Synergistic effect between catechin and ciprofloxacin on chronic bacterial prostatitis rat model

Natural Polyphenols for Prevention and Treatment of Urinary Tract Infections

Urinary tract infections (UTIs) are the second most common type of bacterial infection worldwide. UTIs are gender-specific diseases, with a higher incidence in women. This type of infection could occur in the upper part of the urogenital tract, leading to pyelonephritis and kidney infections, or in the lower part of the urinary tract, leading to less serious pathologies, mainly cystitis and urethritis. The most common etiological agent is uropathogenic E. coli (UPEC), followed by Pseudomonas aeruginosa and Proteus mirabilis. Conventional therapeutic treatment involves the use of antimicrobial agents, but due to the dramatic increase in antimicrobial resistance (AMR), this strategy has partially lost its therapeutic efficacy. For this reason, the search for natural alternatives for UTI treatment represents a current research topic. Therefore, this review summarized the results of in vitro and animal- or human-based in vivo studies aimed to assess the potential therapeutic anti-UTI effects of natural polyphenol-based nutraceuticals and foods. In particular, the main in vitro studies were reported, describing the principal molecular therapeutic targets and the mechanism of action of the different polyphenols studied. Furthermore, the results of the most relevant clinical trials for the treatment of urinary tract health were described. Future research is needed to confirm and validate the potential of polyphenols in the clinical prophylaxis of UTIs.

Antibacterial green tea catechins from a molecular perspective: mechanisms of action and structure-activity relationships

This review summarizes the mechanisms of antibacterial action of green tea catechins, discussing the structure-activity relationship (SAR) studies for each mechanism. The antibacterial activity of green tea catechins results from a variety of mechanisms that can be broadly classified into the following groups: (1) inhibition of virulence factors (toxins and extracellular matrix); (2) cell wall and cell membrane disruption; (3) inhibition of intracellular enzymes; (4) oxidative stress; (5) DNA damage; and (6) iron chelation. These mechanisms operate simultaneously with relative importance differing among bacterial strains. In all SAR studies, the highest antibacterial activity is observed for galloylated compounds (EGCG, ECG, and theaflavin digallate). This observation, combined with numerous experimental and theoretical evidence, suggests that catechins share a common binding mode, characterized by the formation of hydrogen bonds and hydrophobic interactions with their target.

Plant-Derived Natural Antioxidants in Meat and Meat Products

The global meat industry is constantly evolving due to changes in consumer preferences, concerns and lifestyles, as well as monetary, geographical, political, cultural and religious factors. Part of this evolution is the introduction of synthetic antioxidants to increase meat and meat products' shelf-life, and reduce meat spoilage due to lipid and protein oxidation. The public perception that natural compounds are safer and healthier per se has motivated the meat industry to replace synthetic antioxidants with plant-derived ones in meat systems. Despite several promising results from in vitro and in situ studies, the effectiveness of plant-derived antioxidants against lipid and protein oxidation has not been fully documented. Moreover, the utility, usability, marketability and potential health benefits of natural antioxidants are not yet fully proven. The present review aims to (i) describe the major chemical groups of plant-derived antioxidants and their courses of action; (ii) present the application of spices, herbs and fruits as antioxidants in meat systems; and (iii) discuss the legislative framework, future trends, challenges and limitations that are expected to shape their acceptance and mass exploitation by the meat industry.

Opportunities and challenges in managing antibiotic resistance in bacteria using plant secondary metabolites

Development of antibiotic resistance (ABR) in bacteria and its multidimensional spread is an emerging global threat that needs immediate attention. Extensive antibiotics (AB) usage results in development of ABR in bacteria by target modification, production of AB degrading enzymes, porin modifications, efflux pumps overexpression, etc. To counter this, apart from strict regulation of AB use and behavioural changes, research and development (R&D) of newer antimicrobials are in place. One such emerging approach to combat ABR is the use of structurally and functionally diverse plant secondary metabolites (PSMs) in combination with the conventional AB. Either the PSMs are themselves antimicrobial or they potentiate the activity of the AB through a range of mechanisms. However, their use is lagging due to poor knowledge of mode of action, structure-activity relationships, pharmacokinetics, etc. This review paper discussed the opportunities and challenges in managing ABR using PSMs. Mechanisms of ABR development in bacteria and current strategies to counter them were studied and the areas where PSMs can play an important role were highlighted. The use of PSMs, both as an anti-resistance and anti-virulence agent in combination therapy to counter multi-drug resistance along with their mechanisms of action, has been discussed in detail. The difficulties in the commercialisation of PSMs and strategies to overcome them along with future priority areas of research have also been given. Following the given R&D path will definitely help in better understanding and utilising the full potential of PSMs in solving the problem of antimicrobial resistance (AMR).

Natural Phenolic Compounds for the Control of Oxidation, Bacterial Spoilage, and Foodborne Pathogens in Meat

Alternative technologies for long-term preservation, quality assurance, and safety of meat are continuously pursued by the food industry to satisfy the demands of modern consumers for nutritious and healthy meat-based products. Naturally occurring phenolic compounds are considered promising substances by the meat industry for their antioxidant and antimicrobial properties, while consumers seem to embrace them for their claimed health benefits. Despite the numerous in vitro and in situ studies demonstrating their beneficial effects against meat oxidation, spoilage, and foodborne pathogens, wide application and commercialization has not been yet achieved. Major obstacles are still the scarcity of legislative framework, the large variety of meat-based products and targeted pathogens, the limited number of case-specific application protocols and the questionable universal efficiency of the applied ones. The objectives of the present review are i) to summarize the current knowledge about the applications of naturally occurring phenols in meat and meat-based products, emphasizing the mechanisms, determinants, and spectrum of their antioxidant and antimicrobial activity; ii) to present state-of-the-art technologies utilized for the application of phenolic compounds in meat systems; and iii) to discuss relevant regulation, limitations, perspectives, and future challenges for their mass industrial use.

Pharmacological Interventions for Bacterial Prostatitis

Prostatitis is a common urinary tract condition but bring innumerable trouble to clinicians in treatment, as well as great financial burden to patients and the society. Bacterial prostatitis (acute bacterial prostatitis plus chronic bacterial prostatitis) accounting for approximately 20% among all prostatitis have made the urological clinics complain about the genital and urinary systems all over the world. The international challenges of antibacterial treatment (emergence of multidrug-resistant bacteria, extended-spectrum beta-lactamase-producing bacteria, bacterial biofilms production and the shift in bacterial etiology) and the transformation of therapeutic strategy for classic therapy have attracted worldwide attention. To the best of our knowledge currently, there is not a single comprehensive review, which can completely elaborate these important topics and the corresponding treatment strategy in an effective way. This review summarizes the general treatment choices for bacterial prostatitis also provides the alternative pharmacological therapies for those patients resistant or intolerant to general treatment.

The Effect of Flavonoids on Chronic Prostatitis: A Meta-analysis of Published Randomized Controlled Trials

OBJECTIVE

To assess the effect of flavonoids on chronic prostatitis, a meta-analysis of randomized controlled trials was performed.

METHODS

Through using subject word and random word, PubMed, Scopus, Web of Science, and Cochrane Library were searched for related records up to July 2018. The response rate and National Institutes of Health-Chronic Prostatitis Symptom Index (NIH-CPSI) were used to evaluate the therapeutic efficacy of the flavonoids. The Cochrane handbook for systematic reviews of interventions version was used to evaluate the quality of included studies. The model of determining odds ratio (OR) was chose according to the value of I².

RESULTS

A total of 11 studies involving 975 subjects (experiment 516, control 459) were included. The overall OR of response rate was 0.31 (95%CI 0.11-0.89, P = 0.03). At the subgroup analysis, the OR of response rate of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) was 0.57 (95%CI 0.18-1.77, P = 0.33), while the OR of response rate of chronic bacterial prostatitis (CBP) was 0.08 (95%CI 0.02-0.33, P = 0.0005). The OR of response rate of CP/CPPS (control was placebo) was 0.29 (95%CI 0.16-0.52, P < 0.0001). The overall OR of baseline NIH-CPSI was -0.1 (95%CI -0.61-0.41, P = 0.70). The overall OR of posttreatment NIH-CPSI was -6.96 (95%CI -8.32∼ -5.60, P < 0.00001).

CONCLUSIONS

This meta-analysis indicates that the flavonoids may be clinically beneficial through significantly improving the response rate and NIH-CPSI in chronic prostatitis patients and short-lasting antibiotics therapy in association with the flavonoids could be a better choose for CBP. Moreover, the flavonoids therapy has an excellent safety profile with minor adverse effects.

Experimental rat prostatitis caused by Trichomonas vaginalis infection

BACKGROUND

Trichomonas vaginalis (T. vaginalis) is the most common sexually transmitted parasite. It has been detected in prostatic tissue of patients with prostatitis and reported to be associated with chronic prostatitis and benign prostatic hyperplasia as well as prostate cancer. Recently, experimental rodent models of prostatitis induced by pathogen infection have been developed. However, there have so far been no reports of prostatitis caused by T. vaginalis infection in animals. Here, we investigated whether infection with T. vaginalis via the rat urethra could cause prostatitis.

METHODS

T. vaginalis was injected into prostate through urethra of rat (Wistar rats), and the rats were killed 1, 2, or 4 weeks later. The presence of T. vaginalis trophozoites in the rat prostates was examined by immunohistochemistry, and pathological changes of the prostate were observed by hematoxylin-eosin staining and evaluated by grading from 0 to 5 for inflammatory cell infiltration, acinar changes, and interstitial fibrosis. Infiltrated mast cells were observed by toluidine blue staining of rat prostate tissue. Chemokine C-C motif ligand 2 (CCL2) levels of the rat prostates were measured by ELISA.

RESULTS

T. vaginalis trophozoites were observed in acini in the prostates of the injected rats. The prostate tissues had higher pathological scores, and 83% (5/6) and 100% (6/6) of the ventral and dorsolateral lobes (n = 6), respectively, were inflamed. Infiltration and degranulation of mast cells were observed at higher rates in prostate sections of the T. vaginalis-infected rats. Also, prostate tissues of the injected rats had increased CCL2 levels.

CONCLUSIONS

Injection of T. vaginalis in rats caused prostatitis as revealed by pathologic changes, mast cell infiltration and increased CCL2 production. Therefore, this study provides the first evidence that T. vaginalis infection in rats causes prostatitis.

Antimicrobial metabolites from Saraca asoca impairs the membrane transport system and quorum-sensing system in Pseudomonas aeruginosa

This study was conducted to explore the antimicrobial mechanism of metabolites from Saraca asoca (SA1) using differential proteomics and metabolic profile of Pseudomonas aeruginosa after treatment with effective sub-MIC dose of 312 µg/mL. SA1 fraction was found to contain antibacterial metabolites catechol, protocatechuic acid, and epigallocatechin gallate. Proteome analysis revealed 33 differentially expressed proteins after SA1 treatment. Protein network analysis showed that SA1 treatment upregulated the DNA topological and metabolic processes. Furthermore, it revealed that T2SS, cellular component biogenesis, and response to chemical stimuli were inhibited by SA1 treatment, supported by down-regulated Na⁺/H⁺ antiporter, SdeX, ompK, and trbD proteins. Statistical analysis of mass data revealed the altered level of 20 metabolites includes HSLs, PQS, rhamnolipid, and pyocyanin. Proteome and metabolome results showed that treatment impaired cell membrane functions and quorum-sensing system. It was further confirmed by increased MDA (3.95 fold), and rhamnolipids (4.3 fold) production and, therefore, oxidative stress (36.9%) after SA1 treatment.

Antimicrobial activities of widely consumed herbal teas, alone or in combination with antibiotics: an in vitro study

Background

Because of increasing antibiotic resistance, herbal teas are the most popular natural alternatives for the treatment of infectious diseases, and are currently gaining more importance. We examined the antimicrobial activities of 31 herbal teas both alone and in combination with antibiotics or antifungals against some standard and clinical isolates of Pseudomonas aeruginosa, Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Enterococcus faecalis, methicillin susceptible/resistant Staphylococcus aureus and Candida albicans.

Methods

The antimicrobial activities of the teas were determined by using the disk diffusion and microbroth dilution methods, and the combination studies were examined by using the microbroth checkerboard and the time killing curve methods.

Results

Rosehip, rosehip bag, pomegranate blossom, thyme, wormwood, mint, echinacea bag, cinnamon, black, and green teas were active against most of the studied microorganisms. In the combination studies, we characterized all the expected effects (synergistic, additive, and antagonistic) between the teas and the antimicrobials. While synergy was observed more frequently between ampicillin, ampicillin-sulbactam, or nystatine, and the various tea combinations, most of the effects between the ciprofloxacin, erythromycin, cefuroxime, or amikacin and various tea combinations, particularly rosehip, rosehip bag, and pomegranate blossom teas, were antagonistic. The results of the time kill curve analyses showed that none of the herbal teas were bactericidal in their usage concentrations; however, in combination with antibiotics they showed some bactericidal effect.

Discussion

Some herbal teas, particularly rosehip and pomegranate blossom should be avoided because of their antagonistic interactions with some antibiotics during the course of antibiotic treatment or they should be consumed alone for their antimicrobial activities.

Inhibition of green tea and the catechins against 1-deoxy-d-xylulose 5-phosphate reductoisomerase, the key enzyme of the MEP terpenoid biosynthetic pathway

1-Deoxy-d-xylulose 5-phosphate reductoisomerase (DXR) is the first committed enzyme in the MEP terpenoid biosynthetic pathway and also a validated antimicrobial target. Green tea which is rich in polyphenolic components such as the catechins, possesses a plenty of pharmacological activities, in particular an antibacterial effect. To uncover the antibacterial mechanism of green tea and to seek new DXR inhibitors from natural sources, the DXR inhibitory activity of green tea and its main antimicrobial catechins were investigated in this study. The results show that the raw extract of green tea and its ethyl acetate fraction are able to suppress DXR activity explicitly. Further determination of the DXR inhibitory capacity of eight catechin compounds demonstrates that the most active compound is gallocatechin gallate that is able to inhibit around 50% activity of DXR at 25μM. Based on these data, the primary structure-activity relationship of the catechins against DXR is discussed. This study would be very helpful to elucidate the antimicrobial mechanism of green tea and the catechins and also would be very useful to direct the rational utilization of them as food additives.

Efficacy of Compound Therapy by Ginseng and Ciprofloxacin on Bacterial Prostatitis

OBJECTIVE

Genitourinary tract infections play a significant role in male infertility. Infections of reproductive sex glands, such as the prostate, impair function and indirectly affect male fertility. The general aim of this study is to investigate the protective effect of Korean red ginseng (KRG) on prostatitis in male rats treated with ciprofloxacin (CIPX).

MATERIALS AND METHODS

In this experimental study, we randomly divided 72 two male Wistar rats into 9 groups. The groups were treated as follows for 10 days: i. Control (no medication), ii. Sham [(normal saline injection into the vas deferens and oral administration of phosphate-buffered saline (PBS)], iii. Ginseng, iv. CPIX, v. CIPX+ginseng, vi. Uropathogenic Escherichia coli (E. coli) (UPEC), vii. UPEC+ginseng, viii. UPEC+CIPX, and ix. UPEC+ginseng+CIPX. The rats were killed 14 days after the last injection and the prostate glands were removed. After sample preparation, routine histology was performed using hematoxylin and eosin staining. The terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) method was used to determine the presence of apoptotic cells.

RESULTS

The severity score for acinar changes and inflammatory cell infiltration in the UPEC+CIPX group did not significantly different from the UPEC group. However this score significantly decreased in the UPEC+CIPX+ginseng group compared to the UPEC group. Apoptotic index of all ginseng treated groups significantly decreased compared to the UPEC and CPIX groups.

CONCLUSION

These results suggested that ginseng might be an effective adjunct in CIPX treatment of prostatitis. The combined use ginseng and CIPX was more effective than ginseng or CIPX alone.

Synergistic anti-Campylobacter jejuni activity of fluoroquinolone and macrolide antibiotics with phenolic compounds

The increasing resistance of Campylobacter to clinically important antibiotics, such as fluoroquinolones and macrolides, is a serious public health problem. The objective of this study is to investigate synergistic anti-Campylobacter jejuni activity of fluoroquinolones and macrolides in combination with phenolic compounds. Synergistic antimicrobial activity was measured by performing a checkerboard assay with ciprofloxacin and erythromycin in the presence of 21 phenolic compounds. Membrane permeability changes in C. jejuni by phenolic compounds were determined by measuring the level of intracellular uptake of 1-N-phenylnaphthylamine (NPN). Antibiotic accumulation assays were performed to evaluate the level of ciprofloxacin accumulation in C. jejuni. Six phenolic compounds, including p-coumaric acid, sinapic acid, caffeic acid, vanillic acid, gallic acid, and taxifolin, significantly increased the susceptibility to ciprofloxacin and erythromycin in several human and poultry isolates. The synergistic antimicrobial effect was also observed in ciprofloxacin- and erythromycin-resistant C. jejuni strains. The phenolic compounds also substantially increased membrane permeability and antibiotic accumulation in C. jejuni. Interestingly, some phenolic compounds, such as gallic acid and taxifolin, significantly reduced the expression of the CmeABC multidrug efflux pump. Phenolic compounds increased the NPN accumulation in the cmeB mutant, indicating phenolic compounds may affect the membrane permeability. In this study, we successfully demonstrated that combinational treatment of C. jejuni with antibiotics and phenolic compounds synergistically inhibits C. jejuni by impacting both antimicrobial influx and efflux.

Biofilm-related infections: bridging the gap between clinical management and fundamental aspects of recalcitrance toward antibiotics

Surface-associated microbial communities, called biofilms, are present in all environments. Although biofilms play an important positive role in a variety of ecosystems, they also have many negative effects, including biofilm-related infections in medical settings. The ability of pathogenic biofilms to survive in the presence of high concentrations of antibiotics is called "recalcitrance" and is a characteristic property of the biofilm lifestyle, leading to treatment failure and infection recurrence. This review presents our current understanding of the molecular mechanisms of biofilm recalcitrance toward antibiotics and describes how recent progress has improved our capacity to design original and efficient strategies to prevent or eradicate biofilm-related infections.

Effects of green tea on Escherichia coli as a uropathogen

Escherichia coli is the most common cause of urinary tract infections. The development of antibiotic resistance in E. coli is an important problem. Finding alternative antimicrobial agents from plant extracts has received growing interest. Camellia sinensis is a safe, nontoxic, cheap beverage that has been reported to have antimicrobial effects against various pathogenic bacteria including E. coli. Polyphenolic components of green tea ( lǜ chá) have antibacterial activity. Catechins also have synergistic effect with antibiotics such as chloramphenicol, amoxicillin, sulfamethoxazole, azithromycin, levofloxacin, gentamycin, methicillin, naldixic acid, and, especially ciprofloxacin. In this review, all experimental studies that evaluated the effect of green tea on E. coli were collected. Data from in vitro studies on the antimicrobial effects of green tea are promising, but human data are currently lacking. In vivo studies on antibacterial effects of green tea and evaluating the efficacy of its catechins in the treatment of urinary tract infection are needed.

The Antimicrobial Activity of (-)-Epigallocatehin-3-Gallate and Green Tea Extracts against Pseudomonas aeruginosa and Escherichia coli Isolated from Skin Wounds

Background

Skin infections with Gram-negative bacteria are sometimes challenging to treat, because these bacteria show multidrug resistance against commonly used antibiotics and patients with Gram-negative bacterial infection overall have deteriorated in conditions in many cases. Studies have shown that epigallocatechin gallate (EGCG) and green tea extracts (GTE) inhibit the growth of several Gram-positive bacteria species.

Objective

The purpose of this study was to investigate the minimum inhibitory concentrations (MICs) of EGCG and GTE in Pseudomonas aeruginosa and Escherichia coli, and assess the use of these chemicals as an alternative or adjunct topical antimicrobial agent against P. aeruginosa and E. coli with multidrug resistance.

Methods

The MICs of EGCG, GTE, and other tested antibiotics were measured and compared to determine the antibacterial efficacy and the differences in pattern of resistance.

Results

The P. aeruginosa and E. coli strains used in this study showed multidrug resistance. EGCG inhibited the growth of P. aeruginosa at a MIC level of 200~400 µg/ml. The MIC of GTE was a 1 : 16 dilution for P. aeruginosa. EGCG showed antimicrobial activity against E. coli at a MIC of 400 µg/ml. In the case of GTE, the MIC was a dilution between 1:8 and 1:4 for E. coli.

Conclusion

EGCG and GTE showed potential as alternative or adjunct topical antimicrobial agents for infections that are resistant to traditional antibiotic therapy.

Tea catechins as a potential alternative anti-infectious agent

Besides well-known health benefits, green tea catechins exert antimicrobial and antiviral activities against a variety of infectious agents. Although the detailed mechanism of the antimicrobial activity of tea catechins remains to be explored, the broad-spectrum activity of catechins may involve common target(s), such as the cell membrane, in addition to specific targets for each pathogen. This extends to antiviral activities, where many pronounced activities were reported for enveloped viruses. Yet, the effectiveness of tea catechins as antimicrobials is compromised by relative chemical instability and poor bioavailability. Whether tea catechins will emerge as a viable option as alternative medicine or as a synergistic combination therapy with pre-existing antivirals or antibiotics must therefore depend on a method of delivery that ensures its stability and bioavailability. However, green tea may provide an option for mitigating the health and economic burdens associated with emerging and re-emerging infectious diseases, especially considering the paucity of effective control measures. Considering the zoonotic nature of newly arising infectious diseases, the dual use of green tea components in both humans and livestock may reduce animal-human transmission, which would complement the current management of infectious diseases.

Tea: A native source of antimicrobial agents

Tea (Camellia sinensis) is one of the most popular nonalcoholic beverages, consumed by over two-thirds of the world's population because of its refreshing, mild stimulant and medicinal properties. It is processed in different ways in different parts of the world to give green, black, oolong, and pu-erh tea. Among all tea polyphenols, epigallocatechin-3-gallate has been responsible for much of the health promoting abilities of tea including anti-inflammatory, antimicrobial, antitumour, anti-oxidative, protection from cardiovascular disease, anti-obesity, and anti-aging properties. In the present review, the antibacterial, antiviral, and antifungal activities of different types of tea and their polyphenols are reported, highlighting their mechanisms of action and structure–activity relationship. Moreover, considering that the changing patterns of infectious diseases and the emergence of microbial strains resistant to current antibiotics, there is an urgent need to find out new potent antimicrobial agents as adjuvants to antibiotic therapy. The synergistic effect of tea polyphenols in combination with conventional antimicrobial agents against clinical multidrug-resistant microorganisms has also been discussed in this review.

From in vitro to in vivo Models of Bacterial Biofilm-Related Infections

The influence of microorganisms growing as sessile communities in a large number of human infections has been extensively studied and recognized for 30–40 years, therefore warranting intense scientific and medical research. Nonetheless, mimicking the biofilm-life style of bacteria and biofilm-related infections has been an arduous task. Models used to study biofilms range from simple in vitro to complex in vivo models of tissues or device-related infections. These different models have progressively contributed to the current knowledge of biofilm physiology within the host context. While far from a complete understanding of the multiple elements controlling the dynamic interactions between the host and biofilms, we are nowadays witnessing the emergence of promising preventive or curative strategies to fight biofilm-related infections. This review undertakes a comprehensive analysis of the literature from a historic perspective commenting on the contribution of the different models and discussing future venues and new approaches that can be merged with more traditional techniques in order to model biofilm-infections and efficiently fight them.

Preventive effect of ginsenoid on chronic bacterial prostatitis

Empirical antibiotic therapy is the preferred primary treatment modality for chronic bacterial prostatitis (CBP). However, this method of treatment has a low success rate and long-term therapy may result in complications and the appearance of resistant strains. Therefore a new alternative method for the prevention of CBP is necessary. There are several reports that ginsenoid has a preventive effect on urinary tract infection (UTI). To evaluate the preventive effect of ginsenoid on CBP compared to conventional antibiotics, we carried out an experiment in a rat model of the disease. Four groups of adult male Wistar rats were treated with the following medications: (1) control (no medication), (2) ciprofloxacin, (3) ginsenoid, and (4) ciprofloxacin/ginsenoid. All medications were given for 4 weeks, and then we created a CBP model in the animals by injecting an Escherichia coli Z17 (O2:K1;H(-)) suspension into the prostatic urethra. After 4 weeks, results of microbiological cultures of prostate and urine samples, as well as histological findings of the prostate in each group were analyzed. The microbiological cultures of the prostate samples demonstrated reduced bacterial growth in all experimental groups compared with the control group. Histopathological examination showed a significantly decreased rate of infiltration of inflammatory cells into prostatic tissue and decreased interstitial fibrosis in the ginsenoid group compared with the control group. Inhibition of prostate infection was greater in the group receiving both ginsenoid and antibiotic than in the single-medication groups. Although the findings of this study suggest a preventive effect of ginsenoid, preventive methods for CBP are still controversial.

Preventive effect of selenium on chronic bacterial prostatitis

The antibiotic treatment rate of chronic bacterial prostatitis (CBP) is low, and long-term administration can result in adverse events and bacterial resistance. For these reasons, a new preventive modality, which can replace traditional antibiotic therapy, is required. To evaluate the preventive effect of selenium on CBP, the pre-treatments were divided into four groups, administered for 4 weeks, as follows: (1) control, (2) ciprofloxacin, (3) selenium, and (4) ciprofloxacin and selenium. Then, drip infusion of a bacterial suspension (Escherichia coli Z17, O2:K1; H-) into the prostatic urethra of Wistar rats was conducted to induce CBP. In 4 weeks, the results of microbiological culture of prostate and urine samples as well as histological findings of the prostate in each group were analyzed. Selenium decreased bacterial infection significantly; the decrease in infiltration rate of inflammatory cells into prostate tissues in the selenium group was similar to that in the control group. The effect of hindering bacterial infection on prostate tissue was greater in the group administered both selenium and an antibiotic than in other groups given only one of the agents. Although the findings of this study suggest that selenium can have a preventive effect against the occurrence of CBP, methods to prevent CBP are still controversial.

Does finasteride have a preventive effect on chronic bacterial prostatitis? Pilot study using an animal model

AIM

To evaluate the preventive effect of finasteride on chronic bacterial prostatitis (CBP), Wistar rats were divided into four groups: control, ciprofloxacin, finasteride, and ciprofloxacin/finasteride.

METHODS

All drug pretreatments were conducted for 4 weeks, and then experimental CBP was induced by instillation of a bacterial suspension (Escherichia coli Z17 O2:K1;H-).

RESULTS

After 4 weeks, results of microbiological cultures of prostate and urine samples as well as histological findings of the prostate in each group were analyzed. Finasteride significantly reduced bacterial infection and decreased inflammatory cell infiltration in prostatic tissue compared with the control group. The group given both finasteride and antibiotic showed a greater inhibition of bacterial infection in the tissue than those given either finasteride or antibiotic alone.

CONCLUSION

Our experiments suggest the possibility that finasteride has a preventive effect on development of CBP, although there is as yet no consensus on the mechanism of this effect.

Anti-inflammatory and antimicrobial effects of nanocatechin in a chronic bacterial prostatitis rat model

Chronic bacterial prostatitis (CBP) is one of the most common relapsing urinary tract infection (UTI) in males. Catechin, an extract of green tea, is known to have anti-inflammatory and antimicrobial effects against various bacteria. However, catechin can be easily degenerated during digestion, and this may result in decreased absorption into the body. Nanocatechin is catechin coated with hydroxypropyl methyl cellulose by nanotechnology. It reduces degeneration during digestion and enhances absorption of catechin into the body. We evaluated the anti-inflammatory and antimicrobial effect of nanocatechin on CBP and also analyzed plasma concentration of catechins to evaluate absorptivity in an animal model. Forty rats demonstrating CBP were randomly divided into four groups: control, ciprofloxacin, catechin, and nanocatechin. After treatment, the results of microbiological culture of prostate and urine samples as well as histological findings of the prostate in each group were analyzed. Plasma concentration of catechins in catechin and nanocatechin groups was compared. The use of ciprofloxacin, catechin, and nanocatechin showed statistically significant decrease in bacterial growth and improvement in prostatic inflammation compared with the control group. The nanocatechin group showed statistically significant decrease in bacterial growth and improvement in prostatic inflammation compared with the catechin group. Plasma concentrations of epicatechin, gallocatechin gallate, and epigallocatechin gallate were significantly higher in the nanocatechin group than those in the catechin group. These results suggest that nanocatechin has better antimicrobial and anti-inflammatory effects on rat CBP than catechin due to higher absorption into the body.

Genitourinary pain syndromes, prostatitis, and lower urinary tract symptoms

The overlap of pain and urinary voiding symptoms is common for urologic patients. The etiology of these syndromes is frequently multifactorial and due to disorders of the bladder and/or prostate. The evaluation and treatment of these syndromes continues to evolve. Here we summarize the general approach to evaluation and treatment of these pain syndromes.

Cystone - An ayurvedic polyherbal formulation inhibits adherence of uropathogenic E. coli and modulates H2O2-induced toxicity in NRK-52E cells

Gentamicin is a widely used antibiotic for the treatment of adverse urinary tract infections (UTI), which in turn causes nephrotoxicity to uroepithelial cells and hence an alternative safe herbal remedy is much desired to compensate these toxic effects. The bacterial adhesion to the uroepithelial cells is the primary step in UTI and it induces various immunogenic reactions leading to the generation of reactive oxygen species (ROS), which are detrimental to the cells survival. Inhibition of bacterial adherence to urinary tract epithelial cells has been assumed to account for the beneficial action ascribed to cystone (an ayurvedic polyherbal formulation) in the prevention of UTI. In this study, we have examined the effect of cystone on the adherence of pathogenic [2-¹⁴C]-acetate labeled Escherichia coli (MTCC-729) to rat proximal renal tubular cells (NRK-52E cells). Further, the antioxidant property of cystone was studied using hydrogen peroxide (400 μM) as a pro-oxidant in NRK-52E cells. The results showed that cystone inhibited the adherence of E. coli to NRK-52E cells significantly. Additionally cystone effectively combats the toxicity induced by H₂O₂ in NRK-52E cells. The cytoprotective effect of cystone is brought about by inhibiting lipid peroxidation by 36% in cells treated with cystone compared to H₂O₂-treated cells without cystone. The antioxidant enzymes catalase, glutathione were increased by 53% and 68% respectively and superoxide dismutase activity was increased 3-fold. The glutathione content was significantly increased by 2.4-fold in NRK-52E cells treated with cystone compared to H₂O₂ control group. These results suggest that cystone effectively inhibits bacterial adherence to NRK-52E cells and attenuates H₂O₂-induced toxicity in NRK-52E cells by inhibiting lipid peroxidation and increasing the antioxidant defense mechanism.

Chronic prostatitis: management strategies

The National Institutes of Health (NIH) has redefined prostatitis into four distinct entities. Category I is acute bacterial prostatitis. It is an acute prostatic infection with a uropathogen, often with systemic symptoms of fever, chills and hypotension. The treatment hinges on antimicrobials and drainage of the bladder because the inflamed prostate may block urinary flow. Category II prostatitis is called chronic bacterial prostatitis. It is characterized by recurrent episodes of documented urinary tract infections with the same uropathogen and causes pelvic pain, urinary symptoms and ejaculatory pain. It is diagnosed by means of localization cultures that are 90% accurate in localizing the source of recurrent infections within the lower urinary tract. Asymptomatic inflammatory prostatitis comprises NIH category IV. This entity is, by definition, asymptomatic and is often diagnosed incidentally during the evaluation of infertility or prostate cancer. The clinical significance of category IV prostatitis is unknown and it is often left untreated. Category III prostatitis is called chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). It is characterized by pelvic pain for more than 3 of the previous 6 months, urinary symptoms and painful ejaculation, without documented urinary tract infections from uropathogens. The syndrome can be devastating, affecting 10-15% of the male population, and results in nearly 2 million outpatient visits each year. The aetiology of CP/CPPS is poorly understood, but may be the result of an infectious or inflammatory initiator that results in neurological injury and eventually results in pelvic floor dysfunction in the form of increased pelvic muscle tone. The diagnosis relies on separating this entity from chronic bacterial prostatitis. If there is no history of documented urinary tract infections with a urinary tract pathogen, then cultures should be taken when patients are symptomatic. Prostatic localization cultures, called the Meares-Stamey 4 glass test, would identify the prostate as the source for a urinary tract infection in chronic bacterial prostatitis. If there is no infection, then the patient is likely to have CP/CPPS. For healthcare providers, the focus of therapy is symptomatic relief. The first therapeutic measure is often a 4- to 6-week course of a fluoroquinolone, which provides relief in 50% of men and is more efficacious if prescribed soon after symptoms begin. Second-line pharmacotherapy involves anti-inflammatory agents for pain symptoms and alpha-adrenergic receptor antagonists (alpha-blockers) for urinary symptoms. Potentially more effective is pelvic floor training/biofeedback, but randomized controlled trials are needed to confirm this. Third-line agents include 5alpha-reductase inhibitors, glycosaminoglycans, quercetin, cernilton (CN-009) and saw palmetto. For treatment refractory patients, surgical interventions can be offered. Transurethral microwave therapy to ablate prostatic tissue has shown some promise. The treatment algorithm provided in this review involves a 4- to 6-week course of antibacterials, which may be repeated if the initial course provides relief. Pain and urinary symptoms can be ameliorated with anti-inflammatories and alpha-blockers. If the relief is not significant, then patients should be referred for biofeedback. Minimally invasive surgical options should be reserved for treatment-refractory patients.

Green Nanotechnology from Tea: Phytochemicals in Tea as Building Blocks for Production of Biocompatible Gold Nanoparticles

Phytochemicals occluded in tea have been extensively used as dietary supplements and as natural pharmaceuticals in the treatment of various diseases including human cancer. Results on the reduction capabilities of phytochemicals present in tea to reduce gold salts to the corresponding gold nanoparticles are presented in this paper. The phytochemicals present in tea serve the dual roles as effective reducing agents to reduce gold and also as stabilizers to provide robust coating on the gold nanoparticles in a single step. The Tea-generated gold nanoparticles (T-AuNPs), have demonstrated remarkable in vitro stability in various buffers including saline, histidine, HSA, and cysteine solutions. T-AuNPs with phytochemical coatings have shown significant affinity toward prostate (PC-3) and breast (MCF-7) cancer cells. Results on the cellular internalization of T-AuNPs through endocytosis into the PC-3 and MCF-7 cells are presented. The generation of T-AuNPs follows all principles of green chemistry and have been found to be non toxic as assessed through MTT assays. No 'man made' chemicals, other than gold salts, are used in this true biogenic green nanotechnological process thus paving excellent opportunities for their applications in molecular imaging and therapy.

Nitric oxide as a target of complementary and alternative medicines to prevent and treat inflammation and cancer

Nitric oxide (NO) and associated reactive nitrogen species (RNS) are involved in many physiological functions. There has been an ongoing debate to whether RNS can inhibit or perpetuate chronic inflammation and associated carcinogenesis. Although the final outcome depends on the genetic make-up of its target, the surrounding microenvironment, the activity and localization of nitric oxide synthase (NOS) isoforms, and overall levels of NO/RNS, evidence is accumulating that in general, RNS drive inflammation and cancers associated with inflammation. To this end, many complementary and alternative medicines (CAMs) that work in chemoprevention associated with chronic inflammation, are inhibitors of excessive NO observed in inflammatory conditions. Here, we review recent literature outlining a role of NO/RNS in chronic inflammation and cancer, and point toward NO as one of several targets for the success of CAMs in treating chronic inflammation and cancer associated with this inflammation.

Evaluation of toxicity of green tea catechins with 90-day dietary administration to F344 rats

Green tea catechins (GTC), polyphenols extracted from the stalks and leaves of Camellia sinensis, are found in the different types of tea beverages and as antioxidant additives to many foods, snacks, fats and fatty oils. As a part of their safety assessment, subchronic toxicity was investigated in male and female F344 rats with dietary administration at concentrations of 0 (control), 0.3%, 1.25% and 5.0% for 90 days. The average daily intakes of GTC in each group were 180, 764 and 3525mg/kg body weight/day, respectively for males, and 189, 820 and 3542mg/kg body weight/day, respectively for females. No mortality or obvious clinical signs were observed throughout the experimental period but body weights were reduced from week 1 to the end of the experiment in 5.0% males. In serum biochemistry, alanine transaminase and alkaline phosphatase in 5.0% males and females and aspartate transaminase in 5.0% females were increased, together with the relative liver weights in both sexes receiving 5.0%. Although decreases were evident for total cholesterol in 0.3-5.0% males and triglycerides in 1.25% and 5.0% males and 5.0% females, these changes were not considered to be adverse. Hematology and histopathological observation revealed no GTC-related toxicological changes. Based on above findings, the no observed adverse effect level (NOAEL) of GTC was estimated to be 1.25% (764mg/kg body weight/day for males and 820mg/kg body weight/day for females).

Control of Clostridium perfringens spores by green tea leaf extracts during cooling of cooked ground beef, chicken, and pork

We investigated the inhibition of Clostridium perfringens spore germination and outgrowth by two green tea extracts with low (green tea leaf powder [GTL]; 141 mg of total catechins per g of green tea extract) and high (green tea leaf extract [GTE]; 697 mg of total catechins per g of extract) catechin levels during abusive chilling of retail cooked ground beef, chicken, and pork. Green tea extracts were mixed into the thawed beef, chicken, and pork at concentrations of 0.5, 1.0, and 2.0% (wt/ wt), along with a heat-activated (75 degrees C for 20 min) three-strain spore cocktail to obtain a final concentration of approximately 3 log spores per g. Samples (5 g) of the ground beef, chicken, and pork were then vacuum packaged and cooked to 71 degrees C for 1 h in a temperature-controlled water bath. Thereafter, the products were cooled from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h, resulting in significant increases (P < 0.05) in the germination and outgrowth of C. perfringens populations in the ground beef, chicken, and pork control samples without GTL or GTE. Supplementation with 0.5 to 2% levels of GTL did not inhibit C. perfringens growth from spores. In contrast, the addition of 0.5 to 2% levels of GTE to beef, chicken, and pork resulted in a concentration-and time-dependent inhibition of C. perfringens growth from spores. At a 2% level of GTE, a significant (P < 0.05) inhibition of growth occurred at all chill rates for cooked ground beef, chicken, and pork. These results suggest that widely consumed catechins from green tea can reduce the potential risk of C. perfringens spore germination and outgrowth during abusive cooling from 54.4 to 7.2 degrees C in 12, 15, 18, or 21 h of cooling for ground beef, chicken, and pork.

Experimental rodent models of prostatitis: limitations and potential

Prostatitis is a polyetiological inflammation of the prostate gland in men characterized by pelvic pain, irritative voiding symptoms, and sexual dysfunction. Histologically prostatitis is characterized by poly- and mononuclear cell infiltrates (neutrophils, lymphocytes, macrophages and plasma cells) in the stromal connective tissue around the acini or ducts. Prostatitis is an important worldwide health problem in men. The pathogenesis and diagnostic criteria for the condition are obscure, with the result that the development of management programs for this condition has been hindered. Animal model(s) might be useful in elucidating mechanisms involved in the molecular pathogenesis of chronic nonbacterial prostatitis and chronic pelvic pain syndrome. Given that prostatitis might have a multifactorial etiology, several animal models with unique features may prove helpful. This review examines a number of experimental rodent models of prostatitis and evaluates their advantages and limitations.

Overview of antibacterial, antitoxin, antiviral, and antifungal activities of tea flavonoids and teas

Tea leaves produce organic compounds that may be involved in the defense of the plants against invading pathogens including insects, bacteria, fungi, and viruses. These metabolites include polyphenolic compounds, the six so-called catechins, and the methyl-xanthine alkaloids caffeine, theobromine, and theophylline. Postharvest inactivation of phenol oxidases in green tea leaves prevents oxidation of the catechins, whereas postharvest enzyme-catalyzed oxidation (fermentation) of catechins in tea leaves results in the formation of four theaflavins as well as polymeric thearubigins. These substances impart the black color to black teas. Black and partly fermented oolong teas contain both classes of phenolic compounds. A need exists to develop a better understanding of the roles of polyphenolic tea compounds in food and medical microbiology. This overview surveys and interprets our present knowledge of activities of tea flavonoids and teas against foodborne and other pathogenic bacteria, virulent protein toxins produced by some of the bacteria, virulent bacteriophages, pathogenic viruses and fungi. Also covered are synergistic, mechanistic, and bioavailability aspects of the antimicrobial effects. Further research is suggested for each of these categories. The herein described findings are not only of fundamental interest, but also have practical implications for nutrition, food safety, and animal and human health.

Antimicrobial properties of green tea catechins

Extracts of leaves from the tea plant Camellia sinensis contain polyphenolic components with activity against a wide spectrum of microbes. Studies conducted over the last 20 years have shown that the green tea polyphenolic catechins, in particular (-)-epigallocatechin gallate (EGCg) and (-)-epicatechin gallate (ECg), can inhibit the growth of a wide range of Gram-positive and Gram-negative bacterial species with moderate potency. Evidence is emerging that these molecules may be useful in the control of common oral infections, such as dental caries and periodontal disease. Sub-inhibitory concentrations of EGCg and ECg can suppress the expression of bacterial virulence factors and can reverse the resistance of the opportunistic pathogen Staphylococcus aureus to beta-lactam antibiotics. For example, relatively low concentrations of ECg can sensitize methicillin-resistant S. aureus (MRSA) clinical isolates to levels of oxacillin that can be readily achieved in clinical practice. Catechin gallates such as ECg intercalate into phopsholipid bilayers and it is likely that they affect both virulence and antibiotic resistance by perturbing the function of key processes associated with the bacterial cytoplasmic membrane.