Characterization of oxidative stress biomarkers in a freshwater anomuran crab / Caracterização de biomarcadores de estresse oxidativo em caranguejos anomuros de água doce

Abstract In general, environmental responses at level of populations or communities are preceded by alterations at lower biological levels which can be efficiently detected by the analysis of biomarkers. We analyzed the oxidative biomarkers TBARS and Catalase in Aegla singularis, a freshwater crustacean highly sensitive to environmental changes. The objective was to address if are differences in these biomarkers related to the gender as well if they are influenced by seasonal or water physicochemical variables. The results showed differences in biomarkers profile related to the gender. In female crabs were not sensitive to seasonal variations throughout the study period. However, in males the biomarkers evaluated were higher in the winter as compared to remaining seasons and showed tendency of negative correlation with water temperature and pH. This study highlights that gender, seasonal variations and physicochemical variables can influence oxidative stress biomarkers in A. singularis. Female crabs probably are better suited as a model for biomarker application in environmental studies, because their insensibility to seasonal variations can facilitate the observations of responses related specifically to environmental disturbances.

Resumo Em geral, as respostas ambientais ao nível de populações ou comunidades são precedidas pelas alterações nos níveis biológicos inferiores que podem ser eficientemente detectados pela análise de biomarcadores. Neste trabalho, foram analisados os biomarcadores oxidativos TBARS e Catalase em Aegla singularis, um crustáceo de água doce altamente sensível às mudanças ambientais. O objetivo foi investigar se há diferenças nestes biomarcadores relacionados com o gênero, bem como se eles são influenciados por parâmetros sazonais ou físico-químicos. Os resultados mostraram diferenças no perfil de biomarcadores relacionados com o gênero. Caranguejos fêmeas não foram sensíveis a variações sazonais ao longo do período de estudo. Nos machos, os biomarcadores avaliadas apresentaram níveis mais altos no inverno, em comparação com as demais estações e mostraram uma tendência de correlação negativa com a temperatura e pH da água. Este estudo destaca que o sexo, variações sazonais e variáveis físico-químicas podem influenciar os biomarcadores de estresse oxidativo em A. singularis. As fêmeas de A. singularis provavelmente são mais adequadas como um modelo para aplicação destes biomarcadores em estudos ambientais, uma vez que sua insensibilidade às variações sazonais podem facilitar as observações das respostas relacionadas especificamente com perturbações ambientais.

Characterization of oxidative stress biomarkers in a freshwater anomuran crab.

In general, environmental responses at level of populations or communities are preceded by alterations at lower biological levels which can be efficiently detected by the analysis of biomarkers. We analyzed the oxidative biomarkers TBARS and Catalase in Aegla singularis, a freshwater crustacean highly sensitive to environmental changes. The objective was to address if are differences in these biomarkers related to the gender as well if they are influenced by seasonal or water physicochemical variables. The results showed differences in biomarkers profile related to the gender. In female crabs were not sensitive to seasonal variations throughout the study period. However, in males the biomarkers evaluated were higher in the winter as compared to remaining seasons and showed tendency of negative correlation with water temperature and pH. This study highlights that gender, seasonal variations and physicochemical variables can influence oxidative stress biomarkers in A. singularis. Female crabs probably are better suited as a model for biomarker application in environmental studies, because their insensibility to seasonal variations can facilitate the observations of responses related specifically to environmental disturbances.

Characterization of oxidative stress biomarkers in a freshwater anomuran crab

Abstract In general, environmental responses at level of populations or communities are preceded by alterations at lower biological levels which can be efficiently detected by the analysis of biomarkers. We analyzed the oxidative biomarkers TBARS and Catalase in Aegla singularis, a freshwater crustacean highly sensitive to environmental changes. The objective was to address if are differences in these biomarkers related to the gender as well if they are influenced by seasonal or water physicochemical variables. The results showed differences in biomarkers profile related to the gender. In female crabs were not sensitive to seasonal variations throughout the study period. However, in males the biomarkers evaluated were higher in the winter as compared to remaining seasons and showed tendency of negative correlation with water temperature and pH. This study highlights that gender, seasonal variations and physicochemical variables can influence oxidative stress biomarkers in A. singularis. Female crabs probably are better suited as a model for biomarker application in environmental studies, because their insensibility to seasonal variations can facilitate the observations of responses related specifically to environmental disturbances.

Resumo Em geral, as respostas ambientais ao nível de populações ou comunidades são precedidas pelas alterações nos níveis biológicos inferiores que podem ser eficientemente detectados pela análise de biomarcadores. Neste trabalho, foram analisados os biomarcadores oxidativos TBARS e Catalase em Aegla singularis, um crustáceo de água doce altamente sensível às mudanças ambientais. O objetivo foi investigar se há diferenças nestes biomarcadores relacionados com o gênero, bem como se eles são influenciados por parâmetros sazonais ou físico-químicos. Os resultados mostraram diferenças no perfil de biomarcadores relacionados com o gênero. Caranguejos fêmeas não foram sensíveis a variações sazonais ao longo do período de estudo. Nos machos, os biomarcadores avaliadas apresentaram níveis mais altos no inverno, em comparação com as demais estações e mostraram uma tendência de correlação negativa com a temperatura e pH da água. Este estudo destaca que o sexo, variações sazonais e variáveis físico-químicas podem influenciar os biomarcadores de estresse oxidativo em A. singularis. As fêmeas de A. singularis provavelmente são mais adequadas como um modelo para aplicação destes biomarcadores em estudos ambientais, uma vez que sua insensibilidade às variações sazonais podem facilitar as observações das respostas relacionadas especificamente com perturbações ambientais.

CCK-4-induced anxiety but not panic is associated with serum brain-derived neurotrophic factor in healthy subjects.

Recent animal studies consistently confirm the involvement of brain-derived neurotrophic factor (BDNF) in the regulation of anxiety-related behaviours. The role of BDNF in human anxiety has been less investigated. The aim of our study was to examine the association between serum BDNF levels and panic/anxiety responses to cholecystokinin-tetrapeptide (CCK-4) challenge in healthy subjects. BDNF concentrations were detected in serum samples of 37 male and female volunteers before and 120 min after CCK-4 injection. The baseline levels of serum BDNF did not predict the occurrence of CCK-4-induced panic attacks or intensity of panic symptoms and did not significantly change 2 h after the challenge. BDNF serum concentrations 120 min after provocation did not differentiate panickers from non-panickers; however, the subjects reporting stronger anxiety response showed higher levels of BDNF than those with mild anxiety. The anxiety net increase on the Visual Analogue Scale, but not severity of panic symptoms, significantly and positively correlated with the change in BDNF concentration from baseline values. This is the first challenge study to demonstrate a possible impact of BDNF on human anxiety. Our findings suggest a general involvement of BDNF in the regulation of anxiety rather than a specific role of BDNF in disposition to panic attacks.