Primary biliary cirrhosis and primary sclerosing cholangitis are of infectious origin!
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Animals↗
Biomedical subjects
T Wadström
Publications and source records attributed to T Wadström.
High intake of selenium, beta-carotene, and vitamins A, C, and E reduces growth of Helicobacter pylori in the guinea pig.
PURPOSE: Helicobacter pylori is a human gastroduodenal pathogen associated with type-B gastritis and gastric cancer. Low gastric tissue antioxidant levels are believed to increase the risk of developing gastric cancer. We investigated whether dietary antioxidant levels protect against infection and type-B gastritis in H. pylori-infected guinea pigs. METHODS: Dunkin-Hartley guinea pigs infected for 6 weeks with H. pylori were fed diets with various antioxidant levels. Stomach specimens were cultured, and gastritis was graded from 0 to 3. RESULTS: Supplementation with vitamins A, C, and E and with selenium yielded H. pylori recovery from 17% of challenged animals, compared with 43% of those fed a control diet. Gastritis was scored at 0.33 and 0.93, respectively. Supplementation with only vitamin C or astaxanthin had less effect on gastritis and recovery rate. In a second experiment, gastritis score in a group given vitamins A, C, E, and selenium and beta-carotene was 2.25 and in a control group, it was 2.57. The H. pylori recovery rate was 75 and 100%, respectively, with fewer colonies from animals given antioxidant supplementation (P < 0.05). CONCLUSIONS: A combination of antioxidants can protect against H. pylori infection in guinea pigs. In animal studies, antioxidant intake should be low to optimize development of H. pylori-associated disease. Furthermore we established that H. pylori causes severe gastritis in guinea pigs.
Animals↗
Endothelial dysfunction after repeated Chlamydia pneumoniae infection in apolipoprotein E-knockout mice.
BACKGROUND: Arterial relaxation is largely regulated by endothelial nitric oxide (NO). Its diminished activity has been associated with incipient atherosclerosis. We investigated the endothelium-dependent relaxation of aorta in apolipoprotein E-knockout (apoE-KO) mice exposed to single or repeated Chlamydia pneumoniae inoculation. METHODS AND RESULTS: Forty-eight apoE-KO mice, 8 weeks old, were inoculated intranasally with C pneumoniae (n=24) or saline (n=24) every 2 weeks over a 6-week period. Twenty mice (10 infected and 10 controls) were killed at 2 weeks and 6 weeks, respectively, after the first inoculation. The smooth muscle tone of aortic rings was measured in vitro at both time points. The norepinephrine-precontracted thoracic aortic rings were successively exposed to methacholine in the absence and presence of N:(G)-nitro-L-arginine methyl ester (L-NAME) and diclofenac. The methacholine-induced relaxation was attenuated in the infected mice at 6 weeks in both the absence and presence of L-NAME (P:<0.05 and P:<0.01, respectively). When administered together with L-NAME, diclofenac enhanced the relaxation of the L-NAME-pretreated aortas in infected mice at 2 weeks (P:<0.05) but not in noninfected mice. The relaxation response from infected mice tended to differ in the same manner at 6 weeks (P:<0.1). No intimal thickening was detected at either time point. CONCLUSIONS: C pneumoniae impairs arterial endothelial function, and the NO pathway is principally involved. Cyclooxygenase-dependent vasoconstricting products may also account for the infection-induced impaired relaxation. These findings further support the role of C pneumoniae infection in atherosclerosis development.
Alkaline Phosphatase↗
Two-dimensional electrophoretic and immunoblot analysis of cell surface proteins of spiral-shaped and coccoid forms of Helicobacter pylori.
Cell surface proteins of the human gastric pathogen Helicobacter pylori extracted during different in vitro growth phases were analyzed by one- and two-dimensional gelelectrophoresis (1-DE and 2-DE) and by 2-DE immunoblot. Broth-cultured H. pylori cells were stained with an acridine-orange dye to monitor the morphological status of the organism. In 2-day-cultures, 96% of the bacterial cells were spiral-shaped and four days later a morphological switch to coccoid forms occurred. In 10-day cultures spiral-shaped forms were not found. By 1-DE, proteins with the molecular masses of 87 and 120 kDa were detected in the 2-day cultures that disappeared in cells of 12-day cultures. A protein corresponding in size to the heat shock protein (GroEl homolog, Hsp60) and a 62 kDa protein, the ureaseB-subunit, were identified in extracted proteins of 2-, 8-, and 12-day cultures. 2-DE revealed an increased number of silver-stained spots of 8-day cultures (in average 250 spots) compared with protein extracted from 2-day cells (in average 160 spots). 2-DE immunoblots performed with sera containing antibodies to major H. pylori proteins such as the A- and B-subunits of urease and the Hsp60 showed similar reactivity to surface proteins extracted from 2-, 8-, and 12-day cultures, suggesting that these proteins remain immunologically intact. Pooled sera from infected patients absorbed with spiral-shaped cells showed an almost total blocking of the antibody reactivity to extracted coccoid proteins in 2-DE immunoblot. Eighteen spots were still visible, but this reactivity probably represents a solid overexpression by the coccoid cells of Hsp60 and ureaseB proteins and is thus difficult to block.
Acridine Orange↗
Infectious agents and primary biliary cirrhosis.
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Helicobacter↗
Modes of adherence of Helicobacter pylori to gastric surface epithelium in gastroduodenal disease: a possible sequence of events leading to internalisation.
We have investigated various modes of adherence of Helicobacter pylori to the human gastric epithelium, using transmission electron microscopy, in biopsies from nine patients with peptic ulcer disease and from four patients with chronic active gastritis. H. pylori was demonstrated in abundance in all cases within the surface mucous layer. In all ulcer- and in one out of four gastritis patients H. pylori was shown in close proximity to the gastric epithelium, with concurrent alterations in the configuration of microvilli and the apical cytoplasmic region of gastric cells. Previously described modes of H. pylori adherence were confirmed, such as loose attachment with fibrillar-like strands, firm attachment with pedestal formation, invasion in the intercellular spaces, and invagination with "cup" formation. Moreover, in many cases a fusion between the bacterial outer layer and gastric cell membranes was evident. In four cases (31%; three with active and one with past ulcer disease) viable H. pylori was found in the cytoplasm of gastric mucous cells. Our results support the hypothesis that the different modes of adherence of H. pylori represent a stepwise, possibly sequential, process which in a significant number of cases leads to internalisation of the organism. The invariable occurrence of adhesion and more frequent internalisation of H. pylori in ulcer patients may suggest a link with the pathogenesis of peptic ulcer disease.
Adult↗
Production and secretion of collagen-binding proteins from Aeromonas veronii.
Collagen-binding protein (CNBP) synthesized by Aeromonas veronii is located conserved within the subcellular fraction. The results of this study show that 98% of the total CNBP produced by Aer. veronii is present in the extracellular medium, and that the remaining CNBP is distributed either on the cell surface, within the periplasm or anchored on the outer membrane. CNBP is specifically secreted from Aer. veronii into the culture medium, because all the beta-lactamase activity was located in the cells and could be released by polymixin B extraction of periplasmic proteins. CNBP was produced at growth temperatures from 12 degrees C to 42 degrees C, but not at 4 degrees C. The findings indicate that the level of CNBP in the medium increases during the exponential growth phase and reaches a maximum during the early stationary phase. There was less CNBP production in poor nutrient MMB medium than in the rich LB nutrient medium. CNBP secretion, in contrast to aerolysin secretion, was unaffected by the exeA mutation of Aer. hydrophila. It is concluded that CNBP secretion from Aer. veronii must be achieved by a mechanism different from that reported for aerolysin secretion.
Aeromonas↗
Possible clinical importance of the transformation of Helicobacter pylori into coccoid forms.
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Drug Therapy, Combination↗
Seropositivity to Helicobacter pylori and CagA protein in schoolchildren of different ages living in urban and rural areas in southern Estonia.
OBJECTIVE: To evaluate Helicobacter pylori and CagA seropositivity in a non-selected group of schoolchildren in southern Estonia, with reference to previous studies where high seroprevalence to H. pylori (87%) and anti-CagA positivity (63%) in an adult population from the same region were found. STUDY POPULATION: A total of 421 schoolchildren selected haphazardly from a random population (n = 1018, ages 9, 12 or 15 years) and living in urban or rural areas. METHODS: H. pylori status was determined by evaluation of IgG antibodies against cell surface proteins of H. pylori, strain CCUG 17874, using standard ELISA. Anti-CagA IgGs were determined by ELISA using a recombinant fragment of CagA (CCUG 17874) as solid-phase antigen. Absorbance values > 0.3 (405 nm) were taken as a CagA-positive result based on a study of 25 sera from H. pylori-negative children. RESULTS: Of the 421 subjects, 235 (56%) were H. pylori-ELISA positive, and 109 out of the 235 (46%) were anti-CagA positive. Neither H. pylori nor CagA positivity were significantly different in girls and boys, or in children aged 9, 12 or 15 years. The H. pylori prevalence rate (118/181, 65%) as well as CagA positivity (64/181, 35%) in rural areas were higher compared with those in towns (117/240, 49% and 54/240, 22%, respectively; P = 0.001 and P = 0.005). CONCLUSION: Of schoolchildren living in southern Estonia, 56% were seropositive to H. pylori. Half of them had anti-CagA antibodies. Schoolchildren living in rural areas were infected significantly more often with CagA-seropositive strains compared with those living in towns.
Adolescent↗
The relationship between O-chain expression and colonisation ability of Helicobacter pylori in a mouse model.
The influence of lipopolysaccharide (LPS) O-polysaccharide chain production on the colonisation ability of Helicobacter pylori in four mouse models (NMRI, C57BL/6, CBA/Ca, and BALB/cA mice) was studied. H. pylori strains that produced smooth-form LPS (S-LPS) detectable in silver-stained electrophoretic gels colonised mice. In contrast, a laboratory-passaged strain G50 and the culture collection strain CCUG 17874 did not colonise mice; the former strain produced low amounts of O-chains only detectable in immunoblotting but not in silver-stained gels, whereas the latter produced rough-form LPS (R-LPS) without O-chains. Furthermore, a galE isogenic mutant, which produced R-LPS, did not colonise mice. However, after repeated broth culture, strains G50 and CCUG 17874 produced S-LPS detectable in silver-stained gels and were capable of colonising mice. Consistent with the production of O-chains, all colonising strains produced Lewis (Le) antigens, Le(x) and/or Le(y). Except for low expression of Le(y) by non-colonising G50, reflecting low production of O-chains, all other non-colonising strains and the galE mutant lacked expression of Le antigens consistent with their production of R-LPS. Lectin typing of strains supported these findings, and also showed that lectin types did not differ before and after colonisation. The low level of O-chain production and Le antigen expression by the non-colonising G50 may not be sufficient to aid colonisation. Examination of protein profiles of H. pylori strains before inoculation showed that protein expression was not significantly different between colonising and non-colonising strains. These results show that S-LPS production with O-chain expression is required by H. pylori for colonisation in a number of mouse models and that care should be taken with inoculating H. pylori strains that loss of O-chains does not occur during subculturing.
Animals↗
Astaxanthin-rich algal meal and vitamin C inhibit Helicobacter pylori infection in BALB/cA mice.
Helicobacter pylori infection in humans is associated with chronic type B gastritis, peptic ulcer disease, and gastric carcinoma. A high intake of carotenoids and vitamin C has been proposed to prevent development of gastric malignancies. The aim of this study was to explore if the microalga Haematococcus pluvialis rich in the carotenoid astaxanthin and vitamin C can inhibit experimental H. pylori infection in a BALB/cA mouse model. Six-week-old BALB/cA mice were infected with the mouse-passaged H. pylori strain 119/95. At 2 weeks postinoculation mice were treated orally once daily for 10 days (i) with different doses of algal meal rich in astaxanthin (0.4, 2, and 4 g/kg of body weight, with the astaxanthin content at 10, 50, and 100 mg/kg, respectively), (ii) with a control meal (algal meal without astaxanthin, 4 g/kg), or (iii) with vitamin C (400 mg/kg). Five mice from each group were sacrificed 1 day after the cessation of treatment, and the other five animals were sacrificed 10 days after the cessation of treatment. Culture of H. pylori and determination of the inflammation score of the gastric mucosae were used to determine the outcome of the treatment. Mice treated with astaxanthin-rich algal meal or vitamin C showed significantly lower colonization levels and lower inflammation scores than those of untreated or control-meal-treated animals at 1 day and 10 days after the cessation of treatment. Lipid peroxidation was significantly decreased in mice treated with the astaxanthin-rich algal meal and vitamin C compared with that of animals not treated or treated with the control meal. Both astaxanthin-rich algal meal and vitamin C showed an inhibitory effect on H. pylori growth in vitro. In conclusion, antioxidants may be a new strategy for treating H. pylori infection in humans.
Agar↗
Identification of Helicobacter pylori and other Helicobacter species by PCR, hybridization, and partial DNA sequencing in human liver samples from patients with primary sclerosing cholangitis or primary biliary cirrhosis.
Helicobacter pylori was identified in human liver tissue by PCR, hybridization, and partial DNA sequencing. Liver biopsies were obtained from patients with primary sclerosing cholangitis (n = 12), primary biliary cirrhosis (n = 12), and noncholestatic liver cirrhosis (n = 13) and (as controls) normal livers (n = 10). PCR analyses were carried out using primers for the Helicobacter genus, Helicobacter pylori (the gene encoding a species-specific 26-kDa protein and the 16S rRNA), Helicobacter bilis, Helicobacter pullorum, and Helicobacter hepaticus. Samples from patients with primary biliary cirrhosis and primary sclerosing cholangitis (11 and 9 samples, respectively) were positive by PCR with Helicobacter genus-specific primers. Of these 20 samples, 8 were positive with the 16S rRNA primer and 9 were positive with the 26-kDa protein primer of H. pylori. These nine latter samples were also positive by Southern blot hybridization for the amplified 26-kDa fragment, and four of those were verified to be H. pylori by partial 16S rDNA sequencing. None of the samples reacted with primers for H. bilis, H. pullorum, or H. hepaticus. None of the normal livers had positive results in the Helicobacter genus PCR assay, and only one patient in the noncholestatic liver cirrhosis group, a young boy who at reexamination showed histological features suggesting primary sclerosing cholangitis, had a positive result in the same assay. Helicobacter positivity was thus significantly more common in patients with cholestatic diseases (20 of 24) than in patients with noncholestatic diseases and normal controls (1 of 23) (P = <0.00001). Patients positive for Helicobacter genus had significantly higher values of alkaline phosphatases and prothrombin complex than Helicobacter-negative patients (P = 0.0001 and P = 0.0003, respectively). Among primary sclerosing cholangitis patients, Helicobacter genus PCR positivity was weakly associated with ulcerative colitis (P = 0.05). Significant differences related to blood group or HLA status were not found.
Alkaline Phosphatase↗
Serum antibodies to Helicobacter hepaticus and Helicobacter pylori in patients with chronic liver disease.
BACKGROUND: Bile tolerant helicobacter species such as H hepaticus and H bilis have frequently been reported to cause hepatitis in mice and other rodents. AIMS: To investigate the possible pathogenic role of these and other helicobacter species in chronic liver disease in humans. METHODS: Serum samples from 144 patients with various chronic liver diseases, 30 patients with primary sclerosing cholangitis (PSC), and 48 healthy blood donors were analysed for antibodies against H hepaticus murine strain CCUG 33637 and H pylori strain CCUG 17874. Cell surface proteins of H hepaticus were extracted by acid glycine buffer and used in an enzyme immunoassay (EIA) and immunoblot (IB). RESULTS: 56 of 144 (39%) patients with chronic liver diseases and six of 30 (20%) with PSC showed increased antibody concentrations in the H hepaticus EIA; in the H pylori EIA the numbers were 58% and 13% respectively. Compared with the healthy blood donors the antibody reactivity against the two helicobacter species was not increased (46% and 48% respectively). Patient serum samples retested by the H hepaticus EIA after absorption with sonicated H pylori cells remained positive in 12 of 37 (33%) serum samples. Distinct antibody reactivity to 55-65 kDa proteins was observed by H hepaticus IB, after the absorption step, and was considered specific for H hepaticus. These 12 serum samples were from patients with chronic alcoholic liver disease. CONCLUSIONS: Antibodies to H hepaticus, often cross reacting with H pylori, occur frequently in patients with chronic liver diseases, with no clear cut relation to specific diagnostic groups. The pathogenic significance of these findings is not known.
Adult↗
Combined seropositivity for H. pylori and C. pneumoniae is associated with age, obesity and social factors.
BACKGROUND: Manifestations of cardiovascular disease (CVD) have been associated with chronic infection by Helicobacter pylori and Chlamydia pneumoniae both in cross-sectional and in prospective follow-up cohort studies. This association may be partly due to an increase in metabolic risk factors for CVD, secondary to low-grade inflammation caused by infections. OBJECTIVE: To investigate for subjects classified according to serology titres for infection with C. pneumoniae and H. pylori associations between seropositivity and the degree of obesity and fasting insulin levels, as well as social factors. METHODS: Using methods based on those in earlier investigations of hypertensive patients in the Dalby primary-health-care district, southern Sweden, we investigated frozen samples from serum of 310 middle-aged treated hypertensives and 288 age-matched and sex-matched normotensive controls from a defined population. The baseline examination included the measurement of weight, height and blood pressure as a mean of two office readings with the subject supine. The body mass index (BMI) was calculated as kg/m2. Fasting blood samples were drawn for measurements of levels of serum lipids, blood glucose, plasma insulin and serum lipids, including total cholesterol and triglycerides. The serology titres for H. pylori were determined by an enzyme-linked immunosorbent assay. The titres for C. pneumoniae were determined by a micro-immunofluorescence method. Self-reported factors concerning social and lifestyle backgrounds were recorded. RESULTS: The group (n = 245) of subjects with combined positive serology for H. pylori and C. pneumoniae differed from the group without any positive serology (n = 57) in age (61.6 versus 57.4 years, P < 0.05) and BMI (27.3 versus 25.8 kg/m2, P < 0.05). The seropositive group also differed in terms of fasting levels of insulin (12.7 versus 11.6 pmol/l, P < 0.05), but this difference did not remain significant after adjustment for age and BMI. We detected no intergroup difference in blood pressure and levels of glucose and lipids. Members of the group with combined seropositivity reported having a lower social-class position (educational level) than that of members of the seronegative group. CONCLUSION: Subjects with combined positive serology for H. pylori and C. pneumoniae are characterized by greater age, lower social class and higher BMI, as well as higher fasting levels of insulin than those of seronegative subjects. Obesity might be a marker not only for lower social class but also for greater than normal susceptibility to such infections.
Age Factors↗
Morphologic conversion of Helicobacter pylori from spiral to coccoid form. Scanning (SEM) and transmission electron microscopy (TEM) suggest viability.
Helicobacter pylori is a pathogen associated with type B gastritis, peptic ulcer disease, gastric atrophy, and stomach cancer. H. pylori exists in two morphological forms, spirals and coccoids. The latter has been described as viable but non-cultivable. The role of the coccoid form in the pathogenesis of gastric disease is disputed. Some authors consider the coccoid form to be a degenerative or dead form of H. pylori, while others consider it a resting but still metabolically active form. This study reports the conversion from spiral to coccoid form ultrastructurally. Dense material is accumulated in the periplasmic space, the spiral bacteria bend and the outer membrane is separated from the inner cell wall layer. Remodeling of inner structures takes place, ending in the coccoid form of the bacteria with preserved light polyphosphate areas. Reduction of surface takes place by production of surface membrane vesicles, which later are squeezed off. The finding of preserved subcellular structures and intact double membranes in combination with degenerative forms suggests that some of the coccoids are viable. Scanning electron microscopy (SEM) demonstrates coccoid form of bacteria with slightly ruffled surfaces but no spiral forms.
Culture Media↗
Treatment of H. pylori infected mice with antioxidant astaxanthin reduces gastric inflammation, bacterial load and modulates cytokine release by splenocytes.
Helicobacter pylori is a gram-negative bacterium affecting about half of the world population, causing chronic gastritis type B dominated by activated phagocytes. In some patients the disease evolves into gastric ulcer, duodenal ulcer, gastric cancer or MALT lymphoma. The pathogenesis is in part caused by the immunological response. In mouse models and in human disease, the mucosal immune response is characterized by activated phagocytes. Mucosal T-lymphocytes are producing IFN-gamma thus increasing mucosal inflammation and mucosal damage. A low dietary intake of antioxidants such as carotenoids and vitamin C may be an important factor for acquisition of H. pylori by humans. Dietary antioxidants may also affect both acquisition of the infection and the bacterial load of H. pylori infected mice. Antioxidants, including carotenoids, have anti-inflammatory effects. The aim of the present study was to investigate whether dietary antoxidant induced modulation of H. pylori in mice affected the cytokines produced by H. pylori specific T-cells. We found that treatment of H. pylori infected mice with an algal cell extract containing the antioxidant astaxanthin reduces bacterial load and gastric inflammation. These changes are associated with a shift of the T-lymphocyte response from a predominant Th1-response dominated by IFN-gamma to a Th1/Th2-response with IFN-gamma and IL-4. To our knowledge, a switch from a Th1-response to a mixed Th1/Th2-response during an ongoing infection has not been reported previously.
Animals↗
Binding of extracellular matrix proteins by animal strains of staphylococcal species.
All 81 strains of Staphylococcus species isolated mainly from animals express high surface hydrophobicity as a stable property upon cultivation on blood agar. Bovine lactoferrin, human vitronectin, human fibronectin, heparin, human and bovine serum albumin were immobilized on latex beads to detect protein-binding cell surface components of 67 non-autoaggregating staphylococcal strains by a particle agglutination assay. Bovine lactoferrin was bound well by 22 strains (3 or 2) while 15 strains reacted weakly (1) and 30 did not react (0) with the lactoferrin-coated latex beads. The particle agglutination assay showed similar differences among staphylococcal strains in binding other proteins with the exception of human and bovine serum albumins for which 66 of 67 strains were negative (0). The specificity of the agglutination reaction was confirmed by a particle agglutination inhibition assay by preincubating bacterial cells with the protein (lactoferrin, vitronectin, etc.) used subsequently in particle agglutination assay. Autoaggregating strains together with some non-autoaggregating strains were selected for microtitre plate assay. According to absorbance at 570 nm, 14 strains were classified as non-adherent, 16 strains as weakly adherent and 18 strains as strongly adherent to bovine lactoferrin in microtitre plate assays. A direct correlation was found between the absorbance values at 570 nm of microtitre plate binding assay and test values obtained in particle agglutination assay. Binding of bovine lactoferrin to 81 staphylococcal strains as well as of human vitronectin and human fibronectin to a selected number of these strains was studied with radiolabeled (125I-labeled) proteins. Radiolabeled bovine lactoferrin was bound common by all except four strains (7 to 39%). Staphylococcal strains isolated from diseased pigs commonly bound 125I-labeled vitronectin (21 to 42% of the vitronectin added). Binding of vitronectin and lactoferrin was efficiently inhibited by preincubating of staphylococcal cells with sulphated carbohydrate compounds as heparin, dextran sulphate and fucoidan, but not by other non-sulphated highly charged glycoconjugates such as hyaluronic acid.
Animals↗
Effect on cell surface hydrophobicity and susceptibility of Helicobacter pylori to medicinal plant extracts.
Effects on aqueous extracts of medicinal plants on ten Helicobacter pylori strains were studied by the salt aggregation test to determine the possibility to modulate their cell surface hydrophobicity and by an agar diffusion assay for detection of antimicrobial activity. It was established that aqueous extracts of bearberry and cowberry leaves enhance cell aggregation of all H. pylori strains tested by the salt aggregation test, and the extract of bearberry possessed a remarkable bacteriostatic activity. Pure tannic acid showed a result similar to that of bearberry and cowberry extracts which contained a large amount of tannins. In contrast, extracts of wild camomile and pineapple-weed, which blocked aggregation of H. pylori, contained small amounts of tannins and did not reveal any antimicrobial activity. Tannic acid seems to be the component of bearberry and cowberry aqueous extracts with the highest activity to decrease cell surface hydrophobicity as well as in antibacterial activity against H. pylori.
Baltic States↗