Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P05231 (interleukin-6)
 23,907 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Persistent infections with Chlamydia pneumoniae have been implicated in the development of chronic diseases, such as atherosclerosis and asthma. Although azithromycin, clarithromycin, and levofloxacin are frequently used for the treatment of respiratory C. pneumoniae infections, little is known about the dose and duration of therapy needed to treat a putative chronic C. pneumoniae infection. In this study, we investigated the effect of prolonged treatment with azithromycin, clarithromycin, or levofloxacin on the viability of C. pneumoniae and cytokine production in an in vitro model of continuous infection. We found that a 30-day treatment with azithromycin, clarithromycin, and levofloxacin at concentrations comparable to those achieved in the pulmonary epithelial lining fluid reduced but did not eliminate C. pneumoniae in continuously infected HEp-2 cells. All three antibiotics decreased levels of interleukin-6 (IL-6) and IL-8 in HEp-2 cells, but this effect appeared to be secondary to the antichlamydial activity, as the cytokine levels correlated with the concentrations of microorganisms. The levels of IL-1beta, IL-4, IL-10, tumor necrosis factor alpha, and gamma interferon were too low to assess the effect of antibiotics. These data suggest that the dosage and duration of antibiotic therapy currently being used may not be sufficient to eradicate a putative chronic C. pneumoniae infection.
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PMID:Effect of prolonged treatment with azithromycin, clarithromycin, or levofloxacin on Chlamydia pneumoniae in a continuous-infection Model. 1179 50

The cardiovascular mortality rate is unacceptably high in patients with end-stage renal disease (ESRD), which suggests an accelerated atherogenic process. The cause(s) of the accelerated atherogenesis in ESRD patients are not known, though recent studies suggest that persistent infection, such as Chlamydia pneumoniae, and proinflammatory cytokines may contribute. Forty-five ESRD patients (26 men) aged 51 +/- 2 years was studied at a time-point close to start of dialysis treatment and again after about 12 months of dialysis treatment. By using noninvasive B-mode ultrasonography, we evaluated changes in a surrogate marker of atherosclerosis, calculated intima media (cIM) area, in the common carotid artery. C-reactive protein (CRP), S-albumin, and interleukin-6 (IL-6) assessed the presence of an inflammatory reaction. We also measured C pneumoniae antibodies by microimmunofluorescence, nutritional status by subjective global assessment, lipid parameters, smoking habits, and the presence of comorbidity close to the start of dialysis. No significant changes in the prevalence of carotid plaques or the mean cIM area were observed during the first 12 months of dialysis. However, because some patients showed marked increases in the cIM area during only 12 months of dialysis we divided the patients into 2 groups: 23 nonprogressors ((delta)cIM area -2.7 +/- 0.4 mm2) and 22 progressors ((delta)cIM area 3.6 +/- 0.7 mm2). Sex, age, body mass index, comorbidity, blood lipid levels, S-albumin, and CRP levels did not differ significantly between the 2 groups. On the other hand, progressors had a significantly elevated basal median level of IL-6 (5.7 versus 3.1 pg/mL; P < 0.05) and an increased prevalence of positive (> or 1/64) immunoglobulin (Ig) A antichlamydia antibodies (59% versus 17%; P < 0.01) compared with nonprogressors. A significant positive (R = 0.41; P < 0.01) correlation was found between Log IL-6 and changes in the cIM area during 12 months of dialysis. In a stepwise multiple regression model, Log IL-6 did predict, independently (P < 0.01) of traditional risk factors and C pneumoniae antibodies, changes in the cIM area. These data suggest that a persistent chlamydial infection stimulates IL-6 levels, which in turn may be involved in the pathogenesis of accelerated carotid atherosclerosis in dialysis patients.
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PMID:Elevated interleukin-6 predicts progressive carotid artery atherosclerosis in dialysis patients: association with Chlamydia pneumoniae seropositivity. 1184 Mar 67

Atherosclerotic plaques were likened histologically to healing inflammatory lesions by Russell Ross, who proposed a "response to injury" hypothesis for their formation. More recently, intraplaque inflammation has been postulated to play a role in thinning of the fibrous cap, plaque rupture, and superadded thrombosis. Potential causes for vascular injury include mechanical stress, smoke exposure, hypercholesterolemia, hyperhomocysteinemia, and chronic infection (direct, or indirect). Blood levels of inflammatory markers (e.g., C-reactive protein [CRP]; serum amyloid A [SAA]; fibrinogen; plasma viscosity; erythrocyte sedimentation rate [ESR]; leukocyte count, low serum albumin) have been associated with vascular risk factors and with prevalent and incident atherothrombotic cardiovascular disease (CVD) (coronary heart disease, [CHD]; stroke; and peripheral arterial disease). More recently, cytokines (e.g., interleukin-6 [IL-6]) and soluble adhesion molecules (e.g., intercellular adhesion molecule-1, vascular cell adhesion molecule-1) have been associated with both risk factors and disease; and offer potential therapeutic targets for nonspecific "anti-inflammatory" treatment of arterial disease. Infections associated with arterial disease include specific infections (Chlamydia pneumoniae, Helicobacter pylori) and nonspecific infections (periodontal infections, respiratory tract infections). Recent meta-analyses have shown that associations of serum markers of C. pneumoniae and H. pylori with arterial disease, risk factors, or potential intermediary mechanisms for disease are weaker than was first suggested by early reports. Likewise, further studies and meta-analyses are required to evaluate the epidemiologic relationships of CVD to periodontal infection and disease and to chronic pulmonary infections and disease. The weaker the associations between chronic infections and CVD, the larger is the size of randomized controlled trials required to establish (or exclude) a preventive effect of infection treatment. While control of chronic infection in the mouth, stomach or lungs is appropriate for its local effects, proving its efficacy in prevention of CVD presents a continuing challenge to medical science.
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PMID:The relationship between infection, inflammation, and cardiovascular disease: an overview. 1188 52

Persistent infection with Chlamydia pneumoniae (Chlamydophila pneumoniae) has been implicated in the development of atherosclerosis, asthma and other chronic diseases. However, data on treatment of C. pneumoniae infections are limited. Microbiological failure of antimicrobial therapy has been described, even after prolonged courses of treatment with azithromycin, doxycycline and erythromycin. Gemifloxacin is an enhanced-affinity fluoroquinolone with excellent activity against most common respiratory pathogens, including C. pneumoniae. The effect of prolonged treatment with gemifloxacin, compared with azithromycin, on viability of C. pneumoniae was investigated in a continuous infection model. Gemifloxacin at final con-centrations of 0.25 and 2.5 mg/L reduced the viability of C. pneumoniae by 5 log(10), which was similar to the effect of azithromycin. However, both antimicrobials failed to completely eliminate C. pneumoniae from continuously infected cells, even after 30 days of treatment. Both antibiotics decreased levels of interleukin-6 and interleukin-8 in this model, but this effect appeared to be secondary to the antichlamydial activity, as the cytokine levels correlated with the concentrations of microorganisms.
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PMID:Effect of gemifloxacin on viability of Chlamydia pneumoniae (Chlamydophila pneumoniae) in an in vitro continuous infection model. 1200 69

Infectious agents are possible stimulators of inflammation in atherogenesis. The aim of this study was to investigate if Chlamydia pneumoniae and Helicobacter pylori were associated with elevated levels of tumor necrosis factor alpha (TNFalpha) and interleukin-6 in coronary heart disease (CHD) patients (n=193) and age- and sex-matched controls (n=193) as markers of increased inflammatory activity. C reactive protein (CRP) and fibrinogen were also included. Serologic status towards the two bacteria was measured and levels of the inflammatory markers were compared between seropositives and seronegatives, each study group being evaluated separately. In CHD patients Chlamydia lipopolysaccharide (LPS) IgA seropositivity predicted elevated TNFalpha levels (P=0.009), still statistically significant after adjustment for traditional cardiovascular risk factors (P=0.005). Chlamydia LPS IgG seropositivity independently predicted fibrinogen levels in CHD patients (P=0.028), while no association between serology and inflammatory markers were observed among controls. H. pylori seropositivity alone was not associated with any increase in the inflammatory markers in any of the two groups. However, in CHD patients seropositivity to both agents predicted higher levels of TNFalpha (P=0.041), CRP (P=0.037) and fibrinogen (P=0.001) compared to double seronegativity. We conclude that C. pneumoniae LPS seropositivity may contribute to increased vascular inflammation in CHD patients, possibly even more pronounced when present in combination with H. pylori seropositivity.
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PMID:Positive Chlamydia pneumoniae serology is associated with elevated levels of tumor necrosis factor alpha in patients with coronary heart disease. 1211 4

Despite mounting evidence that psychiatric depression heightens risk for cardiac morbidity and mortality, little is known about the mechanisms responsible for this association. The present study examined the relation between depression and the expression of inflammatory risk markers implicated in the pathogenesis of coronary heart disease (CHD). One hundred adults were enrolled (68% women, 48% Caucasian, 48% African-American, mean age 30 +/- 2 years). Fifty subjects met the diagnostic criteria for clinical depression; the remaining 50 were demographically matched controls with no history of psychiatric illness. All subjects were in excellent health, defined as having no acute infectious disease, chronic medical illness, or regular medication regimen aside from oral contraceptives. The depressed subjects exhibited significantly higher levels of the inflammatory markers C-reactive protein (3.5 +/- 0.5 vs 2.5 +/- 5 mg/L, p = 0.04) and interleukin-6 (3.0 +/- 0.3 vs 1.9 +/- 0.2 pg/ml, p = 0.007) compared with control subjects. Mediational analyses aimed at identifying the pathways contributing to this association revealed that neither cigarette smoking nor subclinical infection with cytomegalovirus or Chlamydia pneumoniae had been responsible. However, depressed subjects exhibited greater body mass than control subjects, and analyses were consistent with adiposity accounting for a portion of the relation between clinical depression and increased expression of inflammatory markers. These findings indicate that in otherwise healthy adults, depression is associated with heightened expression of inflammatory markers implicated in the pathogenesis of CHD. Increased body mass appears to be partially, although not completely, responsible for this relation.
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PMID:Clinical depression and inflammatory risk markers for coronary heart disease. 1248 34

Recent studies have shown that the urogenital pathogen Chlamydia trachomatis to be a major bacterium triggering reactive arthritis (ReA), and is able to induce interleukin-6 (IL-6) production in human fibroblast-like synovial cells (FSC) in vitro. In the present study, we examined the correlation between IL-6 production and multiplication of chlamydia in FSC. All FSC from five patients secreted highly increased quantities of IL-6 in a dose-dependent and time-dependent fashion. Heat and UV inactivated chlamydia failed to enhance production of IL-6. When azithromycin was added to infected cultures of FSC at 0 or 48 h after infection, the level of IL-6 production was very low. Transmission electron microscopy of such infected cultures revealed many abnormal forms of chlamydia within the inclusions in FSC. From one step-growth curve experiments, it was suggested that C. trachomatis hardly multiplied in FSC. In contrast, in C. trachomatis infected HeLa 229 cells, chlamydia multiplied as usual, but little IL-6 production were found. These observations indicated that live chlamydia and the persistence of chlamydia may be essential for stimulating the synthesis of IL-6 in FSC.
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PMID:Infection of human fibroblast-like synovial cells with Chlamydia trachomatis results in persistent infection and interleukin-6 production. 1262 73

Cardiovascular disease (CVD) is the leading cause of mortality in end-stage renal disease (ESRD) patients and there is emerging evidence that genetic factors may contribute to the development of atherosclerosis. Myeloperoxidase (MPO) is an abundant enzyme involved in the production of free radicals. A functional G-->A single nucleotide polymorphism (SNP) has been identified at position -463, where the A allele is associated with lower MPO expression. To analyze the association between this SNP and inflammation, oxidative stress, and CVD, we studied a cohort of 155 ESRD patients (52 +/- 1 years, 62% males, 22% diabetics) shortly before the initiation of dialysis treatment. CVD was defined by medical history criteria; plasma interleukin-6 (IL-6) was used as a marker of inflammation, and plasma pentosidine as an estimation of oxidative protein damage. DNA from leukocytes was used for genotyping, performed by the pyrosequencing reaction. Only five patients (3%) had the genotype AA at the -463 position, whereas 38 (25%) had the GA and 112 (72%) had the GG genotype. No differences were noted in plasma IL-6 levels between the genotype groups, whereas the pentosidine levels were higher in the GG group (28.4 pmol/mg albumin [range, 8.5 to 123 pmol/mg albumin]) compared to the other two groups (21.4 pmol/mg albumin [range, 7.6 to 384 pmol/mg albumin; P < 0.05]). Patients with the GG genotype had a higher prevalence of positive serology for Chlamydia pneumoniae (51%) when compared to the carriers of the A allele (24%) (P < 0.05). The prevalence of CVD was lower in the AA (0%) and GA genotypes (18%), compared to the GG genotype (35%). The GG genotype was still associated with CVD after correction for age, diabetes, smoking, malnutrition, and inflammation. Our findings suggest that the -463 G-->A SNP, which supposedly results in lower MPO activity, is associated with a lower prevalence of CVD in ESRD patients. It could be speculated that this effect is mediated by a decreased oxidative stress due to lower production of free radicals.
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PMID:A functional variant of the myeloperoxidase gene is associated with cardiovascular disease in end-stage renal disease patients. 1284 78

Chlamydia pneumoniae is an obligate intracellular eubacterium and a common cause of acute and chronic respiratory tract infections. This study was designed to show the effect of C. pneumoniae on transcription factor activation in epithelial cells. The activation of transcription factors by C. pneumoniae was determined in human epithelial cell lines (HL and Calu3) by electrophoretic DNA mobility shift assay, Western blotting, and luciferase reporter gene assay. The activation of transcription factors was further confirmed by immunostaining of C. pneumoniae-infected HL cells and mock-infected controls. The effect of transcription factors on C. pneumoniae-induced host cell proliferation was assessed by [(3)H]thymidine incorporation and direct cell counting in the presence and absence of antisense oligonucleotides targeting transcription factors or the glucocorticoid receptor (GR) antagonist RU486. The activation of the GR, CCAAT-enhancer binding protein (C/EBP), and NF-kappaB was induced within 1 to 6 h by C. pneumoniae. While the interleukin-6 promoter was not activated by C. pneumoniae, the GR-driven p21((Waf1/Cip1)) promoter was increased 2.5- to 3-fold over controls 24 h after infection. C. pneumoniae dose-dependently increased the DNA synthesis of the host cells 2.5- to 2.9-fold, which was partly inhibited either by RU486 or by NF-kappaB antisense oligonucleotides. Furthermore, we provide evidence that heat-inactivated C. pneumoniae does not cause a significant increase in cell proliferation. Our results demonstrate that C. pneumoniae activates C/EBP-beta, NF-kappaB, and the GR in infected cells. However, only NF-kappaB and the GR were involved in C. pneumoniae-induced proliferation of epithelial cells.
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PMID:Chlamydia pneumoniae activates epithelial cell proliferation via NF-kappaB and the glucocorticoid receptor. 1450 May 3

Recent evidence associates inflammatory mediators with coronary heart disease. Elevation of acute-phase reaction (APR) proteins such as serum amyloid A, fibrinogen, CRP and haptoglobin in response to Helicobacter pylori (H. pylori) infection was shown to initiate gastritis and ischemic heart disease. Positive Chlamydia pneumoniae (C. pneumoniae) serology is associated with increased levels of inflammatory cytokines and tumor necrosis factor-alpha (TNF-alpha), which stimulates endothelial cell activation, procoagulant activity and angiogenesis in patients with coronary heart disease. As a final example, interleukin-6 (IL-6) has been proposed to mediate cardiovascular disorders. Public awareness of risks of excessive body weight and high levels of serum cholesterol propelled the development of synthetic dietary components such as sucrose polyester (SPE) to substitute for natural lipids. SPE is a synthetic lipid whose physical properties are similar to a natural triacylglycerol with a similar assortment of fatty acids and is resistant to lipolysis by gastric and pancreatic enzymes. Intake of SPE in lieu of natural lipids is expected to decrease absorption of essential fatty acids (EFA) and fat-soluble vitamins among other essentials. Deficiency of EFA leads to the formation of faulty cellular membranes, which is manifested as skin lesions, growth failure, erythrocyte fragility, impairment of fertility and uncoupling of oxidation and phosphorylation. Possibilities of absorption of these synthetic lipids into the circulation may represent an unexpected health hazard. We have shown that subcutaneous (sc) administration to rabbits of a range of lipolysis-resistant lipid-like sorbitol, mannitol and arabitol esters of palmitic (P) and lauric (L) acids was found to evoke a mild APR, which in humans could contribute to CHD incidence. We suggest a reversal in the commonly accepted role of SPE as a sequestor of dietary lipid: SPE may be the lipophilic solute contained within the dietary lipid solvent micelle. An alternative conclusion regarding the biological effects of excessive dose of SPE in human and pig for a short time span should be considered.
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PMID:Cardiac heart disease in the era of sucrose polyester, Helicobacter pylori and Chlamydia pneumoniae. 1496 37


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