Metabolic Characterization Of Hypertrophic Cardiomyopathy And Mutation Gene Screening

Objectives:(1)To analyze the clinical characteristics of hypertrophic cardiomyopathy(HCM)patients and to screen the disease-causing gene mutation sites in patients with familial HCM and their family members,and conducting planned follow-up;(2)To analyze the plasma metabolic characteristics and differential metabolites between hypertrophic cardiomyopathy patients by using ultra-high performance liquid chromatography-high resolution mass spectrometry(UPLC-HRMS),additionally,potential metabolic pathways was analyzed to increase the knowledge and understanding of diseases,and then,guiding clinical diagnosis,treatment and prognosis.Methods: We recruited total 113 people,including 42 HCM patients hospitalized in the Department of Cardiovascular Medicine,Yunnan First People’s Hospital from January2021 to December 2022,28 family members with familial HCM and 53 normal healthy patients from the physical examination center,and collected the clinical data as well as blood samples.Patients with familial HCM and their family members underwent whole exome sequencing and Sanger sequencing to screen and verify the mutation site of the diseasecausing gene.Plasma metabolites in all the above populations were tested in UPLC-HRMS by non-targeted metabolomics.The Metabo Analyst 5.0 website(https://www.metaboanalyst.ca/)is being used to establish model,to screen potential metabolite,and to analyze metabolic pathways in HCM patients with different classifications and different pathogenic gene mutations.Results: Whole-exome sequencing and Sanger sequencing were performed on 10 patients with familial HCM and 28 family members,and 3 cases with MYBPC3 c.G1591A(G531R)were screened in G family,and 4 cases with SCN5 A c.A1673 G were screened in Z family(H558R),and 6 cases with TNNI3 c.G557A(Arg186Gl)were screened in N family.Basing on the UPLC-HRMS to establish non-targeted metabolomics,112 metabolites were qualitatively identified in plasma samples,and 104 metabolites were quantified in combination with the internal standard method.Principal component analysis and partial least squares-discriminant analysis were used to construct a classification model.Variable importance in projection(VIP)> 1.5 and corrected t-test false discovery rate(FDR)< 0.05 were used as screening criteria.HCM patients group and healthy controls,familial HCM group and sporadic HCM group,TNNI3 mutation group and the healthy family member group without TNNI3 mutation,as well as TNNI3 mutation group and SCN5 A mutation group was compared respectively.17,14,11 and 6 differential metabolites were screened respectively,and the screened significantly different metabolites were analyzed by metabolic pathway analysis,and it was found that all of them were closely related to amino acid metabolic pathways.Conclusions: 1.There are disorders of amino acid,organic acid and lipid metabolites in HCM patients comparing with healthy control,and the disorder of amino acid metabolism is dominant.It is speculated that the disorder of amino acid metabolism may be closely related to the pathophysiology of HCM,and the intervention of amino acid metabolism may be a potential way to delay the clinical progression of the disease and improve the prognosis.2.The metabolic characteristics of patients with familial HCM and sporadic HCM are not completely the same,which may be potentially related to genetic factors.3.Different metabolic profiles can be observed between patients with or without carrying disease-causing mutations and between patients with different disease-causing mutations,and there is a certain classification trend,and suggesting that there is genetic clustering of metabolite level changes.4.Metabolic pathway analysis showed that amino acid metabolic pathways were the main disorder in patients with HCM,and the disturbed amino acid pathways were not completely the same in different groups.