Identification of potential modulators of intrauterine adhesion pathogenesis with RNA sequencing, histology and in vitro assays

Intrauterine adhesion (IUA), also referred to as intrauterine stenosis or synechiae, is a prevalent gynecological issue, which is characterized by the fusion of the walls of the intrauterine canal. However, the molecular changes during its pathogenesis are still unclear. In the present work, tissue samples from patients with IUA and normal endometrial tissues from healthy subjects were collected, and then RNA sequencing and bioinformatics analyses were performed to screen the differentially expressed genes (DEGs). Subsequently, immunohistochemistry was used for detecting the protein expression level of the representative genes including XDH, VNN1, CD36, and after transfection, enzyme-linked immunosorbent assay and Western blotting were used to evaluate their functions in regulating inflammatory response and the expression level of matrix metalloproteinases. It was revealed that multiple genes were dysregulated in the pathological tissues of patients with IUA, and these DEGs were associated with multiple biological processes and signal pathways including Hedgehog pathway. DEGs including XDH, VNN1, CD36 were also highly expressed in IUA tissues at protein level, and their expression levels correlated with the expression levels of inflammation mediators NLRP3 and STING. XHD, VNN1 and CD36 also promoted the expression and secretion of TNF-α, IL-1β and IL-6 in ishikawa cells, and up-regulated the expression level of MMP-2 and MMP-9. Collectively, our data suggested that Hedgehog signaling is a potential crucial pathway in IUA pathogenesis, and some DEGs contribute to endometrial fibrosis by regulating inflammatory response and matrix remodeling.