Effect of bilateral in vivo ischemia/reperfusion on the activities of superoxide dismutase and catalase: Response to a standardized grape suspension

Evaluation of the effects of omega-3 & interferon alpha-2b administration on partial bladder outlet obstruction in a rat model

BACKGROUND & OBJECTIVES

In bladder outlet obstruction-induced rat models, the transforming growth factor-beta (TGF-β) and collagen ratios have been shown to be increased. Increased TGF-β leads to fibrosis. In this study, the effect of omega-3 and interferon alpha-2b (IFN α-2b) was investigated on oxidative stress, inflammation and fibrosis in bladder structure in a partial bladder outlet obstruction (PBOO) rat model.

METHODS

A total of 35 male Wistar albino rats, weighing 300-350 g, were used in the study. The rats were randomly divided into five groups. At the end of the experimental period, bladders were harvested from all the rats, and pathological analysis of the rat bladder tissues was performed. In addition, investigations were carried out with enzymatic and non-enzymatic antioxidant systems to study the antioxidant properties of omega-3 fatty acid and IFN alpha-2b.

RESULTS

Increased bladder weight in the PBOO group, in comparison to the control group, was decreased by the administration of omega-3 and IFN α-2b (P=0.002). Significantly higher superoxide dismutase (SOD) levels were detected in group 2 in comparison to the control group. It was also detected that serum SOD, glutathione peroxidase and nitric oxide (NO) levels were significantly higher in group 2 when compared to the control group (P<0.05). In the pathologic evaluation, group 2 showed significantly increased inflammation and fibrosis compared to the control group. Omega-3 treatment significantly decreased inflammation. It was shown that IFN α-2b application partially decreased inflammation.

INTERPRETATION & CONCLUSIONS

The results of the present study showed that in addition to the standard primary approaches to prevent the damage to the upper urinary tract secondary to PBOO, omega-3 fatty acid and IFN α-2b could be beneficial as adjunct treatment in clinical practice. However, this needs to be further investigated with prospective, randomized clinical trials with larger sample sizes.

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).

Inhibitory effect of a genistein derivative on pigmentation of guinea pig skin

This study demonstrated the mechanisms of the inhibitory effects of GD against UVB-induced pigmentation in guinea pig skin.

Comparative biochemical responses and antioxidant activities of the rabbit urinary bladder to whole grapes versus resveratrol

The objective of this study is to compare the antioxidant activity of a whole-grape suspension with the antioxidant activity or pure resveratrol on the effect of hydrogen peroxide (H2O2) on malondialdehyde (MDA) generation, choline acetyltransferase (ChAT) activity, calcium ATPase activity, and sarcoendoplasmic reticular ATPase (SERCA) of the male rabbit urinary bladder. MDA was used as a model for the effect of H2O2 on lipid peroxidation. ChAT, SERCA, and calcium ATPase were evaluated based on their importance in urinary bladder physiology and pathology. Four male rabbit bladders were used. Each bladder was separated into muscle and mucosa, frozen under liquid nitrogen and stored at -80 °C for biochemical evaluation. The effect of H2O2 on the enzymes listed above was determined in the presence and absence of either resveratrol or a whole-grape suspension. (1) Resveratrol was significantly more effective than the grape suspension at protecting the bladder muscle and mucosa against peroxidation as quantitated by MDA formation. (2) The grape suspension was significantly more effective at protecting ChAT activity against oxidative stress of the muscle than resveratrol. (3) Neither the grape suspension nor resveratrol were particularly effective at protecting the bladder muscle or mucosa calcium ATPase or SERCA against oxidative stress. (4) ChAT was significantly more sensitive to oxidative stress than either calcium ATPase or SERCA. These data support the idea that the grape suspension protects the mitochondria and nerve terminals to a significantly greater degree than resveratrol which suggests that the activities of the grape suspension are due to the combination of active components found in the grape suspension and not just resveratrol alone.

A Comparison of Total Antioxidant Capacities of Concord, Purple, Red, and Green Grapes Using the CUPRAC Assay

Considering how popular grapes are in terms of their antioxidant benefits, we compared concord, purple, red, and green grapes for total antioxidant capacity (TAC) and carbohydrate concentration. All grapes were acquired from commercial sources and samples of each were separated into skinned and not skinned groups. Each whole grape and the skins were individually homogenized and then separated into pulp and supernatant fractions. Each fraction was analyzed for total TAC and carbohydrates. The concord grapes and purple grapes had significantly higher TAC in the homogenates than did the red or green grapes. The concord grapes and green grapes had significantly higher TAC in the pulp than in the cytosol whereas the red and purple grapes had approximately the same amount. The majority of the TAC of the purple and red grapes was in the skin whereas the concord and green grapes had approximately the same TAC in the skin and pulp. The concord and purple grapes had the highest TAC when compared to the red and green grapes, whereas the red and green grapes had approximately the same total TAC.

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.

Effect of severity and duration of bladder outlet obstruction on catalase and superoxide dismutase activity

OBJECTIVES

To study the effects of partial bladder outlet obstruction on the cell's anti-oxidant defense mechanisms, superoxide dismutase and catalase, in order to elucidate how the bladder responds to oxidative stress.

METHODS

Four groups of eight rabbits were subjected to partial bladder outlet obstruction for 4, 8 and 12 weeks. Eight sham rabbits were used as the control group. The bladders were removed under anesthesia, and the muscle and mucosa were separated, frozen and stored at -80°C for analysis. Superoxide dismutase and catalase assays were carried out on these tissues. The groups were also categorized by severity (mild, intermediate and severe) of decompensation, as well as duration.

RESULTS

When separated by duration, catalase activity of the mucosa was significantly higher in the control and the 12-weeks obstructed rabbits. This activity was lower than the control in the 4- and 8-weeks obstructed rabbits. When separated by severity, catalase activity of the mucosa was significantly higher and severely decompensated than the muscle in the controls. When separated by duration or severity, superoxide dismutase activity of the muscle was significantly lower than controls for all obstructed rabbits. The activities of both superoxide dismutase and catalase were significantly reduced in the severely decompensated bladder smooth muscle, but not in the 12-weeks obstructed bladder smooth muscle.

CONCLUSIONS

Partial bladder outlet obstruction has significant effects on the activity of both superoxide dismutase and catalase in the bladder, with variations that are dependent on the severity and duration of the obstruction.

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.

Calcium effects on superoxide dismutase and catalase of the rabbit urinary bladder muscle and mucosa

PURPOSE

Superoxide dismutase (SOD) and catalase are two important antioxidant mechanisms that work together to reduce free radical damage. Intracellular free calcium in smooth muscle can change rapidly and many enzymes can be affected. The sensitivity of SOD and catalase activity to calcium was determined in both rabbit bladder smooth muscle and mucosa.

MATERIALS AND METHODS

Calcium sensitivity was analyzed by determining SOD and catalase activity in muscle and mucosa at the following calcium concentrations: 0 (in the presence of 1 mM EGTA), 1 and 5 mM CaCl(2).

RESULTS

SOD: EGTA resulted in increased SOD activity of bladder smooth muscle, whereas both 1 and 5 mM calcium significantly decreased SOD activity. EGTA had no effect on SOD activity of the mucosa whereas 1 and 5 mM calcium decreased SOD activity of the muscle. Catalase: 1 mM calcium resulted in decreased catalase activity of the muscle and no change in the activity of the mucosa, whereas 5 mM calcium resulted in increased catalase activity of the mucosa but no change in the activity of the muscle.

DISCUSSION

Mucosa showed more SOD and catalase activity than the muscle. Both SOD and catalase showed differing sensitivities to EGTA and calcium.

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.

Antioxidant levels in the pig urinary bladder: distribution within the bladder wall and in the urothelium derived from different bladder regions

This study was designed to determine the antioxidant levels in the urinary bladder wall layers as well as urothelium derived from different bladder regions. Samples of the urothelium, lamina propria, muscularis, and serosa were prepared from the pig's urinary bladder body, while samples used for regional mapping of the urothelium were prepared from trigone, ventral and dorsal middle bladder body, and apex region. Activities of superoxide dismutase, glutathione peroxidase, glutathione reductase, and catalase were determined. Concentrations of ascorbic acid and glutathione were also measured. Antioxidant activities, i.e. concentrations of superoxide dismutase, glutathione peroxidase, glutathione reductase and glutathione, were shown to be highest in the urothelium and progressively lower towards the serosa. Regional mapping of the urothelium singled out apex as the region with the lowest antioxidant activities, i.e. concentrations of glutathione peroxidase, ascorbic acid, and glutathione. The fact that antioxidants are concentrated in the urothelium implies that urothelium functions as a barrier against reactive species. The urothelium derived from the apex is the region with the lowest antioxidant levels and is therefore probably the region most liable to development of oxidative damage.

Grapes and human health: a perspective

Grapes are a valuable source of numerous phytonutrients, including the intensively studied constituent, resveratrol. A question worth addressing is the potential of dietary grape consumption to positively modulate human health. Many studies have suggested cardiovascular benefits, and some work has indicated cancer chemopreventive activity. Data are particularly compelling in the area of skin cancer prevention. With financial support provided by the California Table Grape Commission, novel and exciting preliminary data are emerging from independent research suggesting beneficial activity against other less prevalent but devastating illnesses, such as Alzheimer's disease and urinary bladder dysfunction. It is further suggested that some of the copious amounts of data obtained with resveratrol may be relevant to grape consumption, especially responses that can be mediated by low concentrations of the substance. Whether future specific health claims will be sought from or allowed by regulatory authorities is not known, but based on existing data, it is clear that grapes should be considered an integral component of fruit and vegetable enriched diets that are recommended by health authorities and widely accepted as beneficial for human health and disease prevention.

The effect of ischemia/reperfusion on rabbit bladder--role of Rho-kinase and smooth muscle regulatory proteins

OBJECTIVES

To detect the effect of ischemia/reperfusion (I/R) injury on rabbit bladder, using physiological study and immunoblotting techniques.

METHODS

Twelve male New Zealand White rabbits were separated into three groups of 4 rabbits each. Group 1 served as control. Group 2 rabbits (ischemia-alone group) underwent in vitro bilateral ischemia surgery for 2 hours. In group 3 (I/R group), bilateral ischemia was similarly induced, and the rabbits were allowed to recover for 2 weeks. The contractile responses to electrical field stimulation, adenosine triphosphate, carbachol, and KCl were recorded. Expression levels of the signaling targets, Rho-kinase (ROK), protein kinase C potentiated inhibitor (CPI-17), caldesmon (CaD), and calponin (CaP) were analyzed by Western blotting.

RESULTS

Ischemia alone resulted in significant reductions in the contractile responses, whereas I/R resulted in further decreases after all forms of stimulation. In muscle layer, ROK expression increased immediately after ischemia and recovered to the control level after 2 weeks' recovery. However, in mucosa layer, ROK expression showed no significant change after ischemia but significantly increased after reperfusion. After ischemic damage, CPI-17, the functional protein involved in smooth-muscle Ca(2+) sensitization, was significantly increased and then decreased after 2 weeks of reperfusion. The expression of CaP significantly increased after ischemia and decreased after reperfusion. Levels of high-molecular-weight CaD significantly decreased after ischemia and remained very low after reperfusion.

CONCLUSIONS

This study provides further understanding of the role of regulatory proteins in detrusor muscle after ischemia and I/R-induced contractile dysfunction.

Mechanical bowel preparation with different solutions in rats with selective left colonic ischemia and reperfusion injury

BACKGROUND

The aim of this study was to evaluate the effects of preoperative mechanical bowel preparation (MBP) on colonic ischemia/reperfusion (I/R) injury.

METHODS

Seventy adult male Sprague-Dawley rats were divided randomly into 7 equal groups of 10 rats each. Groups were assigned as follows: group I = sham surgery; group II = I/R of left colon (control group); group III = intravenous heparin and metronidazole followed by I/R of the left colon; groups IV through VII = before I/R of the left colon, heparin and metronidazole and MBP were performed with sodium chloride (NaCl), Na phosphate, polyethylene glycol, and mannitol, respectively. Histopathologic and biochemical parameters were evaluated.

RESULTS

According to the histopathologic changes, the groups least affected by I/R injury were groups V and VII. Catalase activity was significantly higher in groups V and VII, and copper-zinc superoxide dismutase activity was significantly higher in group VII compared with the control group (P <.002).

CONCLUSIONS

MBP with sodium phosphate and mannitol appears to be more protective against I/R injury.