RESUMO
Thyroid hormones modulate haemoglobin and reactive oxygen species (ROS) production, leading to antioxidant changes. This study evaluated the antioxidant response to ROS in erythrocytes in hypothyroid and hyperthyroid rats. Wistar rats were divided into four groups: control; hyperthyroid (T4-12 mg 1(-1) in drinking water); sham operated (simulation of thyroidectomy); and hypothyroid (thyroidectomized). Four weeks after, blood was collected and haemoglobin and T(4) levels, lipid peroxidation (LPO), protein oxidation, superoxide dismutase (SOD), catalase (CAT) , glutathione S-transferase (GST) and glutathione peroxidase (GPx) activities, and total radical antioxidant potential (TRAP) were measured. SOD, CAT and GST immunocontent was evaluated. Haemoglobin levels were increased in hyperthyroid erythrocytes. LPO and carbonyls were augmented (65% and 55%, respectively) in hyperthyroid and reduced (31% and 56%, respectively) in hypothyroid group. SOD and CAT activities have not changed, as well as CAT immunocontent. TRAP was diminished in both hyperthyroid and hypothyroid groups (36% and 37%, respectively). GST activity and immunocontent, as well as GPx activity, were increased in hyper and hypothyroid rats. The data suggest that thyroid hormone changes determine ROS concentration changes and decrease of some antioxidant defences that would lead to a compensatory answer of the GST and GPx enzymes, which could be consider as credible biomarkers.
Assuntos
Antioxidantes/metabolismo , Eritrócitos/metabolismo , Hemoglobinas/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Biomarcadores , Proteínas Sanguíneas/metabolismo , Catalase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Hipertireoidismo/metabolismo , Hipotireoidismo/metabolismo , Peroxidação de Lipídeos , Masculino , Oxirredução , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Tiroxina/sangueRESUMO
Role of reactive oxygen species (ROS)/nitric oxide (NO) balance and renin-angiotensin system in mediating cardiac hypertrophy in hyperthyroidism was evaluated in an in vivo and in vitro experimental model. Male Wistar rats were divided into four groups: control, thyroid hormone, vitamin E (or Trolox, its hydrosoluble analogue), thyroid hormone+vitamin E. Angiotensin II receptor (AT1/AT2) gene expression, immunocontent of AT1/AT2 receptors, angiotensinogen, NADPH oxidase (Nox2), and nitric oxide synthase isoforms, as well as ROS concentration (hydrogen peroxide and superoxide anion) were quantified in myocardium. Thyroid hormone increased ROS and NO metabolites, iNOS, nNOS and eNOS isoforms and it was accompanied by cardiac hypertrophy. AT1/AT2 expression and the immunocontent of angiotensinogen and Nox2 were enhanced by thyroid hormone. Antioxidants reduced ROS levels, Nox2, AT1/AT2, NOS isoforms and cardiac hypertrophy. In conclusion, ROS/NO balance may play a role in the control of thyroid hormone-induced cardiac hypertrophy mediated by renin-angiotensin system.
Assuntos
Cardiomegalia/patologia , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sistema Renina-Angiotensina/fisiologia , Hormônios Tireóideos/metabolismo , Angiotensinogênio/análise , Animais , Western Blotting , Cardiomegalia/metabolismo , Células Cultivadas , Cromanos/farmacologia , Hipertireoidismo/metabolismo , Masculino , NADPH Oxidases/análise , Óxido Nítrico/análise , Óxido Nítrico Sintase/genética , Reação em Cadeia da Polimerase , Ratos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptor Tipo 2 de Angiotensina/genética , Receptor Tipo 2 de Angiotensina/metabolismo , Receptores de Angiotensina/genética , Hormônios Tireóideos/farmacologia , Vitamina E/farmacologiaRESUMO
Research on developmental psychopathology has highlighted the role of parental behavior in subsequent development of pathology in children and adolescents. Although parental psychological control has been an area of interest to researchers, the connection between psychological control and anxiety has not been well established. We administered measures of perceived parental control and acceptance (separate forms for mother and father), trait anxiety, and satisfaction with life to 202 undergraduate students. Analysis indicated that perception of parents (both mother and father) as psychologically controlling was significantly positively correlated with trait anxiety and significantly negatively correlated with satisfaction with life. This held even after the effects of psychological control by the other parent were statistically eliminated.
Assuntos
Ansiedade/psicologia , Relações Pais-Filho , Poder Familiar/psicologia , Qualidade de Vida/psicologia , Adulto , Feminino , Humanos , Controle Interno-Externo , Masculino , Estudos RetrospectivosRESUMO
The biosynthesis of the anti-arrhythmic alkaloid ajmaline is catalysed by more than 10 specific enzymes. In this multistep process polyneuridine aldehyde esterase (PNAE) catalyses a central reaction by transforming polyneuridine aldehyde into epi-vellosimine, which is the immediate precursor for the synthesis of the ajmalane skeleton. PNAE was purified from cell suspension cultures of Rauvolfia serpentina. The N-terminal sequence and endoproteinase LysC fragments of the purified protein were used for primer design and for the amplification of specific PCR products leading to the isolation of PNAE-encoding cDNA from a R. serpentina library. The PNAE cDNA was fused with a C-terminal His-tag, expressed in Escherichia coli and purified to homogeneity using Ni-affinity chromatography. The pure enzyme shows extraordinary substrate specificity, completely different to other esterases. Sequence alignments indicate that PNAE is a new member of the alpha/beta hydrolase super family.
