MP45-13 POST-OBSTRUCTIVE BLADDER SMOOTH MUSCLE REMODELING IS DEPENDENT ON BLADDER STEM CELLS

Abstract

You have accessJournal of UrologyBenign Prostatic Hyperplasia: Basic Research & Pathophysiology1 Apr 2018MP45-13 POST-OBSTRUCTIVE BLADDER SMOOTH MUSCLE REMODELING IS DEPENDENT ON BLADDER STEM CELLS Belinda Li, Megan Y. Devine, Nicholas M. Tassone, Robert W. Dettman, and Edward M. Gong Belinda LiBelinda Li More articles by this author , Megan Y. DevineMegan Y. Devine More articles by this author , Nicholas M. TassoneNicholas M. Tassone More articles by this author , Robert W. DettmanRobert W. Dettman More articles by this author , and Edward M. GongEdward M. Gong More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.1452AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Partial bladder outlet obstruction results from benign prostatic hypertrophy in men and posterior urethral valves in children, leading to detrusor remodeling and impaired function and compliance. A Sca-1+/CD34+ coexpressing mesenchymal stem cell population was previously identified in the stromal layer of the murine bladder which is altered after acute and partial outlet obstructions. We hypothesize that loss of Sca-1+ will inhibit the physiologic detrusor hypertrophy that occurs after obstruction leading to decreased compensatory function. METHODS 6-8 week-old male Sca-1 null mice and genetically unmodified (C57/BL6) mice both underwent surgical partial obstruction (PO) at the bladder neck. An additional cohort of Sca-1 null mice underwent sham surgery for comparison. Voiding stains on paper at 1, 2, and 4 weeks were analyzed for functional assessments of the bladder. Whole bladders were analyzed at 4 weeks by weight and distributed for histologic exam and RNA extraction. Bladder thickness and circumference were measured. Masson′s Trichome staining was used to calculate detrusor collagen to smooth muscle ratios and total smooth muscle content. RESULTS Comparisons were made between PO groups of Sca-1 null mice (Figure b) and C57/BL6 mice (Figure c), as well as between Sca-1 null mice who either underwent PO or sham surgery (Figure a). PO led to increased bladder circumference in Sca-1 null mice (2.06±0.42 cm) compared to the sham group (1.21±0.25 cm) (p=0.04). Mean bladder smooth muscle content in C57/BL6 mice was 0.83±0.09 compared to 0.67±0.10 in Sca-1 null mice (p=0.02). Sca-1 null sham mice had a bladder smooth muscle composition of 0.88±0.05 (p=0.02). Lower collagen-to-smooth muscle ratios were also found in the C57/BL6 group at 0.23±0.14 compared to 0.55±0.25 in Sca-1 null mice (p=0.03). Comparison graphs are shown in the Figure. CONCLUSIONS Our findings suggest that Sca-1+/CD34+ mesenchymal stem cells play a role in detrusor smooth muscle remodeling and hypertrophy after partial obstruction. Stem cell intact mice displayed increased bladder smooth muscle composition and decreased levels of collagen infiltration consistent with fibrosis compared to knockout comparisons. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e602 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Belinda Li More articles by this author Megan Y. Devine More articles by this author Nicholas M. Tassone More articles by this author Robert W. Dettman More articles by this author Edward M. Gong More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...