Decreased Expression Of CXCL5 Is Associated With Intrauterine Adhesions In Rat Models And Humans

Background and objective: In recent years,with the increase in the number of intrauterine operations such as abortion surgery,the incidence of intrauterine adhesion(IUA)has also increased year by year.At present,the mechanism of the occurrence of IUA has not been fully elucidated,but a large number of studies have found that inflammatory cytokines are involved in the formation of IUA.Chemokine(C-X-C motif)ligand 5(CXCL5)acts as an inflammatory chemokine and has a strong chemotactic effect on neutrophils,and plays an important role in the formation and development of inflammation.However,whether there is a correlation between CXCL5 and adhesion formation and fibrosis in IUA has not been reported yet.Therefore,this study investigated the expression of CXCL5 in the IUA rat model and human intrauterine adhesion tissue,and explored whether there is a correlation between the expression of CXCL5 in the rat model of intrauterine adhesion and human intrauterine adhesions,for further study of CXCL5.New research directions and targets are provided in the mechanism of endometrial fibrosis and intrauterine adhesion formation.Methods: 1.Animal experiment Eight-week-old adult female SD rats were used as the research object,and the rat model of intrauterine adhesion was prepared by phenol cement method.Forty rats were randomly divided into three groups: the IUA group,the sham operation group,and the normal group.Fourteen days after surgery,the rats were sacrificed and the tissues were embedded in standard paraffin to prepare 5 ?m series sections.The animal experimental materials were analyzed by HE staining,Masson staining and immunohistochemistry(IHC).2.The human endometrial adhesion tissue of the IUA group was obtained from 6 cases of hysteroscopy confirmed by intrauterine adhesion in the university affiliated hospital,and the control group was taken from the normal endometrium of 6 cases of secondary infertility.The expression of CXCL5 m RNA and protein in endometrial tissues was detected by real-time PCR and Western blot in human endometrial tissues.Results: 1.In the IUA rat model,the uterine cavity was significantly narrowed and the degree of adhesion was deepened in the morphological and endometrial morphology of the IUA group compared with the normal group and the sham operation group.HE staining showed that compared with the normal group and the sham operation group,the number of glands in the IUA model group was significantly reduced,the gland was fragmented and dissolved,and it was surrounded by a large number of blue-stained neutrophils,and macrophages were also found.And plasma cells are replaced by collagen fibers.Masson staining showed that the submucosal tissue of the normal group was mildly blue-stained,and the degree of blue staining in the submucosal tissue of the sham operation group was similar to that of the normal group.Compared with the normal group and the sham operation group,the blue staining area of the submucosal tissue of the endometrium was significantly increased in the IUA group,and the degree of blue staining was significantly deepened.The results of IHC test showed that CXCL5 staining was strongly positive in the endometrium of normal and sham-operated rats,and the expression was mainly in the cytoplasm of glandular epithelial cells and interstitial cells,while the staining of CXCL5 in IUA group was low.There was no expression or no expression,and the difference was statistically significant(p < 0.01).2.Human endometrial tissue was detected by real-time PCR.The m RNA expression level of CXCL5 in the IUA group was significantly lower than that in the control group(p < 0.01).Western bolt test showed that the expression of CXCL5 protein in the IUA group was significantly lower than that in the control group(p < 0.05).Conclusions:1.The expression level of CXCL5 was correlated with the degree of intrauterine adhesion in rats,suggesting that CXCL5 may be involved in the development of intrauterine adhesions in rats.2.The expression level of CXCL5 in the endometrium of IUA patients was significantly lower than that in normal human endometrium,suggesting that CXCL5 may play a key role in promoting endometrial repair and preventing endometrial fibrosis.