BACKGROUND Non-invasive methods to diagnose non-alcoholic steatohepatitis(NASH),an inflammatory subtype of non-alcoholic fatty liver disease(NAFLD),are currently unavailable.AIM To develop an integrinαvβ3-targeted m...BACKGROUND Non-invasive methods to diagnose non-alcoholic steatohepatitis(NASH),an inflammatory subtype of non-alcoholic fatty liver disease(NAFLD),are currently unavailable.AIM To develop an integrinαvβ3-targeted molecular imaging modality to differentiate NASH.METHODS Integrinαvβ3 expression was assessed in Human LO2 hepatocytes Scultured with palmitic and oleic acids(FFA).Hepatic integrinαvβ3 expression was analyzed in rabbits fed a high-fat diet(HFD)and in rats fed a high-fat,high-carbohydrate diet(HFCD).After synthesis,cyclic arginine-glycine-aspartic acid peptide(cRGD)was labeled with gadolinium(Gd)and used as a contrast agent in magnetic resonance imaging(MRI)performed on mice fed with HFCD.RESULTS Integrinαvβ3 was markedly expressed on FFA-cultured hepatocytes,unlike the control hepatocytes.Hepatic integrinαvβ3 expression significantly increased in both HFD-fed rabbits and HFCD-fed rats as simple fatty liver(FL)progressed to steatohepatitis.The distribution of integrinαvβ3 in the liver of NASH cases largely overlapped with albumin-positive staining areas.In comparison to mice with simple FL,the relative liver MRI-T1 signal value at 60 minutes post-injection of Gd-labeled cRGD was significantly increased in mice with steatohepatitis(P<0.05),showing a positive correlation with the NAFLD activity score(r=0.945;P<0.01).Hepatic integrinαvβ3 expression was significantly upregulated during NASH development,with hepatocytes being the primary cells expressing integrinαvβ3.CONCLUSION After using Gd-labeled cRGD as a tracer,NASH was successfully distinguished by visualizing hepatic integrinαvβ3 expression with MRI.展开更多
目的:探讨罗汉果皂苷V(MV)对铁死亡诱导剂RAS选择性致死分子3(RSL3)诱导的人神经母细胞瘤SH-SY5Y细胞铁死亡的抑制作用及可能机制。方法:用RSL3诱导SH-SY5Y细胞建立铁死亡模型。MTT法检测细胞活力;倒置显微镜观察细胞形态;亚铁离子荧光...目的:探讨罗汉果皂苷V(MV)对铁死亡诱导剂RAS选择性致死分子3(RSL3)诱导的人神经母细胞瘤SH-SY5Y细胞铁死亡的抑制作用及可能机制。方法:用RSL3诱导SH-SY5Y细胞建立铁死亡模型。MTT法检测细胞活力;倒置显微镜观察细胞形态;亚铁离子荧光探针FerroFarRed检测细胞内亚铁离子含量;线粒体红色荧光探针MitoTracker Red CMXRos检测线粒体膜电位(MMP);超氧化物阴离子荧光探针二氢乙啶和线粒体超氧化物红色荧光探针MitoSoX Red分别检测细胞内和线粒体内活性氧(ROS)。微板法检测细胞谷胱甘肽(GSH)和丙二醛(MDA)水平。Western blot检测脂酰辅酶A合成酶长链家族成员4(ACSL4)、环加氧酶2(COX-2、)谷胱甘肽过氧化物酶4(GPX4)和溶质载体家族7成员11(SLC7A11)蛋白表达水平。分子对接技术预测MV与ACSL4、COX-2、GPX4和SLC7A11的靶向关系。结果:与control组相比,RSL3组SH-SY5Y细胞活力显著降低(P<0.01),细胞内亚铁离子含量、细胞内和线粒体内ROS水平及MDA水平显著升高(P<0.05或P<0.01),MMP和GSH水平显著降低(P<0.01),ACSL4和COX-2蛋白表达水平显著升高,而GPX4和SLC7A11蛋白表达水平显著降低(P<0.01),提示成功建立了细胞铁死亡模型。MV处理使细胞活力显著升高(P<0.05),细胞内亚铁离子含量、细胞内和线粒体内ROS水平及MDA水平显著降低(P<0.01),MMP和GSH水平显著升高(P<0.05或P<0.01);ACSL4和COX-2蛋白水平显著降低,而GPX4和SLC7A11蛋白水平显著升高(P<0.05或P<0.01)。分子对接结果显示,MV与铁死亡核心蛋白ACSL4、COX-2、GPX4和SLC7A11存在结合位点。结论:MV可抑制RSL3诱导的SH-SY5Y细胞铁死亡的发生,其机制可能与激活SLC7A11/GPX4和抑制ACSL4/COX-2有关。展开更多
Previous studies of integrin αvβ3 have focused on ischemic brain damage, although the role of integrin αvβ3 in ischemic preconditioning （IP） has rarely been reported. The present study analyzed the effects of IP...Previous studies of integrin αvβ3 have focused on ischemic brain damage, although the role of integrin αvβ3 in ischemic preconditioning （IP） has rarely been reported. The present study analyzed the effects of IP on integrin αvβ3 mRNA expression following cerebral ischemia through the use of hematoxylin-eosin staining and real-time quantitative polymerase chain reaction techniques. Integrin avid3 mRNA expression in the ischemia group peaked at 24 hours after ischemia-reperfusion. In the IP ＋ ischemia group, integrin αvβ3 mRNA expression increased after 24 hours, but remained significantly less than the ischemia group, and expression continued to increase until 7 days after ischemiaJreperfusion. These results demonstrate that IP effectively attenuated upregulation of integrin αvβ3 mRNA expression at 24 hours after ischemia.展开更多
Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic ...Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,respectively.However,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries.Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their reactivity.Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune response.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo results.In astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses.Here,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation.We highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and Notch/PI3K/AKT pathways.While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial outcomes.This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation.The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior.The findings should then be validated using in vivo models to ensure real-life relevance.The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage,although further studies are required to fully comprehend its role due to varying factors such as different cell types,astrocyte responses to inflammation,and disease contexts.Specific strategies are clearly necessary to address these variables effectively.展开更多
基金Supported by the National Natural Science Foundation of China,No.81670513and Young Scientists Fund of the National Natural Science Foundation of China,No.81900511。
文摘BACKGROUND Non-invasive methods to diagnose non-alcoholic steatohepatitis(NASH),an inflammatory subtype of non-alcoholic fatty liver disease(NAFLD),are currently unavailable.AIM To develop an integrinαvβ3-targeted molecular imaging modality to differentiate NASH.METHODS Integrinαvβ3 expression was assessed in Human LO2 hepatocytes Scultured with palmitic and oleic acids(FFA).Hepatic integrinαvβ3 expression was analyzed in rabbits fed a high-fat diet(HFD)and in rats fed a high-fat,high-carbohydrate diet(HFCD).After synthesis,cyclic arginine-glycine-aspartic acid peptide(cRGD)was labeled with gadolinium(Gd)and used as a contrast agent in magnetic resonance imaging(MRI)performed on mice fed with HFCD.RESULTS Integrinαvβ3 was markedly expressed on FFA-cultured hepatocytes,unlike the control hepatocytes.Hepatic integrinαvβ3 expression significantly increased in both HFD-fed rabbits and HFCD-fed rats as simple fatty liver(FL)progressed to steatohepatitis.The distribution of integrinαvβ3 in the liver of NASH cases largely overlapped with albumin-positive staining areas.In comparison to mice with simple FL,the relative liver MRI-T1 signal value at 60 minutes post-injection of Gd-labeled cRGD was significantly increased in mice with steatohepatitis(P<0.05),showing a positive correlation with the NAFLD activity score(r=0.945;P<0.01).Hepatic integrinαvβ3 expression was significantly upregulated during NASH development,with hepatocytes being the primary cells expressing integrinαvβ3.CONCLUSION After using Gd-labeled cRGD as a tracer,NASH was successfully distinguished by visualizing hepatic integrinαvβ3 expression with MRI.
文摘目的:探讨罗汉果皂苷V(MV)对铁死亡诱导剂RAS选择性致死分子3(RSL3)诱导的人神经母细胞瘤SH-SY5Y细胞铁死亡的抑制作用及可能机制。方法:用RSL3诱导SH-SY5Y细胞建立铁死亡模型。MTT法检测细胞活力;倒置显微镜观察细胞形态;亚铁离子荧光探针FerroFarRed检测细胞内亚铁离子含量;线粒体红色荧光探针MitoTracker Red CMXRos检测线粒体膜电位(MMP);超氧化物阴离子荧光探针二氢乙啶和线粒体超氧化物红色荧光探针MitoSoX Red分别检测细胞内和线粒体内活性氧(ROS)。微板法检测细胞谷胱甘肽(GSH)和丙二醛(MDA)水平。Western blot检测脂酰辅酶A合成酶长链家族成员4(ACSL4)、环加氧酶2(COX-2、)谷胱甘肽过氧化物酶4(GPX4)和溶质载体家族7成员11(SLC7A11)蛋白表达水平。分子对接技术预测MV与ACSL4、COX-2、GPX4和SLC7A11的靶向关系。结果:与control组相比,RSL3组SH-SY5Y细胞活力显著降低(P<0.01),细胞内亚铁离子含量、细胞内和线粒体内ROS水平及MDA水平显著升高(P<0.05或P<0.01),MMP和GSH水平显著降低(P<0.01),ACSL4和COX-2蛋白表达水平显著升高,而GPX4和SLC7A11蛋白表达水平显著降低(P<0.01),提示成功建立了细胞铁死亡模型。MV处理使细胞活力显著升高(P<0.05),细胞内亚铁离子含量、细胞内和线粒体内ROS水平及MDA水平显著降低(P<0.01),MMP和GSH水平显著升高(P<0.05或P<0.01);ACSL4和COX-2蛋白水平显著降低,而GPX4和SLC7A11蛋白水平显著升高(P<0.05或P<0.01)。分子对接结果显示,MV与铁死亡核心蛋白ACSL4、COX-2、GPX4和SLC7A11存在结合位点。结论:MV可抑制RSL3诱导的SH-SY5Y细胞铁死亡的发生,其机制可能与激活SLC7A11/GPX4和抑制ACSL4/COX-2有关。
基金the National Natural Science Foundation of China,No. 30870849,81071068the Science and Technology Planning Project of Guangdong Province,No. 2009B030801101
文摘Previous studies of integrin αvβ3 have focused on ischemic brain damage, although the role of integrin αvβ3 in ischemic preconditioning （IP） has rarely been reported. The present study analyzed the effects of IP on integrin αvβ3 mRNA expression following cerebral ischemia through the use of hematoxylin-eosin staining and real-time quantitative polymerase chain reaction techniques. Integrin avid3 mRNA expression in the ischemia group peaked at 24 hours after ischemia-reperfusion. In the IP ＋ ischemia group, integrin αvβ3 mRNA expression increased after 24 hours, but remained significantly less than the ischemia group, and expression continued to increase until 7 days after ischemiaJreperfusion. These results demonstrate that IP effectively attenuated upregulation of integrin αvβ3 mRNA expression at 24 hours after ischemia.
基金supported by Fondo Nacional de Desarrollo Científico y Tecnológico(FONDECYT)#1200836,#1210644,and#1240888,and Agencia Nacional de Investigación y Desarrollo(ANID)-FONDAP#15130011(to LL)FONDECYT#3230227(to MFG).
文摘Astrocytes are the most abundant type of glial cell in the central nervous system.Upon injury and inflammation,astrocytes become reactive and undergo morphological and functional changes.Depending on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,respectively.However,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and injuries.Transcriptomic analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their reactivity.Astrocytes actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune response.The phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo results.In astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory responses.Here,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their activation.We highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the PI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/PI3K/AKT/connexin 43,and Notch/PI3K/AKT pathways.While targeting the inactivation of the PI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial outcomes.This dual function of the PI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function modulation.The review emphasizes the importance of employing astrocyte-exclusive models to understand their functions accurately and these models are essential for clarifying astrocyte behavior.The findings should then be validated using in vivo models to ensure real-life relevance.The review also highlights the significance of PI3K/AKT pathway modulation in preventing central nervous system damage,although further studies are required to fully comprehend its role due to varying factors such as different cell types,astrocyte responses to inflammation,and disease contexts.Specific strategies are clearly necessary to address these variables effectively.
