The clinical application value of the biomarkers based on autophagy screening in the diagnosis and monitoring of inflammatory bowel disease in pediatric patients

Abstract

Inflammatory bowel diseases (IBD) are immune-mediated disorders of children and adults. Autophagy dysfunction has been linked to IBD pathology, and we screened and evaluated the potential biomarkers for pediatric IBD diagnosis and activity evaluation. The autophagy gene expression matrix of IBD samples was obtained via GeneCards and GEO databases. Significant differentially expressed genes were obtained using the R language "limma" package, followed by KEGG enrichment analysis using the "clusterProfile" package. Totally, 95 pediatric IBD patients and 44 controls were selected from Beijing Children's Hospital, with IBD subjects divided into the IBD-Remission and IBD-Activity groups. Peripheral blood autophagy-related gene levels in pediatric IBD patients were determined by RT-qPCR. Autophagy genes that were independently correlated with pediatric IBD occurrence and activity were screened, with their value for diagnosing and monitoring the activity of pediatric IBD assessed. OPTN, GABARAPL2, FKBP8, BNIP3L, and BCL2L1 were obtained as the autophagy-related genes. FKBP8 and BCL2L1 mRNA expression levels were elevated in IBD patients. BCL2L1 was an independent risk factor (IRF) for pediatric IBD occurrence. Peripheral blood BCL2L1 > 0.75 had high auxiliary diagnostic value for pediatric IBD occurrence. BCL2L1 and GABARAPL2 were higher in the IBD-Activity group than in the IBD-Remission group. Peripheral blood BCL2L1 was an IRF for pediatric IBD activity. Peripheral blood BCL2L1 > 1.96 had high auxiliary predictive value for pediatric IBD activity.

Conclusion: BCL2L1 was an IRF for the occurrence and disease activity of pediatric IBD and had high clinical application value in assisting pediatric IBD diagnosis and predicting disease activity.

What is known: • Autophagy dysfunction is associated with IBD. • No research reports on the clinical application of autophagy-related biomarkers in the diagnosis and activity monitoring of IBD.

What is new: • BCL2L1 was an IRF for the occurrence and disease activity of pediatric IBD. • BCL2L1 had high clinical application value in assisting pediatric IBD diagnosis and predicting disease activity.

Keywords: Activity; Autophagy; BCL2L1; Biomarkers; Children; FKBP8; GABARAPL2; Inflammatory bowel disease.

Fig. 1

Screening of differentially expressed genes related to autophagy in pediatric IBD. A Differential gene volcano diagram of chip GSE119600, with the horizontal axis representing -log10 p.value and the vertical axis representing logFC. The red dots indicated significantly highly expressed genes in IBD samples and green dots noted markedly poorly expressed genes in IBD samples; B differential gene KEGG enrichment analysis bubble chart, where the horizontal axis represented the gene ratio, the vertical axis represented the KEGG entries, and the upper right bubble color represented enrichment level

Fig. 2

Verification of differential expression of mitophagy-related genes in the peripheral blood in IBD pediatric patients. RT-qPCR to determine the expression levels of A OPTN, B BNIP3L, C BCL2L1, D GABARAPL2, and E FKBP8 in pediatric patients with IBD. The data were expressed as median (interquartile range), and the Wilcoxon test was used for comparisons between two groups. ns P > 0.05, ** P < 0.05

Fig. 3

Correlation analyses of BCL2L1 and FKBP8 with clinical indicators of IBD. The Spearman analysis was used to analyze the correlations of BCL2L1 with A PLT, B ESR, C FIB, D CRP, and E FC, as well as the correlations of FKBP8 with F PLT, G ESR, H FIB, I CRP, and J FC

Fig. 4

BCL2L1 had high auxiliary diagnostic value for pediatric IBD. The ROC curve analysis on the predictive value of CRP, FC, and the mitophagy-related gene BCL2L1 for the occurrence of IBD in pediatric patients

Fig. 5

Differential expression analysis of mitophagy-related genes in the peripheral blood of pediatric patients with active IBD. RT-qPCR was used to measure the expression levels of A OPTN, B BNIP3L, C BCL2L1, D GABARAPL2, and E FKBP8 in the peripheral blood of pediatric patients with remission-stage and active-stage IBD. The data were expressed as median (interquartile range), and the Wilcoxon test was used for comparisons between two groups. ns P > 0.05, ** P < 0.05

Fig. 6

Correlation analyses of BCL2L1 and GABARAPL2 with ESR. The Spearman analysis was utilized to analyze the correlations of A BCL2L1 and B GABARAPL2 with ESR

Fig. 7

BCL2L1 had high auxiliary predictive value for the activity of IBD in pediatric patients. The ROC curve analysis on the predictive value of BCL2L1 for the activity of IBD in pediatric patients