Expression and Potential Role of MMP-9 in Intrauterine Adhesion.

Congqing Li,Lin Cong,Wenyan Wang,Shiying Sun,Youjiang Xu,Ziang Fang,Young-Su Yi

doi:10.1155/2021/6676510

Abstract

Objective Intrauterine adhesions affect menstruation and fertility, and endometrial fibrosis is the final manifestation of IUA. MMP-9 is closely related to fibrosis. The purpose of the study was to assess the role of MMP-9 in intrauterine adhesion (IUA) in rats and patients. Methods 40 rats and 24 women were enrolled in this study. 40 rats were randomly divided into 3 groups: IUA group (n = 20), sham group (n = 10), and control group (n = 10). Rat IUA models were established by intrauterine mechanical and chemical injured. In this study, 12 patients of intrauterine adhesions were detected and underwent TCRA (transcervical resection of adhesion) surgery, and endometrial tissue specimens were obtained during operation. One month later, an office hysteroscopy procedure was performed, and endometrial tissue specimens were obtained during operation again (postoperative group). A group of 12 normal age-matched control individuals served as controls underwent hysteroscopy and endometrial sampling. We used immunohistochemistry to detect MMP-9 expressions in rats and human endometrial tissues and to detect MMP-9 protein levels by Western blotting. In addition, we detected mRNA expression levels with qRT-PCR. Results The expression of MMP-9 in the IUA rats was reduced compared with that in the sham group and Ctrl group (P < 0.05), and the expression of MMP-9 was also reduced in the IUA patients compared with that in the Ctrl group (P < 0.05). The mRNA levels of MMP-9 in the endometrium reflected similar results (P < 0.05). The MMP-9 clearly increased even in the endometrium after TCRA surgery (P < 0.05). Conclusion Our study suggests that MMP-9 may play an important role in IUA. In the future, more in-depth research should be conducted on MMP-9.

Highlights

Intrauterine adhesion (IUA) is a condition that was identified more than a century ago [1]
We aimed to investigate whether matrix metalloproteinases (MMPs)-9 may be involved in fibrosis in IUA
We evaluated the potential role of MMP-9 in fibrosis in IUA by measuring the expression of MMP-9 in endometrial tissues

Summary

Introduction

Intrauterine adhesion (IUA) is a condition that was identified more than a century ago [1]. IUA is a very common problem encountered in clinical practice and is the main cause of menstrual volume reduction, infertility, and recurrent abortion. Injury is one of the direct causes of uterine cavity adhesion, and endometrial fibrosis is the final manifestation of IUA [2]. During the healing process of normal wounds, the deposition of extracellular matrix (ECM) leads to the occurrence and development of tissue fibrosis. The persistence of ECM components and the reduced deposition or degradation of the extracellular matrix may be the main causes of fibrosis [3]. Fibrosis involves the deposition of ECM proteins and related molecules/factors that crosslink various ECM elements, the hydrolysis of ECM proteins, and the enzymatic degradation of ECM. MMPs play a key role in the balance between fibrosis and antifibrosis; when fibrosis and antifibrosis are out of balance, and the degradation of the extracellular

Methods

Results

Conclusion