| Background: The endocannabinoid system (ECS) overactivation, associated with increased inflammatory process,
may act as a risk factor for coronary artery disease (CAD). Dietary fat may influence the ECS tone. The aim of the
present study was to investigate the effect of flaxseed oil on the erythrocyte membrane fatty acid profile and ECS
activity by the measurement of serum N-arachydonoil ethanolamine (AEA) and cannabinoid receptor type-1 (CB1),
cannabinoid receptor type-2 (CB2), and fatty acid amide hydrolase (FAAH) mRNA expression.
Methods: This clinical trial was performed on 44 patients with CAD. The intervention group received 1.5% fat milk
supplemented with flaxseed oil (containing 2.5 g α-linolenic acid or ALA), while the placebo group received 1.5%
fat milk for 10 weeks. The fatty acid profile of erythrocyte membrane phospholipids was measured by gas
chromatography. The AEA level was determined using an ELISA kit, and real-time PCR was performed to measure
CB1, CB2, and FAAH mRNA expression pre- and post-intervention.
Results: Flaxseed oil supplementation resulted in a significant increase in the ALA content and a significant
reduction in linoleic acid (LA) content of membrane phospholipids, compared to the placebo group (MD = − 0.35
and 2.89, respectively; P < 0.05). The within group analysis showed that flaxseed oil supplementation caused a
significant reduction in both LA and arachidonic acid (MD = − 4.84 and − 4.03, respectively; P < 0.05) and an
elevation in the ALA (MD = 0.37, P < 0.001) content of membrane phospholipids compared with the baseline. In
the intervention group, a marked reduction was observed in the serum AEA level after 10 weeks of intervention,
compared with the placebo group (MD = 0.64, P = 0.016). Changes in CB2 mRNA expression in the flaxseed oil
group were significant (fold change = 1.30, P = 0.003), compared with the placebo group.
Conclusion: Flaxseed oil supplementation could attenuate the ECS tone by decreasing the AEA level and
increasing CB2 mRNA expression. Therefore, flaxseed oil may be considered a promising agent with
cardioprotective properties. |