RESUMO
El consumo crónico de alcohol en Uruguay es un problema creciente, sin embargo, las determinaciones de biomarcadores consensuados no se realizan sistemáticamente ni se investigan otros marcadores potenciales. Para validar la hipótesis de que las metaloproteinasas de matriz con actividad gelatinasa son biomarcadores de consumo crónico de alcohol, se evaluaron muestras de sangre de 100 alcohólicos que comenzaron a atenderse en la Unidad de Trastornos Relacionados con el Alcohol y de 50 donantes sanos no alcohólicos. Las muestras de alcohólicos presentaron actividad de gelatinasas que triplicaron la de los controles y aumentos pequeños pero significativos en los niveles de γ-glutamil transferasa, aspartato-aminotransferasa y volumen corpuscular medio. Los valores de transferrina deficiente en carbohidratos fueron menores en alcohólicos que en controles. Estos resultados permiten proponer a las gelatinasas como los indicadores más sensibles del consumo sostenido de alcohol en la población analizada, ya que las enzimas hepáticas y el volumen corpuscular medio muestran una tendencia acorde con la literatura pero no alcanzaron valores asociados a la patología. Dado que la transferrina deficiente en carbohidratos es considerada el biomarcador indirecto más sensible y específico de consumo crónico de alcohol, los valores menores obtenidos en alcohólicos respecto de controles sugieren problemas metodológicos que podrían subsanarse aplicando otras técnicas de medida o por la presencia de interferencias que deben ser identificadas. Finalmente, estos hallazgos justifican una extensión de este trabajo piloto, así como estudios adicionales centrados en la participación de las metaloproteinasas de matriz con actividad gelatinasa en las cascadas de daño asociadas al consumo crónico de alcohol.
Chronic alcohol consumption in Uruguay is a growing problem, however, determinations of consensual biomarker are not performed systematically neither potential markers are explored. To validate the hypothesis that matrix metalloproteinases with gelatinase activity are biomarkers of chronic alcohol consumption, blood samples of 100 alcoholics that began medical treatment at the Unidad de Trastornos Relacionados con el Alcohol and 50 healthy non-alcoholic donors were evaluated. Alcoholic samples showed gelatinase activity that tripled that of controls and small but significant increases in levels of γ-glutamyl transferase, aspartate-aminotransferase and mean cellular volume. Carbohydrate deficient transferrin values were lower in alcoholics than in controls. These results allow proposing gelatinases as the most sensitive indicators of sustained alcohol consumption in the population analyzed since hepatic enzymes and mean cellular volume showed a tendency consistent with the literature but did not reach values associated with the pathology. Since carbohydrate-deficient transferrin is considered the most sensitive and specific indirect biomarker of chronic alcohol consumption, lower values in alcoholics related to controls suggest methodological problems that could be solved by applying other measurement techniques or by the presence of yet unknown interferences. Finally, these findings justify an extension of this pilot work, as well as additional studies focused on the participation of matrix metalloproteinases with gelatinase activity in the cascades of damage associated with chronic alcohol consumption.
O consumo crônico de álcool no Uruguai é um problema crescente, no entanto, as determinações consensuais de biomarcadores não são realizadas sistematicamente ou os potenciais marcadores são explorados. Para validar a hipótese de que as metaloproteinases de matriz com atividade gelatinase são biomarcadores do consumo crônico de álcool, foram avaliadas amostras de sangue cd 100 alcoólatras que começaram a ser tratadas na Unidad de Trastornos Relacionados con el Alcohol e 50 doadores não-alcoólatras saudáveis. As amostras alcoólicas apresentaram atividade de gelatinase que triplicou a dos controles e pequenos más significativos aumentos nos níveis de γ-glutamil transferase, aspartato-aminotransferase e volume médio celular. Os valores de transferrina deficientes em carboidratos foram menores nos alcoolistas que nos controles. Esses resultados permitem que as gelatinases sejam propostas como os indicadores mais sensíveis do consumo sustentado de álcool na população analisada, uma vez que as enzimas hepáticas e o volume celular médio apresentam uma tendência consistente com a literatura, mas não alcançaram valores associados à patologia. Como a transferrina deficiente em carboidratos é considerada o biomarcador indireto mais sensível e específico do consumo crônico de álcool, os valores mais baixos em alcoólatras do que em controles sugerem problemas metodológicos que poderiam ser sanados pela aplicação de outras técnicas de mensuração pela presença de interferências que deben ser identificadas. Finalmente, esses achados justificam uma extensão deste trabalho piloto, bem como estudos adicionais voltados para a participação de metaloproteinases de matriz com atividade de gelatinase nas cascatas de danos associados ao consumo crônico de álcool.
Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Alcoolismo/diagnóstico , Aspartato Aminotransferases/sangue , Biomarcadores/sangue , Estudos de Casos e Controles , Método Duplo-Cego , Estudos Transversais , Estudos de Coortes , Sensibilidade e Especificidade , Alcoolismo/enzimologia , Alcoolismo/sangue , Índices de Eritrócitos , gama-Glutamiltransferase/sangueRESUMO
BACKGROUND: Pseudomonas aeruginosa is an important human pathogen that causes severe infections in a wide range of immunosuppressed patients. Herein, we evaluated the proteolytic profiles of 96 Brazilian clinical isolates of P. aeruginosa recovered from diverse anatomical sites. METHODS: Cell-associated and extracellular proteases were evidenced by gelatin-SDS-PAGE and by the cleavage of soluble gelatin. Elastase was measured by using the peptide substrate N-succinyl-Ala-Ala-Ala-p-nitroanilide. The prevalence of elastase genes (lasA and lasB) was evaluated by PCR. RESULTS: Bacterial extracts were initially applied on gelatin-SDS-PAGE and the results revealed four distinct zymographic profiles as follows: profile I (composed by bands of 145, 118 and 50kDa), profile II (118 and 50kDa), profile III (145kDa) and profile IV (118kDa). All the proteolytic enzymes were inhibited by EDTA, identifying them as metalloproteases. The profile I was the most detected in both cellular (79.2%) and extracellular (84.4%) extracts. Overall, gelatinase and elastase activities measured in the spent culture media were significantly higher (around 2-fold) compared to the cellular extracts and the production level varied according to the site of bacterial isolation. For instance, tracheal secretion isolates produced elevated amount of gelatinase and elastase measured in both cellular and extracellular extracts. The prevalence of elastase genes revealed that 100% isolates were lasB-positive and 85.42% lasA-positive. Some positive/negative correlations were showed concerning the production of gelatinase, elastase, isolation site and antimicrobial susceptibility. CONCLUSION: The protease production was highly heterogeneous in Brazilian clinical isolates of P. aeruginosa, which corroborates the genomic/metabolic versatility of this pathogen.