Investigation of aPON1gene polymorphism (rs662 polymorphism) as predictor of subclinical atherosclerosis in patients with rheumatoid arthritis: Table 1

PON1 status and homocysteine levels as potential biomarkers for cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death. The mainly risks factors for CVD are diabetes, hypertension and high levels of homocysteine (Hcys), among others. Paraoxonase 1 (PON1) has been proposed as an antiatherogenic target for its ability to hydrolyzing oxi-Low-Density-Lipoproteins (LDL) and Hcys-thiolactone. Thus, the aim of the present study was to evaluate the association of Hcys levels, and the activities and concentration of PON1, as well as vitamin B from the diet with a risk for CVD.

METHODS

A case-control study was carry out in patients with cardiovascular diseases (CVD), Arterial hypertension, but not CVD (AH), and in healthy controls (control group) from the Mexican Institute of Social Security. Lipid profile, intake of vitamin B, Hcys, serum amyloid A (SAA), PON1 concentration, and PON1 activities (Arylesterase activity (ARE), Lactonase activity (LAC), and CMPA activity (CMPA)) were evaluated.

RESULTS

The CVD group had the highest concentration of Hcys and SAA than in the AH and control groups (p < 0.01). ARE, LAC, and CMPA activities and PON1 concentration were lowest in the CVD group. A positive-independent association between Hcys levels and CVD was found (OR = 2.09; 95% CI: 1.69-2.56) and this increase when it was adjusted by age, BMI, ApoA1, vitamin B intake, SAA, and PON1 (OR = 14.41; 95% CI: 1.75-118.71). LAC and CMPA, as well as PON1 concentration, were inversely associated with CVD.

CONCLUSION

LAC activity, PON1 concentration, and Hcys levels might be good biomarkers for CVD and their association could be modified by the intake of vitamin B.

PON-1 haplotype (-108C>T, L55M, and Q192R) modulates the serum levels and activity PONase promoting an atherogenic lipid profile in rheumatoid arthritis patients

INTRODUCTION/OBJECTIVE

Paraoxonase 1 (PON1) promotes antioxidant and antiatherogenic activity related to the hydrolysis of oxidized lipids of low-density lipoproteins. In rheumatoid arthritis (RA) patients, it has been reported that low PON1 activity is related to an impaired lipid profile, increasing cardiovascular risk (CVR). The goal of this study was to analyze the effect of common PON1 polymorphisms and haplotypes on enzymatic activity, PON1 serum levels (PON1s), and lipid parameters related to atherogenic profile in RA patients.

METHODS

A cross-sectional study was carried out on 250 Mexican patients with RA. The lipid profile was determined by colorimetric tests. The PON1 activity (CMPAase) was measured by spectrophotometry. The levels of PON1s were determined by ELISA, and the polymorphisms in the PON-1 gene (-108C>T, L55M, and Q192R) were genotyped by the PCR-RFLP method. The haplotypes were estimated and statistical analysis was performed.

RESULTS

The median of the CMPAase activity and PON1 levels was 13.91 U/mL and 24.75 ng/mL, respectively. The CMPAase activity was significantly lower in carriers of -108TT and 192QQ genotypes (β = - 4.09, P = 0.001 and β = - 3.73, P = 0.002, respectively); moreover, the PON1 levels were lower in 192Q allele carriers (P < 0.01). The TLQ haplotype was associated with CMPAase activity < 13.91 U/mL (OR = 2.29, P < 0.001), as well as with levels of PON1s < 24.75 ng/mL (OR = 1.65, P = 0.017). In this study, the CMPAase activity (< 13.91 U/mL) showed a positive association with lower levels of high-density lipoprotein cholesterol (HDL-c; < 40/50 mg/dL), and with a triglycerides/HDL-c ratio > 3%, and a total cholesterol/HDL-c ratio > 4.5/5%, all representatives of an atherogenic risk lipid profile.

CONCLUSIONS

PON1 polymorphisms modulate the CMPAase activity and PON1 levels in Mexican patients with RA. The CMPAase activity < 13.91 U/mL is associated with an atherogenic lipid profile, independently of inflammation markers and treatment with anti-rheumatic drugs. Key Points •The haplotype TLQ is a marker for low PONase activity in rheumatoid arthritis. •The haplotype TLQ is a marker for low PON1 serum levels in rheumatoid arthritis. •The enzymatic PON1 activity represents the best marker for an atherogenic lipid profile in rheumatoid arthritis, in comparison with PON1 levels. •The haplotype TLQ is a marker of low PON1 activity, levels of PON1s, and atherogenic lipid profile, independent of treatment therapy in rheumatoid arthritis.

Carotid plaques in adult rheumatoid arthritis patients; association with paroxonase 1 enzymatic activity and Q192R paroxonase 1 gene polymorphism

Paroxonase 1 (PON 1) enzymatic activity and Q192R PON polymorphism has been implicated with greater cardiovascular risk in general population. Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized with increased inflammatory markers leading to increased cardiovascular morbidity. The aim of the work was to study association between PON1 enzymatic activity & gene polymorphism with carotid plaques in RA patients. This case-control study was carried out at Zagazig University Hospitals on 99 subjects divided randomly into two groups; 48 RA patients and 51 controls. RA patients fulfilled the revised 2010 EULAR/ACR classification criteria of RA. All patients were subjected to history taking, clinical evaluation, laboratory investigations & plain X-rays. Carotid intima-media thickness (CIMT) and PON1 enzyme assay & genotyping were done for both groups. PON1 enzyme levels were significantly higher in patients than controls. Also, there was a significant negative correlation of PON1 enzyme activity with increased CIMT & plaques. The cut-off value of PON1 enzyme level that had the highest CVD prediction was 4.2 U/ml. Although PON1 genotyping was insignificantly different between patients and controls, patients with QQ genotype had the lowest PON1 activity then patients with QR genotype then RR genotype. In RA patients, decreased serum PON1 enzymatic activity and QQ genotyping of Q192R PON polymorphism was associated with increased CIMT & plaques. Serum PON1 could be a good marker for atherosclerosis prediction in RA patients at cutoff 4.2 U/ml.

Effects of tofacitinib and other DMARDs on lipid profiles in rheumatoid arthritis: implications for the rheumatologist

Cardiovascular (CV) morbidity and mortality are increased in patients with active, untreated rheumatoid arthritis (RA), despite lower levels of total and low-density lipoprotein cholesterol reported in individuals with active RA compared with those without RA. Alterations in non-traditional lipid assessments, such as high-density lipoprotein (HDL) function and HDL-associated proteins, have been described in patients with active RA, including elevated HDL-associated serum amyloid A and decreased paraoxonase-1 activity. We review changes in both traditional lipoprotein concentrations and non-traditional lipoprotein assessments in multiple studies of treatment with disease-modifying antirheumatic drugs (DMARDs), including non-biologic and biologic DMARDs and tofacitinib. In addition, data from a recently published clinical trial with tofacitinib that describe a potential mechanism for suppression of cholesterol levels in active RA patients are reviewed. Finally, CV event data from various studies of DMARDs are presented, and the current management of RA patients with regard to the CV risk is reviewed.

Correlation of Paraoxonase Status with Disease Activity Score and Systemic Inflammation in Rheumatoid Arthritic Patients

INTRODUCTION

Despite, various preventive efforts on conventional cardiovascular disease (CVD) risk factors, the incidence of CVD in rheumatoid arthritis (RA) patients increases continuously. To solve this conundrum one needs more investigations.

AIM

The present study was conducted to evaluate the plasma paraoxonase (PON) activity along with the markers of systemic inflammation, oxidative stress and disease activity score-28 (DAS28) in RA patients and clarify their role in determining the probability of RA patients to develop future CVD risk.

MATERIALS AND METHODS

Plasma PON, total antioxidant activity (TAA), C-reactive protein (CRP), synovial interleukin-6 (IL-6) and erythrocyte malondialdehyde (MDA) levels were estimated in 40 RA patients aged 40-55 years aged and 40 age-matched healthy controls. The data obtained were compared statistically by using Student's t-test and Pearson correlation test.

RESULTS

Besides dyslipidaemia, marked reduction in plasma PON and TAA (p< 0.05) were observed in RA patients as compared with that of healthy controls. Erythrocyte MDA, plasma CRP and synovial IL-6 levels were increased significantly (p<0.05) in RA patients. PON was negatively correlated with MDA (r = - 0.672; p < 0.001), CRP (r = -0.458; p<0.05), IL-6 (r = -0.426; p<0.05) and DAS28 (r = -0.598; p < 0.001), and positively correlated with HDL cholesterol (r = 0.648; p<0.001) and TAA (r = 0.608; p< 0.001) levels in RA patients.

CONCLUSION

Alteration in PON activity might contribute to the progression of future CVD risk in RA patients, which may result from interplay of several confounding factors, such as inflammation, oxidative stress and dyslipidaemia. Furthermore, plasma PON activity, CRP and TAA levels could be considered as non-traditional factors to predict CVD risk. Thus, it is suggested that future drugs could be developed to target the non-traditional risk factors in RA patients.

Can the ankle brachial pressure index (ABPI) and carotis intima media thickness (CIMT) be new early stage markers of subclinical atherosclerosis in patients with rheumatoid arthritis?

BACKGROUND

It takes years for atherosclerosis to manifest symptoms. However, it needs to be identified earlier because of the premature cardiovascular risk factors in patients with rheumatoid arthritis (RA). In this study, we aimed to investigate the effect of atherosclerosis on the ankle brachial pressure index (ABPI) and carotis intima media thickness (CIMT) in patients with RA.

METHODS

RA patients attending the rheumatology clinic were examined retrospectively; then we called them for the measurements of ABPI and CIMT prospectively. Subjects were divided into four groups, as follows (Table 1): group 1 comprised RA patients with an ABPI less than 0.9; group 2 included RA patients with an ABPI between 0.9 and 1.2; group 3 was made up of RA patients with an ABPI greater than 1.2; and group 4 included patients without RA with an ABPI between 0.9 and 1.2 as a control group. Patients' demographic data were recorded. Hypertension (HT), diabetes mellitus, ABPI and CIMT measurements were taken by specialists. Duration of RA and disease scores (disease activity score-28, health assessment questionnaire score and visual assessment score) were recorded.

RESULTS

The prevalence of peripheral vascular disease in patients with RA was twice as high as that in the normal population of equivalent age. Patients in group 2, with RA and normal ABPI, exhibited a significant higher mean in CIMT (mm) compared with the control group (p < 0.01), despite having normal ABPI. This confirms that these patients have a higher risk of stroke compared with the control group. Group 1's newly diagnosed HT (p < 0.01) and systolic blood pressure (SBP) values (p < 0.01) were higher and statistically significant when compared with the group 4 (control group); in addition, significant plaque levels were observed in the carotid arteries (p < 0.01). Group 3 patients had a similar history of HT and increased SBP compared with patients in group 4 (p < 0.01), and had similar characteristics to with group 1. No statistically significant differences were found between the groups in terms of inflammatory markers such as C-reactive protein and rheumatoid factor, anti-cyclic citrullinated peptide and white blood cell counts.

CONCLUSION

Based on the present findings, patients with RA need to be evaluated in the early stage of the disease for subclinical peripheral artery disease using the ABPI, as well as CIMT, which is also a non-invasive technique, in terms of cerebrovascular events. Inflammatory markers exhibited no statistically significant difference. We think that the atherosclerotic process stems not only from the inflammatory effects of RA, but also perhaps from its immunological nature.

A variant in the osteoprotegerin gene is associated with coronary atherosclerosis in patients with rheumatoid arthritis: results from a candidate gene study

Objective: Patients with rheumatoid arthritis (RA) have accelerated atherosclerosis, but there is limited information about the genetic contribution to atherosclerosis in this population. Therefore, we examined the association between selected genetic polymorphisms and coronary atherosclerosis in patients with RA. Methods: Genotypes for single-nucleotide polymorphisms (SNPs) in 152 candidate genes linked with autoimmune or cardiovascular risk were measured in 140 patients with RA. The association between the presence of coronary artery calcium (CAC) and SNP allele frequency was assessed by logistic regression with adjustment for age, sex, and race. To adjust for multiple comparisons, a false discovery rate (FDR) threshold was set at 20%. Results: Patients with RA were 54 ± 11 years old and predominantly Caucasian (89%) and female (69%). CAC was present in 70 patients (50%). A variant in rs2073618 that encodes an Asn3Lys missense substitution in the osteoprotegerin gene (OPG, TNFRSF11B) was significantly associated with the presence of CAC (OR = 4.09, p < 0.00026) and withstands FDR correction. Conclusion: Our results suggest that a polymorphism of the TNFRSF11B gene, which encodes osteoprotegerin, is associated with the presence of coronary atherosclerosis in patients with RA. Replication of this finding in independent validation cohorts will be of interest.