CAJ | 학술논문

目的：探讨糖皮质激素对关节软骨细胞衰老和自噬影响，并分析自噬在其中的作用及机制。方法：培养SD大鼠软骨细胞，阿利辛染色和collagen II免疫组化进行鉴定。使用不同浓度的地塞米松作用于软骨细胞不同的时间后，LysoTracker Red和MDC染色观察自噬囊泡的生成，Western blot检测LC3、beclin－1、P62、p70S6K和4EBP1蛋白表达的变化。β－半乳糖苷酶染色分析糖皮质激素对软骨细胞衰老的影响，并使用自噬抑制剂来探讨自噬对地塞米松作用下软骨细胞衰老的作用。结果：地塞米松可以显著提高软骨细胞的自噬水平，尤其是在作用4 d后，LC3－II表达随着地塞米松浓度的增加而升高，而P62和beclin－1的表达也验证自噬水平的升高。 LysoTracker Red和MDC染色发现软骨细胞中自噬泡的生成随着地塞米松浓度的升高而增加。 mTOR信号通路上的p70S6K和4EBP1的磷酸化均被地塞米松抑制。更重要的是，地塞米松可以引起软骨细胞的衰老，而使用3－MA抑制自噬后，细胞进一步衰老。结论：糖皮质激素激活软骨细胞中的自噬，并同时诱导软骨细胞的衰老，而自噬在这过程中对细胞的衰老可能具有代偿性的保护作用。同时糖皮质激素抑制mTOR信号通路，可能与自噬的激活相关。
목적：탐토당피질격소대관절연골세포쇠로화자서영향，병분석자서재기중적작용급궤제。방법：배양SD대서연골세포，아리신염색화collagen II면역조화진행감정。사용불동농도적지새미송작용우연골세포불동적시간후，LysoTracker Red화MDC염색관찰자서낭포적생성，Western blot검측LC3、beclin－1、P62、p70S6K화4EBP1단백표체적변화。β－반유당감매염색분석당피질격소대연골세포쇠로적영향，병사용자서억제제래탐토자서대지새미송작용하연골세포쇠로적작용。결과：지새미송가이현저제고연골세포적자서수평，우기시재작용4 d후，LC3－II표체수착지새미송농도적증가이승고，이P62화beclin－1적표체야험증자서수평적승고。 LysoTracker Red화MDC염색발현연골세포중자서포적생성수착지새미송농도적승고이증가。 mTOR신호통로상적p70S6K화4EBP1적린산화균피지새미송억제。경중요적시，지새미송가이인기연골세포적쇠로，이사용3－MA억제자서후，세포진일보쇠로。결론：당피질격소격활연골세포중적자서，병동시유도연골세포적쇠로，이자서재저과정중대세포적쇠로가능구유대상성적보호작용。동시당피질격소억제mTOR신호통로，가능여자서적격활상관。
AIM:Toexploretheeffectofglucocorticoidonautophagyandsenescenceinthechondrocytes. METHODS:The collagen II in the normal chondrocytes isolated from the SD rats was checked.After stimulation with glu-cocorticoid, LysoTracker Red staining, MDC staining and Western blot were used to detect the level of autophagy in the chondrocytes.The mTOR pathway related molecules were investigated by Western blot.Cell senescence was analyzed by SA-β-gal staining.RESULTS:A dose-dependent increase in the number of autophagic vacuoles was observed in the dexa-methasone-treated chondrocytes, which was demonstrated by the LysoTracker Red and MDC staining.The expression of LC3-II and beclin-1 was increased by dexamethasone, especially in the cells treated with dexamethasone for 4 d.However, P62 expression was decreased.SA-β-gal staining showed that the percentage of cell senescence was increased by dexam-ethasone.Surprisingly, the cell senescence induced by dexamethasone was exacerbated by the autophagic inhibitor 3-MA. CONCLUSION:Autophagy induced by dexamethasone protects chondrocyte from senescence.The mTOR pathway may be involved in the autophagy activation.