Expressions And Significances Of Metastin And MMP-9 In The Nude Mice Endometriosis Model

The incidence rate of endometriosis is increasing with unknown mechanism and special pathology. In the development of endometriosis, typical endometrial structures are destroyed, which make the molecular study of endometriosis difficult and result in different conclusions. Although Sampon's theory has already been accepted, shed retrograde endometrial tissues are popular in reproductive women. So the invasive and metastatic growth of endometriotic lesions maybe essential steps in the pathogenesis of endometriosis. Based on the establishment of nude mice endometriosis model, we detected the gene and protein expressions of Metastin and MMP-9 in the endometriotic lesions acquired from nude mice killed at different times, and discussed the interaction between them.MethodsNormal human late secretory endometrium was put into the abdominal and pelvic cavity of nude nice to establish nude mice endometriosis model. Nude mice were killed at 5d, 10d, 15d and 30d, respectively, for obtaining the ec-topic growth endometrium. The normal human late secretory endometrium was as control.Reverse transcript polymerase chain reaction ( RT-PCR) and immunohisto-chemistry (SP) methods were utilized to examine the mRNA and protein expressions of Metastin and MMP-9.ResultsAll the transplants could be rediscovered in the pelvic and abdominal cavity of mice. Sites of implantation of the endometrial fragments were preferentiallythe peritoneum, the adipose fat surrounding bladder and the gut.On day 5, when the mice were killed, attachments were found in all cases and the macroscopic appearance of the endometriotic lesions were similar with the endometrium but slightly hard, which could be drown down by ophthalmolog-ic forceps. On day 10, the lesions became harder and tighter with the tissues of mice. On day 15, the endometriotic lesions and the tissues of mice were fused, which could not be detached. The guts of mice were a little stiff and adhesion. On day 30, the endometriotic lesions and the tissues of mice were more obviously fused. The surface of lesion was smooth and slightly protruded. The lesions atrophied and seemed smaller. The lesions showed more severe adhesions.5d, 10d and 15d groups expressed lower level of Metastin than control group ( P < 0. 05) ; and 30d group had no difference with the control group ( P > 0.05). However, 5d , 10d , 15d and 30d groups expressed higher level of MMP-9 than control group (P <0. 05) ; 15d group expressed highest among all the groups (P<0.05). In addition, the negative correlation was observed between Metastin mRNA and MMP-9 mRNA (r= -0.575, P<0.01).The positive rates of Metastin protein in progressive phase group (5d, 10d and 15d) and late phase group (30d) were 29.2% and 75% , which were lower than the control group 100% (P <0.05) ; The positive rates of MMP-9 protein in progressive phase group and late phase group were 87.5% and 75% , which were higher than the control group 30%.Conclusions1 Using nude mice endometriosis model, we can obtain endometriotic lesions from different times and different growth phases, which provide a better way to study human endometriosis.2 The expressions of Metastin gene and protein were all decreased in nude mice endometriotic lesions than normal endometrium, especially in 5d, lOd and 15d groups.3 The expressions of MMP-9 gene and protein were all increased in nude mice endometriotic lesions than normal endometrium.4 The decreased expression of Metastin and the increased expression of MMP-9 may be involved in the invasion and metastasis of endometriosis and they may play an important role in the genesis and development of endometriosis.