Dobutamine Up-regulates Aquaporin 5 Expression In Septic Pulmonary Edema Model In Vitro Via CAMP-PKA/CREB Signaling Pathway

ObjectivesThe present study aimed to investigate the effect of dobutamine on the expression of AQP5 and its possible molecular mechanism in sepsis pulmonary edema.MethodsHuman lung adenocarcinoma A549 cells were exposed to LPS to establish septic pulmonary edema cell model,and then treated with dobutamine,8-Br-cAMP,the β-adrenalin receptor inhibitor ICI 118,551 and the PKA inhibitor H-89.The cells were divided into the control group(group A),LPS group(group B),LPS + dobutamine group(group C),LPS + dobutamine + ICI 118551 group(group D),LPS + dobutamine + H-89 group(group E),LPS + 8-Br-cAMP group(group F)and LPS + 8-Br-cAMP + H-89 group(group G).At the same time,the ultrastructure,the survival rate and the level of cAMP of the cells,and the expression of mRNA and protein of AQP5,PKA,cat and p-CREB were detected.ResultsThe cytoarchitecture observed by electron microscopic was intact,abundant cytoplasm,no obvious damage of various organelles in group A.In group B,the number of microvilli on the surface of cells was reduced,a large number of vacuoles appeared in the cells,and mitochondria and endoplasmic reticulum all had any damage.Compared with group B,the damage of cell structure was obviously reduced in group C and group F.The structure of electron microscope in group E of group D was similar,and the damage of cells were more serious than that in group C,the damage of cells were in group G more serious than that in group F.The survival rate was basically normal in group A.Compared with group A,the survival rate was significantly decreased in group B(P<0.01).Compared with group B,the cell survival rate was significantly increased in group C and group F(P<0.01),and the cell survival rate of group D and group E was significantly lower than that of group C(P<0.01),the cell survival rate of group G more serious than that in group F(P<0.01).The expression of AQP5 was normal in group A.Compared with group A,the expression of AQP5 on mRNA group and protein level was decreased significantly in group B(P<0.01).Compared with B group,the expression of AQP5 on mRNA and protein was increased significantly in group C and group F(P<0.01),and the expression of AQP5 in group D and group E were significantly lower than that in group C(P<0.01),the expression of AQP5 in group G were significantly lower than that in group F(P<0.01).The cAMP level was normal in group A.Compared with group A,the cAMP level was decreased significantly in group B(P<0.01).Compared with B group,the cAMP level was increased significantly in group C(P<0.01),the cAMP level in group D was significantly lower than that in group C(P<0.01),but there was no obvious difference between group C and group E.The PKAα cat protein growth trend was consistent with the p-CREB protein.The expression of PKAα cat protein and p-CREB protein were normal in group A.Compared with group A,the PKAα cat protein and p-CREB protein were decreased significantly in group B(P<0.01).Compared with B group,the PKAα cat protein and p-CREB protein were increased significantly in group C and group F(P<0.01),and the PKAα cat protein and p-CREB protein in group D and group E were significantly lower than that in group C(P<0.01),at the same time,the PKAα cat protein and p-CREB protein in group G were significantly lower than that in group F(P<0.01).ConclusionDobutamine contributed to a significant increase in AQP5 expression in sepsis pulmonary edema.And the possible molecular mechanism was achieved by upregulating the cAMP-PKA/CREB signaling pathway.