Clinical Study Of Serum Amino Acid Metabolism In Patients With Different Pathological Types Of Colorectal Polyps

Objective:Colorectal polyps are common diseases of the digestive tract,and whose incidence have gradually increased in recent years.Most sporadic colorectal cancer develops from it.At present,the diagnosis of colorectal polyps mainly relies on colonoscopy combined with histopathological examination,which is not only expensive,but also invasive,and has the risk of complications such as bleeding and perforation,so it is difficult to be used for general examination.Metabonomics provides the possibility of understanding disease status and screening potential biomarkers through the overall assessment of endogenous small molecules in the body.This study aims to explore the differences of serum amino acid metabolism between healthy people without polyps and patients with different pathological types of colorectal polyps,and to find the amino acids related to the occurrence of colorectal polyps,so as to find the early diagnostic markers and predict the direction of disease progression,and provide new clinical diagnosis and treatment ideas for the early detection and early intervention of colorectal polyp canceration.Methods:According to the inclusion and exclusion criteria,17 patients with colorectal polyps were strictly screened out.According to the degree of intraepithelial neoplasia,5 cases were in the non-intraepithelial neoplasia group,8 cases were in the low-grade intraepithelial neoplasia group,and 4 cases were in the high-grade intraepithelial neoplasia group.Meanwhile,5 cases were in the age-and gender-matched non-polyp control group.The amino acid metabolic profiles of serum samples were analyzed by liquid chromatography-mass spectrometry.Results:1.A total of 14 amino acids were detected by liquid chromatography-mass spectrometry,which were phenylalanine,glutamic acid,alanine,methionine,tyrosine,isoleucine,arginine,proline,valine,glutamine,leucine,histidine,lysine,tryptophan.2.In the comparison between the control group and the polyp groups with three different pathological types,there were differences in phenylalanine and glutamate among the groups(P<0.05),and they gradually increased with the progression of the disease.Phenylalanine,glutamate and alanine were potential biomarkers.Principal component analysis,partial least-square discriminant analysis and cluster analysis showed that there were certain differences between the control group and the group without intraepithelial neoplasia,the low-grade intraepithelial neoplasia group and the high-grade intraepithelial neoplasia group,but the separation trend was not obvious,and the patients with different pathological types of polyps could not be distinguished between groups.3.In the comparison between the control group and the polyp group,there were significant differences in 9 amino acids in the serum samples of the two groups(P<0.05),among which the contents of histidine,proline,glutamic acid,glutamine,isoleucine and valine in the polyp group increased,while the contents of alanine,tyrosine and methionine in the polyp group decreased.Principal component analysis could not distinguish the two groups.Partial least squares discriminant analysis and cluster analysis could roughly separate the control group from the polyp group,but further expansion of sample size was needed for verification.The success rate of polyp group was predicted to be 82.4%.Glutamate was the main metabolite of difference.Conclusion:Serum amino acid metabolism in patients with colorectal polyps has certain changes compared with healthy people without polyps.Although the difference in serum amino acid metabolism cannot be used to accurately distinguish patients with different pathological types of polyps,it can be used to distinguish patients in the control group and the polyp group.Phenylalanine,glutamate and alanine may be important biomarkers for the screening,diagnosis and treatment of colorectal polyps.