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
The photosynthetic apparatus of plant is localised in chloroplasts. During the photosynthesis, the absorption, transfer and conversion, of light energy, water-splitting reaction and photophosphorylation take place in ...The photosynthetic apparatus of plant is localised in chloroplasts. During the photosynthesis, the absorption, transfer and conversion, of light energy, water-splitting reaction and photophosphorylation take place in the chlorophyll-protein complexes of geometrically arranged pigments and proteins embedded in thylakoid membranes. The turnover of thylakoid membrane proteins requires various proteolytic activities. The Dl reaction center protein (Q_B-binding protein) has been demonstrated to require展开更多
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.
基金Project supported by the National Natural Science Foundation of China and Grants-in-Aid of Sichuan University.
文摘The photosynthetic apparatus of plant is localised in chloroplasts. During the photosynthesis, the absorption, transfer and conversion, of light energy, water-splitting reaction and photophosphorylation take place in the chlorophyll-protein complexes of geometrically arranged pigments and proteins embedded in thylakoid membranes. The turnover of thylakoid membrane proteins requires various proteolytic activities. The Dl reaction center protein (Q_B-binding protein) has been demonstrated to require
