title: Different effect of high fat diet and physical exercise in the hippocampal signaling.
abstract: Obesity is an epidemic disease that may affect brain function. The present study examined the effect of high fat diet (HF) and physical exercise on peripheral tissue and hippocampal signaling. CF-1 mice (n = 4, per cage) were divided into groups receiving high fat (HF) or control (CD) diets for 5 months, with or without voluntary exercise. Serum triacylglycerol, total cholesterol, HDLc, liver triacylglycerol and glycogen concentrations were evaluated (n = 6). Also, the phosphorylation state of the AKT --> ERK 1/2 --> CREB pathway (AKT, pAKTser473, ERK 1/2, pERK 1/2, CREB and pCREB, n = 4-6) was analyzed in the hippocampus. HF diet caused an increase in AKT phosphorylation at ser473 (P < 0.05), while exercise increased the phosphorylation of ERK 1/2 (P < 0.05) and CREB (P < 0.05). As expected, exercise reversed some of the harmful effects of HF, i.e., increased liver deposition of fat (P < 0.05) and fat gain in the abdominal region (P < 0.05). In conclusion, the effects of exercise and HF diet on brain signaling appear to affect the hippocampal AKT --> ERK 1/2 --> CREB pathway in independent ways: HF intake caused increased phosphorylation of AKTser473, while exercise increased ERK 1/2 --> CREB signaling. The physiological relevance of these findings in brain function remains to be elucidated.
authors.affiliation: Departamento de Bioquímica, Programa de Pós-Graduação em Ciências Biológicas-Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, Porto Alegre, RS, Brazil.
authors.forename: Alexandre Pastoris
authors.initials: AP
authors.lastname: Muller
authors.forename: Martín
authors.initials: M
authors.lastname: Cammarota
authors.forename: Marcelo de Oliveira
authors.initials: MO
authors.lastname: Dietrich
authors.forename: Liane N
authors.initials: LN
authors.lastname: Rotta
authors.forename: Luis Valmor
authors.initials: LV
authors.lastname: Portela
authors.forename: Diogo Onofre
authors.initials: DO
authors.lastname: Souza
authors.forename: Iván
authors.initials: I
authors.lastname: Izquierdo
authors.forename: Lia R M
authors.initials: LR
authors.lastname: Bevilaqua
authors.forename: Marcos Luiz Santos
authors.initials: ML
authors.lastname: Perry
mesh_terms: D000818:Animals; D001835:Body Weight; D004041:Dietary Fats / Q000008:administration & dosage*; D005951:Glucose Tolerance Test; D006624:Hippocampus / Q000201:enzymology / Q000502:physiology*; D008055:Lipids / Q000097:blood; D008099:Liver / Q000033:anatomy & histology; D020935:MAP Kinase Signaling System; D008297:Male; D051379:Mice; D009929:Organ Size; D010805:Physical Conditioning, Animal; D015398:Signal Transduction
chemical_list: D004041:Dietary Fats; D008055:Lipids