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Bladder Tissue (bladder + tissue)
Selected AbstractsDevelopment of a Model Bladder Extracellular Matrix Combining Disulfide Cross-Linked Hyaluronan with Decellularized Bladder TissueMACROMOLECULAR BIOSCIENCE, Issue 8 2006Allison L. Brown Abstract Summary: In this work we investigate the feasibility of modifying porcine-derived BAM to include HA with a view to developing a model, artificial extracellular matrix for the study of bladder cell-matrix interactions. HA-DPTH was incorporated into BAM disks and then cross-linked oxidatively to a disulfide containing hydrogel. Disks were seeded with bladder smooth muscle cells (BSMC) and UEC under three culture configurations and incubated for 3, 7, and 14 d. At each time point, matrix contraction was measured, and media supernatants assayed for cell-secreted gelatinase activity. To evaluate cell adherence and organization, triple immunofluorescent labeling of cell nuclei, actin cytoskeleton, and focal contacts was performed. HA-modified BAM exhibited a significant increase in matrix contraction and induced a higher level of cell-secreted gelatinase activity compared to unmodified BAM. Immunofluorescent labeling demonstrated that BSMCs remained adherent to both scaffold types over time. The distribution and organization of the cytoskeleton and focal contacts did not appear to be altered by the presence of HA. Interestingly, cellular infiltration into modified BAM was evident by 7 d and continued beyond 14 d, while BSMCs seeded onto unmodified BAM remained localized to the surface out to 14 d, with minimal infiltration evident only at day 28. These differences in cell infiltration support the gelatinase activity results. Increases in cell migration and matrix proteolysis in the presence of HA may be contributing factors toward BAM remodeling leading to increased matrix contraction with time. The model ECM developed in this work will be utilized for future studies aimed at elucidating the mechanisms controlling key remodeling events associated with bladder repair. Matrix contraction of cell-seeded BAM scaffolds. [source] Alteration of urothelial-mediated tone in the ischemic bladder: Role of eicosanoids,NEUROUROLOGY AND URODYNAMICS, Issue 3 2004Kazem M. Azadzoi Abstract Aims Previously we showed that ischemia alters bladder smooth muscle contractility in the rabbit. This study investigates the role of urothelium and eicosanoid-release in ischemic bladder smooth muscle instability. Materials and Methods Male New Zealand white rabbits were divided into treated (n,=,12) and age-matched control (n,=,10) groups. The treated group underwent balloon endothelial injury of the iliac arteries, and then received 4 weeks of cholesterol diet, followed by 4 weeks of regular diet. The control group received a regular diet for 8 weeks. After 8 weeks, blood flow for both the iliac arteries and the bladder as well as bladder oxygen tension were recorded. In one-half of each ischemic and control bladder, the urothelium was removed. Bladder tissues were processed for organ bath and enzyme-immunoassay (EIA) of prostaglandins (PGs) and leukotrienes (LTs). Results A significant decrease in iliac arterial blood flow, bladder wall blood flow, and bladder oxygen tension was found in the treated group. Bladder ischemia increased the frequency and amplitude of baseline spontaneous smooth muscle contractility. Ischemic tissues with urothelium (Uro+) demonstrated significant increases in the contractile response to electrical field stimulation (EFS) and carbachol relative to control Uro+ tissues. Urothelial removal increased smooth muscle contraction in the control tissues but had no significant effect in the ischemic/hypoxic tissues. Contraction of control tissues without urothelium (Uro,) was similar to contraction of ischemic Uro+ tissues. Contractions of ischemic Uro+ and control Uro, tissues were unchanged after treatment with the cyclooxygenase (COX) inhibitor indomethacin, while they were significantly reduced by the 5-lipoxygenase (5-LO) inhibitor NDGA. EIA showed no change in PGs release from the ischemic urothelium, but significant increase in PGF2-, and thromboxane A2 release from the ischemic suburothelial tissue. Ischemia increased the release of LTB4, LTC4, and LTE4 from both urothelium and suburothelial tissue. Conclusions Our studies suggest loss of urothelial-mediated tone and LTs-mediated smooth muscle instability in the chronically ischemic/hypoxic bladder. Neurourol. Urodynam. 23:258,264, 2004. Published 2004 Wiley-Liss, Inc. [source] Effect of urothelium on bladder contractility in diabetic ratsINTERNATIONAL JOURNAL OF UROLOGY, Issue 7 2005MURAT KO Abstract Aim: It is known that physiopathological changes in diabetes affect the function of the bladder. In this study, we aimed to demonstrate the possible effects of diabetes on the urothelium during this physiopathological process. Methods: Diabetes was induced in rats by tail vein injection of 35 mg/kg streptozotocin. Eight weeks later, intact and denuded bladder strips were prepared from these rats. Electrical field stimulation (EFS; 0.5,32 Hz), carbachol (10,8,10,3 mol/L; cumulative dosage-response curves) and KCl (120 mmol/L) were used for the evaluation of the contractile responses. All responses were expressed as mg tension developed per mg of bladder tissue. Weights of rats and of their bladders, blood glucose levels, and frequency- and concentration,response curves were compared using anova, the paired t -test and the independent t -test. Differences were considered significant at P < 0.05. Results: Although no differences related to the weight of bladders of the control and diabetic groups were observed, there were differences in blood glucose levels and body weights between the two groups. Similarly, although there were no differences between the data obtained with EFS and KCl from tissues with intact and denuded strips in the control group, carbachol responses significantly differed between intact and denuded strips in the non-diabetic group. These differences were not observed in the diabetic group. In the control groups, in the presence of additional strips with intact urothelium placed in the medium containing denuded tissue, the differences in contractile responses between the intact control strip and the denuded strip disappeared. Conclusions: Diabetes possibly changes the interaction between the relaxant factors that are released from urothelium and muscarinic stimulation, but these interactions are not completely understood yet. Consequently, the response of the bladder to contractile stimulants is also affected. Further studies are required to reveal the mechanism by which diabetes influences the urothelium. [source] Functional Role of ,3-Adrenoreceptors in the BladderLUTS, Issue 2009Masahide HIGAKI The detrusor muscle contains ,-adrenoceptors (,-AR) and three subtypes, such as ,1-AR, ,2-AR, and ,3-AR, which have been identified in most species. There is a predominant expression of ,3-AR messenger RNA in human bladder tissue when compared with the ,1-AR and ,2-AR subtypes. Moreover, the presence of ,1, ,2, and ,3-AR in the human urothelium has been identified. It has also been demonstrated in animals that relaxation mediated through ,s-AR is achieved solely by cAMP-dependent mechanisms in non-contracted detrusor muscles, whereas in KCl precontracted detrusor muscles, cAMP-dependent and -independent mechanisms by way of calcium-activated K +(BK Ca) channels may be involved in ,-adrenergic relaxation. In addition, a recent phase II proof-of-concept study using a novel selective ,3-adrenoceptor agonist (YM178) has shown clinical efficacy in the treatment of overactive bladder (OAB) symptoms, suggesting that ,3-AR should be used as a therapeutic target for the treatment of OAB disorders. [source] Biomechanics of Diabetic BladdersLUTS, Issue 2009Chung Cheng WANG Objectives: Biomechanics is the mechanics applied to biology and we hereby review bladder biomechanics in diabetic bladder dysfunction. Methods: The important mechanical properties of bladder tissue include the stress-strain relationship, viscoelasticity and active contraction. Using biaxial mechanical testing methods, the diabetic bladders exhibited non-linear stress-strain mechanical relationships with increasing stiffness at higher stretches in both circumferential and longitudinal directions. Results: The diabetic bladders showed mechanical anisotropy with a greater compliance in the circumferential direction than in the longitudinal direction. The time-course study suggested that diuresis mainly contributed to the "early" changes of the mechanical properties with "late" changes induced by other diabetic effects. Conclusion: The biomechanical study of the urinary bladder has offered a novel understanding of the pathophysiology of diabetic cystopathy and we believe the collaboration of urology and engineering will contribute greatly to the treatment of diabetic bladder dysfunction in the future. [source] Evaluating the In Vitro and In Vivo Efficacy of Nano-Structured Polymers for Bladder Tissue Replacement ApplicationsMACROMOLECULAR BIOSCIENCE, Issue 5 2007Megan Pattison Abstract Bladder cancers requiring radical cystectomy, along with congenital and acquired disorders which result in obstruction of the bladder, necessitate surgical measures (including augmentation); such diagnoses bring a clinical need for effective bladder replacement implant designs. Many recent approaches for the design of soft tissue replacement materials have relied on the use of synthetic polymeric substances; unfortunately, the optimal soft tissue implant material is yet to be found. This may, in part, be because current polymeric formulations fail to sufficiently biomimic the neighboring bladder tissue. This study took a brand new approach in designing the next generation of tissue-engineered bladder constructs through the use of nanotechnology, or materials with nanometer (less than 100 nm) surface features. Results provided evidence that nano-structured polymeric scaffolds (specifically, PLGA and PU) created using chemical etching techniques are capable of enhancing the human bladder smooth muscle cell adhesion, proliferation, and the production of extracellular matrix (ECM) proteins. Preliminary in vivo results also speak to the usefulness of such nano-structured materials. In combination, these findings suggest that nano-dimensional PLGA and PU scaffolds are promising replacement materials for the human bladder wall. [source] Smooth muscle caveolae differentially regulate specific agonist induced bladder contractions,NEUROUROLOGY AND URODYNAMICS, Issue 1 2007V. Cristofaro Abstract Aims Caveolae are cholesterol-rich plasmalemmal microdomains that serve as sites for sequestration of signaling proteins and thus may facilitate, organize, and integrate responses to extracellular stimuli. While previous studies in the bladder have demonstrated alterations in caveolae with particular physiologic or pathologic conditions, little attention has been focused on the functional significance of these organelles. Therefore, the purpose of this study was to investigate the role of caveolae in the modulation of receptor-mediated signal transduction and determine the presence and localization of caveolin proteins in bladder tissue. Methods Contractile responses to physiologic agonists were measured in rat bladder tissue before and after disruption of caveolae achieved by depleting membrane cholesterol with methyl-,-cyclodextrin. Stimulation with agonists was repeated after caveolae were restored as a result of cholesterol replenishment. RT-PCR, immmunohistochemistry, and Western blotting were used to determine the expression and localization of caveolin mRNA and proteins. Results Following caveolae disruption, contractile responses to angiotensin II and serotonin were attenuated, whereas responses to bradykinin and phenylephrine were augmented. Cholesterol replenishment restored responses towards baseline. Carbachol and KCl induced contractions were not affected by caveolae disruption. Ultrastructure analysis confirmed loss of caveolae following cholesterol depletion with cyclodextrin and caveolae restoration following cholesterol replacement. Gene and protein expression of caveolin-1, -2, and -3 was detected in bladder tissue. Immunoreactivity for all three caveolins was observed in smooth muscle cells throughout the bladder. Conclusions The functional effects of cholesterol depletion on specific agonist-induced contractile events and the expression of all three caveolins in bladder smooth muscle support a central role for caveolae in regulation of selective G-protein-coupled receptor signaling pathways in bladder smooth muscle. Thus, caveolae serve to differentially regulate bladder smooth muscle by a stimulus-dependent potentiation or inhibition of bladder contraction. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source] USE OF PORCINE SMALL INTESTINAL SUBMUCOSA IN BLADDER AUGMENTATION IN RABBIT: LONG-TERM HISTOLOGICAL OUTCOMEANZ JOURNAL OF SURGERY, Issue 1-2 2008Ali Ayyildiz Aim: To investigate long-term histological features of bladder augmentation using porcine small intestine submucosa (SIS) in a rabbit model. Materials and method: Sixteen New Zealand rabbits were used. Porcine SIS was provided by a manufactured formation derived from the pig. After partial cystectomy was carried out on the bladder, a single layer of SIS (Cook® -SIS Technology, Cook Biotech Incorporated, West Lafayette, IN, USA) (2 × 5 cm) was sewn to bladder with continuous 5/0 vicryl suture material in a watertight manner. Urinary diversion was not used. The rabbits were killed 12 months later and perivesical fat was removed together with bladder. The 5-,m preparations taken from the samples were stained with haematoxylin,eosin and Mason's trichrome dye. S-100 and F8 stains were also used for immunohistochemical investigations. Results: The macroscopic view of bladder was normal. SIS was indistinguishable from normal bladder wall, but the region of the graft had a slight white coloration. Microscopic observations showed the continuity of transitional epithelium of host bladder tissue on SIS material. Detrusor and serosal layers were formed and these layers were indistinguishable from host bladder. Fibroblasts were scattered among the collagen fibrils. New vessel formations were present without lymphatic proliferation. Nerve regeneration was excellent. No inflammation was observed in normal and regenerated bladder wall. Conclusion: At the end of 12 months, the long-term histological features of bladder augmentation with porcine SIS in a rabbit model, such as presence of new vessel formations, nerve regeneration, collagen and smooth muscle regenerations, which were indistinguishable from original bladder, and the absence of inflammation, showed that SIS seems to be a viable alternative to the use of intestine in bladder augmentation. [source] Herpes simplex virus type-2 in Egyptian patients with bladder cancer or cystitisAPMIS, Issue 1 2010HALA BADAWI Badawi H, Ahmed H, Aboul Fadl L, Helmi A, Fam N, Diab M, Ismail A, Badawi A, Saber M. Herpes simplex virus type-2 in Egyptian patients with bladder cancer or cystitis. APMIS 2010; 118: 37,44. The present study was designed to investigate the prevalence of herpes simplex virus type-2 (HSV-2) in Egyptian patients with bladder cancer or cystitis and to evaluate the performance of different diagnostic HSV-2 assays. The study included 50 patients: 27 with bladder cancer (group I), 23 with cystitis (group II) and 20 subjects as controls (group III). HSV-2 DNA was detected using polymerase chain reaction (PCR) on bladder tissue and buffy coat cells (BCC). Electron microscopic studies (EMS) on BCC and ELISAs for IgM, IgG and specific glycoprotein G-2 (gG-2) IgG were performed. HSV-2 DNA was detected by PCR on bladder tissue biopsies in 29.6% and 21.7% of group I and II respectively and it was also detected by PCR on BCC in 22.2% and 21.7% of group I and II respectively. EMS revealed HSV like particles in 16.6% of cases. IgG, specific gG-2 IgG and IgM were detected in 30%, 16% and 6% of cases respectively. The different assays were evaluated in relation to PCR on bladder tissue biopsies. The gG-2-based ELISA and EMS on BCC were found to be highly specific (97.3% and 100% respectively), with similar low sensitivity of ,54%. PCR on BCC was the most sensitive assay. The association of HSV-2 with bladder cancer is suggested especially in schistosomal patients. [source] Cyclooxygenase-2 expression on urothelial and inflammatory cells of cystoscopic biopsies and urine cytology as a possible predictive marker for bladder carcinomaAPMIS, Issue 1 2009MONA MOUSSA Cyclooxygenase-2 (COX-2) is a key inducible enzyme involved in the production of prostaglandins. It contributes to human carcinogenesis by various mechanisms. The aim of the current study was to elucidate the possible involvement of COX-2 in human bladder carcinoma by examining its expression on both urothelial and inflammatory cells in tissue biopsies and urine cytology samples of different urinary bladder lesions. A total of 65 patients were included in the study and were selected from cases admitted to Urology Department, Theodor Bilharz Research Institute (TBRI), Giza, Egypt. They represented seven control cases with almost normal-looking bladder tissue; pure chronic cystitis (n=12); premalignant lesions (18) in the form of squamous metaplasia (n=8) or urothelial dysplasia (n=10) as well as transitional cell carcinoma (TCC) (n=18), and squamous cell carcinoma (SqCC) (n=10). Immunohistochemistry of formalin-fixed, paraffin-embedded tissue sections and urine cytology samples was performed for all cases using COX-2 (H-62): sc-7951, a rabbit polyclonal antibody. The study revealed positive COX-2 expression on the urothelial and inflammatory cells of cystoscopic biopsies from all cases of pure chronic cystitis, squamous metaplasia and SqCC compared with 42.8% and 71.4% of normal controls, respectively. The score of urothelial COX-2 expression was sequentially up-regulated from normal to chronic cystitis (either pure or associated with premalignant changes) (p<0.05) to malignant changes (p<0.05). However, the inflammatory cellular expression was down-regulated with malignant transformation compared with chronic cystitis (p<0.05). In TCC, COX-2 was over-expressed on both urothelial and inflammatory cells in advanced tumors. Urine cytology samples were positive for COX-2 in a comparable manner to that observed in cystoscopic biopsies. Accordingly, the results of the current study have provided new information in two aspects: First, is the possibility of using the differential COX-2 expression on both inflammatory and urothelial cells as markers for premalignant or malignant transformation; second, besides cystoscopy, urine cytology was found to have a high sensitivity for COX-2 expression and hence proved to be valuable in malignancy as a non-invasive substitute for cystoscopy. [source] The Boari bladder flap: an effective continent stoma for the high-compliance neurogenic bladderBJU INTERNATIONAL, Issue 9 2010Egbert Baumgart Study Type , Therapy (case series) Level of Evidence 4 OBJECTIVE To determine if a continent urinary stoma can be created effectively using a Boari bladder flap (BBF) technique. PATIENTS AND METHODS Selected patients (15, eight women and seven men) with a neurogenic bladder and a bladder compliance of >20 mL/cmH2O had a procedure to create a BBF continent urinary stoma. The technique consisted of tubularising a trapezoidal, full-thickness detrusor flap 10 cm long, 5,6 cm wide at the base and 2 cm at the tip, over a 12 F catheter, and plication of detrusor muscle around the stomal base. Outcomes after surgery were assessed by reviewing stomal continence, stomal patency, and stability of the upper urinary tract. RESULTS Ten BBF procedures were performed using native detrusor muscle, four with enterocystoplasty tissue and one in a defunctionalized bladder. Over a mean follow-up of 13 months, 11 patients had functioning stomas and 10 of these reported complete stomal continence. The mean change in serum creatinine level from the preoperative baseline for all patients was 0.1 mg/dL. The odds ratio for procedural failure, defined as a stoma unusable for self-catheterization, was 7.5 (P = 0.04) when the BBF was created from augmented or defunctionalized bladder tissue, compared to native high-compliance detrusor. CONCLUSION A BBF can be used to create a viable, functional stoma in the high-compliance neurogenic bladder, although the rate of stomal complications is high when the BBF is created from enterocystoplasty tissue. [source] Using gene chips to identify organ-specific, smooth muscle responses to experimental diabetes: potential applications to urological diseasesBJU INTERNATIONAL, Issue 2 2007Jason D. Hipp OBJECTIVE To identify early diabetes-related alterations in gene expression in bladder and erectile tissue that would provide novel diagnostic and therapeutic treatment targets to prevent, delay or ameliorate the ensuing bladder and erectile dysfunction. MATERIALS AND METHODS The RG-U34A rat GeneChip® (Affymetrix Inc., Sunnyvale, CA, USA) oligonucleotide microarray (containing ,8799 genes) was used to evaluate gene expression in corporal and male bladder tissue excised from rats 1 week after confirmation of a diabetic state, but before demonstrable changes in organ function in vivo. A conservative analytical approach was used to detect alterations in gene expression, and gene ontology (GO) classifications were used to identify biological themes/pathways involved in the aetiology of the organ dysfunction. RESULTS In all, 320 and 313 genes were differentially expressed in bladder and corporal tissue, respectively. GO analysis in bladder tissue showed prominent increases in biological pathways involved in cell proliferation, metabolism, actin cytoskeleton and myosin, as well as decreases in cell motility, and regulation of muscle contraction. GO analysis in corpora showed increases in pathways related to ion channel transport and ion channel activity, while there were decreases in collagen I and actin genes. CONCLUSIONS The changes in gene expression in these initial experiments are consistent with the pathophysiological characteristics of the bladder and erectile dysfunction seen later in the diabetic disease process. Thus, the observed changes in gene expression might be harbingers or biomarkers of impending organ dysfunction, and could provide useful diagnostic and therapeutic targets for a variety of progressive urological diseases/conditions (i.e. lower urinary tract symptoms related to benign prostatic hyperplasia, erectile dysfunction, etc.). [source] The effect of serotonin and serotonin antagonists on bladder cancer cell proliferationBJU INTERNATIONAL, Issue 3 2006EMAD J. SIDDIQUI OBJECTIVE To investigate the role of serotonin (5-hydroxytryptamine, 5HT) and its antagonists in the proliferation of high-grade bladder cancer cells (HT1376), as high-grade bladder cancer has a rapid rate of progression, invasion and recurrence, and 5HT antagonists inhibit the growth of the prostate cancer cell line (PC3). MATERIALS AND METHODS HT1376 (human grade III transitional cell carcinoma) cells were incubated with either 5HT or 5HT antagonists (5HT1A, 5HT1B, 5HT1D, 5HT2, 5HT3 and 5HT4). After 72 h, cell viability was assessed using the crystal violet assay. The presence of 5HT receptor subtypes on HT1376 cells and sections of human bladder cancer tissue was determined by immunohistochemistry and Western blot analysis. RESULTS 5HT caused a dose-dependent increase in the proliferation of HT1376 cells. The maximum increase in cell proliferation (12%; 12 samples, P < 0.001) was at 10,8m as compared to the control at 72 h. At 10,4m, 5HT1A antagonist (NAN-190 hydrobromide) and 5HT1B antagonist (SB224289 hydrochloride) had a 10% (12 samples, P < 0.001) and 93% (12, P < 0.001) inhibitory effect on HT1376 cell growth, respectively, compared to the control at 72 h. There was immunostaining for 5HT1A and 5HT1B receptors in HT1376 cells and malignant bladder tissue, confirming the presence of these two receptor subtypes. Western blot analysis showed the presence of 5HT1A and 5HT1B receptor proteins with bands of 46 kDa and 43 kDa, respectively. CONCLUSION 5HT1A and to a greater extent 5HT1B antagonists significantly inhibit bladder cancer cell growth. This effect is probably mediated via the 5HT1A and 5HT1B receptors. These results highlight the potential use of 5HT1A and 5HT1B antagonists in the treatment of bladder cancer. [source] Mitochondrial metabolism in the rat during bladder regeneration induced by small intestinal submucosaBJU INTERNATIONAL, Issue 3 2004Rozbeh Faramarzi-Roques OBJECTIVE To assess mitochondrial metabolism of bladder tissue induced by small-intestinal submucosa (SIS), by comparing the mitochondrial enzyme metabolism in this tissue with that in normal bladder tissue and thus evaluate intracellular normality. MATERIAL AND METHODS In all, 70 rats were grouped into healthy controls (10), surgical controls with a simple bladder incision (15) and rats treated by partial cystectomy with replacement by the SIS graft (45). At 1, 3 and 6 months the rats were killed, the enzymes of mitochondrial respiratory chain complexes assayed, and the respiration of permeabilized bladder fibres assessed using polarographic analysis. RESULTS The enzyme activities of control and treated rats at 3 months were identical. The results from the polarographic analysis of respiration were also similar to that in normal tissue apart from a decrease in the number of mitochondria. Histologically, there was complete regeneration at 6 months. CONCLUSION After a phase of inflammation the bladder regenerates after a patch is placed. The new tissue has the same enzymatic and histological features as normal bladder tissue. [source] Bladder wall tension during physiological voiding and in patients with an unstable detrusor or bladder outlet obstructionBJU INTERNATIONAL, Issue 6 2003S. Bross OBJECTIVE To develop and evaluate a new clinical method for measuring bladder wall tension (BWT) on detrusor contraction during physiological voiding and under pathological conditions, as in experimental trials during subvesical obstruction the ability to generate pressure increases, whereas the contractile force per cross-sectional area of detrusor muscle decreases. PATIENTS AND METHODS In all, 24 patients were divided into three equal groups: group 1 (mean age 58, sd 8.6 years) comprised men with bladder outlet obstruction in accordance with the Abrams-Griffiths nomogram; group 2 (four men and four women, 56, sd 7.2 years) had detrusor instability; and group 3 (54, sd 9.6 years) had normal bladder emptying. BWT, as the detrusor force per cross-sectional area of bladder tissue (in N/cm2), was calculated after a urodynamic evaluation and ultrasonographic estimate of bladder wall thickness. RESULTS In all patients it was possible to measure BWT; the mean (sd) maximum BWT in group 1 was 9.8 (3.9) N/cm2, in group 2 during bladder instability was 11.7 (2.6) N/cm2 and in group 3 was 2.8 (0.5) N/cm2. CONCLUSIONS Estimating BWT in humans is possible by combining a urodynamic evaluation with an ultrasonographic estimate of bladder wall thickness. Further clinical research should elucidate the clinical relevance of BWT under comparable conditions. [source] Gastrointestinal, selective airways and urinary bladder relaxant effects of Hyoscyamus niger are mediated through dual blockade of muscarinic receptors and Ca2+ channelsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 1 2008Anwarul Hassan Gilani Abstract This study describes the spasmolytic, antidiarrhoeal, antisecretory, bronchodilatory and urinary bladder relaxant properties of Hyoscyamus niger to rationalize some of its medicinal uses. The crude extract of H. niger seeds (Hn.Cr) caused a complete concentration-dependent relaxation of spontaneous contractions of rabbit jejunum, similar to that caused by verapamil, whereas atropine produced partial inhibition. Hn.Cr inhibited contractions induced by carbachol (1 ,m) and K+ (80 mm) in a pattern similar to that of dicyclomine, but different from verapamil and atropine. Hn.Cr shifted the Ca2+ concentration,response curves to the right, similar to that caused by verapamil and dicyclomine, suggesting a Ca2+ channel-blocking mechanism in addition to an anticholinergic effect. In the guinea-pig ileum, Hn.Cr produced a rightward parallel shift of the acetylcholine curves, followed by a non-parallel shift with suppression of the maximum response at a higher concentration, similar to that caused by dicyclomine, but different from that of verapamil and atropine. Hn.Cr exhibited antidiarrhoeal and antisecretory effects against castor oil-induced diarrhoea and intestinal fluid accumulation in mice. In guinea-pig trachea and rabbit urinary bladder tissues, Hn.Cr caused relaxation of carbachol (1 ,m) and K+ (80 mm) induced contractions at around 10 and 25 times lower concentrations than in gut, respectively, and shifted carbachol curves to the right. Only the organic fractions of the extract had a Ca2+ antagonist effect, whereas both organic and aqueous fractions had anticholinergic effect. A constituent, ,-sitosterol exhibited Ca2+ channel-blocking action. These results suggest that the antispasmodic effect of H. niger is mediated through a combination of anticholinergic and Ca2+ antagonist mechanisms. The relaxant effects of Hn.Cr occur at much lower concentrations in the trachea and bladder. This study offers explanations for the medicinal use of H. niger in treating gastrointestinal and respiratory disorders and bladder hyperactivity. [source] Changes in expression and activity of glutathione S -transferase in different organs of schistosoma haematobium -infected hamsterJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 3 2003S. A. Sheweita Abstract Schistosomiasis is a major health problem in many subtropical developing countries, causing a number of serious pathologies, including bladder cancer. Most of the toxic compounds formed as a result of these infestations are derived either exogenously or formed endogenously and can be conjugated with glutathione (GSH) via glutathione S-transferase (GST). The present study investigates the effect of Schistosma haematobium infection on the activity of GST and glutathione reductase (GR) and levels of glutathione and free radicals (measured as thiobarbituric acid reactive substances) in different organs of the male hamster. The total activity of GST was increased in several organs; in kidney by 50 and 46% at 6 and 10 weeks postinfection, respectively, and in bladder tissues by 169, 23, and 130% at 2, 4, and 6 weeks postinfection, respectively. In support of this, the expression of GST isozymes was also induced in kidney and bladder tissues at early stages (2, 4, and 6 weeks) and reduced at the later stages of infection (8 and 10 weeks). In contrast, the expression of these isozymes was decreased in the spleen and liver at 2, 4, 6, 8, and 10 weeks postinfection. Also, such activity was decreased in lungs by 74 and 78% and in bladders by 65 and 72% at 8 and 10 weeks postinfection, respectively. GSH levels increased in lungs by 95, 40, and 56% at 2, 4, and 6 weeks and in spleen by 26 and 74% at 4 and 6 weeks, respectively, but decreased at later stages of S. haematobium infection in these organs. The depletion of GSH levels also occurred in bladders by 72 and 54% at 8 and 10 weeks postinfection, respectively. The activity of GR was increased in the livers, lungs, and kidneys of the S. haematobium -infected hamster. TBARS also increased in the lung by 14, 65, 53, 828, and 624% and in the kidney by 64, 29, 87, 190, and 111%, and in the bladder by 216, 23, 1468, 528, and 1025% at 2, 4, 6, 8, and 10 weeks postinfection, respectively. This study indicates that low GST expression and high levels of free radicals could provide new evidence for damage to the bladder and other organs as a result of S. haematobium infection. © 2003 Wiley Periodicals, Inc. J Biochem Mol Toxicol 17:138,145, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.10071 [source] Characterization of apoptosis induced by grouper iridovirus in two newly established cell lines from barramundi, Lates calcarifer (Bloch)JOURNAL OF FISH DISEASES, Issue 11 2008Y-S Lai Abstract Two new cell lines have been established from the muscle and swim bladder tissues of barramundi, Lates calcarifer, and designated as BM (barramundi muscle) and BSB (barramundi swimbladder), respectively. The cells multiplied well at 28 °C in Leibovitz's L-15 medium supplemented with 10% foetal bovine serum, and have been continuously subcultured more than 100 times to date. Morphologically, BM cells were mostly fibroblastic, whereas BSB were mostly epithelial. Both cell lines were susceptible to grouper iridovirus (GIV) and displayed characteristics of apoptosis after viral infection. The induction of apoptosis was further assayed in GIV-infected BM and BSB cells by various methods. The inhibition of cell growth by GIV was demonstrated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Morphological observations revealed typical apoptotic features in the infected cells, including cell shrinkage and rounding, chromosome condensation and formation of apoptotic body-like vesicles. Chromosome fragmentation was detected by DNA laddering and TUNEL assays. Finally, the appearance of phosphotidylserine on the outer leaflet of apoptotic cell membranes was confirmed by annexin V staining. This is the first report of apoptosis induced by GIV in fish cells. [source] Melatonin attenuates ifosfamide-induced Fanconi syndrome in ratsJOURNAL OF PINEAL RESEARCH, Issue 1 2004Goksel Sener Abstract:, Regarding the mechanisms of ifosfamide (IFO)-induced nephrotoxicity and hemorrhagic cystitis, several hypotheses have been put forward, among which oxidative stress and depletion of glutathione (GSH) are suggested. This investigation elucidates the role of free radicals in IFO-induced toxicity and the protection by melatonin. Wistar albino rats were injected intraperitoneally with saline (0.9% NaCl; control-C group), melatonin (Mel group; 10 mg/kg daily for 5 days) or ifosfamide (50 mg/kg daily for 5 days; IFO group) or IFO + Mel. On the 5th day (120 hr) after the first IFO dose, animals were killed by decapitation and trunk blood was collected. Kidney and bladder tissues were obtained for biochemical and histological analysis. Urine was collected 24 hr before the rats were killed. The results demonstrated that IFO induced a Fanconi syndrome (FS) characterized by wasting of sodium, phosphate, and glucose, along with increased serum creatinine and urea. Melatonin markedly ameliorated the severity of renal dysfunction induced by IFO with a significant decrease in urinary sodium, phosphate, and glucose and increased creatinine excretion. Moreover, melatonin significantly improved the IFO-induced GSH depletion, malondialdehayde accumulation and neutrophil infiltration in both renal and bladder tissues. In the kidney, Na+,K+ -ATPase activity which was significantly reduced by IFO, was increased with melatonin treatment. Increased collagen contents of the kidney and bladder tissues by IFO treatment were reversed back to the control levels with melatonin. Our results suggest that IFO causes oxidative damage in renal and bladder tissues and melatonin, via its antioxidant effects, protects these tissues. These data suggest that melatonin may be of therapeutic use in preventing acquired FS due to IFO toxicity. [source] Paclitaxel and cisplatin as intravesical agents against non-muscle-invasive bladder cancerBJU INTERNATIONAL, Issue 11 2008Boris A. Hadaschik OBJECTIVES To investigate the effects of cisplatin and paclitaxel against human bladder cancer cells in vitro, and to obtain both pharmacokinetic and pharmacodynamic data after intravesical administration in mice. MATERIALS AND METHODS Six bladder cancer cell lines (J82, KU7, RT4, SW780, T24, UMUC3) were treated with various combined doses of both drugs and cell proliferation was evaluated 3 days later. In vivo, solutions of cisplatin and micellar paclitaxel were instilled transurethrally in female mice and pharmacokinetic data were acquired using high-performance liquid chromatography-mass spectrometry and atomic absorption methods. To obtain efficacy data, mice with orthotopic KU7-luc tumours were administered cisplatin and/or micellar paclitaxel intravesically, and the tumour burden quantified using bioluminescence imaging. RESULTS In vitro, both cisplatin and paclitaxel potently decreased the proliferation of all cell lines tested, and in combination had an additive but not a synergistic effect. After intravesical instillation, mouse serum concentrations of cisplatin and paclitaxel were in the low microgram/millilitre range and bladder tissue concentrations achieved were 82 and 241 µg/g, respectively. Similar drug levels were reached using combined therapy. In vivo, all chemotherapeutic agents significantly inhibited bladder tumour growth, with the best results for combined therapy and micellar paclitaxel alone. However, there was toxicity in the combined treatment arm. CONCLUSIONS Both cisplatin and paclitaxel were absorbed at effective amounts into bladder tissues. As intravesical agents, paclitaxel had slightly stronger anticancer potency than cisplatin. Due to increased adverse events, caution should be exercised when combining both cisplatin and paclitaxel intravesically. [source] Effects of ovariectomy and oestrogen replacement on the function and expression of Rho-kinase in rat bladder smooth muscleBJU INTERNATIONAL, Issue 5 2006Sung K. Hong OBJECTIVE To investigate the effects of ovariectomy and oestrogen replacement on the function and expression of Rho-kinase in rat bladder smooth muscle, as the actual effects of oestrogen deprivation on bladder smooth muscle are unclear. MATERIALS AND METHODS Female Sprague,Dawley rats were placed into one of three groups: sham-operated, bilateral ovariectomy-only, and bilateral ovariectomy plus oestrogen replacement groups. In the last group, oestrogen was replaced by weekly injection of ,-estradiol 17-cypionate (250 µg/kg subcutaneously for 6 weeks) beginning at 1 week after ovariectomy, whereas the other groups received vehicle-only injections for 6 weeks. After treatment, the bladder was removed for muscle strip studies to evaluate the effects of Y-27632, a specific inhibitor of Rho-kinase, on baseline tension and carbachol-induced tonic contractions. Also, the protein expression of RhoA and Rho-kinase isoenzymes was assessed by Western blot analysis. RESULTS Of the three groups, incubation with 10 µm Y-27632 resulted in the largest decrease in baseline tension of strips from the bilateral ovariectomy-only group, but this was not statistically significant (P > 0.05). For carbachol-induced tonic contractions, strips from the bilateral ovariectomy-only group were attenuated the most among the three groups after adding Y-27632 (P < 0.05). However, there were no significant differences in the levels of RhoA and the two Rho-kinase isoenzymes in bladder tissues from the three groups. CONCLUSION Our data show that oestrogen might inhibit the function of Rho-kinase in bladder smooth muscle, while having no significant effect on its expression. This finding might help to explain the greater incidence of urinary tract symptoms suggestive of overactive bladder after the menopause in women. [source] | |||||||||||||