Common promoter variant in cyclooxygenase-2 represses gene expression: evidence of role in acute-phase inflammatory response

Objective: Cyclooxygenase (COX)-2 is a key regulatory enzyme in the synthesis of prostanoids associated with trauma and inflammation. We investigated the COX-2 gene for functional variants that may influence susceptibility to disease. Methods and results: The promoter of COX-2 was screened for variants in healthy subjects by use of polymerase chain reaction-based methods. Promoter activity was investigated by using reporter expression experiments in human lung fibroblasts. Patients undergoing coronary artery bypass graft surgery, with measurements of plasma markers linked to COX-2 activity, were genotyped for association studies. A common COX-2 promoter variant, -765G>C, was found and shown to be carried by >25% of a group of healthy UK subjects. The -765C allele had significantly lower promoter activity compared with -765G, basally (28±3% lower, P<0.005) and in serum-stimulated cells (31±2% lower, P<0.005). In patients subjected to coronary artery bypass graft surgery, the magnitude of rise in levels of C-reactive protein (CRP) was strongly genotype dependent. Compared with -765G homozygotes, patients carrying the -765C allele had significantly lower plasma CRP levels at 1 to 4 days after surgery (14% lower at the peak of CRP levels on day 3, P<0.05 for all time points). Conclusions: For several acute and chronic inflammatory diseases, -765G>C may influence the variability of response observed

Statin therapy and the acute inflammatory response after coronary artery bypass grafting

Preoperative statin therapy has been shown to improve cardiovascular outcome after coronary artery bypass grafting; however, the clinical gain achieved is in excess of the reduction in lipids. We demonstrate that statin therapy exerts a direct anti-inflammatory effect mediated through reduced interleukin-6 production

The effect of fibrinogen genotype on fibrinogen levels after strenuous physical exercise

We have examined the effect of two beta-fibrinogen gene promoter polymorphisms (-455G&gt;A and -854G&gt;A) on the Fibrinogen response to severe exercise in a croup of male army recruits undergoing basic training. Fibrinogen was measured pre-training and again serially after severe 48 h final military exercise (FME). Out of 884 subjects, 762 completed training of whom 250 were selected for post-FME study. Fibrinogen levels (g/l) were significantly elevated over baseline levels 2, 48 and 96 h after FME, representing increases of 15.7%, 3.4% and 7.6% (p lt 0.005; p = 0.05 and p lt 0.005 respectively), with higher levels in -455A allele carriers than genotype -455GG: 3.17 +/- 0.05 vs. 2.94 +/- 0.05 (p lt 0.001), 2.86 +/- 0.05 vs. 2.60 +/- 0.05 (p lt 0.0005) and 2.98 +/- 0.06 vs. 2.69 +/- 0.06 (p lt 0.0005) at 2, 48 and 96 h respectively. There was no effect of the -854G&gt;A polymorphism on fibrinogen, even after taking, into account beta-fibrinogen -455 genotype. Thus the fibrinogen -455G&gt;A polymorphism influences fibrinogen levels following exercise. The effect of genotype might be clinically relevant at times of hyperfibrinogenaemia such as following an acute inflammatory response

Interleukin-6 gene -174G gt C and -572G gt C promoter polymorphisms are strong predictors of plasma - Interleukin-6 levels after coronary artery bypass surgery

Interleukin-6 (IL-6) synthesized in response to diverse stimuli may play an important role in bridging the inflammatory and atherosclerotic processes. The acute-phase response after coronary artery bypass graft surgery (CABG) is associated with the induction and release of cytokines, such as IL-6. We have examined the effect of common polymorphisms in the IL-6 gene promoter (-1746 gt C, -572G gt C, and -5976 gt A) on IL-6 levels after elective CABG. DNA extracted from the peripheral blood of 127 patients was amplified by polymerase chain reaction. IL-6 genotypes were resolved by gel electrophoresis after restriction enzyme digestion. Serum IL-6 was measured before surgery and in serial samples at 6, 24, 48, and 72 hours after CABG. Genotype distribution was as expected for a population in Hardy-Weinberg equilibrium for all polymorphisms. Rare allele frequencies (+/-95% CIs) were similar to those reported previously: -597A 0.36 (0.30 to 0.42), -572C 0.07 (0.04 to 0.10), and -1740 0.37 (0.31 to 0.43). The -1746 gt C and -5976 gt A genotypes were in strong allelic association (Delta =0.97, P lt 0.001). Baseline IL-6 levels did not significantly differ between patients with different genotypes for any polymorphism. However, 6 hours after CABG, peak IL-6 levels were significantly higher (P=0.03) in carriers of the -572C allele than in those of the -572GG genotype (355 +/- 67 versus 216 +/- 13 pg/mL, respectively) and in those with genotype -174CC compared with -174G allele carriers (287 +/- 31 versus 227 +/- 15 pg/mL, respectively; P=0.04). These effects remained statistically significant after adjusting for possible confounders, including age, sex, smoking, duration of cardiopulmonary bypass, aortic cross-clamp time, and total duration of surgery. These data demonstrate that IL-6 promoter polymorphisms influence peak IL-6 production after CABG, suggesting that these polymorphisms, which are functional in vitro, are also functional in vivo, suggesting a genetic influence on IL-6 levels after acute severe injury

Human CRP gene polymorphism influences CRP levels - implications for the prediction and pathogenesis of coronary heart disease

Objective - C- reactive protein ( CRP) concentrations are predictive of cardiovascular disease, and levels are heritable, in part. We identified novel polymorphisms in the CRP gene and assessed their influence on CRP level. Methods and Results - CRP was measured in 250 male army recruits before and after strenuous exercise and perioperatively in 193 coronary artery bypass graft ( CABG) patients. Two novel polymorphisms were identified in the CRP gene, - 717G gt A in the promoter and + 1444C gt T in the 3' UTR. Among army recruits, CRP was higher in + 1444TT homozygotes than + 1444 C- allele carriers at baseline ( 1.04 +/- 0.38 versus 0.55 +/- 0.06, P = 0.014) and at all time points after exercise ( 2.35 +/- 0.68 versus 1.07 +/- 0.12, 2.11 +/- 0.53 versus 0.88 +/- 0.09, and 1.77 -/+ 0.44 versus 0.71 -/+ 0.09, P = 0.034, P = 0.007, and P = 0.013, at 2, 48, and 96 hours after exercise, respectively). In the CABG patients, mean CRP ( mg/ L) rose from 1.97 -/+ 0.36 at baseline to 167.2 +/- 5.0 72 hours postoperatively. Genotype did not influence CRP at baseline; however, peak post- CABG CRP levels were higher in + 1444TT homozygotes compared with + 1444C- allele carriers ( 198 +/- 17 versus 164 +/- 5, P = 0.03). Conclusions - The CRP gene + 1444C gt T variant influences basal and stimulated CRP level. These findings have implications both for the prediction and pathogenesis of coronary heart disease

Effect of a COL1A1 Sp1 Binding Site Polymorphism on Arterial Pulse Wave Velocity: An Index of Compliance.

-Reduced arterial compliance precedes changes in blood pressure, which may be mediated through alterations in vessel wall matrix composition. We investigated the effect of the collagen type I-alpha1 gene (COL1A1) +2046G>T polymorphism on arterial compliance in healthy individuals. We recruited 489 subjects (251 men and 238 women; mean age, 22.6+/-1.6 years). COL1A1 genotypes were determined using polymerase chain reaction and digestion by restriction enzyme Bal1. Arterial pulse wave velocities were measured in 3 segments, aortoiliac (PWVA), aortoradial (PWVB), and aorto-dorsalis-pedis (PWVF), as an index of compliance using a noninvasive optical method. Data were available for 455 subjects. The sample was in Hardy-Weinberg equilibrium with genotype distributions and allele frequencies that were not significantly different from those reported previously. The T allele frequency was 0.22 (95% confidence interval, 0.19 to 0.24). Two hundred eighty-three (62.2%) subjects were genotype GG, 148 (35.5%) subjects were genotype GT, and 24 (5.3%) subjects were genotype TT. A comparison of GG homozygotes with GT and TT individuals demonstrated a statistically significant association with arterial compliance: PWVF 4.92+/-0.03 versus 5.06+/-0.05 m/s (ANOVA, P=0.009), PWVB 4.20+/-0.03 versus 4.32+/-0.04 m/s (ANOVA, P=0.036), and PWVA 3.07+/-0.03 versus 3.15+/-0.03 m/s (ANOVA, P=0.045). The effects of genotype were independent of age, gender, smoking, mean arterial pressure, body mass index, family history of hypertension, and activity scores. We report an association between the COL1A1 gene polymorphism and arterial compliance. Alterations in arterial collagen type 1A deposition may play a role in the regulation of arterial compliance