Effect of fish oil on oxidative stress markers in patients with probable Alzheimer´s disease

Abstract

High intake of omega-3 fatty acids has been associated with synaptic plasticity, neurogenesis and memory in several experimental models. To assess the efficacy of fish oil supplementation on oxidative stress markers in patients diagnosed with probable Alzheimer´s disease (AD) we conducted a double blind, randomized, placebo controlled clinical trial. AD patients who met the inclusive criteria were given fish oil (containing 0.45 g eicosapentaenoic acid and 1 g docosahexaenoic acid) or placebo daily for 12 months. Oxidative stress markers [lipoperoxides, nitric oxide catabolites levels, oxidized/reduced glutathione ratio, and membrane fluidity] and fatty acid profile in erythrocytes were assessed at enrollment, and 6 and 12 months after the start of the testing period. At the end of the trial, in patients who received fish oil, we detected a decrease in the omega 6/omega 3 ratio in erythrocyte membrane phospholipids. This change was parallel with decreases in plasma levels of lipoperoxides and nitric oxide catabolites. Conversely, the ratio of reduced to oxidized glutathione was significantly increased. In addition, membrane fluidity was increased significantly in plasma membrane samples. In conclusion fish oil administration has a beneficial effect in decreasing the levels of oxidative stress markers and improving the membrane fluidity in plasma. El alto consumo de ácidos grasos omega-3 se asocia con la plasticidad sináptica, neurogénesis y memoria en varios modelos experimentales. Para evaluar la eficacia de la suplementación con aceite de pescado en los marcadores de estrés oxidativo en pacientes con diagnóstico de la enfermedad de Alzheimer (EA) probable realizamos un ensayo clínico doble ciego, aleatorizado, controlado con placebo. A los pacientes con la EA que cumplían los criterios de inclusión se les administró aceite de pescado (que contenía 0,45 g de ácido eicosapentaenoico y 1 g de ácido docosahexaenoico) o placebo diariamente durante 12 meses. Los marcadores de estrés oxidativo plasmático [niveles de lipoperóxidos y catabolitos del óxido nítrico, cociente de glutatión reducido a glutatiónoxidado) y fluidez de la membrana] y el perfil de ácidos grasos en los eritrocitos se evaluaron al inicio, 6 meses y alos 12 meses. Al final del ensayo, en pacientes que recibieron aceite de pescado detectamos una disminución en el cociente de ácidos grasos omega 6/omega 3 en los fosfolípidos de la membrana eritrocitaria. Este cambio ocurrió en paralelo a la disminución de los niveles plasmáticos de lipoperóxidos y catabolitos del óxido nítrico. Por el contrario, el cociente de glutatión reducido a glutatión oxidado se incrementó significativamente. Además, la fluidez de la membrana aumentó significativamente en las muestras analizadas. En conclusión, la administración de aceite de pescado tiene un efecto beneficioso al disminuir los niveles de marcadores de estrés oxidativo plasmático y mejorar la fluidez de la membrana plasmática.

Combination Therapy for Sustainable Fish Oil Products: Improving Cognitive Function with n-3 PUFA and Natural Ingredients

“…A double-blind RCT investigated the effectiveness of daily FO (0.45 g EPA and 1 g DHA) on AD patients for 12 months. The results demonstrated that FO administration significantly decreased oxidative stress markers and improved the membrane fluidity in plasma [ 92 ]. However, n-3 PUFAs are vulnerable to lipid peroxidation.…”

Diet in the Prevention of Alzheimer’s Disease: Current Knowledge and Future Research Requirements

“…The study by Sanchez-Romero L. et al analyzed people who had Alzheimer’s disease and proved that the consumption of fish oil rich in DHA and EPA is associated with a better condition of the erythrocyte membrane and a decrease in oxidative stress. Additionally, in the MIND diet, whole grains are a source of vegetable protein, and their recommended consumption is at least three servings of whole grains per day [ 129 , 132 , 138 ].…”

Formulation Development of Functional Oil Loaded Rizatriptan Benzoate Microemulsion: An In Vitro and Ex Vivo Insight

“…Several studies revealed that Poly Unsaturated Fatty Acid (PUFA) oils containing ω-3 fatty acids improve neurotransmission [31,32] , synaptic plasticity [33] , membrane fluidity, reduce oxidative stress [34][35][36] , increases nerve growth [37] , increases cerebral flow, decreases inflammatory mediators and their synthesis [38,39] . PUFA rich oils used in various diseases such as Alzheimer disease [40] , Parkinson's disease [41] , schizophrenia [42] , cancer [43] , ischemia [44] , epilepsy [45] , multiple sclerosis [46,47] .…”