Behaviour of carbonyl groups in several clinical conditions: Analysis of our survey.

Protein carbonylation is a marker of oxidative protein damage, that is likely involved in the pathogenesis of several diseases. The aim of this study was to evaluate the protein carbonyl (PC) groups in different clinical conditions. It included different groups of subjects: 81 trained subjects; 23 subjects with mild essential hypertension; 31 middle-aged subjects with metabolic syndrome (MS); 106 subjects with MS not selected for age (subdivided into two subgroups, with and without diabetes mellitus); 91 obese adults subdivided in two subgroups (BMI 30-35 Kg/m2 and BMI > 35 kg/m2); 48 subjects with obstructive sleep apnea syndrome (OSAS) subdivided in accordance with the apnea/hypopnea index (AHI); 27 subjects with chronic kidney disease (CKD) on conservative therapy; 31 subjects with CKD on haemodialysis treatment; and 50 subjects with juvenile myocardial infarction. PC groups were reduced in trained subjects in comparison with sedentary controls, while no variation was observed in mild essential hypertension. PC groups were increased in MS subjects and in adult obese subjects. In MS subjects the PC groups were not influenced by the presence of diabetes mellitus and in adult obese subjects were not influenced by the obesity degree. In OSAS subjects only those with AHI > 30 showed an increase of PC groups. PC groups increased in CKD subjects undergoing conservative treatment and haemodialysis therapy. In dialyzed subjects, after a standard dialysis session, there was a marked increase in PC groups. In juvenile myocardial infarction PC groups were higher than in controls; there was no difference between STEMI and NSTEMI and their concentration was unaffected by the number of cardiovascular risk factors or stenosed coronary vessels.

Lipid Peroxidation, Protein Oxidation, Gelatinases, and Their Inhibitors in a Group of Adults with Obesity.

The association between obesity and cardiovascular diseases has a multifactorial pathogenesis, including the synthesis of inflammatory molecules, the increase in oxidative stress and the dysregulation of the matrix metalloprotease (MMP) concentration and activity. In a group of adults with obesity, divided in 2 subgroups according to the body mass index (BMI), we examined lipid peroxidation, expressed as thiobarbituric acid-reactive substances (TBARS), protein oxidation, expressed as protein carbonyl groups (PCs), plasma gelatinases (MMP-2 and MMP-9), and their tissue inhibitors (TIMP-1 and TIMP-2). In the whole group, as well as in the 2 subgroups (with BMI 30-35 or BMI>35) of obese subjects, we observed an increase in TBARS, PCs, MMP-2, and MMP-9, and also TIMP-1 and TIMP-2 in comparison with the control group. A positive correlation between TBARS and PCs emerged in obese subjects and persisted after dividing obese subjects according to BMI. The correlation between MMP-2 and TIMP-2 was not statistically significant, while a significant correlation was present between MMP-9 and TIMP-1. The correlations between the markers of oxidative stress (TBARS and PCs) and those of the MMP/TIMP profile indicated a more marked influence of protein oxidation on MMPs and TIMPs in comparison with TBARS. The innovative aspect of our study was the simultaneous evaluation of oxidative stress markers and MMP/TIMP profile in adult obese subjects. We observed significant alterations and correlations that may negatively influence the clinical course of the disease.

Gelatinases and their tissue inhibitors in a group of subjects with obstructive sleep apnea syndrome.

Obstructive sleep apnea syndrome (OSAS) is associated with an elevated risk of cardiovascular events and stroke. Matrix metalloproteinases (MMPs) are endopeptidases involved in extracellular matrix degradation and then in the development and progression of cardiovascular diseases. Our aim was to evaluate plasma levels of gelatinases (MMP-2 and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2) in a group of subjects with OSAS. We enrolled 48 subjects (36 men and 12 women; mean age 49.7 ± 14.68 yrs) with OSAS diagnosed with a 1-night cardiorespiratory study and then we subdivided these subjects into two subgroups according to the apnea/hypopnea index (AHI): Low (L = 21 subjects with AHI <30) and High (H = 27 subjects with AHI >30). We measured plasma concentration of the gelatinases and their inhibitors using ELISA kits. We observed a significant increase in plasma concentration of MMP-9, MMP-2, TIMP-1 and TIMP-2 in the entire group of OSAS subjects and in the two subgroups, with higher levels in the H in comparison with the L subgroup. In the whole group of OSAS subjects we also noted a significant decrease in MMP-9/TIMP-1 ratio in comparison with normal controls. Only MMP-9 was significantly correlated with the severity of the disease, expressed as AHI, with the oxygen desaturation index and also with the mean oxygen saturation. MMPs pattern is altered in OSAS and significantly influenced by the severity of the disease; it probably contributes to the vascular remodeling that leads to the atherosclerotic disease and cardiovascular complications.

Nitric oxide metabolites and erythrocyte deformability in a group of subjects with obstructive sleep apnea syndrome.

Our aim was to evaluate nitric oxide metabolites (nitrite and nitrate), expressed as NOx, and erythrocyte deformability, expressed as elongation index, in a group of subjects with obstructive sleep apnea syndrome (OSAS). We enrolled 48 subjects (36 men and 12 women; mean age 50.3±14.68 yrs) with OSAS diagnosed after a 1-night cardiorespiratory sleep study. OSAS severity was assessed evaluating the apnea/hypopnea index (AHI) and subjects were subdivided in two subgroups: Low (L=AHI<30) and High (H=AHI>30). NOx was examined converting nitrate into nitrite with a nitrate reductase and then assessing nitrite with spectrophotometry after the addition of Griess reagent. The elongation index was obtained using the diffractometer Rheodyn SSD of Myrenne at shear stresses of 30 and 60 Pa and it was expressed as elongation index (EI). We found no difference in NOx among the entire group of OSAS subjects and normal controls, while we observed a NOx decrease in the H subgroup in comparison with L subgroup, but not in comparison with normal controls. We noted a significant decrease in EI at each shear stress in the entire group and also in the two subgroups in comparison with controls. The decrease in NO bioavailability and in erythrocyte deformability might contribute to explain the increased cardiovascular risk in OSAS subjects.

Relationships between maximal oxygen uptake and endothelial function in healthy male adults: a preliminary study.

Aerobic capacity, as indicated by maximal oxygen uptake (VO2 max) has an important role in contrasting the traditional cardiovascular risk factors and preventing cardiovascular morbidity and mortality. It is known that endothelial function, measured as flow-mediated dilation (FMD) of the brachial artery, is strictly linked to atherogenesis and cardiovascular risk. However, the relationship between VO2 max and FMD has not been fully investigated especially in healthy non-obese subjects. This preliminary study cross-sectionally investigated the relationship between VO2 max and FMD in 22 non-obese, healthy sedentary male subjects. Dividing the cohort in two subgroups of 11 subjects each according to the median value of VO2 max, the FMD was significantly lower in the subgroup with lower VO2 max (mean ± sem: 7.1 ± 0.7 vs. 9.5 ± 0.8 %; P = 0.035). Absolute VO2 max (mL min(-1)) was significantly and independently correlated with body fat mass (r = -0.50; P = 0.018) and with FMD (r = 0.44; P = 0.039). This preliminary study suggests that maximal oxygen uptake is independently correlated with endothelial function in healthy non-obese adults. These results are also in agreement with the possibility that improving maximal oxygen uptake may have a favorable effect on endothelial function and vice versa.

Erythrocyte deformability and nitric oxide metabolites in athletes before and after a cardiopulmonary test.

OBJECTIVE: To evaluate erythrocyte deformability, nitric oxide metabolites, and their modifications induced by exercise in athletes who practised different sports. DESIGN: This evaluation was effected before and after cardiopulmonary test, using a cycloergometer. SETTING: The study was performed in the Department of Internal Medicine, Cardiovascular and Renal Diseases of the University of Palermo. PARTICIPANTS: We enrolled 62 male athletes who practised endurance (n = 23), mixed (n = 20), and power (n = 19) sports and 20 sedentary male subjects as controls. ASSESSMENT OF RISK FACTORS: No subject had diabetes or hypertension or dyslipidemia. Five control subjects and 14 athletes were smokers. MAIN OUTCOME MEASURES: Erythrocyte deformability was examined as elongation index (EI) using a diffractometer. The nitric oxide metabolites (nitrite + nitrate = NOx) were evaluated employing the Griess reagent. RESULTS: In the whole group, an increase in EI and NOx was present. Subdividing the whole group into 3 subgroups, we noted an increase in EI and NOx only in endurance and mixed athletes. The EI before and after the cardiopulmonary test significantly decreased in the whole group and in power athletes but not in endurance and mixed athletes. Before and after the test, NOx did not significantly change in the whole group and in the 3 subgroups. CONCLUSIONS: In athletes who practised endurance and mixed sports, we observed an increase of NOx level and an increase of erythrocyte deformability. The latter did not change after an exercise test in the same subgroups, whereas it decreased in power athletes.

Nitric oxide metabolites (nitrite and nitrate) in young patients with recent acute myocardial infarction.

Nitric oxide (NO) has a role in the pathophysiology of acute and chronic cardiovascular events. We studied the plasma concentration of NO stable end products (nitrite and nitrate--NOx) in 43 patients aged<46 years, with recent acute myocardial infarction (AMI). The evaluation was effected at the initial stage, after 3 and 12 months. We subdivided the patients into subgroups according to the number of the main cardiovascular risk factors and to the extent of coronary disease. In the whole group the NOx concentration was initially increased and progressively decreased after 3 and 12 months, remaining at both times significantly higher than in control subjects. The patients with more risk factors had a significantly higher NOx concentration. In conclusion, the persisting high NOx concentration in AMI patients is the expression of a prolonged inflammatory condition and is significantly influenced by the simultaneous presence of several cardiovascular risk factors.