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- 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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- Olofsson, P. S., et al.
(author)
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A functional interleukin-1 receptor antagonist polymorphism influences atherosclerosis development - The interleukin-1β : Interleukin-1 receptor antagonist balance in atherosclerosis
- 2009
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In: Circulation Journal. - : Japanese Circulation Society,Nihon Junkanki Gakkai. - 1346-9843 .- 1347-4820. ; 73:8, s. 1531-1536
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Journal article (peer-reviewed)abstract
- Background: Interleukin (JL)-β plays a central role in inflammation and atherosclerosis, but levels of IL-1β, its natural antagonist, IL-1Ra, and their balance in human atherosclerotic lesions, are unknown. Knowledge of protein levels in atherosclerosis and the influence of a functional IL-1Rα polymorphism would increase the understanding of atherosclerosis pathogenesis.Methods and Results: Fresh and endotoxin-stimulated explanted human atherosclerotic and normal arteries were analyzed for IL-1β, IL-1Ra and IL-1 receptor 1 (IL-1R1) using TaqMan PCR and enzyme-linked immunosorbent assay. Two hundred forty-three survivors of a first myocardial infarction were genotyped for a polymorphism in IL-1Ra and their coronary atherosclerosis analyzed by using coronary angiography. Levels of IL-1β, IL-1Ra and IL-1R1 mRNA were significantly increased in atherosclerotic arteries compared with normal arteries. Endotoxin stimulation increased IL-1β levels more than IL-1Ra levels (ie, promoted a pro-inflammatory state). A polymorphism in IL-1Ra known to increase levels of IL-1Ra was associated with decreased mean coronary artery plaque area.Conclusions: Activation of innate immunity changed the balance between IL-1β and IL-1Ra in atherosclerotic arteries towards a more pro-inflammatory state. In line with this, the presence of an IL-1Ra intron 2 polymorphism known to increase IL-1Ra levels, and possibly the IL-1Ra:IL-1β ratio, was associated with reduced coronary atherosclerosis.
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3. |
- Lin, Xue, et al.
(author)
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Controlled release of matrix metalloproteinase-1 plasmid DNA prevents left ventricular remodeling in chronic myocardial infarction of rats.
- 2009
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In: Circulation journal : official journal of the Japanese Circulation Society. - 1347-4820. ; 73:12, s. 2315-21
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Journal article (peer-reviewed)abstract
- BACKGROUND: The present study investigated whether administration of controlled release matrix metalloproteinase-1 (MMP-1) plasmid DNA prevents left ventricular (LV) remodeling in a rat chronic myocardial infarction (MI) model. METHODS AND RESULTS: Rats with a moderate-sized MI were randomized to 2 groups: injection of phosphate buffered saline (PBS) containing microspheres into the peri-infarct area (MI group, n=14) and injection of cationized gelatin microspheres incorporating MMP-1 plasmid DNA (MI+MMP-1 group, 50 microg MMP-1/20 microl; n=14). As a control group (n=14), rats received neither the coronary artery ligation nor the injection of PBS. Echocardiography, cardiac catheterization and histological studies were performed. At 2 and 4 weeks after the treatment, the MI+MMP-1 group had smaller LV end-diastolic and end-systolic dimensions, better fractional area change and smaller akinetic areas than the MI group. The LV end-systolic elastance and time constant of isovolumic relaxation were also better in the MI+MMP-1 group compared with the MI group 4 weeks after the treatment. Fibrosis evaluated with Masson's trichrome staining was less in the MI+MMP-1 group than the MI group. CONCLUSIONS: Gelatin microspheres for the controlled release of MMP-1 plasmid DNA are promising for improving cardiac remodeling and function when they are administered during the chronic phase of MI.
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