Serum paraoxonase levels in patients with acute liver disease

Effects of One-Year Tofacitinib Therapy on Lipids and Adipokines in Association with Vascular Pathophysiology in Rheumatoid Arthritis

Background: Cardiovascular (CV) morbidity, mortality and metabolic syndrome are associated with rheumatoid arthritis (RA). A recent trial has suggested increased risk of major CV events (MACE) upon the Janus kinase (JAK) inhibitor tofacitinib compared with anti-tumor necrosis factor α (TNF-α) therapy. In our study, we evaluated lipids and other metabolic markers in relation to vascular function and clinical markers in RA patients undergoing one-year tofacitinib therapy. Patients and methods: Thirty RA patients treated with either 5 mg or 10 mg bid tofacitinib were included in a 12-month follow-up study. Various lipids, paraoxonase (PON1), myeloperoxidase (MPO), thrombospondin-1 (TSP-1) and adipokine levels, such as adiponectin, leptin, resistin, adipsin and chemerin were determined. In order to assess flow-mediated vasodilation (FMD), common carotid intima-media thickness (IMT) and arterial pulse-wave velocity (PWV) ultrasonography were performed. Assessments were carried out at baseline, and 6 and 12 months after initiating treatment. Results: One-year tofacitinib therapy significantly increased TC, HDL, LDL, APOA, APOB, leptin, adipsin and TSP-1, while significantly decreasing Lp(a), chemerin, PON1 and MPO levels. TG, lipid indices (TC/HDL and LDL/HDL), adiponectin and resistin showed no significant changes. Numerous associations were found between lipids, adipokines, clinical markers and IMT, FMD and PWV (p < 0.05). Regression analysis suggested, among others, association of BMI with CRP and PWV (p < 0.05). Adipokines variably correlated with age, BMI, CRP, CCP, FMD, IMT and PWV, while MPO, PON1 and TSP-1 variably correlated with age, disease duration, BMI, RF and PWV (p < 0.05). Conclusions: JAK inhibition by tofacitinib exerts balanced effects on lipids and other metabolic markers in RA. Various correlations may exist between metabolic, clinical parameters and vascular pathophysiology during tofacitinib treatment. Complex assessment of lipids, metabolic factors together with clinical parameters and vascular pathophysiology may be utilized in clinical practice to determine and monitor the CV status of patients in relation with clinical response to JAK inhibition.

Association between PON1 rs662 polymorphism and coronary artery disease

BACKGROUND/OBJECTIVES

Paraoxonase 1 (PON1) is a plasma enzyme that is capable of inhibiting the progression of atherosclerosis, and is associated with susceptibility of coronary artery disease (CAD). PON protein expression is present in human aortic tissue and it plays an important role in the progression of atherosclerosis. This study aimed to investigate PON1 immunohistochemistry in human coronary arteries, determine its polymorphisms and plasma status, and analyze its association with the risk of CAD.

SUBJECTS/METHODS

PON1 expression in human coronary artery tissues was detected by immunohistochemical staining. PON1 polymorphisms were determined by polymerase chain reaction direct sequencing in 2456 unrelated Chinese Han individuals. Serum PON1 levels were indirectly reflected by PON1 activity towards paraoxon and phenylacetate by spectrophotometry, and by its concentrations using a human enzyme-linked immunosorbent assay.

RESULTS

Immunohistochemical analysis showed that PON1 expression was lower in atherosclerotic arteries than in normal arteries. PON1 Q192R (rs662) had a significant effect on the risk of CAD (P=0.001). In a logistic regression model, after adjusting for conventional risk factors of CAD, 192R allele carriers had a significantly higher risk of CAD than other allele carriers. Serum PON1 activity and concentrations were significantly reduced in CAD patients compared with controls (P<0.05), and highly associated with the R allele.

CONCLUSIONS

Low PON1 expression in human atherosclerotic coronary arteries is associated with CAD. Moreover, PON1 Q192R polymorphism is significantly associated with susceptibility of CAD in the Chinese Han population, and the 192R allele might be an independent predictor for CAD.