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- Hägg, Sara, 1977-, et al.
(författare)
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Multi-Organ Expression Profiling Uncovers a Gene Module in Coronary Artery Disease Involving Transendothelial Migration of Leukocytes and LIM Domain Binding 2 : The Stockholm Atherosclerosis Gene Expression (STAGE) Study
- 2009
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Ingår i: PLoS Genetics. - : PLoS Genetics. - 1553-7390 .- 1553-7404. ; 5:12, s. e1000754-
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Tidskriftsartikel (refereegranskat)abstract
- Environmental exposures filtered through the genetic make-up of each individual alter the transcriptional repertoire in organs central to metabolic homeostasis, thereby affecting arterial lipid accumulation, inflammation, and the development of coronary artery disease (CAD). The primary aim of the Stockholm Atherosclerosis Gene Expression (STAGE) study was to determine whether there are functionally associated genes (rather than individual genes) important for CAD development. To this end, two-way clustering was used on 278 transcriptional profiles of liver, skeletal muscle, and visceral fat (n=66/tissue) and atherosclerotic and unaffected arterial wall (n=40/tissue) isolated from CAD patients during coronary artery bypass surgery. The first step, across all mRNA signals (n=15,042/12,621 RefSeqs/genes) in each tissue, resulted in a total of 60 tissue clusters (n=3958 genes). In the second step (performed within tissue clusters), one atherosclerotic lesion (n=49/48) and one visceral fat (n=59) cluster segregated the patients into two groups that differed in the extent of coronary stenosis (P=0.008 and P=0.00015). The associations of these clusters with coronary atherosclerosis were validated by analyzing carotid atherosclerosis expression profiles. Remarkably, in one cluster (n=55/54) relating to carotid stenosis (P=0.04), 27 genes in the two clusters relating to coronary stenosis were confirmed (n=16/17, P<10-27and-30). Genes in the transendothelial migration of leukocytes (TEML) pathway were overrepresented in all three clusters, referred to as the atherosclerosis module (A-module). In a second validation step, using three independent cohorts, the A-module was found to be genetically enriched with CAD risk by 1.8-fold (P<0.004). The transcription co-factor LIM domain binding 2 (LDB2) was identified as a potential high-hierarchy regulator of the A-module, a notion supported by subnetwork analysis, cellular and lesion expression of LDB2, and the expression of 13 TEML genes in Ldb2-deficient arterial wall. Thus, the A-module appears to be important for atherosclerosis development and together with LDB2 merits further attention in CAD research.
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| 2. |
- Lundman, Pia, et al.
(författare)
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A high-fat meal is accompanied by increased plasma interleukin-6 concentrations
- 2007
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Ingår i: NMCD. Nutrition Metabolism and Cardiovascular Diseases. - : Elsevier BV. - 0939-4753 .- 1590-3729. ; 17:3, s. 195-202
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND AIM: Enhanced and prolonged postprandial lipaemia is associated with coronary heart disease (CHD). However, the mechanisms linking postprandial lipaemia to the increased risk of atherosclerosis and CHD remain to be determined. The aim of the present study was to examine the effects of a high-fat meal on plasma levels of the pro-inflammatory cytokine interleukin-6 (IL-6) and cellular adhesion molecules in CHD patients and control subjects. METHODS AND RESULTS: Forty-one middle-aged men with premature CHD and 26 healthy male controls were investigated. The plasma triglyceride response to the high-fat meal was significantly greater among cases than controls. The oral fat load induced a twofold increase in plasma concentrations of IL-6, an increase that was similar in CHD patients and control subjects. No changes could be detected in plasma concentrations of cellular adhesion molecules in response to postprandial lipaemia in either CHD patients or control subjects. CONCLUSION: The results of the present study suggest that a high-fat meal affects mechanisms that induce increased inflammatory activity, which is recognised as a key modulator in the development of atherosclerosis and CHD. However, the increased levels of plasma IL-6 appear not to be determined by the magnitude of the postprandial triglyceridaemia.
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| 3. |
- Samnegård, Ann
(författare)
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Inflammation and matrix degrading proteases in coronary artery disease
- 2006
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Coronary artery disease (CAD) is a major cause of morbidity and death in the world today. The underlying process, atherosclerosis, is caused by lipid accumulation and inflammatory processes within the intimal layer of the vessel wall. Stable CAD is characterized by gradually expanding atherosclerotic plaques that narrow the lumen and, by restricting the blood flow, give rise to ischemic symptoms. Acute coronary syndromes (ACS) are usually caused by vulnerable plaques, which rupture or erode, thus initiating thrombus formation that suddenly impairs the blood flow and may cause acute myocardial infarction (MI). Inflammation is now considered to be an important feature of both atherosclerosis and atherothrombotic complications. Inflammatory cells, such as macrophages, T-cells and mast cells, are present in the atherosclerotic tissue and interact with the cells present in the vascular wall. Matrix metalloproteinases (MMPs), a family of more than 20 zinc- and calcium-dependent proteases, are capable of degrading extracellular matrix components. MMPs are involved in both the expansion of atherosclerotic plaques and the weakening of the fibrous cap, thus contributing to the development of vulnerable plaques. Inflammatory cells are suggested to be the major source of MMPs. The aim of this thesis was to evaluate the roles of MMP-3 and MMP-1 in CAD and MI, and how the expression of these MMPs may be modulated by inflammation. This was addressed by genetic analyses of known and novel polymorphisms in the MMP-3 and MMP-1 genes, biochemical analyses of circulating MMP-3, MMP-1, and various cytokines, and angiographic analyses of the extent and severity of CAD. The individual studies were conducted in three different cohorts: i) the Stockholm Coronary Artery Risk Factor (SCARF) study, a case-control study of 387 post-infarction patients and 387 healthy control persons, ii) 164 patients from the Thrombolysis and REOCclusion (TREOC) study, a longitudinal cohort study of patients with ST-elevation MI, and iii) 1177 patients from the Southampton Atherosclerosis Study (SAS) with significant CAD as assessed by coronary angiography. Scrum MMP-3 concentrations were lower in postinfarction patients compared with control subjects. Also, serum concentrations of MMP-3 were lower in the acute stage of MI (within 48 hours) than at the three months follow-up visit. Plasma MMP-1 concentrations did not differ between postinfarction patients and controls. The MMP-3 -1612 5A/6A promoter polymorphism markedly influenced the serum MMP-3 concentrations in two different cohorts of postinfarction patients and in healthy controls. Serum MMP-3 concentrations increased with the number of 6A-alleles. Furthermore, the serum MMP-3 concentration increased with the number of diseased major coronary arteries, as evaluated by coronary angiography. Women had substantially lower serum MMP-3 concentrations compared with men in the SCARF and the TREOC study cohorts. In addition, plasma MMP-1 concentrations were lower in women in the SCARF study. Studies of the MMP-1 gene revealed a haplotype effect of the MMP-1 -519 A/G and -340 C/T promoter polymorphisms on risk of MI. Compared with the A-519 -T-340 haplotype, both the A-519 -C-340 and G-519 -T-340 haplotypes showed a protective effect against MI whereas the G-519-C-340 haplotype was associated with an increased risk of MI. Functional studies of gene expression demonstrated a lower promoter activity of the A-519 -C340 and G-519 -T-340 haplotypes than of the A-519 -T-340 haplotype. Also, mRNA levels in atherosclerotic plaques were significantly lower in plaques retrieved from carriers of the A-519 -C-340 and G-519 -T-340 haplotypes than from carriers of the A-519 -T-340 haplotype. Plasma concentrations of interleukin-2 (IL-2), IL-6, IL-8, and tumour necrosis factor-alpha were higher in postinfarction patients than in controls. Furthermore, there was a difference between MMP-3 and MMP-1 concentrations as regards their respective correlations with several circulating inflammatory cytokines. Correlations were found for MMP-1, but not for MMP-3. In conclusion, the results presented in this thesis reinforce the novel alternative hypothesis of divergent effects of different MMPs in atherosclerosis and CAD. Inflammation is suggested to exert a stronger influence on MMP-1 than on MMP-3. Reduced MMP-3 concentration seems to be associated with MI, whereas increased concentration may promote progression of stable CAD.
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