The role of C-reactive protein polymorphisms in inflammation and cardiovascular risk

Meta-analysis of the association between dietary inflammation index and C-reactive protein level

BACKGROUND

There have been various clinical studies on the effect of dietary inflammatory index (DII) on circulating inflammatory biomarkers, but the findings from these are contradictory. The aim of the present study was to clarify any association.

METHODS

The PubMed, Embase, Web of Science and Cochrane Library database were searched for relevant studies from inception February 2021. There were no language restrictions. Two investigators independently selected eligible studies. Measures of association were pooled by using an inverse-variance weighted random-effects model. The heterogeneity among studies was examined using the I2 index. Publication bias, sensitivity and subgroup analyses were also performed.

RESULTS

A total of 13 cross-sectional studies were identified, involving 54,813 participants. The adjusted pooled OR of C-reactive protein (CRP) levels for the highest (the most pro-inflammatory diet) versus lowest (the most anti-inflammatory diet) DII categories was 1.25 (95% CI: 1.18-1.32; I2  = 59.4%, P = .002). Subgroup analyses suggested the main source of study heterogeneity was the geographic area (Asia, Europe, or USA) and CRP levels (>3 mg/L or others). This finding was remarkably robust in the sensitivity analysis.

CONCLUSION

The meta-analysis suggests that more pro-inflammatory DII scores were positively associated with CRP, the DII scores can be useful to assess the diet inflammatory properties and its association with low-grade inflammation.

Psychiatric symptoms are not associated with circulating CRP concentrations after controlling for medical, social, and demographic factors

Elevated serum concentrations (>3 mg/L) of the acute-phase protein, C-reactive protein (CRP), is used as a clinical marker of inflammation and is reported to be a strong risk factor for cardiovascular disease. In psychiatric populations, CRP concentration is reported to be higher in depressed versus healthy individuals. Positive associations between CRP and depression have been established in both clinical and community samples, but effect sizes are attenuated after controlling for confounding variables. Similarly, emerging research has begun to draw a link between inflammation, symptoms of anxiety, and substance abuse. Given the high level of comorbid anxiety and substance use disorders in many depressed populations, this study examined whether depression (Patient Health Questionnaire 9 [PHQ-9]) and substance use-related (Drug Abuse Screening Test [DAST]) symptoms were associated with CRP concentrations in the blood after adjusting for relevant medical, social, and demographic covariates in a large sample undergoing screening for several transdiagnostic psychiatric research studies. A total of 1,724 participants were analyzed for association of CRP with variables using multivariate linear regression. An unadjusted model with no covariates showed that PHQ-9 was significantly associated with CRP in All (β = 0.125), Female (β = 0.091), and Male (β = 0.154) participants, but DAST was significantly associated with CRP in males only (β = 0.120). For the adjusted model, in both males and females, mood-stabilizer treatment (β = 0.630), opioid medication (β = 0.360), body mass index (β = 0.244), percent body fat (β = 0.289), nicotine use (β = 0.063), and self-reported sleep disturbance (β = 0.061) were significantly associated with increased CRP concentrations. In females, oral contraceptive use (β = 0.576), and waist-to-hip ratio (β = 0.086), and in males, non-steroidal anti-inflammatory drug use (β = 0.367) were also associated with increased CRP concentrations. There was no significant association between CRP and individual depressive, anxiety, or substance use-related symptoms when covariates were included in the regression models. These results suggest that associations between circulating CRP and the severity of psychiatric symptoms are dependent on the type of covariates controlled for in statistical analyses.

Roles of C-reactive protein polymorphisms and life event changes on cognitive function in bipolar patients receiving valproate

Introduction

Patients with bipolar disorder (BD) exhibit an inflamed condition that is associated with metabolic disturbance and cognitive impairment. Whether inflammation, represented by C-reactive protein (CRP), is causally associated with BD and influences treatment outcome has not been established.

Methods

We examined whether CRP is a causal factor for the risk of BD in drug-naïve, depressed BD patients and investigated whether polymorphisms in CRP and life event changes influence cognitive function in BD patients receiving valproate (VPA) treatment.

Results

Our results showed that BD patients had significantly higher CRP levels and worse cognitive function than the controls, while the frequencies of CRP single nucleotide polymorphisms in BD patients and in controls were not different. In addition, the life event scale score was higher for BD patients than for controls. Furthermore, the genotypes of CRP polymorphisms and the interactions between polymorphisms of CRP and life event scale score had a significant influence on cognitive performance in BD patients after 12 weeks of VPA treatment.

Conclusion

Our study demonstrated the clinical utility of the application of functional genetics in clarifying the interactions among CRP, life event stress, and BD and suggested the important roles of CRP gene–environment interactions in developing treatment strategies for BD.

Admission C-reactive protein concentrations are associated with unfavourable neurological outcome after out-of-hospital cardiac arrest

Whether admission C-reactive protein (aCRP) concentrations are associated with neurological outcome after out-of-hospital cardiac arrest (OHCA) is controversial. Based on established kinetics of CRP, we hypothesized that aCRP may reflect the pre-arrest state of health and investigated associations with neurological outcome. Prospectively collected data from the Vienna Clinical Cardiac Arrest Registry of the Department of Emergency Medicine were analysed. Adults (≥ 18 years) who suffered a non-traumatic OHCA between January 2013 and December 2018 with return of spontaneous circulation, but without extracorporeal cardiopulmonary resuscitation therapy were eligible. The primary endpoint was a composite of unfavourable neurologic function or death (defined as Cerebral Performance Category 3–5) at 30 days. Associations of CRP levels drawn within 30 min of hospital admission were assessed using binary logistic regression. ACRP concentrations were overall low in our population (n = 832), but higher in the unfavourable outcome group [median: 0.44 (quartiles 0.15–1.44) mg/dL vs. 0.26 (0.11–0.62) mg/dL, p < 0.001]. The crude odds ratio for higher aCRP concentrations was 1.19 (95% CI 1.10–1.28, p < 0.001, per mg/dL) to have unfavourable neurological outcome. After multivariate adjustment for traditional prognostication markers the odds ratio of higher aCRP concentrations was 1.13 (95% CI 1.04–1.22, p = 0.002). Sensitivity of aCRP was low, but specificity for unfavourable neurological outcome was 90% for the cut-off at 1.5 mg/dL and 97.5% for 5 mg/dL CRP. In conclusion, high aCRP levels are associated with unfavourable neurological outcome at day 30 after OHCA.

Meta-Analysis on the Association of C-Reactive Protein Polymorphisms with Metabolic Syndrome

Polymorphisms in the C-reactive protein (CRP) genes might have crucial role in the development of metabolic syndrome (MetS). In the current comprehensive meta-analyses, we aim to provide a quantitative assessment of the association between CRP single-nucleotide polymorphisms (SNPs) and the risk of MetS. An electronic search was performed on several databases. After data extraction, random effect model was used to calculate the pooled odds ratio (OR) and 95% confidence intervals (CIs). Four independent studies including case–control, cohort, and cross-sectional methods were analyzed. Our meta-analysis indicated that CRP polymorphisms are not significantly associated with MetS (OR = 0.92, 95% CI = 0.77–1.10) with significant heterogeneity ( I²  = 55.4%; p -value = 0.008). The subgroup analysis revealed that only GG has significant association with MetS (OR = 0.32, 95% CI = 0.13–0.80, p -value = 0.015) without significant heterogeneity ( I²  = 0%, p -value > 0.05). In conclusion, this meta-analysis provides strong evidence that only some SNPs of CRP gene are associated with the risk for development of MetS; and this relationship does not exist in different ethnic populations.

Consensus paper of the WFSBP Task Force on Genetics: Genetics, epigenetics and gene expression markers of major depressive disorder and antidepressant response

Major depressive disorder (MDD) is a heritable disease with a heavy personal and socio-economic burden. Antidepressants of different classes are prescribed to treat MDD, but reliable and reproducible markers of efficacy are not available for clinical use. Further complicating treatment, the diagnosis of MDD is not guided by objective criteria, resulting in the risk of under- or overtreatment. A number of markers of MDD and antidepressant response have been investigated at the genetic, epigenetic, gene expression and protein levels. Polymorphisms in genes involved in antidepressant metabolism (cytochrome P450 isoenzymes), antidepressant transport (ABCB1), glucocorticoid signalling (FKBP5) and serotonin neurotransmission (SLC6A4 and HTR2A) were among those included in the first pharmacogenetic assays that have been tested for clinical applicability. The results of these investigations were encouraging when examining patient-outcome improvement. Furthermore, a nine-serum biomarker panel (including BDNF, cortisol and soluble TNF-α receptor type II) showed good sensitivity and specificity in differentiating between MDD and healthy controls. These first diagnostic and response-predictive tests for MDD provided a source of optimism for future clinical applications. However, such findings should be considered very carefully because their benefit/cost ratio and clinical indications were not clearly demonstrated. Future tests may include combinations of different types of biomarkers and be specific for MDD subtypes or pathological dimensions.

Relationship between polymorphisms in the CRP, LEP and LEPR genes and high sensitivity C-reactive protein levels in Spanish children

Background:

We investigated the association of single nucleotide polymorphisms (SNPs) in the C-reactive protein (

Methods:

We measured hs-CRP levels in 646 6–8-year-old and 707 12–16-year-old children using a high-sensitivity C-Reactive Protein ELISA kit. Four SNPs in the

Results:

The four CRP SNPs studied were significantly (p<0.05) associated with hs-CRP levels in both cohorts. Furthermore, two common CRP haplotypes (constructed using the SNPs in order: rs1205, rs1130864, rs1800947, rs2794521) ACGA and GCGG were associated with significantly lower CRP levels (p<0.05) at both ages. The LEPR SNPs rs1137100 (K109R) and rs1137101 (Q223R), and LEP SNP rs7799039 (G2548A) were also associated to hs-CRP levels (p<0.05) in both cohorts.

Conclusions:

hs-CRP levels in healthy Spanish children, besides being associated to common polymorphisms in the

Association of CRP gene polymorphisms with CRP levels, frailty and co-morbidity in an elderly Chinese population: results from RuLAS

OBJECTIVES

to examine the associations of two common CRP gene polymorphisms with CRP levels, frailty and co-morbidity in an elderly Chinese population.

DESIGN

a population-based cohort study.

SETTING AND PARTICIPANTS

we obtained data on 1,723 elderly participants aged 70-84 from the ageing arm of the Rugao Longevity and Ageing study (RuLAS), a population-based observational cohort study conducted in Rugao, Jiangsu province, China.

MEASUREMENTS

the genotyping of two common CRP gene polymorphisms (rs1205 and rs3093059) was performed. Items concerning the frailty index and co-morbidity were collected.

RESULTS

the mean age of the study population was 75.3 ± 3.9 years, and 53.5% (n = 922) were women. The minor allele frequencies of rs1205 and rs3093059 were 42.4% (C allele) and 16.9% (C allele), respectively. The polymorphisms rs1205 and rs3093059 were significantly associated with CRP levels (β = 0.113 and 0.222, all P < 0.001). Non-significant association between rs1205 and rs3093059 and frailty, as well as between rs3093059 and co-morbidity was observed. However, SNP rs1205 CC genotype had an increased odds of co-morbidity compared with the TT genotype (odds ratio (OR):1.53; 95% confidence interval (CI): 1.16-2.02). Each additional copy of the C allele of SNP rs1205 was associated with 1.23 times (95% CI: 1.07-1.41) odds of co-morbidity. The significance remained after controlling for covariates such as education level, etc.

CONCLUSIONS

among elderly Chinese individuals, two CRP gene polymorphisms were significantly associated with CRP levels. However, none of them was associated with frailty. The preliminary findings warrant further validations.

Fcγ receptors and ligands and cardiovascular disease

Fcγ receptors (FcγRs) classically modulate intracellular signaling on binding of the Fc region of IgG in immune response cells. How FcγR and their ligands affect cardiovascular health and disease has been interrogated recently in both preclinical and clinical studies. The stimulation of activating FcγR in endothelial cells, vascular smooth muscle cells, and monocytes/macrophages causes a variety of cellular responses that may contribute to vascular disease pathogenesis. Stimulation of the lone inhibitory FγcR, FcγRIIB, also has adverse consequences in endothelial cells, antagonizing NO production and reparative mechanisms. In preclinical disease models, activating FcγRs promote atherosclerosis, whereas FcγRIIB is protective, and activating FcγRs also enhance thrombotic and nonthrombotic vascular occlusion. The FcγR ligand C-reactive protein (CRP) has undergone intense study. Although in rodents CRP does not affect atherosclerosis, it causes hypertension and insulin resistance and worsens myocardial infarction. Massive data have accumulated indicating an association between increases in circulating CRP and coronary heart disease in humans. However, Mendelian randomization studies reveal that CRP is not likely a disease mediator. CRP genetics and hypertension warrant further investigation. To date, studies of genetic variants of activating FcγRs are insufficient to implicate the receptors in coronary heart disease pathogenesis in humans. However, a link between FcγRIIB and human hypertension may be emerging. Further knowledge of the vascular biology of FcγR and their ligands will potentially enhance our understanding of cardiovascular disorders, particularly in patients whose greater predisposition for disease is not explained by traditional risk factors, such as individuals with autoimmune disorders.

C-reactive protein gene variants: independent association with late-life depression and circulating protein levels

C-reactive protein (CRP) is a heritable biomarker of systemic inflammation that is commonly elevated in depressed patients. Variants in the CRP gene that influence protein levels could thus be associated with depression but this has seldom been examined, especially in the elderly. Depression was assessed in 990 people aged at least 65 years as part of the ESPRIT study. A clinical level of depression (DEP) was defined as having a score of ⩾16 on The Center for Epidemiologic Studies Depression scale or a diagnosis of current major depression based on the Mini-International Neuropsychiatric Interview and according to Diagnostic and Statistical Manual of Mental Disorders-IV criteria. Five single-nucleotide polymorphisms spanning the CRP gene were genotyped, and circulating levels of high-sensitivity CRP were determined. Multivariable analyses adjusted for socio-demographic characteristics, smoking, ischemic pathologies, cognitive impairment and inflammation-related chronic pathologies. The minor alleles of rs1130864 and rs1417938 were associated with a decreased risk of depression in women at Bonferroni-corrected significance levels (P=0.002). CRP gene variants were associated with serum levels in a gender-specific manner, but only rs1205 was found to be nominally associated with both an increased risk of DEP and lower circulating CRP levels in women. Variants of the CRP gene thus influence circulating CRP levels and appear as independent susceptibility factors for late-life depression.

The Relationship Between CRP Gene Polymorphism and the Serum Concentrations of C-Reactive Protein, Total Cholesterol and HDL Cholesterol in Suckling Piglets / Związek polimorfizmu genu CRP z koncentracją kodowanego białka C-reaktywnego, cholesterolu całkowitego i HDL-ch w surowicy krwi ssących prosiąt

The relationship between CRP gene (1271 G/A, 3’UTR) polymorphism and the serum levels of C-reactive protein (CRP), total cholesterol (Ch-T) and high density lipoprotein cholesterol (HDL-ch) was analysed in suckling crossbred [Polish Large White × Polish Landrace (♀) × × Duroc × Pietrain (♂)] piglets. CRP genotypes were identified by PCR-RFLP with Hinfi restriction enzyme. The levels of CRP, Ch-T, HDL-ch and white blood cell (WBC) counts were determined in blood samples collected from younger (21±3 days of age) and older piglets (35±3 days of age). There was a relationship between CRP gene (1271 G/A, 3’UTR) polymorphism and variations in the serum levels of CRP in piglets with normal WBC counts. The above relationship did not manifest itself in piglets with elevated WBC counts. The studied genotypes differed in their response to elevated WBC counts, and the noted differences were more pronounced in older piglets. The response of genotypes with weak CRP expression caused an increase in CRP levels and a decrease in the serum concentrations of Ch-T and HDL-ch. Such a response was not observed in the genotype with strong CRP expression.

Genetic variation in C-reactive protein in relation to colon and rectal cancer risk and survival

C-reactive protein (CRP), a biomarker of inflammation, has been shown to be influenced by genetic variation in the CRP gene. In this study, we test the hypothesis that genetic variation in CRP influences both the risk of developing colon and rectal cancer and survival. Two population-based studies of colon cancer (n = 1,574 cases, 1,970 controls) and rectal (n = 791 cases, 999 controls) were conducted. We evaluated four CRP tagSNPs: rs1205 (G > A, 3' UTR); rs1417938 (T > A, intron); rs1800947 (G > C, L184L); and rs3093075 (C > A, 3' flanking). The CRP rs1205 AA genotype was associated with an increased risk of colon cancer (OR 1.3, 95%CI 1.1-1.7), whereas the rs3093075 A allele was associated with a reduced risk of rectal cancer (OR 0.7, 95%CI 0.5-0.9). The strongest association for the rs1205 polymorphism and colon cancer was observed among those with KRAS2 mutations (OR 1.5, 95%CI 1.1-2.0). The CRP rs1205 AA genotype also was associated with an increased risk of CIMP+ rectal tumors (OR 2.5, 95%CI 1.2-5.3); conversely, the rs1417938 A allele was associated with a reduced risk of CIMP+ rectal tumors (OR 0.5, 95%CI 0.3-0.9). We observed interactions between CRP rs1800947 and BMI and family history of CRC in modifying risk of both colon and rectal cancer. These data suggest that genetic variation in the CRP gene influences risk of both colon and rectal cancer development.

Inflammatory gene variants in the Tsimane, an indigenous Bolivian population with a high infectious load

The Tsimane of lowland Bolivia are an indigenous forager-farmer population living under conditions resembling pre-industrial European populations, with high infectious morbidity, high infection and inflammation, and shortened life expectancy. Analysis of 917 persons ages 5 to 60+ showed that allele frequencies of 9 SNPs examined in the apolipoprotein E (apoE), C-reactive protein (CRP), and interleukin-6 (IL-6) genes differed from some European, African, and north Asian-derived populations. The apoE2 allele was absent, whereas four SNPs related to CRP and IL-6 were monomorphic: CRP (rs1800947, rs3093061, and rs3093062) and IL-6 (rs1800795). No significant differences in apoE, CRP, and IL-6 variants across age were found CRP levels were higher in carriers of two CRP proinflammatory SNPs, whereas they were lower in carriers of apoE4. Taken together the evidence for (1) different allele frequencies between the Tsimane and other populations and (2) the correlations of CRP and apoE alleles with blood CRP may suggest that these variants are under selection in response to a high infection environment.