RESUMEN
A deficiency of maternal folic acid (FA) can compromise the function and development of the brain, and may produce a susceptibility to diseases such as schizophrenia (SZ) in the later life of offspring. The aim of this study was to evaluate the effects of both FA deficient and FA supplemented diets during gestation and lactation on behavioural parameters, the markers of oxidative stress and neurotrophic factors in adult offspring which had been subjected to an animal model of SZ. Female mother rats (Dam's) were separated into experimental maternal groups, which began receiving a special diet (food) consisting of the AIN-93 diet, a control diet, or an FA deficient diet during the periods of pregnancy and lactation. Dam's receiving the control diet were further subdivided into four groups: one group received only control diet, while three groups to receive supplementation with FA at different doses (5, 10 and 50â¯mg/kg). Adult offspring bred from the Dam's were divided into ten groups for induction of the animal model of SZ through the administration of ketamine (Ket) (25â¯mg/kg). After the last administration of the drug, the animals were subjected to the behavioural tests and were then euthanized. The frontal cortex (FC) and hippocampus (Hip) were then dissected for later biochemical analysis. Our data demonstrates that Ket induced the model of SZ by altering the behavioural parameters (e.g. hyperlocomotion, social impairment, deficits in the sensory-motor profile and memory damage in the adult animals); and also caused changes in the parameters of oxidative stress (lipid hydroperoxide - LPO; 8-isoprostane - 8-ISO; 4-hydroxynonenal - 4-HNE; protein carbonyl content; superoxide dismutase - SOD and catalase - CAT) as well as in the levels of neurotrophic factors (brain-derived neurotrophic factor - BDNF and nerve growth factor - NGF) particularly within the FC of adult offspring. A deficiency in maternal FA, alone or in combination with ket, was able to induce hyperlocomotion and social impairment in the offspring with increased levels of lipid and protein damage (LPO, 8-ISO, 4-HNE, carbonylation of protein) within the FC, increased activity of antioxidant enzymes (SOD and CAT) in both of the brain structures studied, and also reduced the levels of neurotrophins (BDNF and NGF), particularly within the Hip of the adult offspring. Supplementation of FA (5, 10 and 50â¯mg/kg) to the Dam's was mostly able to prevent the cognitive damage which was induced by Ket in the adult animals. FA (10 and 50â¯mg/kg) attenuated the action of Ket in the animals in relation to the biochemical parameters, proving the possible neuroprotective effect of FA in the adulthood of offspring that were subjected to the animal model of SZ. Our study indicates that the intake of maternal FA during pregnancy and lactation plays an important role, particularly in the regulation of markers of oxidative stress and neurotrophins.
Asunto(s)
Conducta Animal , Encéfalo/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Estrés Oxidativo , Esquizofrenia/metabolismo , Animales , Conducta Animal/fisiología , Encéfalo/crecimiento & desarrollo , Suplementos Dietéticos , Modelos Animales de Enfermedad , Femenino , Ácido Fólico/administración & dosificación , Deficiencia de Ácido Fólico , Ketamina , Masculino , Estrés Oxidativo/fisiología , Embarazo , Efectos Tardíos de la Exposición Prenatal , Distribución Aleatoria , Ratas Wistar , Psicología del EsquizofrénicoRESUMEN
Supplementation with omega-3 has been identified as an adjunctive alternative for the treatment of psychiatric disorders, in order to minimize symptoms. Considering the lack of understanding concerning the pathophysiology of schizophrenia, the present study hypothesized that omega 3 prevents the onset of symptoms similar to schizophrenia in young Wistar rats submitted to ketamine treatment. Moreover, the role of oxidative stress in this model was assessed. Omega-3 (0.8g/kg) or vehicle was given by orogastric gavage once daily. Both treatments were performed during 21days, starting at the 30th day of life in young rats. After 14days of treatment with omega-3 or vehicle, a concomitant treatment with saline or ketamine (25mg/kg ip daily) was started and maintained until the last day of the experiment. We evaluated the pre-pulse inhibition of the startle reflex, activity of antioxidant systems and damage to proteins and lipids. Our results demonstrate that supplementation of omega-3 prevented: decreased inhibition of startle reflex, damage to lipids in the hippocampus and striatum and damage to proteins in the prefrontal cortex. Furthermore, these changes are associated with decreased GPx in brain tissues evaluated. Together, our results suggest the prophylactic role of omega-3 against the outcome of symptoms associated with schizophrenia.