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1.
J Ethnopharmacol ; 150(2): 770-4, 2013 Nov 25.
Article in English | MEDLINE | ID: mdl-24120518

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional usage suggests Citrus reticulata Blanco seeds have beneficial effects against infection. The purpose of this study was to investigate the effect of Citrus reticulata on the uroepithelium and to determine the mechanisms responsible for protection against urinary tract infection (UTI). MATERIALS AND METHODS: Human bladder cell lines T24 and 5637 were employed in a cell culture infection model to determine the effects of Citrus reticulata treatment on Escherichia coli adherence and invasion of the uroepithelium. ß1 integrin and caveolin-1 mRNA expression was assessed using RT real-time PCR. ß1 integrin protein expression was confirmed by Western Blot. The effect of Citrus reticulata on bacteria was investigated using antibacterial sensitivity, yeast agglutination and biofilm assays. RESULTS: Citrus reticulata treatment decreased ß1 integrin expression and reduced bacterial invasion while adhesion of uroepithelial cells was not affected. Caveolin-1 expression was not influenced either and Citrus reticulata did neither exhibit any direct antimicrobial effect nor interfered with type 1 fimbriae binding. CONCLUSIONS: Our results show that Citrus reticulata has a protective effect on the uroepithelium as seen by reduced bacterial invasion of uroepithelial cells. These properties suggest that seeds from Citrus reticulata may have therapeutic potential in preventing UTI.


Subject(s)
Anti-Bacterial Agents/pharmacology , Citrus , Escherichia coli Infections/prevention & control , Plant Extracts/pharmacology , Urothelium/drug effects , Bacterial Adhesion/drug effects , Bacterial Load , Biofilms , Caveolin 1/genetics , Cell Line , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Escherichia coli/physiology , Escherichia coli Infections/metabolism , Escherichia coli Infections/microbiology , Humans , Integrin beta1/genetics , Seeds , Urinary Bladder , Urothelium/cytology , Urothelium/metabolism , Urothelium/microbiology
2.
Sci Transl Med ; 5(190): 190ra80, 2013 Jun 19.
Article in English | MEDLINE | ID: mdl-23785036

ABSTRACT

Epidemiological data imply a role of estrogen in the pathogenesis of urinary tract infections (UTIs), although the underlying mechanisms are not well understood. However, it is thought that estrogen supplementation after menopause decreases the risk of recurrent infections. We sought to investigate the influence of estrogen on host-pathogen interactions and the consequences for UTI pathogenesis. We analyzed urothelial cells from menstruating and postmenopausal women before and after a 2-week period of estrogen supplementation, and also studied the influence of estradiol during Escherichia coli UTI in a mouse infection model. Important findings were confirmed in two human urothelial cell lines. We identified two epithelial defense mechanisms modulated by estrogen. Estrogen induced the expression of antimicrobial peptides, thereby enhancing the antimicrobial capacity of the urothelium and restricting bacterial multiplication. In addition, estrogen promoted the expression and redistribution of cell-cell contact-associated proteins, thereby strengthening the epithelial integrity and preventing excessive loss of superficial cells during infection. These two effects together may prevent bacteria from reaching deeper layers of the urinary tract epithelium and developing reservoirs that can serve as a source for recurrent infections. Thus, this study presents some underlying mechanisms for the beneficial effect of estradiol after menopause and supports the application of estrogen in postmenopausal women suffering from recurrent UTI.


Subject(s)
Estrogens/pharmacology , Urothelium/drug effects , Urothelium/immunology , Adolescent , Adult , Aged , Animals , Antimicrobial Cationic Peptides/pharmacology , Cell Communication/drug effects , Cell Line , Cell Proliferation/drug effects , Dietary Supplements , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Epithelial Cells/pathology , Escherichia coli/drug effects , Escherichia coli/growth & development , Escherichia coli Infections/microbiology , Escherichia coli Infections/pathology , Estradiol/metabolism , Female , Humans , Intercellular Junctions/drug effects , Intercellular Junctions/metabolism , Mice , Mice, Inbred C57BL , Middle Aged , Urinary Bladder/pathology , Urothelium/microbiology , Urothelium/pathology , Young Adult
3.
J Clin Microbiol ; 50(11): 3569-74, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22915606

ABSTRACT

Urinary tract infection (UTI) is common during pregnancy and can be associated with negative outcomes for both the mother and fetus. Increased risk of infection among these patients has been attributed to physiological changes, and less focus has been placed on Escherichia coli, the most frequent causative agent. We investigated the virulence properties of isolates causing UTI in pregnant women in Sweden, Uganda, and Vietnam, as well as nonpregnant women in Sweden. Although phylogenetic group B2 was the most prevalent group, more Ugandan isolates belonged to group B1, associated with commensal strains, than isolates from other countries. Adherence to and invasion of urothelial cells, key events in the infection process, were low among group B1 isolates from pregnant Swedish women compared to those from nonpregnant patients. Similar levels of adherence and invasion were seen in isolates from pregnant women in Uganda and Vietnam. More biofilm was formed by group B2 isolates than by those belonging to group B1 and by Ugandan group B2 isolates than by those from pregnant Swedish and Vietnamese women. The antigen 43a-encoding gene, fluA(CFT073), was most prevalent among Ugandan isolates. Expression of the biofilm components, curli and cellulose, was low among all isolates. Multidrug resistance was more common among isolates from Uganda and Vietnam than among those from Swedish patients. We suggest that while bacterial virulence properties play an important role in UTI during pregnancy, physiological changes in the host may contribute more to the incidence of infection caused by less virulent E. coli.


Subject(s)
Escherichia coli Infections/microbiology , Pregnancy Complications, Infectious/microbiology , Uropathogenic Escherichia coli/isolation & purification , Virulence Factors/genetics , Adolescent , Adult , Bacterial Adhesion , Biofilms/growth & development , Drug Resistance, Multiple, Bacterial , Epithelial Cells/microbiology , Escherichia coli Infections/epidemiology , Female , Humans , Middle Aged , Molecular Typing , Phylogeny , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Sweden/epidemiology , Uganda/epidemiology , Uropathogenic Escherichia coli/classification , Uropathogenic Escherichia coli/genetics , Uropathogenic Escherichia coli/physiology , Vietnam/epidemiology , Young Adult
4.
J Ethnopharmacol ; 136(1): 111-6, 2011 Jun 14.
Article in English | MEDLINE | ID: mdl-21524700

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Labisia pumila var. alata (LPva) is a traditional medicinal herb used by Malaysian women to treat many ailments of the genitourinary tract. Its phytoestrogenic properties suggest potential to prevent recurrent urinary tract infection (UTI) in women post menopause. The aim of this study was therefore to investigate the mechanisms of action of LPva in an in vitro model of UTI. MATERIALS AND METHODS: Bladder epithelial cell lines T24 and 5637 and uropathogenic Escherichia coli (UPEC) strain CFT073 were used to model uroepithelial infection. The ability of LPva to induce programmed cell death was tested using the Annexin-V-FLUOS and TUNEL assays. Expression of caveolin-1, ß1 integrin and antimicrobial peptides HBD-2 and LL-37 in response to LPva treatment and/or infection, was assessed using RT real-time PCR. Effects on protein expression were confirmed by Western blot analysis. Sensitivity and yeast agglutination assays were employed to determine if LPva had antimicrobial activities and/or interacted with type 1 fimbriae, respectively. Finally, bacterial adherence and invasion to cells treated with LPva was examined. RESULTS: LPva induced uroepithelial apoptosis which was coupled with upregulated expression of caveolin-1 and downregulation of ß1 integrin. LPva did not exhibit direct antimicrobial properties and did not influence antimicrobial peptide levels in cells. Additionally, LPva did not interact with type 1 fimbriae and did not affect adherence in comparison to non-treated control cells. However, LPva significantly reduced the number of intracellular UPEC in bladder epithelial cells. CONCLUSIONS: Our findings suggest that LPva has beneficial applications against UPEC infection due to its ability to induce programmed cell death and reduce bacterial invasion of the uroepithelium.


Subject(s)
Apoptosis/drug effects , Escherichia coli Infections/drug therapy , Phytotherapy , Primulaceae , Urinary Bladder/drug effects , Urinary Tract Infections/drug therapy , Urothelium/drug effects , Bacterial Load/drug effects , Caveolin 1/metabolism , Cell Line , Epithelial Cells/drug effects , Epithelial Cells/microbiology , Escherichia coli/drug effects , Escherichia coli Infections/metabolism , Humans , Integrin beta1/metabolism , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Up-Regulation , Urinary Bladder/microbiology , Urinary Tract Infections/metabolism , Urinary Tract Infections/microbiology , Urothelium/cytology , Urothelium/microbiology
5.
J Med Microbiol ; 60(Pt 5): 574-581, 2011 May.
Article in English | MEDLINE | ID: mdl-21292854

ABSTRACT

We investigated the population structures of faecal Escherichia coli in 30 healthy young adults (13 males and 17 females) aged between 20 and 45 years and 29 elderly adults (14 females and 15 males) aged between 65 and 77 years. In all, 1566 strains were typed with the PhPlate system and grouped into biochemical phenotypes (BPTs). Strains with shared BPTs were further typed using randomly amplified polymorphic DNA analysis. Forty-four per cent of the strains were shared between two or more age and gender groups. Elders had a significantly higher (P<0.001) number of BPTs (mean±standard error 3.3±0.27) than younger groups (1.82±0.27). Phylogenetic affiliation and virulence-associated genes (VAGs) of the strains showed that more than 80 % of the strains belonging to dominant types belonged to phylogroups B2 and D. Amongst dominant BPTs, phylogenetic group A was significantly associated with females (P<0.0001), and elders were more likely to carry group D (P<0.0124). Elderly males had a higher prevalence of VAGs than young males (P<0.0001) and young females (P<0.0005). We conclude that there is a lower prevalence of E. coli with uropathogenic properties in healthy young adults than in elders.


Subject(s)
Escherichia coli Infections/microbiology , Escherichia coli/genetics , Escherichia coli/pathogenicity , Genes, Bacterial , Urinary Tract Infections/microbiology , Adult , Age Factors , Aged , Base Sequence , DNA Fingerprinting , DNA Primers/genetics , DNA, Bacterial/genetics , Escherichia coli/classification , Escherichia coli/isolation & purification , Feces/microbiology , Female , Humans , Male , Middle Aged , Phenotype , Phylogeny , Sex Factors , Virulence/genetics , Young Adult
6.
Microb Pathog ; 50(2): 81-6, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21075195

ABSTRACT

Four efficiently translocating Escherichia coli (TEC) strains isolated from the blood of humans (HMLN-1), pigs (PC-1) and rats (KIC-1 and KIC-2) were tested for their ability to adhere and translocate across human gut epithelial Caco-2 and HT-29 cells, to elicit a proinflammatory response and for the presence of 47 pathogenic E. coli virulence genes. HMLN-1 and PC-1 were more efficient in adhesion and translocation than rat strains, had identical biochemical phenotype (BPT) and serotype (O77:H18) and phylogenetic group (D). KIC-2 adhered more than KIC-1, belonged to different BPT and serotype but the same phylogenetic group as KIC-1. TEC strains elicited significantly higher IL-8 response in both cell lines (P < 0.05) and monocytic THP-1 (P < 0.0001) cells than non-TEC strains. KIC-2 induced the highest IL-8 response which may be associated with its immunostimulatory flagellin. Apart from adhesin genes fimH and bmaE that were carried by all strains, HMLN-1 and PC-1 carried capsule synthesis gene kpsMT III and KIC-2 carried the EAST1 toxin gene. The lack of known virulence genes and the ability of TEC to efficiently adhere and translocate whilst causing proinflammatory response suggests that these strains may carry as yet unidentified genes that enable their translocating ability.


Subject(s)
Bacterial Translocation , Escherichia coli Infections/microbiology , Escherichia coli Infections/veterinary , Escherichia coli/physiology , Escherichia coli/pathogenicity , Interleukin-8/immunology , Animals , Bacterial Adhesion , Caco-2 Cells , Escherichia coli/classification , Escherichia coli/genetics , Escherichia coli Infections/immunology , HT29 Cells , Humans , Interleukin-8/genetics , Molecular Sequence Data , Phylogeny , Rats , Rodent Diseases/immunology , Rodent Diseases/microbiology , Swine , Swine Diseases/immunology , Swine Diseases/microbiology , Virulence , Virulence Factors/genetics , Virulence Factors/immunology
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