Altered behavior of adult obese rats by monosodium l-glutamate neonatal treatment is related to hypercorticosteronemia and activation of hypothalamic ERK1 and ERK2.
Nutr Neurosci
; 20(3): 153-160, 2017 Apr.
Article
de En
| MEDLINE
| ID: mdl-25683673
ABSTRACT
OBJECTIVES:
Obesity is a metabolic and hormonal disorder with serious social and psychological impacts. There is a close relationship among obesity, neuroendocrine homeostasis and behavioral patterns. However, few data are available in the literature regarding this subject. This study assessed behavior and memory of adult obese rats by monosodium l-glutamate (MSG) neonatal treatment or highly palatable dietary treatment.METHODS:
MSG obesity was induced by subcutaneous injections of MSG (4 mg/g) during the first 5 days of life (Ob-MSG); control group (C-MSG), received saline solution equimolar. Both groups were fed with commercial chow. To induce dietary obesity, 21-day-old rats were assigned to two experimental diets highly palatable diet (Ob-Diet) and control diet (C-Diet) composed of commercial chow. Ninety-day-old animals were submitted to behavioral assessment by the open-field test and short- and long-term memory by the object recognition test. Biometric variables were obtained, the Lee index was calculated and mass of retroperitoneal and perigonadal fat pads was measured. Furthermore, an altered behavioral profile was investigated by quantification of plasmatic corticosterone, expression, and activity of hypothalamic extracellular signal-regulated kinase protein (ERK) 1 and 2.RESULTS:
Increased Lee index and fat pads were observed in Ob-MSG and Ob-Diet groups. Ob-MSG presented a higher level of anxiety and impaired long-term memory compared to C-MSG, while there was no difference between Ob-Diet and C-Diet. The Ob-MSG group presented a higher level of plasmatic corticosterone and increased phosphorylation of hypothalamic ERK1 and 2.DISCUSSION:
Both treatments induced obesity but only Ob-MSG showed altered behavioral parameters, which is related to increased concentration of corticosterone and hypothalamic ERK1 and 2 activation.Mots clés
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Corticostérone
/
Système de signalisation des MAP kinases
/
Modèles animaux de maladie humaine
/
Consolidation de la mémoire
/
Hypothalamus
/
Neurones
/
Obésité
Type d'étude:
Prognostic_studies
Limites:
Animals
Langue:
En
Journal:
Nutr Neurosci
Sujet du journal:
CIENCIAS DA NUTRICAO
/
NEUROLOGIA
Année:
2017
Type de document:
Article
Pays d'affiliation:
Brésil