British Journal of Nutrition

Table of Contents - 2006 - Volume 95, Issue 02  

Research Article

Interaction of fish oil and a glucocorticoid on metabolic responses to an oral glucose load in healthy human subjects

Jacques Delaruea1 c1, Chang-Hong Lia2, Richard Cohena3, Charlotte Corporeaua1 and Brigitte Simona4

a1 Equipe d'Accueil 948 ‘Oxylipides’, Laboratoire Régional de Nutrition Humaine, Faculté de Médecine de Brest & CHU, F-29 200 Brest, France

a2 Jeune Equipe 313 ‘Lipides et Croissance’, Faculté de Médecine, F-37 000 Tours France

a3 Fédération de Biochimie biologie spécialisée immunoanalyse Hôpital Edouard Herriot F-69 000 Lyon France

a4 Equipe d'Accueil 948 ‘Oxylipides’ Faculté de Médecine de Brest F-29 200 Brest France

Abstract

Compared with saturated fat, n-3 long-chain PUFA-rich fish oil improves insulin sensitivity in rats. We studied whether n-3 long-chain PUFA could prevent insulin resistance induced by dexamethasone (a glucocorticoid) in healthy human volunteers. A group of eight subjects was studied twice after a 2d dexamethasone treatment, before and after a 3-week supplementation with fish oil (providing daily doses of 1·1g 20:5n-3 and 0·7g 22:6n-3). The subjects were studied during the basal state and over the 6h following an oral glucose load (1g/kg). Plasma glucose fluxes were traced with [6,6-2H2]glucose and [13C]glucose (naturally 13C-enriched corn glucose). Substrate oxidation was obtained from indirect calorimetry. Following fish oil supplementation, plasma glucose fluxes and substrate oxidation were maintained despite a 17% reduction (P<0·05) in the area under the curve of plasma insulin response, suggesting an insulin-sensitizing effect.

(Received April 07 2005)

(Revised September 11 2005)

(Accepted September 21 2005)

Key Words:

Correspondence:

c1 *corresponding author: Professor Jacques Delarue, fax +33 2 98 34 78 82, email jacques.delarue@univ-brest.fr

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