The Beneficial Effect of Resveratrol on Rat Bladder Contractility and Oxidant Damage following Ischemia/Reperfusion

Proliferative mechanism of benign prostatic hyperplasia by NLRP3 inflammasome through the complement pathway

OBJECTIVES

The expressions of complement component C5a and NLRP3 inflammasome and the antiproliferative effect of resveratrol in benign prostatic hyperplasia (BPH) model rat were analyzed to clarify the BPH proliferative mechanism.

METHODS

This study used the pathological stromal-dominant BPH model rat by urogenital sinus implantation (UGS). Expression of C5a, NLRP3, Caspase-1, IL-1β, and IL-18 using rat BPH tissues at 2, 3, and 8 weeks (n = 6, respectively) after UGS implantation were analyzed by qRT-PCR, western blotting analysis, and immunohistochemical (IHC) analysis. Serum IL-1β levels in BPH model and sham rats were measured by enzyme-linked immunosorbent assay. Furthermore, resveratrol, as the NLRP3 pathway inhibitor, was administered to BPH model rat to assess the antiproliferative effect on the BPH proliferative process. The proliferative effect on prostate was evaluated by Ki-67 protein expression.

RESULTS

The expression levels of C5a, NLRP3, Caspase-1, IL-1β, and IL-18 in qRT-PCR, western blotting, and IHC were significantly upregulated in BPH tissues compared to control prostate tissues and showed increases with time (all p < 0.05). Serum IL-1β levels in BPH model rats had significantly increased compared to sham rats. On IHC, deposition of C5a, NLRP3, Caspase-1, IL-1β, and IL-18 was abundant in stromal areas of BPH. The administration of resveratrol significantly decreased prostate weight and expressions of NLRP3, IL-1β, IL-18, and Ki-67 (all p < 0.05).

CONCLUSIONS

NLRP3 inflammasome activation by complement C5a produces IL-1β and IL-18 through Caspase-1 during the BPH proliferative process. NLRP3 inflammasome have the possibilities to be a therapeutic target for BPH proliferation by inhibiting the NLRP3 inflammasome pathway.

Resveratrol Attenuates Degeneration and Apoptosis of Cardiomyocytes Induced by Aortic Clamping

INTRODUCTION

Objective: To investigate the potential beneficial effects of resveratrol (RVT) against ischemia-reperfusion injury of myocardial tissue during surgical treatment of ruptured abdominal aortic aneurysm.

METHODS

Four groups were established - control, ischemia/reperfusion (I/R), sham (I/R+solvent/dimethyl sulfoxide [DMSO]), and I/R+RVT. Ruptured abdominal aortic aneurysm model was used as the experimental protocol.

RESULTS

In the I/R and I/R+DMSO groups, malondialdehyde (MDA) levels in myocardial tissue were found to be significantly increased compared to the control group. The MDA level in myocardial tissue was significantly decreased in the I/ R+RVT group compared to the I/R group. In I/R and I/R+DMSO groups, glutathione peroxidase (GSH) levels in myocardial tissue were found to be significantly decreased compared to the control group. The GSH level in the myocardial tissue was significantly increased in the I/R+RVT group compared to the I/R group. In the light microscope, isotropic and anisotropic band disorganized atypical cardiomyocytes in the I/R group and degenerative cardiomyocytes and edematous areas in the I/R+DMSO group were observed. Degenerative cardiomyocytes and edematous areas were decreased in the I/R+RVT group. When heart tissue sections incubated with cleaved caspase-3 primary antibodies were examined under the light microscope, apoptotic cardiomyocytes were present in I/R and I/R+DMSO groups. A decrease in the number of apoptotic cardiomyocytes was observed in the I/R+RVT group.

CONCLUSION

The findings of the present study indicate that RVT exhibits protective effects against ischemia-reperfusion injury occurring in the myocardium as a distant organ as a result of abdominal aorta clamping.

Spasmolytic and Uroprotective Effects of Apigenin by Downregulation of TGF-β and iNOS Pathways and Upregulation of Antioxidant Mechanisms: In Vitro and In Silico Analysis

Apigenin is a phytochemical obtained from Chamomilla recutita. Its role in interstitial cystitis is not yet known. The present study is aimed at understanding the uroprotective and spasmolytic effects of apigenin in cyclophosphamide-induced interstitial cystitis. The uroprotective role of apigenin was analyzed by qRT-PCR, macroscopic analysis, Evans blue dye leakage, histological evaluation, and molecular docking. The spasmolytic response was measured by adding cumulative concentrations of apigenin to isolated bladder tissue pre-contracted with KCl (80 mM) and carbachol (10^-9-10^-4) on non-incubated and pre-incubated tissues with atropine, 4DAMP, methoctramine, glibenclamide, barium chloride, nifedipine, indomethacin, and propranolol. Apigenin inhibited pro-inflammatory cytokines (IL-6, TNF-α and TGF 1-β) and oxidant enzymes (iNOS) while increasing antioxidant enzymes (SOD, CAT, and GSH) in CYP-treated groups compared to the control. Apigenin restored normal tissue of the bladder by decreasing pain, edema, and hemorrhage. Molecular docking further confirmed the antioxidant and anti-inflammatory properties of apigenin. Apigenin produced relaxation against carbachol-mediated contractions, probably via blockade of M₃ receptors, K_ATP channels, L-type calcium channels, and prostaglandin inhibition. While the blockade of M₂ receptors, K_IR channels, and β-adrenergic receptors did not contribute to an apigenin-induced spasmolytic effect, apigenin presented as a possible spasmolytic and uroprotective agent with anti-inflammatory, antioxidant effects by attenuating TGF-β/iNOS-related tissue damage and bladder muscle overactivity. Thus, it is a potential agent likely to be used in treatment of interstitial cystitis.

Resveratrol prevents acute renal injury in a model of ruptured abdominal aortic aneurysm

OBJECTIVE

To examine the biochemical and histopathological effects of ischemia/reperfusion (I/R) injury in a ruptured abdominal aortic aneurysm (RAAA) model in rats, and to investigate the potential protective role of resveratrol.

METHODS

Thirty-two male Sprague-Dawley rats were randomly assigned into four groups-control, I/R, sham (I/R + solvent/dimethyl sulfoxide), and I/R + resveratrol. The control group underwent midline laparotomy only. In the other groups, infrarenal vascular clamps were attached following 60-min shock to the abdominal aorta. Ischemia was applied for 60 min followed by reperfusion for 120 min. In the I/R + resveratrol group, intraperitoneal 10 mg/kg resveratrol was administered 15 min prior to ischemia and immediately before reperfusion. The I/R + dimethyl sulfoxide group received dimethyl sulfoxide, and the I/R group was given saline solution. All animals were sacrificed by exsanguination from the carotid artery at the end of the experiment. In addition to histopathological examination of the rat kidney tissues, malondialdehyde, glutathione, catalase, and nitric oxide levels were also investigated.

RESULTS

A decrease in glutathione, catalase and nitric oxide levels, together with increases in malondialdehyde levels, numbers of apoptotic renal tubular cells, caspase-3 levels, and tubular necrosis scores, were observed in the IR and I/R + dimethyl sulfoxide groups. In contrast, resveratrol increased glutathione, catalase and nitric oxide levels in renal tissues exposed to I/R, while reducing malondialdehyde levels, apoptotic renal tubular cell numbers, caspase-3 levels, and tubular necrosis scores.

CONCLUSION

Our findings suggest that resveratrol can be effective against I/R-related acute kidney damage developing during RAAA surgery by reducing oxidative stress and apoptosis.

Hyperbaric oxygen therapy prevents subarachnoid hemorrhage-induced apoptosis and impaired contractility of the rabbit bladder

AIM

To explore the effects of experimental subarachnoid hemorrhage (SAH) on rabbit urinary bladder and to assess the potential protective effects of hyperbaric oxygen therapy (HBOT).

METHODS

A total of 15 male New Zealand white rabbits were divided randomly to one of three groups: group I was spared as the control group (n = 5), group II was exposed to SAH, received no treatment, and acted as the SAH group (n = 5) and group III was exposed to SAH and received five sessions of HBOT (started 12 hours after SAH induction and was given twice daily for the first 2 days and once on the third day) and acted as the treatment group (n = 5). At 72 hours after the SAH induction, bladders from all animals were removed for in vitro organ bath experiments and biochemical analyses.

RESULTS

İsometric tension studies revealed that compared to group I, the contractile responses of the strips to carbachol in group II were significantly decreased whereas HBOT restored the contractile responses (P < .05). Caspase-3 and nitric oxide synthase (NOS) activities of bladder tissues were significantly increased in group II when compared with group I, whereas caspase-3 and NOS activities were significantly decreased in the tissues of group III (P < .01).

CONCLUSIONS

Subarachnoid hemorrhage stimulates apoptosis of the rabbit bladder and impairs the contractile response of the rabbit bladder to carbachol. HBOT creates a protective effect in rabbit bladder tissues and restores SAH-induced changes.

The effects of oxytocin on penile tissues in experimental priapism model in rats

PURPOSE

This study aimed to demonstrate the effects of oxytocin on penile tissues in ischemia-reperfusion injury developed after priapism.

METHODS

Forty Wistar Albino strain male rats were divided into four groups. The control group (n = 10) was not intervened. In Group 2, a rat model of priapism was constructed and maintained for 1 h. In Group 3, reperfusion was ensured for 30 min following priapism. Rats in Group 4 rats were given oxytocin 30 min before the induction of reperfusion following priapism. All rats were penectomized, and adequate amounts of blood sample were drawn. Inflammation, vasocongestion, desquamation, and edema in penile tissue were scored between 0 and 3 points (0: normal, 1: mild, 2: moderate, 3: severe) to evaluate the severity of tissue damage. The activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the levels of malondialdehyde (MDA), and nitric oxide (NO) in blood samples were determined spectrophotometrically.

RESULTS

In histopathological examination, statistically significant positive changes were detected in vasocongestion, inflammation, desquamation, and edema scores in Group 4 than in Group 2 and Group 3 (p < 0.001). Biochemical test results revealed that NO levels were significantly lower in Group 4 than in Group 3 (p < 0.001). Serum GSH-Px activities in Group 4 significantly increased when compared with the other groups 2 and 3 (p = 0.002, p = 0.001, respectively). There was no statistical difference among the groups regarding SOD activities and MDA levels (p > 0.05).

CONCLUSIONS

Oxytocin protected against priapism-induced ischemia-reperfusion injury developed in cavernosal tissue as observed based on histopathological and biochemical evidence. Although this is an experimental study, oxytocin can be thought as an alternative drug in the treatment of priapism.

Influence of the periprostatic adipose tissue in obesity-associated mouse urethral dysfunction and oxidative stress: Effect of resveratrol treatment

Obese mice display overactive bladder (OAB) associated with impaired urethra smooth muscle (USM) function. In this study, we evaluated the role of the adipose tissue surrounding the urethra and prostate in obese mice (here referred as periprostatic adipose tissue; PPAT) to the USM dysfunction. Male C57BL6/JUnib mice fed with either a standard-chow or high-fat diet to induce obesity were used. In PPAT, histological analysis, and qPCR analysis for gp91phox, tumor necrosis factor-α (TNF-α) and superoxide dismutase (SOD) were conducted. In USM, concentration-response curves to contractile and relaxing agents, as well as measurements of reactive-oxygen species and nitric oxide (NO) levels were performed. The higher PPAT area in obese mice was accompanied by augmented gp91phox (NOX2) and TNF-α expressions, together with decreased SOD1 expression. In USM of obese group, the contractile responses to phenylephrine and vasopressin were increased, whereas the relaxations induced with glyceryl trinitrate were reduced. The reactive-oxygen species and NO levels in USM of obese mice were increased and decreased, respectively. A higher SOD expression was also detected in obese group whilst no changes in the gp91phox levels were observed. We next evaluated the effects of the antioxidant resveratrol (100 mg/kg/day, two-weeks, PO) in the functional alterations and NO levels of obese mice. Resveratrol treatment in obese mice reversed both the functional USM dysfunction and the reduced NO production. Our data show that PPAT exerts a local inflammatory response and increases oxidative stress that lead to urethral dysfunction. Resveratrol could be an auxiliary option to prevent obesity-associated urethral dysfunction.

Antioxidant Agent Quercetin Prevents Impairment of Bladder Tissue Contractility and Apoptosis in a Rat Model of Ischemia/Reperfusion Injury

OBJECTIVES

To examine the possible protective effect of quercetin (QT), which is well known for its antioxidant and protective effects in circumstances of oxidative stress, on urinary bladder tissue in a rat model of ischemia/reperfusion (I/R) injury, which is a known factor for the development of lower urinary tract dysfunction partly mediated by the generation of free radicals causing oxidative damage.

METHODS

Thirty male Sprague-Dawley rats were subjected to I/R injury through clamping the abdominal aorta for 30 min and then allowing reperfusion for the next 60 min. Quercetin (20 mg/kg; subcutaneously) or vehicle were given before ischemia and just before reperfusion. Findings of the isometric contraction studies in the organ bath and of the histological examinations along with oxidative stress markers were evaluated in bladder tissues.

RESULTS

Increased malondialdehyde (MDA) levels and myeloperoxidase (MPO) activities and decreased glutathione (GSH) levels and superoxide dismutase (SOD) activities in the I/R group were reduced by QT treatment. In the I/R group, pro-apoptotic marker caspase-3 was increased and anti-apoptotic bcl-2 protein was decreased, while QT treatment significantly reversed these parameters. In the I/R group contractile responses of the bladder strips to carbachol were significantly lower than those of the control group, which were reversed by QT treatment.

CONCLUSION

Quercetin treatment protects bladder tissue contractility against acute I/R injury by decreasing oxidative stress and apoptosis induced by I/R.

Organ-Protective Effects of Red Wine Extract, Resveratrol, in Oxidative Stress-Mediated Reperfusion Injury

Resveratrol, a polyphenol extracted from red wine, possesses potential antioxidative and anti-inflammatory effects, including the reduction of free radicals and proinflammatory mediators overproduction, the alteration of the expression of adhesion molecules, and the inhibition of neutrophil function. A growing body of evidence indicates that resveratrol plays an important role in reducing organ damage following ischemia- and hemorrhage-induced reperfusion injury. Such protective phenomenon is reported to be implicated in decreasing the formation and reaction of reactive oxygen species and pro-nflammatory cytokines, as well as the mediation of a variety of intracellular signaling pathways, including the nitric oxide synthase, nicotinamide adenine dinucleotide phosphate oxidase, deacetylase sirtuin 1, mitogen-activated protein kinase, peroxisome proliferator-activated receptor-gamma coactivator 1 alpha, hemeoxygenase-1, and estrogen receptor-related pathways. Reperfusion injury is a complex pathophysiological process that involves multiple factors and pathways. The resveratrol is an effective reactive oxygen species scavenger that exhibits an antioxidative property. In this review, the organ-protective effects of resveratrol in oxidative stress-related reperfusion injury will be discussed.

Detrusor underactivity: Pathophysiological considerations, models and proposals for future research. ICI-RS 2013

AIMS

Detrusor underactivity, resulting in either prolonged or inefficient voiding, is a common clinical problem for which treatment options are currently limited. The aim of this report is to summarize current understanding of the clinical observation and its underlying pathophysiological entities.

METHODS

This report results from presentations and subsequent discussion at the International Consultation on Incontinence Research Society (ICI-RS) in Bristol, 2013.

RESULTS AND CONCLUSIONS

The recommendations made by the ICI-RS panel include: Development of study tools based on a system's pathophysiological approach, correlation of in vitro and in vivo data in experimental animals and humans, and development of more comprehensive translational animal models. In addition, there is a need for longitudinal patient data to define risk groups and for the development of screening tools. In the near-future these recommendations should lead to a better understanding of detrusor underactivity and its pathophysiological background. Neurourol. Urodynam. 33:591-596, 2014. © 2014 Wiley Periodicals, Inc.

Resveratrol prevents bradykinin-induced contraction of rat urinary bladders by decreasing prostaglandin production and calcium influx

Resveratrol, a polyphenol found in grapes and peanuts, exerts beneficial effects on a number of diseases of cardiovascular and central nervous system. However, effects of resveratrol on the urinary system have not been fully investigated. In the present study, we examined effects of resveratrol on bradykinin-induced contraction and release of prostaglandin E2 in isolated rat urinary bladders. The effects of resveratrol on contractions induced by several agonists (prostaglandin E2, prostaglandin F2α and carbachol) and high K+ were also examined. We found that resveratrol concentration-dependently reduced the bradykinin-induced contraction in the rat urinary bladder preparations. The higher concentration of resveratrol (100 μM) abolished the bradykinin-induced prostaglandin E2 release. Similar results were obtained when the cyclooxygenase inhibitor indomethacin (10 μM) was used instead of resveratrol. Resveratrol also attenuated the prostaglandin E2-, prostaglandin F2α-, and to a lesser extent carbachol-induced contractions. Contractile responses to bradykinin, prostaglandin E2 and carbachol were largely prevented by blockade of Ca2+ channels with diltiazem. Both resveratrol and diltiazem prevented contractions induced by an addition of Ca2+ (2.5- 10 mM) into Ca2+-free/50 mMK+ solution or by 50 mMK+ solution containing normal Ca2+ (2.5 mM). These results suggest that resveratrol prevents bradykinin-induced contractions by attenuating not only the production of prostaglandins but also actions of them. The effect of resveratrol on contractile actions seems to be in part due to inhibition of Ca2+ influx. Because bradykinin plays an important role in pathological conditions of urinary bladder function, resveratrol may exert beneficial effects on the urinary bladder diseases.

Protective and therapeutic effects of resveratrol on acetic acid-induced gastric ulcer

Sprague Dawley rats of both sexes were injected with either saline or RVT (10 mg/kg) either before or after acetic acid ulcer induction and decapitated 3, 5 or 10 days after ulcer. In the saline-treated ulcer groups, macroscopically evident ulcers were observed, while RVT-pretreated or RVT-treated groups had lower macroscopic ulcer scores. Likewise, the microscopic damage scores were lower for the RVT-administered groups. Gastric myeloperoxidase activity, malondialdehyde, collagen and tumour necrosis factor-alpha levels, as well as luminol- and lucigenin-enhanced chemiluminescence levels that were elevated in the saline-administered ulcer groups, were depressed with both RVT-pretreatment and RVT-treatment. Moreover, depleted glutathione levels in the ulcer groups were increased back to control levels by both pre- and post-treatments of RVT. Results demonstrate that resveratrol has both protective and therapeutic effects on oxidative gastric damage by suppressing pro-inflammatory cascades, including the activation of pro-inflammatory cytokines, accumulation of neutrophils and release of oxygen-derived free radicals.