RESUMO
The ingestion of water containing hydrogen sulphide (H(2)S) is common in spring sulphurous mineral water (SMW) therapy. We hypothesized that observed detrimental effects are related to the alteration of erythrocytes metabolism caused by H(2)S. To verify our hypothesis, we treated 20 healthy volunteers with SMW and evidenced an increase of methemoglobin concentration, an inhibition of both erythrocyte glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and glucose-6-phosphate dehydrogenase (G6PDH) activities. To investigate the mechanism of H(2)S effect on GAPDH activity, an in vitro study was performed by incubating both erythrocytes from 12 healthy volunteers and purified GAPDH with buffered [(35)S]-H(2)S labelled sulphurous water. The interaction between H(2)S and NAD(+)(H), was also investigated. The results indicate that a direct reaction between GAPDH and H(2)S does not occur and the observed decrease of GAPDH activity is to ascribe to the reaction between H(2)S and NAD(+)(H). This may lead to GAPDH inhibition by two ways, namely (i) cellular NAD(+)(H) reduced availability and (ii) catalytic site blockage. In conclusion, our results show that among the detrimental effects of SMW administration are erythrocyte GAPDH and G6PDH activity inhibition and increased methemoglobin concentration. A mechanism to explain the occurrence of these biochemical events is also proposed.
Assuntos
Eritrócitos/metabolismo , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/farmacologia , Águas Minerais/análise , Adulto , Regulação Enzimológica da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/antagonistas & inibidores , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Estrutura Molecular , NAD/química , NAD/metabolismo , Niacinamida/farmacologia , Processamento de Proteína Pós-Traducional , Fatores de TempoRESUMO
BACKGROUND: Erythrocyte morphology has already been studied in essential hypertension (EH) and cell membrane alterations have been observed. Relationships among red cell rheological, biochemical, and morphological properties still appear complex and are not clearly understood. METHODS: Erythrocyte morphology study was carried out by using the novel automated method we have recently developed. The morphometric parameters derived from optical microscope images were elaborated with image processing software (NIH Scion Image) to construct an application for the principal component analysis (PCA) to achieve a reliable and objective statistical method that would discriminate among erythrocyte morphologies of the considered groups. Three groups of subjects were studied: healthy (n = 30), healthy with familial EH (n = 25), and EH suffering subjects (n = 26). RESULTS: Our results show that morphological modifications are evident in both erythrocytes from EH and from healthy with familial EH subjects as compared to the controls. PCA showed remarkable morphological alterations in EH patients. In fact, the PCA explains for the 86.271% of the total variance that can be considered an excellent result. CONCLUSIONS: The results suggest that the use of this automated easy and inexpensive method for the detection of cell shape abnormalities is of high value in the early EH prediction.