title: Mesenchymal stem cells overexpressing hepatocyte growth factor (HGF) inhibit collagen deposit and improve bladder function in rat model of bladder outlet obstruction.
abstract: Bladder outlet obstruction (BOO) caused by collagen deposit is one of the most common problems in elderly male. This study was performed to examine the capability of human mesenchymal stem cells (MSCs) overexpressing hepatocyte growth factor (HGF) to inhibit collagen deposition in rat  model of bladder outlet obstruction (BOO). HGF is known for its antifibrotic effect and the most promising agent for treating bladder fibrosis. BM3.B10 stable immortalized human MSC line (B10) was transduced to encode human HGF with a retroviral vector was prepared (B10.HGF). Two weeks after  the onset of BOO, B10, and B10.HGF cells were injected into the rat's bladder wall. After 4 weeks, bladder tissues were harvested and Masson's trichrome staining was performed. Transgene expression in HGF-expressing B10 cells was demonstrated by reverse transcriptase polymerase chain reaction  and immunohistochemical staining, and the high levels of HGF secreted by B10.HGF cells was confirmed by ELISA. The mean bladder weight in BOO rats was 5.8 times of the normal controls, while in animals grafted with B10.HGF cells, the weight was down to four times of the control [90.2 ±  1.6 (control), 89.9 ± 2.8 (sham), 527.9 ± 150.9 (BOO), 447.7 ± 41.0 (BOO + B10), and 362.7 ± 113.2 (BOO + B10.HGF)]. The mean percentage of collagen area increased in BOO rats, while in the animals transplanted with B10.HGF cells, the collagen area decreased to  the normal control level [12.2 ± 1.3, (control), 12.8 ± 1.1 (sham), 26.6 ± 2.7 (BOO), 19.9 ± 6.0 (BOO + B10), and 13.3 ± 2.1 (BOO + B10.HGF)]. The expression of collagen and TGF-b protein increased after BOO, while the expression of HGF and c-met protein  increased in the group with B10.HGF transplantation after BOO. Intercontraction interval decreased after BOO, but it recovered after B10.HGF transplantation. Maximal voiding pressure (MVP) increased after BOO, and it recovered to levels of the normal control after transplantation of B10.HGF  cells. Residual urine volume (RU) increased after BOO, but the RU increase was not reversed by transplantation of B10.HGF cells. Human MSCs overexpressing HGF inhibited collagen deposition and improved cystometric parameters in bladder outlet obstruction of rats. The present study indicates  that transplantation of MSCs modified to overexpress HGF could serve as a novel therapeutic strategy against bladder fibrosis in patients with bladder outlet obstruction.
authors.affiliation: Department of Urology, Soonchunhyang University School of Medicine, Seoul, South Korea.
authors.forename: Yun Seob
authors.initials: YS
authors.lastname: Song
authors.forename: Hong Jun
authors.initials: HJ
authors.lastname: Lee
authors.forename: Seung Hwan
authors.initials: SH
authors.lastname: Doo
authors.forename: Sun Ju
authors.initials: SJ
authors.lastname: Lee
authors.forename: Inja
authors.initials: I
authors.lastname: Lim
authors.forename: Kyu-Tae
authors.initials: KT
authors.lastname: Chang
authors.forename: Seung U
authors.initials: SU
authors.lastname: Kim
mesh_terms: D000818:Animals; D001835:Body Weight; D002478:Cells, Cultured; D003094:Collagen / Q000378:metabolism*; D004195:Disease Models, Animal; D017228:Hepatocyte Growth Factor / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D008297:Male; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000378:metabolism*; D019859:Proto-Oncogene Proteins c-met / Q000378:metabolism; D051381:Rats; D016212:Transforming Growth Factor beta / Q000378:metabolism; D001743:Urinary Bladder / Q000378:metabolism; D001745:Urinary Bladder Diseases / Q000378:metabolism / Q000503:physiopathology* / Q000628:therapy; D001748:Urinary Bladder Neck Obstruction / Q000378:metabolism / Q000503:physiopathology* / Q000628:therapy
chemical_list: D016212:Transforming Growth Factor beta; D017228:Hepatocyte Growth Factor; D003094:Collagen; D019859:Proto-Oncogene Proteins c-met