Coenzyme Q10 protect against ischemia/reperfusion induced biochemical and functional changes in rabbit urinary bladder

Therapeutic Effect of Platelet-Rich Plasma Improves Bladder Overactivity in the Pathogenesis of Ketamine-Induced Ulcerative Cystitis in a Rat Model

The present study attempted to elucidate whether intravesical instillation of platelet-rich plasma (PRP) could decrease bladder inflammation and ameliorate bladder hyperactivity in ketamine ulcerative cystitis (KIC) rat model. Female Sprague Dawley (S-D) rats were randomly divided into control group, ketamine-treated group, ketamine with PRP treated group, and ketamine with platelet-poor plasma (PPP) treated group. Cystometry and micturition frequency/volume studies were performed to investigate bladder function. The morphological change of bladder was investigated by Mason’s trichrome staining. Western blotting analysis were carried out to examine the protein expressions of inflammation, urothelial differentiation, proliferation, urothelial barrier function, angiogenesis and neurogenesis related proteins. The results revealed that treatment with ketamine significantly deteriorated bladder capacity, decreased voiding function and enhanced bladder overactivity. These pathological damage and interstitial fibrosis may via NF-κB/COX-2 signaling pathways and muscarinic receptor overexpression. PRP treatment decreased inflammatory fibrotic biosynthesis, attenuated oxidative stress, promoted urothelial cell regeneration, and enhanced angiogenesis and neurogenesis, thereafter recovered bladder dysfunction and ameliorate the bladder hyperactivity in KIC rat model. These findings suggested that the PRP therapy may offer new treatment options for those clinical KIC patients.

Bladder Hyperactivity Induced by Oxidative Stress and Bladder Ischemia: A Review of Treatment Strategies with Antioxidants

Overactive bladder (OAB) syndrome, including frequency, urgency, nocturia and urgency incontinence, has a significantly negative impact on the quality-of-life scale (QoL) and can cause sufferer withdrawal from social activities. The occurrence of OAB can result from an imbalance between the production of pro-oxidants, such as free radicals and reactive species, and their elimination through protective mechanisms of antioxidant-induced oxidative stress. Several animal models, such as bladder ischemia/reperfusion (I/R), partial bladder outlet obstruction (PBOO) and ovarian hormone deficiency (OHD), have suggested that cyclic I/R during the micturition cycle induces oxidative stress, leading to bladder denervation, bladder afferent pathway sensitization and overexpression of bladder-damaging molecules, and finally resulting in bladder hyperactivity. Based on the results of previous animal experiments, the present review specifically focuses on four issues: (1) oxidative stress and antioxidant defense system; (2) oxidative stress in OAB and biomarkers of OAB; (3) OAB animal model; (4) potential nature/plant antioxidant treatment strategies for urinary dysfunction with OAB. Moreover, we organized the relationships between urinary dysfunction and oxidative stress biomarkers in urine, blood and bladder tissue. Reviewed information also revealed the summary of research findings for the effects of various antioxidants for treatment strategies for OAB.

Autophagy Alters Bladder Angiogenesis and Improves Bladder Hyperactivity in the Pathogenesis of Ketamine-Induced Cystitis in a Rat Model

Simple Summary

Long-term ketamine abuse may increase urinary frequency, nocturia, urgency, bladder pain, dysuria, and sometimes hematuria. Evaluation of the pathophysiological mechanism of bladder voiding dysfunction in ketamine-induced cystitis (KIC) patients is a critical step for therapy. This study uses autophagy inducer (rapamycin, mTOR inhibitor) and inhibitor (wortmannin, PI3K-III inhibitor) to identify the role of autophagy in bladder angiogenesis alteration and bladder hyperactivity improvement.

Abstract

The present study attempts to elucidate whether autophagy alters bladder angiogenesis, decreases inflammatory response, and ameliorates bladder hyperactivity—thereby influencing bladder function in ketamine-induced cystitis (KIC). In our methodology, female Sprague-Dawley (S-D) rats were randomly divided into the control group, the ketamine group, the ketamine+rapamycin group, and the ketamine+wortmannin group. The bladder function, contractile activity of detrusor smooth muscle, distribution of autophagosome and autolysosome, total white blood cells (WBCs) and leukocyte differential counts, the expressions of autophagy-associated protein, angiogenesis markers, and signaling pathway molecules involved in KIC were tested, respectively. The data revealed that treatment with ketamine significantly results in bladder overactivity, enhanced interstitial fibrosis, impaired endothelium, induced eosinophil-mediated inflammation, swelling, and degraded mitochondria and organelles, inhibited angiogenesis, and elevated the phosphorylation of Akt. However, treatment with rapamycin caused an inhibitory effect on vascular formation, removed ketamine metabolites, decreased the eosinophil-mediated inflammation, and ameliorated bladder hyperactivity, leading to improve bladder function in KIC. Moreover, wortmannin treatment reduced basophil-mediated inflammatory response, improved bladder angiogenesis by increasing capillary density and VEGF expression, to reverse antiangiogenic effect to repair KIC. In conclusion, these findings suggested that autophagy could modulate inflammatory responses and angiogenesis, which improved bladder function in KIC.

The pretreatment of rats with nebivolol ameliorates bladder contractile dysfunction caused by ischemia-reperfusion injury

OBJECTIVE

The present study aimed to investigate the protective effect of nebivolol in the bladder isolated from rats exposed to ischemia-reperfusion (IR) injury.

METHODS

Sprague-Dawley rats were divided into control, IR, and nebivolol+IR groups. In the nebivolol+IR group, nebivolol was administered (0.4 mg/kg, subcutaneous) in rats prior to IR insult. At the end of the experimental protocol, the urinary bladder was rapidly isolated and bladder strips were mounted in an organ bath. After the equilibration period, potassium chloride (KCl, 20-100 mM) or carbachol (0.01-10 μM) was cumulatively added to the organ bath to generate cumulative concentration-response curves (CCRCs). Oxidative stress and interleukin 6 (IL-6) levels were also evaluated in the bladder tissue.

RESULTS

The CCRCs of KCl and carbachol were significantly reduced in the IR group compared to those of the control, and this inhibition was reversed by the pretreatment of rats with nebivolol (P < .05). The IR group's total antioxidant status was significantly lower with a concomitant increase in IL-6 levels than that of the control and nebivolol+IR groups (P < .05).

CONCLUSIONS

The present study indicates that pretreatment of rats with nebivolol (0.4 mg/kg) could improve bladder contractile dysfunction caused by IR injury through suppression of increased oxidative stress and IL-6 levels.

A Review of Oxidative Stress and Urinary Dysfunction Caused by Bladder Outlet Obstruction and Treatments Using Antioxidants

Urinary dysfunction is a common pathological condition that can significantly decrease the quality of life. Bladder outlet obstruction (BOO) is a major cause of urinary dysfunction, and various lower urinary tract diseases including benign prostatic hyperplasia and urethral stricture disease cause BOO. According to the results of a variety of animal experiments on partial BOO (PBOO), there is a general agreement that ischemic conditions and repeated ischemia/reperfusion of the bladder are closely associated with BOO-induced bladder damage, and that increased oxidative stress by ischemia/reperfusion plays a crucial role in the pathological mechanisms underlying urinary dysfunction. Changes in biomarkers of oxidative stress in PBOO animal models support this association between oxidative stress and urinary dysfunction. Oxidative stress is defined as an imbalance between the production of pro-oxidants, such as free radicals and reactive species, and their elimination through protective mechanisms of antioxidants. Therefore, organizing the knowledge on the state of oxidative stress, changes in biomarkers, and biological roles of antioxidants in systemic and bladder tissues is essential to understand the detailed pathological characteristics of the urinary dysfunction caused by PBOO. Furthermore, information on drugs and supplements that have antioxidant effects is important for defining treatment strategies for urinary dysfunction with PBOO. In this review, we paid special attention to the following three issues; (1) changes in oxidative stress, including its biomarkers, (2) antioxidant status, and (3) previous reports on treatment strategies involving agents with antioxidative activity for urinary dysfunction caused by BOO. In particular, we provide systematic information on the detailed mechanisms underlying the antioxidative effects of agents used to treat PBOO. In addition, we show present research issues and research limitations, as well as suggest possible future antioxidant treatment strategies for patients with PBOO.

Effects of Ganoderma Lucidum shell-broken spore on oxidative stress of the rabbit urinary bladder using an in vivo model of ischemia/reperfusion

Oxidative stress plays an important role in specific disease pathophysiology and the aging process. In the history of human kind, many herbs were utilized for disease prevention and anti-aging treatment. However, there are few direct evidences provided by modern laboratory technology. The current study was designed to evaluate Ganoderma Lucidum's (GL) ability to reduce the damage from in vivo ischemia/reperfusion (I/R) using a rabbit model of I/R that has been effectively utilized to prove the effects of drugs and supplements to reduce oxidative stress. Urinary bladder dysfunction secondary to benign prostatic hyperplasia (BPH) is a major affliction of aging men. One of the major etiologies of obstructive bladder dysfunction (OBD) is oxidative stress induced by I/R. Pharmaceutical studies and clinical research have proven that GL is useful in helping to prevent certain types of pathology and also helpful in prolonging human life in part by acting as an antioxidant. Using an in vivo model of I/R, we have investigated the ability of GL to protect bladder function from oxidative damage mediated by I/R. Our studies demonstrated that ischemia followed by reperfusion resulted in a significant decrease in bladder compliance and decreases in the contractile responses to a variety of forms of contractile stimulation. Pretreatment of rabbits with Ganoderma Lucidum prior to subjecting the rabbits to I/R completely inhibited the negative effects of I/R on both the compliance and contractile responses. These results demonstrate that Ganoderma provides excellent protection of bladder function following I/R (oxidative stress).

Doxorubicin inhibits muscle inflammation after eccentric exercise

BACKGROUND

Doxorubicin, a widely used anti-tumour drug, is known to cause muscle loss in cancer patients.

METHODS

Following an acute dose of doxorubicin injection (2.5 mg/kg per body weight), we examined macrophage distribution in rat soleus muscle challenged by eccentric exercise (downhill running). Long-term doxorubicin treatment (one injection every 3 days) on muscle mass and survival were also determined.

RESULTS

Under non-exercised condition, increased tumour necrosis factor (TNF)-alpha mRNA and decreased IL-10 mRNA were observed in soleus muscle of doxorubicin-treated rats, compared with saline-treated control rats. However, increases in inflammation score (leukocyte infiltration), nitrotyrosine level, and M1 macrophage (CD68⁺ ) invasion in exercised soleus muscle were absent in doxorubicin-treated rats, whereas increased M2 macrophage (CD163⁺ ) localization in exercised muscle was less affected by doxorubicin. Despites coenzyme Q (Q10) supplementation significantly elevated TNF-alpha mRNA, nitrotyrosine, and anti-oxidant gamma-glutamylcysteine synthetase (GCS) levels in non-exercised soleus muscle, these pro-inflammatory responses were also abolished in doxorubicin-treated rats. Results from long-term doxorubicin treatment show a significant muscle loss followed by an accelerated death, which cannot be reversed by Q10 supplementation.

CONCLUSIONS

(i) Doxorubicin impairs inflammation mechanism by depleting M1 macrophage in exercised skeletal muscle; (ii) Muscle loss and accelerated death during prolonged doxorubicin treatment cannot be reversed by Q10 supplementation.

Ketamine-induced ulcerative cystitis and bladder apoptosis involve oxidative stress mediated by mitochondria and the endoplasmic reticulum

Ketamine abusers develop severe lower urinary tract symptoms. The major aims of the present study were to elucidate ketamine-induced ulcerative cystitis and bladder apoptosis in association with oxidative stress mediated by mitochondria and the endoplasmic reticulum (ER). Sprague-Dawley rats were distributed into three different groups, which received normal saline or ketamine for a period of 14 or 28 days, respectively. Double-labeled immunofluorescence experiments were performed to investigate tight junction proteins for urothelial barrier functions. A TUNEL assay was performed to evaluate the distribution of apoptotic cells. Western blot analysis was carried out to examine the expressions of urothelial tight junction proteins, ER stress markers, and apoptosis-associated proteins. Antioxidant enzymes, including SOD and catalase, were investigated by real-time PCR and immunofluorescence experiments. Ketamine-treated rats were found to display bladder hyperactivity. This bladder dysfunction was accompanied by disruptions of epithelial cadherin- and tight junction-associated proteins as well as increases in the expressions of apoptosis-associated proteins, which displayed features of mitochondria-dependent apoptotic signals and ER stress markers. Meanwhile, expressions of mitochondria respiratory subunit enzymes were significantly increased in ketamine-treated bladders. Conversely, mRNA expressions of the antioxidant enzymes Mn-SOD (SOD2), Cu/Zn-SOD (SOD1), and catalase were decreased after 28 days of ketamine treatment. These results demonstrate that ketamine enhanced the generation of oxidative stress mediated by mitochondria- and ER-dependent pathways and consequently contributed to bladder apoptosis and urothelial lining defects. Such oxidative stress-enhanced bladder cell apoptosis and urothelial barrier defects are potential factors that may play a crucial role in bladder overactivity and ulceration.

Pharmacological treatment of chronic pelvic ischemia

Epidemiological studies have shown that lower urinary tract symptoms, including overactive bladder, commonly occur in both men and women, with an age-related increase in both sexes. Vascular endothelial dysfunction and urological symptoms are common in the metabolic syndrome; they also occur during the human ageing process and are independent risk factors for the development of atherosclerosis and hypertension. Pelvic arterial insufficiency may lead to impaired lower urinary tract perfusion and play an important role in the development of bladder dysfunction such as detrusor overactivity and overactive bladder. It seems reasonable, but has not been definitely established clinically, that chronic ischemia-related bladder dysfunction will progress to bladder underactivity. Studies in experimental models in rabbits and rats have shown that pelvic arterial insufficiency may result in significant bladder ischemia with reduced bladder wall oxygen tension, oxidative stress, increased muscarinic receptor activity, ultrastructural damage, and neurodegeneration. Several types of drug may be able to prevent some of these changes. Even if the α1-adrenoceptor blocker, silodosin, the phosphodiesterase type 5 inhibitor, tadalafil, the β3-α1-adrenoceptor agonist, mirabegron, and the free radical scavenger, melatonin, were unable to prevent the development of neointimal hyperplasia and consequent luminal occlusion in animal models, they all exerted a protecting effect on urodynamic parameters, and on the functional and morphological changes of the bladder demonstrable in vitro. The different mechanisms of action of the drugs suggest that many factors are involved in the pathogenesis of chronic ischemia-induced bladder dysfunction and can be targets for intervention. Since several of the agents tested are used clinically and effectively for relieving lower urinary tract symptoms, the results from animal models of chronic bladder ischemia seem to have translational value. Animal models may be of relevance for designing clinical studies to demonstrate if a certain drug may prevent progression of ischemia-related functional and morphological bladder changes.

Ubiquinol supplementation protects against renal ischemia and reperfusion injury in rats

Generation of toxic oxygen metabolites followed by oxidant- and inflammatory-mediated tissue injury plays a crucial role in the pathogenesis of ischemia and reperfusion (IR). Ubiquinol, the reduced form of coenzyme Q10, is recognized for its potent antioxidant and anti-inflammatory properties in biological membranes. The present study was established to examine the possible protective effect of ubiquinol against renal IR injury. Groups of male Wistar rats were assigned into sham, ubiquinol, IR (45-min bilateral renal ischemia followed by 24-h reperfusion), and ubiquinol+ IR (ubiquinol 300 mg/kg given orally for 7 consecutive days before IR induction). Renal morphology, function, oxidative stress, and inflammatory markers were evaluated at the end of reperfusion. IR caused renal dysfunction as shown by significant increases in blood urea nitrogen, plasma creatinine, and a decrease in creatinine clearance. Light and electron microscopic examinations exhibited severe tubular damages and abnormal mitochondrial structure. IR-induced renal injuries were associated with significant increases in malondialdehyde, nitric oxide, tumor necrosis factor-α, but decreases in antioxidant thiols and superoxide dismutase. Pretreatment with ubiquinol obviously attenuated all the changes caused by IR, whereas it had no considerable effect in the sham-operated rats. These findings indicate that supplementation of ubiquinol prior to IR incidence confers functional and morphological protection to the ischemic kidney by maintaining the redox balance and regulating the generation of inflammatory mediator. The outcomes suggest that ubiquinol may be a potential candidate to counteract organ dysfunction in conditions involving IR injury.

Protective effects of estrogen on ischemia/reperfusion-induced bladder dysfunction in female rabbits

OBJECTIVE

The present study investigated the effects of ovarian hormone depletion and estrogen administration on ischemia/reperfusion (I/R)-induced bladder damage in female rabbits.

METHODS

Female New Zealand white rabbits were divided into five groups. A sham surgical procedure was performed on rabbits in group 1. In group 2, both vesical arteries were clamped for 2 hours and then released (I/R surgical procedure). In group 3, 17β-estradiol (100 μg/kg/d) was injected intramuscularly before I/R surgical procedure. In group 4, ovariectomies were performed before I/R surgical procedure. Group 5 had ovariectomy, recovered for 2 weeks, and then received 17β-estradiol for 2 weeks. I/R surgical procedure was performed thereafter. Rabbits were killed 7 days after I/R surgical procedure. Masson's trichrome stain was used, and immunohistochemical experiments were performed to evaluate interstitial fibrosis and intramural nerve changes. Western immunoblots were examined to determine the expressions of markers for inflammation, fibrosis, and oxidative stress.

RESULTS

I/R surgical procedure decreased bladder contractile responses by 30% to 50%. Ovarian hormone depletion further reduced bladder contractile function by 45% to 55% compared with the I/R group members that retained their ovaries. Moreover, I/R surgical procedure significantly decreased intramural neurofilament staining by two thirds compared with the control group. Estrogen replacement after ovariectomy significantly increased the density of nerve terminals. In addition, the expression of transforming growth factor-β and fibronectin increased twofold and fivefold after I/R, respectively. Ovarian hormone depletion further increased the expression of these inflammatory and fibrosis markers. Ovariectomy significantly exacerbated oxidative damage, whereas estrogen replacement diminished oxidative stress to a level approaching that of the control group.

CONCLUSIONS

I/R surgical procedure increases oxidative damage, enhances interstitial fibrosis, and results in bladder denervation. Ovarian hormone deficiency exacerbates this I/R-induced bladder damage, whereas estrogen therapy after ovariectomy attenuates this injury. These results reveal estrogen's protective effects on bladders subjected to I/R injury and the potential benefits of estrogen therapy on I/R-induced bladder damage.

Effects of supraphysiological testosterone treatment and orchiectomy on ischemia/reperfusion-induced bladder dysfunction in male rabbits

INTRODUCTION

The roles of testosterone and orchiectomy on male bladder subjected to ischemic/reperfusion (I/R) injuries received little attention. To fill this gap, the present study intended to examine testosterone and orchiectomy effects on male rabbits subjected to I/R damages.

AIM

To elucidate the effects of testosterone and orchiectomy on contractile response, bladder morphology, interstitial fibrosis, and oxidative stress in male rabbit bladder subjected to I/R surgery.

METHODS

Male New Zealand rabbits were distributed into five groups as follows: Group 1 received sham surgical procedure. In group 2, I/R surgery was performed. In group 3, testosterone (100 μg/kg/day) was intramuscularly injected prior to I/R surgery. In group 4, orchiectomy was performed prior to I/R surgery. In group 5, orchiectomy was performed with subsequent testosterone administration, followed by I/R surgery. All the rabbits were euthanized 7 days after I/R. Comparative studies were analyzed to elucidate the effects of testosterone and orchiectomy on bladder dysfunction subjected to I/R injuries.

MAIN OUTCOME MEASURES

Bladder contractile function was evaluated. Masson's trichrome staining and immunohistochemical studies were performed to evaluate bladder morphology and intramural nerve terminals. Western blotting was examined to investigate the expressions of fibrosis and oxidative stress markers.

RESULTS

I/R surgery significantly decreased bladder contractility in response to various stimulations with and without testosterone treatment. I/R damages decreased bladder nerve density with and without testosterone. The expressions of fibrosis and oxidative stress-related proteins were increased by I/R injuries with or without testosterone treatment. Testosterone depletion significantly decreased the expressions of transforming growth factor-β and fibronectin expressions after I/R injury. Supraphysiological testosterone treatment after orchiectomy greatly increased the expressions of these fibrosis proteins; however, orchiectomy alone ameliorated I/R injuries.

CONCLUSIONS

Testosterone treatment or orchiectomy affected I/R-induced bladder damages in male rabbits. Orchiectomy decreased the level of fibrosis and oxidative stress markers and increased neurofilament densities. Supraphysiological exogenous testosterone administration after orchiectomy further exacerbated such detrimental effects of I/R.

Effects of coenzyme Q10 on bladder dysfunction induced by chronic bladder ischemia in a rat model

PURPOSE

We investigated the protective effects of coenzyme Q10 on bladder dysfunction in a rat model of atherosclerosis induced chronic bladder ischemia.

MATERIALS AND METHODS

A total of 24 male Sprague-Dawley® rats at age 16 weeks were divided into 4 groups of 6 each, including group 1--untreated, sham operated rats, group 2--coenzyme Q10 treated, sham operated rats, group 3--untreated rats with chronic bladder ischemia and group 4--coenzyme Q10 treated rats with chronic bladder ischemia. Groups 3 and 4 received an endothelial injury to the iliac arteries and were fed a 2% cholesterol diet for 8 weeks. Groups 2 and 4 were treated with coenzyme Q10 and the others were treated with vehicle for 4 weeks. Eight weeks postoperatively we performed continuous in vivo cystometry, an in vitro detrusor muscle strip study and a malondialdehyde assay. Histological examination of the bladder walls and iliac arteries was also done.

RESULTS

In vivo cystometry revealed that coenzyme Q10 administration after the induction of chronic bladder ischemia prolonged micturition frequency and the intercontraction interval, and increased bladder capacity compared to those in untreated rats with chronic bladder ischemia. In the detrusor muscle strip study coenzyme Q10 administration after the induction of chronic bladder ischemia increased contractile responses compared to those in untreated rats with chronic bladder ischemia. Rats with chronic bladder ischemia also showed higher malondialdehyde in bladder tissue and serum than the other groups. Chronic bladder ischemia induced submucosal fibrosis of the bladder walls and a degenerative change in the blood vessel tunical media, as shown on histological examination.

CONCLUSIONS

Our study suggests that coenzyme Q10 acts as an antioxidant to protect bladder function in this chronic bladder ischemia model.

Partial outlet obstruction in rabbits: duration versus severity

OBJECTIVES

Oxidative stress is a major etiology of obstructed bladder dysfunction. The major goal of the current study was to correlate the level of oxidative stress with both the severity and duration of obstruction.

METHODS

A total of 32 New Zealand White rabbits were divided into four equal groups. Groups 1-3 received partial bladder outlet obstructions by standard methods and survived for 4, 8 or 12 weeks. Group 4 received sham surgery at the end of each time period, isolated strips were taken for contractility studies and the balance of the bladder was frozen as muscle and mucosa for quantification of nitrotyrosine and carbonyl-oxidized proteins derivatized into dinitrophenyl. For each duration, the eight rabbits were divided into three severity groups: mild, intermediate or severe decompensation.

RESULTS

Contractile responses decreased in proportion to both severity and duration. The level of both oxidative products correlated to a much higher degree with the level of severity than the duration. There were significant decreases in the contractile responses in the mild decompensation group, whereas the level of derivatized into dinitrophenyl and nitrotyrosine of the muscle remained at control levels. This was not the case for the 4 weeks obstructed group.

CONCLUSIONS

These findings suggest that the etiology for the mechanism of contractile dysfunction is not an oxidative stress.

A prospective randomized double-blind trial of grape juice antioxidants in men with lower urinary tract symptoms

AIMS

Many patients take alternative medications for their lower urinary tract symptoms (LUTS) either in addition or as a substitute for traditional therapies, despite a lack of clinical data. Grapes products are hypothesized to improve bladder function due to their antioxidant and membrane-protective actions. There is increasing evidence that progression of obstructed bladder dysfunction is related to bladder ischemia, reperfusion injury and free radical damage. We prospectively studied a standardized grape product on urinary symptoms.

METHODS

Men >45 years with significant LUTS were randomized to 240 ml daily of either 100% Concord grape juice or placebo. Participants were followed with validated questionnaires for LUTS, erectile dysfunction, and quality of life in addition to PSA, uroflow, and serum and urinary antioxidant levels. The primary endpoint was change in LUTS in Male International Continence Symptom score. The secondary endpoint was correlation between the level of antioxidants and changes in symptom scores.

RESULTS

One hundred thirteen participations were randomized with 96 completing the 3-month follow-up. There was no difference in the primary endpoint between the groups. (ISCmale score improved by a mean of 1.6 points in both groups.) There was no statistical difference between groups by PSA or secondary questionnaires. A statistical significance was found between uroflow rates. Linear regression analysis gave no correlation between antioxidants (serum or urine) and changes in symptom scores or grape juice consumption.

CONCLUSIONS

Our study did not demonstrate any difference in LUTS in men taking a daily 240 ml 100% grape juice versus placebo after 3 months.

Effect of hydrogen peroxide on rabbit urinary bladder citrate synthase activity in the presence and absence of a grape suspension

PURPOSE

The etiology of obstructive bladder dysfunction includes free radical damage to mitochondria. Feeding rabbits a standardized grape suspension protects the ability of the bladder to contract and empty in part by preventing mitochondrial damage, thus maintaining smooth muscle and mucosal metabolism. The objective of the current study is to determine the direct effect of this grape suspension on the response of mitochondria to the oxidative effects of hydrogen peroxide.

MATERIALS AND METHODS

Six male rabbits were anesthetized with sodium pentobarbital and the bladders excised. Four full thickness strips were obtained for contractile studies and the balance separated into smooth muscle and mucosa compartments by blunt dissection. The effect of hydrogen peroxide on the contractile response to field stimulation was quantitated. Each tissue was homogenized and the effects of increasing concentrations of hydrogen peroxide in the presence and absence of grape suspension on citrate synthase activity was determined.

RESULTS

Citrate synthase activity was significantly higher in the mucosa than in the muscle. The grape suspension had no effect on control citrate synthase activity. However, the grape suspension provided significant protection of both smooth muscle and mucosal citrate synthase activity.

CONCLUSIONS

These studies support the conclusion that the grape suspension provides direct protection of mitochondrial function.