Effects of krill oil containing n-3 polyunsaturated fatty acids in phospholipid form on human brain function: a randomized controlled trial in healthy elderly volunteers

Abstract

BackgroundKrill oil, rich in n-3 (omega-3) polyunsaturated fatty acids (PUFAs) incorporated in phosphatidylcholine, has been reported to have many effects on physiological function. However, there are few studies using psychophysiological methods published that describe the effects of krill oil on brain function. We investigated the influence of ingestion of krill oil on cognitive function in elderly subjects by using near-infrared spectroscopy and electroencephalography.MethodsA randomized, double-blind, parallel-group comparative study design was adopted. Forty-five healthy elderly males aged 61–72 years were assigned to receive 12 weeks of treatment with: medium-chain triglycerides as placebo; krill oil, which is rich in n-3 PUFAs incorporated in phosphatidylcholine; or sardine oil, which is abundant in n-3 PUFAs incorporated in triglycerides. Changes in oxyhemoglobin concentrations in the cerebral cortex during memory and calculation tasks were measured. The P300 component of event-related potentials was also measured during a working memory task.ResultsDuring the working memory task, changes in oxyhemoglobin concentrations in the krill oil and sardine oil groups were significantly greater than those in the medium-chain triglyceride group at week 12. The differential value for P300 latency in the krill oil group was significantly lower than that in the medium-chain triglyceride group at week 12. With regard to the calculation task, changes in oxyhemoglobin concentrations in the krill oil group were significantly greater than those in the medium-chain triglyceride group at week 12.ConclusionThis study provides evidence that n-3 PUFAs activate cognitive function in the elderly. This is especially the case with krill oil, in which the majority of n-3 PUFAs are incorporated into phosphatidylcholine, causing it to be more effective than sardine oil, in which n-3 PUFAs are present as triglycerides.

Low Doses of Long-chain Polyunsaturated Fatty Acids Affect Cognitive Function in Elderly Japanese Men: A Randomized Controlled Trial

“…The efficacy of LCPUFA on P300 amplitude, a secondary outcome, was not observed in the present study. Supplementation of 240 mg/day of ARA was effective on P300 amplitude 14 , but no effects on P300 amplitude were observed with 491 mg/day of EPA and 251 mg/day of DHA or EPA 193 mg/day and DHA 92 mg/day containing phospholipids 25 . Although further studies are needed, the effect of LCPUFA on P300 amplitude might be limited.…”

“…The importance of ARA is consistent with the report indicating that ARA was effective on P300 components in healthy elderly 14,26 . On the other hand, another study showed that EPA 193 mg/day and DHA 92 mg/day containing phospholipids supplementation for 12 weeks improved the P300 latency in elderly Japanese 25 . However, this efficacy was considered to be caused by the unique combination of EPA and phospholipids, because these doses of EPA and DHA were too low to increase blood EPA and DHA levels.…”

“…While high doses 0.9-2.5 g/day of DHA/EPA supplementation improved cognitive function in healthy elderly 11 13 , low doses 0.3-0.7 g/day of DHA/EPA did not affect it 25, 35 38 . In terms of the P300 components, improve P300 components 25 . Although the dose of LCPUFA 300 mg/day of DHA, 100 mg/day of EPA, 120 mg/ day of ARA used in the present study was much lower than the effective doses reported previously, a significant effect was observed in P300 latency.…”

“…P300 latency is prolonged and P300 amplitude is generally decreased with aging 23,24 , suggesting that P300 measurements can be used to evaluate cognitive function in healthy elderly participants. Studies have reported that the supplementation with 240 mg/day ARAcontaining oil improved P300 latency and amplitude 14 , while sardine oil, including 491 mg/day of EPA and 251 mg/ day of DHA, did not influence P300 components in elderly Japanese men 25 . Thus using P300 measurement is considered suitable for the evaluation of cognitive function in healthy elderly participants.…”

Fatty acids and astaxanthin composition of two edible native Mexican crayfish <em>Cambarellus (C.) montezumae</em> and <em>Procambarus (M.) bouvieri</em>

“…The physiological functions of this fat-soluble antioxidant have been widely documented in vitro, in vivo, and in pre-clinical studies and covered extensively for its health benefits in a recent review (Dose et al, 2016). AST associated to EPA and DHA has been demonstrated to have a great effectiveness for improving human brain function (Konagai et al, 2013), and neuro-protection (Barros et al, 2014). In this respect, Saw et al (2013), confirmed that low doses of AST combined with DHA or EPA have a synergistic antioxidant action mediated by the Nrf2 signaling pathway.…”