Differentially Expressed Genes Correlated with Fibrosis in a Rat Model of Chronic Partial Bladder Outlet Obstruction

Chronic partial bladder outlet obstruction (PBOO) is a prevalent clinical problem that may result from multiple etiologies. PBOO may be a secondary condition to various anatomical and functional abnormalities. Bladder fibrosis is the worst outcome of PBOO. However, gene alterations and the mechanism of fibrosis development after PBOO onset are not clear. Therefore, we aimed to investigate gene expression alterations during chronic PBOO. A rat model of PBOO was established and validated by a significant increase in rat bladder weight. The bladder samples were further analyzed by microarray, and differentially expressed genes (DEGs) that are more related to PBOO compared with the control genes were selected. The data showed that 16 significantly upregulated mRNAs and 3 significantly downregulated mRNAs are involved in fibrosis. Moreover, 13 significantly upregulated mRNAs and 12 significantly downregulated mRNAs are related to TGFB signaling. Twenty-two significantly upregulated mRNAs and nine significantly downregulated mRNAs are related to the extracellular matrix. The genes with differential expressions greater than four-fold included Grem1, Thbs1, Col8a1, Itga5, Tnc, Lox, Timp1, Col4a1, Col4a2, Bhlhe40, Itga1, Tgfb3, and Gadd45b. The gene with a differential expression less than a quarter-fold was Thbs2. These findings show the potential roles of these genes in the physiology of PBOO.

Therapeutic effect of adipose stromal vascular fraction spheroids for partial bladder outlet obstruction induced underactive bladder

Background: Underactive bladder (UAB) is a common clinical problem but related research is rarely explored. As there are currently no effective therapies, the administration of adipose stromal vascular fraction (ad-SVF) provides a new potential method to treat underactive bladder. Methods: Male Sprague-Dawley rats were induced by partial bladder outlet obstruction (PBOO) for four weeks and randomly divided into three groups: rats treated with PBS (Sham group); rats administrated with ad-SVF (ad-SVF group) and rats performed with ad-SVF spheroids (ad-SVFsp group). After four weeks, urodynamic studies were performed to evaluate bladder functions and all rats were sacrificed for further studies.Results: We observed that the bladder functions and symptoms of UAB were significantly improved in the ad-SVFsp group than that in the Sham group and ad-SVF group. Meanwhile, our data showed that ad-SVF spheroids could remarkably promote angiogenesis, suppress cell apoptosis and stimulate cell proliferation in bladder tissue than that in the other two groups. Moreover, ad-SVF spheroids increased the expression levels of bFGF, HGF and VEGF-A than ad-SVF. IVIS Spectrum small-animal in vivo imaging system revealed that ad-SVF spheroids could increase the retention rate of transplanted cells in bladder tissue. Conclusions: Ad-SVF spheroids improved functions and symptoms of bladder induced by PBOO, which contributes to promote angiogenesis, suppress cell apoptosis and stimulate cell proliferation. Ad-SVF spheroids provide a potential treatment for the future patients with UAB.

Human Urine-derived Stem Cells Improve Partial Bladder Outlet Obstruction in Rats: Preliminary Data and microRNA-mRNA Expression Profile

Background: Partial bladder outlet obstruction (pBOO), a common urological disease, often results in bladder tissue inflammation and remodeling. Human urine-derived stem cells (USCs) have demonstrated therapeutic benefits in various organ injury models. We used a rat model of pBOO to investigate the effect of USCs on bladder function and to explore the miRNA and gene expression profiles in bladder tissue using RNA sequencing.Methods: In total, 18 rats were randomly and evenly assigned to the following three groups: a sham surgery group, a pBOO without USC therapy group, and a pBOO with USC therapy group (subjected to treatment with USCs six times every other week). All rats were subjected to routine urodynamic monitoring. Detrusor muscle strips were analyzed and pathophysiology was assessed. Finally, altered miRNA and mRNA expression profiles of bladder tissue were examined using RNA sequencing and bioinformatics analysis technology.Results: After USC treatment, urodynamic monitoring revealed elevated bladder compliance and maximal voiding pressure, declined end filling pressure and voided volume, and improved detrusor muscle contractility and carbachol sensitivity in pBOO rats. Histology and TUNEL assay revealed reduced collagen deposition and muscle cell apoptosis in bladder tissue. The differential expression of eight miRNAs in pBOO rats was reversed by USC treatment. Bioinformatics analysis helped identify miR-142 and miR-9a as the two largest nodes of differentially expressed miRNAs in the miRNA‑gene interaction network in the USC-treated group. The Kyoto Encyclopedia of Genes and Genomes analysis revealed enrichment of multiple significant pathways, including those involved in necroptosis and cytokine-cytokine receptor interactions.Conclusions: This is the first study to reveal the protective effect of USCs on bladder function and bladder remodeling in pBOO rats. The miRNA and mRNA expression levels differed in the bladder of pBOO rats with and without USC treatment. Although the mechanism underlying these effects has not been fully elucidated, necroptosis and cytokine-cytokine receptor interaction-related pathways may be involved.

miRNA-325-3p overexpression mitigates partial bladder outlet obstruction (PBOO) by regulating the TLR4/NF-κB(p65) pathway

IntroductionThe microRNA (miRNA) is a noncoding RNA that plays an important role in many diseases. Partial bladder outlet obstruction (PBOO) is a blockage between the outlet of the neck of the bladder and the external urethral orifice secondary to prostate hyperplasia and urethral stricture, and causative of morphological and functional abnormalities in the bladder. We examine the effects of miRNA-325-3p on PBOO and related mechanisms through an in-vitro study.Material and methodsPrimary BSMCs were extracted from SD rats and subjected to TGF-β1 stimulation to form a cell model of PBOO. Cell proliferation was measured by CCK-8 assay, and the gene and protein expressions were measured by RT-qPCR, western blot, and immunofluorescence. The correlation between miRNA-325-3p and ILK was analyzed through a double-luciferase target experiment.ResultsThe proliferation of BSMCs in the model group increased more significantly than in the normal group (P<0.001) with miRNA-325-3p repression, and led to the activation of ILK and the TLR4/NF-κB(p65) pathway as well as significant changes in the marker proteins. With miRNA-325-3p transfection, the rate of cell proliferation of the miRNA-325-3p group was significantly suppressed with ILK repression compared with that of the model group, and led to the suppression of TLR4/NF-κB(p65) activity and the regulation of protein expressions. However, the miRNA-325-3p treatment’s effects disappeared as ILK was supplemented. The double-luciferase experiment helped miRNA-325-3p target ILK in BSMCs.ConclusionsmiRNA-325-3p overexpression may play a key role in PBOO-induced cell proliferation by targeting ILK and suppressing the TLR4/NF-κB(p65) signaling pathway.

Human Urine-derived Stem Cells Improve Bladder Function After Partial Bladder Outlet Obstruction: Preliminary Data and the microRNA–mRNA Expression Profile of Bladder Tissue

Background: Partial bladder outlet obstruction (pBOO), a common urological disease, often results in bladder tissue inflammation and tissue remodeling. Human urine-derived stem cells (hUSCs) have shown therapeutic benefits in various organ injury models. We used a rat model to investigate the effect of hUSCs on bladder function in pBOO rats and explore the miRNA and gene expression profiles in bladder tissue using RNA-sequencing.Methods: In total, 18 rats were randomly and evenly assigned to three groups: a sham surgery group, a pBOO without USCs therapy group, and a pBOO with USCs therapy group (treated with hUSCs six times every other week). All rats were subjected to routine urodynamic monitoring. Detrusor muscle strips were evaluated and pathophysiology was assessed. Finally, altered miRNA and mRNA expression profiles of bladder tissue were examined using RNA-sequencing and bioinformatic analysis technology.Results: After USC treatment, urodynamic monitoring revealed elevated bladder compliance and maximal voiding pressure, declined end filling pressure and voided volume, and improved detrusor contractility and carbachol sensitivity in pBOO rats. Histology and TUNEL assay showed reduced collagen deposition and muscle cell apoptosis in bladder tissue. The differential expression of eight miRNAs in pBOO rats was reversed by USC treatment. Bioinformatic analysis identified miR-142 and miR-9a as the two largest nodes of differentially expressed miRNAs in the miRNA‑gene interaction network. The Kyoto Encyclopedia of Genes and Genomes analysis revealed enrichment of multiple significant pathways, including those involved in necroptosis and cytokine-cytokine receptor interactions.Conclusions: This is the first study to reveal the protective effect of hUSCs on bladder function and bladder remodeling in pBOO rats. The miRNA and mRNA expression levels differed in the bladder of pBOO rats with and without USC treatment. Although the mechanism underlying these effects have not been fully elucidated, necroptosis and cytokine-cytokine receptor interaction related pathways may be involved.

Metformin ameliorates bladder dysfunction in a rat model of partial bladder outlet obstruction

The present study in a rat model showed that oral administration of metformin alleviated inflammation following partial bladder outlet obstruction in the early phase and ameliorated bladder fibrosis as well as bladder dysfunction by long-term treatment. Our study indicated that metformin is a potential drug to inhibit bladder remodeling and alleviate bladder dysfunction. Clinical trials are needed to validate the effect of metformin on the bladder dysfunction and bladder fibrosis in the future.

Mesenchymal stem cells ameliorate partial bladder outlet obstruction-induced epithelial-mesenchymal transition type II independent of mast cell recruitment and degranulation

Introduction: Partial bladder outlet obstruction (pBOO) results in increased urinary storage pressure and significant morbidity. Increased pressure results in a sequence of programmed events: an initial inflammatory phase, smooth muscle hypertrophy, and fibrosis. Although epithelial-mesenchymal transition (EMT) and mast cell accumulation play intermediary roles in some fibrotic conditions, their role in pBOO has not yet been elucidated. Mesenchymal stem cell (MSC) therapy is emerging as a promising treatment for several conditions. It potently inhibits bladder deterioration after pBOO; however, its mechanism of action is insufficiently understood. Thus, we hypothesize that EMT type II pathway plays a significant role in pBOO, aided by the recruitment and activation of mast cells, and these are potently inhibited by MSCs. Methods: PBOO was surgically induced in female Sprague-Dawley rats and simultaneously treated with MSCs. Treatment effect was determined after two or four weeks, and compared to untreated controls. Immunohistochemistry was used to measure markers characteristic of EMT (vimentin, collagenase, and collagen). Whole and degranulated mast cell counts were also performed. Results: PBOO resulted in an increased expression of collagenase, vimentin, and collagen. Mast cell recruitment increased proportionately to the length of bladder obstruction. MSC treatment significantly mitigated the EMT type II response, but mast cell recruitment and degranulation were unaffected. Conclusions: Our results demonstrate the involvement of EMT type II in the pathophysiology of pBOO and confirm its mitigation with MSC treatment independent of mast cells response. The observations provide insight into the mechanism of action and have therapeutic ramifications.