG3 had been silenced by si-RNA. Results The expression of the Col-2 and LC3 genes was significantly up-regulated in IL-lβ-treated chondrocytes subjected to 2000 μ strain mechanical strain. The level of the autophagy marker protein LC3 Ⅱ / I in the strained group was significantly higher than that in the control group. The expression of Beclin-I and m-TOR in the strain-stressed group was significantly higher than in the control group, lm- munoflunrescence staining showed that the expression of LC3 in the 2000 μ strain group was significantly higher than that in the control group, while in the 5000 μ strain group it was significantly lower. The expression of LC3 was significantly increased after silencing LncRNA-MEG3 using si-RNA. Conclusion Mechanical strain regulates the autophagy of chondrocytes in an inflammatory environment by regulating the expression of LncRNA-MEG3.