Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection disrupts the epithelial barrier and triggers airway inflammation.The envelope(E)protein,a core virulence structural component of coronaviruses,may p...Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection disrupts the epithelial barrier and triggers airway inflammation.The envelope(E)protein,a core virulence structural component of coronaviruses,may play a role in this process.Pathogens could interfere with transepithelial Cl^(-)transport via impairment of the cystic fibrosis transmembrane conductance regulator(CFTR),which modulates nuclear factor kB(NF-kB)signaling.However,the pathological effects of SARS-CoV-2 E protein on airway epithelial barrier function,Cl^(-)transport and the robust inflammatory response remain to be elucidated.Here,we have demonstrated that E protein down-regulated the expression of tight junctional proteins,leading to the disruption of the airway epithelial barrier.In addition,E protein triggered the activation of Toll-like receptor(TLR)2/4 and downstream c-Jun N-terminal kinase(JNK)signaling,resulting in an increased intracellular Cl^(-)concentration([Cl^(-)]_(i))via up-regulating phosphodiesterase 4D(PDE4D)expression in airway epithelial cells.This elevated[Cl^(-)]_(i);contributed to the heightened airway inflammation through promoting the phosphorylation of serum/glucocorticoid regulated kinase 1(SGK1).Moreover,blockade of SGK1 or PDE4 alleviated the robust inflammatory response induced by E protein.Overall,these findings provide novel insights into the pathogenic role of SARS-CoV-2 E protein in airway epithelial damage and the ongoing airway inflammation during SARS-CoV-2 infection.展开更多
SARS-CoV-2,the culprit pathogen of COVID-19,elicits prominent immune responses and cytokine storms.Intracellular Cl^(−)is a crucial regulator of host defense,whereas the role of Cl^(−)signaling pathway in modulating p...SARS-CoV-2,the culprit pathogen of COVID-19,elicits prominent immune responses and cytokine storms.Intracellular Cl^(−)is a crucial regulator of host defense,whereas the role of Cl^(−)signaling pathway in modulating pulmonary inflammation associated with SARS-CoV-2 infection remains unclear.By using human respiratory epithelial cell lines,primary cultured human airway epithelial cells,and murine models of viral structural protein stimulation and SARS-CoV-2 direct challenge,we demonstrated that SARS-CoV-2 nucleocapsid(N)protein could interact with Smad3,which downregulated cystic fibrosis transmembrane conductance regulator(CFTR)expression via microRNA-145.The intracellular Cl^(−)concentration([Cl^(−)]i)was raised,resulting in phosphorylation of serum glucocorticoid regulated kinase 1(SGK1)and robust inflammatory responses.Inhibition or knockout of SGK1 abrogated the N protein-elicited airway inflammation.Moreover,N protein promoted a sustained elevation of[Cl^(−)]i by depleting intracellular cAMP via upregulation of phosphodiesterase 4(PDE4).Rolipram,a selective PDE4 inhibitor,countered airway inflammation by reducing[Cl^(−)]i.Our findings suggested that Cl^(−)acted as the crucial pathological second messenger mediating the inflammatory responses after SARS-CoV-2 infection.Targeting the Cl^(−)signaling pathway might be a novel therapeutic strategy for COVID-19.展开更多
基金supported by the National Science Foundation-Outstanding Youth Fund [grant number 82222001]the Guangzhou Institute of Respiratory Health Open Project (Funds provided by China Evergrande Group+2 种基金Project No.2020GIRHHMS13,2020GIRHHMS24)the Zhongnanshan Medical Foundation of Guangdong Province (ZNSA-2020012 and ZNSA-2020013)the Science and Technology Planning Project of Guangdong Province (2023B1212060028).
文摘Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection disrupts the epithelial barrier and triggers airway inflammation.The envelope(E)protein,a core virulence structural component of coronaviruses,may play a role in this process.Pathogens could interfere with transepithelial Cl^(-)transport via impairment of the cystic fibrosis transmembrane conductance regulator(CFTR),which modulates nuclear factor kB(NF-kB)signaling.However,the pathological effects of SARS-CoV-2 E protein on airway epithelial barrier function,Cl^(-)transport and the robust inflammatory response remain to be elucidated.Here,we have demonstrated that E protein down-regulated the expression of tight junctional proteins,leading to the disruption of the airway epithelial barrier.In addition,E protein triggered the activation of Toll-like receptor(TLR)2/4 and downstream c-Jun N-terminal kinase(JNK)signaling,resulting in an increased intracellular Cl^(-)concentration([Cl^(-)]_(i))via up-regulating phosphodiesterase 4D(PDE4D)expression in airway epithelial cells.This elevated[Cl^(-)]_(i);contributed to the heightened airway inflammation through promoting the phosphorylation of serum/glucocorticoid regulated kinase 1(SGK1).Moreover,blockade of SGK1 or PDE4 alleviated the robust inflammatory response induced by E protein.Overall,these findings provide novel insights into the pathogenic role of SARS-CoV-2 E protein in airway epithelial damage and the ongoing airway inflammation during SARS-CoV-2 infection.
基金supported by the Guangzhou Institute of Respiratory Health Open Project(Funds provided by China Evergrande Group)-Project No.2020GIRHHMS13,2020GIRHHMS24,Zhongnanshan Medical Foundation of Guangdong Province(ZNSA-2020012)the National Natural Science Foundation of China(No.81802031 and 31771286)。
文摘SARS-CoV-2,the culprit pathogen of COVID-19,elicits prominent immune responses and cytokine storms.Intracellular Cl^(−)is a crucial regulator of host defense,whereas the role of Cl^(−)signaling pathway in modulating pulmonary inflammation associated with SARS-CoV-2 infection remains unclear.By using human respiratory epithelial cell lines,primary cultured human airway epithelial cells,and murine models of viral structural protein stimulation and SARS-CoV-2 direct challenge,we demonstrated that SARS-CoV-2 nucleocapsid(N)protein could interact with Smad3,which downregulated cystic fibrosis transmembrane conductance regulator(CFTR)expression via microRNA-145.The intracellular Cl^(−)concentration([Cl^(−)]i)was raised,resulting in phosphorylation of serum glucocorticoid regulated kinase 1(SGK1)and robust inflammatory responses.Inhibition or knockout of SGK1 abrogated the N protein-elicited airway inflammation.Moreover,N protein promoted a sustained elevation of[Cl^(−)]i by depleting intracellular cAMP via upregulation of phosphodiesterase 4(PDE4).Rolipram,a selective PDE4 inhibitor,countered airway inflammation by reducing[Cl^(−)]i.Our findings suggested that Cl^(−)acted as the crucial pathological second messenger mediating the inflammatory responses after SARS-CoV-2 infection.Targeting the Cl^(−)signaling pathway might be a novel therapeutic strategy for COVID-19.
