scholarly journals An ex vivo bladder model with detrusor smooth muscle removed to analyse biologically active mediators released from the suburothelium

2018 ◽  
Vol 597 (6) ◽  
pp. 1467-1485 ◽  
Author(s):  
Leonie Durnin ◽  
Benjamin Kwok ◽  
Priya Kukadia ◽  
Roisin McAvera ◽  
Robert D. Corrigan ◽  
...  
2015 ◽  
Vol 9 (9-10) ◽  
pp. 599 ◽  
Author(s):  
Hazem Orabi ◽  
Alexandre Rousseau ◽  
Véronique Laterreur ◽  
Stéphane Bolduc

Introduction: Due to the complications associated with the use of non-native biomaterials and the lack of local tissues, bioengineered tissues are required for surgical reconstruction of complex urinary tract diseases, including those of the urinary bladder. The selfassembly method of matrix formation using autologous stromal cells obviates the need for exogenous biomaterials. We aimed at creating novel ex-vivo multilayer urinary tissue from a single bladder biopsy.Methods: After isolating urothelial, bladder stromal and smooth muscle cells from bladder biopsies, we produced 2 models of urinary equivalents: (1) the original one with dermal fibroblasts and (2) the new one with bladder stromal cells. Dermal fibroblasts and bladder stromal cells were stimulated to form an extracellular matrix, followed by sequential seeding of smooth muscle cells and urothelial cells. Stratification and cellular differentiation were assessed by histology, immunostaining and electron microscopy. Barrier function was checked with the permeability test. Biomechanical properties were assessed with uniaxinal tensile strength, elastic modulus, and failure strain.Results: Both urinary equivalents could be handled easily and did not contract. Stratified epithelium, intact basement membrane, fused matrix, and prominent muscle layer were detected in both urinary equivalents. Bladder stromal cell-based constructs had terminally differentiated urothelium and more elasticity than dermal fibroblasts-based equivalents. Permeation studies showed that both equivalents were comparable to native tissues.Conclusions: Organ-specific stromal cells produced urinary tissues with more terminally differentiated urothelium and better biomechanical characteristics than non-specific stromal cells. Smooth muscle cells could be incorporated into the selfassembled tissues effectively. This multi-layer tissue can be used as a urethral graft or as a bladder model for disease modelling and pharmacotherapeutic testing.


2007 ◽  
Vol 177 (4S) ◽  
pp. 86-86
Author(s):  
Stephanie Oger ◽  
Delphine Behr-Roussel ◽  
Katell Mevel ◽  
Jacques Bernabe ◽  
Pierre Denys ◽  
...  

2007 ◽  
Vol 177 (4S) ◽  
pp. 124-124
Author(s):  
Navroop S. Johal ◽  
Peter M. Cuckow ◽  
Christopher H. Fry

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Antara Chatterjee ◽  
Rojan Saghian ◽  
Anna Dorogin ◽  
Lindsay S. Cahill ◽  
John G. Sled ◽  
...  

AbstractThe cervix is responsible for maintaining pregnancy, and its timely remodeling is essential for the proper delivery of a baby. Cervical insufficiency, or “weakness”, may lead to preterm birth, which causes infant morbidities and mortalities worldwide. We used a mouse model of pregnancy and term labor, to examine the cervical structure by histology (Masson Trichome and Picrosirius Red staining), immunohistochemistry (Hyaluronic Acid Binding Protein/HABP), and ex-vivo MRI (T2-weighted and diffusion tensor imaging), focusing on two regions of the cervix (i.e., endocervix and ectocervix). Our results show that mouse endocervix has a higher proportion of smooth muscle cells and collagen fibers per area, with more compact tissue structure, than the ectocervix. With advanced gestation, endocervical changes, indicative of impending delivery, are manifested in fewer smooth muscle cells, expansion of the extracellular space, and lower presence of collagen fibers. MRI detected three distinctive zones in pregnant mouse endocervix: (1) inner collagenous layer, (2) middle circular muscular layer, and (3) outer longitudinal muscular layer. Diffusion MRI images detected changes in tissue organization as gestation progressed suggesting the potential application of this technique to non-invasively monitor cervical changes that precede the onset of labor in women at risk for preterm delivery.


Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 147
Author(s):  
Romuald Brice Babou Kammoe ◽  
Gilles Kauffenstein ◽  
Julie Pelletier ◽  
Bernard Robaye ◽  
Jean Sévigny

Nucleotides released by smooth muscle cells (SMCs) and by innervating nerve terminals activate specific P2 receptors and modulate bladder contraction. We hypothesized that cell surface enzymes regulate SMC contraction in mice bladder by controlling the concentration of nucleotides. We showed by immunohistochemistry, enzymatic histochemistry, and biochemical activities that nucleoside triphosphate diphosphohydrolase-1 (NTPDase1) and ecto-5′-nucleotidase were the major ectonucleotidases expressed by SMCs in the bladder. RT-qPCR revealed that, among the nucleotide receptors, there was higher expression of P2X1, P2Y1, and P2Y6 receptors. Ex vivo, nucleotides induced a more potent contraction of bladder strips isolated from NTPDase1 deficient (Entpd1−/−) mice compared to wild type controls. The strongest responses were obtained with uridine 5′-triphosphate (UTP) and uridine 5′-diphosphate (UDP), suggesting the involvement of P2Y6 receptors, which was confirmed with P2ry6−/− bladder strips. Interestingly, this response was reduced in female bladders. Our results also suggest the participation of P2X1, P2Y2 and/or P2Y4, and P2Y12 in these contractions. A reduced response to the thromboxane analogue U46619 was also observed in wild type, Entpd1−/−, and P2ry6−/− female bladders showing another difference due to sex. In summary, NTPDase1 modulates the activation of nucleotide receptors in mouse bladder SMCs, and contractions induced by P2Y6 receptor activation were weaker in female bladders.


2021 ◽  
Vol 82 (5) ◽  
Author(s):  
Hannah J. Pybus ◽  
Amanda L. Tatler ◽  
Lowell T. Edgar ◽  
Reuben D. O’Dea ◽  
Bindi S. Brook

AbstractPrecision-cut lung-slices (PCLS), in which viable airways embedded within lung parenchyma are stretched or induced to contract, are a widely used ex vivo assay to investigate bronchoconstriction and, more recently, mechanical activation of pro-remodelling cytokines in asthmatic airways. We develop a nonlinear fibre-reinforced biomechanical model accounting for smooth muscle contraction and extracellular matrix strain-stiffening. Through numerical simulation, we describe the stresses and contractile responses of an airway within a PCLS of finite thickness, exposing the importance of smooth muscle contraction on the local stress state within the airway. We then consider two simplifying limits of the model (a membrane representation and an asymptotic reduction in the thin-PCLS-limit), that permit analytical progress. Comparison against numerical solution of the full problem shows that the asymptotic reduction successfully captures the key elements of the full model behaviour. The more tractable reduced model that we develop is suitable to be employed in investigations to elucidate the time-dependent feedback mechanisms linking airway mechanics and cytokine activation in asthma.


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