July 2016

Abstracts on omega-3s from salmon

1. 1. Anxiolytic-like effect of a salmon phospholipopeptidic complex composed of polyunsaturated fatty acids and bioactive peptides.
      A phospholipopeptidic complex obtained by the enzymatic hydrolysis of salmon heads in green conditions, exert anxiolytic-like effects in a time and dose-dependent manner, with no affection of locomotor activity. This study focused on the physic-chemical properties of the lipidic and peptidic fractions from this natural product. The characterization of mineral composition, amino acid and fatty acids was carried out. Stability of nanoemulsions allowed us to realize a behavioral study conducted with four different tests on 80 mice. This work highlighted the dose dependent effects of the natural complex and its various fractions over a period of 14 days compared to a conventional anxiolytic. The intracellular redox status of neural cells was evaluated in order to determine the free radicals scavenging potential of these products in the central nervous system (CNS), after mice sacrifice. The complex peptidic fraction showed a strong scavenging property and similar results were found for the complex as well as its lipidic fraction. For the first time, the results of this study showed the anxiolytic-like and neuroprotective properties of a phospholipopeptidic complex extracted from salmon head. The applications on anxiety disorders might be relevant, depending on the doses, the fraction used and the chronicity of the supplementation. [Belhaj N, Desor F, Gleizes C, et al. Anxiolytic-like effect of a salmon phospholipopeptidic complex composed of polyunsaturated fatty acids and bioactive peptides. Marine Drug. 2013;11:4294-4317.]
   2. Polar lipids: n-3 PUFA carriers for membranes and the brain: Nutritional interest and emerging processes.
      The n-3 fatty acids are unanimously considered to have high nutritional value, especially the long chain (LC) polyunsaturated fatty acids (PUFA) from marine origin. However, most of the products available in the market contain LC-PUFA extirified on the glycerol under the common form of triglycerols. The study investigates a process by which the PUFA can be esterified on polar lipids, especially phospholipids. The patented process is performed under low temperature without use of solvents and produces a Phospho-Lipo-Peptidic Complex that is particularly rich in DHA and is esterified in the proper sn-2 position on PL. Further, it has been demonstrated that n-3 fatty acids esterified on polar lipids instead of triglycerols, and retained in the proper, natural sn-2 position, have dramatically enhanced gastrointestinal absorption and intracellular incorporation (Bourre 2004). In pharmacokinetically validated CACO-2 studies, n-3 PUFA absorption across the enteric barrier was 5 fold over triglycerol bound n-3 PUFA fish oil. Subsequent intracellular levels were 50 fold greater. Phospholipids themselves have been shown in other studies (Kidd 1999; Bernoud, et al, 1999) to have direct brain impact, especially in the area of memory and learning performances in the aging human. Therefore, a process by which n-3 PUFA can be delivered in the correct sn-2 position and esterified to phospholipids may be a preferred delivery model over n-3 PUFA delivery esterified to triglycerols in fish oil. [Parmentier M, Mahmoud C, Linder M, Fanni J. Polar lipids: n-3 PUFA carriers for membranes and the brain: Nutritional interest and emerging processes. Oléagineux, Corps Gras, Lipides; Volume 14 (Issue 3): p.224-229.]

   ADDITIONAL INFORMATION
   Marine Phospho-Lipo-Peptidic complex for health benefits. In recent years, marine phospholipids represent a new source of n-3 fatty acids, in particular DHA for application in foods, neutraceuticals and cosmetics. According to the commercial terminology marine lecithin is used as a broad definition to describe a mixture of polar lipids (phospholipids and glycolipids) comprising predominantly long chain and highly unsaturated fatty acids obtained from a marine raw material. Phospholipids are major constituents of biological cell membranes. These amphiphilic molecules have a structural and functional synergy with fatty acids. Those are the lipophilic moiety associated with an hydrophilic part in form of a phosphoric acid ester. Phospholipids mainly differ by the group linked to the phosphoric ester (e.g. choline, ethanolamine, inositol, serine, …). The metabolic efficiency of these molecules depends on the type and location of the unsaturation of fatty acids. Marine phospholipids are characterized by very high levels of mostly long chain and highly unsaturated fatty acids mainly eicosapentaenoic and docosahexaenoic acids (C20:5 n-3 and C22:6 n-6, respectively). Docosahexaenoic acid (DHA), the end product of the omega-3 family fatty acid, is an abundant component in the brain phospholipids and a major nutrient of marine lipids. DHA is particularly enriched in the brain, retina, and spermatozoa phospholipids and plays a crucial role in brain development, learning ability, and visual acuity. [Linder M. Marine phosphor-lipo-peptidic complex for health benefits. White paper.]

   Analysis of lipids extracted from salmon (Salmo salar) heads by commercial proteolytic enzymes. Fresh salmon heads were submitted to controlled proteolysis using food-grade commercial enzymes (Alcalase, Neutrase, and Protamex). The release of oil under mild conditions (60°, 2h) compared favourably with organic solvent extraction (1.98% vs. 21.5%). Lipids extracted by solvent and lipids resulting from enzymatic processes displayed a similar content of PUFA (about 35%), mainly eicosapentaenoic acid (EPA; 8.4% vs. 7.7%) and docosahexaenoic acid (DHA; 12.1% vs 11.9%). Thin-layer chromatography (TLC-FID latroscan) showed that the polar lipid fraction accounted for 55% of total lipids (phophatidylethanolamine, 20.7%; phosphatidylcholine, 14.8%). Salmon head phospholipids may be more effective carriers of highly unsaturated fatty acids to specific tissues than triacyglycerols, as shown by their content in EPA (10.3 and 6.9%, respectively) and DHA (33.1 and 9.1%, respectively). [Gbogouri GA, Linder M, Fanni J, Parmentier M. Analysis of lipids extracted from salmon (Salmo salar) heads by commercial proteolytic enzymes. Eur J Lipid Sci Technol. 2006;108:766-775.]

   Doxosahexaenoic acid prevents neuronal apoptosis induced by soluble amyloid-β oligomers. A growing body of evidence supports the notion that soluble oligomers of amyloid-β (Aβ) peptide interact with the neuronal plasma membrane, leading to cell injury and inducing death-signaling pathways that could account for the increased neurodegeneration occurring in Alzheimer’s disease (AD). Doxosahexaenoic acid (DHA, C22:6, n-3) is an essential polyunsaturated fatty acid in the CNS and has been shown in several epidemiological and in vivo studies to have protective effects against AD and cognitive alterations. However, the molecular mechanisms involved remain unknown. We hypothesized that DHA enrichment of plasma membranes could protect neurons from apoptosis induced by soluble Aβ oligomers. DHA pre-treatment was observed to significantly increase neuronal survival upon Aβ treatment by preventing cytoskeleton perturbations, caspase activation and apoptosis, as well as by promoting extracellular signal-related kinase (ERK)-related survival pathways. These data suggest that DHA enrichment probably induced changes in neuronal membrane properties with functional outcomes, thereby increasing protection from soluble Aβ oligomers. Such neuroprotective effects could be of major interest in the prevention of AD and other neurodengenerative diseases. [ Florent S, Malaplate-Armond C, Youssef I, et al. Doxosahexaenoic acid prevents neuronal apoptosis induced by soluble amyloid-β oligomers. J Neurochem. 2006;96:385-395.]