[Persistence of oxidative stress after heart transplantation: a comparative study of patients with heart transplant versus chronic stable heart failure]. / Persistencia del estrés oxidativo postrasplante cardíaco: estudio comparativo entre pacientes con trasplante cardíaco y con insuficiencia cardíaca crónica estable.

INTRODUCTION AND OBJECTIVE: Chronic heart failure (CHF) is associated with oxidative stress. Heart transplantation, an important therapeutic alternative in these patients, could reduce oxidative stress by improving cardiac function. Our aim was to evaluate post-heart transplantation oxidative stress. PATIENTS AND METHOD: We studied three experimental groups: a) heart transplant recipients without evidence of rejection (n = 11); b) NYHA class III CHF patients (n = 19), and c) healthy control subjects (n = 14). Oxidative stress was assessed by measuring plasma malondialdehyde levels (MDA), and determining the enzymatic activities of glutathione peroxidase (GSH-Px), catalase (CAT), and superoxide dismutase (SOD). RESULTS: The demographic characteristics of the three groups were similar. Mean time from transplantation was 20.0 4.8 months. Mean MDA plasma levels in heart transplantation and CHF patients were significantly higher than in normal subjects (3.35 0.8; 3.27 1.7 y 0.9 0.3 microM, respectively). GSH-Px activity increased after transplantation compared to control subjects (0.40 0.06 and 0.33 0.05 U/g Hb, respectively), but not the CHF group. A significant decrease in SOD activity was found in the heart transplant vs. CHF group (0.44 0.1 vs. 0.87 0.6 U/mg Hb). There were no differences in CAT values between heart transplant and CHF patients. CONCLUSION: These findings demonstrated the presence of permanent oxidative stress in patients who have undergone heart transplantation, characterized by an increase in MDA and a decrease in SOD activity, despite an increase in GSH-Px activity.

Persistencia del estrés oxidativo postrasplante cardíaco: estudio comparativo entre pacientes con trasplante cardíaco y con insuficiencia cardíaca crónica estable / Persistence of oxidative stress after heart transplantation: a comparative study of patients with heart transplant versus chronic stable heart failure

Introducción y objetivo. Existe estrés oxidativo en pacientes con insuficiencia cardíaca crónica (ICC). El trasplante cardíaco, alternativa terapéutica importante en estos pacientes, podría disminuir el estrés oxidativo al mejorar la función cardíaca. Nuestro objetivo fue evaluar el estrés oxidativo postrasplante cardíaco.Pacientes y método. Fueron estudiados 3 grupos experimentales: a) trasplantados cardíacos, sin evidencia de rechazo (n = 11); b) pacientes con ICC capacidad funcional III de la NYHA (n = 19), y c) sujetos controles sanos (n = 14). El estrés oxidativo se evaluó determinando valores plasmáticos de malondialdehído (MDA), y actividades de glutatión peroxidasa (GSH-Px), catalasa (CAT) y superóxido dismutasa (SOD).Resultados. Las características demográficas fueron similares entre los grupos. El tiempo postrasplante fue 20,0 ñ 4,8 meses. Los valores de MDA en trasplantados y con ICC fueron significativamente mayores que en sujetos normales (3,35 ñ 0,8; 3,27 ñ 1,7, y 0,90 ñ 0,3 µM, respectivamente). La actividad de GSH-Px aumentó en trasplantados respecto al grupo control (0,40 ñ 0,07 y 0,33 ñ 0,05 U/g Hb, respectivamente). La actividad de SOD fue menor en trasplantados respecto al grupo control ICC (0,44 ñ 0,1 frente a 0,87 ñ 0,6 U/mg Hb). No hubo diferencias en las actividades de CAT entre trasplantados y pacientes con ICC.Conclusión. Los pacientes sometidos a trasplante cardíaco tienen un aumento del estrés oxidativo, evidenciado por una elevación del MDA y por una disminución de la actividad de SOD, a pesar de una mayor actividad de GSH-Px. Este aumento del estrés oxidativo fue similar al encontrado en pacientes con ICC estable CF III de la NYHA, y se observó en ausencia de episodios reconocidos de infección o rechazo (AU)

Oxidative stress after reperfusion with primary coronary angioplasty: lack of effect of glucose-insulin-potassium infusion.

OBJECTIVE: To evaluate the oxidative stress status and the modification with glucose-insulin-potassium (GIK) therapy in patients with acute myocardial infarction undergoing primary percutaneous transluminal coronary angioplasty. DESIGN: Prospective, randomized, double-blinded, placebo-controlled study. SETTING: Cardiac intensive care unit at the university hospital. PATIENTS: Twenty patients were randomized to GIK solution (30% glucose in water with insulin 50 IU/L, and KCl 40 mM) vs. placebo (normal saline) at 1.5 mL/kg/hr for 24 hrs. The control group was 15 healthy volunteers with no heart disease. INTERVENTIONS: Eligible patients were randomized by a blinded pharmacist, patients with acute myocardial infarction were treated by primary percutaneous transluminal coronary angioplasty and randomized to GIK or placebo (saline solution). Primary angioplasty was successful in nine of ten patients (90%) and ten of ten patients (100%) in the GIK and placebo groups, respectively. Nine (100%) and six (60%) patients from GIK and placebo groups, respectively, underwent stent implantation. MEASUREMENTS AND MAIN RESULTS: We determined plasma levels of lipid peroxidation estimated by the malondialdehyde assay, superoxide dismutase, glutathione peroxidase, and catalase erythrocyte activities at admission and 0.5 and 24 hrs after angioplasty. Baseline determinations were compared with a control group (n = 15). Baseline clinical characteristics and time to treatment (4.5 +/- 3.5 hrs) were similar between groups. Angioplasty success rate (Thrombolysis in Myocardial Infarction [TIMI] 3 flow with residual stenosis < or = 30%) was 90% and 100% in GIK and placebo groups, respectively. Patients with acute myocardial infarction had an increase of malondialdehyde at baseline (2.9 +/- 1.7 vs. 1.1 +/- 0.3 microM, p <.01) and lower enzymatic activities of superoxide dismutase (0.5 +/- 0.5 vs. 1.3 +/- 0.4 U/mg hemoglobin, p <.01) and catalase (147 +/- 73 vs. 198 +/- 31 U/g hemoglobin, p <.01). These measurements did not change significantly after angioplasty and no differences were observed between GIK and placebo groups. CONCLUSION: Patients with acute myocardial infarction had increased levels of oxidative stress associated with a reduction in enzymatic antioxidant reserve. Administration of GIK solution did not improve these abnormalities among patients undergoing primary angioplasty.