Marine omega-3 phospholipids: metabolism and biological activities

The Food Sources in Western Diets Modulate Obesity Development, Insulin Sensitivity, and the Plasma and Cecal Metabolome in Mice

SCOPE

Dietary constituents modulate development of obesity and type 2 diabetes. The metabolic impact from different food sources in western diets (WD) on obesity development is not fully elucidated. This study aims to identify dietary sources that differentially affect obesity development and the metabolic processes involved.

METHODS AND RESULTS

Mice were fed isocaloric WDs with protein and fat from different food groups, including egg and dairy, terrestrial meat, game meat, marine, vegetarian, and a mixture of all. This study evaluates development of obesity, glucose tolerance, insulin sensitivity, and plasma and cecal metabolome. WD based on marine or vegetarian food sources protects male mice from obesity development and insulin resistance, whereas meat-based diets promote obesity. The intake of different food sources induces marked differences in the lipid-related plasma metabolome, particularly impacting phosphatidylcholines. Fifty-nine lipid-related plasma metabolites are positively associated with adiposity and a distinct cecal metabolome is found in mice fed a marine diet.

CONCLUSION

This study demonstrates differences in obesity development between the food groups. Diet specific metabolomic signatures in plasma and cecum associated with adiposity, where a marine based diet modulates the level of plasma and cecal phosphatidylcholines in addition to preventing obesity development.

Marine Animal Co-Products-How Improving Their Use as Rich Sources of Health-Promoting Lipids Can Foster Sustainability

Marine lipids are recognized for their-health promoting features, mainly for being the primary sources of omega-3 fatty acids, and are therefore critical for human nutrition in an age when the global supply for these nutrients is experiencing an unprecedent pressure due to an ever-increasing demand. The seafood industry originates a considerable yield of co-products worldwide that, while already explored for other purposes, remain mostly undervalued as sustainable sources of healthy lipids, often being explored for low-value oil production. These co-products are especially appealing as lipid sources since, besides the well-known nutritional upside of marine animal fat, which is particularly rich in omega-3 polyunsaturated fatty acids, they also have interesting bioactive properties, which may garner them further interest, not only as food, but also for other high-end applications. Besides the added value that these co-products may represent as valuable lipid sources, there is also the obvious ecological upside of reducing seafood industry waste. In this sense, repurposing these bioresources will contribute to a more sustainable use of marine animal food, reducing the strain on already heavily depleted seafood stocks. Therefore, untapping the potential of marine animal co-products as valuable lipid sources aligns with both health and environmental goals by guaranteeing additional sources of healthy lipids and promoting more eco-conscious practices.

Variations of intact phospholipid compositions in the digestive system of Antarctic krill, Euphausia superba, between summer and autumn

The biochemical composition of Antarctic krill, Euphausia superba, is largely determined by their feeding behaviour. As they supply energy for animals of a higher trophic level and are also commercialized for human consumption, the interest in research on the species is high. Lipids, especially phospholipids, make up a high proportion of dry weight in krill. Seasonal changes are well documented in the fingerprint of free fatty acids analysed after hydrolysis of phospholipids, but the underlying intact polar lipids are rarely considered. In this study, we evaluated the compositions of intact phospholipids (IPLs) in the stomach, digestive gland and hind gut of Antarctic krill caught in summer and autumn at the Antarctic Peninsula region. Using high-resolution mass spectrometry, the fatty acid composition of 179 intact phospholipids could be resolved. Most IPLs were phosphatidylcholines, followed by phosphatidylethanolamines. Several very long chain polyunsaturated fatty acids up to 38:8, which have not been reported in krill before, were identified. The composition shifted to higher molecular weight IPLs with a higher degree of unsaturation for summer samples, especially for samples of the digestive gland. The data supplied in this paper provides new insights into lipid dynamics between summer and autumn usually described by free fatty acid biomarkers.

Cardiovascular Diseases and Marine Oils: A Focus on Omega-3 Polyunsaturated Fatty Acids and Polar Lipids

Cardiovascular diseases (CVD) remain the leading cause of death across the globe, hence, establishing strategies to counteract CVD are imperative to reduce mortality and the burden on health systems. Dietary modification is an effective primary prevention strategy against CVD. Research regarding dietary supplementation has become increasingly popular. This review focuses on the current in vivo, in vitro, and epidemiological studies associated with that of omega-3 polyunsaturated fatty acids (n-3 PUFAs) and polar lipids (PLs) and how they play a role against CVD. Furthermore, this review focuses on the results of several major clinical trials examining n-3 PUFAs regarding both primary and secondary prevention of CVD. Notably, we place a lens on the REDUCE-IT and STRENGTH trials. Finally, supplementation of PLs has recently been suggested as a potential alternative avenue for the reduction of CVD incidence versus neutral forms of n-3 PUFAs. However, the clinical evidence for this argument is currently rather limited. Therefore, we draw on the current literature to suggest future clinical trials for PL supplementation. We conclude that despite conflicting evidence, future human trials must be completed to confirm whether PL supplementation may be more effective than n-3 PUFA supplementation to reduce cardiovascular risk.

Comparison of the Effect of Phospholipid Extracts from Salmon and Silver Carp Heads on High-Fat-Diet-Induced Metabolic Syndrome in C57BL/6J Mice

Metabolic syndrome (MetS) is a global health problem, and EPA/DHA-enriched phospholipids (EPA/DHA-PLs) have been found to have positive effects on MetS improvement. Currently, research on EPA/DHA-PL mainly focuses on special and rare seafood, such as phospholipids derived from krill, sea cucumber, squid, and fish roe. However, it has been recently demonstrated that abundant EPA/DHA-PL can also be found in bulk fish and its by-products. Nonetheless, there is still limited research on the biological activities of EPA/DHA-PL derived from these sources. The aim of this study was to investigate the effect of phospholipid extracts from the heads of salmon and silver carp (S-PLE and SC-PLE) on the high-fat-diet-induced MetS in C57/BL mice. After an 8-week intervention, both SC-PLE and S-PLE had a significant ameliorating effect on MetS. Moreover, SC-PLE was more effective than S-PLE in reducing liver inflammation and fasting glucose. Both of the PL extracts were able to regulate the expression of key genes in lipid synthesis, fatty acid β-oxidation, and insulin signaling pathways. Compared with S-PLE, dietary SC-PLE had a greater influence on liver metabolomics. Pathway enrichment analysis showed that the differential metabolites of SC-PLE were mainly involved in arachidonic acid metabolism and glutathione metabolism. The results indicated that the different metabolic regulation methods of S-PLE and SC-PLE could be related to their variant molecular composition in EPA/DHA-PL.

Potential Benefits of Omega-3 Polyunsaturated Fatty Acids (N3PUFAs) on Cardiovascular Health Associated with COVID-19: An Update for 2023

The accumulating literature demonstrates that omega-3 polyunsaturated fatty acid (n-3 polyunsaturated fatty acid, N3PUFA) can be incorporated into the phospholipid bilayer of cell membranes in the human body to positively affect the cardiovascular system, including improving epithelial function, decreasing coagulopathy, and attenuating uncontrolled inflammatory responses and oxidative stress. Moreover, it has been proven that the N3PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are precursors of some potent endogenous bioactive lipid mediators that mediate some favorable effects attributed to their parent substances. A dose-response relationship between increased EPA and DHA intake and reduced thrombotic outcomes has been reported. The excellent safety profile of dietary N3PUFAs makes them a prospective adjuvant treatment for people exposed to a higher risk of cardiovascular problems associated with COVID-19. This review presented the potential mechanisms that might contribute to the beneficial effects of N3PUFA and the optimal form and dose applied.

Lysophosphatidylcholine-DHA Specifically Induces Cytotoxic Effects of the MDA-MB-231 Human Breast Cancer Cell Line In Vitro-Comparative Effects with Other Lipids Containing DHA

Docosahexaenoic acid (DHA, C22:6 ω-3) is a dietary polyunsaturated fatty acid that has an important role in human health. Epidemiological studies linked a high intake of DHA to a reduced risk of certain cancers. Recently, attention focused on how the lipid carrier in which DHA is delivered, i.e., esterified on acylglycerols, phospholipids, or free, affects its biological effects. However, studies comparing the effects of these different forms for DHA supply to cancer cells in vitro are limited. In this study, the effect of free DHA and five lipids carrying one to three DHA chains (LPC-DHA, PC-DHA, MAG-DHA, DAG-DHA and TAG-DHA) on the viability of the MDA-MB-231 breast cancer cell line was compared. Our results revealed a strong structure-function relationship of DHA-carrying lipids on the viability of MDA-MB-231 cells. Glycerophosphocholine-based lipids are the most effective DHA carriers in reducing the viability of MDA-MB-231 cells, with LPC-DHA being more effective (IC₅₀ = 23.7 µM) than PC-DHA (IC₅₀ = 67 µM). The other tested lipids are less toxic (MAG-DHA, free DHA) or even not toxic (DAG-DHA, TAG-DHA) under our conditions. Investigating the mechanism of cell death induced by LPC-DHA revealed increased oxidative stress and membrane cell damage.

Marine Fish-Derived Lysophosphatidylcholine: Properties, Extraction, Quantification, and Brain Health Application

Long-chain omega-3 fatty acids esterified in lysophosphatidylcholine (LPC-omega-3) are the most bioavailable omega-3 fatty acid form and are considered important for brain health. Lysophosphatidylcholine is a hydrolyzed phospholipid that is generated from the action of either phospholipase PLA1 or PLA2. There are two types of LPC; 1-LPC (where the omega-3 fatty acid at the sn-2 position is acylated) and 2-LPC (where the omega-3 fatty acid at the sn-1 position is acylated). The 2-LPC type is more highly bioavailable to the brain than the 1-LPC type. Given the biological and health aspects of LPC types, it is important to understand the structure, properties, extraction, quantification, functional role, and effect of the processing of LPC. This review examines various aspects involved in the extraction, characterization, and quantification of LPC. Further, the effects of processing methods on LPC and the potential biological roles of LPC in health and wellbeing are discussed. DHA-rich-LysoPLs, including LPC, can be enzymatically produced using lipases and phospholipases from wide microbial strains, and the highest yields were obtained by Lipozyme RM-IM®, Lipozyme TL-IM®, and Novozym 435®. Terrestrial-based phospholipids generally contain lower levels of long-chain omega-3 PUFAs, and therefore, they are considered less effective in providing the same health benefits as marine-based LPC. Processing (e.g., thermal, fermentation, and freezing) reduces the PL in fish. LPC containing omega-3 PUFA, mainly DHA (C22:6 omega-3) and eicosapentaenoic acid EPA (C20:5 omega-3) play important role in brain development and neuronal cell growth. Additionally, they have been implicated in supporting treatment programs for depression and Alzheimer’s. These activities appear to be facilitated by the acute function of a major facilitator superfamily domain-containing protein 2 (Mfsd2a), expressed in BBB endothelium, as a chief transporter for LPC-DHA uptake to the brain. LPC-based delivery systems also provide the opportunity to improve the properties of some bioactive compounds during storage and absorption. Overall, LPCs have great potential for improving brain health, but their safety and potentially negative effects should also be taken into consideration.

Marine-Derived Compounds Applied in Cardiovascular Diseases: Submerged Medicinal Industry

Cardiovascular diseases (CVDs) are among the most impactful illnesses globally. Currently, the available therapeutic option has several side effects, including hypotension, bradycardia, arrhythmia, and alteration in different ion concentrations. Recently, bioactive compounds from natural sources, including plants, microorganisms, and marine creatures, have gained a lot of interest. Marine sources serve as reservoirs for new bioactive metabolites with various pharmacological activities. The marine-derived compound such as omega-3 acid ethyl esters, xyloketal B, asperlin, and saringosterol showed promising results in several CVDs. The present review focuses on marine-derived compounds' cardioprotective potential for hypertension, ischemic heart disease, myocardial infarction, and atherosclerosis. In addition to therapeutic alternatives, the current use of marine-derived components, the future trajectory, and restrictions are also reviewed.

Effects of high temperature and marine heat waves on seagrasses: Is warming affecting the nutritional value of Posidonia oceanica?

Primary producers nutritional content affects the entire food web. Here, changes in nutritional value associated with temperature rise and the occurrence of marine heat waves (MHWs) were explored in the endemic Mediterranean seagrass Posidonia oceanica. The variability of fatty acids (FAs) composition and carbon (C) and nitrogen (N) content were examined during summer 2021 from five Mediterranean sites located at the same latitude but under different thermal environments. The results highlighted a decrease in unsaturated FAs and C/N ratio and an increase of monounsaturated FA (MUFA) and N content when a MHW occurred. By contrast, the leaf biochemical composition seems to be adapted to local water temperature since only few significant changes in MUFA were found and N and C/N had an opposite pattern compared to when a MHW occurs. The projected increase in temperature and frequency of MHW suggest future changes in the nutritional value and palatability of leaves.

Comparative Lipidomics Study of Four Edible Red Seaweeds Based on RPLC-Q-TOF

Red seaweeds (Rhodophyta) are becoming increasingly important as a food and medicine source in blue biotechnology applications such as functional foods, feeds, and pharmaceuticals. Compared to fatty acid composition and sterols, the lipidome in red seaweeds is still in an early disclosure stage. In this study, the lipidomes of four red seaweeds (Gracilaria sjoestedtii, Gracilaria verrucosa, Gelidium amansii, and Chondrus ocellatus) collected from the coastal area in north China were characterized using reversed-phase liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (RPLC-Q-TOF). Hundreds of lipid molecular species including glycolipids, phospholipids, sphingolipids, glycerolipids, and betaine lipids were identified and quantified. Novel lipids with unique molecular structures such as glucuronosyldiacylglycerols (GlcADG), head-group acylated GlcADG (acGlcADG), and hexose-inositol-phosphoceramides (Hex-IPC) were discovered in red seaweeds for the first time, greatly expanding our knowledge on glycolipids and sphingolipids in seaweeds. Glycolipids were the dominant components (45.6-67.7% of total lipids) with a high proportion of polyunsaturated fatty acids (PUFA) including arachidonic acid (AA) and eicosapentaenoic acid (EPA), indicating the potential nutritional value of the four red seaweeds. The investigated red seaweeds showed a distinctive sphingolipid profile with the t18:1 being the predominant LCB in Cer (41.1-71.5%) and HexCer (91.3-97.9%) except for Gelidium amansii, which had the highest proportion of t18:0. Comparison of lipid profiles among the four red seaweeds revealed that AA- and EPA-glycolipids are good lipid markers for the differentiation of red seaweed samples. The AA proportion in glycolipids of Gracilaria genus was much higher than Gelidium genus and Chondrus genus. This study acquired comprehensive lipid profiles from four red seaweeds, revealing the uniqueness of natural biochemical fingerprints of red seaweeds and further promoting their utilization.

Integrated lipidomic and transcriptomic analyses reveal the mechanism of large yellow croaker roe phospholipids on lipid metabolism in normal-diet mice

Large yellow croaker roe phospholipids (LYCRPLs) could regulate the accumulation of triglycerides and blood lipid levels. However, there exists little research on the mechanism of LYCRPLs on lipid metabolism in normal-diet mice. In this work, the mice on a normal diet were given low-dose, medium-dose, and high-dose LYCRPLs by intragastric administration for 6 weeks. At the same time, the physiological and biochemical indicators of the mice were determined, and the histomorphological observation of the liver and epididymal fat was carried out. In addition, we examined the gene expression and lipid metabolites in the liver of mice using transcriptomic and lipidomic and performed a correlation analysis. The results showed that LYCRPLs regulated the lipid metabolism of normal-diet mice by affecting the expression of the glycerolipid metabolism pathway, insulin resistance pathway, and cholesterol metabolism pathway. This study not only elucidated the main pathway by which LYCRPLs regulate lipid metabolism, but also laid a foundation for exploring LYCRPLs as functional food supplements.

Physical and Oxidative Water-in-Oil Emulsion Stability by the Addition of Liposomes from Shrimp Waste Oil with Antioxidant and Anti-Inflammatory Properties

Liposomes made of partially purified phospholipids (PL) from Argentine red shrimp waste oil were loaded with two antioxidant lipid co-extracts (hexane-soluble, Hx and acetone-soluble, Ac) to provide a higher content of omega-3 fatty acids. The physical properties of the liposomes were characterized by Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS) and Differential Scanning Calorimetry (DSC). The antioxidant and anti-inflammatory activity of the lipid extracts and liposomal suspensions were evaluated in terms of Superoxide and ABTS radical scavenging capacities and TNF-α inhibition. Uni-lamellar spherical liposomes (z-average ≈ 145 nm) with strong negative ζ potential (≈ -67 mV) were obtained in all cases. The high content of neutral lipids in the Hx extract caused structural changes in the bilayer membrane and decreased entrapment efficiency regarding astaxanthin and EPA + DHA contents. The liposomes loaded with the Hx/Ac extracts showed higher antioxidant and anti-inflammatory activity compared with empty liposomes. The liposomal dispersions improved the physical and oxidative stability of water-in-oil emulsions as compared with the PL extract, inducing pronounced close packing of water droplets. The liposomes decreased hydroperoxide formation in freshly made emulsions and prevented thio-barbituric acid-reactive substances (TBARS) accumulation during chilled storage. Liposomes from shrimp waste could be valuable nanocarriers and stabilizers in functional food emulsions.

Compositional Study of Phospholipids from the Dried Big Head and Opossum Shrimp, Mussel, and Sea Cucumber Using 31P NMR Spectroscopy: Content and Fatty Acid Composition of Plasmalogen

Herein, we present a qualitative and quantitative analysis of the compositions of plasmalogens and phospholipids (PLs) in dried big head shrimp (Solenocera melantho), opossum shrimp (Neomysis awatschensis), mussel (Mytilus galloprovincialis), and sea cucumber (Apostichopus japonicus). We also analyze the fatty acid composition of the extracted lipids, phosphatidyl choline (PtdCho), and plasmalogen choline (PlsCho) from each sample. In big head shrimp, opossum shrimp, and mussel, phosphatidyl choline (PtdCho) was the most abundant PL at 1677.9, 1603, and 1661.6 mg/100 g of dried sample, respectively, whereas the most abundant PL in sea cucumber was PlsCho (206.9 mg/100 g of dried sample). In all four samples, plasmalogen ethanolamine (PlsEtn) was higher than phosphatidyl ethanolamine (PtdEtn). The content (mg/100 g of dried sample) of PlsCho was highest in mussel (379.0), and it was higher in big head shrimp (262.3) and opossum shrimp (245.6) than sea cucumber (206.9). The contents (mg/100 g of dried sample) of PlsEtn were in the order of mussel (675.4) > big head shrimp (629.5) > opossum shrimp (217.9) > sea cucumber (51.5). For analyzing the fatty acids at the sn-2 position of PlsCho, the consecutive treatment with phospholipase A1, solid phase extraction, thin-layer chromatography (TLC), and GC-FID were applied. The most abundant fatty acid was eicosapentaenoic acid (EPA, C20:5, n-3) in big head shrimp and sea cucumber, palmitoleic acid (C16:1, n-7) in opossum shrimp, and docosadienoic acid (C22:2, n-6) in mussel.

Advances in enzyme biocatalysis for the preparation of functional lipids

Functional lipids, mainly ω-3 polyunsaturated fatty acids (n-3 PUFAs) such as eicosapentaenoic (EPA; 20:5n-3) and docosahexaenoic (DHA; 22:6n-3), are known to have a variety of health benefits. Lipases and phospholipases are widely used to prepare different forms of structured lipids, since biocatalytic methods can be carried out under mild conditions, preserving the quality of the products. On the other hand, many processes still are conducted at high temperatures and with organic solvents, which are conditions unfavorable for the production of nutritional products. This article gives an updated overview of enzyme biocatalysis methods for the preparation of different derivatives containing n-3 PUFAs, including specific reactions, enzyme immobilization research for high-efficiency catalysis, and enzyme engineering technologies (higher selectivity, stability, and activity). Furthermore, advanced control strategies of biocatalytic processes and reactors are presented. The future prospect and opportunities for marine functional lipids are also discussed. Therefore, the obtainment of enzymes endowed with superior properties and the development of optimized processes, still have to be pursued to achieve greener bio-catalyzed processes.

Administration of krill oil extends lifespan of fish Nothobranchius guentheri via enhancement of antioxidant system and suppression of NF-κB pathway

Krill oil (KO) extracted from Antarctic krill (Euphausia superba) mainly comprises phospholipids and triglycerides. KO has been shown to prolong the median lifespan of the nematode Caenorhabditis elegans, but to shorten the lifespan of long-lived F1 mice; therefore, it remains controversial over the life-extending property of KO. In this study, we clearly demonstrated that dietary intake of KO extended both the mean and maximum lifespans of aged male Nothobranchius guentheri (p < 0.05), reduced the accumulation of lipofuscin (LF) (p < 0.05) in the gills and senescence-associated β-galactosidase (SA-β-Gal) (p < 0.05) in the caudal fins, and lowered the levels of protein oxidation (p < 0.05), lipid peroxidation (p < 0.01), and reactive oxygen species (ROS) (p < 0.01) in the muscles and livers, indicating that KO possesses rejuvenation and anti-aging activity. We also showed that KO enhanced the activities of antioxidant enzymes catalase (CAT) (p < 0.05), superoxide dismutase (SOD) (p < 0.05), and glutathione peroxidase (GPX) (p < 0.05) in aged male N. guentheri. In addition, KO administration effectively reversed histological lesions including inflammatory cell infiltration and structural collapse in the muscles and livers of aged N. guentheri and suppressed the nuclear factor kappa-B (NF-κB) signaling pathway (p < 0.05), a master regulator of inflammation. Altogether, our study indicates that KO has anti-aging and rejuvenation property. It also suggests that KO exerts its anti-aging and rejuvenation effects via enhancement of the antioxidant system and suppression of the NF-κB signaling pathway.

Omega-3 phospholipids and obesity-associated NAFLD: Potential mechanisms and therapeutic perspectives

Prevalence of non-alcoholic fatty liver disease (NAFLD) increases in line with obesity and type 2 diabetes, and there is no approved drug therapy. Polyunsaturated fatty acids of n-3 series (omega-3) are known for their hypolipidaemic and anti-inflammatory effects. Existing clinical trials suggest varying effectiveness of triacylglycerol- or ethyl ester-bound omega-3 in the treatment of NAFLD, without affecting advanced stages such as non-alcoholic steatohepatitis. Preclinical studies suggest that the lipid class used to supplement omega-3 may determine the extent and nature of their effects on metabolism. Phospholipids of marine origin represent an alternative source of omega-3. The aim of this review is to summarise the available evidence on the use of omega-3 phospholipids, primarily in obesity-related NAFLD, and to outline perspectives of their use in the prevention/treatment of NAFLD. A PubMed literature search was conducted in May 2021. In total, 1088 articles were identified, but based on selection criteria, 38 original papers were included in the review. Selected articles describing the potential mechanisms of action of omega-3 phospholipids have also been included. Preclinical evidence clearly indicates that omega-3 phospholipids have strong antisteatotic effects in the liver, which are stronger compared to omega-3 administered as triacylglycerols. Multiple mechanisms are likely involved in the overall antisteatotic effects, involving not only the liver but also adipose tissue and the gut. Robust preclinical evidence for strong antisteatotic effects of omega-3 phospholipids in the liver should be confirmed in clinical trials. Further research is needed on the possible effects of omega-3 phospholipids on advanced NAFLD.

Algal Lipids as Modulators of Skin Disease: A Critical Review

The prevalence of inflammatory skin diseases continues to increase with a high incidence in children and adults. These diseases are triggered by environmental factors, such as UV radiation, certain chemical compounds, infectious agents, and in some cases, people with a genetic predisposition. The pathophysiology of inflammatory skin diseases such as psoriasis or atopic dermatitis, but also of skin cancers, is the result of the activation of inflammation-related metabolic pathways and the overproduction of pro-inflammatory cytokines observed in in vitro and in vivo studies. Inflammatory skin diseases are also associated with oxidative stress, overproduction of ROS, and impaired antioxidant defense, which affects the metabolism of immune cells and skin cells (keratinocytes and fibroblasts) in systemic and skin disorders. Lipids from algae have been scarcely applied to modulate skin diseases, but they are well known antioxidant and anti-inflammatory agents. They have shown scavenging activities and can modulate redox homeostasis enzymes. They can also downmodulate key inflammatory signaling pathways and transcription factors such as NF-κB, decreasing the expression of pro-inflammatory mediators. Thus, the exploitation of algae lipids as therapeutical agents for the treatment of inflammatory skin diseases is highly attractive, being critically reviewed in the present work.

Partial Replacement of Dietary Fat with Krill Oil or Coconut Oil Alleviates Dyslipidemia by Partly Modulating Lipid Metabolism in Lipopolysaccharide-Injected Rats on a High-Fat Diet

This study investigated the effects of partial replacement of dietary fat with krill oil (KO) or coconut oil (CO) on dyslipidemia and lipid metabolism in rats fed with a high-fat diet (HFD). Sprague Dawley rats were divided into three groups as follows: HFD, HFD + KO, and HFD + CO. The rats were fed each diet for 10 weeks and then intraperitoneally injected with phosphate-buffered saline (PBS) or lipopolysaccharide (LPS) (1 mg/kg). The KO- and CO-fed rats exhibited lower levels of serum lipids and aspartate aminotransferases than those of the HFD-fed rats. Rats fed with HFD + KO displayed significantly lower hepatic histological scores and hepatic triglyceride (TG) content than rats fed with HFD. The KO supplementation also downregulated the adipogenic gene expression in the liver. When treated with LPS, the HFD + KO and HFD + CO groups reduced the adipocyte size in the epididymal white adipose tissues (EAT) relative to the HFD group. These results suggest that KO and CO could improve lipid metabolism dysfunction.

From process effluents to intestinal health promotion: Developing biopolymer-whey liposomes loaded with gingerol to heal intestinal wounds and neutralize oxidative stress

As a sustainable strategy to valorize the main effluent of the cheese industry and potent environmental pollutant, whey, several biopolymer-whey vesicles loaded with gingerol were tailored for counteracting intestinal oxidative stress and boosting wound healing. An eco-friendly method was used to combine whey with four different water-dispersible biopolymers (xanthan gum, tragacanth, Arabic gum and sodium alginate), phospholipid and a natural antioxidant (gingerol). The results of cryogenic transmission microscopy and dynamic light scattering indicated that the vesicles were mostly unilamellar and small in size (∼100 nm) with low polydispersity index, high negative zeta potential and ability to entrap a high amount of gingerol (up to 94%). The vesicles could maintain their structures in acidic and neutral media and Turbiscan® technology confirmed their stability during the storage. Vesicles prepared with whey and tragacanth exhibited the highest capability to protect intestinal cells from damages induced by hydrogen peroxide. When Arabic and tragacanth gums were added to the whey vesicles, the closure rate of the scratched area was fast and no trace of the wound was observed after 72 h of treatment. These promising findings could open a new horizon in the application of whey in nanomedicine for the treatment of intestinal damages.

Krill-Oil-Dependent Increases in HS-Omega-3 Index, Plasma Choline and Antioxidant Capacity in Well-Conditioned Power Training Athletes

There is evidence that both omega-3 polyunsaturated fatty acids (n-3 PUFAs) and choline can influence sports performance, but information establishing their combined effects when given in the form of krill oil during power training protocols is missing. The purpose of this study was therefore to characterize n-3 PUFA and choline profiles after a one-hour period of high-intensity physical workout after 12 weeks of supplementation. Thirty-five healthy power training athletes received either 2.5 g/day of Neptune krill oil^TM (550 mg EPA/DHA and 150 mg choline) or olive oil (placebo) in a randomized double-blind design. After 12 weeks, only the krill oil group showed a significant HS-Omega-3 Index increase from 4.82 to 6.77% and a reduction in the ARA/EPA ratio (from 50.72 to 13.61%) (p < 0.001). The krill oil group showed significantly higher recovery of choline concentrations relative to the placebo group from the end of the first to the beginning of the second exercise test (p = 0.04) and an 8% decrease in total antioxidant capacity post-exercise versus 21% in the placebo group (p = 0.35). In conclusion, krill oil can be used as a nutritional strategy for increasing the HS-Omega-3 Index, recover choline concentrations and address oxidative stress after intense power trainings.

Ethanol Extraction of Polar Lipids from Nannochloropsis oceanica for Food, Feed, and Biotechnology Applications Evaluated Using Lipidomic Approaches

Nannochloropsis oceanica can accumulate lipids and is a good source of polar lipids, which are emerging as new value-added compounds with high commercial value for the food, nutraceutical, and pharmaceutical industries. Some applications may limit the extraction solvents, such as food applications that require safe food-grade solvents, such as ethanol. However, the effect of using ethanol as an extraction solvent on the quality of the extracted polar lipidome, compared to other more traditional methods, is not yet well established. In this study, the polar lipid profile of N. oceanica extracts was obtained using different solvents, including chloroform/methanol (CM), dichloromethane/methanol (DM), dichloromethane/ethanol (DE), and ethanol (E), and evaluated by modern lipidomic methods using LC-MS/MS. Ultrasonic bath (E + USB)- and ultrasonic probe (E + USP)-assisted methodologies were implemented to increase the lipid extraction yields using ethanol. The polar lipid signature and antioxidant activity of DM, E + USB, and E + USP resemble conventional CM, demonstrating a similar extraction efficiency, while the DE and ethanol extracts were significantly different. Our results showed the impact of different extraction solvents in the polar lipid composition of the final extracts and demonstrated the feasibility of E + USB and E + USP as safe and food-grade sources of polar lipids, with the potential for high-added-value biotechnological applications.

Non-polar lipid from greenshell mussel (Perna canaliculus) inhibits osteoclast differentiation

The osteoclast-dependent bone resorption process is a crucial part of the bone regulatory system. The excessive function of osteoclasts can cause diseases of bone, joint, and other tissues such as osteoporosis and osteoarthritis. Greenshell mussel oil (GSM), a good source of long chain omega-3 polyunsaturated fatty acids (LCn-3PUFAs), was fractionated into total lipid, polar lipid, and non-polar lipid components and their anti-osteoclastogenic activity tested in RAW 264.7 cell cultures. Osteoclast differentiation process was achieved after 5 days of incubation with RANKL in 24-well culture plates. Introducing the non-polar lipid fraction into the culture caused a lack of cell differentiation, and a reduction in tartrate-resistant acid phosphatase (TRAP) activity and TRAP cell numbers in a dose-dependent manner (50% reduction at the concentration of 20 μg/mL, p < 0.001). Moreover, actin ring formation was significantly diminished by non-polar lipids at 10-20 μg/mL. The bone digestive enzymes released by osteoclasts into the pit formation were also compromised by downregulating gene expression of cathepsin K, carbonic anhydrase II (CA II), matrix metalloproteinase 9 (MMP-9), and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1). This study revealed that the non-polar lipid fraction of GSM oil contains bioactive substances which possess potent anti-osteoclastogenic activity.

Lipid-Based Nanocarrier System for the Effective Delivery of Nutraceuticals

Nutraceuticals possess several health benefits and functions; however, most nutraceuticals are prone to degradation in the gastrointestinal environment and have poor bioavailability. Application of a novel carrier system is of increasing importance to overcome obstacles and provide efficient applicability. Lipid-based nanocarriers provide a large surface-to-mass ratio, enhanced intestinal absorption by solubilization in the intestinal milieu, intestinal lymphatic transport, and altering enterocyte-based transport. A critical overview of the current limitation, preparation, and application of lipid-based nanocarriers (liposomes and niosomes) and lipid nanoparticles (SLNs and NLCs) is discussed. Physical and gastrointestinal stability and bioavailability of nanoencapsulated nutraceuticals are considered as well.

Polar Lipids Composition, Antioxidant and Anti-Inflammatory Activities of the Atlantic Red Seaweed Grateloupia turuturu

Grateloupia turuturu Yamada, 1941, is a red seaweed widely used for food in Japan and Korea which was recorded on the Atlantic Coast of Europe about twenty years ago. This seaweed presents eicosapentaenoic acid (EPA) and other polyunsaturated fatty acids (PUFAs) in its lipid fraction, a feature that sparked the interest on its potential applications. In seaweeds, PUFAs are mostly esterified to polar lipids, emerging as healthy phytochemicals. However, to date, these biomolecules are still unknown for G. turuturu. The present work aimed to identify the polar lipid profile of G. turuturu, using modern lipidomics approaches based on high performance liquid chromatography coupled to high resolution mass spectrometry (LC-MS) and gas chromatography coupled to mass spectrometry (GC-MS). The health benefits of polar lipids were identified by health lipid indices and the assessment of antioxidant and anti-inflammatory activities. The polar lipids profile identified from G. turuturu included 205 lipid species distributed over glycolipids, phospholipids, betaine lipids and phosphosphingolipids, which featured a high number of lipid species with EPA and PUFAs. The nutritional value of G. turuturu has been shown by its protein content, fatty acyl composition and health lipid indices, thus confirming G. turuturu as an alternative source of protein and lipids. Some of the lipid species assigned were associated to biological activity, as polar lipid extracts showed antioxidant activity evidenced by free radical scavenging potential for the 2,2'-azino-bis-3-ethyl benzothiazoline-6-sulfonic acid (ABTS^●+) radical (IC₅₀ ca. 130.4 μg mL^-1) and for the 2,2-diphenyl-1-picrylhydrazyl (DPPH^●) radical (IC₂₅ ca. 129.1 μg mL^-1) and anti-inflammatory activity by inhibition of the COX-2 enzyme (IC₅₀ ca. 33 µg mL^-1). Both antioxidant and anti-inflammatory activities were detected using a low concentration of extracts. This integrative approach contributes to increase the knowledge of G. turuturu as a species capable of providing nutrients and bioactive molecules with potential applications in the nutraceutical, pharmaceutical and cosmeceutical industries.

Characterization and bioactivities of phospholipids from squid viscera and gonads using ultra-performance liquid chromatography-Q-exactive orbitrap/mass spectrometry-based lipidomics and zebrafish models

There has been great interest in phospholipids (PLs) from marine by-products due to their long-chain polyunsaturated fatty acids with unique health and functional properties. Here, marine PLs from squid viscera and gonads were comprehensively characterized and compared by UPLC-Q-Exactive Orbitrap/MS-based lipidomics analysis. A total of thirteen phospholipid classes including 1223 molecular species were identified and quantified in both resources. PC, PE and SM were further isolated from the total PLs of squid viscera and gonads, respectively. All isolated squid PL components were first evaluated for anti-inflammatory, antioxidant and cardiovascular effects using in vivo zebrafish models. Our results showed the diversity, content and physiological functions of PLs from squid by-products, which provided a basis for their future application in the nutritional and pharmaceutical industry.

The Role of the Effects of Autophagy on NLRP3 Inflammasome in Inflammatory Nervous System Diseases

Autophagy is a stable self-sustaining process in eukaryotic cells. In this process, pathogens, abnormal proteins, and organelles are encapsulated by a bilayer membrane to form autophagosomes, which are then transferred to lysosomes for degradation. Autophagy is involved in many physiological and pathological processes. Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome, containing NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC) and pro-caspase-1, can activate caspase-1 to induce pyroptosis and lead to the maturation and secretion of interleukin-1 β (IL-1 β) and IL-18. NLRP3 inflammasome is related to many diseases. In recent years, autophagy has been reported to play a vital role by regulating the NLRP3 inflammasome in inflammatory nervous system diseases. However, the related mechanisms are not completely clarified. In this review, we sum up recent research about the role of the effects of autophagy on NLRP3 inflammasome in Alzheimer’s disease, chronic cerebral hypoperfusion, Parkinson’s disease, depression, cerebral ischemia/reperfusion injury, early brain injury after subarachnoid hemorrhage, and experimental autoimmune encephalomyelitis and analyzed the related mechanism to provide theoretical reference for the future research of inflammatory neurological diseases.

Impact of Rapeseed and Soy Lecithin on Postprandial Lipid Metabolism, Bile Acid Profile, and Gut Bacteria in Mice

SCOPE

Synthetic emulsifiers have recently been shown to promote metabolic syndrome and considerably alter gut microbiota. Yet, data are lacking regarding the effects of natural emulsifiers, such as plant lecithins rich in essential α-linolenic acid (ALA), on gut and metabolic health.

METHODS AND RESULTS

For 5 days, male Swiss mice are fed diets containing similar amounts of ALA and 0, 1, 3, or 10% rapeseed lecithin (RL) or 10% soy lecithin (SL). Following an overnight fast, they are force-fed the same oil mixture and euthanized after 90 minutes. The consumption of lecithin significantly increased fecal levels of the Clostridium leptum group (p = 0.0004), regardless of origin or dose, without altering hepatic or intestinal expression of genes of lipid metabolism. 10%-RL increased ALA abundance in plasma triacylglycerols at 90 minutes, reduced cecal bile acid hydrophobicity, and increased their sulfatation, as demonstrated by the increased hepatic RNA expression of Sult2a1 (p = 0.037) and cecal cholic acid-7 sulfate (CA-7S) concentration (p = 0.05) versus 0%-lecithin.

CONCLUSION

After only 5 days, nutritional doses of RL and SL modified gut bacteria in mice, by specifically increasing C. leptum group. RL also increased postprandial ALA abundance and induced beneficial modifications of the bile acid profile. ALA-rich lecithins, especially RL, may then appear as promising natural emulsifiers.

Effect of Drying on Nutritional Composition of Atlantic Sea Cucumber (Cucumaria frondosa) Viscera Derived from Newfoundland Fisheries

Cucumaria frondosa is the main sea cucumber species harvested from Newfoundland waters. During processing, the viscera of sea cucumber are usually discarded as waste. As a matter of fact, sea cucumber viscera are abundant in various nutrients and promising for valorization. In the present study, sea cucumber viscera were pretreated by air drying and freeze drying, and the nutritional compositions of the dried products were investigated, including proximate composition, lipid class, fatty acid profile, and amino acid composition. The dried viscera had similar levels of ash, lipids, and proteins compared to fresh viscera. Both air- and freeze-dried viscera had total fatty acid composition similar to fresh viscera, with high levels of omega-3 polyunsaturated fatty acids (PUFAs) (30–31%), especially eicosapentaenoic acid (27–28%), and low levels of omega-6 PUFAs (~1%). The dried samples were abundant in essential amino acids (46–51%). Compared to air-dried viscera, freeze-dried viscera contained a lower content of moisture and free fatty acids, and higher content of glycine and omega-3 PUFAs in phospholipid fraction. The high content of nutritious components in dried viscera of Cucumaria frondosa indicates their great potential for valorization into high-value products.

Krill oil and low-dose aspirin combination mitigates experimentally induced silicosis in rats: role of NF-κB/TGF-β1/MMP-9 pathway

This study is an attempt to assess pulmonary protective and antifibrotic potentials of a combination of aspirin, a widely used anti-inflammatory and cardioprotective agent, and krill oil, a naturally occurring omega-3 fatty acid source, against silica-induced pulmonary injury. For silicosis induction, silica particles (50 mg/rat, 0.1 mL 0.9% NaCl) were instilled intranasally into rats. Aspirin (10 mg/kg/day), krill oil (40 mg/kg/day), or their combination was administered orally for 56 days following silica exposure. Results showed that oral aspirin and krill oil combination significantly mitigated silica-induced pulmonary injury. Bronchoalveolar lavage fluid examination showed a decreased lactate dehydrogenase activity, total protein content, and accumulation of total and differential inflammatory cells. Oral aspirin and krill oil combination significantly attenuated silica-induced oxidative stress through the restoration of reduced glutathione concentration and catalase activity in addition to alleviation of elevated malondialdehyde and total nitric oxide contents. Moreover, aspirin and krill oil combination revealed considerable mitigation of silica-induced upregulated expression of the inflammatory and fibrotic mediators: nuclear factor kappa-B, transforming growth factor-β1, and matrix metalloproteinase-9. The antifibrotic effect was also evidenced through the decreased hydroxyproline content and the obvious restoration of lung architecture, as demonstrated upon histopathological examination. In conclusion, oral aspirin and krill oil combination can confer pulmonary protective, anti-inflammatory, and antifibrotic potentials against silica-induced pulmonary injury. This impact could be credited to the ability of this combination to activate resolution mechanisms, which, in turn, suppress the expression of inflammatory and fibrotic biomarkers and replenish antioxidant stores.

Polar lipidomic profile shows Chlorococcum amblystomatis as a promising source of value-added lipids

There is a growing trend to explore microalgae as an alternative resource for the food, feed, pharmaceutical, cosmetic and fuel industry. Moreover, the polar lipidome of microalgae is interesting because of the reports of bioactive polar lipids which could foster new applications for microalgae. In this work, we identified for the first time the Chlorococcum amblystomatis lipidome using hydrophilic interaction liquid chromatography-high resolution electrospray ionization- tandem mass spectrometry (HILIC-HR-ESI-MS/MS). The Chlorococcum amblystomatis strain had a lipid content of 20.77% and the fatty acid profile, determined by gas chromatography-mass spectrometry, has shown that this microalga contains high amounts of omega-3 polyunsaturated fatty acids (PUFAs). The lipidome identified included 245 molecular ions and 350 lipid species comprising 15 different classes of glycolipids (6), phospholipids (7) and betaine lipids (2). Of these, 157 lipid species and the main lipid species of each class were esterified with omega-3 PUFAs. The lipid extract has shown antioxidant activity and anti-inflammatory potential. Lipid extracts also had low values of atherogenic (0.54) and thrombogenic index (0.27). In conclusion, the lipid extracts of Chlorococcum amblystomatis have been found to be a source of lipids rich in omega-3 PUFAs for of great value for the food, feed, cosmetic, nutraceutical and pharmaceutical industries.

The effects of cooking salmon sous-vide on its antithrombotic properties, lipid profile and sensory characteristics

Fish contains bioactive polar lipids (PL) and is mainly consumed cooked. The aim of this study was to evaluate the sensory characteristics of sous-vide cooked salmon and the in vitro cardio-protective properties of its PL. PL were extracted from brined and un-brined sous-vide preparations in 52 °C, 65 °C, and 80 °C, while their antithrombotic cardio-protective properties were assessed in human platelets and their fatty acid (FA) content was evaluated by LC-MS. Sensory tests were performed using napping followed by check-all-that apply (CATA). Mild temperatures (52 °C, 65 °C) did not affect the inhibitory effect of PL from brined and un-brined salmon, against human platelet aggregation induced by platelet-activating factor (PAF), thrombin, adenosine diphosphate (ADP) or collagen. In higher temperatures used for pasteurization (80 °C), a reduction of antithrombotic properties was observed in PL from both un-brined and brined salmon samples. This reduction was accompanied by a decrease of their n3 eicosapentaenoic acid (EPA) and overall polyunsaturated FA (PUFA) content, but only in the PL of the un-brined salmon preparations. Thus, changes in the fatty acid content of PL of all sous vide salmon preparations, and especially of specific PUFA, seem to be associated with the observed changes in their antithrombotic potency. Changes in the content of the n-3 docosapentaenoic acid (DPA), a precursor of EPA and docosahexaenoic acid (DHA), seem to be associated with differences observed in the antithrombotic potency of PL from different sous vide salmon preparations. Taste attributes were not affected by the conditions of sous-vide preparations, whereas slight textural differences were observed in samples treated at 65 °C and 80 °C. These outcomes, if combined with the observed low values of the n-6/n-3 PUFA ratio in PL of all sous-vide preparations, further suggest a beneficial role for such a mild cooking procedure for preserving the antithrombotic and cardio-protective properties of salmon without affecting its sensory characteristics.

Neurobiological effects of phospholipids in vitro: Relevance to stress-related disorders

Nutrition is a crucial component for maintenance of brain function and mental health. Accumulating evidence suggests that certain molecular compounds derived from diet can exert neuroprotective effects against chronic stress, and moreover improve important neuronal processes vulnerable to the stress response, such as plasticity and neurogenesis. Phospholipids are naturally occurring amphipathic molecules with promising potential to promote brain health. However, it is unclear whether phospholipids are able to modulate neuronal function directly under a stress-related context. In this study, we investigate the neuroprotective effects of phosphatidylcholine (PC), lysophosphatidylcholine (LPC), phosphatidylserine (PS), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylglycerol (PG), phosphatidic acid (PA), sphingomyelin (SM) and cardiolipin (CL) against corticosterone (CORT)-induced cytotoxicity in primary cultured rat cortical neurons. In addition, we examine their capacity to modulate proliferation and differentiation of hippocampal neural progenitor cells (NPCs).

We show that PS, PG and PE can reverse CORT-induced cytotoxicity and neuronal depletion in cortical cells. On the other hand, phospholipid exposure was unable to prevent the decrease of Bdnf expression produced by CORT. Interestingly, PS was able to increase hippocampal NPCs neurosphere size, and PE elicited a significant increase in astrocytic differentiation in hippocampal NPCs. Together, these results indicate that specific phospholipids protect cortical cells against CORT-induced cytotoxicity and improve proliferation and astrocytic differentiation in hippocampal NPCs, suggesting potential implications on neurodevelopmental and neuroprotective pathways relevant for stress-related disorders.

Recent Advances in Marine-Based Nutraceuticals and Their Health Benefits

The oceans have been the Earth's most valuable source of food. They have now also become a valuable and versatile source of bioactive compounds. The significance of marine organisms as a natural source of new substances that may contribute to the food sector and the overall health of humans are expanding. This review is an update on the recent studies of functional seafood compounds (chitin and chitosan, pigments from algae, fish lipids and omega-3 fatty acids, essential amino acids and bioactive proteins/peptides, polysaccharides, phenolic compounds, and minerals) focusing on their potential use as nutraceuticals and health benefits.

The involvement of NLRP3 inflammasome in the treatment of Alzheimer's disease

Alzheimer's disease (AD) is one of the most common neurodegenerative diseases, and it is characterised by progressive deterioration in cognitive and memory abilities, which can severely influence the elderly population's daily living abilities. Although researchers have made great efforts in the field of AD, there are still no well-established strategies to prevent and treat this disease. Therefore, better clarification of the molecular mechanisms associated with the onset and progression of AD is critical to provide a theoretical basis for the establishment of novel preventive and therapeutic strategies. Currently, it is generally believed that neuroinflammation plays a key role in the pathogenesis of AD. Inflammasome, a multiprotein complex, is involved in the innate immune system, and it can mediate inflammatory responses and pyroptosis, which lead to neurodegeneration. Among the various types of inflammasomes, the NLRP3 inflammasome is the most characterised in neurodegenerative diseases, especially in AD. The activation of the NLRP3 inflammasome causes the generation of caspase-1-mediated interleukin (IL)-1β and IL-18 in microglia cells, where neuroinflammation is involved in the development and progression of AD. Thus, the NLRP3 inflammasome is likely to be a crucial therapeutic molecular target for AD via regulating neuroinflammation. In this review, we summarise the current knowledge on the role and regulatory mechanisms of the NLRP3 inflammasome in the pathogenic mechanisms of AD. We also focus on a series of potential therapeutic treatments targeting NLRP3 inflammasome for AD. Further clarification of the regulatory mechanisms of the NLRP3 inflammasome in AD may provide more useful clues to develop novel AD treatment strategies.

Omega 3 Fatty Acids and COVID-19: A Comprehensive Review

The rapid international spread of severe acute respiratory syndrome coronavirus 2 responsible for coronavirus disease 2019 (COVID-19) has posed a global health emergency in 2020. It has affected over 52 million people and led to over 1.29 million deaths worldwide, as of November 13th, 2020. Patients diagnosed with COVID-19 present with symptoms ranging from none to severe and include fever, shortness of breath, dry cough, anosmia, and gastrointestinal abnormalities. Severe complications are largely due to overdrive of the host immune system leading to "cytokine storm". This results in disseminated intravascular coagulation, acute respiratory distress syndrome, multiple organ dysfunction syndrome, and death. Due to its highly infectious nature and concerning mortality rate, every effort has been focused on prevention and creating new medications or repurposing old treatment options to ameliorate the suffering of COVID-19 patients including the immune dysregulation. Omega-3 fatty acids are known to be incorporated throughout the body into the bi-phospholipid layer of the cell membrane leading to the production of less pro-inflammatory mediators compared to other fatty acids that are more prevalent in the Western diet. In this article, the benefits of omega-3 fatty acids, especially eicosapentaenoic acid and docosahexaenoic acid, including their anti-inflammatory, immunomodulating, and possible antiviral effects have been discussed.

Rapeseed Lecithin Increases Lymphatic Lipid Output and α-Linolenic Acid Bioavailability in Rats

BACKGROUND

Soybean lecithin, a plant-based emulsifier widely used in food, is capable of modulating postprandial lipid metabolism. With arising concerns of sustainability, alternative sources of vegetal lecithin are urgently needed, and their metabolic effects must be characterized.

OBJECTIVES

We evaluated the impact of increasing doses of rapeseed lecithin (RL), rich in essential α-linolenic acid (ALA), on postprandial lipid metabolism and ALA bioavailability in lymph-cannulated rats.

METHODS

Male Wistar rats (8 weeks old) undergoing a mesenteric lymph duct cannulation were intragastrically administered 1 g of an oil mixture containing 4% ALA and 0, 1, 3, 10, or 30% RL (5 groups). Lymph fractions were collected for 6 h. Lymph lipids and chylomicrons (CMs) were characterized. The expression of genes implicated in intestinal lipid metabolism was determined in the duodenum at 6 h. Data was analyzed using either sigmoidal or linear mixed-effects models, or one-way ANOVA, where appropriate.

RESULTS

RL dose-dependently increased the lymphatic recovery (AUC) of total lipids (1100 μg/mL·h per additional RL%; P = 0.010) and ALA (50 μg/mL·h per additional RL%; P = 0.0076). RL induced a faster appearance of ALA in lymph, as evidenced by the exponential decrease of the rate of appearance of ALA with RL (R2 = 0.26; P = 0.0064). Although the number of CMs was unaffected by RL, CM diameter was increased in the 30%-RL group, compared to the control group (0% RL), by 86% at 3-4 h (P = 0.065) and by 81% at 4-6 h (P = 0.0002) following administration. This increase was positively correlated with the duodenal mRNA expression of microsomal triglyceride transfer protein (Mttp; ρ= 0.63; P = 0.0052). The expression of Mttp and secretion-associated, ras-related GTPase 1 gene homolog B (Sar1b, CM secretion), carnitine palmitoyltransferase IA (Cpt1a) and acyl-coenzyme A oxidase 1 (Acox1, beta-oxidation), and fatty acid desaturase 2 (Fads2, bioconversion of ALA into long-chain n-3 PUFAs) were, respectively, 49%, 29%, 74%, 48%, and 55% higher in the 30%-RL group vs. the control group (P < 0.05).

CONCLUSIONS

In rats, RL enhanced lymphatic lipid output, as well as the rate of appearance of ALA, which may promote its subsequent bioavailability and metabolic fate.

Lecithins from Vegetable, Land, and Marine Animal Sources and Their Potential Applications for Cosmetic, Food, and Pharmaceutical Sectors

The aim of this work was to review the reported information about the phospholipid composition of lecithins derived from several natural sources (lipids of plant, animal, and marine origin) and describe their main applications for the cosmetic, food, and pharmaceutical sectors. This study was carried out using specialized search engines and according to the following inclusion criteria: (i) documents published between 2005 and 2020, (ii) sources of lecithins, (iii) phospholipidic composition of lecithins, and (iv) uses and applications of lecithins. Nevertheless, this work is presented as a narrative review. Results of the review indicated that the most studied source of lecithin is soybean, followed by sunflower and egg yolk. Contrarily, only a few numbers of reports focused on lecithins derived from marine animals despite the relevance of this source in association with an even higher composition of phospholipids than in case of those derived from plant sources. Finally, the main applications of lecithins were found to be related to their nutritional aspects and ability as emulsion stabilizers and lipid component of liposomes.