Influence of Omega-3 Fatty acid status on the way rats adapt to chronic restraint stress.
PLoS ONE. 2012-07-30; 7(7): e42142
DOI: 10.1371/journal.pone.0042142
Lire sur PubMed
Hennebelle M(1), Balasse L, Latour A, Champeil-Potokar G, Denis S, Lavialle M,
Gisquet-Verrier P, Denis I, Vancassel S.
Author information:
(1)INRA, Unité de Nutrition et Régulation Lipidiques des Fonctions Cérébrales,
NuRéLiCe, UR909, Domaine de Vilvert, Jouy en Josas, France.
Omega-3 fatty acids are important for several neuronal and cognitive functions.
Altered omega-3 fatty acid status has been implicated in reduced resistance to
stress and mood disorders. We therefore evaluated the effects of repeated
restraint stress (6 h/day for 21 days) on adult rats fed omega-3 deficient,
control or omega-3 enriched diets from conception. We measured body weight,
plasma corticosterone and hippocampus glucocorticoid receptors and correlated
these data with emotional and depression-like behaviour assessed by their
open-field (OF) activity, anxiety in the elevated-plus maze (EPM), the sucrose
preference test and the startle response. We also determined their plasma and
brain membrane lipid profiles by gas chromatography. Repeated restraint stress
caused rats fed a control diet to lose weight. Their plasma corticosterone
increased and they showed moderate behavioural changes, with increases only in
grooming (OF test) and entries into the open arms (EPM). Rats fed the omega-3
enriched diet had a lower stress-induced weight loss and plasma corticosterone
peak, and reduced grooming. Rats chronically lacking omega-3 fatty acid
exhibited an increased startle response, a stress-induced decrease in locomotor
activity and exaggerated grooming. The brain omega-3 fatty acids increased as
the dietary omega-3 fatty acids increased; diets containing preformed long-chain
omega-3 fatty acid were better than diets containing the precursor
alpha-linolenic acid. However, the restraint stress reduced the amounts of
omega-3 incorporated. These data showed that the response to chronic restraint
stress was modulated by the omega-3 fatty acid supply, a dietary deficiency was
deleterious while enrichment protecting against stress.
Conflict of interest statement: Competing Interests: Unilever provided funding
for supplying research reagents and a grant for Marie Hennebelle, graduate
student. This does not alter the authors′ adherence to all the PLoS ONE policies
on sharing data and materials.