Análise do perfil de aminoácidos em amostras de pacientes com acidente vascular cerebral isquêmico (AVCI)

Abstract

Stroke is the third leading cause of death worldwide, exceeded only by heart disease and cancer, and the leading cause in Brazil. The ischemic stroke (IS) contributes to approximately 87% of the cases and according to the etiology can be classified into five subtypes: atherothrombotic, cardioembolic, lacunar, other etiologies and undetermined etiology (cryptogenic). The identification of specific cause for each patient, early diagnosis and the proper prognosis has important clinical implications, particularly in relation to treatment. The diagnosis of ischemic stroke is based primarily on the patient's history and the use of imaging techniques. Computed tomography (CT) is widely used but little sensitive to acute ischemic stroke. The magnetic resonance imaging (MRI) has high sensitivity and permits the differentiation of the subtypes, but because of the cost is not yet available in most hospitals. Until then, there are no biomarkers of chronic and acute ischemic stroke that can complement clinical and imaging examinations. In this context, we propose to investigate the metabolic profile in samples from patients with ischemic stroke chronic in search of biomarkers in peripheral blood, which may contribute to the pathophysiology of the disease and its diagnosis and prognosis. For the analysis of the metabolic profile investigate the concentration of sixteen amino acids in the plasma of patients with any subtype of ischemic stroke (n = 73) compared to the control group (n = 16), using gas chromatography coupled to mass spectrometry. Combining the results of multivariate statistical analysis obtained by Partial Least Squares-Discriminant Analysis (PLS-DA) and support vector machinesDiscriminant Analysis (SMV-DA) with the amino acid profile found by the Mann-Whitney test, we can infer a metabolic signature for a stroke formed by the amino acids: methionine, alanine, glycine, serine, leucine, proline , phenylalanine and lysine. Each subtype of ischemic stroke also had a characteristic amino acid profile compared to the control and the other subtypes, which may also be considered metabolic signatures. These amino acids categorized these profiles can be considered as potential biomarkers of chronic ischemic stroke.