Recombinant insulin-like growth factor-1 activates satellite cells in the mouse urethral rhabdosphincter.

Background: The goal of this study is to demonstrate the efficacy of a new method for the treatment of urinary incontinence by stimulation of urethral rhabdosphincter satellite cells. We show that satellite cells do exist in the sphincter muscle of retired male mice breeders by staining for c-Met, a satellite cell specific protein. Once activated by recombinant mouse Insulin-like Growth Factor-1(rIgf-1), the satellite cells develop into muscle cells within the rhabdosphincter thereby potentially strengthening it.

Urinary diversion results in marked decreases in proliferation and apoptosis in fetal bladder.

Purpose: We sought to determine if bladder cycling is required for remodeling during fetal development.

Materials And Methods: For this study 5 fetal sheep bladders were harvested after 2 weeks of urinary diversion, initiated at approximately 90 days of gestation. Six unoperated sheep bladders of approximately 105 days of gestational age were used as controls.

Beta and gamma-sarcoglycans are decreased in the detrusor smooth muscle cells of the partially obstructed rabbit bladder.

Purpose: We evaluated and quantified the levels of sarcoglycans present in the detrusor muscle layer of rabbits with partial bladder outlet obstruction.

Materials And Methods: Rabbits underwent surgery, as previously described, to partially obstruct the urethra. One, 3, 7 and 14 days after obstruction the detrusor muscle layer was dissected free of the remaining bladder tissue and extracted with detergent to isolate the transmembrane components of the dystroglycan-glycoprotein complex.

Altered extracellular matrix expression in the diverted fetal sheep bladder.

Purpose: It is unclear whether filling and emptying are important to bladder development. We tested this in an experimental preparation.

Material And Methods: Urinary diversion was performed in 7 fetal lambs at 90 days of gestation and 6 unoperated fetal lambs served as controls.

Smooth muscle trans-membrane sarcoglycan complex in partial bladder outlet obstruction.

The urinary bladder experiences both distension and contraction as a part of the normal filling and emptying cycle. To empty properly, tension generated intracellularly in a smooth muscle cell must be smoothly and efficiently transferred across its sarcolemma to the basement membrane, which mediates its binding to both the extracellular matrix and to other cells. As a consequence of urethral obstruction, the bladder cannot generate appropriate force to contract the organ, thereby leading to inefficient emptying and associated sequelae.

Transforming growth factor-beta1-induced hypertrophy and matrix expression in human bladder smooth muscle cells.

Objectives: To determine whether transforming growth factor beta (TGF-beta) could activate hyperplasia, hypertrophy, and altered collagen expression in human detrusor smooth muscle cells (SMCs).

Methods: Human bladder SMCs were treated in vitro with TGF-beta1 and analyzed for changes in both proliferative and hypertrophic responses by cell number and volume measurements, as well as for alterations in extracellular matrix gene and protein expression by Northern blot and enzyme-linked immunosorbent assay.

Results: Proliferation of bladder SMCs was refractory to TGF-beta1, whereas the cells became hypertrophic upon TGF-beta1 treatment.

Mast cell chymase is a possible mediator of neurogenic bladder fibrosis.

Aims: Urinary bladders of patients with myelomeningocele, owing to spina bifida, are often functionally impaired, fibrotic organs. Common to this condition are repeated occurrences of bladder infection and inflammation. Since mast cells have been associated with a fibrogenic response in inflammatory conditions, we investigated the role of mast cell granule product, chymase, as a mediator of myleodysplastic bladder fibrosis.

Compression and tension: differential effects on matrix accumulation by periodontal ligament fibroblasts in vitro.

Human periodontal ligament fibroblasts were subjected to 10% cyclic equibiaxial tensional and compressive forces in vitro. Media supernatants were analyzed for changes in total protein, extracellular matrix proteins type I collagen and fibronectin, as well as MMP expression by gelatin zymography and Western blot. RNA analyses for changes in collagen, MMP-2, and TIMP-2 were carried out by either Real-time PCR and/or Northern blot.

Matrix synthesis by bladder smooth muscle cells is modulated by stretch frequency.

The bladder is a physically active organ that undergoes periodic stretching as a part of its normal function. To determine the role that stretching or mechanical deformation may play in altering the synthetic phenotype of bladder wall cells, a series of experiments were carried out to quantify several extracellular matrix (ECM) messenger ribonucleic acids (mRNAs) and their corresponding protein levels after mechanical challenge. Bladder smooth muscle cells were grown on distensible membranes in an apparatus that can reliably and reproducibly subject cells to well-characterized periods of mechanical stretching.

Correlation of P-cadherin and beta-catenin expression and phosphorylation with carcinogenesis in rat tongue cancer induced with 4-nitroquinoline 1-oxide.

Using biochemical and immunohistochemical techniques, we have investigated P-cadherin, beta-catenin, c-src and c-met protein expression, and phosphorylation of beta-catenin in a rat model of tongue cancer induced with 4-nitroquinoline 1-oxide. Six-week-old male Sprague-Dawley rats were given either normal drinking water (controls) or 50 ppm 4NQO solution as drinking water for 16 and 20 weeks. This treatment produced dysplasia and well-differentiated squamous cell cancer in rat tongues after 16 and 20 weeks, respectively.

Response of the fetal sheep bladder to urinary diversion.

Purpose: In adults urinary diversion results in bladder atrophy and a rapid decrease in contractile function. Little is known about the effects of urinary diversion on bladder development. In this regard we characterized the responses of fetal sheep bladder strips obtained from animals that underwent urinary diversion.

The transforming growth factor-beta-inducible matrix protein (beta)ig-h3 interacts with fibronectin.

Proper growth and development require the orderly synthesis and deposition of individual components of the extracellular matrix (ECM) into well ordered networks. Once formed, the ECM maintains tissue structure and houses resident cells. One ECM component, (beta)ig-h3, is a highly conserved transforming growth factor-beta-inducible protein that has been hypothesized to function as a bifunctional linker between individual matrix components and resident cells.