Catechins prevents substance P-induced hyperactive bladder in rats via the downregulation of ICAM and ROS

The effect of SP/NK1R on expression and activity of glutaredoxin and thioredoxin proteins in prostate cancer cells

Substance P (SP), an important neuropeptide, has a crucial role in the progression of several cancers, including prostate cancer, through interacting with the neurokinin-1 receptor (NK1R). Oxidative stress is also involved in the onset and progression of prostate cancer. However, no studies have been performed on the cross-talk between the SP/NK1R system and cellular redox balance in prostate cancer, and how it is involved in tumorogenesis. We aimed to investigate the effect of the SP/NK1R system and the blockage of NK1R with its specific antagonist (aprepitant) on the cellular redox status of the prostate cancer cell line (PC3 and LNCaP). We performed the resazurin assay to evaluate the toxicity of the aprepitant on the PC3 and LNCaP cell lines. The intracellular reactive oxygen species (ROS) level was measured after SP and aprepitant treatment. The alterations of expression and activity of two crucial cellular oxidoreductases, glutaredoxin, and thioredoxin were evaluated by qRT-PCR and commercial kits (ZellBio GmbH), respectively. Our results revealed that SP increased ROS production and decreased the expression and activity of glutaredoxin and thioredoxin. On the other hand, treatment of cells with aprepitant showed reverse results. In conclusion, we found that the SP/NK1R system could promote prostate cancer progression by inducing oxidative stress. In addition, the inhibition of NK1R by aprepitant modulated the effect of the SP/NK1R system on the cellular redox system. Aprepitant might therefore be introduced as a candidate for the treatment of prostate cancer; however, more studies are required to confirm the validation of this hypothesis.

Vitamin D levels and the risk of overactive bladder: a systematic review and meta-analysis

CONTEXT

Overactive bladder is treated mainly with behavioral and drug therapy, and symptoms of urinary frequency and incontinence are challenging to eliminate. There is thus a continuous unmet need for new drugs with a substitution effect mechanism.

OBJECTIVE

It not known whether vitamin D deficiency can lead to overactive bladder or urinary incontinence or whether vitamin D supplementation alleviates bladder symptoms. This comprehensive systematic review with meta-analysis was conducted to determine whether overactive bladder is associated with vitamin D deficiency.

DATA SOURCES

The PubMed and Cochrane Library databases were searched systematically up to July 3, 2022.

DATA EXTRACTION

Initially, 706 articles were identified in the literature search, of which 13 were included in the systematic review: 4 randomized controlled trials, 3 cohort studies, 3 cross-sectional studies, and 3 case-control studies.

DATA ANALYSIS

An increased risk of overactive bladder and urinary incontinence was observed with vitamin D deficiency (odds ratio [OR] = 4.46; 95%CI, 1.03-19.33; P = 0.046 and OR = 1.30; 95%CI, 1.01-1.66; P = 0.036, respectively). Vitamin D levels were relatively low in patients with overactive bladder or urinary incontinence (SMD = -0.33; 95%CI, -0.61 to -0.06, P = 0.019). On the basis of existing data, the risk of urinary incontinence was reduced by 66% after vitamin D supplementation (OR = 0.34; 95%CI, 0.18-0.66; P = 0.001). Egger test was conducted to assess publication bias, and the results were tested for robustness using a sensitivity analysis.

CONCLUSIONS

Vitamin D deficiency increases the risk of overactive bladder and urinary incontinence, and vitamin D supplementation reduces the risk of urinary incontinence. The development of new strategies to prevent or alleviate bladder symptoms is crucial. Vitamin D supplementation may be gaining recognition as an effective strategy for prevention or alleviation of bladder symptoms such as overactive bladder and incontinence.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42022351443.

Molecular Pathophysiology and Potential Therapeutic Strategies of Ketamine-Related Cystitis

Ketamine was first synthesized as a clinical medicine for anesthesia in 1970. It has been used as a recreational drug because of its low cost and hallucination effect in the past decade. Part of ketamine abusers may experience ketamine-related cystitis (KC) and suffer from lower urinary tract symptoms, including urinary frequency, urgency, and severe bladder pain. As the disease progression, a contracted bladder, petechial hemorrhage of the bladder mucosa, and ureteral stricture with hydronephrosis may occur. The pathophysiology of KC is still uncertain, although several hypotheses have been raised. Cessation of ketamine abuse is critical for the management of KC to prevent progressive disease, and effective treatment has not been established. Research has provided some theoretical bases for developing in vitro experiments, animal models, and clinical trials. This review summarized evidence of molecular mechanisms of KC and potential treatment strategies for KC. Further basic and clinical studies will help us better understand the mechanism and develop an effective treatment for KC.

The redox modulatory effects of SP/NK1R system: Implications for oxidative stress-associated disorders

Oxidative stress which refers to redox imbalance with increased generation of reactive oxygen species (ROS) has been associated with the pathophysiology of diverse disease conditions. Recently, a close, yet not fully understood, relation between oxidative stress and neuropeptides, in particular, substance P (SP), has been reported in certain conditions. SP has been shown to affect the cellular redox environment through activation of neurokinin-1receptor (NK1R). It seems that SP/NK1R system and oxidative stress can act either synergistically or antagonistically in a context-dependent manner, thereby, influencing the pathology of various clinical disorders either destructively or protectively. Importantly, the interactions between oxidative stress and SP/NK1R system can be pharmacologically targeted. Therefore, a better understanding of the redox modulatory properties of SP/NK1R signaling will pave the way for identifying new therapeutic possibilities for attenuating oxidative stress-mediated damage. Towards this end, we performed a comprehensive search through PubMed/Medline and Scopus databases and discussed all related existing literature regarding the interplay between oxidative stress and SP/NK1R system as well as their implication in various clinical disorders, to provide a clear view and hence better management of oxidative damage.

Green Tea Polyphenol Catechins Inhibit Coronavirus Replication and Potentiate the Adaptive Immunity and Autophagy-Dependent Protective Mechanism to Improve Acute Lung Injury in Mice

Effective antiviral therapeutics are urgently required to fight severe acute respiratory syndrome (SARS) caused by a SARS coronavirus (SARS-CoV). Because polyphenol catechins could confer antioxidative, anti-inflammatory, antiviral, and antimicrobial activities, we assessed the therapeutic effects of catechins against SARS-CoV replication in Vero E6 cells, the preventive effect of catechins on CD25/CD69/CD94/CD8⁺ cytotoxic T lymphocytes-mediated adaptive immunity, and the protective effect on lipopolysaccharide-induced acute lung injury (ALI) in mice. We found that catechins containing 32.8% epigallocatechin gallate, 15.2% epicatechin gallate, 13.2 epicatechin, 10.8% epigallocatechin, 10.4% gallocatechin, and 4.4% catechin directly inhibited SARS-CoV replication at sub-micromolecular concentrations. Four-week catechins ingestion increased CD8⁺ T cell percentage, upregulated CD69⁺/CD25⁺/CD94-NKG2A/CD8⁺ T lymphocytes-mediated adaptive immunity, and increased type I cytokines release responding to ovalbumin/alum. Catechins significantly reduced lipopolysaccharide-induced cytokine storm and oxidative stress and ALI by inhibiting PI3K/AKT/mTOR signaling to upregulate Beclin-1/Atg5-Atg12/LC3-II-mediated autophagy mechanism. Pretreatment of autophagy inhibitor 3-Methyladenine reversed the inhibiting effects of catechins on the cytokines and oxidative stress levels and ALI. In conclusion, our data indicated that catechins directly inhibited SARS-CoV replication, potentiated the CD25/CD69/CD94/CD8⁺ T lymphocytes-mediated adaptive immunity and attenuated lipopolysaccharide-induced ALI and cytokine storm by PI3K/AKT/mTOR-signaling-mediated autophagy, which may be applied to prevent and/or treat SARS-CoV infection.

Are Nutraceuticals Beneficial in Chronic Kidney Disease?

Chronic kidney disease (CKD) is a worldwide health problem in which prevalence is constantly rising. The pathophysiology of CKD is complicated and has not been fully resolved. However, elevated oxidative stress is considered to play a vital role in the development of this disease. CKD is also thought to be an inflammatory disorder in which uremic toxins participate in the development of the inflammatory milieu. A healthy, balanced diet supports the maintenance of a good health status as it helps to reduce the risk of the development of chronic diseases, including chronic kidney disease, diabetes mellitus, and hypertension. Numerous studies have demonstrated that functional molecules and nutrients, including fatty acids and fiber as well as nutraceuticals such as curcumin, steviol glycosides, and resveratrol not only exert beneficial effects on pro-inflammatory and anti-inflammatory pathways but also on gut mucosa. Nutraceuticals have attracted great interest recently due to their potential favorable physiological effects on the human body and their safety. This review presents some nutraceuticals in which consumption could exert a beneficial impact on the development and progression of renal disease as well cardiovascular disease.

Vitamin D and thiol-disulfide homeostasis levels in postmenopausal women with overactive bladder syndrome

Background

This study aimed to find a relationship between vitamin D concentration and thiol-disulfide homeostasis in the pathophysiology of overactive bladder (OAB) syndrome in postmenopausal women.

Methods

A total of 76 postmenopausal women, referred for routine controls, were recruited between January and March 2018 to participate in this study. Participants with an overactive bladder questionnaire (OAB-q) score of >11 (n = 34) were included in the OAB syndrome group, while those with a score of <5 (n = 42) were included in the control group. Serum total antioxidant capacity, ischemia-modified albumin, C-reactive protein, 25-hydroxy vitamin D levels, and thiol-disulfide homeostasis were measured.

Results

Patients with OAB syndrome had waist circumferences of 106 ± 11 cm, and their body mass indexes (BMIs) were 30.8 ± 4.8 kg/m2. The control groups' waist circumferences were 102 ± 11 cm and their BMIs were 28.9 ± 4.3 kg/m2 (p = 0.069 and p = 0.098, respectively). The level of vitamin D in the control group was 33.7 (IQR: 30.7) nmol/L and 27.0 (IQR: 27.5) nmol/L (p = 0.081) in the OAB syndrome group.

Conclusions

We were not able to demonstrate with certainty any significant relationships between serum 25-hydroxy vitamin D levels and thiol-disulfide homeostasis parameters and OAB syndrome.

Nutrients, Nutraceuticals, and Xenobiotics Affecting Renal Health

Chronic kidney disease (CKD) affects 8–16% of the population worldwide. In developed countries, the most important risk factors for CKD are diabetes, hypertension, and obesity, calling into question the importance of educating and acting on lifestyles and nutrition. A balanced diet and supplementation can indeed support the maintenance of a general health status, including preservation of renal function, and can help to manage and curb the main risk factors for renal damage. While the concept of protein and salt restriction in nephrology is historically acknowledged, the role of some nutrients in renal health and the importance of nutrition as a preventative measure for renal care are less known. In this narrative review, we provide an overview of the demonstrated and potential actions of some selected nutrients, nutraceuticals, and xenobiotics on renal health and function. The direct and indirect effects of fiber, protein, fatty acids, curcumin, steviol glycosides, green tea, coffee, nitrates, nitrites, and alcohol on kidney health are reviewed here. In view of functional and personalized nutrition, understanding the renal and systemic effects of dietary components is essential since many chronic conditions, including CKD, are related to systemic dysfunctions such as chronic low-grade inflammation.

The Ameliorating Effect of Exogenous Melatonin on Urinary Bladder Function in Hyperosmolar Bladder Overactivity and its Influence on the Autonomic Nervous System Activity

This study was designed to investigate the effects of melatonin on the bladder hyperactivity in hyperosmolar-induced overactive bladder (OAB) rats. Additionally, the influence of melatonin on the autonomic nervous system (ANS) using heart rate variability (HRV) analysis was assessed. 40 rats were divided into four groups: I – control (n=12), II – rats with hyperosmolar OAB (n=6), III – rats with melatonin pretreatment and hyperosmolar OAB (n=6) and IV – control with melatonin pretreatment (n=6). In group III and IV melatonin in dose of 100 mg/kg was given. HRV measurements in 10 rats, as follow: control (n=2), control after melatonin treatment (n=2), rats with hyperosmolar OAB without (n=3), and after (n=3) melatonin treatment were conducted. This study demonstrates marked influence of melatonin on urinary bladder activity in hyperosmolar-induced OAB rats. These rats showed significantly reduced the detrusor motor overactivity resulting in the improvement of cystometric parameters after melatonin treatment when compared to the control, as follow: a significant increase of intercontraction interval (70 %) and functional bladder capacity (67 %), as well as a decrease of the basal pressure, detrusor overactivity index and motility index of 96 %, 439 % and 40 %, respectively. ANS activity analysis revealed sympathetic overactivity in OAB rats, and parasympathetic superiority in melatonin treated OAB rats. Melatonin treatment in rats with hyperosmolar OAB (group III) caused significant increase of nuHF parameter (from 51.00 ± 25.29 to 76.97 ± 17.43), as well as a decrease of nuLF parameter (from 49.01 ± 25.26 to 23.03 ± 17.43) and LF/HF ratio (from 1.280 ± 0.980 to 0.350 ± 0.330). In conclusion, melatonin suppresses hyperosmolar OAB, and modulates ANS activity by inhibition of the sympathetic drive. Therefore, melatonin may become a useful agent for OAB management.

l-Theanine inhibits proinflammatory PKC/ERK/ICAM-1/IL-33 signaling, apoptosis, and autophagy formation in substance P-induced hyperactive bladder in rats

AIMS

Upregulation of substance P (SP) and neurokinin-1 receptor (NK1R) activation induces pro-inflammatory bladder hyperactivity through the PKC/ERK/NF-κB/ICAM-1/IL-33 signaling pathways to increase the leukocyte infiltration and adhesion leading to reactive oxygen species (ROS) production, autophagy, and apoptosis. l-Theanine is a unique non-protein-forming amino acid present in tea (Camellia sinensis [L.] O. Kuntze) with its antioxidant, anti-inflammatory, and relaxation effects to improve cognition, mood, gastric ulcer injury, and cerebral ischemia/reperfusion injury, and posttraumatic stress disorder. We explored the protective effect of l-theanine on SP-induced bladder hyperactivity.

METHODS

In urethane-anesthetized female Wistar rats, we explored the transcystometrogram, pelvic nerve activity, proinflammatory PKC/ERK/NF-κB/ICAM-1/IL-33 signaling, apoptosis-related Caspase 3/poly-(ADP-ribose)-polymerase (PARP), and autophagy-mediated LC3 II expression by Western blot, electrophoretic-mobility shift assay and immunohistochemistry, bladder ROS amount by a ultrasensitive chemiluminescence method, and possible ROS sources from the different leukocytes by specific stains in SP-evoked hyperactive bladder.

RESULTS

l-Theanine dose-dependently depressed H₂ O₂ and HOCl activity in vitro. In urethane-anesthetized female Wistar rats, intra-arterial SP through NK1R activation increased voiding frequency (shortened intercontraction intervals) associated with the increase in bladder nerve activity, proinflammatory PKC/ERK/NF-κB/ICAM-1/IL-33 signaling, Caspase 3/PARP-mediated apoptosis, LC3 II-mediated autophagy, ROS amount, neutrophils adhesion, CD68 (monocyte/macrophage) infiltration, and mast cells degranulation in the hyperactive bladder. Intragastrical l-theanine (15 mg/kg) twice daily for 2 weeks efficiently ameliorated all the enhanced parameters in the SP-treated hyperactive bladder.

CONCLUSIONS

In conclusion, l-theanine through antioxidant and anti-inflammatory actions ameliorates SP-induced bladder hyperactivity via the inhibition of proinflammatory PKC/ERK/NF-κB/ICAM-1/IL-33 signaling, oxidative stress, bladder nerve hyperactivity, apoptosis, and autophagy. Neurourol. Urodynam. 36:297-307, 2017. © 2016 Wiley Periodicals, Inc.

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.

Therapeutic potential of traditional chinese medicine on inflammatory diseases

Increased oxidative stress induces inflammation to several tissues/organs leading to cell death and long-term injury. Traditional Chinese Medicine (TCM) with antioxidant, anti-inflammatory, anti-apoptotic, and autophagic regulatory functions has been widely used as preventive or therapeutic strategy in modern medicine. Oxidative stress and inflammation have been widely reported to contribute to cigarette smoke-induced lung inflammation, hepatotoxicity, or sympathetic activation-induced liver inflammation, lipopolysaccharide-induced renal inflammation, and substance P-mediated neurogenic hyperactive bladder based on clinical findings. In this review, we introduce several evidences for TCM treatment including Monascus adlay (MA) produced by inoculating adlay (Cois lachrymal-jobi L. var. ma-yuen Stapf) with Monascus purpureus on lung injury, Amla (Emblica officinalis Gaertn. of Euphorbiaceae family) on hepatotoxin-induced liver inflammation, Virgate Wormwood Decoction (Yīn Chén Hāo tāng) and its active component genipin on sympathetic activation–induced liver inflammation, and green tea extract and its active components, catechins, or a modified TCM formula Five Stranguries Powder (Wǔ Lén Sǎn) plus Crataegi Fructus (Shān Zhā) on hyperactive bladder. The pathophysiologic and molecular mechanisms of TCM on ameliorating inflammatory diseases are discussed in the review.

Anti-oxidant activity and attenuation of bladder hyperactivity by the flavonoid compound kaempferol

OBJECTIVES

To evaluate the anti-oxidant activity of the flavonoid compound, kaempferol, and to examine its role in the suppression of oxidative stress and attenuation of bladder hyperactivity in a rat model of bladder injury.

METHODS

The anti-oxidative activity of kaempferol was examined in lipopolysaccharide-treated RAW264.7 macrophages by using flow cytometry. For in vivo studies, rats were pretreated with kaempferol or vehicle for 24 h. The rat urothelium was injured by the administration of protamine sulfate for 1.5 h and irritated by the subsequent infusion of potassium chloride for 4 h. Oxidative stress in the bladder tissue was assessed using chemiluminescence assay, and the bladder pressure was determination by cystomertrogram.

RESULTS

Kaempferol significantly suppressed lipopolysaccharide-induced reactive oxygen species production in RAW264.7 rat macrophages. Exposure of the rat bladder to sequential infusion of protamine sulfate and potassium chloride induced bladder hyperactivity. Pretreatment with kaempferol, prevented the formation of reactive oxygen species and prolonged the intercontraction interval.

CONCLUSION

Kaempferol suppresses oxidative stress and attenuates bladder hyperactivity caused by potassium chloride after protamine sulfate-induced bladder injury.

Novel mouse model of chronic inflammatory and overactive bladder by a single intravesical injection of hydrogen peroxide

There is so far no generally accepted animal model of chronic cystitis by which potential therapies can be evaluated. In this study, we aimed to establish a new mouse model of cystitis based on the proinflammatory effects of reactive oxygen species. A single intravesical injection of 1.5% hydrogen peroxide (H2O2) significantly increased the numbers of voids by 1 day after injection in female mice, which lasted up to 7 days. The H2O2 injection rapidly increased the bladder weight by 3 h in parallel with the histological damage and hyperpermeability of urothelial barrier. Although the urothelial dysfunction was recovered to normal by 7 days, increase in bladder weight, edematous thickening of the submucosa, and vascular hyperpermeability were apparent even 7 days after injection. During the time course, massive infiltration of neutrophils and increased expression of inflammatory cytokines were observed in the bladder. An intraperitoneal administration of oxybutynin, amitriptyline, indomethacin, or morphine attenuated the H2O2-induced frequent urination. These findings suggest that an intravesical injection of H2O2 induces relatively long-lasting inflammatory and overactive bladder, compared with existing cystitis models. The intravesical H2O2 injection model may be a simple and useful tool in the pathological study and drug discovery for chronic cystitis.

Role of substance P in renal injury during DOCA-salt hypertension

Substance P (SP), a neurokinin-1 receptor (NK-1R) agonist, is mainly produced and stored in primary sensory nerves and, upon its release, participates in cardiovascular and renal functional regulation. This study tests the hypothesis that activation of the NK-1Rs by SP occurs during hypertension induced by deoxycorticosterone (DOCA)-salt treatment, which contributes to renal injury in this model. C57BL/6 mice were subjected to uninephrectomy and DOCA-salt treatment in the presence or absence of administration of selective NK-1 antagonists, L-733,060 (20 mg/kg·d, ip) or RP-67580 (8 mg/kg·d, ip). Five weeks after the treatment, mean arterial pressure determined by the telemetry system increased in DOCA-salt mice but without difference between NK-1R antagonist-treated or NK-1R antagonist-untreated DOCA-salt groups. Plasma SP levels were increased in DOCA-salt compared with control mice (P < 0.05). Renal hypertrophy and increased urinary 8-isoprostane and albumin excretion were observed in DOCA-salt compared with control mice (P < 0.05). Periodic acid-Schiff and Masson's trichrome staining showed more severe glomerulosclerosis and tubulointerstitial injury in the renal cortex in DOCA-salt compared with control mice, respectively (P < 0.05). Hydroxyproline assay and F4/80-staining showed that renal collagen levels and interstitial monocyte/macrophage infiltration were greater in DOCA-salt compared with control mice, respectively (P < 0.05). Blockade of the NK-1R with L-733,060 or RP-67580 in DOCA-salt mice suppressed increments in urinary 8-isoprostane and albumin excretion, interstitial monocyte/macrophage infiltration, and glomerulosclerosis and tubulointerstitial injury and fibrosis (P < 0.05). Thus, our data show that blockade of the NK-1Rs alleviates renal functional and tissue injury in the absence of alteration in blood pressure in DOCA-salt-hypertensive mice. The results suggest that elevated SP levels during DOCA-salt hypertension play a significant role contributing to renal damage possibly via enhancing oxidative stress and macrophage infiltration of the kidney.

Green tea catechins decrease oxidative stress in surgical menopause-induced overactive bladder in a rat model

What's known on the subject? and What does the study add? Ovary hormone deficiency and the age-related changes in post-menopausal women are subjected to a number of urological dysfunctions, including overactive bladder syndrome. Green tea is a popular healthy drink worldwide and its extract catechin has strong anti-inflammatory and antioxidant properties. EGCG, the major type of catechin, is an antioxidant polyphenol flavonoid isolated from green tea. EGCG supplement could prevent ovariectomy-induced bladder dysfunction in a dose-related manner through its anti-oxidant, anti-fibrosis and anti-apoptosis effects.

OBJECTIVE

To evaluate whether green tea extract, epigallocatechin gallate (EGCG), could prevent ovariectomy-induced overactive bladder (OAB) and to investigate its antioxidant, anti-apoptotic and anti-fibrosis effects.

MATERIALS AND METHODS

In all, 48 female Sprague-Dawley rats were divided into four groups. After bilateral ovariectomy, the first group served as the ovariectomy control, the second group received EGCG 1 µM/kg daily i.p. injection after ovariectomy surgery, and the third group received EGCG 10 µM/kg daily i.p. injection. The fourth group was taken as the sham without ovariectomy surgery. The rats were killed after 6 months after ovariectomy surgery. Cystometrograms were performed for the measure of bladder overactivity. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling (TUNEL) assay was used to evaluate apoptotic cells. Western immunoblots were performed to determine the expressions of inflammatory markers, apoptosis-associated proteins and oxidative stress markers.

RESULTS

Long-term ovariectomy significantly increased non-voiding contractions and decreased bladder compliance. Treatment with EGCG significantly increased bladder compliance and diminished non-voiding contractions. Ovariectomy significantly increased apoptotic cells and enhanced interstitial fibrosis in bladders. The expression of caspase-3 significantly increased, while that of Bcl-2 notably decreased after ovariectomy. Inflammatory and fibrosis markers, TGF-β, fibronectin and type I collagen expressions were significantly increased after 6 months of ovariectomy surgery. Treatment with EGCG significantly decreased TGF-β and type I collagen expressions. Oxidative stress markers, nitrotyrosine and protein carbonylation levels were significantly increased in the ovariectomy group. EGCG could attenuate this oxidative damage in dose-dependent fashion.

CONCLUSIONS

Ovariectomy increased oxidative damage, enhanced voiding frequency and decreased bladder compliance. EGCG could restore ovariectomy-induced bladder dysfunction in a dose-dependent fashion through antioxidant, anti-fibrosis and anti-apoptosis effects.

Green tea extract supplementation ameliorates CCl4-induced hepatic oxidative stress, fibrosis, and acute-phase protein expression in rat

BACKGROUND/PURPOSE

We evaluated the long-term effects of green tea extract (GTE) supplementation on oxidative stress, biliary acute phase protein expression, and liver function in CCl(4)-induced chronic liver injury.

METHODS

We evaluated the antioxidant activity of GTE in comparison with those of vitamin C, vitamin E, and β-carotene in vitro by using an ultrasensitive chemiluminescence analyzer. Chronic liver injury was induced by intraperitoneally administering carbon tetrachloride (CCl(4)) (1 mL/kg body weight, twice weekly) to female Wistar rats for 8 weeks. The effects of low (4 mg/kg body weight per day) and high (20 mg/kg body weight per day) doses of intragastric GTE on CCl(4)-induced liver dysfunction and fibrosis were examined by measuring the bile and blood reactive oxygen species levels and biochemical parameters by using Western blot and two-dimensional polyacrylamide gel electrophoresis techniques.

RESULTS

GTE has greater scavenging activity against O(2)(-), H(2)O(2), and Hypochlorous acid (HOCl) in vitro than vitamin C, vitamin E, and β-carotene do. In vivo, CCl(4) markedly increased bile and blood reactive oxygen species production, lipid accumulation, number of infiltrated leukocytes, fibrosis, hepatic hydroxyproline content, and plasma alanine aminotransferase and aspartate aminotransferase activities, and reduced plasma albumin levels. Two-dimensional polyacrylamide gel electrophoresis revealed that CCl(4) increased the acute-phase expression of six biliary proteins and decreased hepatic B-cell lymphoma 2 (Bcl-2), catalase, and CuZn superoxide dismutase protein expression. GTE supplementation attenuated CCl(4)-enhanced oxidative stress, levels of biochemical parameters, pathology, and acute-phase protein secretion, and preserved antioxidant/antiapoptotic protein expression.

CONCLUSION

GTE supplementation attenuates CCl(4)-induced hepatic oxidative stress, fibrosis, acute phase protein excretion, and hepatic dysfunction via the antioxidant and antiapoptotic defense mechanisms.

Time-dependent beneficial effect of chronic polyphenol treatment with catechin on endothelial dysfunction in aging mice

A controlled redox environment is essential for vascular cell maturation and function. During aging, an imbalance occurs, leading to endothelial dysfunction. We hypothesized that, according to the concept of hormesis, exposure to physiologic oxidative stress during the maturation phase of the endothelium will activate protective pathways involved in stress resistance. C57Bl/6 mice were treated with the polyphenol catechin for the last 3 (post-maturation) or 9 months prior study at 12 months of age. Endothelial dysfunction, assessed by acetylcholine-induced dilations of isolated renal arteries, was present at 12 months (P<0.05). Only the 3-month treatment with catechin fully prevented the decline in efficacy and sensitivity to acetylcholine (P<0.05). Splenocytes adhesion to the native endothelium, expression of CD18 and shedding of CD62L and PSGL-1 augmented in 12 months old mice (P<0.05): only 3-month catechin fully normalized adhesion and prevented the expression of adhesion molecules on splenocytes (P<0.05). Aging was associated with vascular gene alterations, which were prevented by 3-month catechin treatment (P<0.05). In contrast, 9-month catechin further increased COX-2, p22(phox) and reduced MnSOD (P<0.05). In conclusion, we demonstrate a pivotal role of cellular redox equilibrium: exposure to physiologic oxidative stress during the maturation phase of the endothelium is essential for its function.

Peritoneal adhesions in human and veterinary medicine: from pathogenesis to therapy. A review

Any peritoneal inflammatory process consequent to infections or surgical injuries may induce abdominal adhesion formation. Peritoneal adhesions are connective laciniae that develop among abdomino-pelvic organs that limit physiologic visceral motion. Consequently, fertility may be impaired, and intestinal obstruction and pelvic pain may develop, mainly in subjects that had undergone gynaecological surgery. This review illustrates the pathogenic steps of adhesiogenesis and the therapeutic scenario that evolved over the years to tackle the threat of peritoneal adhesions, both in domestic animals and in women.

In-chern-hau-tang and genipin reduces acute urinary bladder distension evoked sympathetic activation-induced hepatic dysfunction in rats

Increased norepinephrine production by acute urine retention (AUR) induced sympathetic activation may contribute to acute liver injury (ALI) via the action of hepatic vasoconstriction and increased reactive oxygen species (ROS) production. We evaluated whether In-Chern-Hau-Tang, a hepatoprotective herb medicine, and its major ingredient genipin, may ameliorate norepinephrine-induced liver injury in the rat. We determined the effects of In-Chern-Hau-Tang and genipin on norepinephrine-induced oxidative stress in the Kupffer and endothelial cells and AUR-induced ALI in the rat via a chemiluminescence analyzer, physiologic and biochemical determination and western blot. The results of in vitro study showed that genipin with efficient H(2)O(2) and HOCl scavenging activities decreased norepinephrine-enhanced ROS production in the Kupffer cell and endothelial cell cultures. AUR activated hepatic sympathetic nervous activity lead to a hepatic hypoxia/hypoperfusion, and a reduction in bile flow. AUR increased intercellular adhesion molecular 1 (ICAM-1) protein expression, and hepatic ROS production from the activated leukocyte NADPH oxidase activity subsequently leading to plasma aspartate aminotransferase (AST) elevation. Hepatic sympathetic denervation, or oral pretreatment of In-Chern-Hau-Tang or genipin for 1 week ameliorated the level in AUR-induced hepatic hypoxia/hypoperfusion, and bile stasis. Hepatic denervation, In-Chern-Hau-Yang and genipin inhibited AUR-enhanced hepatic ICAM-1 expression, hepatic ROS production, leukocyte NADPH oxidase activity and plasma AST activity. In conclusion, In-Chern-Hau-Tang along with its active component, genipin, can ameliorate AUR-induced ALI via the alleviation of oxidative stress possibly by the inhibition of sympathetic induced hypoxia/hypoperfusion and leukocyte NADPH oxidase activity.

Substance P scavenger enhances antioxidant defenses and prevents prothrombotic effects on the rat lung after acute exposure to oil smoke

Background

Airborne particulate matter, from cooking oil, smoking, engine exhaust and other sources, is associated with the development of atherosclerosis and myocardial infarction. In order to explore the cellular and molecular events following exposure of rats to lard oil smoke, we measured the generation of reactive oxygen species (ROS), substance P, cellular adhesion molecules, and thrombosis in relation to inhibitors of substance P, the NK-1 receptor, and antioxidants.

Methods

Rats were exposed to oil smoke for 120 min with or without 20 min pretreatment with lovastatin (substance P scavenger), L733060 (NK-1 receptor antagonist), vitamin E (antioxidant) or catechins (antioxidant). The levels of substance P and ROS were measured. Histological studies observed ROS damage in the form of HEL adducts. The prothrombotic effects of oil smoke exposure were measured by experimental induction of thrombosis in vivo.

Results

Oil smoke exposure significantly increased substance P levels, ROS levels, ROS damage (HEL adduct levels), and the size of experimentally induced thrombi. The pretreatments reduced all of these effects of oil smoke exposure; at many time points the reductions were statistically significant.

Conclusion

We established a connection between oil smoke exposure and thrombosis which involves substance P and its receptor, the NK-1 receptor, and ROS. This study helps establish a mechanistic explanation of how airborne particulate matter can increase the risk of cardiovascular illness.

Antioxidant effects of green tea and its polyphenols on bladder cells

Genitourinary tract inflammation/ailments affect the quality of life and health of a large segment of society. In recent years, studies have demonstrated strong antioxidant effects of green tea and its associated polyphenols in inflammatory states. This in vitro study examined the antioxidant capabilities (and putative mechanisms of action) of green tea extract (GTE), polyphenon-60 (PP-60, 60% pure polyphenols), (-)-epicatechin-3-gallate (ECG) and (-)-epigallocatechin-3-gallate (EGCG) in normal/malignant human bladder cells following catechin treatment+/-1 mM H2O2 (oxidative agent). Cell viability, apoptosis and reactive oxygen species (ROS) formation were evaluated. Our results showed that H2O2 exposure significantly reduced normal (UROtsa) and high-grade (TCCSUP, T24) bladder cancer (BlCa) cell viability compared with control-treated cells (p<0.001). No affect on low-grade RT4 and SW780 BlCa cell viability was observed with exposure to H2O2. Compared to H2O2-treated UROtsa, treatment with PP-60, ECG and EGCG in the presence of H2O2 significantly improved UROtsa viability (p<0.01), with strongest effects evoked by ECG. Additionally, though not as effective as in UROtsa cells, viability of both high-grade TCCSUP and T24 BlCa cells, in comparison to H2O2-treated cells, was significantly improved (p<0.01) by treatment with PP-60, ECG, and EGCG in the presence of H2O2. Overall, our findings demonstrate that urothelium cell death via H2O2-induced oxidative stress is mediated, in part, through superoxide (O2-.;), and potentially, direct H2O2 mechanisms, suggesting that green tea polyphenols can protect against oxidative stress/damage and bladder cell death.

Substance P acts via the neurokinin receptor 1 to elicit bronchoconstriction, oxidative stress, and upregulated ICAM-1 expression after oil smoke exposure

This study aimed to 1) assess whether substance P (SP) acts via neurokinin (NK)-1 and NK-2 receptors to stimulate neurogenic inflammation (indicated by formation of ICAM-1 expression and oxidative stress) following oil smoke exposure (OSE) in rats; and 2) determine if pretreatment with antioxidants ameliorates the deleterious effects of OSE. Rats were pretreated with NK-1 receptor antagonist CP-96345, NK-2 receptor antagonist SR-48968, vitamin C, or catechins. OSE was for 30-120 min. Rats were killed 0-8 h later. Total lung resistance (RL), airway smooth muscle activity (ASMA), lung ICAM-1 expression, neurogenic plasma extravasation (via India ink and Evans blue dye), bronchoalveolar lavage fluid SP concentrations, and reactive oxygen species formation [via lucigenin- and luminal-amplified chemiluminescence (CL)] were assessed. Lung histology was performed. SP concentrations increased significantly in nonpretreated rats following OSE in a dose-dependent manner. RL and total ASMA increased over time after OSE. Vitamin C and catechin pretreatments were associated with significantly reduced lucigenin CL 2 and 4 h after OSE. Pretreatment with catechins significantly reduced luminal CL counts 4 and 8 h after OSE. Evans blue levels were significantly reduced following 60 and 120 min of OSE in catechin- and CP-96345-pretreated rats. ICAM-1 protein expression was significantly decreased in all pretreatment groups after OSE. Thickening of the alveolar capillary membrane, focal hemorrhaging, interstitial pneumonitis, and peribronchiolar inflammation were apparent in OSE lungs. These findings suggest that SP acts via the NK-1 receptor to provoke neurogenic inflammation, oxidative stress, and ICAM-1 expression after OSE in rats.

Chronic green tea extract supplementation reduces hemodialysis-enhanced production of hydrogen peroxide and hypochlorous acid, atherosclerotic factors, and proinflammatory cytokines

BACKGROUND

Oxidative stress increases in patients with end-stage renal disease and exaggerates the related comorbidities.

OBJECTIVE

The aim of the study was to evaluate the effects of supplementation with decaffeinated green tea extract (catechins) on hemodialysis-induced reactive oxygen species, atherosclerotic disease risk factors, and proinflammatory cytokines.

DESIGN

We enrolled 6 healthy subjects and 54 hemodialysis patients for the study. First, the pharmacokinetics of one oral dose of catechins was compared between healthy subjects (n = 6) and hemodialysis patients (n = 10). Second, in the 10 hemodialysis patients, we compared the antioxidant effects of 3 different doses (0, 455, and 910 mg) of oral catechins with that of oral vitamin C (500 mg) during a hemodialysis session. Third, the other 44 hemodialysis patients participated in a 7-mo interventional study, in which 30 patients received placebo throughout and 14 patients received catechins (455 mg/d) from the third to the fifth month.

RESULTS

After one oral dose, the hemodialysis patients (n = 10) had later peaks and slower decay of plasma catechins than did the healthy subjects. In the 10 hemodialysis patients, catechin supplementation reduced hemodialysis-enhanced plasma hypochlorous acid activity more effectively than did placebo or vitamin C. Between treatments with 455 or 910 mg catechins, no significant difference was found in the reduction of plasma hypochlorous acid activity. Catechins also significantly reduced proinflammatory cytokine expression enhanced by hemodialysis. In the 7-mo interventional study, the 14 patients who received daily supplementation of catechins for 3 mo had less predialysis plasma hydrogen peroxide activity, lower hypochlorous acid activity, and lower phosphatidylcholine hydroperoxide, C-reactive protein, and proinflammatory cytokine concentrations than did the 30 hemodialysis patients who received placebo.

CONCLUSION

Catechins reduce hemodialysis-induced production of hydrogen peroxide and hypochlorous acid, atherosclerotic disease risk factors, and proinflammation.

A neurokinin-1 receptor antagonist that reduces intra-abdominal adhesion formation decreases oxidative stress in the peritoneum

Oxidative stress has been implicated in intra-abdominal adhesion formation. Substance P, a neurokinin-1 receptor (NK-1R) ligand, facilitates leukocyte recruitment and reactive oxygen species (ROS) generation. We have shown in a rat model of adhesion formation that intraperitoneal administration of a NK-1R antagonist at the time of abdominal operation reduces postoperative adhesion formation. Thus we determined the effects of NK-1R antagonist administration on peritoneal leukocyte recruitment and oxidative stress within 24 h of surgery. Adhesions were induced in Wistar rats randomly assigned to receive the antagonist or vehicle intraperitoneally. Peritoneal tissue was isolated at 2, 4, 6, and 24 h after surgery for analysis of the oxidative stress biomarkers 8-isoprostane (8-IP), protein carbonyl, NADPH oxidase, myeloperoxidase (MPO), and ICAM-1 and VCAM-1 mRNAs. Total antioxidant capacity of peritoneal fluid was also determined. MPO, NADPH oxidase, 8-IP, and protein carbonyl were elevated (P < 0.05) by 6 h. ICAM-1 mRNA was elevated (P < 0.05) by 2 h, whereas VCAM-1 levels decreased (P < 0.05) at 24 h. The NK-1R antagonist delayed the MPO rise and reduced (P < 0.05) 8-IP levels by 6 h and ICAM-1 mRNA, VCAM-1 mRNA, and protein carbonyl at 2 h. The antagonist also increased (P < 0.05) the antioxidant capacity of peritoneal fluid at all time points. These data further support a role for oxidative stress in adhesion formation and suggest that the NK-1R antagonist may limit adhesions, in part, by reducing postoperative oxidative stress through an inhibition of neutrophil recruitment and an increase in peritoneal fluid antioxidant capacity.

Combination of Wu Lin San and Shan Zha ameliorates substance P-induced hyperactive bladder via the inhibition of neutrophil NADPH oxidase activity

Substance P (SP) via neurokinin type 1 receptor activates leukocytes to produce burst release of reactive oxygen species (ROS) and increases leukocytes adhesion to the vessels in the inflamed bladder. Activation of neutrophil nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity may contribute to the neutrophil ROS production. We explored the therapeutic effect of traditional Chinese formula for urinary dysfunction, Wu Lin San (WLS), and a modified formula WLS plus Shan Zha (WLSSZ) on SP-induced bladder hyperactivity. We evaluated WLS, Shan Zha, and WLSSZ effect on neutrophils NADPH oxidase activity in SP-stimulated neutrophils in vitro, and isovolumetric cystometrogram and ROS activity in vivo in anesthetized rat bladder with SP stimulation. Our results showed that WLS, Shan Zha, and WLSSZ inhibited SP-induced NADPH oxidase activity in an order WLSSZ>Shan Zha>WLS. Exogenous SP enhanced systemic vasodilation, bladder hyperactivity and bladder ROS. One week of oral administration of WLS or WLSSZ significantly reduced SP-induced bladder ROS amount and leukocyte accumulation and ameliorated the hyperactive bladder response. The therapeutic action was better in WLSSZ than in WLS. Our results indicate that a modified formula Wu Lin San plus Shan Zha can potentially ameliorate SP-induced neurogenic inflammation possibly via the inhibition of leukocyte NADPH oxidase activity.

Thoracic Vagal Efferent Nerve Stimulation Evokes Substance P-Induced Early Airway Bronchonstriction and Late Proinflammatory and Oxidative Injury in the Rat Respiratory Tract

Electrical stimulation of efferent thoracic vagus nerve (TVN) evoked neurogenic inflammation in respiratory tract of atropine-treated rats by an undefined mechanism. We explored whether efferent TVN stimulation via substance P facilitates neurogenic inflammation via action of nuclear factor-kappaB (NF-kappaB) activation and reactive oxygen species (ROS) production. Our results showed that increased frequency of TVN stimulation concomitantly increased substance P-enhanced hypotension, and bronchoconstriction (increases in smooth muscle electromyographic activity and total pulmonary resistance). The enhanced SP release evoked the appearance of endothelial gap in silver-stained leaky venules, India-ink labeled extravasation, and accumulations of inflammatory cells in the respiratory tract, contributing to trachea plasma extravasation as well as increases in blood O (2)(-) and H(2)O(2) ROS amount. L-732138 (NK(1) receptor antagonist), SR-48968 (NK(2) receptor antagonist), dimethylthiourea (H(2)O(2) scavenger) or catechins (O (2)(-) and H(2)O(2) scavenger) pretreatment reduced efferent TVN stimulation-enhanced hypotension, bronchoconstriction, and plasma extravasation. Increased frequency of TVN stimulation significantly upregulated the expression of nuclear factor-kappaB (NF-kappaB) in nuclear protein and intercellular adhesion molecule-1 (ICAM-1) in total protein of the lower respiratory tract tissue. The upregulation of NF-kappaB and ICAM-1 was attenuated by NK receptor antagonist and antioxidants. In conclusion, TVN efferent stimulation increases substance P release to trigger NF-kappaB mediated ICAM-1 expression and O (2)(-) and H(2)O(2) ROS production in the respiratory tract.