Research On Screening Potential Intervention Targets For Aortic Valvular Disease Based On Bioinformatics Analysis

Background:As the problem of aging population is becoming more and more serious,the prevalence of aortic valve disease,particularly calcific aortic valve disease(CAVD)and aortic regurgitation(AR),is increasing,yet the rate of progression is low and therefore often been overlooked.Although the majority of patients with only mild disease,early aortic valve disease can also cause hemodynamic disturbances around the aortic valve,thereby increasing the risk of cardiovascular death and readmission,and increasing the burden in older patients.Currently,the treatment of aortic valve disease is limited,surgical treatment is only available for severe patients who can tolerate it,and there is no specific treatment for mild patients.Bioinformatics is a new subject which obtains biological information data based on gene chip and sequencing technology and then stores,retrieves and analyzes the data by computer.It can be used for the screening of disease related genes and proteins and the prediction of their structures and functions,providing a new direction for disease research.Epigenetic alterations are currently thought to play an important role in aortic valve disease,which provides a possible basis for targeted therapy.This study hopes to explore potential targets for aortic valve disease through bioinformatics analysis and provide new ideas for its prevention and diagnosis.Objectives:1.Explore the relationship between CAVD and cardiovascular diseases,heart structure and function through clinical data analysis;2.Screen out the DEGs and enrichment pathways of CAVD through bioinformatics analysis,and search the key cells infiltrated in the valve tissues of CAVD patients,thereby providing possible intervention targets for the diagnosis and treatment of CAVD;3.Through clinical data and bioinformatics analysis,explore independent risk factors for mild AR and screen out DEGs and enrichment pathways for AR,thereby providing possible targets for early intervention in the diagnosis and treatment of AR.Methods:1.The data of 176 patients in the department of cardiovascular medicine of 904 Hospital of the Joint Logistic Support Force were retrospectively analyzed.According to the presence or absence of aortic valve calcification diagnosed by echocardiography,patients were divided into non-CAVD group(88 cases)and CAVD group(88 cases),general data and echocardiographic examination data of each patient were recorded,and the relationship between CAVD and cardiovascular diseases,cardiac structure and function were analyzed by statistical methods.2.The existing information chips of human CAVD were obtained from GEO database to screen out DEGs between normal aortic valve and CAVD valve;The function and pathway of DEGs were analyzed by GO and KEGG enrichment.PPI network was constructed by String database and Cytoscape software,and the key genes were screened out.The CIBERSORT data package was used to calculate the infiltrating proportion of 22 kinds of immune cell in CAVD;3.The data of 741 adults in the physical examination center of 904 Hospital of the Joint Logistic Support Force were retrospectively analyzed.According to the presence or absence of aortic valve regurgitation diagnosed by echocardiography,there were602 cases included in the NAR group and 139 cases in the AR group.The related factors of mild AR were analyzed by statistical method;4.The existing information chips of human AR and AD were obtained from GEO database,and DEGs between normal aortic valve and AR valve,normal aortic tissue and AD tissue were screened out.The CIBERSORT data package was used to calculate the infiltrating proportion of 22 kinds of immune cells in AR and AD.Common DEGs of AR and AD were found out,and the function and pathway of common DEGs were analyzed by GO and KEGG enrichment.PPI network was constructed by String database and Cytoscape software,and the key genes were screened out.Results:1.Comparison of general data showed that the patients of CAVD group were older and the proportion of heart failure,atrial fibrillation,aortic sclerosis and carotid atherosclerosis was higher,the differences were statistically significant(P<0.05).Comparison of echocardiographic results showed that the patients of CAVD group had smaller aortic valvular opening,larger left atrial diameter,lower ejection fraction(EF),higher proportion of aortic valve regurgitation and larger regurgitation,the differences were statistically significant(P < 0.05).2.Through text mining and data analysis,95 DEGs were found between the normal aortic valve tissues and calcified aortic valve tissues,including 64 up-regulated genes and 31 down-regulated genes.Through GO analysis,these DEGs were enriched in117 biological processes such as extracellular matrix organization,extracellular structure organization and external encapsulating structure organization,13 cell components such as collagen-containing extracellular matrix,endoplasmic reticulum lumen,collagen trimer and 33 molecular functions such as extracellular matrix structural constituent,integrin binding and extracellular matrix structural constituent conferring tensile strength.KEGG analysis showed that DEGs enriched in 10 pathways such as protein digestion and absorption,PI3K-Akt signaling pathway,focal adhesion.Ten key genes(COL4A2,COL4A1,COL3A1,THBS2,COL5A1,COL5A2,COL4A4,COL11A1,FN1 and COL4A3)and two gene modules were screened by PPI analysis.These key genes are mainly enriched in ECM-receptor interaction,focal adhesion and protein digestion and absorption.CIBERSORT analysis showed that the infiltration ratio of M0 and M1 macrophages were higher in CAVD patients(P < 0.05);3.Age,proportion of hypertension,systolic blood pressure,aortic root diameter and left atrial diameter in AR group were larger,while height,weight,body surface area and aortic valvular opening were smaller,the differences were statistically significant(P < 0.05).Multivariate Logistic regression showed that age(OR=7.347,95%CI: 4.429-12.187,P < 0.001)and aortic root diameter(OR=2.025,95%CI: 1.338-3.065,P=0.001)were independent risk factors for mild AR.Height(OR=0.530,95%CI: 0.347-0.809,P=0.003)was an independent protective factor for mild AR;4.Through data mining and analysis,there were 22 common DEGs in AR and AD,including 14 up-regulated genes and 8 down-regulated genes.Common DEGs through GO analysis enriched in 64 biological processes such as regulation of positive chemotaxis,regulation of leukocyte cell-cell adhesion,cell-substrate adhesion,30 cell components such as collagen-containing extracellular matrix,fibrillar collagen trimer and banded collagen fibril,and 6 molecular functions such as MHC class II receptor activity,MHC class II protein complex binding and integrin binding.KEGG analysis showed that DEGs was mainly enriched in 10 pathways such as intestinal immune network for Ig A production,rheumatoid arthritis and leukocyte cell transendothelial migration.Ten key genes of AR and AD(THY1,COL1A1,VCAM1,CXCL12,LUM,LYVE1,ANGPT2,TIMP4,SFRP4 and MXRA5)were screened out by PPI analysis.Conclusion:1.The opening and closing function has been restricted in calcified aortic valve,which may have an impact on the structure and function of the heart and thus contribute to the development of cardiovascular diseases such as heart failure and atrial fibrillation.2.FN1,MMP9,COL3A1,SPP1,COL4A2,THBS2,COL5A2,COL5A1,COL4A1 and IGF1 are key genes in the progress of CAVD.The occurrence and development of CAVD are closely related to extracellular matrix remodeling and macrophage infiltration.Extracellular matrix regulation genes may be used as biomarkers for early CAVD and targets for prevention and treatment of CAVD;3.Aortic root dilation may be an important cause of early AR.THY1,COL1A1,VCAM1,CXCL12,LUM,LYVE1,ANGPT2,TIMP4,SFRP4 and MXRA5 are common key genes of AR and AD,and early intervention may prevent AD,then delay the occurrence and development of AR directly or indirectly.