Mast cells associate with T-cells and neointimal microvessels in giant cell arteritis.

OBJECTIVE: Mast cells (MCs) are known to be involved in the neovascularization and regulation of T cell responses. However, the presence of MCs in giant cell arteritis (GCA) is unknown. This prompted us to study the presence and phenotype of MCs in GCA. METHODS: Human GCA specimens collected for diagnostic purposes were examined with immunohistochemistry. Double immunostainings of MC tryptase with cathepsin G, vascular endothelial cell growth factor (VEGF), CD3, and CD31/D34 were performed. RESULTS: Double immunostainings showed that activated tryptase-, cathepsin G- and VEGF-expressing MCs associate with CD3+ T cells and CD31/CD34+ neointimal neovessels in the GCA lesions. CONCLUSIONS: The results suggest that MCs may contribute to the pathogenesis of GCA putatively by regulating the functions of other inflammatory cells and resident vessel wall cells. Importantly, MCs promote neovascularization, which is considered as a prerequisite for the neointimal thickening in GCA.

Once-weekly 22microg subcutaneous IFN-beta-1a in secondary progressive MS: a 3-year follow-up study on brain MRI measurements and serum MMP-9 levels.

OBJECTIVE: To study the effect of weekly injected subcutaneous interferon (IFN)-beta-1a 22 microg on the extent of brain lesions on magnetic resonance imaging (MRI) and the level of serum matrix metalloproteinase (MMP)-9 in patients with secondary progressive multiple sclerosis (SPMS). SUBJECTS AND METHODS: All the 28 Finnish patients participating in the Nordic multicentre trial on the clinical efficacy of weekly IFN-beta-1a (Rebif) 22 microg in SPMS were studied neurologically and by volumetric MRI during a 3-year follow-up. The levels of MMP-9 in serum were measured over the 3-year study. RESULTS: There was no obvious effect on the number of contrast medium-enhancing lesions, the volume of T1 or T2 lesions or level of serum MMP-9, nor was any effect detected on the relapse rate and the Expanded Disability Status Scale (EDSS). Brain atrophy progression was not affected by the treatment. CONCLUSION: The lack of effect on MRI, clinical outcomes or the levels of MMP-9 indicates that subcutaneous administration of low-dose low-frequency IFN-beta-1a is insufficient in controlling either the inflammatory constitutes or the neurodegenerative changes of advanced SPMS.

Estrogen receptor-1 genotype is related to coronary intima thickness in young to middle-aged women.

OBJECTIVE: The incidence of coronary disease in premenopausal women is about one-half that in men of similar age. The estrogen receptor-1 (ESR1, c.454-397T>C) CC variant genotype is associated with the severity of coronary artery disease (CAD) and an increased risk of myocardial infarction in men. The purpose of the present study was to investigate whether this ESR1 CC variant also disposes to atherosclerosis in women in terms of increased total coronary artery intima thickness. MATERIAL AND METHODS: A total of 125 forensic autopsy cases of women aged 15 to 49 years were investigated. The thickness of the coronary intima, which reflects the severity of atherosclerosis, was measured by computerized image analysis. The ESR1 c.454-397T>C genotype was determined by polymerase chain reaction (PCR). RESULTS: The mean intima thicknesses in the three genotype groups were 428+/-298 microm (TT), 494+/-371 microm (CT) and 636+/-436 microm (CC). We found that, on average, women with the CC genotype had a thicker coronary intima compared with that of women with the TT genotype, even after adjusting for age and body mass index (BMI) (p = 0.030). The intermediate group (TC) did not significantly differ from either the CC or the TT genotype group in this respect. CONCLUSION: Our results point to the importance of ESR1 genotype in relation to cardiovascular disease susceptibility.

Effects of oxidized low- and high-density lipoproteins on gene expression of human macrophages.

OBJECTIVE: Oxidized low-density lipoprotein (ox-LDL) is a major factor in foam cell formation, whereas the role of oxidized high-density lipoprotein (ox-HDL) in this process is not known. The objective of the present study was to examine the effects of ox-LDL and ox-HDL on the gene expression of cultured human macrophages. MATERIAL AND METHODS: Gene expression of human macrophages was studied after incubation for 1 day and 3 days with native and oxidized LDL and HDL using cDNA expression array. Expression of granulocyte-macrophage colony-stimulating factor 1, which was constantly up-regulated by ox-LDL and down-regulated by ox-HDL after 1- and 3 days of incubation in cDNA microarray experiments, was verified by quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: Genes that showed altered expression were divided into six groups; 1) lipid metabolism, 2) inflammation, growth and hemostasis, 3) matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases, 4) enzymes, 5) structural and binding proteins and 6) annexins. CONCLUSIONS: The microarray method was found to be applicable in analyzing changes in gene expression induced by oxidized lipoproteins in cultured human macrophages. Our results reflect different functional roles of ox-LDL and ox-HDL in foam cell formation.

Serum matrix metalloproteinase-9 and venous bypass graft occlusion.

OBJECTIVE: The primary results after coronary artery bypass grafting are good, but early clinical events as a result of graft occlusion are still a problem. Early occlusions are thought to be due to thrombosis or fibrointimal hyperplasia superimposed by thrombosis, but the etiology of these phenomena is not fully understood. Matrix metalloproteinase-9 has been suggested to have a role in graft occlusion ex vivo. MATERIAL AND METHODS: We investigated whether the level of serum matrix metalloproteinase-9 reflects its proposed role in occlusion of vein grafts. The study population consisted of 30 men with a history of myocardial infarction and 31 men without myocardial infarction who had undergone coronary artery bypass grafting. All the men were asymptomatic. RESULTS: Among the patients with no previous myocardial infarction, serum matrix metalloproteinase-9 level was significantly higher in those with graft occlusion than in those without occlusion (54.0+/-11.0 microg/L and 41.7+/-10.4 microg/L, respectively, p = 0.006), and it correlated positively with the number of occluded grafts (R = 0.55, p = 0.001). In the patients with myocardial infarction, this effect was not detected. CONCLUSIONS: Serum matrix metalloproteinase-9 reflected the occurrence of vein graft occlusion in subjects with no previous history of myocardial infarction.

HDL enhances oxidation of LDL in vitro in both men and women.

BACKGROUND: Oxidative modification of low-density lipoprotein (LDL) is a key event in the oxidation hypothesis of atherogenesis. Some in vitro experiments have previously suggested that high-density lipoprotein (HDL) co-incubated with LDL prevents Cu2+-induced oxidation of LDL, while some other studies have observed an opposite effect. To comprehensively clarify the role of HDL in this context, we isolated LDL, HDL2 and HDL3 from sera of 61 free-living individuals (33 women and 28 men). RESULTS: When the isolated LDL was subjected to Cu2+-induced oxidation, both HDL2 and HDL3 particles increased the rate of appearance and the final concentration of conjugated dienes similarly in both genders. Oxidation rate was positively associated with polyunsaturated fatty acid content of the lipoproteins in that it was positively related to the content of linoleate and negatively related to oleate. More saturated fats thus protected the lipoproteins from damage. CONCLUSION: We conclude that in vitro HDL does not protect LDL from oxidation, but is in fact oxidized fastest of all lipoproteins due to its fatty acid composition, which is oxidation promoting.

Serum fatty acids in postinfarction middle-aged men.

There is a multitude of data showing that coronary heart disease is affected by the quality of dietary fat. The fatty acid composition of serum lipids has been shown to reflect that of the diet. It is likely that, after myocardial infarction, both the health-care professionals and the patients themselves pay more attention to dietary guidelines. In order to assess the correctness of this assumption, we compared the composition of serum fatty acids in 40 male subjects with a history of myocardial infarction (MI) with that of 40 age-matched controls, both from the FINRISK study. The percentage composition of fatty acids of total serum lipids was analysed by gas chromatography. In comparison with the control group, the MI group had higher body mass index (BMI), a higher prevalence of diabetes, higher level of serum triglycerides and a lower level of serum high-density lipoprotein (HDL) cholesterol, all indicators of the metabolic syndrome. The MI group had higher proportions of serum palmitic (16:0) and oleic acids (18:1), and a lower proportion of linoleic (18:2 n-6) acid than the control group. The metabolic syndrome is accompanied by an elevated level of serum insulin, which is known to enhance the synthesis of saturated and monounsaturated fatty acids, such as 16:0 and 18:1, and to stimulate the activity delta-6 desaturase, decreasing the concentration of linoleic acid. Our results suggest that the observed serum fatty acid composition in subjects with coronary heart disease is dependent on metabolic factors in addition to dietary fatty acid composition.

Identification of different bacterial DNAs in human coronary arteries.

BACKGROUND: Various studies have suggested a link between infection, atherosclerosis and coronary artery disease. We studied whether bacterial DNA is present in coronary specimens obtained from left anterior descending coronary arteries of subjects having sudden deaths of cardiovascular and other causes, as verified by an autopsy. MATERIALS AND METHODS: Coronary specimens were obtained from five subjects who died of sudden coronary causes and five controls. Broad-range 16-s rDNA PCR (Br-PCR) amplification, cloning and sequencing were used to detect bacterial rDNA. RESULTS: Bacterial rDNA sequences of oral pathogens were detected from the coronary samples in all cases regardless of the cause of death. CONCLUSIONS: Br-PCR is a powerful method to detect bacterial rDNA. By this method we were able to detect wide palette of oral bacteria from coronary tissues. Our findings suggest that atheromas may act as mechanical sieves collecting bacteria from the circulation.

Apolipoprotein E and A-IV polymorphisms in ethnic Russians living in Estonia.

137 Russians living in Estonia was screened by isoelectric focusing and immunoblotting procedures to determine the distribution of genetic variations in apolipoprotein E (apoE) and apolipoprotein A-IV (apoA-IV) genes. The apoA-IV-2 allele and epsilon4 allele frequency of the Russians tended to be lower than in most other European populations.

Serum matrix metalloproteinase-9 is elevated in men with a history of myocardial infarction.

Elevated serum inflammatory markers have been reported in coronary heart disease. Levels of serum matrix metalloproteinase-9 (MMP-9), C-reactive protein (CRP), C3-complement (C3) and autoantibodies against oxidized low-density lipoprotein (oxLDL) in 120 male subjects with a history of myocardial infarction (MI) were compared with those in 250 age-matched controls, both groups from a large cross-sectional population survey, the FINRISK study. The concentrations of serum MMP-9 and autoantibodies against oxLDL were measured by enzyme-linked immunosorbent assay, CRP and C3 by immunonephelometry. MMP-9, CRP and C3 concentrations were higher in the subjects with a history of MI than in the controls (p=0.037, p=0.004, and p=0.006, respectively). There was no difference between the groups in serum levels of autoantibodies against oxLDL. In other background characteristics, men in the MI group had higher body mass index (BMI) and serum triglyceride values and lower serum HDL cholesterol values compared to controls (p=0.009, p=0.001, and p<0.001, respectively). When analyzed by stepwise multiple logistic regression using BMI, HDL cholesterol, triglycerides, CRP, C3 and MMP-9 as independent variables, the significant predictors for MI were HDL cholesterol (p=0.002) and MMP-9 (p=0.015). These results suggest that increased serum MMP-9 may reflect inflammatory pathologic processes that are related to progression of atherosclerosis.

A functional variant of the iNOS gene flanking region is associated with LAD coronary artery disease: an autopsy study.

BACKGROUND: Recent studies using reporter gene constructs have indicated significant differences in the promoter activity of inducible nitric oxide synthase (iNOS) gene variants. Although the exact role of iNOS in atherogenesis is unclear, it is possible that this variation site may influence the extent of coronary artery disease (CAD). METHODS: We amplified these (AAAT) repeat variants from the NOS2A gene (denoted iNOS R4 and iNOS R5) from 325 Finnish men included in the Helsinki Sudden Death Study, and studied their association with indices of stenosis and atherosclerosis of the left anterior descending artery (LAD), right coronary artery (RCA) and left circumflex artery (LCX). In order to understand the effect of iNOS genotype on different stages of CAD, our study population was divided into age groups. RESULTS: In the LAD, the progression of atherosclerosis seemed to be more pronounced in the 4/5 genotype carriers than in those with the 4/4 genotype when the different age groups were compared. More specifically, statistically significant differences between the genotypes were found in the subgroup of men aged > 55 years. In this group, men carrying the rare R4/5 genotype presented higher mean values of stenosis percentages (55% vs. 42%, P = 0.008), larger areas of fatty streaks (10.4% vs. 5.9%; P = 0.01) and complicated lesions (3.5% vs. 1.3%; P = 0.001) compared with the R4/4 carriers. No significant association of iNOS genotypes with stenosis and atherosclerosis of RCA and LCX was found. CONCLUSIONS: It appears unlikely the R4/5 genotype plays a major role in the pathogenesis of CAD, as it was not associated with stenosis and atherosclerosis in RCA and LCX. However this genotype may have some role in more pronounced CAD, as seen in the LAD.

Do temporal arteritis lesions contain bacterial DNA?

BACKGROUND: Temporal arteritis is a primary vascular inflammatory disease. The aetiology of temporal arteritis is unknown, but the influence of environmental factors such as infections has been suggested. MATERIALS AND METHODS: We used broad-range PCR, targeting conserved regions of the gene encoding for ribosomal RNA, to detect bacterial DNA in 27 temporal artery biopsies. Five uninvolved temporal arteries were also included. A lung sample of confirmed bacterial pneumonia served as a positive control. Inflammation was examined by histochemistry and light microscopy. RESULTS: The sensitivity of the broad-range PCR assay was 5.0 fg of DNA. Bacterial DNA sequences were neither detected in 27 temporal arteritis specimens nor in the normal temporal artery samples. However, bacterial DNA was successfully amplified from the lung sample of a subject with pneumonia. In addition, human DNA was amplified by primers for human beta-actin from all clinical specimens, suggesting lack of significant inhibitors of the molecular amplification reaction. Histochemistry showed signs of strong inflammation in the arteritis samples. CONCLUSIONS: The lack of detectable amounts of bacterial DNA suggests that viable bacteria do not have a role in chronic stages of temporal arteritis. However, these findings do not rule out the possibility of bacterial degradation products as stimulants of chronic inflammation, or of viable microbes as triggering factors of acute temporal arteritis.

Trends in serum cholesterol and lifestyle indicators in Members of the Finnish Parliament.

OBJECTIVE: To examine the extent that public health promotion activity is reflected in life styles of national decision makers, by analysing trends in coronary heart disease risk factors in Members of the Finnish Parliament (MPs). METHODS: The MPs were studied at the beginning of two subsequent 4-year parliamentary periods between 1991 and 1999. The studies included analyses of serum total cholesterol and high-density lipoprotein (HDL) cholesterol, and a questionnaire about alcohol, smoking and physical activity. RESULTS: Serum total cholesterol was above the national recommendation of 5.0 mmol/l in 85% of the male MPs and 62% of the female MPs. The mean level of serum total cholesterol increased in female MPs during the 4-year follow-up period (P < 0.05), and male MPs showed an increase in mean HDL cholesterol (P < 0.001). The mean body mass index increased in both male (P < 0.01) and female (P < 0.01) MPs during the same period. Alcohol consumption, smoking and physical activity were unchanged during follow-up. CONCLUSIONS: From the public health perspective, serum cholesterol is too high in most MPs, and the level in males is above the national average. Both males and females put on weight during the parliamentary period, and male MPs also showed an increase in HDL cholesterol, which may be explained by other lifestyle factors.

Effect of type of alcoholic beverages on carbohydrate-deficient transferrin, sialic acid, and liver enzymes.

BACKGROUND: There are only limited data obtained under well controlled conditions on the effects of moderate drinking on markers of alcohol use disorders. The aim of this study was to investigate the effects of moderate intake of different alcoholic beverages on these markers, including carbohydrate-deficient transferrin (CDT), sialic acid (SA), and the liver enzymes gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase. METHODS: Eleven apparently healthy, nonsmoking middle-aged men were included in a 12-week randomized, diet-controlled crossover trial according to a 4 x 4 Latin-square design. Changes in CDT, SA, gamma-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase were analyzed after 3 weeks of daily intake of four glasses (40 g of alcohol) of red wine, beer, spirits (Dutch gin), or water (control). RESULTS: After 3 weeks' daily consumption of red wine, a significant decrease of serum CDT concentration was observed compared with water consumption. There was no effect of any alcoholic beverage on the other outcome measures. CONCLUSIONS: Daily consumption of 40 g of alcohol from different types of alcoholic beverages with dinner did not affect SA or liver enzymes. Further investigations to explore the mechanisms for the red wine-induced decreases of CDT, including changes in iron metabolism, are clearly needed.

Serum matrix metalloproteinase-9 concentration in angiographically assessed coronary artery disease.

Expression of several matrix metalloproteinases (MMPs) in atherosclerotic plaques has been well documented, and there are findings to indicate that arterial inflammation is reflected in increased serum concentration of matrix metalloproteinase-9 (MMP-9). In coronary atherosclerosis, there is enhanced expression of this MMP, which may be predictive of the severity of the disease. We determined the concentrations of serum MMP-9 in 61 patients (47 males, 14 females) who had >50% obstruction in one or more coronary arteries as assessed by coronary angiography before bypass surgery. In a control group of 19 patients (9 males, 10 females) there were no pathological findings in coronary angiography. ANOVA showed that serum MMP-9 concentrations were highest in patients with 3-vessel coronary artery disease (CAD) (57.3+/-39.1 microg/L, p=0.011). The difference remained statistically significant after adjustment for age, diabetes and sex (p=0.025, ANCOVA). When the groups were compared with each other, serum MMP-9 concentration was higher in the patients with 3-vessel CAD than in those with 1- or 2-vessel CAD (40.4+/-25.1 microg/L, p=0.044) or in the controls (32.2+/- 16.1 microg/L, p=0.007). These results show that serum MMP-9 is elevated in patients with severe coronary stenosis compared with controls. Since MMP-9 has been suggested to reflect inflammation in atherosclerotic plaques, it may be useful in the evaluation of the severity of cardiovascular disease.

Matrix metalloproteinase-9 is elevated in serum of alcohol abusers.

BACKGROUND: Moderate alcohol consumption has been shown to protect against coronary heart disease. However, excessive alcohol use has been suggested to have detrimental effects on the cardiovascular system. We examined whether there is an association between alcohol abuse and circulating levels of matrix metalloproteinase-9 (MMP-9), which has been linked to unstable coronary heart disease and arterial inflammation. DESIGN: Serum MMP-9 concentrations were compared between 40 male alcoholics (mean age 42 years) with ethanol consumption > 1000 g week(-1) and 40 social drinker males with an ethanol consumption of < 200 g week(-1) (mean age 45 years). RESULTS: The mean serum MMP-9 concentration was significantly higher in sera of alcoholics compared to control subjects (70.9 +/- 47.7 g L(-1) and 43.1 +/- 19.2 g L(-1), respectively; P = 0.001). Within the alcoholic group, MMP-9 concentration did not correlate with age, gamma glutamyl transferase, carbohydrate-deficient transferrin, aspartate aminotransferase, alanine aminotransferase or alkaline phosphatase. CONCLUSION: Our finding of elevated MMP-9 concentrations in sera of chronic alcohol abusers helps understand the mechanisms of cardiovascular risk among these subjects.

Association of serum MMP-9 with autoantibodies against oxidized LDL.

Monocyte-derived macrophages in atherosclerotic plaques secrete matrix metalloproteinases (MMPs), which may contribute to plaque rupture. There has been much speculation as to which factors precipitate in the arterial inflammation. Oxidized low density lipoprotein (oxLDL) has been suggested to have proinflammatory properties, and it has been shown to increase matrix metalloproteinase-9 (MMP-9) secretion by macrophages in vitro. We determined serum MMP-9 concentration and autoantibodies against oxLDL by ELISA in men with angina pectoris (n=243) and age-matched controls (n=238). The association between serum MMP-9 concentration and autoantibodies against oxLDL was evaluated. Autoantibody level against oxLDL, expressed in optical density units, was significantly higher in subjects with angina pectoris compared to controls (0.100+/-0.064 versus 0.088+/-0.051, respectively, P=0.030), but serum levels of MMP-9 did not differ significantly between these groups (54.2+/-29.9 versus 50.6+/-23.1 microg/l). However, autoantibodies against oxLDL correlated positively with serum MMP-9 (r=0.21, P<0.001). In a multiple regression model (including age, diastolic blood pressure, cholesterol, HDL cholesterol, triglycerides, BMI, smoking and MMP-9) serum MMP-9 (beta=0.200, P<0.001) and smoking (beta=0.179, P<0.001) were significantly associated with autoantibodies against oxLDL. In conclusion, autoantibodies against oxLDL were positively associated with angina pectoris and serum MMP-9. Since autoantibody level against oxLDL could be expected to reflect the degree of oxLDL in the vessel wall, our results suggest that oxLDL is associated with MMP-9 in vivo.

Effect of pravastatin in mildly hypercholesterolemic young men on serum matrix metalloproteinases.

Pravastatin decreases serum MMP-9 concentration in clinically healthy men. This may reflect reduction of nonsymptomatic chronic arterial inflammation.