Rho/Rho激酶信号通路与冠心病

Rho/Rho激酶信号通路是体内普通存在的一条信号转导通路,它通过调节细胞内肌动蛋白骨架的聚合状态参与多种细胞功能,包括细胞收缩、迁移、黏附、增殖、凋亡及基因表达等。Rho/Rho激酶信号通路的异常激活在冠心病的发病机制和病理生理中发挥了重要作用,对此信号转导通路的研究可以为冠心病的预防和治疗提供新的靶点。现就Rho/Rho激酶信号通路的特征及其与冠心病的关系作一综述。     

Rho/Rho激酶信号通路与缺血性脑血管病

Rho/Rho激酶信号通路是体内普遍存在的一条信号通路,它通过调节细胞内肌动蛋白骨架的聚合状态而扮演着"分子开关"角色,参与多种细胞功能.Rho/Rho激酶信号通路在缺血性脑血管病的危险因素、发病机制和病理生理学过程中发挥着重要作用,抑制Rho/Rho激酶信号通路能够取得显著的神经保护作用.     

Rho/Rho激酶信号通路与缺氧性肺动脉高压

缺氧性肺动脉高压（hypoxic pulmonary hypertension，HPH）是一些先天性心血管疾病和慢性肺部疾病最常见的并发症，以肺血管收缩反应性增强和肺血管结构重构为特征，其发生机制尚未完全清楚。近年来研究表明，Rho/Rho激酶信号通路在急性缺氧性肺血管收缩和慢性缺氧引起的肺动脉高压和肺血管结构重构过程中发挥重要作用。     

Rho／Rho激酶信号通路与高血压

1985年，Rho作为Ras同源物首先被克隆出来，此后的研究发现Rho作为信号调节分子联系细胞表面受体与肌动蛋白细胞骨架的组建，在细胞代谢过程中发挥重要作用。近年来，一系列研究显示Rho／Rho激酶信号通路主要通过磷酸化抑制肌球蛋白轻链磷酸酶（myosin light chain phosphase，MLCP）的活性来增加肌球蛋白轻链（myosin light chain，MLC）的磷酸化水平，从而增强平滑肌的收缩力，在高血压的发生和发展中起着非常重要的作用。     

Rho/Rho激酶信号通路与糖尿病肾病

糖尿病肾病(DN)是糖尿病重要的微血管并发症之一,其发病机制是多种因素共同作用的结果.近年来发现Rho/Rho激酶(Rho/ROCK)信号通路与多种组织重构如血管、心肌、肾纤维化等相关.高糖能够刺激肾脏细胞内Rho/ROCK信号通路的激活,后者通过调控转录因子的DNA结合活性上调多种基因的表达,从而引起各种炎性反应及肾...     

Rho/Rho激酶与缺血性脑卒中

Rho／Rho激酶是具有信息传导和分子开关功能的信号多肽，多种病理因素可使中枢神经系统等组织内Rho激酶异常激活。在神经系统，异常激活的Rho／Rho激酶与血管痉挛、缺血性神经元损伤密切相关，通过多种途径参与缺血性脑卒中的病理过程。本研究阐述缺血性脑卒中发病过程中，Rho／Rho激酶可能作用机制及Rho激酶抑制剂在缺血性脑卒中的应用。     

Rho激酶信号通路与大鼠心肌细胞凋亡的关系

目的探讨Rho激酶信号通路在心肌梗死模型大鼠心肌细胞凋亡组织中的表达变化及对心肌细胞凋亡的影响作用。方法选取健康雄性Wistar大鼠,通过结扎左前降支建立大鼠心肌梗死模型,将24 h后仍然存活的大鼠选取30只,随机分为模型组和治疗组(法舒地尔5 mg/kg,2次/d)各15只,并另外选取健康雄性大鼠15只作为假手术组,假手术组和模型组给予等量生理盐水处理,比较4 w后3组心肌梗死面积及Rho激酶mRNA、蛋白等指标的表达差异。结果 3组左心室收缩压(LVSP)、左室舒张压(LVEDP)、左室内压最大上升速率(+dp/dtmax)、左室内压最大下降速率(-dp/dtmax)差异均有统计学意义(P0.05),模型组LVSP、+dp/dtmax、-dp/dtmax显著低于治疗组和假手术组(P0.05),LVEDP显著高于治疗组和假手术组(P0.05),治疗组LVSP、+dp/dtmax、-dp/dtmax显著低于假手术组(P0.05),LVEDP显著高于假手术组(P0.05)。治疗组心肌缺血面积低于模型组但差异不显著(P0.05);治疗组心梗面积显著低于模型组(P0.05)。3组Rho激酶mRNA、Bax蛋白、Bcl-2蛋白表达差异有统计学意义(P0.05);组间差异均有统计学意义(P0.05)。结论心肌梗死大鼠心肌组织中的Rho激酶mRNA、Bax蛋白达显著增加,同时Bcl-2蛋白表达降低,法舒地尔能够降低Rho激酶mRNA表达,减少心肌细胞凋亡,减轻心肌梗死面积。     

Rho/Rho激酶系统在脑血管病中的作用

近年来,Rho/Rho-激酶系统在血管病发病机制中的作用逐渐被人们所认识。它通过多种途径导致蛛网膜下腔出血后血管痉挛、动脉粥样硬化和高血压的形成,加重缺血性卒中的神经功能损伤,还参与血管炎性反应和血管成形术后的再狭窄,并且是其形成和发展的重要环节。选择性Rho激酶抑制剂对这些脑血管病的预防和治疗作用已在许多动物和临床试验中被证实,其临床应用前景广阔。     

Rho/Rho激酶及其抑制剂的临床应用

问:最近为什么会对Rho/Rho激酶(ROCK)感兴趣? 答:原因有4: 1)ROCK在血管细胞收缩、纤维形成、局部黏附、细胞移动、细胞肥厚上起重要作用,引起许多心血管病变,如高血压、动脉粥样硬化等;     

抑制Rho/Rho激酶信号对动脉粥样硬化大鼠心血管系统的保护作用

目的探讨抑制Rho/Rho激酶信号对动脉粥样硬化(AS)过程中心血管系统的保护作用。方法实验设置对照组、模型组、Y-27632低剂量组、Y-27632高剂量组,采用高脂饮食配合钙超载的方法建立大鼠AS模型,并给予Y-27632抑制Rho/Rho激酶信号通路。末次给药后颈动脉取血检测血清TC、HDL,HE染色检测心肌组织病理改变,Western blot法检测肌球蛋白磷酸酶抗体(MYPT-1)磷酸化情况,RT-PCR检测内皮型一氧化氮合酶(eNOS)、I型纤溶酶原激活物抑制物(PAI-1)的表达。结果模型组大鼠血清HDL含量降低(P<0.05),TC、AS指数升高(P均<0.05),心肌松散、细胞排列紊乱;与模型组相比,Y-27632低、高剂量组TC含量以及AS指数降低(P均<0.05),心肌组织状态得到明显恢复;模型组MYPT-1磷酸化水平以及PAI-1 mRNA的表达升高(P均<0.05),而与模型组相比Y-27632低、高剂量组显著降低(P均<0.05);模型组eNOS mRNA表达显著降低(P<0.05),与模型组相比Y-27632低、高剂量组显著升高(P均<0.05)。结论采用Y-27632抑制Rho/Rho激酶信号通路,能够减缓AS进程从而保护心血管系统。     

NADPH氧化酶与Rho/Rho-激酶激活在外膜介导的血管重塑中的作用

目的　探讨NADPH氧化酶与Rho/Rho 激酶在外膜介导的血管重塑中的作用。方法在体去除兔颈动脉外膜 ,于术后即刻、1周及 2周取出颈动脉。用图像分析系统测定内膜及中层面积 ;应用多道生理仪测血管反应性 ;原位杂交及RT PCR检测mRNA表达。结果　 (1)血管外膜去除后内膜增生 ,2周时内膜增生较 1周时更为明显。对照侧无内膜增生。 (2 )与对照侧比较 ,去外膜侧血管在术后即刻、1周对去甲肾上腺素的收缩反应减弱 (P <0 0 5)。 (3 )与对照侧比较 ,去外膜侧NADPH氧化酶P2 2PhoxmRNA表达在 1周时增高 (P <0 0 5)。 (4)与对照侧比较 ,去外膜侧Rho 激酶mRNA表达在 2周时增高 (P <0 0 5)。结论　外膜去除后血管内膜增生 ,血管舒缩功能改变 ,其发生机制与NADPH氧化酶及Rho 激酶激活有关     

Rho/Rho激酶信号通路与糖尿病肾病

糖尿病肾病(DN)是糖尿病重要的微血管并发症之一,其发病机制是多种因素共同作用的结果.近年来发现Rho/Rho激酶(Rho/ROCK)信号通路与多种组织重构如血管、心肌、肾纤维化等相关.高糖能够刺激肾脏细胞内Rho/ROCK信号通路的激活,后者通过调控转录因子的DNA结合活性上调多种基因的表达,从而引起各种炎性反应及肾小球纤维化,而应用此信号通路选择性抑制剂后可明显改善DN的发生和发展,从而认为Rho/ROCK信号转导通路可能在DN的发病机制中起关键作用.     

Rho/Rho kinase is a key enzyme system involved in the angiotensin II signaling pathway of liver fibrosis and steatosis

BACKGROUND AND AIM: The molecular mechanisms underlying the involvement of the renin-angiotensin system in hepatic fibrosis are unclear. Recently, it was reported that a Rho kinase inhibitor prevented fibrosis of various tissues and that the Rho/Rho kinase pathway was involved in the renin-angiotensin system of vascular smooth muscle cells. In this study, the involvement of the Rho/Rho kinase pathway on angiotensin II signaling in liver fibrogenesis and generation of steatosis was investigated. METHODS: Rats were fed a choline-deficient/L-amino acid-defined (CDAA) diet continuously and treated with a Rho kinase inhibitor, Y-27632, and an angiotensin II receptor blocker, TCV-116. Liver histology and hepatic stellate cell activation were analyzed. Free radical production was detected by 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine immunostaining and the expression of tumor necrosis factor-alpha was examined. Isolated hepatic stellate cells were pretreated with a Rho kinase inhibitor, Y-27632, or an angiotensin II receptor blocker, CV-11974, and stimulated with angiotensin II, and mRNA expression of transforming growth factor-beta and alpha-smooth muscle actin was analyzed. RESULTS: Both the angiotensin II receptor blocker and the Rho kinase inhibitor improved fibrosis and steatosis of the liver in CDAA-fed rats. The increase in the number of hepatocytes positive for 4-hydroxynonenal and 8-hydroxy-2'-deoxyguanosine in CDAA-fed rats was significantly prevented by the angiotensin II receptor blocker and the Rho kinase inhibitor. The levels of tumor necrosis factor-alpha mRNA in the liver of CDAA-fed rats were significantly increased and this increase was significantly inhibited by treatment with the angiotensin II receptor blocker and the Rho kinase inhibitor. mRNA expression of transforming growth factor-beta and alpha-smooth muscle actin stimulated by angiotensin II was also significantly suppressed by these two drugs. CONCLUSION: These results suggest that the Rho/Rho kinase pathway is at least partly involved in the renin-angiotensin system and plays an important role in hepatic fibrosis and steatosis.     

小G蛋白Rho与肾间质纤维化

肾间质纤维化是所有慢性进行性肾脏疾病进展到终末期肾衰竭的共同形态学特点。Rho蛋白作为重要的细胞内信号分子,调节细胞的多种行为和功能,包括细胞生长,细胞骨架的重组,细胞移行和增殖等。近年研究发现,Rho蛋白及相关信号通路在肾间质纤维化过程中起着重要作用。通过作用于该通路从而达到治疗或逆转肾功能进行性损害的目的,可成为一个新的研究方向。     

辛伐他汀对野百合碱诱导肺动脉高压大鼠Rho／Rock的影响

目的观察辛伐他汀在野百合碱（MCT）诱导的肺动脉高压（PAH）大鼠模型中对Rh0／Rock表达的影响,探讨辛伐他汀改善MCT所致PAH的机制。方法雄性SD大鼠30只随机均分为对照组、MCT模型组和辛伐他汀干预组（SS组）。测量各组大鼠干预后平均肺动脉压力（mPAP）、右心室肥厚指数（RVHI）;观测大体的组织形态病理改变,采用免疫组化和Westernblot检测肺组织中的PCNA、α-SMA、Rho／Rock的表达。结果与对照组及干预组相比,MCT组的mPAP及RVHI显著增加（P〈0．05）,PCNA、α—SMA、Rho／Rock的表达显著增多（P〈0．05）;与对照组相比,SS组的mPAP及RVHI差异无统计学意义（P〉0．05）;而PCNA、α—SMA、Rho／Rock的表达显著增多（P〈0．05）。结论辛伐他汀可有效减轻MCT诱导的PAH大鼠肺动脉压力,其机翩可能与辛伐他汀通过Rho／Rock信号通路改善肺动脉平滑肌增生重构有关。     

高糖通过Rho/ROCK信号通路诱导人肾小球系膜细胞的炎症反应及纤维化

目的 探讨Rho/ROCK信号通路在高糖诱导的人肾小球系膜细胞(HMCs)炎症反应及纤维化中的作用.方法 将传代培养的HMCs同步化后分组:(1)正常糖浓度对照组(NG,5.5 mmol/L葡萄糖);(2)高糖组(HG,30 mmol/L葡萄糖);(3)甘露醇渗透压对照组(Man,5.5 mmol/L葡萄糖+24.5 mmol/L甘露醇);(4)NG+Y-27632(10 μmmol/L)组;(5)HG+Y-27632(10 μmmol/L)组,培养12、24、36、48、72 h后收集上清及细胞,用Western印迹检测RhoA蛋白的活化,用实时PCR检测细胞中RhoA、ROCK-Ⅰ、结缔组织生长因子(CTGF)、肿瘤坏死因子α(TNF-α)mRNA浓度的变化,用ELISA方法检测上清中纤维连接蛋白(FN)、CTGF、TNF-α的蛋白含量.结果 (1)高糖刺激HMCs的RhoA活化,于30 min即可出现活性升高,1 h达到高峰,之后活化的RhoA表达逐渐下降(P=0.02).(2)高糖培养下的HMCsRhoA、ROCK-Ⅰ、CTGF、TNF-α mRNA的表达较NG组明显升高(P＜0.05),并有一定的时间依赖性,Man组与NG组相比差异无统计学意义(P＞0.05).(3)经Y-27632预处理后,在正常糖和高糖浓度培养24 h或48 h后,NG+Y-27632组和HG+Y-27632组与未处理组相比RhoA、ROCK-Ⅰ、CTGF、TNF-α mRNA的表达明显下降(P＜0.01).(4)高糖呈时间依赖方式增加HMCs的FN、CTGF、TNF-α分泌(P＜0.05).(5)经Y-27632预处理,继续培养12、24、36、48、72 h后NG组和HG组中FN、CTGF、TNF-α蛋白的分泌较处理前明显降低(P＜0.05).结论 高糖可通过Rho/ROCK信号通路介导HMCs的炎症反应和纤维化,抑制此通路可作为减缓糖尿病肾病发生发展的潜在靶点.

Abstract：

Objective To investigate the role of Rho/ROCK signaling pathway in the process of human mesangial cells (HMCs) inflammation and fibrosis induced by high glucose. Methods Synchronized HMCs were divided into following groups: ( 1 ) Normal glucose control group ( NG, 5.5 mmol/L glucose); ( 2 ) High glucose group ( HG, 30 mmol/L glucose); (3) Mannitol group( Man,5.5 mmol/L glucose+ 24.5 mmol/L mannitol); (4) NG +Y-27632 group( 10 μ mmol/L Y-27632 ); ( 5 ) HG Y-27632 group ( 10 μmmol/L Y-27632 ). The supernatant and cells were collected at 0,12,24,36,48, and 72 h. Western blot was used to detect the active RhoA and total RhoA,while RhoA, ROCK-Ⅰ, CTGF, and TNF-α mRNA expressions were determined with realtime PGR method in the cells, then ELISA method was used to check protein levels of FN, CTGF, and TNF-α in the supernatant. Results ( 1 ) RhoA activation was stimulated after treatment for with 30 mmol/L glucose, peaked at 1 h, and then decreased ( P = 0. 02). (2) RhoA, ROCK-Ⅰ, CTGF, and TNF-α mRNA expressions in HMC cultured under high glucose were higher than those in the normal group ( P ＜ 0.05 ), and there was certain time-dependence. Besides, there was no statistical significance between Man and NG groups( P＞0. 05 ). ( 3 ) After Y-27632 pretreatment and being cultured with normal glucose and high glucose for24 h or48 h, RhoA, ROCK-Ⅰ, CTGF, and TNF-α mRNA expressions were significantly decreased ( P＜0.01 ) as compared with groups without treatment. (4) High glucose increased FN, CTGF,and TNF-α protein secretion of HMC in a time-dependent manner( P＜0. 05 ). ( 5 ) After Y-27632 pretreatment and being cultured with normal and high glucose for 12,24,36,48,72 h, FN, CTGF, and TNF-α protein secretions were significantly reduced( P＜0.05 ). Conclusion Rho/ROCK signaling pathway may mediate inflammation and fibrosis induced by high glucose in HMCs, supporting a potential role for inhibitors of Rho/ROCK in the treatment of diabetic nephropathy.     

Inhibition of Rho-kinase attenuates hypoxia-induced angiogenesis in the pulmonary circulation

Pulmonary hypertension (PH) is a common complication of chronic hypoxic lung diseases, which increase morbidity and mortality. Hypoxic PH has previously been attributed to structural changes in the pulmonary vasculature including narrowing of the vascular lumen and loss of vessels, which produce a fixed increase in resistance. Using quantitative stereology, we now show that chronic hypoxia caused PH and remodeling of the blood vessel walls in rats but that this remodeling did not lead to structural narrowing of the vascular lumen. Sustained inhibition of the RhoA/Rho-kinase pathway throughout the period of hypoxic exposure attenuated PH and prevented remodeling in intra-acinar vessels without enlarging the structurally determined lumen diameter. In chronically hypoxic lungs, acute Rho kinase inhibition markedly decreased PVR but did not alter the alveolar to arterial oxygen gap. In addition to increased vascular resistance, chronic hypoxia induced Rho kinase-dependent capillary angiogenesis. Thus, hypoxic PH was not caused by fixed structural changes in the vasculature but by sustained vasoconstriction, which was largely Rho kinase dependent. Importantly, this vasoconstriction had no role in ventilation-perfusion matching and optimization of gas exchange. Rho kinase also mediated hypoxia-induced capillary angiogenesis, a previously unrecognized but potentially important adaptive response.     

Actin' up: herpesvirus interactions with Rho GTPase signaling

Herpesviruses constitute a very large and diverse family of DNA viruses, which can generally be subdivided in alpha-, beta- and gammaherpesvirus subfamilies. Increasing evidence indicates that many herpesviruses interact with cytoskeleton-regulating Rho GTPase signaling pathways during different phases of their replication cycle. Because of the large differences between herpesvirus subfamilies, the molecular mechanisms and specific consequences of individual herpesvirus interactions with Rho GTPase signaling may differ. However, some evolutionary distinct but similar general effects on Rho GTPase signaling and the cytoskeleton have also been reported. Examples of these include Rho GTPase-mediated nuclear translocation of virus during entry in a host cell and Rho GTPase-mediated viral cell-to-cell spread during later stages of infection. The current review gives an overview of both general and individual interactions of herpesviruses with Rho GTPase signaling.