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Increased local immune and inflammatory responses in obese individuals with periodontitis may explain the aggressive clinical presentation and altered treatment response when compared to that of normal weight subjects. Our goal was to identify any differences in microRNA (miRNA) expression profiles of gingival tissue in periodontitis when obesity is present, which may suggest novel molecular pathways that this miRNA network may affect. Total RNA was extracted from gingival tissue biopsies collected from normal weight and obese individuals with periodontitis; miRNA expression profiling was performed with Affymetrix GeneChip miRNA 3.0 arrays; and results were validated with quantitative reverse transcription polymerase chain reaction (qRT-PCR). In silico identification of previously confirmed miRNA gene targets was conducted through miRTarBase and miRWalk databases, and pathway enrichment analysis identified enriched miRNA gene sets. Expression of selected genes in the same biopsy samples was tested with qRT-PCR. The gingival tissue miRNA profile of obese patients, compared to that of normal weight patients, showed 13 upregulated and 22 downregulated miRNAs, among which miR-200b was validated by qRT-PCR to be significantly increased in obesity. Functional analysis of 51 experimentally validated miR-200b gene targets identified enrichment of genes involved in cell motility, differentiation, DNA binding, response to stimulus, and vasculature development pathways not previously identified in the obesity-specific disease profile. Furthermore, the expression of the miR-200b gene targets ZEB1/2, GATA2, and KDR was confirmed by qRT-PCR as being lower in obese patients with periodontitis versus normal weight patients, suggesting a role of miR-200b in regulation of a set of gene targets and biological pathways relevant to wound healing and angiogenesis. Functional studies to explore the role of miR-200b in the above processes may offer new insights on putative therapeutic targets for this group of patients. [ABSTRACT FROM PUBLISHER]

Single nucleotide polymorphisms within the promoter of the interleukin6 (IL-6) gene (-597G>A, -572G>C and -174G>C) have previously been associated with increased risk of coronary heart disease, as well as influencing transcription of IL-6 both in vitro and in vivo. In addition to these, a polymorphic AnTn tract is also present in the IL-6 promoter. Analysis in five different primate species showed a G allele at all three SNP sites in all species. By contrast, the AnTn tract was polymorphic in at least three species, and was roughly conserved in overall length despite an increase in the relative proportion of A versus T in the evolution of the human sequence from that in the ancestor of the great apes. The effect of the AnTn tract on IL-6 levels was examined in 132 patients undergoing coronary artery bypass graft surgery, a known inflammatory stimulus for IL-6 production. Four alleles were identified: AST12 (frequency 0.35), A9T11 (0.26), A10T11 (0.21) and A10T10 (0.18). Isolating the effect of individual alleles on an identical haplotypic background for the other promoter SNP's showed that A9T11 homozygous individuals had significantly higher post-operative IL-6 levels than A10T11 homozygotes. The A8T12 allele could not be analysed separately due to strong association with -174C. The conserved length of the AnTn tract and association with IL-6 levels in vivo strongly suggest the tract has a functional role on IL-6 expression, independent of other polymorphisms in the promoter. [ABSTRACT FROM AUTHOR]

Abstract: The increasing prevalence of obesity and metabolic syndrome/insulin resistance has attracted considerable interest due to their identification as risk factors for cardiovascular disease and, hence, targets for cardiovascular disease prevention. This review focuses on adiponectin, the most profusely secreted protein from adipose tissue, which itself is being increasingly recognised as an important and very active endocrine organ, secreting a wide range of biologically active substances known as adipokines or adipocytokines. Adiponectin has been demonstrated to have insulin sensitising effects, and secretion of adiponectin is reduced as adipose tissue mass increases. Adiponectin has also been demonstrated to have anti-inflammatory and anti-atherogenic properties, and is independently associated with cardiovascular disease. The evidence that suggests adiponectin plays a role in the relationship between obesity and insulin resistance, and also insulin resistance and cardiovascular disease, is examined. Variation in the adiponectin gene is one tool to determine whether this relationship is causal. The association of identified variants with human disease, specifically obesity and its consequences, type 2 diabetes and cardiovascular disease is reviewed. This data may enable patients at greater risk of the adverse effects of obesity to be identified and, as such, benefit from more targeted therapy of its consequences. [Copyright &y& Elsevier]

Background: Hyperlipidaemia is a major risk factor for cardiovascular disease, and atherosclerosis is the underlying cause of both myocardial infarction and stroke. We have previously shown that the Pro251 variant of perilipin-2 reduces plasma triglycerides and may therefore be beneficial to reduce atherosclerosis development.Objective: We sought to delineate putative beneficial effects of the Pro251 variant of perlipin-2 on subclinical atherosclerosis and the mechanism by which it acts.Methods: A pan-European cohort of high-risk individuals where carotid intima-media thickness has been assessed was adopted. Human primary monocyte-derived macrophages were prepared from whole blood from individuals recruited by perilipin-2 genotype or from buffy coats from the Karolinska University hospital blood central.Results: The Pro251 variant of perilipin-2 is associated with decreased intima-media thickness at baseline and over 30 months of follow-up. Using human primary monocyte-derived macrophages from carriers of the beneficial Pro251 variant, we show that this variant increases autophagy activity, cholesterol efflux and a controlled inflammatory response. Through extensive mechanistic studies, we demonstrate that increase in autophagy activity is accompanied with an increase in liver-X-receptor (LXR) activity and that LXR and autophagy reciprocally activate each other in a feed-forward loop, regulated by CYP27A1 and 27OH-cholesterol.Conclusions: For the first time, we show that perilipin-2 affects susceptibility to human atherosclerosis through activation of autophagy and stimulation of cholesterol efflux. We demonstrate that perilipin-2 modulates levels of the LXR ligand 27OH-cholesterol and initiates a feed-forward loop where LXR and autophagy reciprocally activate each other; the mechanism by which perilipin-2 exerts its beneficial effects on subclinical atherosclerosis. [ABSTRACT FROM AUTHOR]

Background Cardiovascular disease is a leading cause of mortality in Indian population. Mutations in LDLR , APOB and PCSK9 genes may lead to Familial Hypercholesterolemia, an autosomal dominant disorder which in turn leads to cardiovascular diseases. The primary objective of this study is to analyze these genes in CAD patients of Indian population. Methods A total of 30 patients were selected out of 300 CAD patients based on UK-Simon Broome criteria from South India. The gDNA was isolated by organic extraction method and the exons and exon-intron boundaries of LDLR gene, APOB (exon 26) and PCSK9 (exon 7) were screened by PCR-high resolution melt analysis. The amplicons showing shift in melting pattern were sequenced to find out the variation. Results This study reports three novel variations, an intronic deletion c.694 + 8_694 + 18del in intron 4, a synonymous variation c.966 C > T [p. (N322 =)] in exon 7 and a deletion insertion c.1399_1340delinsTA [p. (T467Y)] in exon 10, two recurrent variations c.862G > A [p. (E288K)] in exon 6 and a splice site variation c.1845 + 2T > C in exon–intron junction of exon 12 in LDLR gene and PCSK9 gene had c.1180 + 17C > T change in intron 7. However there are no pathogenic variations in APOB and PCSK9 genes in Indian population. In silico analysis predicted all the variations as pathogenic except the synonymous variation. Conclusion This report adds five new variations to the spectrum of LDLR variations in Indian population. This study also suggests that UK Simon Broom criteria can be followed to categorize FH patients in Indian population. [ABSTRACT FROM AUTHOR]

A previous report suggested that 88% of individuals in the general population with total cholesterol (TC) > 9.3 mmol/L have familial hypercholesterolaemia (FH). We tested this hypothesis in a cohort of 4896 UK civil servants, mean (SD) age 44 (±6) years, using next generation sequencing to achieve a comprehensive genetic diagnosis. 25 (0.5%) participants (mean age 49.2 years) had baseline TC > 9.3 mmol/L, and overall we found an FH-causing mutation in the LDLR gene in seven (28%) subjects. The detection rate increased to 39% by excluding eight participants with triglyceride levels over 2.3 mmol/L, and reached 75% in those with TC > 10.4 mmol/L. By extrapolation, the detection rate would be ∼25% by including all participants with TC > 8.6 mmol/L (2.5 standard deviations from the mean). Based on the 1/500 FH frequency, 30% of all FH-cases in this cohort would be missed using the 9.3 mmol/L cut-off. Given that an overall detection rate of 25% is considered economically acceptable, these data suggest that a diagnostic TC cut-off of 8.6 mmol/L, rather than 9.3 mmol/L would be clinically useful for FH in the general population. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Serum LDL conjugated diene concentration is a marker of oxidative modification of LDL. We investigated the relationship between LDL conjugated dienes and cross-sectional subclinical atherosclerosis assessed by carotid IMT in high-risk subjects of a multicenter study. Methods: Serum LDL conjugated dienes and ultrasonographically assessed carotid intima–media thickness (IMTmean, IMTmax and IMTmean-max) were available for 553 subjects from Finland, France, Italy, the Netherlands, and Sweden. Results: In multivariate regression analysis, gender (p < 0.001), age (p < 0.001), systolic blood pressure (IMTmean, p = 0.01; IMTmean-max, p = 0.05) and serum LDL conjugated dienes (p = 0.02 for both IMTmean and IMTmean-max) were the strongest determinants of IMT variation, adjusted for study center, ultrasound videotape reader and serum LDL cholesterol. Pack-years of smoking, added into the regression model, did not destroy the significant association between increased serum LDL conjugated dienes and IMT. Ratio of LDL conjugated dienes to LDL particle cholesterol was higher in subjects of Northern recruiting centers than of Southern centers (r = 0.39, p < 0.0001). Conclusions: There was a cross-sectional association between in vivo increased LDL oxidative modification and subclinical atherosclerosis after adjustment for traditional risk factors. The subjects in Northern countries of Europe had more oxidatively modified lipids per cholesterol in LDL particle than subjects in Southern countries. [Copyright &y& Elsevier]

Abstract: Mitochondrial superoxide dismutase 2 (SOD2) is an endogenous anti-oxidant enzyme. The rs4880 gene variant results in a C>T substitution, influencing SOD enzymatic activity. This variant has been associated with micro- and macro-vascular complications in diabetes mellitus. Our aim was to examine the association between this variant and coronary heart disease (CHD) risk in a cross-sectional sample of subjects with diabetes. 776 Caucasian subjects with diabetes were genotyped. CHD risk, oxidised-LDL and plasma total anti-oxidant status (TAOS) were analysed in relation to genotype. In females, the TT genotype was associated with CHD (CC/CT/TT: No CHD vs. CHD: 22.4/56.0/21.6% vs. 12.0/50.0/38.0%, p =0.03; for CC/CT vs. TT, p =0.01). The odds ratio for CHD associated with the TT genotype compared to CC/CT was 2.22 [95%CI: 1.17–4.24], p =0.01. The TT genotype was also associated with significantly lower plasma TAOS. In males, no association was observed between genotype and CHD risk, but CHD was significantly associated with age, lower HDL, higher triglycerides, higher BMI and cigarette smoking. The TT genotype of this variant is associated with increased CHD risk and lower plasma anti-oxidant defences in females with diabetes. This modest genotype-effect is not apparent in males where traditional risk factors may play a greater role. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To examine all-cause and cardiovascular mortality in patients with severe hypertriglyceridaemia. Methods: 337 patients aged less than 80 years (47 with diabetes, 75 women) with a fasting triglyceride concentration on at least two occasions of >5.0mmol/l were registered by 21 lipid clinics in the United Kingdom and followed prospectively between 1980 and 2008 for 4353 person-years. The standardised mortality ratio (SMR) was calculated by comparison with the general population. Results: The mean untreated total cholesterol concentration was 9.8 (SD 3.6)mmol/l for men and 11.9 (7.2)mmol/l for women and the corresponding geometric mean triglyceride concentration was 12.6 (inter-quartile range 7.3, 21.6) and 15.7 (8.2, 29.2)mmol/l. There were 70 deaths, including 35 from CHD and 7 from stroke. The SMR for CHD was raised at 327 (95% confidence intervals 228, 455; p <0.0001) and remained elevated after excluding patients with diabetes at registration (SMR=287, 95% CI 190, 419; p <0.0001), and after excluding patients with CHD at registration (SMR=259, 95% CI 158, 400; p =0.0003). The increased SMR was most marked in younger men aged 40–59 years (SMR=544, 95% CI 304, 897; p <0.0001). The SMR for stroke for patients aged 20–79 years was raised at 262 (95% CI 105, 540; p =0.04), as was all-cause mortality at 164 (95% CI 129, 208; p <0.001). Conclusion: Severe hypertriglyceridaemia is associated with a substantially increased mortality from cardiovascular disease, even in the absence of diabetes. In addition to lowering triglyceride concentrations to reduce the risk of pancreatitis, treatment should aim to reduce the overall cardiovascular risk. [ABSTRACT FROM AUTHOR]

Abstract: Aims: Our aim was to test the association of mean leukocyte telomere length (LTL) with ultrasonic measures of subclinical atherosclerosis such as intima-media thickness in the common carotid (IMTcc) and sum of plaque areas (SPA) and with serological markers. Methods and results: Carotid and femoral bifurcations were scanned in 762 general population volunteers (46% men) over 40. Four features were considered: (a) IMTcc, (b) sum plaque areas of carotid plaques (SPAcar), (c) sum plaque area of common femoral plaques (SPAfem) and (d) sum plaque area (SPA – sum of the plaque areas of the largest plaques present in each of both carotid and femoral bifurcations). Mean LTL was determined with a quantitative real-time PCR-based method. IMTcc was strongly associated with mean LTL both before and after correction for traditional risk factors (B= −0.002; 95% CI=−0.004 to −0.00; p =0.014). In sex-specific analysis, the association was stronger in men (p for sex interaction<0.001). SPAfem was associated with LTL in women before and after correction (B=−0.195; 95% CI=−0.38 to −0.01; p =0.037) (p for sex interaction<0.001). LTL was also associated with age and sex-adjusted levels of hsCRP (p =0.012), sCD40L (p =0.042), homocysteine (p =0.006), creatinine (p =0.02), ApoA1 (p =0.01), Lp(a) (p =0.04) and HOMA-IR (p =0.008). Conclusions: Our results support the telomere hypothesis and highlight potential differences in the biological mechanisms leading to intima-media thickening and/or plaque formation between vascular beds. They may provide insights into a novel treatment of antisenescence to prevent atherosclerosis. [Copyright &y& Elsevier]

Abstract: We recently reported an association between interleukin-6 (IL6) polymorphisms (SNPs) and haplotypes and aggressive periodontitis (AgP). The aim of this study was to investigate this association in a larger cohort of subjects, affected by either aggressive or chronic periodontitis. Five IL6 SNPs were analyzed in 765 subjects (167 generalized aggressive periodontitis, 57 localized aggressive, 310 chronic periodontitis and 231 periodontally healthy). Among Caucasians (n =454) there were moderate associations for −1363T allele (p =0.011) and for −174GG and −1363GG genotypes with diagnosis of periodontitis (respectively, p =0.044, OR=1.6, 95% CI=1.0–2.4, and p =0.017, OR=1.8, 95% CI=1.1–2.8, adjusted for age, gender and smoking). Haplotypes containing the −174G>C, −1363G>T and −1480C>G polymorphisms were associated with diagnosis of periodontitis (p =0.02). Subgroup analysis by disease phenotype showed associations for the localized AgP (LAgP) group and −1480C>G and −6106A>T SNPs (p =0.007 and 0.010, respectively). Among Caucasians the genotypes IL6 −1480 CC and −6106 TT increased the adjusted OR for LAgP (OR=3.09 and 2.27, respectively). This study supports the hypothesis that IL6 polymorphisms and haplotypes are moderately associated with periodontitis, possibly acting through influencing tissue levels of IL6. This association is stronger for LAgP than for other periodontal disease phenotypes. [Copyright &y& Elsevier]

Abstract: Interleukin-6 (IL6) is an important pleiotropic cytokine that is regulated at the transcriptional level. To date, most work on its regulation has focused on a 1.2kb region 5′ from the start of transcription, similar to published reports on other cytokine genes. This report demonstrates for the first time that a cytokine gene can be regulated by cis-acting regions much further upstream than previously examined. Comparative genomic analysis showed that a 120kb region contains blocks of sequence conservation between human and rodent genomes, and that a 15kb region proximal to the start of transcription contains 10 highly homologous sequence blocks of between 100 and 250bp. By means of a reporter gene assay, a novel transcriptionally active region located between −5307 and −5202bp upstream from the start of transcription was identified. Electrophoretic mobility shift assays showed nuclear protein(s) binding to this region, thus raising the possibility that the regulatory activity shown by the reporter gene constructs may be mediated by these proteins. These results suggest that the regulation of IL6 expression involves a much larger upstream region than previously examined and the control of IL6 transcription is likely to be regulated by a complex mechanism of modular cis-regulatory elements. [Copyright &y& Elsevier]

Abstract: Lipoprotein associated phospholipase A2 (Lp-PLA2) modulates low-density lipoprotein (LDL) oxidation by hydrolysing oxidised phospholipids present on particle surfaces. We investigated whether Lp-PLA2 activity and PLA2G7 A379V genotype were related to mediators of atherosclerosis in a diabetic study. Plasma Lp-PLA2 activity (taken in men only) and A379V genotype were investigated with regards to metabolic syndrome (MS), UKPDS risk score, and oxidised LDL (oxLDL/LDL), in a cohort of Caucasian men and women (n =783, age 62.5±13.7 years). After adjustment for type of diabetes, CHD status, and statin use, those individuals with features defining the MS (WHO guidelines) had higher Lp-PLA2 activity (35.6±11.9nmol/min/ml) compared to those without (33.0±10.8nmol/min/ml) (p =0.02). Quartiles of UKPDS coronary heart disease (CHD) risk score were also positively associated with Lp-PLA2 activity (p =0.006, p =0.004 linear trend). Those men in the highest quartile of oxLDL/LDL level had the lowest Lp-PLA2 activity (31.3±10.5nmol/min/ml) when compared to the middle two (32.3±9.8 and 35.9±10.9nmol/min/ml, respectively) and lowest quartile (35.6 ±12.5nmol/min/ml; p =0.03, p =0.004 linear trend). There was no significant association between A379V genotype and Lp-PLA2 enzyme activity (p =0.34) or oxLDL/LDL (p =0.32). Lp-PLA2 activity is an independent predictor of CHD risk and MS in a sample of subjects with diabetes mellitus. The association of Lp-PLA2 activity with oxLDL/LDL suggests that Lp-PLA2 may be a modulating factor in the process of atherosclerosis. [Copyright &y& Elsevier]

Abstract: We have progressively analysed three studies of coronary heart disease (CHD) for a variant in EPCR (Ser219Gly). Initially, in a prospective study, NPHSII, while no overall CHD-risk was identified in heterozygotes, homozygotes for 219Gly exhibited a three-fold elevated risk (HR 3.3, CI 1.22–8.96). In diabetics within NPHSII, there was a suggestion that 219Gly+ was associated with elevated CHD-risk (HR 1.89, CI 0.39–9.06) although numbers were small. To further assess the effect of the variant in diabetes, a case–control study of MI, HIFMECH, was used, in which previous analysis had defined a group with metabolic syndrome, by factor analysis. A significant CHD-risk interaction was identified between genotype and the ‘metabolic syndrome’ factor (interaction p =0.009). To further assess CHD-risk for this variant in type-2 diabetes and to assess the effect of the variant upon thrombin generation and plasma levels of soluble EPCR, a cross-sectional study of type-2 diabetes was used. A significant CHD-risk was identified for European Whites (OR 2.84, CI 1.38–5.85) and Indian Asians in this study (OR 1.6, CI 1.00–2.57) and the frequency of 219Gly was two-fold higher in Indian Asians. Soluble EPCR levels were strongly associated with genotype, with homozygotes for 219Gly having four-fold higher levels (p <0.0001). In vitro studies of EPCR-transfected cells suggested increased basal release of sEPCR from cells expressing the 219Gly EPCR phenotype. Furthermore, in base-line samples from NPHSII and in the diabetic study, a significant increase in prothrombin F1+2 level was observed for 219Gly. The increased CHD-risk and thrombin generation appears to be acting through increased shedding of the Gly allele from the cell surface. [Copyright &y& Elsevier]

Abstract: Experimental and clinical observations suggest that innate immunity plays a major role in the pathogenesis and progression of atherosclerosis. A common C-260T polymorphism in the promoter of the CD14 gene, the trans-membrane receptor of lipopolysaccharides, has been inconsistently associated with coronary heart disease. Our objective was to evaluate the contribution of the CD14 polymorphism to the inflammatory response and to the risk of myocardial infarction (MI). We used an European case-control study, the HIFMECH study, comparing 533 men with MI and 575 sex- and age-matched controls. Associations between genotype and disease outcome, according to interleukin-6 (IL-6) and C-reactive protein (CRP) levels, were assessed using conditional logistic regression. The CD14/C-260T polymorphism was associated with plasma IL-6 levels, T/T subjects having higher plasma levels than C/C in cases but not in controls (mean±S.D.: 2.04±1.37 versus 1.70±1.15, p =0.01; 1.20±0.75 versus 1.35±0.88, p =0.31, respectively). Overall, the CD14/C-260T polymorphism was not associated with the risk of MI. However, in individuals with IL-6 plasma levels in the highest tertile, T allele carriers had a higher risk of MI than C/C (OR: 1.85; CI 95 1.05–3.25). IL-6 increased the risk of MI in carriers of the T allele (OR for first versus third IL-6 tertile: 4.02; CI 95 2.24–7.21), but not in C/C (OR: 0.75; CI 95 0.32–1.74, p =0.004 for interaction). The data indicate a role for CD14/C-260T in MI. The risk mediated by the polymorphism is highly dependent on IL-6 plasma levels. [Copyright &y& Elsevier]

Abstract: Background:: The prognosis from coronary heart disease (CHD) for patients with heterozygous familial hypercholesterolaemia has improved substantially since the introduction of HMG Co-A reductase inhibitors (statins), but the effect of lipid-lowering drug therapy combined with dietary and life style advice on non-coronary mortality and the risk of fatal cancer is unclear. Methods:: The cohort of 2871 patients was recruited from 21 outpatient lipid clinics in the UK from 1980 to 1998 and was followed for 22,992 person-years. The standardised mortality ratio (SMR) was calculated from the ratio of the number of deaths observed to the number expected in the general population of England and Wales. Results:: There were 169 deaths, including 102 (60.4%) from CHD, and 32 (18.9%) from cancer. The SMR for CHD was 2.5-fold higher than in the general population (95% CI 2.1, 3.1), but the all-cause SMR was not increased (1.1, 95% CI 0.9, 1.3) and non-coronary mortality was significantly lower in men (0.5, 95% CI 0.3, 0.7) and women (0.6, 95% CI 0.4, 0.9). The SMR for all cancers was significantly reduced (0.6, 95% CI 0.4, 0.8) with an 80% reduction in fatal cancers of the respiratory and intra-thoracic organs and a non-significant reduction in fatal cancers of the genitourinary and digestive organs. Conclusions:: Although the study cannot exclude the possibility that statins have anti-cancer activity, the results strongly suggest that giving advice to consume a healthy diet, increase physical activity and stop smoking is associated with a substantial reduction in mortality from cancer. [Copyright &y& Elsevier]