Background Hyperglycemia may accelerate liver fibrosis.Currently,there is no effective treatment for liver fibrosis induced by type 2 diabetes.The study aim was to investigate whether RhoA/Rho kinase （ROCK） pathway ...Background Hyperglycemia may accelerate liver fibrosis.Currently,there is no effective treatment for liver fibrosis induced by type 2 diabetes.The study aim was to investigate whether RhoA/Rho kinase （ROCK） pathway is involved in liver fibrosis in the rats with type 2 diabetes and define the protective effects of fasudil on livers.Methods A rat model of type 2 diabetes was established by high fat diet combined with streptozotocin （30 mg/kg,intraperitoneal injection）.Animals were randomly assigned to 3 groups：control rats,untreated diabetic rats that received vehicle and fasudil-treated diabetic rats that received ROCK inhibitor fasudil hydrochloride hydrate （10 mg/kg per day,intraperitoneal injection,for 14 weeks）.The morphological features of liver were observed by HE staining.Accumulation of collagen in livers was determined by Masson staining and the measurement of hydroxyproline.The mRNA expression of transforming growth factor-β1 （TGFβ1）,connective tissue growth factor （CTGF）,type-Ⅰ,and type-Ⅲ procollagen was assessed with real-time polymerase chain reaction.The phosphorylation of myosin phosphatase target subunit-1 （MYPT1）and the protein levels of TGFβ1 and α-smooth muscle actin （α-SMA） were evaluated by Western blotting.Results Compared with control rats,untreated diabetic rats showed higher values of collagen and hydroxyproline in livers （P ＜0.01）,the phosphorylation of MYPT1 and the protein levels of TGFβ1 and α-SMA were increased （P ＜0.01）,and the mRNA expression of TGFβ1,CTGF,type-Ⅰ,and type-Ⅲ procollagen was upregulated （P ＜0.01）; compared with untreated diabetic rats,treatment with fasudil signifcantly reduced values of collagen and hydroxyproline （P ＜0.01）,and decreased the phosphorylation of MYPT1 and the levels of TGFβ1 and α-SMA （P ＜0.01）,concomitant with the downregulation of TGFβ1/CTGF,type-Ⅰ,and type-Ⅲ procollagen mRNA expression （P ＜0.01）.Conclusions Fasudil ameliorates liver fibrosis in rats with type 2 展开更多
Wnt/β-catenin regulates cellular functions related to tumor initiation and progression, cell proliferation, differ- entiation, survival, and adhesion, β-Catenin-independent Wnt pathways have been proposed to regulat...Wnt/β-catenin regulates cellular functions related to tumor initiation and progression, cell proliferation, differ- entiation, survival, and adhesion, β-Catenin-independent Wnt pathways have been proposed to regulate cell polarity and migration, including metastasis. In this review, we discuss the possible roles of both β-catenin-dependent and -independent signaling pathways in tumor progression, with an emphasis on their regulation of Rho-family GTPases, cytoskeletal remodeling, and relationships with cell-cell adhesion and cilia/ciliogenesis.展开更多
Background Hypoxic pulmonary hypertension （HPH） contributes to the pathogenesis of cardiopulmonary diseases.Several lines of evidence indicate that the Rho A/Rho-kinase pathway play an important role in the progress...Background Hypoxic pulmonary hypertension （HPH） contributes to the pathogenesis of cardiopulmonary diseases.Several lines of evidence indicate that the Rho A/Rho-kinase pathway play an important role in the progress of pulmonary hypertension.Stains have been shown exert numerous biological effects that are independent of their cholesterollowering property.We hypothesized that the Rho A/Rho-kinase pathway is involved in the pathogenesis of HPH,and that atorvastatin would attenuate involvement of the Rho A/Rho-kinase pathway in a HPH rat model.Methods Thirty-two Wistar rats were randomly divided into four groups：control group,hypoxic group,atovastatin group,and normal saline group.The control group was kept in a normoxia environment.The other groups were exposed to hypoxia for three weeks.Atovastatin was administered daily via a gastric gavage in the atovastatin group.We measured the mean pulmonary arterial pressure （mPAP）,the ratio of the right ventricular weight to the sum of the weights of the left heart ventricle and septum （RV/（LV＋S））,arteriole wall thickness/vascular external diameter （WT％）,vascular area/total vascular area （WA％）,expression of RhoA and phos-MYPT-1 protein in lung tissue,and NF-κB activation in pulmonary vascular smooth muscle cells.Results Compared with the control group,mPAP,RV/（LV＋S）,WT％,WA％,NF-κB activation,expression of RhoA,and phos-MYPT-1 were increased in the hypoxic and normal saline groups （P ＜0.05）.Compared with the hypoxic group,mPAP,RV/（LV＋S）,WT％,WA％,NF-κB activation,expression of RhoA,and phos-MYPT-1 were decreased in the atovastatin group （P ＜0.05）.Correlations between phos-MPTY-1 and mPAP,WA％,WT％,and NF-κB activation were all positive.Conclusions The Rho NRho-kinase pathway plays an important role in the development of HPH.Atorvastatin reversed HPH by inhibiting the activity of Rho A/Rho-kinase and NF-κB.展开更多
A spinal cord injury refers to an injury to the spinal cord that is caused by a trauma instead of diseases. Spinal cord injury includes a primary mechanical injury and a much more complex secondary injury process invo...A spinal cord injury refers to an injury to the spinal cord that is caused by a trauma instead of diseases. Spinal cord injury includes a primary mechanical injury and a much more complex secondary injury process involving inflammation, oxidation, excitotoxicity, and cell death. During the secondary injury, many signal pathways are activated and play important roles in mediating the pathogenesis of spinal cord injury. Among them, the Rho A/Rho kinase pathway plays a particular role in mediating spinal degeneration and regeneration. In this review, we will discuss the role and mechanism of Rho A/Rho kinase-mediated spinal cord pathogenesis, as well as the potential of targeting Rho A/Rho kinase as a strategy for promoting both neuroprotection and axonal regeneration.展开更多
Previous studies have shown that the neurite growth inhibitor Nogo-A can cause secondary neural damage by activating Rho A. In the present study, we hypothesized that electroacupuncture promotes neurological functiona...Previous studies have shown that the neurite growth inhibitor Nogo-A can cause secondary neural damage by activating Rho A. In the present study, we hypothesized that electroacupuncture promotes neurological functional recovery after spinal cord injury by inhibiting Rho A expression. We established a rat model of acute spinal cord injury using a modification of Allen＇s method. The rats were given electroacupuncture treatment at Dazhui（Du14）, Mingmen（Du4）, Sanyinjiao（SP6）, Huantiao（GB30）, Zusanli（ST36） and Kunlun（BL60） acupoints with a sparsedense wave at a frequency of 4 Hz for 30 minutes, once a day, for a total of 7 days. Seven days after injury, the Basso, Beattie and Bresnahan（BBB） locomotor scale and inclined plane test scores were significantly increased, the number of apoptotic cells in the spinal cord tissue was significantly reduced, and Rho A and Nogo-A m RNA and protein expression levels were decreased in rats given electroacupuncture compared with rats not given electroacupuncture. Four weeks after injury, pathological tissue damage in the spinal cord at the site of injury was alleviated, the numbers of glial fibrillary acidic protein- and neurofilament 200-positive fibers were increased, the latencies of somatosensory-evoked and motor-evoked potentials were shortened, and their amplitudes were increased in rats given electroacupuncture. These findings suggest that electroacupuncture treatment reduces neuronal apoptosis and decreases Rho A and Nogo-A m RNA and protein expression at the site of spinal cord injury, thereby promoting tissue repair and neurological functional recovery.展开更多
Maintenance of cell junctions plays a crucial role in the regulation of cellular functions including cell proliferation, permeability, and cell death. Disruption of cell junctions is implicated in a variety of human d...Maintenance of cell junctions plays a crucial role in the regulation of cellular functions including cell proliferation, permeability, and cell death. Disruption of cell junctions is implicated in a variety of human disorders, such as inflammatory diseases and cancers. Understanding molecular regulation of cell junctions is important for development of therapeutic strategies for intervention of human diseases. Ubiquitination is an important type of post-translational modification that primarily regulates endogenous protein stability, recep- tor internalization, enzyme activity, and protein-protein interactions. Ubiquitination is tightly regulated by ubiq- uitin E3 ligases and can be reversed by deubiquitinating enzymes. Recent studies have been focusing on inves- tigating the effect of protein stability in the regulation of cell-cell junctions. Ubiquitination and degradation of cadherins, claudins, and their interacting proteins are implicated in epithelial and endothelial barrier disruption. Recent studies have revealed that ubiquitination is involved in regulation of Rho GTPases＇ biological activities. Taken together these studies, ubiquitination plays a critical role in modulating cell junctions and motility. In this review, we will discuss the effects of ubiquitination and deubiquitination on protein stability and expression of key proteins in the cell-cell junctions, including junction proteins, their interacting proteins, and small Rho GTPases. We provide an overview of protein stability in modulation of epithelial and endothelial barrier integrity and introduce potential future search directions to better understand the effects of ubiquitination on human disorders caused by dysfunction of cell junctions.展开更多
文摘Background Hyperglycemia may accelerate liver fibrosis.Currently,there is no effective treatment for liver fibrosis induced by type 2 diabetes.The study aim was to investigate whether RhoA/Rho kinase （ROCK） pathway is involved in liver fibrosis in the rats with type 2 diabetes and define the protective effects of fasudil on livers.Methods A rat model of type 2 diabetes was established by high fat diet combined with streptozotocin （30 mg/kg,intraperitoneal injection）.Animals were randomly assigned to 3 groups：control rats,untreated diabetic rats that received vehicle and fasudil-treated diabetic rats that received ROCK inhibitor fasudil hydrochloride hydrate （10 mg/kg per day,intraperitoneal injection,for 14 weeks）.The morphological features of liver were observed by HE staining.Accumulation of collagen in livers was determined by Masson staining and the measurement of hydroxyproline.The mRNA expression of transforming growth factor-β1 （TGFβ1）,connective tissue growth factor （CTGF）,type-Ⅰ,and type-Ⅲ procollagen was assessed with real-time polymerase chain reaction.The phosphorylation of myosin phosphatase target subunit-1 （MYPT1）and the protein levels of TGFβ1 and α-smooth muscle actin （α-SMA） were evaluated by Western blotting.Results Compared with control rats,untreated diabetic rats showed higher values of collagen and hydroxyproline in livers （P ＜0.01）,the phosphorylation of MYPT1 and the protein levels of TGFβ1 and α-SMA were increased （P ＜0.01）,and the mRNA expression of TGFβ1,CTGF,type-Ⅰ,and type-Ⅲ procollagen was upregulated （P ＜0.01）; compared with untreated diabetic rats,treatment with fasudil signifcantly reduced values of collagen and hydroxyproline （P ＜0.01）,and decreased the phosphorylation of MYPT1 and the levels of TGFβ1 and α-SMA （P ＜0.01）,concomitant with the downregulation of TGFβ1/CTGF,type-Ⅰ,and type-Ⅲ procollagen mRNA expression （P ＜0.01）.Conclusions Fasudil ameliorates liver fibrosis in rats with type 2
文摘Wnt/β-catenin regulates cellular functions related to tumor initiation and progression, cell proliferation, differ- entiation, survival, and adhesion, β-Catenin-independent Wnt pathways have been proposed to regulate cell polarity and migration, including metastasis. In this review, we discuss the possible roles of both β-catenin-dependent and -independent signaling pathways in tumor progression, with an emphasis on their regulation of Rho-family GTPases, cytoskeletal remodeling, and relationships with cell-cell adhesion and cilia/ciliogenesis.
文摘Background Hypoxic pulmonary hypertension （HPH） contributes to the pathogenesis of cardiopulmonary diseases.Several lines of evidence indicate that the Rho A/Rho-kinase pathway play an important role in the progress of pulmonary hypertension.Stains have been shown exert numerous biological effects that are independent of their cholesterollowering property.We hypothesized that the Rho A/Rho-kinase pathway is involved in the pathogenesis of HPH,and that atorvastatin would attenuate involvement of the Rho A/Rho-kinase pathway in a HPH rat model.Methods Thirty-two Wistar rats were randomly divided into four groups：control group,hypoxic group,atovastatin group,and normal saline group.The control group was kept in a normoxia environment.The other groups were exposed to hypoxia for three weeks.Atovastatin was administered daily via a gastric gavage in the atovastatin group.We measured the mean pulmonary arterial pressure （mPAP）,the ratio of the right ventricular weight to the sum of the weights of the left heart ventricle and septum （RV/（LV＋S））,arteriole wall thickness/vascular external diameter （WT％）,vascular area/total vascular area （WA％）,expression of RhoA and phos-MYPT-1 protein in lung tissue,and NF-κB activation in pulmonary vascular smooth muscle cells.Results Compared with the control group,mPAP,RV/（LV＋S）,WT％,WA％,NF-κB activation,expression of RhoA,and phos-MYPT-1 were increased in the hypoxic and normal saline groups （P ＜0.05）.Compared with the hypoxic group,mPAP,RV/（LV＋S）,WT％,WA％,NF-κB activation,expression of RhoA,and phos-MYPT-1 were decreased in the atovastatin group （P ＜0.05）.Correlations between phos-MPTY-1 and mPAP,WA％,WT％,and NF-κB activation were all positive.Conclusions The Rho NRho-kinase pathway plays an important role in the development of HPH.Atorvastatin reversed HPH by inhibiting the activity of Rho A/Rho-kinase and NF-κB.
文摘目的:通过固定循经取穴配伍以不同部位选穴进行对比研究,以糖尿病胃轻瘫(diabetic gastroparesis,DGP)大鼠为观察对象,研究不同按部选穴针刺治疗对DGP大鼠Rho A/ROCK信号的表达差异,探讨按部选穴是影响腧穴配伍效应的主要影响因素.方法:将60只♂SPF级SD大鼠,适应性喂养1 w k后,随机分为空白对照组、模型组、足三里+中脘组、足三里+内关组、足三里+非经非穴组,每组12只.除空白对照组12只外,其余48只大鼠运用链脲佐菌素腹腔注射造糖尿病模型,普通喂养8 wk后建立DGP大鼠模型,针刺治疗4 wk,于13 w k末墨汁灌胃后处死,取胃窦组织.运用Western blot检测胃窦平滑肌组织Ras同源物基因组成员A(Ras homolog gene family,member A,Rho A)、Rho蛋白相关卷曲螺旋激酶(Rho-associatedc,oiled-coil containing protein kinase,ROCK)、肌球蛋白磷酸酶靶亚单位1(myosin phosphatase target subunit 1,MYPT1)、p-MYPT1蛋白的表达量;应用免疫组织化学检测胃窦平滑肌组织Rho A蛋白平均灰度值改变.结果:与空白对照组相比,模型组的小肠推进率、胃窦平滑肌组织Rho A、ROCK、MYPT1、p-MYPT1蛋白的表达量明显降低(P<0.01),胃窦平滑肌组织R h o A灰度值表达升高(P<0.05).与模型组相比,足三里+中脘组、足三里+内关组、足三里+非经非穴组的小肠推进率和胃窦平滑肌组织Rho A、ROCK、MYPT1、p-MYPT1蛋白的表达量明显升高(P<0.05),胃窦平滑肌组织Rho A灰度值表达均具有降低的趋势(P<0.05).与足三里+中脘组相比,足三里+内关、足三里+非经非穴组胃窦平滑肌组织R h o A、ROCK、MYPT1、p-MYPT1蛋白的表达量降低(P<0.05),胃窦平滑肌组织Rho A灰度值表达升高(P<0.05).在治疗期间,与模型组相比,足三里+中脘组的饮食量明显降低(P<0.05).结论:针刺能通过上调Rho A/ROCK信号的表达来促进胃平滑肌收缩,改善DGP的症状;证实按部选穴是影响腧穴配伍效应的重要因素,且配伍局部穴明
基金supported by NIH NS050243,NS059622,NS073636,DOD CDMRP W81XWH-12-1-0562,DVA 1I01BX002356-01A1Craig H Neilsen Foundation#296749+2 种基金Wallace H.Coulter FoundationIndiana Spinal Cord and Brain Injury Research FoundationMari Hulman George Endowment Funds
文摘A spinal cord injury refers to an injury to the spinal cord that is caused by a trauma instead of diseases. Spinal cord injury includes a primary mechanical injury and a much more complex secondary injury process involving inflammation, oxidation, excitotoxicity, and cell death. During the secondary injury, many signal pathways are activated and play important roles in mediating the pathogenesis of spinal cord injury. Among them, the Rho A/Rho kinase pathway plays a particular role in mediating spinal degeneration and regeneration. In this review, we will discuss the role and mechanism of Rho A/Rho kinase-mediated spinal cord pathogenesis, as well as the potential of targeting Rho A/Rho kinase as a strategy for promoting both neuroprotection and axonal regeneration.
基金supported by a grant from the Science and Technology Development Program of Jilin Province of China,No.2011084
文摘Previous studies have shown that the neurite growth inhibitor Nogo-A can cause secondary neural damage by activating Rho A. In the present study, we hypothesized that electroacupuncture promotes neurological functional recovery after spinal cord injury by inhibiting Rho A expression. We established a rat model of acute spinal cord injury using a modification of Allen＇s method. The rats were given electroacupuncture treatment at Dazhui（Du14）, Mingmen（Du4）, Sanyinjiao（SP6）, Huantiao（GB30）, Zusanli（ST36） and Kunlun（BL60） acupoints with a sparsedense wave at a frequency of 4 Hz for 30 minutes, once a day, for a total of 7 days. Seven days after injury, the Basso, Beattie and Bresnahan（BBB） locomotor scale and inclined plane test scores were significantly increased, the number of apoptotic cells in the spinal cord tissue was significantly reduced, and Rho A and Nogo-A m RNA and protein expression levels were decreased in rats given electroacupuncture compared with rats not given electroacupuncture. Four weeks after injury, pathological tissue damage in the spinal cord at the site of injury was alleviated, the numbers of glial fibrillary acidic protein- and neurofilament 200-positive fibers were increased, the latencies of somatosensory-evoked and motor-evoked potentials were shortened, and their amplitudes were increased in rats given electroacupuncture. These findings suggest that electroacupuncture treatment reduces neuronal apoptosis and decreases Rho A and Nogo-A m RNA and protein expression at the site of spinal cord injury, thereby promoting tissue repair and neurological functional recovery.
文摘Maintenance of cell junctions plays a crucial role in the regulation of cellular functions including cell proliferation, permeability, and cell death. Disruption of cell junctions is implicated in a variety of human disorders, such as inflammatory diseases and cancers. Understanding molecular regulation of cell junctions is important for development of therapeutic strategies for intervention of human diseases. Ubiquitination is an important type of post-translational modification that primarily regulates endogenous protein stability, recep- tor internalization, enzyme activity, and protein-protein interactions. Ubiquitination is tightly regulated by ubiq- uitin E3 ligases and can be reversed by deubiquitinating enzymes. Recent studies have been focusing on inves- tigating the effect of protein stability in the regulation of cell-cell junctions. Ubiquitination and degradation of cadherins, claudins, and their interacting proteins are implicated in epithelial and endothelial barrier disruption. Recent studies have revealed that ubiquitination is involved in regulation of Rho GTPases＇ biological activities. Taken together these studies, ubiquitination plays a critical role in modulating cell junctions and motility. In this review, we will discuss the effects of ubiquitination and deubiquitination on protein stability and expression of key proteins in the cell-cell junctions, including junction proteins, their interacting proteins, and small Rho GTPases. We provide an overview of protein stability in modulation of epithelial and endothelial barrier integrity and introduce potential future search directions to better understand the effects of ubiquitination on human disorders caused by dysfunction of cell junctions.
