The Value Of Galectin-3 As A Urinary Diagnostic Maker For Interstitial Cystitis

Objective:To investigate the value of Galectin-3(Gal-3)as a diagnostic maker for Interstitial Cystitis/Bladder Pain Syndrome(IC/BPS),by detecting the expression of Gal-3 in the urine of established rat model of IC/BPS.Methods:1.Establishment of IC/BPS rat model:SD female rats were divided into control group(blank control group,n=10,bladder perfused with saline),experimental group 1(IC/BPS group,n=20,bladder perfused with protamine sulfate and lipopolysaccharide solution)and experimental group 2(inhibitor group,n=10,on the basis of the experimental group 1 to add modified citrus pectin solution).After 1 week,urine was collected from all three groups of rats for 24 hours and executed them to collect bladder tissue.2.To determine the success of rat model interstitial cystitis,observe the pathological characteristics of bladder tissue changes of the IC/BPS animal models by HE staining.3.Toluidine blue O staining was performed to detect the number of mast cells and degranulated mast cells in bladder tissues of each group.4.The Masson staining method was used to observe the changes of collagen fibers and muscle fibers in bladder tissues of the IC/BPS animal model.5.Immunohistochemical method was used to detect the expression level of Gal-3 in bladder tissue of each group.6.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentration of Gal-3 in the urine of each group of IC/BPS animal model.Results:1.HE staining showed no damage to the mucosa and submucosa layer of the bladder in the control group,no thinning of the mucosa,and only a small amount of inflammatory cell infiltration was seen.In the IC/BPS group,significant damage to the bladder mucosa layer was seen,with thinning of the mucosal layer,significant lymphocyte and mast cell infiltration.This is consistent with the pathological diagnostic criteria for IC/BPS and in line with the classical IC/BPS pathology.2.Toluidine blue O staining showed that the number of mast cells under the bladder mucosa was significantly increased in IC/BPS group(7.22±2.458),and a large number of degranulated mast cells were seen.While only a small number of mast cells(2.67±1.614)were observed in control group,and no degranulated mast cells appeared.The difference was statistically significant(t value was 6.061,P<0.05).3.Masson staining indicated that the bladder mucosa tissue in the IC/BPS group showed significant collagen fiber and muscle fiber hyperplasia,and collagen volume fraction was 48.43%±11.45%,compared with 27.53%±8.77%in the control group,with a significant difference(P<0.001).The inhibitor group was 26.33%±12.29%,with no statistically different from the control group(P=0.553).4.Immunohistochemical staining indicated that positive reactive cells located on the cell membrane could be seen in the IC/BPS group.The mean optical density was 0.129±0.032 in the IC/BPS group and0.049±0.014 in the control group,the difference between the two groups was statistically significant(P<0.05).And the mean optical density was0.058±0.022 in the inhibitor group,which was no statistically different from the control group.The expression of Gal-3 in the bladder tissues of the three groups showed a significant positive correlation with CVF(r_s=0.7155,P<0.0001).5.The enzyme-linked immunosorbent assay showed that the concentration of Gal-3 in the urine of rats in IC/BPS group was(13.92±5.27)pg/ml,compared with(9.16±3.30)pg/ml in the control group,which was significantly higher in the IC/BPS group(P<0.05).The concentration of Gal-3 in the urine of the inhibitor group was(8.50±6.36)pg/ml,which was significantly lower than that in the IC/BPS group(P<0.05).Conclusions:1.Bladder perfusion of protamine sulfate and lipopolysaccharide solution can successfully induce interstitial cystitis model in rats,relying on bladder-centered theory.2.Galectin-3 expression was significantly increased in bladder tissue of an animal model of interstitial cystitis,and its increased expression showed a moderate positive correlation with the degree of bladder fibrosis.3.The expression levels of Gal-3 were significantly higher in the urine of rats in the IC/BPS group,which suggesting that the detection of Gal-3 level in urine is expected to be a new marker for the diagnosis and prognosis assessment of IC/BPS.