Null mutation in macrophage migration inhibitory factor prevents muscle cell loss and fibrosis in partial bladder outlet obstruction

Male Lower Urinary Tract Dysfunction: An Underrepresented Endpoint in Toxicology Research

Lower urinary tract dysfunction (LUTD) is nearly ubiquitous in men of advancing age and exerts substantial physical, mental, social, and financial costs to society. While a large body of research is focused on the molecular, genetic, and epigenetic underpinnings of the disease, little research has been dedicated to the influence of environmental chemicals on disease initiation, progression, or severity. Despite a few recent studies indicating a potential developmental origin of male LUTD linked to chemical exposures in the womb, it remains a grossly understudied endpoint in toxicology research. Therefore, we direct this review to toxicologists who are considering male LUTD as a new aspect of chemical toxicity studies. We focus on the LUTD disease process in men, as well as in the male mouse as a leading research model. To introduce the disease process, we describe the physiology of the male lower urinary tract and the cellular composition of lower urinary tract tissues. We discuss known and suspected mechanisms of male LUTD and examples of environmental chemicals acting through these mechanisms to contribute to LUTD. We also describe mouse models of LUTD and endpoints to diagnose, characterize, and quantify LUTD in men and mice.

MicroRNA-219c-5p regulates bladder fibrosis by targeting FN1

BACKGROUND

We found that the bladders of multiple sclerosis mice were significantly fibrotic. This study aimed to investigate the relationship between fibronectin 1 (FN1) and bladder fibrosis, as well as the microRNAs involved in FN1 regulation.

METHODS

The degree of bladder smooth muscle fibrosis was observed by immunohistochemistry. In addition, we used quantitative real-time polymerase chain reaction (RT-qPCR) and Western blotting to determine FN1 expression in bladders with different grades of fibrosis. Bioinformatics analysis revealed that miR-199a-3p, miR-219c-5p and miR-3572-3p could inhibit FN1 synthesis. Therefore, miR-199a-3p, miR-219c-5p and miR-3572-3p were overexpressed or knocked down in bladder smooth muscle cells (BSMCs), and the respective transfection and FN1 knockdown efficiencies were detected by RT-qPCR. Only miR-219c-5p overexpression and knockdown produced the expected results. A dual luciferase reporter assay was used to determine the targeting relationship between miR-219c-5p and FN1. Flow cytometry and Cell Counting Kit 8 (CCK8) experiments confirmed that miR-219c-5p reduced FN1 expression and affected the biological activity of smooth muscle cells. Agomir and anagomir of miR-219c-5p were transfected in vivo to observe the change of bladder fibrosis in mice.

RESULTS

With increasing bladder fibrosis, FN1 expression increased, while miR-199a-3p, miR-219c-5p, and miR-3572-3p expression levels decreased. The RT-qPCR results after transfection showed that only miR-219c-5p could regulate FN1. Indeed, the dual luciferase reporter assay results indicated that miR-219c-5p targeted FN1 directly. CCK8 and cell cycle assays showed that miR-219c-5p overexpression inhibited BSMC proliferation, while miR-219c-5p knockdown promoted BSMC proliferation. An apoptosis assay showed that miR-219c-5p overexpression promoted apoptosis, while miR-219c-5p knockdown inhibited BSMC apoptosis. The agomir and anagomir transfected with miR-219c-5p in vivo found that the bladder fibrosis of the mice in the agomir group was reduced, and the anagomir group was worse.

CONCLUSIONS

Our findings indicate that FN1 up-regulation and miR-219c-5p down-regulation play an important role in the development of bladder fibrosis, and miR-219c-5p participates in bladder fibrosis by regulating FN1 expression. Thus, a novel antifibrotic function of miR-219c-5p is proposed, which may represent a potential target for the diagnosis and treatment of bladder fibrosis.

Macrophage migration inhibitory factor contributes to the pathogenesis of benign lymphoepithelial lesion of the lacrimal gland

Background

Benign Lymphoepithelial Lesion (BLEL) is a rare disease observed in the adult population. Despite the growing numbers of people suffering from BLEL, the etiology and mechanisms underlying its pathogenesis remain unknown.

Methods

In the present study, we used gene and cytokines expression profiling, western blot and immunohistochemistry to get further insight into the cellular and molecular mechanisms involved in the pathogenesis of BLEL of the lacrimal gland.

Results

The results showed that Macrophage Migration Inhibitory Factor (MIF) was the most highly expressed cytokine in BLEL, and its expression positively correlated with the expression of Th2 and Th17 cells cytokines. MIF was found to regulate biological functions and pathways involved in BLEL pathogenesis, such as proliferation, resistance to apoptosis, MAPK and PI3K/Akt pathways. We also found that MIF promotes fibrosis in BLEL by inducing BLEL fibroblast differentiation into myofibroblasts as well as the synthesis and the deposit of extracellular matrix in BLEL tissues.

Conclusions

Our findings demonstrate the contribution of MIF to the pathogenesis of BLEL of the lacrimal gland and suggested MIF as a promising therapeutic target for its treatment.

Electronic supplementary material

The online version of this article (10.1186/s12964-018-0284-4) contains supplementary material, which is available to authorized users.

Age-related changes in function and gene expression of the male and female mouse bladder

We investigated age-related changes in in vivo and in vitro functions and gene expression of the bladder of male and female mice. Mature and aged (12 and 27–30 month old) C57BL/6 mice of both sexes were used. Frequency volume, conscious free-moving cystometry and detrusor contractile and relaxant properties in in vitro organ bath were evaluated. mRNA expression level of muscarinic, purinergic, and β-adrenergic receptors and gene expression changes by cDNA microarray analysis of the bladder were determined. Cystometry demonstrated storage and voiding dysfunctions with ageing in both sexes. Detrusor strips from aged mice showed weaker contractile responses particularly in the cholinergic component and weaker relaxant responses to isoproterenol. These age-related impairments were generally severer in males. mRNA expression of bladder tissue was decreased for M3 muscarinic receptors in aged males and β2-adrenoceptors in aged females. cDNA microarray analysis results, albeit substantial sex difference, indicated “cell-to-cell signaling and interaction” as the most common feature of age-related gene expression. In summary, aged mice demonstrated voiding and storage dysfunctions resembling to detrusor hyperactivity with impaired contractility (DHIC), which were more pronounced in males. Genomic changes associated with aging may contribute to the age-related bladder functional deterioration in mice.

Benefits and limitations of animal models in partial bladder outlet obstruction for translational research

The functions of the lower urinary tract have been investigated for more than a century. Lower urinary tract symptoms, such as incomplete bladder emptying, weak urine stream, daytime urinary frequency, urgency, urge incontinence and nocturia after partial bladder outlet obstruction, is a frequent cause of benign prostatic hyperplasia in aging men. However, the pathophysiological mechanisms have not been fully elucidated. The use of animal models is absolutely imperative for understanding the pathophysiological processes involved in bladder dysfunction. Surgical induction has been used to study lower urinary tract functions of numerous animal species, such as pig, dog, rabbit, guinea pig, rat and mouse, of both sexes. Several morphological and functional modifications under partial bladder outlet obstruction have not only been observed in the bladder, but also in the central nervous system. Understanding the changes of the lower urinary tract functions induced by partial bladder outlet obstruction would also contribute to appropriate drug development for treating these pathophysiological conditions. In the present review, we discuss techniques for creating partial bladder outlet obstruction, the characteristics of several species, as well as issues of each model, and their translational value.

Long-lasting effect of obesity on skeletal muscle transcriptome

BACKGROUND

Reduced physical activity and increased intake of calorically-dense diets are the main risk factors for obesity, glucose intolerance, and type 2 diabetes. Chronic overnutrition and hyperglycemia can alter gene expression, contributing to long-term obesity complications. While caloric restriction can reduce obesity and glucose intolerance, it is currently unknown whether it can effectively reprogram transcriptome to a pre-obesity level. The present study addressed this question by the preliminary examination of the transcriptional dynamics in skeletal muscle after exposure to overnutrition and following caloric restriction.

RESULTS

Six male rhesus macaques of 12-13 years of age consumed a high-fat western-style diet for 6 months and then were calorically restricted for 4 months without exercise. Skeletal muscle biopsies were subjected to longitudinal gene expression analysis using next-generation whole-genome RNA sequencing. In spite of significant weight loss and normalized insulin sensitivity, the majority of WSD-induced (n = 457) and WSD-suppressed (n = 47) genes remained significantly dysregulated after caloric restriction (FDR ≤0.05). The Metacore^TM pathway analysis reveals that western-style diet induced the sustained activation of the transforming growth factor-β gene network, associated with extracellular matrix remodeling, and the downregulation of genes involved in muscle structure development and nutritional processes.

CONCLUSIONS

Western-style diet, in the absence of exercise, induced skeletal muscle transcriptional programing, which persisted even after insulin resistance and glucose intolerance were completely reversed with caloric restriction.

Deletion of neuropilin 2 enhances detrusor contractility following bladder outlet obstruction

Chronic urethral obstruction and the ensuing bladder wall remodeling can lead to diminished bladder smooth muscle (BSM) contractility and debilitating lower urinary tract symptoms. No effective pharmacotherapy exists to restore BSM contractile function. Neuropilin 2 (Nrp2) is a transmembrane protein that is highly expressed in BSM. Nrp2 deletion in mice leads to increased BSM contraction. We determined whether genetic ablation of Nrp2 could restore BSM contractility following obstruction. Partial bladder outlet obstruction (pBOO) was created by urethral occlusion in mice with either constitutive and ubiquitous, or inducible smooth muscle-specific deletion of Nrp2, and Nrp2-intact littermates. Mice without obstruction served as additional controls. Contractility was measured by isometric tension testing. Nrp2 deletion prior to pBOO increased force generation in BSM 4 weeks following surgery. Deletion of Nrp2 in mice already subjected to pBOO for 4 weeks showed increased contractility of tissues tested 6 weeks after surgery compared with nondeleted controls. Assessment of tissues from patients with urodynamically defined bladder outlet obstruction revealed reduced NRP2 levels in obstructed bladders with compensated compared with decompensated function, relative to asymptomatic controls. We conclude that downregulation of Nrp2 promotes BSM force generation. Neuropilin 2 may represent a novel target to restore contractility following obstruction.

Endogenous macrophage migration inhibitory factor reduces the accumulation and toxicity of misfolded SOD1 in a mouse model of ALS

Mutations in superoxide dismutase (SOD1) cause amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease characterized by the loss of upper and lower motor neurons in the brain and spinal cord. It has been suggested that the toxicity of mutant SOD1 results from its misfolding and accumulation on the cytoplasmic faces of intracellular organelles, including the mitochondria and endoplasmic reticulum (ER) of ALS-affected tissues. Recently, macrophage migration inhibitory factor (MIF) was shown to directly inhibit the accumulation of misfolded SOD1 and its binding to intracellular membranes, but the role of endogenous MIF in modulating SOD1 misfolding in vivo remains unknown. To elucidate this role, we bred MIF-deficient mice with SOD1(G85R) mice, which express a dismutase-inactive mutant of SOD1 and are considered a model of familial ALS. We found that the accumulation of misfolded SOD1, its association with mitochondrial and ER membranes, and the levels of sedimentable insoluble SOD1 aggregates were significantly higher in the spinal cords of SOD1(G85R)-MIF(-/-) mice than in their SOD1(G85R)-MIF(+/+) littermates. Moreover, increasing MIF expression in neuronal cultures inhibited the accumulation of misfolded SOD1 and rescued from mutant SOD1-induced cell death. In contrast, the complete elimination of endogenous MIF accelerated disease onset and late disease progression and shortened the lifespan of the SOD1(G85R) mutant mice. These findings indicate that MIF plays a significant role in the folding and misfolding of SOD1 in vivo, and they have implications for the potential therapeutic role of up-regulating MIF within the nervous system to modulate the selective accumulation of misfolded SOD1.

Research Findings on Overactive Bladder

Several physiopathologic conditions lead to the manifestation of overactive bladder (OAB). These conditions include ageing, diabetes mellitus, bladder outlet obstruction, spinal cord injury, stroke and brain injury, Parkinson's disease, multiple sclerosis, interstitial cystitis, stress and depression. This review has discussed research findings in human and animal studies conducted on the above conditions. Several structural and functional changes under these conditions have not only been observed in the lower urinary tract, but also in the brain and spinal cord. Significant changes were observed in the following areas: neurotransmitters, prostaglandins, nerve growth factor, Rho-kinase, interstitial cells of Cajal, and ion and transient receptor potential channels. Interestingly, alterations in these areas showed great variation in each of the conditions of the OAB, suggesting that the pathophysiology of the OAB might be different in each condition of the disease. It is anticipated that this review will be helpful for further research on new and specific drug development against OAB.

The role of macrophage migration inhibitory factor in mast cell-stimulated fibroblast proliferation and collagen production

Current clinical and translational studies have shown that mast cell plays a pivotal role in multiple fibrotic diseases including scleroderma. However, the lack of mature human mast cell culture model exhibits a major obstacle for further dissection of cytokines and signaling molecules required for mast cell mediated fibrosis in various diseases. Macrophage Migration Inhibitory Factor is a mast cell released pro-inflammatory cytokine which is deregulated in scleroderma patients and is also involved in non-scleroderma related fibrosis. In the current study, we successfully generated a practical and reliable human mast cell culture system with bone marrow CD34+ hematopietic precursors. The derivative mast cell is normal in terms of both morphology and function as manifested by normal degranulation. More importantly, we were able to show mast cell conditioned medium as well as MIF supplementation augments fibroblast proliferation and collagen synthesis. This positive regulatory effect of mast cell conditioned medium can be dampened by MIF antibody. In addition, MIF-knockdown significantly inhibits pro-fibrotic activities of CD34+ hematopietic precursor derived mast cells. These data strongly suggest that mast cell released MIF is required for mast cell mediated fibrogenic activities. The current manuscript seems to be the first mechanistic report showing the significance of MIF in mast cell mediated fibrosis, which may pave the way for the development of potential MIF-targeted therapy for fibrotic diseases to a further extent. Moreover, we strongly believe mast cell culture and differentiation model as well as corresponding genetic manipulation methodology will be helpful in characterizing novel mast cell based therapeutic targets.

Long-term caloric restriction in rats may prevent age related impairment of in vitro bladder function

PURPOSE

Bladder function is often impaired with aging. In other organs caloric restriction has had a prophylactic effect on the biological changes associated with aging. We tested the hypothesis that long-term caloric restriction can prevent age related impaired bladder function in the rat.

MATERIALS AND METHODS

Fisher 344 male rats were divided into 3 groups, including 16 young rats at age 6 months with free access to normal food, 15 old rats at age 25 to 28 months with free access to normal food and 16 old rats at age 25 to 28 months fed with normal food 3 days per week since age 6 weeks (caloric restriction). We performed frequency volume measurements, in vitro organ bath functional studies using full-thickness longitudinal detrusor strips, evaluation of muscarinic and purinergic receptor mRNA expression, and histological examination with Masson trichrome staining of bladder tissue.

RESULTS

Frequency volume changes did not significantly differ among the 3 groups. The old group fed normal food showed weaker contractile responses to carbachol and electrical field stimulation (especially in the cholinergic component), lower M3 receptor mRNA expression and higher collagen deposition compared to the young group. These age related bladder changes were milder in the old group with caloric restriction than in the old group fed normal food.

CONCLUSIONS

This study suggests that in the rat long-term caloric restriction has a preventive effect against age related functional and morphological bladder changes. These changes include impaired detrusor contractility that may be related to decreased expression of M3 receptors and to bladder wall fibrosis.

Macrophage migratory inhibitory factor promotes bladder cancer progression via increasing proliferation and angiogenesis

Macrophage migratory inhibitory factor (MIF) is a proinflammatory cytokine shown to promote tumorigenesis. Using the N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) model of bladder cancer, we previously showed that MIF knockout mice display decreased angiogenesis and invasion compared with wild-type. This study examines the role of MIF in bladder cancer via use of oral inhibitors of MIF. In vitro, high-grade bladder cancer cells were treated with recombinant human MIF +/- (rhMIF+/-) inhibitor. Measurements included cell counts, proliferation by (3)H-thymidine incorporation (TdR), extracellular signal-regulated kinase (ERK) phosphorylation by western blot analysis, messenger RNA (mRNA) expression by quantitative PCR and protein secretion by enzyme-linked immunosorbent assay. Treatment with rhMIF increased ERK phosphorylation, cell counts, TdR and mRNA expression and protein secretion of vascular endothelial growth factor, which were blocked by specific inhibitors of ERK and MIF. In vivo, 3-month-old male C57Bl/6 mice were given BBN for 22 and 16 weeks in study 1 and study 2, respectively. Mice (n = 8-10 per group) were gavaged with vehicle or doses of MIF inhibitors daily from weeks 16-22 in both studies. Average bladder weights, reflecting tumor mass, tumor stage/burden, mitotic rate and proliferation indices, and microvessel densities were reduced in inhibitor groups versus controls. In summary, MIF promotes bladder cancer via increasing cell proliferation and angiogenesis and oral inhibitors of MIF may prove useful in treatment of this disease.

Deletion of macrophage migration inhibitory factor worsens stroke outcome in female mice

Sex is an important factor in the response to ischemic insults in both the laboratory and the clinic. Inflammation and cell death are points where sex-specific pathways diverge in stroke, and serum estrogen level status affect the response to inflammation. The cytokine macrophage migration inhibitory factor (MIF) is detrimental in experimental stroke models in male animals. However MIF is known to have sex-specific actions on inflammation and wound healing. The role of MIF in the ischemic female brain has not been evaluated. A transient middle cerebral artery occlusion (MCAO/90min) model was used to induce stroke in male, intact female, and ovariectomized female wildtype (WT) and MIF knockout (KO) mice. Infarct size was quantified 72h after stroke. Protein and cytokine levels were assessed post stroke. Female MIF KO mice had significantly larger strokes compared to WT females (mean hemispheric infarct±SEM: 63%±2% versus 29%±3%; n=8; p<0.05). Ovariectomized female MIF KO mice also had larger infarcts than ovariectomized WT littermates (70%±3% versus 47%±4%; n=11; p<0.05). In males, however, infarct size was equivalent between MIF KO and WT mice (63%±2% versus 67%±3%; n=9; p=0.25). There were no significant differences in cytokine levels at 6h post-infarct between mice of either genotype in brain. MIF KO females displayed more microglial activation (ionized calcium binding adaptor molecule 1 (Iba1) immunofluorescence) after stroke than did WT mice or MIF KO males. The larger infarcts in MIF KO females were associated with an early increase in mitochondrial localization of Jun activation domain-binding protein 1 (JAB1). Loss of MIF exacerbated injury in the female brain after experimental stroke, which was independent of changes in pro-inflammatory cytokine levels. This response is sex-specific, and is in part independent of physiological serum levels of estrogen.

Macrophage migration inhibitory factor deficiency protects pancreatic islets from cytokine-induced apoptosis in vitro

During pathogenesis of diabetes, pancreatic islets are exposed to high levels of cytokines and other inflammatory mediators that induce deterioration of insulin-producing beta cells. Macrophage migration inhibitory factor (MIF) plays a key role in the onset and development of several immunoinflammatory diseases and also controls apoptotic cell death. Because the occurrence of apoptosis plays a pathogenetic role in beta cell death during type 1 diabetes development and MIF is expressed in beta cells, we explored the influence of MIF deficiency on cytokine-induced apoptosis in pancreatic islets. The results indicated clearly that elevated MIF secretion preceded C57BL/6 pancreatic islets death induced by interferon (IFN)-γ + tumour necrosis factor (TNF)-α + interleukin (IL)-1β. Consequently, MIF-deficient [MIF-knock-out (KO)] pancreatic islets or islet cells showed significant resistance to cytokine-induced death than those isolated from C57BL/6 mice. Furthermore, upon exposure to cytokines pancreatic islets from MIF-KO mice maintained normal insulin expression and produced less cyclooxygenase-2 (COX-2) than those from wild-type C57BL6 mice. The final outcome of cytokine-induced islet apoptosis in islets from wild-type mice was the activation of mitochondrial membrane pore-forming protein Bcl-2-associated X protein and effector caspase 3. In contrast, these apoptotic mediators remained at normal levels in islets from MIF-KO mice suggesting that MIF absence prevented initiation of the mitochondrial apoptotic pathway. Additionally, the protection from apoptosis was also mediated by up-regulation of prosurvival kinase extracellular-regulated kinase 1/2 in MIF-KO islets. These data indicate that MIF is involved in the propagation of pancreatic islets apoptosis probably via nuclear factor-κB and mitochondria-related proteins.

Beta cell function: the role of macrophage migration inhibitory factor

During evolution, beta cells adapted to a sole aim: the production and stimulus-dependent secretion of insulin. This acquired specificity was accompanied by a loss of protection mechanisms predisposing beta cell to a high vulnerability. Among beta cell-damaging molecules, a new one has been identified recently: macrophage migration inhibitory factor (MIF). MIF was at first designated as a T-cell product that inhibits random movement of macrophages. Over the years, the number of functions attributed to this protein increased significantly, positioning MIF at the top of inflammatory cascade in the combat against infection and in immunoinflammatory and autoimmune diseases. This exceptionally versatile molecule regulates insulin secretion in physiological conditions, while in pathological states it alters beta cell function and induces their apoptosis or necrosis and affects beta cell neoplasia.

MIF, CD74 and other partners in kidney disease: tales of a promiscuous couple

Macrophage migration inhibitory factor (MIF) is increased in kidney and urine during kidney disease. MIF binds to and activates CD74 and chemokine receptors CXCR2 and CXCR4. CD74 is a protein trafficking regulator and a cell membrane receptor for MIF, D-dopachrome tautomerase (D-DT/MIF-2) and bacterial proteins. MIF signaling through CD74 requires CD44. CD74, CD44 and CXCR4 are upregulated in renal cells in diseased kidneys and MIF activation of CD74 in kidney cells promotes an inflammatory response. MIF or CXCR2 targeting protects from experimental kidney injury, CD44 deficiency modulates kidney injury and CXCR4 activation promotes glomerular injury. However, the contribution of MIF or MIF-2 to these actions of MIF receptors has not been explored. The safety and efficacy of strategies targeting MIF, CD74, CD44 and CXCR4 are under study in humans.

Macrophage migration inhibitory factor deficiency protects pancreatic islets from palmitic acid-induced apoptosis

As a result of chronic exposure to high levels of free fatty acids, glucose and inflammatory mediators β-cell apoptosis occurs at the end stage of obesity-associated type 2 diabetes (T2D). One potentially deleterious molecule for β-cell function associated with T2D and obesity in humans is macrophage migration inhibitory factor (MIF). Therefore, the aim of this study was to explore MIF expression in vivo during development of obesity and insulin resistance in high-fat diet (HFD)-fed C57BL/6 mice and whether MIF inhibition could affect β-cell apoptosis and dysfunction induced by palmitic acid (PA) in vitro. Indeed, increase in systemic and locally produced MIF correlated well with the weight gain, triglyceride upregulation, glucose intolerance and insulin resistance, which developed in HFD-fed mice. In in vitro settings PA dose-dependently induced MIF secretion before apoptosis development in islets. Further, mif gene deletion, mRNA silencing or protein inhibition rescued β-cells from PA-induced apoptosis as measured by MTT assay and histone-DNA enzyme linked immuno sorbent assay. Protection from induced apoptosis was mediated by altered activation of caspase pathway and correlated with changes in the level of Bcl-2 family members. Further, MIF inhibition conveyed a significant resistance to PA-induced downregulation of insulin and PDX-1 expression and ATP content. However, β-cell function was not entirely preserved in the absence of MIF judging by low glucose oxidation and depolarized mitochondrial membrane. In conclusion, the observed considerable preservation of β-cells from nutrient-induced apoptosis might implicate MIF as a potential therapeutic target in the later stage of obesity-associated T2D.

Detrusor underactivity: a plea for new approaches to a common bladder dysfunction

AIMS

Detrusor underactivity (DU) is defined by the International Continence Society as a contraction of reduced strength and/or duration resulting in prolonged or incomplete emptying of the bladder but has yet received only little attention. The purpose of this report is to summarize the ICI-RS meeting in Bristol in 2010 exploring current knowledge on DU and outline directions for future research.

METHODS

A think tank discussion was held and the summary of discussions was presented to all ICI-RS participants. This report is based on the final discussions.

RESULTS

The understanding of the pathophysiology, epidemiology, assessment, and treatment of DU remains rudimentary. DU is defined by pressure-flow analysis but no consensus exists regarding which of the available formulae should be used for quantification of detrusor work. DU is likely to be multifactorial. Aging causes a decay in detrusor activity but other concomitant causes, either myogenic or neurogenic, may aggravate the problem resulting in decrease of detrusor contractility. No effective pharmacotherapy for the condition exists. Only a few surgical therapeutic strategies have been explored, such as neuromodulation and skeletal muscle myoplasties. Consequently, the management of affected individuals remains unsatisfactory.

CONCLUSIONS

Future directions recommended by the ICI-RS panel include assessment of pathogenesis by developing novel animal models in addition to new non-invasive tests allowing longitudinal trials. Furthermore, optimizing the existing evaluation algorithms to support standard testing for DU and further epidemiological studies to quantify the size of the problem are required for the development of future treatment modalities.

The Relaxing Effect of α-Defensin 1 on the Adrenergic Responses of Rat Bladder

Defensins, cysteine-rich cationic polypeptides released from neutrophils, are known to have powerful antimicrobial properties. In this study, we sacrificed 30 rats to investigate the effects of α-defensin 1 on detrusor muscle contractions in isolated rat bladder. From the experiments we found relaxing effects of α-defensin 1 on the contractions induced by phenylephrine (PE) but not by bethanechol (BCh) in the detrusor smooth muscles. To determine the mechanisms of the effects of α-defensin 1, the changes of effects on PE-induced contraction by α-defensin 1 pretreatment were observed after pretreatment of Rho kinase inhibitor (Y-27632), protein kinase C (PKC) inhibitor (Calphostin C), potent activator of PKC (PDBu; phorbol 12,13-dibutyrate), and NF-κB inhibitors (PDTC; pyrrolidinedithiocarbamate and sulfasalazine). The contractile responses of PE (10(-9)~10(-4) M) were significantly decreased in some concentrations of α-defensin 1 (5×10(-9) and 5×10(-8) M). When strips were pretreated with NF-κB inhibitors (PDTC and sulfasalazine; 10(-7)~10(-6) M), the relaxing responses by α-defensin 1 pretreatment were disappeared. The present study demonstrated that α-defensin 1 has relaxing effects on the contractions of rat detrusor muscles, through NF-κB pathway. Further studies in vivo are required to clarify whether α-defensin 1 might be clinically related with bladder dysfunction by inflammation process.

Bladder cancer in the elderly: clinical outcomes, basic mechanisms, and future research direction

The association between aging and cancer is well exemplified by bladder cancer: with advancing age, the risk of developing bladder cancer increases, and patients' clinical presentation and outcomes worsen. Care for elderly patients with bladder cancer requires specific knowledge of many key geriatric clinical issues in order to determine optimal treatment plans. While numerous studies have tried to address the role of urologic intervention for elderly patients with bladder cancer, many studies fail to incorporate a component of true functional assessment. Evaluation tools that incorporate comorbidities, disabilities and functional status will need to be developed, as chronological age is a poor predictor of treatment outcomes. Additionally, further research is necessary to better understand the basic mechanisms that predispose elderly patients to develop this costly and life-threatening disease. This Review examines the current literature evaluating the clinical and mechanistic interactions between aging and bladder cancer, and suggests the formulation of a research agenda to address the issues raised.

Recruitment of bone marrow derived cells to the bladder after bladder outlet obstruction

PURPOSE

Bladder fibrosis is an undesired end point of partial bladder outlet obstruction. In fibrotic disease of the lung, kidney, skin and heart chemokines recruit bone marrow derived cells to injured tissue. Blockade of chemokines like CCL2 results in decreased fibrosis in other organs. To our knowledge we present the first report of bone marrow derived cell recruitment to the bladder in a murine bladder outlet obstruction model.

MATERIALS AND METHODS

We lethally irradiated WT female mice and reconstituted their bone marrow using fetal liver cells from transgenic mice ubiquitously expressing green fluorescent protein. Periurethral collagen injection was used for bladder outlet obstruction. Obstruction was assessed by urodynamics, and bladder and kidney histological changes. Bladders were harvested 1 to 12 weeks after bladder outlet obstruction and compared to those in nonobstructed controls. The chemokine CCL2 was compared between obstructed and nonobstructed mice with reverse transcriptase-polymerase chain reaction. Green fluorescent protein expressing bone marrow derived cells were identified with immunohistochemistry and fluorescence activated cell sorting.

RESULTS

Bladders showed histological and urodynamic changes consistent with obstruction. CCL2 induction increased after obstruction compared to that in controls. After obstruction bone marrow derived cells were present in the urothelial and stromal layers. Activated epidermal growth factor receptor was found in cells associated with bone marrow derived cells.

CONCLUSIONS

Bone marrow derived cells are recruited to the bladder by bladder outlet obstruction and are present in the urothelial and stromal layers. Stromal bone marrow derived cells may have a role in hypertrophy and fibrosis. Further study of the recruitment and function of bone marrow derived cells in the bladder may provide potential targets for antifibrotic therapy.

Suppression of bladder oxidative stress and inflammation by a phytotherapeutic agent in a rat model of partial bladder outlet obstruction

PURPOSE

Ischemia/reperfusion injury is a major etiological factor in the progression of bladder dysfunction after partial bladder outlet obstruction and it is partly mediated by the generation of free radicals. The phytotherapeutic agent Eviprostat, a popular treatment for benign prostatic hyperplasia in Japan and Germany, has antioxidant and anti-inflammatory activity. We investigated the effect of Eviprostat on oxidative stress and inflammation in bladder dysfunction in a bladder outlet obstruction rat model.

MATERIALS AND METHODS

Bladder outlet obstruction was surgically induced in male rats by placing a rubber ring around the urethra. Rats with bladder outlet obstruction were administered daily oral Eviprostat or vehicle, while sham operated animals were treated with vehicle. On day 6 after surgery bladder weight, oxidative stress markers and proinflammatory cytokine levels as a measure of bladder inflammation, were determined and histological alterations noted. Functional contractility studies were performed with longitudinal bladder strips.

RESULTS

Bladder outlet obstruction led to a significant increase in bladder weight, oxidative stress markers and proinflammatory cytokine levels. Eviprostat significantly suppressed these increases without affecting bladder weight. Histological analysis showed increased detrusor muscle hypertrophy and increased numbers of collagen fibers with accompanying inflammatory infiltration in the bladder of vehicle treated bladder outlet obstruction animals. Eviprostat treatment was associated with suppression of these changes. Decreased responses of obstructed bladder strips to electrical stimulation and KCl were ameliorated by Eviprostat treatment.

CONCLUSIONS

Eviprostat mediated decrease of the increased oxidative stress and bladder inflammation caused by bladder outlet obstruction may contribute to the protection of bladder function.

Estrogen administration attenuates bladder outlet obstruction induced oxidative stress in the female rabbit

AIMS

Estrogen administration to female rabbits induces a functional hypertrophy of the bladder. The aim of this study was to investigate whether supplementation of estrogen in the female rabbit with partial bladder outlet obstruction (PBOO) would affect the severity of bladder dysfunction.

METHODS

We surgically created PBOO in female New Zealand White rabbits. Group 1 included sham operated rabbits which served as controls. Group 2 received PBOO without estrogen treatment. Group 3 received estrogen treatment after PBOO. Group 4 received estrogen pretreatment before PBOO. The bladders were then removed for contractile, biochemical, and protein expression studies. There were four rabbits per group.

RESULTS

(1) PBOO resulted in significant decreases in the contractile responses to all forms of stimulation (field stimulation [FS], carbachol, KCl, ATP). Both pretreatment and post-treatment with estrogen resulted in significantly increased contractile responses to all forms of stimulation, although the responses were still lower than control. (2) PBOO resulted in a significant decrease in the activity of choline acetyltransferase (ChAT). Both pretreatment and post-treatment with estrogen resulted in significant increases in ChAT activity back toward control levels. (3) PBOO resulted in significant increases in both protein oxidation and nitration; both pretreatment and post-treatment with estrogen significantly reduced oxidation and nitration toward control levels.

CONCLUSIONS

Estrogen pretreatment and post-treatment in the female rabbit ameliorated contractile and biochemical dysfunctions associated with PBOO. This improvement is likely due to reduced oxidative stress. As expected, pretreatment was generally more effective than post-treatment.

Transcriptomic analysis of intestinal fibrosis-associated gene expression in response to medical therapy in Crohn's disease

BACKGROUND

Glucocorticoids and monoclonal antibodies to tumor necrosis factor reduce inflammation in Crohn's disease (CD). Rapid luminal healing, however, may promote intestinal stricture formation. The aim of this study was to examine fibrosis-associated gene expression in the intestine of patients with CD and correlate expression levels with prior medical therapies.

METHODS

In all, 37 patients with stricturing CD and 18 non-CD controls underwent a transmural biopsy at the time of elective intestinal resection. Quantitative real-time polymerase chain reaction (PCR) was conducted to determine differential mRNA expression of TGF-beta(1), Smad-7, CTGF, collagen-1alpha, fibronectin, BMP-7, and MIF. Intestinal fibroblasts were treated in vitro with dexamethasone.

RESULTS

Relative to control, strictured CD intestinal tissue expressed increased TGF-beta(1), CTGF, collagen-1alpha, and BMP-7 (all P < 0.05). TGF-beta(1) gene expression positively correlated with the expression of its downstream targets (all P < 0.001). Preoperative infliximab exposure was not associated with increased expression in any of the target genes nor did the number of infliximab infusions correlate with gene expression. The number of cycles of corticosteroid treatment preoperatively was positively associated with CTGF (r = 0.486, P = 0.016) and MIF (r = 0.524, P = 0.009) expression. Intestinal fibroblasts treated in vitro with dexamethasone upregulated CTGF expression (P = 0.023).

CONCLUSIONS

Exposure to infliximab does not appear to induce a profibrotic transcriptional response in the CD intestine. Previous corticosteroid treatment is associated with increased expression of CTGF and MIF. Treating intestinal fibroblasts in vitro with steroids upregulates CTGF expression.

Null mutation for macrophage migration inhibitory factor (MIF) is associated with less aggressive bladder cancer in mice

Background

Inflammatory cytokines may promote tumorigenesis. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine with regulatory properties over tumor suppressor proteins involved in bladder cancer. We studied the development of bladder cancer in wild type (WT) and MIF knockout (KO) mice given N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN), a known carcinogen, to determine the role of MIF in bladder cancer initiation and progression.

Methods

5-month old male C57Bl/6 MIF WT and KO mice were treated with and without BBN. Animals were sacrificed at intervals up to 23 weeks of treatment. Bladder tumor stage and grade were evaluated by H&E. Immunohistochemical (IHC) analysis was performed for MIF and platelet/endothelial cell adhesion molecule 1 (PECAM-1), a measure of vascularization. MIF mRNA was analyzed by quantitative real-time polymerase chain reaction.

Results

Poorly differentiated carcinoma developed in all BBN treated mice by week 20. MIF WT animals developed T2 disease, while KO animals developed only T1 disease. MIF IHC revealed predominantly urothelial cytoplasmic staining in the WT control animals and a shift toward nuclear staining in WT BBN treated animals. MIF mRNA levels were 3-fold higher in BBN treated animals relative to controls when invasive cancer was present. PECAM-1 staining revealed significantly more stromal vessels in the tumors in WT animals when compared to KOs.

Conclusion

Muscle invasive bladder cancer with increased stromal vascularity was associated with increased MIF mRNA levels and nuclear redistribution. Consistently lower stage tumors were seen in MIF KO compared to WT mice. These data suggest that MIF may play a role in the progression to invasive bladder cancer.

Geriatric syndromes: clinical, research, and policy implications of a core geriatric concept

Geriatricians have embraced the term "geriatric syndrome," using it extensively to highlight the unique features of common health conditions in older people. Geriatric syndromes, such as delirium, falls, incontinence, and frailty, are highly prevalent, multifactorial, and associated with substantial morbidity and poor outcomes. Nevertheless, this central geriatric concept has remained poorly defined. This article reviews criteria for defining geriatric syndromes and proposes a balanced approach of developing preliminary criteria based on peer-reviewed evidence. Based on a review of the literature, four shared risk factors-older age, baseline cognitive impairment, baseline functional impairment, and impaired mobility-were identified across five common geriatric syndromes (pressure ulcers, incontinence, falls, functional decline, and delirium). Understanding basic mechanisms involved in geriatric syndromes will be critical to advancing research and developing targeted therapeutic options, although given the complexity of these multifactorial conditions, attempts to define relevant mechanisms will need to incorporate more-complex models, including a focus on synergistic interactions between different risk factors. Finally, major barriers have been identified in translating research advances, such as preventive strategies of proven effectiveness for delirium and falls, into clinical practice and policy initiatives. National strategic initiatives are required to overcome barriers and to achieve clinical, research, and policy advances that will improve quality of life for older persons.

Detrusor Underactivity: Clinical Features and Pathogenesis of an Underdiagnosed Geriatric Condition

Urinary incontinence and other lower urinary tract symptoms exert a major influence on the health and independence of frail older people. Detrusor underactivity (DU) is defined as a contraction of reduced strength and/or duration, resulting in prolonged bladder emptying and/or a failure to achieve complete bladder emptying within a normal time span. DU may influence the clinical presentation and impede the therapy of disorders as common and as disparate as detrusor overactivity, urinary retention, and benign prostatic hyperplasia. Urodynamically, nearly two-thirds of incontinent nursing home residents exhibit DU. The clinical diagnosis of DU when present alone or in association with other bladder conditions such as detrusor overactivity (detrusor hyperactivity with impaired contractility (DHIC)) is challenging, because symptoms lack adequate precision. A catheterized and increasingly noninvasive ultrasound-based postvoid residual assessment allows a bedside diagnosis of retention and may suggest the presence of DU in individuals (mostly women) with a low likelihood of bladder outlet obstruction (BOO). Nevertheless, it cannot differentiate primary DU from retention secondary to BOO. The management of individuals with DHIC remains unsatisfactory, because antispasmodic anticholinergic medications may worsen retention, whereas bethanechol does not improve bladder emptying. Human detrusor biopsies reveal axonal degeneration, muscle loss, and fibrosis in DU. Animal studies suggest that multiple risk factors, including retention itself, lack of estrogen, infection, inflammation, and aging, may contribute to DU. Priority areas for future research include efforts to facilitate clinical nonurodynamic diagnosis of probable DU plus translational research designed to address the pathogenesis of this complex multifactorial geriatric syndrome.