Cysteine and related aminothiols in cardiovascular disease, obesity and insulin resistance.

Cysteine, homocysteine, glutathione and cysteinylglycine are metabolically related low molecular weight aminothiols involved in antioxidant defense and in thiol redox control in many cellular and extracellular processes. Alterations in plasma aminothiol profiles are evident in pathologic conditions associated with oxidative stress and accordingly can be considered potential biomarkers. More recently, cysteine has received special attention on this regard and several methodologies for the separation and measurement of cysteine as well as other related aminothiols have been developed and refined.

Circulating antioxidant vitamins and copper in Azorean coronary artery disease patients under preventive medication - A case study.

Background And Aim: Oxidative stress and inflammation are conditions that are deeply involved in atherosclerosis and consequent coronary artery disease (CAD). Therefore, the aim of this study was to assess the relationship among circulating antioxidant vitamins (C, A, E), copper, and other pro- or antioxidant/inflammation markers in patients with and without CAD under preventive medication.

Subjects And Methods: 174 Azorean subjects symptomatic for CAD (age 56 ± 9y; 68 % men) submitted to coronary angiography were split into 2 groups: one formed by CAD patients (≥50 % stenosis in at least one major coronary vessel) and the other by non-CAD patients (<50 % stenosis).

Rapid, sensitive and simultaneous determination of ascorbic and uric acids in human plasma by ion-exclusion HPLC-UV.

Objectives: Ascorbic (AA) and uric (UA) acids act as antioxidants and are capable to react with biologically relevant oxidants. We aimed to developed a simple, rapid, sensitive, and accurate ion-exclusion HPLC-UV methodology for the simultaneously determination of AA and UA in human plasma.

Methods: Analytical pre-requisites, such as the use of heparin as an anticoagulant and meta-phosphoric acid as a stabilizer were added for accurate and reliable measurements.

Methodology for a rapid and simultaneous determination of total cysteine, homocysteine, cysteinylglycine and glutathione in plasma by isocratic RP-HPLC.

Alterations in the plasma aminothiols levels can be considered as important biomarkers for the diagnosis and screening of several human disorders, namely cardiovascular diseases. We aimed to optimize a rapid, sensitive and accurate RP-HPLC methodology with fluorescence detection, for the simultaneous determination of the total concentrations of cysteine, homocysteine, cysteinylglycine and glutathione in blood plasma, as well as its application to the evaluation of those thiols levels in plasma of a group of Azorean subjects. Aminothiols were reduced with tri-n-butylphosphine and derivatized with a thiol-specific fluorogenic reagent ammonium 7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate.

Cross-sectional study of risk factors for atherosclerosis in the Azorean population.

Background: Atherosclerosis-a major cause of vascular disease, including ischemic heart disease (IHD), is a pathology that has a two-fold higher mortality rate in the Azorean Islands compared to mainland Portugal.

Aim: This cross-sectional study investigated the role of genetic variation in the prevalence of atherosclerosis in this population.

Subjects And Methods: A total of 305 individuals were characterized for polymorphisms in eight susceptibility genes for atherosclerosis: ACE, PAI1, NOS3, LTA, FGB, ITGB3, PON1 and APOE.

Influence of dyslipidemia and smoking on redox markers in humans--a critical study.

Unlabelled: Experimental research indicates that oxidative processes play a role in susceptibility to a large number of diseases. A better understanding of the parameters affecting redox balance could delay and even prevent such processes.

Objective: The present study aims to investigate blood parameters associated with antioxidant systems in a Portuguese population for the first time, taking into consideration gender, age range, lipid profile and smoking habits as influencing factors.

Polymorphism of the APOE locus in the Azores Islands (Portugal).

Our aim in this study is to report on the polymorphism of the APOE gene in the Azores Islands (Portugal) to obtain a population baseline of the existing variation in this locus, known to be one of the genetic determinants of plasma lipid levels. One hundred twenty-six Azorean individuals were typed for the APOE polymorphism using standard PCR-RFLP. Allele frequencies obtained for APOE*2, APOE*3, and APOE*4 were 6.