Decreased Serum Stromal Cell-Derived Factor-1 in Patients with Familial Hypercholesterolemia and Its Strong Correlation with Lipoprotein Subfractions.

Stromal cell-derived factor-1 (SDF-1) is a chemokine that exerts multifaceted roles in atherosclerosis. However, its association with hyperlipidemia is contradictory. To date, serum SDF-1 and its correlations with lipid fractions and subfractions in heterozygous familial hypercholesterolemia (HeFH) have not been investigated. Eighty-one untreated patients with HeFH and 32 healthy control subjects were enrolled in the study. Serum SDF-1, oxidized LDL (oxLDL) and myeloperoxidase (MPO) were determined by ELISA. Lipoprotein subfractions were detected by Lipoprint. We diagnosed FH using the Dutch Lipid Clinic Network criteria. Significantly lower serum SDF-1 was found in HeFH patients compared to healthy controls. Significant negative correlations were detected between serum total cholesterol, triglycerides, LDL-cholesterol (LDL-C), apolipoprotein B100 (ApoB100) and SDF-1. Furthermore, serum SDF-1 negatively correlated with VLDL and IDL, as well as large LDL and large and intermediate HDL subfractions, while there was a positive correlation between mean LDL-size, small HDL and SDF-1. SDF-1 negatively correlated with oxLDL and MPO. A backward stepwise multiple regression analysis showed that the best predictors of serum SDF-1 were VLDL and oxLDL. The strong correlation of SDF-1 with lipid fractions and subfractions highlights the potential common pathways of SDF-1 and lipoprotein metabolism, which supports the role of SDF-1 in atherogenesis.

Assessment of amino-terminal C-type natriuretic peptide serum level and its correlation with high-density lipoprotein structure and function in patients with end stage renal disease before and after kidney transplantation.

We aimed to investigate serum amino-terminal C-type natriuretic peptide (NT-proCNP) and its relationship with quantitative and qualitative HDL-parameters in patients with end-stage renal disease (ESRD) before, then 1 and 6 months after kidney transplantation (TX). Seventy patients (47 males, 23 females, mean age 51.7 ± 12.4 years) were enrolled in a prospective follow-up study. We examined serum creatinine, C-reactive protein, procalcitonin, fasting glucose and lipid parameters before, then 1 and 6 months after TX. High-density lipoprotein- (HDL)-associated paraoxonase-1 (PON1) paraoxonase and arylesterase activities were measured spectrophotometrically. Lipoprotein subfractions were determined by Lipoprint. NT-proCNP and oxidized low-density lipoprotein (oxLDL) levels were measured by ELISA. Mean NT-proCNP was 45.8 ± 21.9 pmol/L before renal transplantation and decreased markedly 1 month and 6 months after transplantation (5.3 ± 2.5 and 7.7 ± 4.9 pmol/L, respectively, P = 1 × 10-4). During the 6 months' follow-up, PON1 arylesterase, paraoxonase and salt-stimulated paraoxonase activities improved. NT-proCNP positively correlated with procalcitonin and creatinine and negatively with GFR, LDL-cholesterol (LDL-C) and HDL-cholesterol (HDL-C). There was a negative correlation between serum NT-proCNP and PON1 arylesterase activity. According to the multiple regression analysis, the best predicting variables of NT-proCNP were serum procalcitonin, creatinine and PON1 arylesterase activity. NT-proCNP might be a novel link between HDL dysfunction and impaired vascular function in ESRD, but not after kidney transplantation. Further studies in larger populations are needed to clarify the exact role of NT-proCNP in the risk prediction for cardiovascular comorbidities and complications in ESRD.

Sphingosine 1-Phosphate and Apolipoprotein M Levels and Their Correlations with Inflammatory Biomarkers in Patients with Untreated Familial Hypercholesterolemia.

High-density lipoprotein (HDL)-bound apolipoprotein M/sphingosine 1-phosphate (ApoM/S1P) complex in cardiovascular diseases serves as a bridge between HDL and endothelial cells, maintaining a healthy endothelial barrier. To date, S1P and ApoM in patients with untreated heterozygous familial hypercholesterolemia (HeFH) have not been extensively studied. Eighty-one untreated patients with HeFH and 32 healthy control subjects were included in this study. Serum S1P, ApoM, sCD40L, sICAM-1, sVCAM-1, oxLDL, and TNFα concentrations were determined by ELISA. PON1 activities were measured spectrophotometrically. Lipoprotein subfractions were detected by Lipoprint. We diagnosed FH using the Dutch Lipid Clinic Network criteria. Significantly higher serum S1P and ApoM levels were found in HeFH patients compared to controls. S1P negatively correlated with large HDL and positively with small HDL subfractions in HeFH patients and the whole study population. S1P showed significant positive correlations with sCD40L and MMP-9 levels and PON1 arylesterase activity, while we found significant negative correlation between sVCAM-1 and S1P in HeFH patients. A backward stepwise multiple regression analysis showed that the best predictors of serum S1P were large HDL subfraction and arylesterase activity. Higher S1P and ApoM levels and their correlations with HDL subfractions and inflammatory markers in HeFH patients implied their possible role in endothelial protection.

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.

Changes in serum pigment epithelium-derived factor levels after kidney transplantation in patients with end-stage renal disease.

BACKGROUND: Pigment epithelium-derived factor (PEDF) is a serin protease inhibitor and a potent inhibitor of angiogenesis. Its serum level has significant associations with metabolic parameters. However, little is known about the association between PEDF levels and lipid parameters in renal transplanted (TX) patients. Therefore, our aim was to investigate the relationship between PEDF level and lipid parameters in TX patients. METHODS: Seventy TX patients (47 males, 23 females, mean age 51.7 ± 12.4 years) and 34 healthy controls were enrolled. We examined the serum creatinine, C-reactive protein, fasting glucose and lipid parameters right before, then 1 and 6 months after TX. High-density lipoprotein (HDL)-associated paraoxonase-1 (PON1) activities were measured spectrophotometrically. Lipoprotein subfractions were determined by Lipoprint. PEDF and oxidized low-density liporotein (oxLDL) levels were measured by ELISA. RESULTS: Before transplantation, patients had had a significantly higher PEDF level compared to control subjects (p < 0.001). One month after transplantation, their PEDF level decreased significantly reaching the healthy controls' level, and this lower level was maintained during the 6 months follow-up period as well. The initial oxLDL level was significantly higher, while PON1 activities were significantly lower in the patient group compared to the control group. We found a significant positive correlation between PEDF and total cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride, oxLDL and small HDL subfraction; while negative correlations were found between PEDF and mean LDL size and large HDL subfraction during the entire follow-up period. CONCLUSION: PEDF may play an important role in the increased oxidative stress and enhanced atherogenesis in renal transplant patients.

Determination of Serum Progranulin in Patients with Untreated Familial Hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant trait characterized by elevated LDL-C concentrations and is associated with an increased risk of premature atherosclerosis. Progranulin (PGRN) is a multifunctional protein that is known to have various anti-atherogenic effects. To date, the use of serum PGRN in patients with FH has not been studied. METHODS: In total, 81 untreated patients with heterozygous FH (HeFH) and 32 healthy control subjects were included in this study. Serum PGRN, sICAM-1, sVCAM-1, oxLDL and TNFα concentrations were determined by ELISA. Lipoprotein subfractions were detected by Lipoprint. We diagnosed FH using the Dutch Lipid Clinic Network criteria. RESULTS: We could not find a significant difference between the PGRN concentrations of the HeFH patients and controls (37.66 ± 9.75 vs. 38.43 ± 7.74 ng/mL, ns.). We found significant positive correlations between triglyceride, TNFα, sVCAM-1, the ratio of small HDL subfraction and PGRN, while significant negative correlations were found between the ratio of large HDL subfraction and PGRN both in the whole study population and in FH patients. PGRN was predicted by sVCAM-1, logTNFα and the ratio of small HDL subfraction. CONCLUSIONS: The strong correlations between HDL subfractions, inflammatory markers and PGRN suggest that PGRN may exert its anti-atherogenic effect in HeFH through the alteration of HDL composition and the amelioration of inflammation rather than through decreasing oxidative stress.

Changes of Metabolic Biomarker Levels upon One-Year Anti-TNF-α Therapy in Rheumatoid Arthritis and Ankylosing Spondylitis: Associations with Vascular Pathophysiology.

BACKGROUND: Cardiovascular (CV) morbidity, mortality, and metabolic syndrome are associated with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Here, lipids and other metabolic markers in relation to vascular function and clinical markers were evaluated in RA and AS patients undergoing one-year anti-TNF therapy. PATIENTS AND METHODS: Fifty-three patients including 36 RA patients treated with either etanercept (ETN) or certolizumab pegol (CZP) and 17 AS patients treated with ETN were included in a 12-month follow-up study. Various lipids, paraoxonase (PON) and arylesterase (ARE) activities, myeloperoxidase (MPO) and adipokine levels were determined overtime. Ultrasonography was performed to determine flow-mediated vasodilation (FMD), common carotid intima-media thickness (ccIMT), and arterial pulse-wave velocity (PWV) in all patients. All assessments were performed at baseline and 6 and 12 months after treatment initiation. RESULTS: Anti-TNF therapy decreased ARE activity, MPO, adiponectin, and chemerin levels after 12 months (p < 0.05). Lipids, PON activity, and leptin remained unchanged. Regression analyses suggested variable associations of IMT, PWV, and FMD with ARE, MPO, leptin, and lipids (p < 0.05). On the other hand, these metabolic parameters were significantly associated with disease duration, CV history, CRP, obesity, PWV, and IMT (p < 0.05). One-year anti-TNF treatment together with baseline leptin (p = 0.039) or CRP (p = 0.016) levels determined 12 months of lipid changes overtime. TNF inhibition together with baseline disease activity determined ARE activity changes (p = 0.046). Anti-TNF therapy and baseline chemerin levels determined IMT changes overtime (p = 0.003). CONCLUSIONS: Assessment of various metabolic parameters together with disease activity, CRP, and ultrasound-based techniques may exert additional value in determining CV burden and in monitoring the effects of biologics on preclinical vascular pathophysiology.

Low Levels of Serum Fetuin-A and Retinol-Binding Protein 4 Correlate with Lipoprotein Subfractions in Morbid Obese and Lean Non-Diabetic Subjects.

BACKGROUND: Fetuin-A and retinol-binding protein 4 (RBP4) are secreted as both hepatokine and adipokine. These are involved in insulin resistance, obesity-related dyslipidemia, and atherosclerosis. To date, correlations of circulating fetuin-A and RBP4 with lipoprotein subfractions as well as high-density lipoprotein (HDL)-linked proteins have not been entirely investigated in morbid obese and lean non-diabetic subjects. METHODS: One-hundred obese non-diabetic patients (body mass index, BMI: 42.5 ± 8.1 kg/m2) along with 32 gender and age-matched normal weight controls (BMI: 24.5 ± 2.5 kg/m2) were enrolled in our study. Serum fetuin-A and RBP4 were measured by ELISA. Lipoprotein subfractions were distributed by Lipoprint gelelectrophoresis. RESULTS: Serum fetuin-A and RBP4 were unexpectedly lower in obese patients (p < 0.01 and p < 0.01, respectively) compared to controls and correlated with each other (r = 0.37; p < 0.001). Fetuin-A had positive correlations with HDL-C (r = 0.22; p = 0.02), apolipoprotein AI (apoAI) (r = 0.33; p < 0.001), very-low density lipoprotein (VLDL) subfraction (r = 0.18; p = 0.05), and large HDL subfraction levels (r = 0.3; p = 0.001) but did not show correlation with carbohydrate parameters in all subjects. RBP4 correlated positively with HDL-C (r = 0.2; p = 0.025), apoAI (r = 0.23; p = 0.01), VLDL subfraction (r = 0.37; p < 0.001), intermediate HDL subfraction (r = 0.23; p = 0.01), and small HDL subfraction (r = 0.21; p = 0.02) concentrations, as well as C-peptide levels in overall participants. Backward stepwise multiple regression analysis showed that serum fetuin-A concentration is best predicted by RBP4 and large HDL subfraction. In model 2, VLDL subfraction was the independent predictor of serum RBP4 level. CONCLUSIONS: Our data may indicate a potential role of fetuin-A and RBP4 in impaired lipoprotein metabolism associated with obesity.

Effects of alpha-lipoic acid treatment on serum progranulin levels and inflammatory markers in diabetic neuropathy.

OBJECTIVES: Progranulin (PGRN) is a secreted growth factor that helps to regulate neuronal survival by blocking tumor necrosis factor-alpha (TNFα) receptors. The antioxidant alpha-lipoic acid (ALA) is used in diabetic neuropathy to improve nerve conduction and relieve neuropathic pain, but its effects on PGRN levels have not yet been elucidated. METHODS: In this prospective study, 54 patients with type 2 diabetes and peripheral neuropathy received 600 mg of ALA daily for 6 months. Twenty-four patients with diabetes without neuropathy were also included in the study. Serum PGRN and TNFα levels were determined using enzyme-linked immunosorbent assays. In addition, current perception threshold (CPT) testing was used to assess sensory neuropathy. RESULTS: After ALA treatment, serum PGRN levels were significantly increased and CPT values were significantly improved. Furthermore, there were significant positive correlations among TNFα, ICAM-1, and PGRN levels both before and after ALA treatment. A significant negative correlation was observed between the improvements in CPT and the PGRN levels. Furthermore, ICAM-1 levels were an independent predictor of PGRN levels. CONCLUSIONS: Changes in serum PGRN levels indicate that ALA treatment may have beneficial effects on endothelial function and neuronal inflammation.

Changes in serum afamin and vitamin E levels after selective LDL apheresis.

BACKGROUND: Afamin is a plasma vitamin E-binding glycoprotein partially associated with ApoA1-containing high-density lipoprotein (HDL) subfractions. In a previous study, the serum vitamin E decreased after low-density lipoprotein (LDL) apheresis, while vitamin E/cholesterol ratio increased. We aimed to study the effect of LDL apheresis on serum afamin level. METHODS: The serum level of afamin and oxidized LDL were measured by enzyme-linked immunosorbent assay in six severe heterozygous FH patients before and after their first LDL apheresis treatments and in seven healthy controls. We also investigated the changes in total cholesterol, LDL-C, HDL-C, ApoB, ApoA1, HDL subfractions, and α- and γ-tocopherol levels during the treatment. HDL subfractions were detected by an electrophoretic method on polyacrylamide gel (Lipoprint). Serum α- and γ-tocopherol levels were detected by gas chromatography-mass spectrometry. RESULTS: The first treatment sessions decreased serum afamin levels by an average of 9.4%. Total cholesterol, LDL-C, HDL-C and ApoA1 levels decreased by 52.6; 61.8; 10.5; and 14.1%, respectively. We found that α- and γ-tocopherol levels markedly decreased (by 34.1 and 32.9%, respectively), while α- tocopherol/cholesterol and γ-tocopherol/cholesterol ratios significantly increased (by 41.4 and 40.3%, respectively). Oxidized LDL levels significantly decreased. There was a shift toward the larger HDL subfractions. CONCLUSION: LDL apheresis moderately decreases the circulating levels of afamin parallel to lowering HDL-C and ApoA1 levels. Tocopherol levels decreases markedly compared to afamin levels, however, beneficial changes in vitamin E/cholesterol ratios, oxidized LDL levels and HDL subfraction distribution were detected. These additional effects of LDL apheresis may result in further cardiovascular risk reduction in FH patients.

Serum obestatin level strongly correlates with lipoprotein subfractions in non-diabetic obese patients.

BACKGROUND: Obestatin is a ghrelin-associated peptide, derived from preproghrelin. Although many of its effects are unclear, accumulating evidence supports positive actions on both metabolism and cardiovascular function. To date, level of obestatin and its correlations to the lipid subfractions in non-diabetic obese (NDO) patients have not been investigated. METHODS: Fifty NDO patients (BMI: 41.96 ± 8.6 kg/m2) and thirty-two normal-weight, age- and gender-matched healthy controls (BMI: 24.16 ± 3.3 kg/m2) were enrolled into our study. Obestatin level was measured by ELISA. Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) subfractions, intermediate density lipoprotein (IDL) and very low-density lipoprotein (VLDL) levels and mean LDL size were detected by nongradient polyacrylamide gel electrophoresis (Lipoprint). RESULTS: Serum level of obestatin was significantly lower in NDO patients compared to controls (3.01 ± 0.5 vs. 3.29 ± 0.6 µg/ml, p < 0.05). We found significant negative correlations between the level of obestatin and BMI (r = - 0.33; p < 0.001), level of serum glucose (r = - 0.27, p < 0.05), HbA1c (r = - 0.38; p < 0.001) and insulin (r = - 0.34; p < 0.05). Significant positive correlation was found between obestatin level and the levels of ApoA1 (r = 0.25; p < 0.05), large HDL subfraction ratio and level (r = 0.23; p < 0.05 and r = 0.24; p < 0.05), IDL (r = 0.25 p < 0.05) and mean LDL size (r = 0.25; p < 0.05). Serum VLDL ratio and level negatively correlated with obestatin (r = - 0.32; p < 0.01 and r = - 0.21; p = 0.05). In multiple regression analysis obestatin was predicted only by VLDL level. CONCLUSIONS: Based on our data, measurement of obestatin level in obesity may contribute to understand the interplay between gastrointestinal hormone secretion and metabolic alterations in obesity.

[The role of apolipoprotein M and sphingosine 1-phosphate axis in the prevention of atherosclerosis]. / Az apolipoprotein M és a szfingozin-1-foszfát tengely jelentosége az érelmeszesedés kialakulásának gátlásában.

Previous studies showed that plasma levels of high-density lipoprotein (HDL) cholesterol are inversely related to risk of cardiovascular diseases. However, in the last few decades it became obvious that beyond its plasma level, HDL structure and function have a critical role in its anti-atherogenic efficacy. Apolipoprotein M (ApoM) is an HDL-associated plasma protein affecting HDL metabolism and exhibits various anti-atherosclerotic functions, such as protection against oxidation and regulation of cholesterol efflux. Sphingosine 1-phosphate (S1P) is a potent sphingolipid mediator that regulates numerous cellular responses including cell differentiation and migration, apoptosis and vascular inflammation. The majority of S1P is associated to ApoM containing HDL particles. Therefore, ApoM and S1P content of HDL have an impact on the atherosclerotic process. Moreover, HDL-ApoM and S1P content can be altered in several pathologic conditions such as coronary artery disease. This review covers the currently available data on the contribution of ApoM and S1P to HDL function in health and cardiovascular diseases. Orv Hetil. 2018; 159(5): 168-175.

Alteration of the irisin-brain-derived neurotrophic factor axis contributes to disturbance of mood in COPD patients.

COPD is accompanied by limited physical activity, worse quality of life, and increased prevalence of depression. A possible link between COPD and depression may be irisin, a myokine, expression of which in the skeletal muscle and brain positively correlates with physical activity. Irisin enhances the synthesis of brain-derived neurotrophic factor (BDNF), a neurotrophin involved in reward-related processes. Thus, we hypothesized that mood disturbances accompanying COPD are reflected by the changes in the irisin-BDNF axis. Case history, routine laboratory parameters, serum irisin and BDNF levels, pulmonary function, and disease-specific quality of life, measured by St George's Respiratory Questionnaire (SGRQ), were determined in a cohort of COPD patients (n=74). Simple and then multiple linear regression were used to evaluate the data. We found that mood disturbances are associated with lower serum irisin levels (SGRQ's Impacts score and reciprocal of irisin showed a strong positive association; ß: 419.97; 95% confidence interval [CI]: 204.31, 635.63; P<0.001). This association was even stronger among patients in the lower 50% of BDNF levels (ß: 434.11; 95% CI: 166.17, 702.05; P=0.002), while it became weaker for patients in the higher 50% of BDNF concentrations (ß: 373.49; 95% CI: -74.91, 821.88; P=0.1). These results suggest that irisin exerts beneficial effect on mood in COPD patients, possibly by inducing the expression of BDNF in brain areas associated with reward-related processes involved in by depression. Future interventional studies targeting the irisin-BDNF axis (eg, endurance training) are needed to further support this notion.

Paraoxonase-1 and myeloperoxidase correlate with vascular biomarkers in overweight patients with newly diagnosed untreated hyperlipidaemia.

BACKGROUND: In hyperlipidaemic state, increased levels of myeloperoxidase (MPO) and decreased paraoxonase-1 (PON1) activity have been reported; however, their relationships with other atherosclerotic biomarkers have not been completely clarified. PATIENTS AND METHODS: Serum concentrations of lipid and inflammatory parameters, MPO levels, and PON1 activities were investigated in 167 untreated hyperlipidaemic patients with and without vascular complications and in 32 healthy controls. Additionally, levels of CD40 ligand (sCD40L) and asymmetric dimethyl arginine (ADMA), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1, and oxidized LDL were determined. RESULTS: We found elevated C-reactive protein (CRP), ADMA, sCD40L, sICAM-1 concentrations, and higher MPO levels in patients with vascular complications compared to those without. The PON1 arylesterase activity correlated negatively with sCD40L, ADMA, and sICAM-1 levels, respectively. In contrast, MPO concentrations showed positive correlations with sCD40L, ADMA, and sICAM-1 levels, respectively. CONCLUSIONS: It can therefore be stated that PON1 activity and MPO level correlate strongly with the vascular biomarkers, highlighting the importance of the HDL-associated pro- and antioxidant enzymes in the development of endothelial dysfunction and atherogenesis.

Paraoxonase-1 arylesterase activity is an independent predictor of myeloperoxidase levels in overweight patients with or without cardiovascular complications.

OBJECTIVES: Myeloperoxidase (MPO), matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) were shown to contribute to atherogenesis, while human paraoxonase-1 (PON1) protects against oxidative stress. Although several studies investigated these biomarkers, their associations have not been completely clarified yet. We aimed to investigate these parameters in overweight hyperlipidemic, lipid-lowering therapy-naive patients (n=167) with and without vascular complications. DESIGN AND METHODS: MPO, MMP-9 and TIMP-1 levels were measured by ELISA. PON1 activities were detected spectrophotometrically. PON1 phenotype was calculated by using a dual substrate method. RESULTS: Patients with vascular complications (VC) had significantly higher MPO and TIMP-1 levels compared to those without (patients with no vascular complications; NVC) (728 (367.25-1177.90) mg/ml vs. 315.9 (176.05-687.40) mg/ml; p<0.001; and 172.7 (157.7-197.7) ng/ml vs. 152.6 (129.3-172.3) ng/ml; p<0.0001; respectively). MPO levels showed a significant negative correlation with PON1 arylesterase activity (whole patient group (W): r=0.42, p<0.0001; VC: r=0.44, p=0.01; NVC: r=0.39, p<0.0001) and positive correlations with MMP-9 (W: r=0.37, p<0.0001; VC: r=0.29, p=0.07; NVC: r=0.42, p<0.0001) and TIMP-1 (W: r=0.42, p<0.0001; VC: r=0.33, p<0.05; NVC: r=0.41, p<0.0001), respectively. PON1 arylesterase activity was found to be an independent predictor of MPO levels in the whole patient group (ß=-0.350, p<0.0001) or when studied separately in the subgroups with or without cardiovascular complications (VC: ß=-0.57, p<0.05; NVC: ß=-0.33, p<0.0001). CONCLUSIONS: Our results suggest that parallel investigation of MPO, MMP-9 and TIMP-1 levels and PON1 arylesterase activity may be a more accurate indicator of atherosclerosis, which may allow earlier treatment and therefore, improvement of treatment efficacy.