Objective Epidemiological studies reveal that exposure to fine particulate matter(aerodynamic diameter≤2.5μm,PM_(2.5))increases the morbidity and mortality of respiratory diseases.Emerging evidence suggests that hum...Objective Epidemiological studies reveal that exposure to fine particulate matter(aerodynamic diameter≤2.5μm,PM_(2.5))increases the morbidity and mortality of respiratory diseases.Emerging evidence suggests that human circulating extracellular vesicles(EVs)may offer protective effects against injury caused by particulate matter.Currently,however,whether EVs attenuate PM_(2.5)-induced A549 cell apoptosis is unknown.Methods EVs were isolated from the serum of healthy subjects,quantified via nanoparticle tracking analysis,and qualified by the marker protein CD63.PM_(2.5)-exposed(50μg/mL)A549 cells were pretreated with 10μg/mL EVs for 24 h.Cell viability,cell apoptosis,and AKT activation were assessed via Cell Counting Kit-8,flow cytometry,and Western blot,respectively.A rescue experiment was also performed using MK2206,an AKT inhibitor.Results PM_(2.5)exposure caused a 100%in crease in cell apoptosis.EVs treatme nt reduced cell apoptosis by 10%,promoted cell survival,and inhibited the PM_(2.5)-induced upregulation of Bax/Bcl2 and cleaved caspase 3/caspase 3 in PM_(2.5)-exposed A549 cells.Moreover,EVs treatment reversed PM_(2.5)-induced reductions in p-AKT^(Thr308)and p-AKT^(Ser473).A KT inhibition attenuated the anti-apoptotic effect of EVs treatment on PM_(2.5)-exposed A549 cells.Conclusions EVs treatment promotes cell survival and attenuates PM_(2.5)-induced cell apoptosis via AKT phosphorylation.Human serum-derived EVs may be an efficacious novel therapeutic strategy in PM_(2.5)-induced lung injury.展开更多
基金supported by grants from the National Natural Science Foundation of China[NSFC31500618,awarded to GAO JNSFC82000253,awarded to WANG HY]sponsored by Shanghai Sailing Program[20YF1414000 to WANG HY]。
文摘Objective Epidemiological studies reveal that exposure to fine particulate matter(aerodynamic diameter≤2.5μm,PM_(2.5))increases the morbidity and mortality of respiratory diseases.Emerging evidence suggests that human circulating extracellular vesicles(EVs)may offer protective effects against injury caused by particulate matter.Currently,however,whether EVs attenuate PM_(2.5)-induced A549 cell apoptosis is unknown.Methods EVs were isolated from the serum of healthy subjects,quantified via nanoparticle tracking analysis,and qualified by the marker protein CD63.PM_(2.5)-exposed(50μg/mL)A549 cells were pretreated with 10μg/mL EVs for 24 h.Cell viability,cell apoptosis,and AKT activation were assessed via Cell Counting Kit-8,flow cytometry,and Western blot,respectively.A rescue experiment was also performed using MK2206,an AKT inhibitor.Results PM_(2.5)exposure caused a 100%in crease in cell apoptosis.EVs treatme nt reduced cell apoptosis by 10%,promoted cell survival,and inhibited the PM_(2.5)-induced upregulation of Bax/Bcl2 and cleaved caspase 3/caspase 3 in PM_(2.5)-exposed A549 cells.Moreover,EVs treatment reversed PM_(2.5)-induced reductions in p-AKT^(Thr308)and p-AKT^(Ser473).A KT inhibition attenuated the anti-apoptotic effect of EVs treatment on PM_(2.5)-exposed A549 cells.Conclusions EVs treatment promotes cell survival and attenuates PM_(2.5)-induced cell apoptosis via AKT phosphorylation.Human serum-derived EVs may be an efficacious novel therapeutic strategy in PM_(2.5)-induced lung injury.