BACKGROUND: The increased β-arrestin-2 and its combination with G-protein-coupled receptors (GPCRs) lead to GPCRs desensitization. The latter may be responsible for decreased contractile reactivity in the mesenteric ...BACKGROUND: The increased β-arrestin-2 and its combination with G-protein-coupled receptors (GPCRs) lead to GPCRs desensitization. The latter may be responsible for decreased contractile reactivity in the mesenteric arteries of cirrhotic patients and rats. The present study is to investigate the machinery changes of α-adrenergic receptors and G proteins and their roles in the contractility of mesenteric arteries of cirrhotic patients and animal models. METHODS: Patients with cirrhosis due to hepatitis B and cirrhotic rats induced by CCl 4 were studied. Mesenteric artery contractility in response to norepinephrine was determined by a vessel perfusion system. The contractile effect of G protein-coupled receptor kinase-2 (GRK-2) inhibitor on the mesenteric artery was evaluated. The protein expression of the α 1 adrenergic receptor, G proteins, β-arrestin-2, GRK-2 as well as the activity of Rho associated coiled-coil forming protein kinase-1 (ROCK-1) were measured by Western blot. In addition, the interaction of α 1 adrenergic receptor with β-arrestin-2 was assessed by co-immunoprecipitation. RESULTS: The portal vein pressure of cirrhotic patients and rats was significantly higher than that of controls. The doseresponse curve to norepinephrine in mesenteric arteriole was shifted to the right, and EC 50 was significantly increased in cirrhotic patients and rats. There were no significant differences in the expressions of the α 1 adrenergic receptor and G proteins in the cirrhotic group compared with the controls. However, the protein expressions of GRK-2 and β-arrestin-2 were significantly elevated in cirrhotic patients and rats compared with those of the controls. The interaction of the α 1 adrenergic receptor and β-arrestin-2 was significantly aggravated. This interaction was significantly reversed by GRK-2 inhibitor. Both the protein expression and activity of ROCK-1 were significantly decreased in the mesenteric artery in patients with cirrhosis compared with those of the controls, and this phenomenon was not shown in the cirrhotic rats. Norepinephrine significantly increased the activity of ROCK-1 in normal rats but not in cirrhotic ones. Norepinephrine significantly increased ROCK-1 activity in cirrhotic rats when GRK-2 inhibitor was used. CONCLUSIONS: β-arrestin-2 expression and its interaction with GPCRs are significantly upregulated in the mesenteric arteries in patients and rats with cirrhosis. These upregulations result in GPCR desensitization, G-protein dysfunction and ROCK inhibition. These may explain the decreased contractility of the mesenteric artery in response to vasoconstrictors.展开更多
Rho相关的卷曲蛋白激酶(Rho-associated coiled-coil protein kinase,ROCK)是新近发现的与细胞凋亡相关的激酶,在多种细胞中均有表达,ROCK参与调节细胞的多种行为与功能,包括收缩、游走黏附、增殖及调亡。研究表明ROCK与血管再狭窄、心...Rho相关的卷曲蛋白激酶(Rho-associated coiled-coil protein kinase,ROCK)是新近发现的与细胞凋亡相关的激酶,在多种细胞中均有表达,ROCK参与调节细胞的多种行为与功能,包括收缩、游走黏附、增殖及调亡。研究表明ROCK与血管再狭窄、心肌损伤、心肌细胞凋亡及心力衰竭等有关联。展开更多
目的:观察Rho激酶抑制剂法舒地尔(Fasudil)对人高侵袭潜能HCC细胞株3(human high metastatic liver cancer cells 3,HCCLM3)侵袭转移的影响,并且探讨其作用的机制。方法:应用100 mol/L Fasudil作用于HCCLM3细胞,采用肌动蛋白微丝荧光染...目的:观察Rho激酶抑制剂法舒地尔(Fasudil)对人高侵袭潜能HCC细胞株3(human high metastatic liver cancer cells 3,HCCLM3)侵袭转移的影响,并且探讨其作用的机制。方法:应用100 mol/L Fasudil作用于HCCLM3细胞,采用肌动蛋白微丝荧光染色和侵袭小室实验观察HCCLM3细胞的运动侵袭能力。HCCLM3细胞经过处理后分为阴性对照组、Fasudil作用组、BTBD7干扰组,通过Western印迹检测BTB/POZ结构域蛋白7(BR-C,ttk and bab/pox virus domain containing 7,BTBD7)、Ras同系物家族成员C(ras homolog family member C,Rho C)、Rho关联卷曲螺旋蛋白激酶2(Rhoassociated,coiled-coil containing protein kinase 2,ROCK2)、MMP2和MMP9蛋白表达水平,酶谱分析法检测MMP2和MMP9活性水平。BTBD7干扰组作为阳性对照。结果:Fasudil处理后HCCLM3侵袭运动能力下降,BTBD7,Rho C,ROCK2蛋白表达下调,MMP2和MMP9活性降低,与阴性对照组比较差异有统计学意义(均P<0.01)。结论:Fasudil具有干预BTBD7-ROCK2信号通路、抑制HCC侵袭转移的重要作用。展开更多
目的研究Rho相关卷曲螺旋蛋白激酶1(ROCK1)在动脉粥样硬化血管壁中的表达及其与基质金属蛋白酶2(MMP2)、转化生长因子1(TGF-β1)的相关性。方法选择30只载脂蛋白E基因敲除小鼠为实验组,高脂饲料喂养,另选30只C57BL/6小鼠为对照组,普通...目的研究Rho相关卷曲螺旋蛋白激酶1(ROCK1)在动脉粥样硬化血管壁中的表达及其与基质金属蛋白酶2(MMP2)、转化生长因子1(TGF-β1)的相关性。方法选择30只载脂蛋白E基因敲除小鼠为实验组,高脂饲料喂养,另选30只C57BL/6小鼠为对照组,普通饲料喂养。在喂养的第10、16、22、28及34周,取眼球血监测小鼠血脂水平;取小鼠腹主动脉作为标本,包埋切片并进行苏木精-伊红染色观察血管壁形态;应用免疫组化染色观察血管壁中ROCK1、MMP2、TGF-β1的表达;使用Image Pro Plus 6.0软件测量切片中血管壁厚度、斑块面积、血管壁中ROCK1、MMP2及TGF-β1的表达量。采用SPSS 27.0统计软件进行数据分析。采用单因素方差分析进行组间比较,两两比较采用Tukey检验。采用Pearson相关与线性回归分析ROCK1与血管壁厚度及斑块面积、MMP2、TGF-β1的关系。结果成功建立动脉粥样硬化小鼠模型。在喂养第10、16、22、28及34周,实验组血脂水平明显高于对照组,差异有统计学意义(P<0.05)。自喂养第16周起,实验组小鼠血管内均有斑块形成,随着喂养时间的延长,斑块面积和血管壁厚度不断增加,差异有统计学意义(P<0.05);血管壁内ROCK1的表达逐步增高,其表达与斑块面积及血管壁厚度呈正相关(r=0.821,0.730;P<0.05)。线性相关分析及回归分析显示,ROCK1与MMP2、TGF-β1表达均呈正相关(r=0.801,0.906;P<0.05)。结论在动脉粥样硬化血管壁中存在ROCK1蛋白的表达,且表达量随着血管壁厚度增加而增高,ROCK1的表达与MMP2、TGF-β1呈显著正相关性。鉴于ROCK1蛋白的致血管痉挛作用,提示动脉粥样硬化血管壁可能易于痉挛,具体机制需进一步研究。展开更多
基金supported by a grant from the National Natural Science Foundation of China (30972920)
文摘BACKGROUND: The increased β-arrestin-2 and its combination with G-protein-coupled receptors (GPCRs) lead to GPCRs desensitization. The latter may be responsible for decreased contractile reactivity in the mesenteric arteries of cirrhotic patients and rats. The present study is to investigate the machinery changes of α-adrenergic receptors and G proteins and their roles in the contractility of mesenteric arteries of cirrhotic patients and animal models. METHODS: Patients with cirrhosis due to hepatitis B and cirrhotic rats induced by CCl 4 were studied. Mesenteric artery contractility in response to norepinephrine was determined by a vessel perfusion system. The contractile effect of G protein-coupled receptor kinase-2 (GRK-2) inhibitor on the mesenteric artery was evaluated. The protein expression of the α 1 adrenergic receptor, G proteins, β-arrestin-2, GRK-2 as well as the activity of Rho associated coiled-coil forming protein kinase-1 (ROCK-1) were measured by Western blot. In addition, the interaction of α 1 adrenergic receptor with β-arrestin-2 was assessed by co-immunoprecipitation. RESULTS: The portal vein pressure of cirrhotic patients and rats was significantly higher than that of controls. The doseresponse curve to norepinephrine in mesenteric arteriole was shifted to the right, and EC 50 was significantly increased in cirrhotic patients and rats. There were no significant differences in the expressions of the α 1 adrenergic receptor and G proteins in the cirrhotic group compared with the controls. However, the protein expressions of GRK-2 and β-arrestin-2 were significantly elevated in cirrhotic patients and rats compared with those of the controls. The interaction of the α 1 adrenergic receptor and β-arrestin-2 was significantly aggravated. This interaction was significantly reversed by GRK-2 inhibitor. Both the protein expression and activity of ROCK-1 were significantly decreased in the mesenteric artery in patients with cirrhosis compared with those of the controls, and this phenomenon was not shown in the cirrhotic rats. Norepinephrine significantly increased the activity of ROCK-1 in normal rats but not in cirrhotic ones. Norepinephrine significantly increased ROCK-1 activity in cirrhotic rats when GRK-2 inhibitor was used. CONCLUSIONS: β-arrestin-2 expression and its interaction with GPCRs are significantly upregulated in the mesenteric arteries in patients and rats with cirrhosis. These upregulations result in GPCR desensitization, G-protein dysfunction and ROCK inhibition. These may explain the decreased contractility of the mesenteric artery in response to vasoconstrictors.
文摘Rho相关的卷曲蛋白激酶(Rho-associated coiled-coil protein kinase,ROCK)是新近发现的与细胞凋亡相关的激酶,在多种细胞中均有表达,ROCK参与调节细胞的多种行为与功能,包括收缩、游走黏附、增殖及调亡。研究表明ROCK与血管再狭窄、心肌损伤、心肌细胞凋亡及心力衰竭等有关联。
文摘目的:观察Rho激酶抑制剂法舒地尔(Fasudil)对人高侵袭潜能HCC细胞株3(human high metastatic liver cancer cells 3,HCCLM3)侵袭转移的影响,并且探讨其作用的机制。方法:应用100 mol/L Fasudil作用于HCCLM3细胞,采用肌动蛋白微丝荧光染色和侵袭小室实验观察HCCLM3细胞的运动侵袭能力。HCCLM3细胞经过处理后分为阴性对照组、Fasudil作用组、BTBD7干扰组,通过Western印迹检测BTB/POZ结构域蛋白7(BR-C,ttk and bab/pox virus domain containing 7,BTBD7)、Ras同系物家族成员C(ras homolog family member C,Rho C)、Rho关联卷曲螺旋蛋白激酶2(Rhoassociated,coiled-coil containing protein kinase 2,ROCK2)、MMP2和MMP9蛋白表达水平,酶谱分析法检测MMP2和MMP9活性水平。BTBD7干扰组作为阳性对照。结果:Fasudil处理后HCCLM3侵袭运动能力下降,BTBD7,Rho C,ROCK2蛋白表达下调,MMP2和MMP9活性降低,与阴性对照组比较差异有统计学意义(均P<0.01)。结论:Fasudil具有干预BTBD7-ROCK2信号通路、抑制HCC侵袭转移的重要作用。
文摘目的研究Rho相关卷曲螺旋蛋白激酶1(ROCK1)在动脉粥样硬化血管壁中的表达及其与基质金属蛋白酶2(MMP2)、转化生长因子1(TGF-β1)的相关性。方法选择30只载脂蛋白E基因敲除小鼠为实验组,高脂饲料喂养,另选30只C57BL/6小鼠为对照组,普通饲料喂养。在喂养的第10、16、22、28及34周,取眼球血监测小鼠血脂水平;取小鼠腹主动脉作为标本,包埋切片并进行苏木精-伊红染色观察血管壁形态;应用免疫组化染色观察血管壁中ROCK1、MMP2、TGF-β1的表达;使用Image Pro Plus 6.0软件测量切片中血管壁厚度、斑块面积、血管壁中ROCK1、MMP2及TGF-β1的表达量。采用SPSS 27.0统计软件进行数据分析。采用单因素方差分析进行组间比较,两两比较采用Tukey检验。采用Pearson相关与线性回归分析ROCK1与血管壁厚度及斑块面积、MMP2、TGF-β1的关系。结果成功建立动脉粥样硬化小鼠模型。在喂养第10、16、22、28及34周,实验组血脂水平明显高于对照组,差异有统计学意义(P<0.05)。自喂养第16周起,实验组小鼠血管内均有斑块形成,随着喂养时间的延长,斑块面积和血管壁厚度不断增加,差异有统计学意义(P<0.05);血管壁内ROCK1的表达逐步增高,其表达与斑块面积及血管壁厚度呈正相关(r=0.821,0.730;P<0.05)。线性相关分析及回归分析显示,ROCK1与MMP2、TGF-β1表达均呈正相关(r=0.801,0.906;P<0.05)。结论在动脉粥样硬化血管壁中存在ROCK1蛋白的表达,且表达量随着血管壁厚度增加而增高,ROCK1的表达与MMP2、TGF-β1呈显著正相关性。鉴于ROCK1蛋白的致血管痉挛作用,提示动脉粥样硬化血管壁可能易于痉挛,具体机制需进一步研究。