| 1. |
- Liuba, Petru, et al.
(author)
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Effects of Bradykinin on Aortic Endothelial Function in ApoE-Knockout Mice With Chronic Chlamydia Pneumoniae Infection.
- 2007
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In: Circulation Journal. - : Japanese Circulation Society. - 1346-9843 .- 1347-4820. ; 71:9, s. 1480-1484
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Journal article (peer-reviewed)abstract
- Background Impaired muscarinic receptor-mediated vasodilation is an important feature of early atherosclerosis. Earlier studies on apolipoprotein E-knockout mice (apoE-KO) mice suggested adverse effects of Chlamydia pneumoniae infection on the endothelial vasomotor responses of aortas to the muscarinic agonist methacholine. Using additional aorta samples the present study investigated the responses to bradykinin. Methods and Results ApoE-KO mice were repeatedly inoculated with either Chlamydia pneumoniae (C. pneumoniae) or saline. At 2, 6, and 10 weeks after the first inoculation, precontracted aorta rings from both groups were exposed to bradykinin in the absence and presence of L-NAME and diclofenac. In noninfected animals, the vasomotor responses to bradykinin were similar at all timepoints (p > 0.5). Compared with noninfected animals, the responses in infected animals tended to increase through the study period (p < 0.05 at 10 weeks). Although diclofenac and L-NAME had no effect in noninfected mice, they inhibited the responses to bradykinin in infected mice at 6 and, more markedly, 10 weeks (p < 0.05 for both). Conclusion Bradykinin stimulation of aorta endothelium from C. pneumoniae-infected apoE-KO animals appears to activate compensatory kinin receptor-related mechanisms that could involve nitric oxide and vasorelaxing prostanoids. Although the precise molecular mechanisms require further investigation, one could speculate that strategies increasing bradykinin availability might reverse the arterial dysfunction during chronic infectious disease.
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| 2. |
- Liuba, Petru, et al.
(author)
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Protective effects of simvastatin on coronary artery function in swine with acute infection.
- 2006
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In: Atherosclerosis. - : Elsevier BV. - 1879-1484 .- 0021-9150. ; 186:2, s. 331-336
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Journal article (peer-reviewed)abstract
- Background: The risk for coronary events may rise during acute infection. Perturbation in coronary endothelial function emerges as one important link. We investigated whether simvastatin could protect the coronary arterial function from the adverse effects of acute infection in swine. Methods: Coronary endothelium-dependent and -independent vasomotor responses were assessed by Doppler velocimetry in 12 Chlamydia pneunioniae-infected and 6 sham-infected swine 2 weeks after intratracheal inoculation. Half of animals from the infection group were pretreated with simvastatin (80 mg daily), while the remaining animals received placebo. The treatment was started 2 weeks prior to inoculation and Continued until the end of the Study. ANOVA was used for statistical calculations. Data are mean +/- S.D. Results: All animals inoculated with C. pneumoniae developed IgM antibodies against this organism. As compared to noninfected animals, peak-to-baseline coronary flow velocity (CFV) ratio after bradykinin was significantly decreased in infected animals regardless of statin treatment (1,p=0.01). Intracoronary 10(-6) M acetylcholine caused slight dilatory responses in both noninfected and infected-treated animals (CFV ratio: 1.6 +/- 0.2and 1.4 +/- 0.2, respectively: p > 0.1),while a velocity drop (CFV ratio: 0.7 +/- 0.1; p < 0.01 versus noninfected-infected and treated). indicating constriction, was observed in in fected-non treated animals; 10(-5) M acetylcholine caused vasoconstriction in all animals, with a significantly more prolonged response in the infected-non treated group (p < 0.01). Intracoronary adenosine and SNP induced similar dilatory responses in all groups (p > 0.5). There were no differences in markers of systemic inflammation (fibrinogen, amyloid, and CRP) and lipid profile (HDL, LDL and total cholesterol) between the groups (p > 0.2). Conclusion: Acute infection is associated with impairment of the muscarinic and kinin-related reactivity of coronary circulation. These functional abnormalities are in part prevented by simvastatin through mechanisms unrelated to lipid lowering. (c) 2005 Elsevier Ireland Ltd. All rights reserved.
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| 3. |
- Pesonen, Erkki, et al.
(author)
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Elevated infection parameters and infection symptoms predict an acute coronary event.
- 2008
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In: Therapeutic Advances in Cardiovascular Disease. - : SAGE Publications. - 1753-9447 .- 1753-9455. ; 2:6, s. 419-424
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Journal article (peer-reviewed)abstract
- BACKGROUND: The etiology and significance of flu-like symptoms often appearing before myocardial infarction should be clarified. METHODS: In a case-control study of 323 matched controls and a random sample of 110 out of 351 cases the presence of infection symptoms during the preceding four weeks before admission were asked and blood samples taken. RESULTS: Enterovirus (EV), herpes simplex virus (HSV), and Chlamydia pneumoniae IgA titers were significantly higher in cases than in controls (p<0.001, 0.008 and 0.046, respectively). Flu-like symptoms appeared significantly more often in patients than in controls the most common one being fatigue (p<0.001). In controls with fatigue, EV and HSV titers showed a trend to be higher (1.50 vs 1.45 and 4.29 vs 3.73) than in controls without fatigue but only HSV titers were statistically significantly higher (3.47 vs 3.96, p = 0.02). Even CRP and amyloid A concentrations (3.49 vs 2.08, p<0.0001 and 5.70 vs 3.77 mg/l, p = 0.003, respectively) as well as C4 (0.40 vs 0.44, p = 0.02) were higher in controls with fatigue. CONCLUSIONS: Odds ratios for a coronary event in a logistic regression model were 4.79 for fatigue and 2.72 for EV antibody levels in their fourth quartile. A linear-by-linear association test showed increasing number of single symptoms with higher EV titer quartiles (p = 0.004).
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