Background:Ossification of the posterior longitudinal ligament(OPLL)is a prevalent condition in orthopedics.While death-associated protein kinase 2(DAPK2)is known to play roles in cellular apoptosis and autophagy,its ...Background:Ossification of the posterior longitudinal ligament(OPLL)is a prevalent condition in orthopedics.While death-associated protein kinase 2(DAPK2)is known to play roles in cellular apoptosis and autophagy,its specific contributions to the advancement of OPLL are not well understood.Methods:Ligament fibroblasts were harvested from patients diagnosed with OPLL.Techniques such as real-time reverse transcriptasepolymerase chain reaction(RT-qPCR)and Western blot analysis were employed to assess DAPK2 levels in both ligament tissues and cultured fibroblasts.The extent of osteogenic differentiation in these cells was evaluated using an alizarin red S(ARS)staining.Additionally,the expression of ossification markers and autophagy markers was quantified.The autophagic activity was further analyzed through LC3 immunofluorescence and transmission electron microscopy(TEM).An in vivo heterotopic bone formation assay was conducted in mice to assess the role of DAPK2 in ossification.Results:Elevated DAPK2 expression was confirmed in both OPLL patient tissues and derived fibroblasts,in contrast to non-OPLL controls.Silencing of DAPK2 significantly curtailed osteogenic differentiation and autophagy in these fibroblasts,evidenced by decreased levels of LC3,and Beclin1,and reduced autophagosome formation.Additionally,DAPK2 was found to inhibit the mechanistic target of the rapamycin complex 1(mTORC1)complex’s activity.In vivo studies demonstrated that DAPK2 facilitates ossification,and this effect could be counteracted by the mTORC1 inhibitor rapamycin.Conclusion:DAPK2 enhances autophagy and osteogenic processes in OPLL through modulation of the mTORC1 pathway.展开更多
目的观察银盏心脉滴丸对大鼠心肌细胞(H9C2)mTORC1/4EBP1信号通路的影响以探讨其对线粒体功能的机制。方法制备银盏心脉滴丸含药血清。将细胞分为对照组、模型组(缺氧/复氧)、空白血清组及银盏心脉滴丸含药血清组。制备缺氧/复氧细胞损...目的观察银盏心脉滴丸对大鼠心肌细胞(H9C2)mTORC1/4EBP1信号通路的影响以探讨其对线粒体功能的机制。方法制备银盏心脉滴丸含药血清。将细胞分为对照组、模型组(缺氧/复氧)、空白血清组及银盏心脉滴丸含药血清组。制备缺氧/复氧细胞损伤模型,利用激光共聚焦检测线粒体膜电位(ΔΨm),利用流式细胞仪检测活性氧(reactive oxygen species, ROS),运用Western Blot技术检测细胞雷帕霉素靶蛋白(mammalian target of rapamycin, mTOR)、真核翻译起始因子4E结合蛋白(eukaryotic translation initiation factor 4E-binding proteins,4E-BP)、mTOR复合体蛋白(regulatory-associated protein of mammalian target of rapamycin,Raptor)蛋白表达,运用q-PCR方法检测mTORC1、4EBP1、Raptor的mRNA含量。结果与对照组相比,模型组细胞内绿色荧光增强,ΔΨm显著高于对照组(P<0.05);而与模型组相比,银盏心脉滴丸组红色荧光增强(P<0.05),说明银盏心脉保护ΔΨm稳定,保护线粒体膜结构;与对照组相比,模型组的ROS合成较对照组升高(P<0.05);而与模型组相比,银盏心脉滴丸组细胞内ROS产生明显降低(P<0.05);与对照组相比,模型组mTOR、Raptor基因mRNA水平下调(P<0.05),4ebp1基因mRNA水平上调,差异有统计学意义(P<0.05)。与模型组比较,银盏心脉滴丸组mTOR、Raptor基因mRNA水平上调(P<0.05),4ebp1基因mRNA水平下调(P<0.05)。结论银盏心脉滴丸改善缺氧复氧损伤的机制可能是通过激活mTORC1/4EBP1信号通路,从而抑制线粒体膜电位,改善活性氧,保护线粒体功能。展开更多
基金This research received funding from the Natural Science Foundation of Shanghai(Grant No.20ZR1457600)the School-Level Basic Medical Project of Naval Medical University(Grant No.2021MS13).
文摘Background:Ossification of the posterior longitudinal ligament(OPLL)is a prevalent condition in orthopedics.While death-associated protein kinase 2(DAPK2)is known to play roles in cellular apoptosis and autophagy,its specific contributions to the advancement of OPLL are not well understood.Methods:Ligament fibroblasts were harvested from patients diagnosed with OPLL.Techniques such as real-time reverse transcriptasepolymerase chain reaction(RT-qPCR)and Western blot analysis were employed to assess DAPK2 levels in both ligament tissues and cultured fibroblasts.The extent of osteogenic differentiation in these cells was evaluated using an alizarin red S(ARS)staining.Additionally,the expression of ossification markers and autophagy markers was quantified.The autophagic activity was further analyzed through LC3 immunofluorescence and transmission electron microscopy(TEM).An in vivo heterotopic bone formation assay was conducted in mice to assess the role of DAPK2 in ossification.Results:Elevated DAPK2 expression was confirmed in both OPLL patient tissues and derived fibroblasts,in contrast to non-OPLL controls.Silencing of DAPK2 significantly curtailed osteogenic differentiation and autophagy in these fibroblasts,evidenced by decreased levels of LC3,and Beclin1,and reduced autophagosome formation.Additionally,DAPK2 was found to inhibit the mechanistic target of the rapamycin complex 1(mTORC1)complex’s activity.In vivo studies demonstrated that DAPK2 facilitates ossification,and this effect could be counteracted by the mTORC1 inhibitor rapamycin.Conclusion:DAPK2 enhances autophagy and osteogenic processes in OPLL through modulation of the mTORC1 pathway.
文摘目的观察银盏心脉滴丸对大鼠心肌细胞(H9C2)mTORC1/4EBP1信号通路的影响以探讨其对线粒体功能的机制。方法制备银盏心脉滴丸含药血清。将细胞分为对照组、模型组(缺氧/复氧)、空白血清组及银盏心脉滴丸含药血清组。制备缺氧/复氧细胞损伤模型,利用激光共聚焦检测线粒体膜电位(ΔΨm),利用流式细胞仪检测活性氧(reactive oxygen species, ROS),运用Western Blot技术检测细胞雷帕霉素靶蛋白(mammalian target of rapamycin, mTOR)、真核翻译起始因子4E结合蛋白(eukaryotic translation initiation factor 4E-binding proteins,4E-BP)、mTOR复合体蛋白(regulatory-associated protein of mammalian target of rapamycin,Raptor)蛋白表达,运用q-PCR方法检测mTORC1、4EBP1、Raptor的mRNA含量。结果与对照组相比,模型组细胞内绿色荧光增强,ΔΨm显著高于对照组(P<0.05);而与模型组相比,银盏心脉滴丸组红色荧光增强(P<0.05),说明银盏心脉保护ΔΨm稳定,保护线粒体膜结构;与对照组相比,模型组的ROS合成较对照组升高(P<0.05);而与模型组相比,银盏心脉滴丸组细胞内ROS产生明显降低(P<0.05);与对照组相比,模型组mTOR、Raptor基因mRNA水平下调(P<0.05),4ebp1基因mRNA水平上调,差异有统计学意义(P<0.05)。与模型组比较,银盏心脉滴丸组mTOR、Raptor基因mRNA水平上调(P<0.05),4ebp1基因mRNA水平下调(P<0.05)。结论银盏心脉滴丸改善缺氧复氧损伤的机制可能是通过激活mTORC1/4EBP1信号通路,从而抑制线粒体膜电位,改善活性氧,保护线粒体功能。
