Variants of PCSK9 Gene Are Associated with Subclinical Atherosclerosis and Cardiometabolic Parameters in Mexicans. The GEA Project

Atherosclerosis and Toll-Like Receptor4 (TLR4), Lectin-Like Oxidized Low-Density Lipoprotein-1 (LOX-1), and Proprotein Convertase Subtilisin/Kexin Type9 (PCSK9)

Atherosclerosis is a leading cause of death in the world. A significant body of evidence suggests that inflammation and various players are implicated and have pivotal roles in the formation of atherosclerotic plaques. Toll-like receptor 4 (TLR4) is linked with different stages of atherosclerosis. This receptor is highly expressed in the endothelial cells (ECs) and atherosclerotic plaques. TLR4 activation can lead to the production of inflammatory cytokines and related responses. Lectin-like oxidized low-density lipoprotein-1 (LOX-1), an integral membrane glycoprotein with widespread expression on the ECs, is involved in atherosclerosis and has some common pathways with TLR4 in atherosclerotic lesions. In addition, proprotein convertase subtilisin/kexin type9 (PCSK9), which is a regulatory enzyme with different roles in cholesterol uptake, is implicated in atherosclerosis. At present, TLR4, PCSK9, and LOX-1 are increasingly acknowledged as key players in the pathogenesis of atherosclerotic cardiovascular diseases. Herein, we presented the current evidence on the structure, functions, and roles of TLR4, PCSK9, and LOX-1 in atherosclerosis.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) as a marker of coronary lesion severity in stable coronary artery disease (CAD) patients

Coronary artery disease (CAD) remains a significant global health concern with considerable high morbidity and mortality and its development is influenced by various genetic and environmental factors. Proprotein convertase subtilisin/kexin type 9 (PCSK9) is a vital regulator of low-density lipoprotein receptor (LDLR) metabolism, directly impacting serum cholesterol levels. However, its role in development of CAD is not fully understood. The aim of this study was to assess the association between the level of PCSK9 and coronary lesion severity in patients with CAD. A case-control study using consecutive sampling was conducted among CAD patients at H. Adam Malik General Hospital and Murni Teguh Memorial Hospital, Medan, Indonesia. A total of 200 CAD patients were divided into two groups based on the SYNTAX score: control (score ≤22, n=100) and case (score >22, n=100). Plasma PCSK9 levels were measured from venous blood using quantitative sandwich enzyme immunoassay. The Chi-squared test was used to analyze the data. Our data suggested that PCSK9 level was associated with coronary lesion severity (p<0.001) of which high PCSK9 level was associated with severe coronary lesion. We also found that hypertension (p<0.001), smoking (p=0.072), diabetes (p<0.001), dyslipidemia (p<0.001), obesity (p=0.023), and family history (p=0.001) were associated with lesion severity. Using the receiver operating characteristic (ROC) curve analysis, the cut-off 70.35 ng/mL of PCSK9 had sensitivity 75% and specificity 78% to predict severe coronary lesion. This study highlights that PCSK9 level has moderate sensitivity and specificity to predict the coronary lesion severity among CAD patients.

Polymorphisms rs562556 and rs2479409 of the PCSK9 gene associated with obesity and cardiovascular disease

OBJECTIVE

The primary objective was to comprehensively assess the association between single nucleotide polymorphisms (rs562556 and rs2479409) in the PCSK9 gene with biochemical parameters - C-reactive protein (CRP), glucose (GLU), triglyceride (TAG), low-density lipoprotein cholesterol (LDL CHOL), non-high-density lipoprotein cholesterol (non HDL CHOL), high-density lipoprotein cholesterol (HDL CHOL), cholesterol (CHOL), and anthropometric parameters (visceral fat), overweight/obesity and cardiovascular risk.

METHODS

A total of 71 women aged 23-64 years were divided into three groups based on body mass index (BMI). BMI ≥ 25/≥ 30 kg/m2 was the criterion for assessment of overweight/obesity. Anthropometric, biochemical and genetic examinations were performed on the probands. Changes in markers in each group and their association with cardiovascular risk were monitored.

RESULTS

We can conclude that in our study population we observed differences between the BMI categories for biochemical markers (CRP, LDL CHOL, non HDL CHOL, HDL CHOL, LDL CHOL) and anthropometric marker (visceral fat). Atherogenic index of plasma (AIP), Castelli's Risk Index I (CRI-I) and atherogenic coefficient (AC) confirmed high cardiovascular risk for the obese women category (0.045); (< 0.013); (< 0.010). Genotype and allele frequencies for the PCSK9 gene in the overweight and obese groups showed higher allele frequencies of allele A for both polymorphisms of the gene.

CONCLUSIONS

PCSK9 gene expression is associated with biological processes such as lipid metabolism and inflammation. Cholesterol-lowering therapies are the gold standard for reducing the risk of cardiovascular mortality and morbidity. Administration of monoclonal antibodies (mAbs) against PCSK9 is a novel lipid-lowering therapeutic approach in adults to reduce the risk of cardiovascular disease.

Increased Carotid Intima-Media Thickness in Asymptomatic Individuals Is Associated with the PCSK9 (rs2149041) Gene Polymorphism in the Mexican Mestizo Population: Results of the GEA Cohort

The increase in carotid intima-media thickness (CIMT) and coronary artery calcification (CAC) are features of subclinical atherosclerosis that might be determined by the genetic background of patients. Among the multiple risk factors, the proprotein convertase subtilisin kexin type 9 (PCSK9) has a great impact on atheroma development. Then, we focused on the potential association of the PCSK9 gene polymorphism (rs2149041) with the risk of an increased CIMT. We included 881 unrelated, asymptomatic individuals (732 normal CIMT and 149 increased CIMT) who lacked coronary calcification (CAC score = 0). Under the recessive inheritance model and adjusted by several cardiovascular risk factors, the rs2149041 polymorphism, determined by TaqMan genotyping assay, was associated with a high risk of increased CIMT (OR = 2.10, 95% IC = 1.26–3.47, P recessive = 0.004). Our results suggest that the rs2149041 polymorphism could be a risk marker for increased CIMT in asymptomatic individuals without coronary artery disease determined by the absence of a CAC score.

Long-Term Exposure to Ozone and Fine Particulate Matter and Risk of Premature Coronary Artery Disease: Results from Genetics of Atherosclerotic Disease Mexican Study

(1) Background: Epidemiological studies have identified associations between fine particulate matter (PM2.5) and ozone exposure with cardiovascular disease; however, studies linking ambient air pollution and premature coronary artery disease (pCAD) in Latin America are non-existing. (2) Methods: Our study was a case−control analysis nested in the Genetics of Atherosclerotic Disease (GEA) Mexican study. We included 1615 participants (869 controls and 746 patients with pCAD), recruited at the Instituto Nacional de Cardiología Ignacio Chávez from June 2008 to January 2013. We defined pCAD as history of myocardial infarction, angioplasty, revascularization surgery or coronary stenosis > 50% diagnosed before age 55 in men and age 65 in women. Controls were healthy individuals without personal or family history of pCAD and with coronary artery calcification equal to zero. Hourly measurements of ozone and PM2.5 from the Atmospheric Monitoring System in Mexico City (SIMAT in Spanish; Sistema de Monitero Atmosférico de la Ciudad de México) were used to calculate annual exposure to ozone and PM2.5 in the study participants. (3) Results: Each ppb increase in ozone at 1-year, 2-year, 3-year and 5-year averages was significantly associated with increased odds (OR = 1.10; 95% CI: 1.03−1.18; OR = 1.17; 95% CI: 1.05−1.30; OR = 1.18; 95% CI: 1.05−1.33, and OR = 1.13; 95% CI: 1.04−1.23, respectively) of pCAD. We observed higher risk of pCAD for each 5 µg/m3 increase only for the 5-year average of PM2.5 exposure (OR = 2.75; 95% CI: 1.47−5.16), compared to controls. (4) Conclusions: Ozone exposure at different time points and PM2.5 exposure at 5 years were associated with increased odds of pCAD. Our results highlight the importance of reducing long-term exposure to ambient air pollution levels to reduce the burden of cardiovascular disease in Mexico City and other metropolitan areas.

Osteopontin Gene Polymorphisms Are Associated with Cardiovascular Risk Factors in Patients with Premature Coronary Artery Disease

Osteopontin (OPN) is considered a clinical predictor of cardiovascular disease. We aimed to evaluate the association of the OPN gene polymorphisms rs2728127 and rs11730582 with the development of premature coronary artery disease (pCAD), cardiovascular risk factors, and cardiometabolic parameters. We evaluated 1142 patients with pCAD and 1073 controls. Both polymorphisms were determined by Taqman assays. Similar allele and genotype frequencies were observed in both groups; additionally, an association of these polymorphisms with CAD and cardiometabolic parameters was observed in both groups. In patients with pCAD, the rs11730582 was associated with a high risk of hypoadiponectinemia (OR = 1.300, P _additive = 0.003), low risk of hypertension (OR = 0.709, P _{codominant 1} = 0.030), and low risk of having high non-HDL cholesterol (OR = 0.637, P _additive = 0.038). In the control group, the rs2728127 was associated with a low risk of fatty liver (OR = 0.766, P _additive = 0.038); while the rs11730582 was associated with a low risk of hypoadiponectinemia (OR = 0.728, P _dominant = 0.022), and risk of having elevated apolipoprotein B (OR = 1.400, P _dominant = 0.031). Our results suggest that in Mexican individuals, the rs11730582 and rs2728127 OPN gene polymorphisms are associated with some abnormal metabolic variables in patients with pCAD and controls.

Association between the rs615563 variant of PCSK9 gene and circulating lipids and Type 2 diabetes

Objective

Many different genetic variants of proprotein convertase subtilisin kexin 9 (PCSK9) are related to the serum levels of cholesterol and LDL cholesterol (LDL-C). The rs615563 variant of PCSK9 (a gain-of-function mutation) is associated with increased triglycerides and cholesterol levels, but its association with the incidence of diabetes is not well defined. This study aimed to investigate the relationship between the PCSK9 rs615563 variant with the incidence of type 2 diabetes. The data reported in this study are based on subsamples from a 5-year (2009–2014) cohort study of the adult population (590 subjects) aged 20 years and older. The rs615563 polymorphism was genotyped using polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) analysis.

Results

The distribution of PCSK9 rs615563 genotypes was not significantly different between the diabetic and non-diabetic individuals. The incidence of diabetes after five-years of follow-up was not different between the genotypes. Our findings also showed no significant relationship between this polymorphism and serum lipid parameters. The data extracted from our cohort study do not support the findings that the gain-of-function mutations of PCSK9 predispose to the incidence of type 2 diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05723-4.