N-Acetylcysteine Protects Bladder Epithelial Cells from Bacterial Invasion and Displays Antibiofilm Activity against Urinary Tract Bacterial Pathogens

Urinary tract infections (UTIs) affect more than 150 million individuals annually. A strong correlation exists between bladder epithelia invasion by uropathogenic bacteria and patients with recurrent UTIs. Intracellular bacteria often recolonise epithelial cells post-antibiotic treatment. We investigated whether N-acetylcysteine (NAC) could prevent uropathogenic E. coli and E. faecalis bladder cell invasion, in addition to its effect on uropathogens when used alone or in combination with ciprofloxacin. Methods: An invasion assay was performed in which bacteria were added to bladder epithelial cells (BECs) in presence of NAC and invasion was allowed to occur. Cells were washed with gentamicin, lysed, and plated for enumeration of the intracellular bacterial load. Cytotoxicity was evaluated by exposing BECs to various concentrations of NAC and quantifying the metabolic activity using resazurin at different exposure times. The effect of NAC on the preformed biofilms was also investigated by treating 48 h biofilms for 24 h and enumerating colony counts. Bacteria were stained with propidium iodide (PI) to measure membrane damage. Results: NAC completely inhibited BEC invasion by multiple E. coli and E. faecalis clinical strains in a dose-dependent manner (p < 0.01). This was also evident when bacterial invasion was visualised using GFP-tagged E. coli. NAC displayed no cytotoxicity against BECs despite its intrinsic acidity (pH ~2.6), with >90% cellular viability 48 h post-exposure. NAC also prevented biofilm formation by E. coli and E. faecalis and significantly reduced bacterial loads in 48 h biofilms when combined with ciprofloxacin. NAC visibly damaged E. coli and E. faecalis bacterial membranes, with a threefold increase in propidium iodide-stained cells following treatment (p < 0.05). Conclusions: NAC is a non-toxic, antibiofilm agent in vitro and can prevent cell invasion and IBC formation by uropathogens, thus providing a potentially novel and efficacious treatment for UTIs. When combined with an antibiotic, it may disrupt bacterial biofilms and eliminate residual bacteria.

Download Full-text

Establishment of a Persistent Escherichia coli Reservoir during the Acute Phase of a Bladder Infection

Infection and Immunity ◽

10.1128/iai.69.7.4572-4579.2001 ◽

2001 ◽

Vol 69 (7) ◽

pp. 4572-4579 ◽

Cited By ~ 474

Author(s):

Matthew A. Mulvey ◽

Joel D. Schilling ◽

Scott J. Hultgren

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Epithelial Cells ◽

Urinary Tract Infections ◽

Bacterial Attachment ◽

Bacterial Invasion ◽

E Coli ◽

Bladder Cells ◽

Tract Infections

ABSTRACT The vast majority of urinary tract infections are caused by strains of uropathogenic Escherichia coli that encode filamentous adhesive organelles called type 1 pili. These structures mediate both bacterial attachment to and invasion of bladder epithelial cells. However, the mechanism by which type 1 pilus-mediated bacterial invasion contributes to the pathogenesis of a urinary tract infection is unknown. Here we show that type 1-piliated uropathogens can invade the superficial epithelial cells that line the lumenal surface of the bladder and subsequently replicate, forming massive foci of intracellular E. coli termed bacterial factories. In response to infection, superficial bladder cells exfoliate and are removed with the flow of urine. To avoid clearance by exfoliation, intracellular uropathogens can reemerge and eventually establish a persistent, quiescent bacterial reservoir within the bladder mucosa that may serve as a source for recurrent acute infections. These observations suggest that urinary tract infections are more chronic and invasive than generally assumed.

Download Full-text

Uropathogenic Escherichia coli Triggers Oxygen-Dependent Apoptosis in Human Neutrophils through the Cooperative Effect of Type 1 Fimbriae and Lipopolysaccharide

Infection and Immunity ◽

10.1128/iai.72.8.4570-4578.2004 ◽

2004 ◽

Vol 72 (8) ◽

pp. 4570-4578 ◽

Cited By ~ 39

Author(s):

Robert Blomgran ◽

Limin Zheng ◽

Olle Stendahl

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Human Neutrophils ◽

Dependent Manner ◽

E Coli ◽

Type 1 Fimbriae ◽

The Difference ◽

Tract Infections ◽

Neutrophil Survival

ABSTRACT Type 1 fimbriae are the most commonly expressed virulence factor on uropathogenic Escherichia coli. In addition to promoting avid bacterial adherence to the uroepithelium and enabling colonization, type 1 fimbriae recruit neutrophils to the urinary tract as an early inflammatory response. Using clinical isolates of type 1 fimbriated E. coli and an isogenic type 1 fimbria-negative mutant (CN1016) lacking the FimH adhesin, we investigated if these strains could modulate apoptosis in human neutrophils. We found that E. coli expressing type 1 fimbriae interacted with neutrophils in a mannose- and lipopolysaccharide (LPS)-dependent manner, leading to apoptosis which was triggered by the intracellular generation of reactive oxygen species. This induced neutrophil apoptosis was abolished by blocking FimH-mediated attachment, by inhibiting NADPH oxidase activation, or by neutralizing LPS. In contrast, CN1016, which did not adhere to or activate the respiratory burst of neutrophils, delayed the spontaneous apoptosis in an LPS-dependent manner. This delayed apoptosis could be mimicked by adding purified LPS and was also observed by using fimbriated bacteria in the presence of d-mannose. These results suggest that LPS is required for E. coli to exert both pro- and antiapoptotic effects on neutrophils and that the difference in LPS presentation (i.e., with or without fimbriae) determines the outcome. The present study showed that there is a fine-tuned balance between type 1 fimbria-induced and LPS-mediated delay of apoptosis in human neutrophils, in which altered fimbrial expression on uropathogenic E. coli determines the neutrophil survival and the subsequent inflammation during urinary tract infections.

Download Full-text

Fosfomycin Susceptibility in Multidrug Resistant Urinary Escherichia coli Isolates

Journal of Evolution of Medical and Dental Sciences ◽

10.14260/jemds/2021/92 ◽

2021 ◽

Vol 10 (7) ◽

pp. 414-418

Author(s):

Greeshma Hareendranath

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Multidrug Resistant ◽

Diffusion Method ◽

Antibiofilm Activity ◽

E Coli ◽

Development Of Resistance ◽

Microbiological Methods ◽

Tract Infections

BACKGROUND Escherichia coli is one of the most important causes of urinary tract infections (UTIs). Increased antibiotic resistance may limit the therapeutic options for the treatment of these infections. Fosfomycin trometamol is a phosphonic acid derivative, which acts primarily by interfering with bacterial peptidoglycan synthesis with broad spectrum of activity against agents causing urinary tract infection with good antibiofilm activity and limited reports of resistance and hence is increasingly called upon for the treatment of multi drug resistant (MDR) organisms causing UTI. There are limited studies from India regarding the efficacy of this drug; so, the study was conducted to determine the in vitro efficacy of fosfomycin against uropathogenic MDR E. coli. METHODS This was a prospective study done in the Department of Microbiology, Government T.D. Medical College, Alappuzha, over a period of 1 year from April 2018 to March 2019. A total of 150 MDR urine samples were processed by routine microbiological methods and after identification of E. coli urinary isolates, antibiotic susceptibility testing was performed and results were interpreted following the Clinical and Laboratory Standards Institute guidelines (CLSI). Fosfomycin sensitivity was tested by the Kirby-Bauer disc diffusion method. RESULTS Among the 150 MDR urinary E. coli isolates, 148 (98 %) were sensitive to fosfomycin in our study. The susceptibility rate of fosfomycin was clearly higher than other commonly used drugs for UTI. All extended-spectrum beta-lactamases (ESBL) producing E. coli were sensitive to this drug. The susceptibility for nitrofurantoin was fair, whereas for ampicillin, norfloxacin, cefotaxime and trimethoprim / sulphamethoxazole was found poor. Relatively better rates of resistance were observed for parenteral antibiotics. CONCLUSIONS With an enormous increase in the bacterial pathogens resistant to first-line antibiotics, there has been a revival in the use of fosfomycin. The convenience of a single dose regimen, a good activity proven invitro, and minimal propensity for development of resistance pathogens makes fosfomycin an attractive regimen for the treatment of uncomplicated community and hospital acquired UTIs. In this regard, with the existing limited options for treating MDR organisms, fosfomycin finds its utility acting as an effective and promising option in the treatment of UTIs due to MDR pathogens in the future.

Download Full-text

Indole Derivatives Obtained from Egyptian Enterobacter sp. Soil Isolates Exhibit Antivirulence Activities against Uropathogenic Proteus mirabilis

Antibiotics ◽

10.3390/antibiotics10040363 ◽

2021 ◽

Vol 10 (4) ◽

pp. 363

Author(s):

Mai A. Amer ◽

Reham Wasfi ◽

Ahmed S. Attia ◽

Mohamed A. Ramadan

Keyword(s):

Urinary Tract ◽

Urinary Tract Infections ◽

Proteus Mirabilis ◽

Multidrug Resistant ◽

P Value ◽

Antibiofilm Activity ◽

Dependent Manner ◽

Indole Derivatives ◽

New Treatment ◽

Tract Infections

Proteus mirabilis is a frequent cause of catheter associated urinary tract infections (CAUTIs). Several virulence factors contribute to its pathogenesis, but swarming motility, biofilm formation, and urease activity are considered the hallmarks. The increased prevalence in antibiotic resistance among uropathogens is alarming and requires searching for new treatment alternatives. With this in mind, our study aims to investigate antivirulence activity of indole derivatives against multidrug resistant P. mirabilis isolates. Ethyl acetate (EtOAc) extracts from Enterobacter sp. (rhizobacterium), isolated from Egyptian soil samples were tested for their ability to antagonize the virulence capacity and biofilm activity of P. mirabilis uropathogens. Extracts of two Enterobacter sp. isolates (coded Zch127 and Cbg70) showed the highest antivirulence activities against P. mirabilis. The two promising rhizobacteria Zch127 and Cbg70 were isolated from soil surrounding: Cucurbita pepo (Zucchini) and Brassica oleracea var. capitata L. (Cabbage), respectively. Sub-minimum inhibitory concentrations (Sub-MICs) of the two extracts showed potent antibiofilm activity with significant biofilm reduction of ten P. mirabilis clinical isolates (p-value < 0.05) in a dose-dependent manner. Interestingly, the Zch127 extract showed anti-urease, anti-swarming and anti-swimming activity against the tested strains. Indole derivatives identified represented key components of indole pyruvate, indole acetamide pathways; involved in the synthesis of indole acetic acid. Additional compounds for indole acetonitrile pathway were detected in the Zch127 extract which showed higher antivirulence activity. Accordingly, the findings of the current study model the feasibility of using these extracts as promising antivirulence agent against the P. mirabilis uropathogens and as potential therapy for treatment of urinary tract infections (UTIs).

Download Full-text

Dynamin2- and endothelial nitric oxide synthase–regulated invasion of bladder epithelial cells by uropathogenic Escherichia coli

The Journal of Cell Biology ◽

10.1083/jcb.201003027 ◽

2011 ◽

Vol 192 (1) ◽

pp. 101-110 ◽

Cited By ~ 21

Author(s):

Zhimin Wang ◽

Ceba Humphrey ◽

Nicole Frilot ◽

Gaofeng Wang ◽

Zhongzhen Nie ◽

...

Keyword(s):

Nitric Oxide ◽

Escherichia Coli ◽

Epithelial Cells ◽

Uropathogenic Escherichia Coli ◽

Host Cells ◽

Bacterial Invasion ◽

E Coli ◽

Nos Inhibitors ◽

Tract Infections ◽

Endothelial Nitric Oxide

Invasion of bladder epithelial cells by uropathogenic Escherichia coli (UPEC) contributes to antibiotic-resistant and recurrent urinary tract infections (UTIs), but this process is incompletely understood. In this paper, we provide evidence that the large guanosine triphosphatase dynamin2 and its partner, endothelial nitric oxide (NO) synthase (NOS [eNOS]), mediate bacterial entry. Overexpression of dynamin2 or treatment with the NO donor S-nitrosothiols increases, whereas targeted reduction of endogenous dynamin2 or eNOS expression with ribonucleic acid interference impairs, bacterial invasion. Exposure of mouse bladder to small molecule NOS inhibitors abrogates infection of the uroepithelium by E. coli, and, concordantly, bacteria more efficiently invade uroepithelia isolated from wild-type compared with eNOS−/− mice. E. coli internalization promotes rapid phosphorylation of host cell eNOS and NO generation, and dynamin2 S-nitrosylation, a posttranslational modification required for the bacterial entry, also increases during E. coli invasion. These findings suggest that UPEC escape urinary flushing and immune cell surveillance by means of eNOS-dependent dynamin2 S-nitrosylation and invasion of host cells to cause recurrent UTIs.

Download Full-text

URINARY INFECTION AT DEPARTMENT OF UROLOGY OF HUE UNIVERSITY OF MEDICINE AND PHARMACY HOSPITAL

Journal of Medicine and Pharmacy ◽

10.34071/jmp.2018.3.16 ◽

2018 ◽

pp. 100-108

Author(s):

Dinh Khanh Le ◽

Dinh Dam Le ◽

Khoa Hung Nguyen ◽

Xuan My Nguyen ◽

Minh Nhat Vo ◽

...

Keyword(s):

Urinary Tract Infection ◽

Urinary Tract ◽

Tract Infection ◽

Urinary Tract Infections ◽

Urine Culture ◽

Clinical Manifestations ◽

University Hospital ◽

E Coli ◽

Positive Urine ◽

Tract Infections

Objectives: To investigate clinical characteristics, bacterial characteristics, drug resistance status in patients with urinary tract infections treated at Department of Urology, Hue University Hospital. Materials and Method: The study was conducted in 474 patients with urological disease treated at Department of Urology, Hue Universiry Hospital from July 2017 to April 2018. Urine culture was done in the patients with urine > 25 Leu/ul who have symptoms of urinary tract disease or infection symptoms. Patients with positive urine cultures were analyzed for clinical and bacterial characteristics. Results: 187/474 (39.5%) patients had symptoms associated with urinary tract infections. 85/474 (17.9%) patients were diagnosed with urinary tract infection. The positive urine culture rate was 45.5%. Symptoms of UTI were varied, and no prominent symptoms. E. coli accounts for the highest proportion (46.67%), followed by, Staphycoccus aureus (10.67%), Pseudomonas aeruginsa (8,0%), Streptococcus faecali and Proteus (2.67%). ESBL - producing E. coli was 69.23%, ESBL producing Enterobacter spp was 33.33%. Gram-negative bacteria are susceptible to meropenem, imipenem, amikacin while gram positive are vancomycin-sensitive. Conclusions: Clinical manifestations of urinary tract infections varied and its typical symptoms are unclear. E.coli is a common bacterium (46.67%). Isolated bacteria have a high rate of resistance to some common antibiotics especially the third generation cephalosporins and quinolones. Most bacteria are resistant to multiple antibiotics at the same time. Gram (+) bacteria are susceptible to vancomycin, and gram (-) bacteria are susceptible to cefoxitin, amikacin, and carbapenem. Key words: urinary tract infection

Download Full-text

1675. Epidemiology of Urinary Tract Infections in the United States, 2009 - 2018

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa439.1853 ◽

2020 ◽

Vol 7 (Supplement_1) ◽

pp. S823-S823

Author(s):

Kendra Foster ◽

Linnea A Polgreen ◽

Brett Faine ◽

Philip M Polgreen

Keyword(s):

United States ◽

Urinary Tract ◽

Klebsiella Pneumoniae ◽

Urinary Tract Infections ◽

Proteus Mirabilis ◽

Antibiotic Use ◽

The United States ◽

Drug Resistant ◽

E Coli ◽

Tract Infections

Abstract Background Urinary tract infections (UTIs) are one of the most common bacterial infections. There is a lack of large epidemiologic studies evaluating the etiologies of UTIs in the United States. This study aimed to determine the prevalence of different UTI-causing organisms and their antimicrobial susceptibility profiles among patients being treated in a hospital setting. Methods We used the Premier Healthcare Database. Patients with a primary diagnosis code of cystitis, pyelonephritis, or urinary tract infection and had a urine culture from 2009- 2018 were included in the study. Both inpatients and patients who were only treated in the emergency department (ED) were included. We calculated descriptive statistics for uropathogens and their susceptibilities. Multi-drug-resistant pathogens are defined as pathogens resistant to 3 or more antibiotics. Resistance patterns are also described for specific drug classes, like resistance to fluoroquinolones. We also evaluated antibiotic use in this patient population and how antibiotic use varied during the hospitalization. Results There were 640,285 individuals who met the inclusion criteria. Females make up 82% of the study population and 45% were age 65 or older. The most common uropathogen was Escherichia Coli (64.9%) followed by Klebsiella pneumoniae (8.3%), and Proteus mirabilis (5.7%). 22.2% of patients were infected with a multi-drug-resistant pathogen. We found that E. Coli was multi-drug resistant 23.8% of the time; Klebsiella pneumoniae was multi-drug resistant 7.4%; and Proteus mirabilis was multi-drug resistant 2.8%. The most common antibiotics prescribed were ceftriaxone, levofloxacin, and ciprofloxacin. Among patients that were prescribed ceftriaxone, 31.7% of them switched to a different antibiotic during their hospitalization. Patients that were prescribed levofloxacin and ciprofloxacin switched to a different antibiotic 42.8% and 41.5% of the time, respectively. Conclusion E. Coli showed significant multidrug resistance in this population of UTI patients that were hospitalized or treated within the ED, and antibiotic switching is common. Disclosures All Authors: No reported disclosures

Download Full-text

Iron Acquisition of Urinary Tract Infection Escherichia coli Involves Pathogenicity in Caenorhabditis elegans

Microorganisms ◽

10.3390/microorganisms9020310 ◽

2021 ◽

Vol 9 (2) ◽

pp. 310

Author(s):

Masayuki Hashimoto ◽

Yi-Fen Ma ◽

Sin-Tian Wang ◽

Chang-Shi Chen ◽

Ching-Hao Teng

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Caenorhabditis Elegans ◽

Large Scale ◽

Iron Acquisition ◽

Infection Model ◽

High Throughput Analysis ◽

E Coli ◽

C Elegans ◽

Tract Infections

Uropathogenic Escherichia coli (UPEC) is a major bacterial pathogen that causes urinary tract infections (UTIs). The mouse is an available UTI model for studying the pathogenicity; however, Caenorhabditis elegans represents as an alternative surrogate host with the capacity for high-throughput analysis. Then, we established a simple assay for a UPEC infection model with C. elegans for large-scale screening. A total of 133 clinically isolated E. coli strains, which included UTI-associated and fecal isolates, were applied to demonstrate the simple pathogenicity assay. From the screening, several virulence factors (VFs) involved with iron acquisition (chuA, fyuA, and irp2) were significantly associated with high pathogenicity. We then evaluated whether the VFs in UPEC were involved in the pathogenicity. Mutants of E. coli UTI89 with defective iron acquisition systems were applied to a solid killing assay with C. elegans. As a result, the survival rate of C. elegans fed with the mutants significantly increased compared to when fed with the parent strain. The results demonstrated, the simple assay with C. elegans was useful as a UPEC infectious model. To our knowledge, this is the first report of the involvement of iron acquisition in the pathogenicity of UPEC in a C. elegans model.

Download Full-text

In Vitro Coliform Resistance to Bioactive Compounds in Urinary Infection, Assessed in a Lab Catheterization Model

Applied Sciences ◽

10.3390/app11094315 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4315

Author(s):

Emanuel Vamanu ◽

Laura Dorina Dinu ◽

Cristina Mihaela Luntraru ◽

Alexandru Suciu

Keyword(s):

Urinary Tract ◽

Bioactive Compounds ◽

Urinary Tract Infections ◽

Antimicrobial Effect ◽

Biologically Active ◽

Bacterial Strains ◽

E Coli ◽

Functional Product ◽

Tract Infections

Bioactive compounds and phenolic compounds are viable alternatives to antibiotics in recurrent urinary tract infections. This study aimed to use a natural functional product, based on the bioactive compounds’ composition, to inhibit the uropathogenic strains of Escherichia coli. E. coli ATCC 25922 was used to characterize the IVCM (new in vitro catheterization model). As support for reducing bacterial proliferation, the cytotoxicity against a strain of Candida albicans was also determined (over 75% at 1 mg/mL). The results were correlated with the analysis of the distribution of biologically active compounds (trans-ferulic acid-268.44 ± 0.001 mg/100 g extract and an equal quantity of Trans-p-coumaric acid and rosmarinic acid). A pronounced inhibitory effect against the uropathogenic strain E. coli 317 (4 log copy no./mL after 72 h) was determined. The results showed a targeted response to the product for tested bacterial strains. The importance of research resulted from the easy and fast characterization of the functional product with antimicrobial effect against uropathogenic strains of E. coli. This study demonstrated that the proposed in vitro model was a valuable tool for assessing urinary tract infections with E. coli.

Download Full-text

Characterization of Anti-Bacterial Effect of the Two New Phages against Uropathogenic Escherichia coli

Viruses ◽

10.3390/v13071348 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1348

Author(s):

Lívia Slobodníková ◽

Barbora Markusková ◽

Michal Kajsík ◽

Michal Andrezál ◽

Marek Straka ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Urinary Tract Infections ◽

Therapeutic Potential ◽

Medical Intervention ◽

Uropathogenic Escherichia Coli ◽

E Coli ◽

Phage Cocktail ◽

Causative Agents ◽

Tract Infections

Urinary tract infections (UTIs) are among the events that most frequently need medical intervention. Uropathogenic Escherichia coli are frequently their causative agents and the infections are sometimes complicated by the presence of polyresistant nosocomial strains. Phage therapy is a tool that has good prospects for the treatment of these infections. In the present study, we isolated and characterized two bacteriophages with broad host specificity against a panel of local uropathogenic E. coli strains and combined them into a phage cocktail. According to genome sequencing, these phages were closely related and belonged to the Tequatrovirus genus. The newly isolated phages showed very good activity on a panel of local clinical E. coli strains from urinary tract infections. In the form of a two-phage cocktail, they were active on E. coli strains belonging to phylogroups B2 and D, with relatively lower activity in B1 and no response in phylogroup A. Our study is a preliminary step toward the establishment of a national phage bank containing local, well-characterized phages with therapeutic potential for patients in Slovakia.

Download Full-text