BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its d...BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of DR.Receptor for activated C kinase 1(RACK1)activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to apoptosis.Therefore,we hypothesize that the activation of RACK1 under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of DR.AIM To investigate the role and associated underlying mechanisms of RACK1 in the development of early DR.METHODS In this study,Sprague-Dawley rats and adult RPE cell line-19(ARPE-19)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1 in mediating PKC-εin early DR.Furthermore,the impact of RACK1 on apoptosis and barrier function of RPE cells was also investigated in the former model.RESULTS Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1 and PKC-εproteins in RPE cells following a prolonged modeling.Similarly,ARPE-19 cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1 and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer permeability.However,silencing RACK1 significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier function.CONCLUSION RACK1 plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function.展开更多
Summary： Activated protein C （APC）, a natural anticoagulant, has been reported to exert direct vascu- loprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. ...Summary： Activated protein C （APC）, a natural anticoagulant, has been reported to exert direct vascu- loprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. This study was aimed to explore the neuroprotective effects and potential mechanisms of APC on the neurovascular unit of neonatal rats with intrauterine infection-induced white matter injury. In- traperitoneal injection of 300 ~tg/kg lipopolysaccharide （LPS） was administered consecutively to preg- nant Sprague-Dawley rats at embryonic days 19 and 20 to establish the rat model of intrauterine infec- tion-induced white matter injury. Control rats were injected with an equivalent amount of sterile saline on the same time. APC at the dosage of 0.2 mg/kg was intraperitoneally injected to neonatal rats imme- diately after birth. Brain tissues were collected at postnatal day 7 and stained with hematoxylin and eo- sin （H＆E）. Immunohistochemistry was used to evaluate myelin basic protein （MBP） expression in the periventricular white matter region. Blood-brain barrier （BBB） permeability and brain water content ~were measured using Evens Blue dye and wet/dry weight method. Double immunofluorescence staining and real-time quantitative PCR were performed to detect microglial activation and the expression of protease activated receptor 1 （PAR1）. Typical pathological changes of white matter injury were ob- served in rat brains exposed to LPS, and MBP expression in the periventricular region was significantly decreased. BBB was disrupted and the brain water content was increased. Microglia were largely acti- vated and the mRNA and protein levels of PAR1 were elevated. APC administration ameliorated the pathological lesions of the white matter and increased MBP expression. BBB permeability and brain water content were reduced. Microglia activation was inhibited and the PAR1 mRNA and protein ex- pression levels were both down-regulated. Our results suggested that APC exerted neuroprotective ef- fects on multiple components of the neurovascular unit in neonatal rats with intrauterine infec- tion-induced white matter injury, and the underlying mechanisms might involve decreased expression of PAR1.展开更多
目的检测活化的蛋白激酶C受体1(RACK1)、低氧诱导因子1α(HIF-1α)、血管内皮生长因子(VEGF)在宫颈癌组织中的表达并探讨其病理学意义。方法选取2014年6月至2018年6月于本院行手术切除并经病理确诊的85例宫颈癌组织样本及其对应的癌旁组...目的检测活化的蛋白激酶C受体1(RACK1)、低氧诱导因子1α(HIF-1α)、血管内皮生长因子(VEGF)在宫颈癌组织中的表达并探讨其病理学意义。方法选取2014年6月至2018年6月于本院行手术切除并经病理确诊的85例宫颈癌组织样本及其对应的癌旁组织,通过免疫组织化学染色ABC法分别检测RACK1、HIF-1α、VEGF蛋白在宫颈癌组织及其癌旁组织中的表达。结合患者的临床病理资料,分析宫颈癌组织中RACK1、HIF-1α和VEGF蛋白表达与患者年龄及肿瘤直径、浸润深度、病理分级、淋巴结转移之间的关系,并分析三者表达之间的相关性。结果RACK1、HIF-1α、VEGF蛋白在宫颈癌组织中的表达均高于癌旁组织(P均<0.05),阳性表达率分别为81.2%(69/85)、63.5%(54/85)、89.4%(76/85)。RACK1表达与肿瘤浸润深度、病理分级和淋巴结是否转移有关(P均<0.05),HIF-1α和VEGF表达均与肿瘤直径、浸润深度、病理分级及淋巴结是否转移有关(P均<0.05)。RACK1、HIF-1α、VEGF蛋白的表达两两之间呈正相关(RACK1 vs HIF-1α:r=0.523,P=0.0439;RACK1 vs VEGF:r=0.428,P=0.0337;HIF-1αvs VEGF:r=0.689,P=0.0245)。结论RACK1、HIF-1、VEGF蛋白在宫颈癌组织中高表达且三者之间的表达呈正相关,提示其可能在肿瘤的发生、发展过程中起协同作用,可作为判断肿瘤侵袭、转移及预后的重要指标。展开更多
目的以GEO(Gene Expression Omnibus)数据库为基础分析活化的蛋白激酶C受体1(receptor for activated C kinase1,RACK1)在糖尿病肾小管病中的表达及可能的机制。方法通过搜索Nephroseq数据库及KEGG(Kyoto Encyclopedia of Genes and Gen...目的以GEO(Gene Expression Omnibus)数据库为基础分析活化的蛋白激酶C受体1(receptor for activated C kinase1,RACK1)在糖尿病肾小管病中的表达及可能的机制。方法通过搜索Nephroseq数据库及KEGG(Kyoto Encyclopedia of Genes and Genomes),明确RACK1在人的糖尿病肾小管病中表达情况及可能的通路。将培养的肾小管上皮细胞分为对照组、甘露醇组和高糖组,实时定量PCR测定其下游靶基因STAT1和STAT3的变化。FVB/N小鼠分为对照组和糖尿病肾病组,糖尿病肾病组小鼠给予腹腔注射链脲佐菌素构建糖尿病肾病的模型,实时定量PCR测定STAT1和STAT3 mRNA水平,免疫荧光染色明确p-STAT1和p-STAT3的表达情况。结果数据库数据分析发现RACK1在人糖尿病肾小管中表达明显升高。KEGG提示RACK1可能通过激活Jak-STAT信号通路发挥作用。与对照组比较,高糖组肾小管上皮细胞的RACK1、STAT1及STAT3的mRNA水平均明显升高,差异有统计学意义(P<0.05)。糖尿病肾病动物模型中,肾小管的RACK1、STAT1及STAT3的mRNA水平均明显升高,差异有统计学意义(P<0.05);免疫荧光示p-STAT1阳性,主要位于肾小管上皮细胞中。结论 RACK1在糖尿病肾小管中高表达,可能是通过磷酸化STAT1激活Jak-STAT信号通路参与糖尿病肾小管病的发生发展。展开更多
基金Supported by National Natural Science Foundation of China,No.82260211Key Research and Development Project in Jiangxi Province,No.20203BBG73058Chinese Medicine Science and Technology Project in Jiangxi Province,No.2020A0166.
文摘BACKGROUND Diabetic retinopathy(DR)is a major ocular complication of diabetes mellitus,leading to visual impairment.Retinal pigment epithelium(RPE)injury is a key component of the outer blood retinal barrier,and its damage is an important indicator of DR.Receptor for activated C kinase 1(RACK1)activates protein kinase C-ε(PKC-ε)to promote the generation of reactive oxygen species(ROS)in RPE cells,leading to apoptosis.Therefore,we hypothesize that the activation of RACK1 under hypoxic/high-glucose conditions may promote RPE cell apoptosis by modulating PKC-ε/ROS,thereby disrupting the barrier effect of the outer blood retinal barrier and contributing to the progression of DR.AIM To investigate the role and associated underlying mechanisms of RACK1 in the development of early DR.METHODS In this study,Sprague-Dawley rats and adult RPE cell line-19(ARPE-19)cells were used as in vivo and in vitro models,respectively,to explore the role of RACK1 in mediating PKC-εin early DR.Furthermore,the impact of RACK1 on apoptosis and barrier function of RPE cells was also investigated in the former model.RESULTS Streptozotocin-induced diabetic rats showed increased apoptosis and upregulated expression of RACK1 and PKC-εproteins in RPE cells following a prolonged modeling.Similarly,ARPE-19 cells exposed to high glucose and hypoxia displayed elevated mRNA and protein levels of RACK1 and PKC-ε,accompanied by an increases in ROS production,apoptosis rate,and monolayer permeability.However,silencing RACK1 significantly downregulated the expression of PKC-εand ROS,reduced cell apoptosis and permeability,and protected barrier function.CONCLUSION RACK1 plays a significant role in the development of early DR and might serve as a potential therapeutic target for DR by regulating RPE apoptosis and barrier function.
基金supported by grants from National Natural Science Foundation of China(No.81471519 and No.81401277)the Program for Changjiang Scholars and Innovative Research Team in University of China(No.IRT_14R20)
文摘Summary： Activated protein C （APC）, a natural anticoagulant, has been reported to exert direct vascu- loprotective, neural protective, anti-inflammatory, and proneurogenic activities in the central nervous system. This study was aimed to explore the neuroprotective effects and potential mechanisms of APC on the neurovascular unit of neonatal rats with intrauterine infection-induced white matter injury. In- traperitoneal injection of 300 ~tg/kg lipopolysaccharide （LPS） was administered consecutively to preg- nant Sprague-Dawley rats at embryonic days 19 and 20 to establish the rat model of intrauterine infec- tion-induced white matter injury. Control rats were injected with an equivalent amount of sterile saline on the same time. APC at the dosage of 0.2 mg/kg was intraperitoneally injected to neonatal rats imme- diately after birth. Brain tissues were collected at postnatal day 7 and stained with hematoxylin and eo- sin （H＆E）. Immunohistochemistry was used to evaluate myelin basic protein （MBP） expression in the periventricular white matter region. Blood-brain barrier （BBB） permeability and brain water content ~were measured using Evens Blue dye and wet/dry weight method. Double immunofluorescence staining and real-time quantitative PCR were performed to detect microglial activation and the expression of protease activated receptor 1 （PAR1）. Typical pathological changes of white matter injury were ob- served in rat brains exposed to LPS, and MBP expression in the periventricular region was significantly decreased. BBB was disrupted and the brain water content was increased. Microglia were largely acti- vated and the mRNA and protein levels of PAR1 were elevated. APC administration ameliorated the pathological lesions of the white matter and increased MBP expression. BBB permeability and brain water content were reduced. Microglia activation was inhibited and the PAR1 mRNA and protein ex- pression levels were both down-regulated. Our results suggested that APC exerted neuroprotective ef- fects on multiple components of the neurovascular unit in neonatal rats with intrauterine infec- tion-induced white matter injury, and the underlying mechanisms might involve decreased expression of PAR1.
文摘目的检测活化的蛋白激酶C受体1(RACK1)、低氧诱导因子1α(HIF-1α)、血管内皮生长因子(VEGF)在宫颈癌组织中的表达并探讨其病理学意义。方法选取2014年6月至2018年6月于本院行手术切除并经病理确诊的85例宫颈癌组织样本及其对应的癌旁组织,通过免疫组织化学染色ABC法分别检测RACK1、HIF-1α、VEGF蛋白在宫颈癌组织及其癌旁组织中的表达。结合患者的临床病理资料,分析宫颈癌组织中RACK1、HIF-1α和VEGF蛋白表达与患者年龄及肿瘤直径、浸润深度、病理分级、淋巴结转移之间的关系,并分析三者表达之间的相关性。结果RACK1、HIF-1α、VEGF蛋白在宫颈癌组织中的表达均高于癌旁组织(P均<0.05),阳性表达率分别为81.2%(69/85)、63.5%(54/85)、89.4%(76/85)。RACK1表达与肿瘤浸润深度、病理分级和淋巴结是否转移有关(P均<0.05),HIF-1α和VEGF表达均与肿瘤直径、浸润深度、病理分级及淋巴结是否转移有关(P均<0.05)。RACK1、HIF-1α、VEGF蛋白的表达两两之间呈正相关(RACK1 vs HIF-1α:r=0.523,P=0.0439;RACK1 vs VEGF:r=0.428,P=0.0337;HIF-1αvs VEGF:r=0.689,P=0.0245)。结论RACK1、HIF-1、VEGF蛋白在宫颈癌组织中高表达且三者之间的表达呈正相关,提示其可能在肿瘤的发生、发展过程中起协同作用,可作为判断肿瘤侵袭、转移及预后的重要指标。
文摘目的以GEO(Gene Expression Omnibus)数据库为基础分析活化的蛋白激酶C受体1(receptor for activated C kinase1,RACK1)在糖尿病肾小管病中的表达及可能的机制。方法通过搜索Nephroseq数据库及KEGG(Kyoto Encyclopedia of Genes and Genomes),明确RACK1在人的糖尿病肾小管病中表达情况及可能的通路。将培养的肾小管上皮细胞分为对照组、甘露醇组和高糖组,实时定量PCR测定其下游靶基因STAT1和STAT3的变化。FVB/N小鼠分为对照组和糖尿病肾病组,糖尿病肾病组小鼠给予腹腔注射链脲佐菌素构建糖尿病肾病的模型,实时定量PCR测定STAT1和STAT3 mRNA水平,免疫荧光染色明确p-STAT1和p-STAT3的表达情况。结果数据库数据分析发现RACK1在人糖尿病肾小管中表达明显升高。KEGG提示RACK1可能通过激活Jak-STAT信号通路发挥作用。与对照组比较,高糖组肾小管上皮细胞的RACK1、STAT1及STAT3的mRNA水平均明显升高,差异有统计学意义(P<0.05)。糖尿病肾病动物模型中,肾小管的RACK1、STAT1及STAT3的mRNA水平均明显升高,差异有统计学意义(P<0.05);免疫荧光示p-STAT1阳性,主要位于肾小管上皮细胞中。结论 RACK1在糖尿病肾小管中高表达,可能是通过磷酸化STAT1激活Jak-STAT信号通路参与糖尿病肾小管病的发生发展。
