OBJECTIVE To clarify the role of translocator protein 18 ku(TSPO)on cecum liga⁃tion and puncture(CLP)induced sepsis associat⁃ed encephalopathy(SAE)mice,which consis⁃tently demonstrated astrocyte activation and neu⁃roi...OBJECTIVE To clarify the role of translocator protein 18 ku(TSPO)on cecum liga⁃tion and puncture(CLP)induced sepsis associat⁃ed encephalopathy(SAE)mice,which consis⁃tently demonstrated astrocyte activation and neu⁃roinflammation.Background SAE,a brain dys⁃function,caused by systemic infection without clinical or laboratory evidence of direct infection.Most patients have symptoms such as long-term cognitive dysfunction.As the pathogenesis of SAE is very complex,neuroinflammation for SAE is one of the causes of the disease.TSPO as a marker of neuroinflammation that has the poten⁃tial to regulate neuroinflammation and SAE.METHODS The animal model of SAE was in⁃duced by CLP.TSPO ligands and TSPO knock⁃out mice were used for behavioral and molecular biology research.Survival rate of mice within 120 h on CLP mice was observed.The changes of cog⁃nitive function in mice were observed by Morris water maze and open field test.The changes of proinflammatory factors(IL-1β,TNF-α,IL-6)in hippocampus were observed by ELISA;Astro⁃cyte activation,marked by GFAP,in hippocam⁃pal was analyzed by tissue immunofluorescence and Western blotting.RESULTS Pretreatment with the TSPO ligands,XBD173 or PK11195,sig⁃nificantly improved the survival rate of CLP mice.The results of Morris water maze showed that TSPO ligands significantly increased the number of crossing the platform and the target quadrant time on CLP mice,suggesting that TSPO ligands may improve the learning and memory ability of CLP mice.Subsequent experiments revealed that TSPO ligands can reduce the inflammatory factors(IL-1β,TNF-α,IL-6)and astrocyte activa⁃tion in hippocampus of CLP mice.Similar results were also confirmed in TSPO knockout CLP mice,suggesting intervention of TSPO can reduce neuroinflammatory response and play a protec⁃tive role on SAE mice.CONCLUSION TSPO may play a critical role on SAE mice.Targeting TSPO by pharmacological means may improve the survival rate and cognitive function on CLP mice,which may through inhibiting astrocyte acti⁃vation and neuroinflammation in hippocampal.展开更多
The normal development and optimal functioning of the brain requires a vigilant immune surveillance system to detect and remove potential risk factors and prevent infection and tissue damage. Microglia are the residen...The normal development and optimal functioning of the brain requires a vigilant immune surveillance system to detect and remove potential risk factors and prevent infection and tissue damage. Microglia are the resident immune cells and the frontline defenders responsible for the immune response of the brain. Resting microglia possess a ramified morphology with numerous thin processes that continuously sample the environment. In response to inflammatory signals, microglia become activated and transform their morphology into a thick, amoeboid-like shape. Activated microglia proliferate, tolerate to sites of iniurv,展开更多
Background:Acute respiratory distress syndrome(ARDS)is a common cause of respiratory failure in many critically ill patients.Although inflammasome activation plays an important role in the induction of acute lung inju...Background:Acute respiratory distress syndrome(ARDS)is a common cause of respiratory failure in many critically ill patients.Although inflammasome activation plays an important role in the induction of acute lung injury(ALI)and ARDS,the regulatory mechanism of this process is still unclear.When cells are stimulated by inflammation,the integrity and physiological function of mitochondria play a crucial part in pyroptosis.However,the underlying mechanisms and function of mitochondrial proteins in the process of pyroptosis are largely not yet known.Here,we identified the 18-kDa translocator protein(TSPO),a mitochondrial outer membrane protein,as an important mediator regulating nucleotide-binding domain,leucine-rich repeat,and pyrin domain-containing protein 3(NLRP3)inflammasome activation in macrophages during ALI.Methods:TSPO gene knockout(KO)and lipopolysaccharide(LPS)-induced ALI/ARDS mouse models were employed to investigate the biological role of TSPO in the pathogenesis of ARDS.Murine macrophages were used to further characterize the effect of TSPO on the NLRP3 inflammasome pathway.Activation of NLRP3 inflammasome was preformed through LPS+adenosine triphosphate(ATP)co-stimulation,followed by detection of mitochondrial membrane potential,reactive oxygen species(ROS)production,and cell death to evaluate the potential biological function of TSPO.Comparisons between two groups were performed with a two-sided unpaired t-test.Results:TSPO-KO mice exhibited more severe pulmonary inflammation in response to LPS-induced ALI.TSPO deficiency resulted in enhanced activation of the NLRP3 inflammasome pathway,promoting more proinflammatory cytokine production of macrophages in LPS-injured lung tissue,including interleukin(IL)-1β,IL-18,and macrophage inflammatory protein(MIP)-2.Mitochondria in TSPO-KO macrophages tended to depolarize in response to cellular stress.The increased production of mitochondrial damage-associated molecular pattern led to enhanced mitochondrial membrane depolarization and pyroptosis in TSPO-KO cells.Conclusion:TSPO may be the key regulator of cellular pyroptosis,and it plays a vital protective role in ARDS occurrence and development.展开更多
基金Joint Funds for the Innovation of Science and Technology of Fujian Province(2019Y9009)and Natural Science Foundation of Fujian Province(2020J01618)。
文摘OBJECTIVE To clarify the role of translocator protein 18 ku(TSPO)on cecum liga⁃tion and puncture(CLP)induced sepsis associat⁃ed encephalopathy(SAE)mice,which consis⁃tently demonstrated astrocyte activation and neu⁃roinflammation.Background SAE,a brain dys⁃function,caused by systemic infection without clinical or laboratory evidence of direct infection.Most patients have symptoms such as long-term cognitive dysfunction.As the pathogenesis of SAE is very complex,neuroinflammation for SAE is one of the causes of the disease.TSPO as a marker of neuroinflammation that has the poten⁃tial to regulate neuroinflammation and SAE.METHODS The animal model of SAE was in⁃duced by CLP.TSPO ligands and TSPO knock⁃out mice were used for behavioral and molecular biology research.Survival rate of mice within 120 h on CLP mice was observed.The changes of cog⁃nitive function in mice were observed by Morris water maze and open field test.The changes of proinflammatory factors(IL-1β,TNF-α,IL-6)in hippocampus were observed by ELISA;Astro⁃cyte activation,marked by GFAP,in hippocam⁃pal was analyzed by tissue immunofluorescence and Western blotting.RESULTS Pretreatment with the TSPO ligands,XBD173 or PK11195,sig⁃nificantly improved the survival rate of CLP mice.The results of Morris water maze showed that TSPO ligands significantly increased the number of crossing the platform and the target quadrant time on CLP mice,suggesting that TSPO ligands may improve the learning and memory ability of CLP mice.Subsequent experiments revealed that TSPO ligands can reduce the inflammatory factors(IL-1β,TNF-α,IL-6)and astrocyte activa⁃tion in hippocampus of CLP mice.Similar results were also confirmed in TSPO knockout CLP mice,suggesting intervention of TSPO can reduce neuroinflammatory response and play a protec⁃tive role on SAE mice.CONCLUSION TSPO may play a critical role on SAE mice.Targeting TSPO by pharmacological means may improve the survival rate and cognitive function on CLP mice,which may through inhibiting astrocyte acti⁃vation and neuroinflammation in hippocampal.
基金supported by the Bio&Medical Technology Development Program of the National Research Foundation of Korea(NRF)grant(No.2012M3A9C6049935)the DGIST Convergence Science Center Program(15-BD-04)of the Ministry of Science,ICT and Future Planning of Korea
文摘The normal development and optimal functioning of the brain requires a vigilant immune surveillance system to detect and remove potential risk factors and prevent infection and tissue damage. Microglia are the resident immune cells and the frontline defenders responsible for the immune response of the brain. Resting microglia possess a ramified morphology with numerous thin processes that continuously sample the environment. In response to inflammatory signals, microglia become activated and transform their morphology into a thick, amoeboid-like shape. Activated microglia proliferate, tolerate to sites of iniurv,
基金National Natural Science Foundation of China(Nos.82071791,32270915,U20A20374,31970843,and 81972886)National Key Research and Development Program of China(No.2022YFC3602004)+4 种基金CAMS Initiative for Innovative Medicine(Nos.2021-I2M-1-005,2021-I2M-1-035,2021-I2M-1-053,and 2022-I2M-CoV19-007)Haihe Laboratory of Cell Ecosystem Innovation Fund(No.22HHXBSS00028)CAMS Central Public Welfare Scientific Research Institute Basal Research Expenses(No.3332020035)Changzhou Science and Technology Support Plan(No.CE20215008)Beijing Municipal Commission of Science and Technology Fund for Innovative Drugs(No.Z221100007922040)
文摘Background:Acute respiratory distress syndrome(ARDS)is a common cause of respiratory failure in many critically ill patients.Although inflammasome activation plays an important role in the induction of acute lung injury(ALI)and ARDS,the regulatory mechanism of this process is still unclear.When cells are stimulated by inflammation,the integrity and physiological function of mitochondria play a crucial part in pyroptosis.However,the underlying mechanisms and function of mitochondrial proteins in the process of pyroptosis are largely not yet known.Here,we identified the 18-kDa translocator protein(TSPO),a mitochondrial outer membrane protein,as an important mediator regulating nucleotide-binding domain,leucine-rich repeat,and pyrin domain-containing protein 3(NLRP3)inflammasome activation in macrophages during ALI.Methods:TSPO gene knockout(KO)and lipopolysaccharide(LPS)-induced ALI/ARDS mouse models were employed to investigate the biological role of TSPO in the pathogenesis of ARDS.Murine macrophages were used to further characterize the effect of TSPO on the NLRP3 inflammasome pathway.Activation of NLRP3 inflammasome was preformed through LPS+adenosine triphosphate(ATP)co-stimulation,followed by detection of mitochondrial membrane potential,reactive oxygen species(ROS)production,and cell death to evaluate the potential biological function of TSPO.Comparisons between two groups were performed with a two-sided unpaired t-test.Results:TSPO-KO mice exhibited more severe pulmonary inflammation in response to LPS-induced ALI.TSPO deficiency resulted in enhanced activation of the NLRP3 inflammasome pathway,promoting more proinflammatory cytokine production of macrophages in LPS-injured lung tissue,including interleukin(IL)-1β,IL-18,and macrophage inflammatory protein(MIP)-2.Mitochondria in TSPO-KO macrophages tended to depolarize in response to cellular stress.The increased production of mitochondrial damage-associated molecular pattern led to enhanced mitochondrial membrane depolarization and pyroptosis in TSPO-KO cells.Conclusion:TSPO may be the key regulator of cellular pyroptosis,and it plays a vital protective role in ARDS occurrence and development.
