RESUMO
Nitric oxide is involved in normal physiological functions and also in pathological processes leading to tissue damage due, in part, to its free radical nature (oxidative stress). Oxidative stress and vascular dysfunction have been recognized as contributing factors in the pathogenesis of Alzheimer disease (AD) and vascular dementia (VD). In order to study the possible links between these processes and dementia, we have analysed plasma amyloid-beta(1-42) levels (Abeta) and total nitric oxide (NOx), apolipoprotein E (ApoE), lipids, vitamin B12, and folate concentrations in the serum of 99 patients with dementia and 55 age-matched non-demented controls. Both nitrate and nitrite levels were measured by a colorimetric method using Griess Reagent and plasma Abeta levels were analysed by a hypersensitive ELISA method. Our data showed a significant decrease of serum NOx levels in dementia, especially in probable AD and VD patients, as compared with controls. We observed a weak correlation between serum NOx levels and cognitive deterioration in dementia; however, NOx levels were not associated with ApoE and Abeta levels. In dementia and controls, a similar correlation pattern between HDL-cholesterol versus NOx was found. No apparent association between NOx, Abeta and AD-related genes [APOE (apolipoprotein E), PSEN1 (Presenilin 1)] was observed. Our data suggest that NOx may contribute to the pathogenesis of dementia through a process mediated by HDL-cholesterol.
Assuntos
Demência/sangue , Óxido Nítrico/sangue , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/sangue , Apolipoproteínas E/sangue , HDL-Colesterol/sangue , Demência/genética , Demência Vascular/sangue , Demência Vascular/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Ácido Fólico/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Oxirredução , Vitamina B 12/sangueRESUMO
The potential effects of Cerebrolysin (EBEWE Pharma, Unterach, Austria), a peptide preparation with neurotrophic activity, on brain bioelectrical activity, cognitive performance and clinical outcome in postacute traumatic brain injury (TBI) patients, were investigated in an exploratory study. A decrease in slow electroencephalogram (EEG) activity and an increase in fast frequencies were observed after the administration of Cerebrolysin. This EEG-activating effect was not influenced by TBI time course or severity, nor by the chronic treatment with nootropic compounds. Cognitive performance, evaluated with the Syndrome Kurztest test, improved in TBI patients after Cerebrolysin treatment, independent of disease severity, time course or disability. A significant improvement in the patients' clinical outcome, only evident during the first year after brain trauma, was also found following Cerebrolysin infusions. No relevant changes in biological parameters nor drug-related adverse events were observed. These promising preliminary results suggest that Cerebrolysin might be a useful treatment to improve the recovery of patients with traumatic brain damage, and encourage the conduction of confirmatory clinical trials.