Associations between myeloperoxidase and paraoxonase-1 and type 2 diabetes in patients with ischemic heart disease.

BACKGROUND: The phrase "dysfunctional high-density lipoprotein" has been developed in the literature to describe the particle which loses its basic role- anti-oxidative and anti-inflammatory activity. In this porcess, the significance of enzymes- pro-oxidant myeloperoxidase (MPO) and antioxidant paraoxonase-1 (PON-1) from the perspective of HDL-C function has been noted. AIMS: The objective of this study was to analyze the associations between two enzymes -MPO and PON-1 and type 2 diabetes (T2DM) in patients with ischemic heart disease (IHD). METHODS: An observational cross-sectional study including 70 patients with IHD of whom 35 had also T2DM, and 35 had no T2DM. Laboratory tests (MPO, PON-1, fasting glucose, glycated hemoglobin, total cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, and high-sensitivity C-reactive protein) were performed. RESULTS: The study revealed a significant difference in the serum concentration of the enzymes between patients with IHD with and without T2DM. Our results showed increased MPO concentration levels in diabetic patients. The analysis also revealed that T2DM is independently associated with an increase in MPO levels. Simultaneously, a decrease in PON-1 levels was observed in patients with T2DM. The study also revealed that T2DM is independently associated with a decrease in PON-1 levels. CONCLUSIONS: In patients with type 2 diabetes the profile of enzymes involved in high-density lipoprotein metabolism in patients with IHD is worse than in patients without T2DM. The increase in the levels of MPO, an enzyme with oxidative and atherogenic properties and on a decrease in PON-1 levels, an enzyme with antioxidant and atheroprotective properties is observed.

High-density lipoprotein (HDL) cholesterol - more complicated than we think?

INTRODUCTION AND OBJECTIVE: There are some clinical situations where a high level of HDL cholesterol (HDL-C) may be unfavourable. In these situations, HDL-C may undergo some changes, and even if its quantity is within the reference range, its quality is no longer the same. BRIEF DESCRIPTION OF STATE OF KNOWLEDGE: Diabetes is the state of elevated oxidative stress. Studies conducted to-date have revealed an increased production of the reactive forms of oxygen as the result of tissue damage in diabetes patients. The expression 'dysfunctional HDL' has been coined in the literature to describe high-density lipoproteins that lose their antioxidative and anti-inflammatory properties, that is, HDL-C that loses its basic functions. Recent observational studies have confirmed that the atheroprotective activity of properly functioning HDL-C is frequently impaired in clinical situations associated with oxidative stress. The presented review lays the foundation for a new approach to understanding how the functional properties of HDL help reduce cardiovascular risk. CONCLUSIONS: In the light of presented findings it seems that there is a need to seek a better diagnostic marker than HDL-C level. This study presents some possible directions for future research to bring us closer to the full understanding of the HDL particle and its role in patients with ischemic heart disease and type 2 diabetes.

Association of serum levels of lipoprotein A-I and lipoprotein A-I/A-II with high on-treatment platelet reactivity in patients with ST-segment elevation myocardial infarction.

OBJECTIVE: High-density lipoproteins (HDLs) are a very heterogeneous group of particles. Little is known about the impact of their subfractions including lipoprotein A-I (LpA-I) and lipoprotein A-I/A-II (LpA-I/A-II) on platelet function and high on-treatment platelet reactivity (HPR), particularly in the acute phase of ST-segment elevation myocardial infarction (STEMI). The aim of the study was to evaluate the relationship between serum levels of LpA-I and LpA-I/A-II and HPR in STEMI patients. METHODS: Fifty-two consecutive STEMI patients (26.9% women, mean age 60.6±9.1 years) were enrolled into this study. Clinical and demographic data were collected and HDL subfractions were measured by rocket immunoelectrophoresis. Platelet reactivity was assessed using light transmission aggregometry and quantitative flow cytometry. RESULTS: We found a positive correlation between platelet aggregation after both ADP-5 and ADP-20 stimulation and serum level of LpA-I. Compared with subjects with satisfactory platelet response to clopidogrel, patients with HPR had 32.44% higher serum level of LpA-I (p=0.021). On the other hand, patients with HPR assessed by ADP-5 stimulation had 22.13% lower serum level of LpA-I/A-II (p=0.040). Regression analysis showed that LpA-I [odds ratio (OR) 1.03; 95% confidence interval (CI) 1-1.07; p=0.049] and current smoking (OR 0.18; 95% CI 0.04-0.81; p=0.025) were independent predictors of HPR. With receiver operating characteristic (ROC) curve analysis, we designated the cut-off point at serum level of 57.52 mg/dL for LpA-I for predicting HPR (AUC=0.71, p=0.010). CONCLUSION: This study showed that higher serum level of LpA-I measured in the acute phase of STEMI is an independent risk factor for HPR. Our study is the first to demonstrate an important and distinct activity of LpA-I and LpA-I/A-II that can prove pleiotropic and different functions of HDL subfractions in acute STEMI.

Life-threatening cardiac manifestations of primary antiphospholipid syndrome.

We report a rare case of primary antiphospholipid syndrome (APS) in a 43-year-old man presenting as recurrent acute coronary stent thrombosis and complicated by three myocardial infarctions. As illustrated in this report, in APS patients recurrent life-threatening arterial thrombotic events may occur in spite of recommended anticoagulant therapy. We conclude that the APS should be considered as a potential cause of acute coronary syndrome, particularly in young individuals with a history of recurrent thrombotic events and/or with abnormal coagulation test results. Further studies are needed to determine the best therapeutic strategy for APS patients with acute coronary syndrome.

[Recurrence of tricuspid regurgitation in a patient with a rheumatic fever after mitral valve implantation with concomitant tricuspid valve annuloplasty]. / Ponowna niedomykalnosc zastawki trójdzielnej u chorej po operacji wszczepienia zastawki mitralnej i jednoczesnej plastyce zastawki trójdzielnej w przebiegu goraczki reumatycznej.

A case of a 62-year-old female with a recurrence of tricuspid regurgitation is presented. This complication occurred after mitral valve implantation and tricuspid valve annuloplasty. Diagnosis and treatment of this condition following rheumatic fever are discussed.