Expressions And Significance Of Elastin And Fibulin-5 In Cardinal Ligament And Anterior Vaginal Wall Tissue Of Pelvic Floor Dysfunction

Pelvic organ prolapse(POP) is a common disease that affects seriously the quality of life of old age women.However,the mechanisms by which pregnancy and parturition lead to failure of pelvic organ support are not known.Recently,it was reported that pelvic organ prolapse is significantly correlation with the elasticity, tenacity and functionalis of fibromuscular connective tissue.Elastin is a major component of extracellular matrix.Fibulin-5 is crucial for elastin assembly and is believed to act as a bridge between cells and tropoelastin for effective cross-linking and assembly of tropoelastin into mature elastic fibers.The aim of the this study is to explore the relationship between Fibulin-5 and elastin expression in the pathogenesis of pelvic organ prolapse.Materials and methods1.Tissue samples and groupsSixty-eight POP and sixteen NON-POP cardinal ligament and paries anterior vaginase tissue specimens and were obtained from patients underwent surgical resection at Shengjing Hospital of China Medical University between 2006 and 2008. All the samples were fixed by formalin and embedded in paraffin.2.ReagentsThe primary antibody anti-human Fibulin-5 mouse monoclonal antibody and anti-human elastic fiber rabbit polyclonal antibody were both produced in Santa Cruz Corporation.S-P kit were purchased from Zhongshan Biotechnology Corporation. DAB agent kit and horseradish peroxidase labeled goat-anti-mouse IgG were bought from Beijing Zhongshan Golden Bridge Biotechnology Corporation.3.Immunohistochemistry Immunohistochemical staining was performed by the streptavidin-peroxidase(S-P) method.The sections were deparaffmized,water processed,treated by high tempreture to expose antigen and incubated with primary antibody at 4.0℃overnight. The color was developed with diaminobenzidine and the section were couterstained with harmatoxylin.For the nonspecific reagent control,the primary antibodies were replaced by PBS.The expression of Fibulin-5 or elastin by staining was graded for the percentage of immunoreactive extracellular matrix.Elect random 10 areas at 200 magnification,the case which the masculine percentage esceeded 10%was judged as positive expression.4.Statistical analysis.The statistical package SPSS13.0 was used for all analyses.The chi-square test was used to determine the correlation between Fibulin-5 or elastin expression and clinicopathological factors,The relationship between Fibulin-5 and elastin was analised by Spearman test.Values of P＜0.05 were considered statistically significant.Results1.The relationship between the expression of Fibulin-5 in cardinal ligament and anterior vaginal wall and pathological features.Fibulin-5 protein positive expression rate in POP group anterior vaginal wall and cardinal ligament was found 17.24%(10/58 ),28.30%(15/53)respectively,the positive rate were significantly decreased in POP group compared to NON-POP group tissues (80%,50%respectively,P＜0.05).Patients with lower Fibulin-5 expression had advanced stage of POP(Ⅰ+ⅡversusⅢ+Ⅳ,P=0.035,0.020),accompany stress urinary incontinence(P=0.036,0.016),Vaginal parity(P=0.510,0.562).However,no statistical difference was found between the Fibulin-5 expression and the menopausal state.(P=0.236,0.185).2.Expression of elastic fiber and the relationship between the expression of elastin and pathological features.Elastin expression was significantly decreased in women with anterior vaginal wall prolapse compared to women without prolapse.The elastin expression level was correlated with the stage of POP(P=0.034,0.024).However,no statistical difference was found between the Elastin expression and Stress urinary incontinence(P=0.599,0.602),Vaginal parity(P=0.788,0.433) and the Menopausal state(P=0.695,0.707). 3.The relationship between the expression of Fibulin-5 and elastin.Co-expression of Fibulin-5 and elastin was 9 cases in cardinal ligament.Both negative expression of Fibulin-5 and elastin was 39 cases in cardinal ligament.A positive correlation was observed between the expression of Fibulin-5 and that of elastin(P=0.015).The same result was found in anterior vaginal wall(P=0.031).Conclusions1.Fibulin-5 and elastin protein expression were decreased in cardinal ligament and anterior vaginal wall in POP group compared to NON-POP group(P＜0.05).The expression of Fibulin-5 and elastin were correlated closely with stage of POP and frequency of Vaginal delivery.but had no relationship with Menopausal state.2.The expression of Fibulin-5 is positive associated with elastin in pelvic organ prolapse.Changes in Fibulin-5 and elastin expression may play a role in the development of pelvic organ prolapse.