Molecular Mechanism Of Osteopontin Regulating Autophagy Of Pulmonary Artery Smooth Muscle Cells Through P38MAPK Signal Pathway

Objective The expression of autophagy-related factors and and the signal molecule in pulmonary arterial smooth muscle cell(PASMC)mediated by osteopontin(OPN)were investigated to clarify the molecular mechanism of OPN-mediated autophagy in PASMC.Methods After the primary isolated PASMC was intervened by OPN,the protein expression levels of autophagy-related factors(Beclin-1,LC3B)and key signal molecule(p38MAPK)were determined by Western blot assay.The expression levels of autophagy-related factors(Belin1,LC3B)at the gene transcriptional level were determined by RT-PCR assay.The effect of OPN on the proliferation of PASMC was detected by MTT value-added assay.The experimental groups were Control group(OPN:0ng/m L),OPN low concentration group(OPN:200ng/m L),OPN high concentration group(OPN:500ng/m L)and OPN low concentration +p38MAPK inhibitor group(OPN:200ng/m L + SB203580:10μM).Result 1.To be directed against the expression of autophagy protein,the expression of Beclin-1 and LC3 B proteins were significantly lower in the OPN low concentration group and OPN high concentration group compared with the Control group(P<0.05).2.In regard to gene transcription,the expression of Belin1 and LC3 B was significantly lower in the OPN low concentration group and OPN high concentration group compared with the Control group(P<0.05).3.In regard to expression of signal protein,the expression of p38 MAPK protein was significantly higher in the OPN low concentration group and OPN high concentration group compared with the Control group(P<0.05).4.To be directed against the level of cell proliferation,Compared with Control group,the proliferation level of pulmonary artery smooth muscle cells in each OPN group significantly increased(P<0.05).There was no significant change in the proliferation level of pulmonary artery smooth muscle cells in the OPN low concentration + p38 MAPK inhibitor group,compared with the OPN low concentration group(P>0.05).Conclusion To a certain extent,OPN can inhibit the expression of autophagy factors(Beclin-1 and LC3B)in PASMC and promote the proliferation of pulmonary artery smooth muscle cells.And OPN can inhibit the autophagy of pulmonary artery smooth muscle cells through p38 MAPK signal pathway.