Mechanisms Of Prothymosin Alpha(PTMA) In The Occurrence And Development Of Aortic Dissections

Objective:The objective of this study is to clarify the expression and distribution of Prothymosin alpha(PTMA)in human aortic dissection(AD),and to investigate its functional effect.Further exploration of specific targets and signaling pathways regulated by PTMA,to provide experimental basis for early biomarker diagnosis and molecular targeted therapy of arterial dissection.Methods:① The differential expression of mRNA of aortic dissection were investigated by gene chip and bioinformatics analysis methods.The expression and location distribution of PTMA in aortic were tested by qRT-PCR,Western blotting(WB)and immunohistochemistry.②Using C57BL/6J mice to making aortic dissection model by β-aminopropionitrile(BAPN)and angiotensin II.Tail vein injection was used to interfere sh-PTMA in vivo;C57BL/6J mouse were randomly divided into four groups:control group,AD group,control+sh-PTMA group and AD+sh-PTMA group.After 24h of Ang II infusion,the AD formation rate and aortic diameter were measured in mice after euthanasia,qRTPCR and WB were used to confirm the interfering effect.③Constructing the siRNA to interfere the expression level of PTMA in HASMC.QRTPCR and Western blotting were used to verified the interfering effect of siRNA.The proliferation and apootosis of HASMC was detected by wound healing assay and flow cytometry.④ Functional enrichment and PPI network was constructed by bioinformatics analysis methods,screen out PTMA interacting proteins.Results:① The differential expression of mRNA of aorta.We obtained total of 103 mRNAs(54 up-regulated and 49 down-regulated)were significantly aberrantly expressed in TAD tissues by bioinformatics analysis methods.PTMA was selected for follow-up experimental verification,and the results showed that the PTMA was significantly over-expressed in TAD tissues compared with the normal tissues.And we found that IHC showed high expression of PTMA in the aortic vessel wall.②Targeting PTMA influences the development of AD.AAV serotype-9 was used to constructed the sh-PTMA AD model.Compared with the AD group,the incidence and formation of AD in the AD+sh-PTMA group were significantly reduced.③ PTMA regulated the proliferation and apoptosis of HASMCs.The si-PTMA was constructed,the wound healing assay showed the knockdown of PTMA attenuated H2O2-induced HASMCs apoptosis.The flow cytometry tests showed that compared with the control group,down-regulated of PTMA significantly reduced the apoptosis.④ Explore the mechanism of PTMA regulating the HASMCs.Bioinformatics analysis revealed that PTMA is functionally enriched in cellular,organic,and nitrogen compound metabolic processes;and there may be an interaction with KEAP1,APAF1,NUPR1,H1F0,PTMS,EP300,SUMO2,PTGES3,ACTR3 and SLC6A7.And we found that PTMA was able to inhibit the antioxidant response capacity in SMCs by regulating the KEAP1-NRF2 pathway.Conclusion:PTMA targets KEAP1,APAF1,NUPR1,H1F0,PTMS,EP300,SUMO2,PTGES3,ACTR3 and SLC6A7 to regulate the apoptosis of HASMCs and ultimately leads to the formation and development of AD.