INCREASED URINARY HYALURONIC ACID AND INTERSTITIAL CYSTITIS

A high molecular weight hyaluronic acid biphasic dispersion as potential therapeutics for interstitial cystitis

Interstitial cystitis (IC) is a progressive bladder disease characterized by increased urothelial permeability, inflammation of the bladder with abdominal pain. While there is no consensus on the etiology of the disease, it was believed that restoring the barrier between urinary solutes and (GAG) urothelium would interrupt the progression of this disease. Currently, several treatment options include intravesical delivery of hyaluronic acid (HA) and/or chondroitin sulfate solutions, through a catheter to restore the urothelial barrier, but have shown limited success in preclinical, clinical trials. Herein we report for the first time successful engineering and characterization of biphasic system developed by combining cross‐linked hyaluronic acid and naïve HA solution to decrease inflammation and permeability in an in vitro model of interstitial cystitis. The cross‐linking of HA was performed by 4‐arm‐polyethyeleneamine chemistry. The HA formulations were tested for their viscoelastic properties and the effects on cell metabolism, inflammatory markers, and permeability. Our study demonstrates the therapeutic effects of different ratios of the biphasic system and reports their ability to increase the barrier effect by decreasing the permeability and alteration of cell metabolism with respect to relative controls. Restoring the barrier by using biphasic system of HA therapy may be a promising approach to IC.

Urine and serum glycosaminoglycan levels in the diagnosis of urological diseases and conditions: A narrative review of the literature

Glycosaminoglycans (GAGs) are sulfated, negatively charged polysaccharides produced in almost every cell of the human body. As GAGs are extracellularly localized, the changes in body fluids such as blood and urine may reflect pathological changes in the urinary system as observed in other pathologies. In this review, we determined the potential of urinary and/or serum GAG levels as a marker for kidney and urothelial system diseases. We performed a search in the PubMed, MEDLINE, and ScienceDirect databases until September 30, 2019. A number of studies reported changes in the urinary and/or plasma GAG levels or composition in urological diseases and conditions, such as renal cell carcinoma, kidney stone, bladder carcinoma, and overactive bladder. GAGs were found to have a predictive biomarker potential that could be limited by generalizability concerns.

High molecular weight hyaluronic acid: a two-pronged protectant against infection of the urogenital tract?

OBJECTIVES

Recurrent urinary tract infections are associated with uropathogenic Escherichia coli (UPEC) ascending and infecting the urinary tract. Antibiotics provide only symptomatic relief, not prevent recurrence. Clinical evidence suggests that intravesical glycosaminoglycan therapy, such as hyaluronic acid (HA), helps reduce UTI recurrence. This has been investigated here using in vitro systems modelling the urogenital tract tissues.

METHODS

RT4 bladder cells were preconditioned with high molecular weight HA (> 1500 kDa) at 2 mg mL-1 and challenged with UPEC to analyse barrier protection and bacterial adherence. Untreated and HA-preconditioned VK2 E6/E7 vaginal cells were challenged with E. coli flagellin (50 ng mL-1) to mimic bacterial challenge, and media analysed for lipocalin-2, human β-defensin 2 and interleukin-8 by ELISA. Experiments were repeated after siRNA knockdown of Toll-like receptors 2, 4 and 5, and CD44 to investigate signalling.

RESULTS

Microscopic analyses showed reduced bacterial adherence and urothelial disruption with HA, suggesting that HA functions as a barrier protecting the epithelium from bacterial infection. Cells treated with HA and flagellin simultaneously produced more of the host antimicrobial peptide LCN2 and pro-inflammatory IL-8 (P < 0.05) compared to the no HA/flagellin challenges. Increased gene expression of DEFB4 (P < 0.05), but not the hBD2 peptide, was observed in the HA/flagellin-challenged cells.

CONCLUSION

These data suggest that exogenous HA has potential to protect the urogenital epithelia from UPEC infection via a two-pronged approach that involves the physical enhancement of the epithelial barrier and augmentation of its innate immune response.

A Pilot Open Label Study of Cystoprotek® in Interstitial Cystitis

Interstitial cystitis (IC) is a disorder of the urinary bladder characterized by urgency, frequency, nocturia and suprapubic pain. IC occurs primarily in women and symptoms are exacerbated by stress, ovulatory hormones and certain foods. IC pathogenesis is unknown, but the most consistent findings involve some dysfunction of the bladder glycosaminoglycan (GAG) protective layer and a high number of activated bladder mast cells. There is no effective therapy even through intravesical administration of dimethylsulfoxide (DMSO) or oral pentosanpolysulfate (PPS) have had variable success. A dietary supplement, CystoProtek®, was formulated with the natural GAG components chondroitin sulfate and sodium hyaluronate to provide urothelial cytoprotection, together with the flavonoid quercetin that has anti-inflammatory properties and inhibits activation of mast cells. Thirty-seven female patients diagnosed by the NIDDK criteria who had failed all forms of therapy took six softgel CystoProtek® capsules per day for 6 months. Global assessment scale was reduced from 9.0 ± 2.9 to 4.3 ± 2.1 (p <0.05); moreover, the O'Leary/Sant Symptom Index decreased from 16.3 ± 3.1 to 6.9 ± 4.2 (p <0.05) and the Problem Index from 13.1 ± 3.7 to 5.4 ± 4.0 (p <0.05). These results are very promising and warrant a larger study that may permit further analyses with respect to other, especially atopic, comorbid diseases.

Hyaluronic acid decreases IL-6 and IL-8 secretion and permeability in an inflammatory model of interstitial cystitis

Hyaluronic acid (HA) has received a lot of attention recently as a biomaterial with applications in wound healing, drug delivery, vascular repair and cell and/or gene delivery. Interstitial cystitis (IC) is characterised by an increase in the permeability of the bladder wall urothelium due to loss of the glycosaminoglycan (GAG) layer. The degradation of the urothelium leads to chronic pain and urinary dysfunction. The aetiology of the degradation of the GAG layer in this instance is currently unknown. At a clinical level, GAG replacement therapy using a HA solution is currently utilised as a treatment for IC. However, there is a significant lack of data on the mechanism of action of HA in IC. The current study investigates the mechanistic effect of clinically relevant HA treatment on an in vitro model of IC using urothelial cells, examining cytokine secretion, GAG secretion and trans-epithelial permeability. This study demonstrates that HA can significantly decrease induced cytokine secretion (4-5 fold increase), increase sulphated GAG production (2-fold increase) and without altering tight junction expression, decrease trans-epithelial permeability, suggesting that the HA pathway is a clinical target and potential treatment vector.

Intravesical hyaluronic acid for interstitial cystitis/painful bladder syndrome: a comparative randomized assessment of different regimens

OBJECTIVES

To compare the clinical effectiveness of different regimens of intravesical hyaluronic acid instillation for patients with interstitial cystitis/painful bladder syndrome.

METHODS

A total of 60 patients (age 16-77 years) diagnosed with interstitial cystitis/painful bladder syndrome were enrolled in this prospective, randomized study. A total of 30 patients were assigned to receive four weekly intravesical instillations of 40 mg of hyaluronic acid followed by five monthly instillations (hyaluronic acid-9 group). Another 30 patients received 12 intravesical instillations of 40 mg hyaluronic acid every 2 weeks (hyaluronic acid-12 group). Symptomatic changes after hyaluronic acid treatments were assessed using Interstitial Cystitis Symptom and Problem Indexes, pain visual analog scale, functional bladder capacity, frequency and nocturia in voiding diary, maximum flow rate, voided volume, postvoid residual volume, and Quality of Life Index at 1, 3 and 6 months.

RESULTS

Of the 60 patients, 59 were evaluable at the end of the study. The Interstitial Cystitis Symptom Index, Interstitial Cystitis Problem Index and total score, pain visual analog scale, functional bladder capacity, maximum flow rate, and Quality of Life Index improved significantly after 6 months in both groups. The frequency and voided volume improved significantly only in the hyaluronic acid-12 group. However, patients with moderate and marked improvement were clinically similar in both groups. The measured variables did not differ between the two groups over the course of the study.

CONCLUSION

No significant difference was noted in the therapeutic effect between two hyaluronic acid instillation regimens for treatment of interstitial cystitis/painful bladder syndrome patients. Both groups showed significant improvement in symptom scores and Quality of Life Index.

Interstitial cystitis: bladder pain and beyond

BACKGROUND

Interstitial cystitis is characterized by over 6 months of chronic pain, pressure and discomfort felt in the lower pelvis or bladder. It is often relieved with voiding, along with daytime frequency and nocturia in the absence of a urinary tract infection. Interstitial cystitis occurs primarily in females including adolescents and its diagnosis is still one of exclusion. It is now recognized as a serious medical condition associated with significant disability.

OBJECTIVE

The aim of this paper was to review the pathogenesis and treatment of interstitial cystitis with emphasis on new pathogenetic trends and therapeutic modalities.

METHODS

About 713 mostly original papers were reviewed in Medline from 1990 to August. 2008. All authors independently reviewed the literature. Large, double-blind, placebo-controlled, clinical trials were few and the medical histories of the patients used varied considerably making conclusions difficult. Promising pilot trials turned out mostly negative on follow-up.

RESULTS

Increasing evidence of co-morbid diseases, neurogenic inflammation and the effect of stress are promising as new targets for pathophysiology. No new effective treatments have emerged. Oral pentosanpolysulfate, amitriptyline, hydroxyzine and quercetin, as well as intravesical heparin/bicarbonate/lidocaine solutions, are still used with variable success. Some pilot open-label trials presented encouraging findings.

CONCLUSION

Interstitial cystitis contributes substantially to chronic pelvic pain and to poor quality of life. Oral or intravesical administration of solutions containing sodium hyaluronate, chondroitin sulfate and quercetin to both reduce bladder inflammation and 'replenish' the glycosaminoglycan layer should be tried. There is a clear need for therapeutic modalities. New potential translational research areas are suggested.

Urinary glycosaminoglycans as biomarker for urothelial injury: is it possible to discriminate damage from recovery?

OBJECTIVES

The glycosaminoglycan (GAG) layer is referred to as a bladder protective factor. We reproduced an experimental model of urothelial damage to assess GAG metabolism in the process of injury and recovery of the urothelium.

METHODS

Wistar female rats were bladder catheterized and instilled with either protamine sulfate (PS groups) or sterile saline (control groups). At different days after the procedure, 24-hour urine samples were obtained. The urinary levels of hyaluronic acid (HA) and sulfated glycosaminoglycan were determined in all groups and in nonmanipulated rats (day 0). Additionally, sulfated-GAG synthesis was assessed by the incorporation of [(35)S]-inorganic sulfate. The bladders were analyzed by histochemical staining for HA and immunofluorescence for heparin sulfate and syndecan-4.

RESULTS

Urinary HA and sulfated-GAG were elevated after PS injection (P <0.05). A greater concentration of [(35)S]-labeled GAG in the PS group animals on the fifth day and, especially, on the seventh day represented increased GAG synthesis at these periods (P <0.05). Bladder sections from the PS group animals on day 1 showed a greater amount of HA in the urothelium. PS instillation damaged the urothelium layer of heparin sulfate and syndecan-4 seen in the control animals. On day 5, patchy areas of a restored layer were seen, and, on day 7, this layer had completely regenerated.

CONCLUSIONS

Urinary GAG cannot differentiate urothelial damage from recovery. Elevated levels of urinary GAG can result from either desquamation of the surface cell GAG layer or increased GAG synthesis to regenerate the damaged urothelium.

Treatment approaches for painful bladder syndrome/interstitial cystitis

Painful bladder syndrome/interstitial cystitis (PBS/IC) is a disease of unknown aetiology, characterised by severe pressure and pain in the bladder area or lower pelvis that is frequently or typically relieved by voiding, along with urgency or frequency of urination in the absence of urinary tract infections. PBS/IC occurs primarily in women, is increasingly recognised in young adults, and may affect as many as 0.1-1% of adult women. PBS/IC is often comorbid with allergies, endometriosis, fibromyalgia, irritable bowel syndrome and panic syndrome, all of which are worsened by stress. As a result, patients may visit as many as five physicians, including family practitioners, internists, gynaecologists, urologists and pain specialists, leading to confusion and frustration. There is no curative treatment; intravesical dimethyl sulfoxide, as well as oral amitriptyline, pentosan polysulfate and hydroxyzine have variable results, with success more likely when these drugs are given together. Pilot clinical trials suggest that the flavonoid quercetin may be helpful. Lack of early diagnosis and treatment can affect outcomes and leads to the development of hyperalgesia/allodynia.

Urinary protein expression patterns in children with sleep-disordered breathing: Preliminary findings

BACKGROUND

Obstructive sleep apnea (OSA) is the most common form of sleep-disordered breathing, with almost 15 million Americans affected and many more at risk. Current diagnostic approach to OSA requires polysomnography, which is laborious, onerous, and time-consuming. There is ample evidence that inflammatory responses to the perturbations associated with OSA trigger a variety of genes and signaling cascades that ultimately lead to end-organ injury and changes in kidney function and protein expression. The aim of this study was therefore to analyze proteins in human urine and assess whether differential expression of particular proteins is associated with the presence of OSA.

METHODS

Eleven OSA and 11 control children between the ages of three and 14 (males=17; females=5) underwent overnight sleep studies followed by a first-morning urine sample. Proteomic analysis of urine samples yielded a unique map of proteins, of which, five spots were selected for further analysis due to their significant intensity differences between OSA and control groups.

RESULTS

Mass spectrometry followed by peptide mass fingerprinting conclusively identified four of the five spots as gelsolin, perlecan (a heparan sulfate proteoglycan), albumin, and immunoglobulin (P<0.05 and protein scores>67).

CONCLUSIONS

Overall, increased expression of gelsolin and perlecan in the urinary proteome of children with OSA suggests that the episodic hypoxia associated with OSA may lead to changes in protein permeability or alternatively to increased catabolism of these proteins and their excretion in urine.

Current status in the pharmacological management of interstitial cystitis

Interstitial cystitis is a clinical condition occurring predominantly in women characterised by irritative voiding symptoms in the form of urinary frequency, urgency and pain. Patient symptoms have the potential to significantly affect quality of life, posing a challenge to some to perform activities of daily living. Those who reach an eventual diagnosis of interstitial cystitis have typically done so through an emotionally charged and circuitous route, the product of numerous physician encounters and stigmatising experiences. As such, these patients require considerate care. Overall, current pharmacological agents for the treatment of those with interstitial cystitis, provide a measure of symptomatic benefit, however, a universally effective regimen remains to be reported. As a definitive disease aetiopathogenesis is not fully determined, trials of pharmacological therapy are ongoing.

Interstitial cystitis and pelvic floor dysfunction: a comprehensive review

Interstitial cystitis is a clinical condition occurring predominantly in women and is characterized by urinary frequency, urgency, and pain. Patient symptoms have the potential to significantly affect quality of life, posing a challenge to some to perform activities of daily living. This article comprehensively reviews the literature on the epidemiology, etiology, evaluation, and treatment of interstitial cystitis, and considers commonly associated pelvic floor dysfunction.

Glycosaminoglycan profile in bladder and urethra of castrated rats treated with estrogen, progestogen, and raloxifene

OBJECTIVE

This study was undertaken to evaluate the action of conjugated equine estrogens alone, medroxyprogesterone, the combination of these estrogens with progestogens, and of raloxifene on the glycosaminoglycan profile in the bladder and urethra of adult oophorectomized rats in comparison with noncastrated rats.

STUDY DESIGN

Sixty adult rats, of which 50 were submitted to bilateral oophorectomy, were studied. After 4 days, the latter were assigned to five groups of 10 animals each. For 30 consecutive days the following treatments were given: group 1, conjugated equine estrogens; group 2, conjugated equine estrogens combined with medroxyprogesterone acetate; group 3, medroxyprogesterone; group 4, raloxifene; and group 5, placebo. Thereafter the bladders and urethras of the animals were removed, processed to yield a dry powder of which the sulfated glycosaminoglycan content was determined by densitometry after agarose gel electrophoresis and that of hyaluronic acid by a fluorimetric assay.

RESULTS

Glycosaminoglycans found in the bladder and urethra were dermatan sulfate, heparan sulfate, and hyaluronic acid. In the bladder, hypoestrogenism or replacement with estrogens led to a lower sulfated glycosaminoglycan content. Replacement with estrogens and/or medroxyprogesterone reverted this effect. Hypoestrogenism decreased the dermatan sulfate/heparan sulfate ratio and reduced hyaluronic acid content. Estrogen therapy reverted this alteration and medroxyprogesterone addition annulled the estrogenic effect. In the urethra, castration did not alter hyaluronic acid content and sulfated glycosaminoglycan content, but raloxifene decreased the latter.

CONCLUSION

Castrated rats had a decrease in sulfated glycosaminoglycans and hyaluronic acid content in the bladder. Hormonal replacement altered the quantity and quality of glycosaminoglycans. In the urethra, raloxifene reduced sulfated glycosaminoglycans.

Interstitial cystitis: a review of current concepts of aetiology, diagnosis and therapy

Until recently, interstitial cystitis (IC) has been described as a chronic clinical syndrome of obscure aetiology and, consequently, specific treatment for the condition is lacking. IC has often been regarded as a diagnosis of exclusion in women complaining of chronic pelvic pains, frequency, dysuria, etc. and until recently most clinicians rarely considered this diagnosis in men. However, recent research efforts have begun to yield vital information on this underdiagnosed and distressing clinical condition regarding its aetiology and diagnosis and, consequently, more effective therapeutic options are now emerging. The aim of this review is to highlight these emerging concepts of the aetiology, diagnosis and innovative therapy of IC, in order to help clinicians confronted by patients with this disorder.

Hyaluronan is not elevated in urine or serum in Hutchinson-Gilford Progeria Syndrome

Elevations in urinary hyaluronan have been used as the principal laboratory indicator for diagnosis of Hutchinson-Gilford Progeria Syndrome (HGPS). Previous reports have provided evidence suggesting that children with HGPS have altered hyaluronan metabolism as indicated by a mean 17-fold increase in urinary hyaluronan over normal values. In addition, adults with Werner's syndrome have elevated urinary hyaluronan and even more prominent elevations in serum hyaluronan over age-matched controls. It is not known whether serum hyaluronan is elevated or whether serum hyaluronan levels correlate with urinary hyaluronan levels in children with HGPS. In a large cohort of 19 HGPS patients, we sought to confirm elevations in urinary hyaluronan concentration, to establish whether serum hyaluronan is elevated, to measure the size of urinary hyaluronan, and to determine whether serum or urine hyaluronidase levels are altered. We have analyzed urinary and serum hyaluronan levels in patients with HGPS and control patients (1) by using an enzyme-linked immunosorbent assay (ELISA)-like method in which sample hyaluronan in solution and hyaluronan in solid phase compete for a solution of biotinylated hyaluronan-binding protein, and (2) by fluorophore-assisted carbohydrate electrophoresis. The size of urinary hyaluronan was measured by using Sepharose CL-6B size exclusion chromatography. Serum and urinary hyaluronidases were evaluated quantitatively, by using ELISA, and qualitatively, by using a gel detection method. HGPS patients did not show a significant elevation in either urinary or serum hyaluronan. We detected no difference in the size of urinary hyaluronan between HGPS children and age-matched controls. Serum and urinary hyaluronidase levels were not significantly different in normal and HGPS patients. These studies indicate that neither serum nor urinary hyaluronan concentration is a reliable diagnostic or prognostic marker for HGPS and underscore a difference between adult and childhood progerias.

Current management of interstitial cystitis

The management of patients with IC remains a challenge because no single agent has proven universally effective. DMSO and PPS have been evaluated through early placebo-controlled trials, and these two agents are FDA approved treatments for IC. BCG is currently undergoing a large placebo-controlled trial, and hyaluronic acid is receiving similar clinical evaluation. Sacral nerve root stimulation shows promise with early favorable results. As with any treatment algorithm, it is reasonable to begin with conservative treatment using time-dependent milestones, allowing adequate trials of successive therapy while ensuring an appropriate pace for timely symptom resolution.

Urine markers of interstitial cystitis

This article describes the current state of the art with regard to urine markers of interstitial cystitis (IC), and describes the areas that need continuing research. Articles referenced in MEDLINE that describe urine alterations in IC were reviewed. Additional articles were identified by cross-referencing. The different marker alterations were tabulated. The relevant articles were discussed, considering different purposes for urine markers including: (1) diagnosing IC; (2) confirming a specific pathophysiology for IC; and (3) predicting or following response to a specific treatment. Currently, 2 markers (glycoprotein-51 and antiproliferative factor [APF]) clearly separate IC and control subjects, with minimal overlap. Markers that correlate with specific bladder biopsy features include 1,4-methylimidazole acetic acid and eosinophil cationic protein (ECP), which correlate with mast cell density, and interleukin (IL)-6, which correlates with mononuclear inflammation. Markers that changed after treatment were as follows: (1) nitric oxide synthase and cyclic guanosine monophosphate increased with oral L-arginine; (2) ECP decreased with subcutaneous heparin; (3) prostaglandin E(2) and kallikrein decreased after bladder distention; (4) neutrophil chemotactic activity decreased after dimethyl sulfoxide; (5) IL-2 inhibitor decreased after oral nifedipine; (6) IL-2, IL-6, and IL-8 decreased after bacille Calmette-Guérin (BCG) vaccine; and (7) APF and heparin-binding epidermal growth factor changed to or toward normal levels after bladder distention or sacral nerve stimulation. A larger number of urine alterations have been reported, and a few are being pursued further by correlating with bladder biopsy findings or treatment responses. Further research is needed.

Sensitivity and specificity of antiproliferative factor, heparin-binding epidermal growth factor-like growth factor, and epidermal growth factor as urine markers for interstitial cystitis

We previously determined that the urine of interstitial cystitis (IC) patients specifically contains a factor (antiproliferative factor [APF]) that inhibits primary bladder epithelial cell proliferation, and that it has significantly decreased levels of heparin-binding epidermal growth factor-like growth factor (HB-EGF) and increased levels of epidermal growth factor (EGF) compared with urine from asymptomatic controls and patients with bacterial cystitis. We sought to confirm the specificity of these findings for IC using a larger patient population, including control patients with a variety of urogenital disorders. Clean catch urine specimens were collected from 219 symptomatic IC patients, 113 asymptomatic controls without bladder disease, and 211 patients with various urogenital diseases including acute bacterial cystitis, vulvovaginitis, chronic nonbacterial prostatitis, overactive bladder, hematuria, stress incontinence, neurogenic bladder, benign prostatic hyperplasia, bladder or pelvic pain without voiding symptoms, bladder cancer, prostate cancer, or miscellaneous diagnoses including anatomic disorders. APF activity was determined by (3)H-thymidine incorporation into primary normal adult human bladder epithelial cells. HB-EGF and EGF levels were determined by enzyme-linked immunosorbent assay. APF activity was present significantly more often in IC than control urine specimens (P <0.005 for IC vs any control group; sensitivity = 94%, specificity = 95%, P <10(-82) for IC vs all controls). HB-EGF levels were also significantly lower and EGF levels significantly higher in IC urine than in specimens from controls (P <10(-84) and P <10(-36), respectively). These findings confirm the utility of APF, HB-EGF, and EGF as markers for IC. Understanding the reasons for altered levels of these markers may lead to understanding the pathogenesis of this disorder.

Pro-inflammatory activity of contaminating DNA in hyaluronic acid preparations

Hyaluronic acid (HA), an abundant non-sulfated glycosaminoglycan component of the extracellular matrix, has applications in drug delivery, tissue engineering and as an ingredient in cosmetics. HA preparations containing high-molecular-weight polymers are also used in the treatment of inflammatory disorders such as arthritis and interstitial cystitis. Low-molecular-weight fragments derived from HA have been reported to induce pro-inflammatory cytokines such as IL-12 and TNF-alpha, and could therefore potentially exacerbate existing inflammation. We therefore examined the pro-inflammatory activity of HA preparations, since inflammatory reactions are known to occur following administration of HA. We tested low-molecular-weight fragments obtained from seven different HA preparations, either by sonication (approximately equals 3 x 10(5) Da) or by hyaluronidase digestion (approximately equals 1 x 10(4) Da), for the ability to induce the synthesis of IL-12 and TNF-alpha by human monocytic cells. We found that two of the seven HA preparations tested stimulated the synthesis of IL-12 and TNF-alpha by human monocytic cells. We unexpectedly found that the induction of IL-12 and TNF-alpha by these HA preparations was not due to their degradation to low-molecular-weight fragments, since their native high-molecular-weight forms possessed the same ability to stimulate IL-12 and TNF-alpha synthesis, but was due to the presence of contaminating DNA. Treatment of these two HA preparations with deoxyribonuclease I abrogated or reduced the induction of IL-12 and TNF-alpha. It is clear from this study that HA preparations can induce the synthesis of pro-inflammatory cytokines by monocytes. The ability of HA to act as a pro-inflammatory mediator may not, however, be related to the presence of low-molecular-weight HA fragments, but to the presence of DNA. The presence of pro-inflammatory DNA in HA preparations should be evaluated before its use, not only for the treatment of patients with inflammatory disorders, but also before many other applications.

Chronic urologic pain syndromes

Chronic pains typically evaluated by a urologist are discussed from the perspective of a non-urologist pain clinician. The pathophysiology of some pains is understood and so we believe the patient's symptoms: examples are cancer-related pain and recurrent urolithiasis. We treat these pains with traditional analgesics. Other pains, such as those of interstitial cystitis, chronic prostatodynia, and chronic orchialgia are less understood and so are treated in a more conservative and often empiric fashion. Proposed therapies for these disorders are discussed.

Pathophysiology of interstitial cystitis

Despite being described over 80 years ago, interstitial cystitis remains a disease of undetermined aetiology and poor treatment outcomes. Generally agreed diagnostic criteria of this condition, which occurs primarily in females, are frequency, urgency and pain, a low-capacity hypersensitive bladder, and mucosal haemorrhages and tearing on bladder distention. Although current theories of pathophysiology are predominantly conjecture, important elements of the disease process are increased afferent and efferent neuronal activity, an excess of inflammatory mediators, increased epithelial permeability and possibly reduced bladder vascularity. Improved treatment outcome will follow a better understanding of pathophysiology.

Non-bacterial cystitis

The concept of non-bacterial cystitis (NBC) combines sterile urine and cystitic symptoms as well as inflammatory changes, in particular in the mucosa and submucosa of the bladder. It includes a multiplicity of vicious circles along the entire continence reflex. An understanding of NBC presupposes knowledge of the origin of the normal urinary urge and its successful control. Against the background of the steadily increasing incidence of interstitial cystitis (often irreversible end-stage NBC), it is suggested here that in the face of a failure of first-line therapeutics (anticholinergics, cyclic antidepressants or oestrogens), one must consider without delay the possible presence of NBC.

Characterization of the rabbit homolog of human MUC1 glycoprotein isolated from bladder by affinity chromatography on immobilized jacalin

The urinary bladder is lined by transitional epithelium, the glycocalyx on the luminal surface has interesting properties and is implicated in protective functions. Glycoconjugates are major components of the glycocalyx, but their biochemical nature is not well understood. Previous studies on rabbit bladder indicated the presence of significant levels of sialoglycoproteins compared to glycosaminoglycans in the epithelium. In this study, rabbit explant cultures were radiolabeled by precursor sugars or amino acids and a major lectin-reactive glycoprotein of rabbit bladder mucosa was isolated by affinity chromatography on jacalin-agarose. The radiolabeled glycoprotein was purified to homogeneity by a second cycle on the lectin column, followed by gel filtration and density gradient centrifugation. The average molecular mass of the glycoprotein was estimated to be 245 kDa and 210 kDa by gel filtration and SDS-PAGE, respectively. Its buoyant density was 1.40 g/ml, suggesting a carbohydrate content of approximately 50%. The percent distribution of glucosamine-derived tritium label in sialic acid, galactosamine, and glucosamine was 30, 52, and 18, respectively. The glycoprotein consisted entirely of small sialylated and neutral oligosaccharides O-glycosidically linked to serine and threonine residues. The same glycoprotein could be immunoprecipitated with an antibody against the carboxy terminal 17 amino acid peptide of human MUC1 mucin glycoprotein. This suggests that this mucin glycoprotein is the rabbit homolog of MUC1 glycoprotein, which has been previously established to be a component of human bladder urothelium and has been purified from human urine and biochemically characterized.

Interstitial cystitis

Interstitial cystitis is a complex inflammatory condition of the bladder. The pathophysiology of interstitial cystitis is incompletely understood, although altered epithelial permeability, mast cell activation and sensory afferent nerve upregulation play critical roles. A unified understanding of the pathogenesis of interstitial cystitis is emerging and this will hopefully lead to the introduction of novel therapies for pain and irritative voiding symptoms. Interstitial cystitis is a common disease among women and is frequently misdiagnosed as prostatitis and benign prostatic hyperplasia among men.