Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apopt...Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma.展开更多
信息化平台建设是实验教学中心提高管理水平、实现优质教学资源共享、更好地发挥示范辐射作用、确保开放运行质量的必要保证,在实验中心的建设过程中具有重要作用。为进一步提高信息化管理水平,西南交通大学国家级机械基础实验中心在原...信息化平台建设是实验教学中心提高管理水平、实现优质教学资源共享、更好地发挥示范辐射作用、确保开放运行质量的必要保证,在实验中心的建设过程中具有重要作用。为进一步提高信息化管理水平,西南交通大学国家级机械基础实验中心在原有网络化管理系统的基础上,采用ASP.NET 3.5与SQL SERVER 2008相结合,重新开发建设了信息化管理平台。系统架构由客户端层、应用逻辑层、数据库层3个层次组成,具有易扩展、易维护、开放化、智能化和安全可靠等特点。展开更多
基金supported by the National Natural Science Foundation of China,Nos.32271043(to ZW)and 82171047(to YM)the both Science and Technology Major Project of Shanghai,No.2018SHZDZX01 and ZJLabShanghai Center for Brain Science and Brain-Inspired Technology(to ZW)。
文摘Downregulation of the inwardly rectifying potassium channel Kir4.1 is a key step for inducing retinal Müller cell activation and interaction with other glial cells,which is involved in retinal ganglion cell apoptosis in glaucoma.Modulation of Kir4.1 expression in Müller cells may therefore be a potential strategy for attenuating retinal ganglion cell damage in glaucoma.In this study,we identified seven predicted phosphorylation sites in Kir4.1 and constructed lentiviral expression systems expressing Kir4.1 mutated at each site to prevent phosphorylation.Following this,we treated Müller glial cells in vitro and in vivo with the m Glu R I agonist DHPG to induce Kir4.1 or Kir4.1 Tyr^(9)Asp overexpression.We found that both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited activation of Müller glial cells.Subsequently,we established a rat model of chronic ocular hypertension by injecting microbeads into the anterior chamber and overexpressed Kir4.1 or Kir4.1 Tyr^(9)Asp in the eye,and observed similar results in Müller cells in vivo as those seen in vitro.Both Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression inhibited Müller cell activation,regulated the balance of Bax/Bcl-2,and reduced the m RNA and protein levels of pro-inflammatory factors,including interleukin-1βand tumor necrosis factor-α.Furthermore,we investigated the regulatory effects of Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression on the release of pro-inflammatory factors in a co-culture system of Müller glial cells and microglia.In this co-culture system,we observed elevated adenosine triphosphate concentrations in activated Müller cells,increased levels of translocator protein(a marker of microglial activation),and elevated interleukin-1βm RNA and protein levels in microglia induced by activated Müller cells.These changes could be reversed by Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression in Müller cells.Kir4.1 overexpression,but not Kir4.1 Tyr^(9)Asp overexpression,reduced the number of proliferative and migratory microglia induced by activated Müller cells.Collectively,these results suggest that the tyrosine residue at position nine in Kir4.1 may serve as a functional modulation site in the retina in an experimental model of glaucoma.Kir4.1 and Kir4.1 Tyr^(9)Asp overexpression attenuated Müller cell activation,reduced ATP/P2X receptor–mediated interactions between glial cells,inhibited microglial activation,and decreased the synthesis and release of pro-inflammatory factors,consequently ameliorating retinal ganglion cell apoptosis in glaucoma.
文摘信息化平台建设是实验教学中心提高管理水平、实现优质教学资源共享、更好地发挥示范辐射作用、确保开放运行质量的必要保证,在实验中心的建设过程中具有重要作用。为进一步提高信息化管理水平,西南交通大学国家级机械基础实验中心在原有网络化管理系统的基础上,采用ASP.NET 3.5与SQL SERVER 2008相结合,重新开发建设了信息化管理平台。系统架构由客户端层、应用逻辑层、数据库层3个层次组成,具有易扩展、易维护、开放化、智能化和安全可靠等特点。
