目的通过观察地高辛(Digoxin)干预血管紧张素Ⅱ(AngⅡ)诱导的ApoE-/-小鼠高血压性心肌肥厚模型后,对G蛋白调节因子2(regulator of G protein signaling 2,RGS2)的影响,探讨地高辛治疗高血压性心肌肥厚的作用与可能的机制。方法 30只雄性...目的通过观察地高辛(Digoxin)干预血管紧张素Ⅱ(AngⅡ)诱导的ApoE-/-小鼠高血压性心肌肥厚模型后,对G蛋白调节因子2(regulator of G protein signaling 2,RGS2)的影响,探讨地高辛治疗高血压性心肌肥厚的作用与可能的机制。方法 30只雄性ApoE-/-小鼠随机分为对照组、AngⅡ模型组和AngⅡ+Digoxin治疗组。所有小鼠从术前1d至术后处死前均接受0.5%二甲基亚砜或地高辛溶液腹腔注射治疗,并且在术后28d获取心脏组织,通过组织学检查、苏木精-伊红(HE)染色切片分析技术评定心肌组织形态学变化、RGS2的mRNA及蛋白表达水平来评价地高辛的作用。结果与AngⅡ模型组相比,AngⅡ+Digoxin组全心重量、左心室壁厚度、心肌细胞直径均明显减少(P<0.05或P<0.01),RGS2mRNA变化不明显,而蛋白表达增高(P<0.01),心肌肥厚明显减轻。同时检测小鼠在术前3d,手术当天,术后3、7、14、28d的血压,发现AngⅡ+Digoxin组与AngⅡ模型组比较,术后7d和14d血压下降(均P<0.05),术后28d则差异无统计学意义。结论地高辛可能通过上调ApoE-/-小鼠高血压心肌肥厚模型RGS2的表达,有效减轻心肌肥厚,这说明地高辛可能在抑制心肌细胞肥大中起重要作用。展开更多
Summary： The main pathogenesis of saphenous vein graft neointimal hyperplasia after coronary artery bypass grafting （CABG） is inflammation-caused migration and proliferation of vascular smooth muscle cells （VSMCs...Summary： The main pathogenesis of saphenous vein graft neointimal hyperplasia after coronary artery bypass grafting （CABG） is inflammation-caused migration and proliferation of vascular smooth muscle cells （VSMCs）. Janus kinase 2/signal transducer and activators of transcription 3 （JAK2/STAT3） path- way is an important signaling pathway through which VSMCs phenotype conversion occurs. Suppressor of cytokine signaling 3 （SOCS3） is the classic negative feedback inhibitor of JAK2/STAT3 pathway. Growing studies show that SOCS3 plays an important anti-inflammatory role in numerous autoimmune diseases, inflammatory diseases and inflammation-related tumors. However, the effect and mechanism of SOCS3 on vein graft disease is unclear. The purpose of this study was to investigate the effects of SOCS3 on the inflammation, migration and proliferation of VSMCs in vitro and the mechanism. The small interference RNA plasmid targeting rat SOCS3 （SiRNA-rSOCS3） and the recombinant adenovirus vector carrying rat SOCS3 gene （pYrAd-rSOCS3） were constructed, and the empty plamid （SiRNA-control） and vector （pYrAd-GFP） only carrying GFP reported gene were constructed as control. The rat VSMCs were cultured. There were two large groups of A （SOCS3 up-regulated）： control group, IL-6/IFN-γ group, IL-6/IFN-γ＋pYrAd-rSOCS3 group, IL-6/IFN-γ＋pYrAd-GFP group; and B （SOCS3 down-regulated）： control group, IL-6/IFN-γ group, IL-6/IFN-γ＋SiRNA-rSOCS3 group and IL-6/IFN -T＋SiRNA-control group. The pYrAd-rSOCS3 and SiRNA-rSOCS3 were transfected into VSMCs in- duced by IL-6/IFN-γ. After 24 h, real-time reverse transcription polymerase chain reaction （RT-PCR） and Western blotting were used to detect the mRNA and protein expression of SOCS3, STAT3 （only by Western blotting）, P-STAT3 （only by Western blotting）, IL-1β, IL-6, TNF-α, MCP-1 and ICAM-1. The MTT, Transwell assay and flow cytometry were used to examine VSMCs proliferation, migration and cell cycle progression, respectively. As compared with control group, the mRNA and protein expression of SOCS3, STAT3, P-STAT3, IL-1β, IL-6, TNF-α, MCP-1 and ICAM-1 was significantly up-regulated in VSMCs stimulated by IL-6/IFN-γ. However, in VSMCs transfected with pYrAd-rSOCS3 before stimulation with IL-6/IFN-γ, the expression of SOCS3 mRNA and protein was further up-regulated, and that of STAT3, P-STAT3, IL-1β, IL-6, TNF-α, MCP-1 and ICAM-1 was significantly down-regulated as compared with IL-6/IFN-γ group and IL-6/IFN-γ＋pYrAd-GFP group. The expression of those re- lated-cytokines in IL-6/IFN-γ＋SiRNA-rSOCS3 group was markedly increased as compared with IL-6/IFN-γ group and IL-6/IFN-γ＋SiRNA-control group. The absorbance （A） values, the number of cells migrating to the lower chamber, and percentage of cells in the G2/M＋S phase were increased in VSMCs stimulated by IL-6/IFN-γ. In VSMCs incubated with pYrAd-rSOCS3 or SiRNA-rSOCS3 be- fore IL-6/IFN-γ stimulation, the A values, the number of cells migrating to the lower chamber, and the percentage of cells in the G2/M＋S phase were significantly decreased, and increased respectively. These results imply that IL-6/IFN-γ, strong inflammatory stimulators, can promote transformation of VSMCs phenotype form a quiescent contractile state to a synthetic state by activating JAK2/STAT3 pathway. Over-expresssed SOCS3 might inhibit pro-inflammatory effect, migration and growth of VSMCs by blocking STAT3 activation and phosphorylation. These data in vitro confirm that SOCS3 may play a negatively regulatory role in development and progression of vein graft failure. These conclusions can provide a novel strategy for clinical treatment of vein graft diseases and a new theoretic clue for related drug development.展开更多
文摘目的通过观察地高辛(Digoxin)干预血管紧张素Ⅱ(AngⅡ)诱导的ApoE-/-小鼠高血压性心肌肥厚模型后,对G蛋白调节因子2(regulator of G protein signaling 2,RGS2)的影响,探讨地高辛治疗高血压性心肌肥厚的作用与可能的机制。方法 30只雄性ApoE-/-小鼠随机分为对照组、AngⅡ模型组和AngⅡ+Digoxin治疗组。所有小鼠从术前1d至术后处死前均接受0.5%二甲基亚砜或地高辛溶液腹腔注射治疗,并且在术后28d获取心脏组织,通过组织学检查、苏木精-伊红(HE)染色切片分析技术评定心肌组织形态学变化、RGS2的mRNA及蛋白表达水平来评价地高辛的作用。结果与AngⅡ模型组相比,AngⅡ+Digoxin组全心重量、左心室壁厚度、心肌细胞直径均明显减少(P<0.05或P<0.01),RGS2mRNA变化不明显,而蛋白表达增高(P<0.01),心肌肥厚明显减轻。同时检测小鼠在术前3d,手术当天,术后3、7、14、28d的血压,发现AngⅡ+Digoxin组与AngⅡ模型组比较,术后7d和14d血压下降(均P<0.05),术后28d则差异无统计学意义。结论地高辛可能通过上调ApoE-/-小鼠高血压心肌肥厚模型RGS2的表达,有效减轻心肌肥厚,这说明地高辛可能在抑制心肌细胞肥大中起重要作用。
文摘Summary： The main pathogenesis of saphenous vein graft neointimal hyperplasia after coronary artery bypass grafting （CABG） is inflammation-caused migration and proliferation of vascular smooth muscle cells （VSMCs）. Janus kinase 2/signal transducer and activators of transcription 3 （JAK2/STAT3） path- way is an important signaling pathway through which VSMCs phenotype conversion occurs. Suppressor of cytokine signaling 3 （SOCS3） is the classic negative feedback inhibitor of JAK2/STAT3 pathway. Growing studies show that SOCS3 plays an important anti-inflammatory role in numerous autoimmune diseases, inflammatory diseases and inflammation-related tumors. However, the effect and mechanism of SOCS3 on vein graft disease is unclear. The purpose of this study was to investigate the effects of SOCS3 on the inflammation, migration and proliferation of VSMCs in vitro and the mechanism. The small interference RNA plasmid targeting rat SOCS3 （SiRNA-rSOCS3） and the recombinant adenovirus vector carrying rat SOCS3 gene （pYrAd-rSOCS3） were constructed, and the empty plamid （SiRNA-control） and vector （pYrAd-GFP） only carrying GFP reported gene were constructed as control. The rat VSMCs were cultured. There were two large groups of A （SOCS3 up-regulated）： control group, IL-6/IFN-γ group, IL-6/IFN-γ＋pYrAd-rSOCS3 group, IL-6/IFN-γ＋pYrAd-GFP group; and B （SOCS3 down-regulated）： control group, IL-6/IFN-γ group, IL-6/IFN-γ＋SiRNA-rSOCS3 group and IL-6/IFN -T＋SiRNA-control group. The pYrAd-rSOCS3 and SiRNA-rSOCS3 were transfected into VSMCs in- duced by IL-6/IFN-γ. After 24 h, real-time reverse transcription polymerase chain reaction （RT-PCR） and Western blotting were used to detect the mRNA and protein expression of SOCS3, STAT3 （only by Western blotting）, P-STAT3 （only by Western blotting）, IL-1β, IL-6, TNF-α, MCP-1 and ICAM-1. The MTT, Transwell assay and flow cytometry were used to examine VSMCs proliferation, migration and cell cycle progression, respectively. As compared with control group, the mRNA and protein expression of SOCS3, STAT3, P-STAT3, IL-1β, IL-6, TNF-α, MCP-1 and ICAM-1 was significantly up-regulated in VSMCs stimulated by IL-6/IFN-γ. However, in VSMCs transfected with pYrAd-rSOCS3 before stimulation with IL-6/IFN-γ, the expression of SOCS3 mRNA and protein was further up-regulated, and that of STAT3, P-STAT3, IL-1β, IL-6, TNF-α, MCP-1 and ICAM-1 was significantly down-regulated as compared with IL-6/IFN-γ group and IL-6/IFN-γ＋pYrAd-GFP group. The expression of those re- lated-cytokines in IL-6/IFN-γ＋SiRNA-rSOCS3 group was markedly increased as compared with IL-6/IFN-γ group and IL-6/IFN-γ＋SiRNA-control group. The absorbance （A） values, the number of cells migrating to the lower chamber, and percentage of cells in the G2/M＋S phase were increased in VSMCs stimulated by IL-6/IFN-γ. In VSMCs incubated with pYrAd-rSOCS3 or SiRNA-rSOCS3 be- fore IL-6/IFN-γ stimulation, the A values, the number of cells migrating to the lower chamber, and the percentage of cells in the G2/M＋S phase were significantly decreased, and increased respectively. These results imply that IL-6/IFN-γ, strong inflammatory stimulators, can promote transformation of VSMCs phenotype form a quiescent contractile state to a synthetic state by activating JAK2/STAT3 pathway. Over-expresssed SOCS3 might inhibit pro-inflammatory effect, migration and growth of VSMCs by blocking STAT3 activation and phosphorylation. These data in vitro confirm that SOCS3 may play a negatively regulatory role in development and progression of vein graft failure. These conclusions can provide a novel strategy for clinical treatment of vein graft diseases and a new theoretic clue for related drug development.
