And Α-linolenic Acid Research Articles

Targeted LC-MS/MS method of oxylipin profiling reveals differentially expressed serum metabolites in type 2 diabetes mice with panaxynol

Panaxynol is a bioactive polyacetylene in food plants; however, its specific benefits in diabetes and metabolic disorders remain unclear. Previous studies have mainly focused on biochemical indicators and clinical evaluations. Limited research has systematically elucidated the beneficial effects of panaxynol from the oxylipins perspective. In this study, we employed an oxylipin analysis platform we previously established using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) based on the multiple reaction monitoring (MRM) method for the profiling of oxylipins. After a 7-week administration of panaxynol to db/db mice, significant alterations in serum oxylipins and potential benefits to hyperglycemia, insulin resistance, and hepatic steatosis were observed. Our analysis also revealed correlations among epoxygenase products derived from arachidonic acid (AA), linoleic acid (LA), and α-linolenic acid (ALA) via cytochrome P450 (CYP) pathways. Furthermore, six potential oxylipins were identified, as offering insights into the mechanisms by which panaxynol may modulate diabetes. These results provide the first in vivo evidence of the impact of panaxynol on oxylipin metabolism and lay the foundation for developing panaxynol as a nutraceutical for diabetes management.

Mass spectrometry unveils heat-induced changes in yolk oxylipins and key lipid molecules during home cooking

IntroductionOxylipins, as a widespread class of metabolic markers following oxidative stress, and several studies have reported dietary regulation of lipid metabolism. However, there is a lack of investigation of dietary oxylipins, especially cooking-induced changes in food lipid oxidation. ObjectivesInvestigated the effects of cooking methods and lipid profiles on polyunsaturated fatty acids derived oxylipins generation within egg yolks. MethodsThe lipid profile of egg yolk was determined by UPLC-QTOF-MS/MS, oxylipins were detected by HPLC-QTRAP-MS/MS, while the total fatty acid content was quantified by GC-FID. Random Forest (RF) and Partial Least Squares (PLS) regression models were employed to explore the association between oxidized lipids and key lipid species. ResultsHeating reduced egg yolk docosahexaenoic acid (DHA) content, and no consistent trends for arachidonic acid (AA), linoleic acid (LA), and linolenic acid (ALA). Yolk lipid composition affected triacylglycerol (TG), phosphatidylethanolamine (PE), and LA-monoepoxide contents after cooking. 9- and 13-HODE (hydroxyoctadecadienoic acid), 9,10,13-TriHOME (trihydroxyoctadecenoic acid), 9,10- and 12,13-EpOME (epoxyoctadecenoic acid), 9,10- and 12,13-DiHOME (dihydroxyoctadecenoic acid), 5-HETE (hydroxyeicosatetraenoic acid), and 4-HDHA (hydroxydocosahexaenoic acid) were the prevalent oxylipins with high concentrations, accounting for 1.08 %–29.58 % of the total content of 29 oxylipins. Steaming resulted in a 1.9-fold increase in oxylipin concentrations in yolks compared to raw yolks, and boiling with or without shells (poaching) resulted in a 1.30- to 1.76-fold increase in oxylipin concentrations. In contrast, pan-fried yolks exhibited the lowest and least variable levels of total oxylipins, while still retaining some epoxides, including epoxyeicosatrienoic acid (EET) and EpOME. Utilizing big data analysis, we mapped the oxylipin network in both ordinary and DHA-enriched egg yolks, revealing a strong correlation between cooking-induced oxylipin production and variations in 24 lipid species. ConclusionRevealed the potential mechanisms and key lipid molecules for heating-induced oxylipin production of yolk through lipidomics and big data analysis.

Effects of a food supplement containing phosphatidylserine on cognitive function in Chinese older adults with mild cognitive impairment: A randomized double-blind, placebo-controlled trial

BackgroundPhosphatidylserine (PS) and α-Linolenic acid (ALA), are positively associated with cognitive function, but their combination effects and possible mechanisms remain unclear. We aimed to explore the effects on cognition and potential mechanism of the supplements. MethodsThis randomized, double-blind, placebo-controlled trial recruited 190 MCI patients in Tianjin, China, and randomly assigned in intervention group and placebo group. Each group consumed two capsules every day for 12 months. Each capsule for intervention group contains 144 mg ALA, 31.5 mg PS and 3.6 mg Ginkgo total flavonoids as main functional components, with 0.48 mg Vitamin B1 (as thiamine hydrochloride), 0.48 mg Vitamin B6 (as pyridoxine hydrochloride) and 90 μg folic acid as supplement. Capsules for placebo group were identical but contain no active ingredients. Cognitive function, serum n-3 polyunsaturated fatty acids (PUFAs) and neurotransmitters were assessed at baseline and 12 months. Linear mixed effects model and causal mediation analysis were conducted to explore the effects and potential mechanism of the intervention. ResultsA total of 190 participants (mean [SD] age, 67.95 [5.62] years; 70 (36.8 %) male and 120 (63.2 %) female) were randomized to the placebo group (n = 95) and intervention group (n = 95). Compared with placebo group, the intervention group had statistically significant improvements in arithmetic testing (β, 0.688; 95 % CI, 0.103–1.274), the similarity test (β, 1.070; 95 % CI, 0.472–1.667) and short-term memory (β, 0.600; 95 % CI, 0.399–0.800). Besides, the intervention group had statistically significant increases in serum ALA (β, 1.620; 95 % CI, 0.967–2.265), DHA (β, 2.797; 95 % CI, 1.075–4.532), EPA (β, 1.472; 95 % CI, 0.296–2.643), acetylcholine (β, 0.441; 95 % CI, 0.415–0.468), GABA (β, 0.009; 95 % CI, 0.001–0.016) and 5-HT (β, 0.160; 95 % CI, 0.081–0.238) compared to the placebo group. And the intervention may improve short-term memory by increasing serum ALA levels (average causal mediation effect = 0.132, 95 % CI, 0.053–0.225) with 19.7 % mediation proportion. ConclusionsThis food supplement containing phosphatidylserine could improve different cognitive functions of MCI patients, especially short-term memory, and increase serum n-3 PUFAs and neurotransmitters levels. Serum ALA level might play a mediation role.

Oil polyunsaturated fatty acid composition but not tocopherol levels determine oxylipin formation in plant and algae oils during pan-frying

The oxidation of linoleic acid (LA) and α-linolenic acid (ALA) in plant oils results in primary oxidation products known as oxylipins. It is not known whether the mechanisms of oxidation are driven primarily by oil polyunsaturated fatty acid (PUFA) composition (i.e., more double bonds resulting in more rapid oxidation) or antioxidant (tocopherol) content. The present study addressed this unknown by measuring the effects of pan-frying on LA- and ALA-derived oxylipin concentrations in plant and algae oils with different baseline fatty acid and tocopherol concentrations. Oxylipins, free fatty acids and tocopherols were quantified in algae, olive, corn, canola, and soybean oils before and after 30 minutes of pan-frying. Fatty acid epoxides and hydroxides of LA or ALA were significantly elevated after pan-frying, whereas fatty acid diols were reduced. The level of change in oxylipins was lower in low-PUFA algae and extra virgin olive oils compared to soybean, canola and corn oils (high in PUFAs). Tocopherols decreased significantly after 30 minutes of pan-frying, particularly in oils with low PUFA composition. Minor changes were observed in free fatty acids. Our findings demonstrate that oil PUFA composition is a greater determinant of lipid oxidation than tocopherol content, and that PUFAs in high LA or ALA oils may spare tocopherol oxidation by acting as free radical scavengers.

Microemulsification of peony (Paeonia suffruticosa Andr.) seed oil and its fatty acids: A comparative study in antioxidant and storage stability

The effectiveness of oil-in-water (O/W) microemulsion (ME) in enhancing the oxidation and the storage stability of peony seed oil (PSO), its fatty acid mixtures (FAM-1, FAM-2), and α-linolenic acid (ALA) were investigated in this work. Storage stability was assessed by measuring iodine value, acid value, and fatty acid composition under varying temperature conditions devoid of oxygen. Additionally, antioxidant stability of both the oil phase and ME was evaluated by measuring the peroxide value, with oxidation kinetics modeled using the Arrhenius equation to predict shelf life. The results demonstrated that the change of iodine values for PSO, FAM-1, FAM-2 and ALA at 4, and -20 °C for 90 days was not obvious. At 25℃, the ALA content in PSO, FAM-1, FAM-2 and ALA samples decreased by 4.81%, 3.94%, 2.86%, and 0.12% after 90 days. Therefore, low temperature without oxygen environment is more suitable for the storage of oil and fatty acid. Embedding PSO in ME can effectively control the generation rate of peroxides. At 4°C, the shelf life of PSO, FAM-1 and FAM-2 encapsulated in MEs was prolonged by 28.36%, 9.89% and 4.24%, respectively. Thes results confirm that O/W ME can improve the oxidation stability and prolong the storage period of fat-soluble compounds. These findings provide valuable insights into enhancing the oxidative stability of PSO and its fatty acids, thereby facilitating the development of ME products loaded with fatty acids in the future.

The role of C18 fatty acids in improving the digestion and retrogradation properties of highland barley starch

In this study, five C18 fatty acids (FA) with different numbers of double bonds and configurations including stearic acid (SA), oleic acid (OA), elaidic acid (EA), linoleic acid (LA), and α-linolenic acid (ALA), were selected to prepare highland barely starch (HBS)-FA complexes to modulate digestibility and elaborate the underlying mechanism. The results showed that HBS-SA had the highest complex index (34.18 %), relative crystallinity (17.62 %) and single helix content (25.78 %). Furthermore, the HBS-C18 FA complexes were formed by EA (C18 FA with monounsaturated bonds) that had the highest R1047/1022 (1.0509) and lowest full width at half-maximum (FWHM, 20.85), suggesting good short-range ordered structure. Moreover, all C18 FAs could form two kinds of V-type complexes with HBS, which can be confirmed by the results of CLSM and DSC measurements, and all of them showed significantly lower digestibility. HBS-EA possessed the highest resistant starch content (20.17 %), while HBS-SA had the highest slowly digestible starch content (26.61 %). In addition, the inhibition of HBS retrogradation by fatty acid addition was further proven, where HBS-SA gel firmness (37.80 g) and aging enthalpy value were the lowest, indicating the most effective. Overall, compounding with fatty acids, especially SA, could be used as a novel way to make functional foods based on HBS.

Lipidomics analysis unveils the dynamic alterations of lipid degradation in rice bran during storage

Recent explorations into rice bran oil (RBO) have highlighted its potential, owing to an advantageous fatty acid profile in the context of health and nutrition. Despite this, the susceptibility of rice bran lipids to oxidative degradation during storage remains a critical concern. This study focuses on the evolution of lipid degradation in RBO during storage, examining the increase in free fatty acids (FFAs), the formation of oxylipids, and the generation of volatile secondary oxidation products. Our findings reveal a substantial rise in FFA levels, from 109.55 to 354.06 mg/g, after 14 days of storage, highlighting significant lipid deterioration. Notably, key oxylipids, including 9,10-EpOME, 12,13(9,10)-DiHOME, and 13-oxoODE, were identified, with a demonstrated positive correlation between total oxylipids and free polyunsaturated fatty acids (PUFAs), specifically linoleic acid (LA) and α-linolenic acid (ALA). Furthermore, the study provides a detailed analysis of primary volatile secondary oxidation products. The insights gained from this study not only sheds light on the underlying mechanisms of lipid rancidity in rice bran but also offers significant implications for extending the shelf life and preserving the nutritional quality of RBO, aligning with the increasing global interest in this high-quality oil.

Exploration of markers in oxidized rancidity walnut kernels based on lipidomics and volatolomics

Walnut kernels are prone to oxidation and rancidity due to their rich lipid composition, but the existing evaluation indicators are not sensitive enough to promote their industrial development. This study aims to investigate the potential markers in oxidative rancidity walnut kernels using lipidomics and volatolomics. The results showed that the antioxidant capacity of walnut kernels significantly decreased after oxidation, with the decreasing of total phenolic content from 36276.34 mg GAE/kg to 31281.53 mg GAE/kg, the DPPH and ABTS free radical scavenging activity from 89.25% to 73.54%, and 61.69% to 43.73%, respectively. The activities of lipoxygenase (LOX) and lipase (LPS) increased by 6.08-fold and 0.33-fold, respectively. By combining volatolomics and chemometrics methods, it was found that significant differences existed in the content of hexanal, caproic acid, 1-pentanol, (E)-2-octenal, and 2-heptanenal before and after walnut kernel oxidation (VIP > 1). Based on the results of lipidomics, it can be concluded that the above five compounds can serve as characteristic markers for walnut kernel oxidative rancidity, mainly produced through glycerol phospholipid (GPL), glyceride, linoleic acid (LA), and α-linolenic acid (ALA) metabolism pathways. Possible mechanisms of lipid degradation in oxidized walnut kernels were also proposed, providing technical support for the storage, preservation, and high-value utilization of walnut kernels.

Investigating the effect of wall material and pressure homogenisation on encapsulation parameters and thermal stability in chia seed oil microcapsules

Aim To evaluate the effect of different wall material (WM) matrices followed by homogenisation to encapsulate chia seed oil (CSO) using freeze drying technology. Methods CSO was encapsulated using three ratios (100/0, 50/50, and 100/0) of two WM matrices: MTS/WPC (modified tapioca starch–whey protein concentrate) and MD/WPC (maltodextrin–whey protein concentrate). The evaluation included encapsulation efficiency (EE), oxidative stability, and α-linolenic acid (ALA) retention. Homogenised microcapsules (-H) were then assessed for storage and thermal stability, along with cumulative oil release. Results The MD-WPC-H 50/50 microcapsules had superior EE (97.32%), higher ALA retention (60.2%), storage stability (up to 30 days), higher thermal stability (up to 700 °C), and desirable oil release in simulated condition. Conclusion Selecting suitable WM and homogenisation is key for improving EE, storage, thermal stability, and targeted release. The CSO microcapsule can serve as a functional ingredient to improve the quality of diverse food products.

Effects of Replacing Fishmeal with Algal Biomass (Pavlova sp. 459) on Membrane Lipid Composition of Atlantic Salmon (Salmo salar) Parr Muscle and Liver Tissues

A 12-week feeding trial examined the dietary impact of replacing fishmeal (FM) with algal biomass (AB) derived from Pavlova sp. strain CCMP459 (Pav459) in Atlantic salmon diets. Three distinct diets were formulated: a control diet featuring 20% FM and 7% fish oil (FO), an experimental diet incorporating a 50:50 blend of FM and AB Pav459 and reduced FO (10% FM; 4.5% FO; 10% AB), and a second experimental diet with full replacement of FM with AB Pav459 and further reduction in FO (1.75% FO; 20% AB). Replacing FM with AB Pav459 showed no significant effects on the growth performance of Atlantic salmon. Fish across all diets exhibited growth exceeding 200% from their initial weight. Analysis of total lipid content after the 12-week trial revealed no significant differences among the diets. However, individual proportions of omega-3 (ω3) and omega-6 (ω6) fatty acids varied. Fatty acid profiling in muscle and liver tissues showed distinct compositions reflective of dietary treatments. Linoleic acid (LA) and α-linolenic acid (ALA) exhibited higher proportions in total fatty acids than in membrane lipids. Docosahexaenoic acid (DHA) emerged as the predominant fatty acid in the membranes of both liver and muscle tissues. Furthermore, an analysis of sterol composition in Pavlova and salmon muscle tissue showed the presence of important sterols, including conventionally animal-associated cholesterol. This emphasizes the suitability of microorganisms, such as Pav459, for synthesizing diverse nutrients. Stable isotope analysis demonstrated direct incorporation of eicosapentaenoic acid (EPA) and DHA from diets into salmon tissues. Notably, minimal biosynthesis from the precursor ALA was observed, reaffirming the utility of Pav459-derived fatty acids. The EPA+DHA proportions in the fillet consistently met daily human consumption requirements across all dietary conditions, supporting the use of Pav459 algal biomass as an alternative to FM.

Summer fades, deer change: Photoperiodic control of cellular seasonal acclimatization of skeletal muscle

We found major seasonal changes of polyunsaturated fatty acids (PUFAs) in muscular phospholipids (PL) in a large non-hibernating mammal, the red deer (Cervus elaphus). Dietary supply of essential linoleic acid (LA) and α-linolenic acid (ALA) had no, or only weak influence, respectively. We further found correlations of PL PUFA concentrations with the activity of key metabolic enzymes, independent of higher winter expression. Activity of the sarcoplasmic reticulum (SR) Ca++-ATPase increased with SR PL concentrations of n-6 PUFA, and of cytochrome c oxidase and citrate synthase, indicators of ATP-production, with concentrations of eicosapentaenoic acid in mitochondrial PL. All detected cyclic molecular changes were controlled by photoperiod and are likely of general relevance for mammals living in seasonal environments, including humans. During winter, these changes at the molecular level presumably compensate for Arrhenius effects in the colder peripheral body parts and thus enable a thrifty life at lower body temperature.

Climate-based variability in the essential fatty acid composition of soybean oil

BackgroundSoybean oil is a major dietary source of the essential fatty acids linoleic acid (LA) and α-linolenic acid (ALA); however, high-daytime temperatures during seed development reduce desaturase activity in soybeans. The resultant reduction in LA and ALA levels is a phenomenon well-known to soybean breeders, although the impact of this interaction between plants and environment on human nutrition is poorly understood. ObjectivesUsing data from the literature, we developed a model for soybean essential fatty acid composition. Combining this model with contemporary agricultural and meteorological data sets, we determined whether insufficiency of essential fatty acids could result from geographic, intrayear, or interyear variability. MethodsWe modeled this change using 233 data points from 16 studies that provided fatty acid composition data from plants grown under daytime high temperatures ranging from 15°C to 40°C. ResultsAs temperature increased, LA and ALA concentrations decreased from 55% to 30% and 13% to 3.5%, respectively. Application of the model to daytime high temperatures from 2 growth periods over 6 y showed significant regional, interyear, and intrayear variation in essential fatty acid content (P < 0.05). Using county yield data, we developed oil fatty acid models for the 3 top-producing regions of the United States. From this work, it was determined that soybean oil manufactured from soybeans in the southern United States may contain insufficient ALA to meet human nutritional needs because of high-daytime temperatures. ConclusionsThis work suggests that climate-based variation may result in many human populations not achieving an adequate daily intake of ALA.

Microbial production of docosahexaenoic acid (DHA): biosynthetic pathways, physical parameter optimization, and health benefits.

Omega-3 fatty acids, including docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and α-linolenic acid (ALA), are essential polyunsaturated fatty acids with diverse health benefits. The limited conversion of dietary DHA necessitates its consumption as food supplements. Omega-3 fatty acids possess anti-arrhythmic and anti-inflammatory capabilities, contributing to cardiovascular health. Additionally, DHA consumption is linked to improved vision, brain, and memory development. Furthermore, omega-3 fatty acids offer protection against various health conditions, such as celiac disease, Alzheimer's, hypertension, thrombosis, heart diseases, depression, diabetes, and certain cancers. Fish oil from pelagic cold-water fish remains the primary source of omega-3 fatty acids, but the global population burden creates a demand-supply gap. Thus, researchers have explored alternative sources, including microbial systems, for omega-3 production. Microbial sources, particularly oleaginous actinomycetes, microalgae like Nannochloropsis and among microbial systems, Thraustochytrids stand out as they can store up to 50% of their dry weight in lipids. The microbial production of omega-3 fatty acids is a potential solution to meet the global demand, as these microorganisms can utilize various carbon sources, including organic waste. The biosynthesis of omega-3 fatty acids involves both aerobic and anaerobic pathways, with bacterial polyketide and PKS-like PUFA synthase as essential enzymatic complexes. Optimization of physicochemical parameters, such as carbon and nitrogen sources, pH, temperature, and salinity, plays a crucial role in maximizing DHA production in microbial systems. Overall, microbial sources hold significant promise in meeting the global demand for omega-3 fatty acids, offering an efficient and sustainable solution for enhancing human health.

Oxylipin secretion by human CD3+ T lymphocytes in vitro is modified by the exogenous essential fatty acid ratio and life stage.

Immune function changes across the life stages; for example, senior adults exhibit a tendency towards a weaker cell-mediated immune response and a stronger inflammatory response than younger adults. This might be partly mediated by changes in oxylipin synthesis across the life course. Oxylipins are oxidation products of polyunsaturated fatty acids (PUFAs) that modulate immune function and inflammation. A number of PUFAs are precursors to oxylipins, including the essential fatty acids (EFAs) linoleic acid (LA) and α-linolenic acid (ALA). LA and ALA are also substrates for synthesis of longer chain PUFAs. Studies with stable isotopes have shown that the relative amounts of LA and ALA can influence their partitioning by T lymphocytes between conversion to longer chain PUFAs and to oxylipins. It is not known whether the relative availability of EFA substrates influences the overall pattern of oxylipin secretion by human T cells or if this changes across the life stages. To address this, the oxylipin profile was determined in supernatants from resting and mitogen activated human CD3+ T cell cultures incubated in medium containing an EFA ratio of either 5:1 or 8:1 (LA : ALA). Furthermore, oxylipin profiles in supernatants of T cells from three life stages, namely fetal (derived from umbilical cord blood), adults and seniors, treated with the 5:1 EFA ratio were determined. The extracellular oxylipin profiles were affected more by the EFA ratio than mitogen stimulation such that n-3 PUFA-derived oxylipin concentrations were higher with the 5:1 EFA ratio than the 8:1 ratio, possibly due to PUFA precursor competition for lipoxygenases. 47 oxylipin species were measured in all cell culture supernatants. Extracellular oxylipin concentrations were generally higher for fetal T cells than for T cells from adult and senior donors, although the composition of oxylipins was similar across the life stages. The contribution of oxylipins towards an immunological phenotype might be due to the capacity of T cells to synthesize oxylipins rather than the nature of the oxylipins produced.

Associations of specific dietary unsaturated fatty acids with risk of overweight/obesity: population-based cohort study.

The role of specific unsaturated fatty acids (FAs) in the development of overweight/obesity remains unclear in the general population. Here, we aimed to explore the associations of different types of unsaturated FAs with overweight/obesity risk among the Chinese population. Eight thousand seven hundred forty-two subjects free of overweight/obesity at entry in the China Health and Nutrition Survey (CHNS) were followed up until 2015. Dietary unsaturated FAs were assessed by 3-day 24-h recalls with a weighing method in each wave. Cox regression models were used to obtain the hazard ratios (HRs) and 95% confidence intervals (CIs) for overweight/obesity risk associated with unsaturated FAs. During a median follow-up of 7 years, 2,753 subjects (1,350 males and 1,403 females) developed overweight/obesity. Consuming more monounsaturated FAs (MUFAs) was associated with a lower risk of overweight/obesity (highest vs. lowest quartile: HR 0.80, 95% CI 0.67-0.96; P-trend = 0.010). Similar inverse associations were observed for plant-MUFAs (HRQ4vsQ1 0.83, 95% CI: 0.73-0.94; P-trend = 0.003) and animal-MUFAs (HRQ4vsQ1 0.77, 95% CI: 0.64-0.94; P-trend = 0.004), total dietary oleic acid (OA) (HRQ4vsQ1 0.66, 95% CI: 0.55-0.79; P-trend <0.001), plant-OA (HRQ4vsQ1 0.73, 95% CI: 0.64-0.83; P-trend <0.001) and animal-OA (HRQ4vsQ1 0.68, 95% CI: 0.55-0.84; P-trend <0.001). In addition, the intakes of n-3 polyunsaturated FAs (PUFAs) (HRQ4vsQ1 1.24, 95% CI: 1.09-1.42; P-trend = 0.017) and α-linolenic acid (ALA) (HRQ4vsQ1 1.22, 95% CI: 1.07-1.39; P-trend = 0.039) but not marine n-3 PUFAs were positively linked to overweight/obesity risk. Consumption of n-6 PUFAs (HRQ4vsQ1 1.13, 95% CI: 0.99-1.28; P-trend = 0.014) and linoleic acid (LA) (HRQ4vsQ1 1.11, 95% CI: 0.98-1.26; P-trend = 0.020) had marginal and positive relationships with the incidence of overweight/obesity. N-6/n-3 PUFA ratio ranging from 5.7 to 12.6 was related to higher risk of overweight/obesity. Higher dietary intake of MUFAs was associated with lower overweight/obesity risk, which was mainly driven by dietary OA from either plant or animal sources. Intakes of ALA, n-6 PUFAs and LA were related to higher risk of overweight/obesity. These results support consuming more MUFAs for maintaining a healthy body weight among the Chinese population.

Lipid flipping in the omega-3 fatty-acid transporter

Mfsd2a is the transporter for docosahexaenoic acid (DHA), an omega-3 fatty acid, across the blood brain barrier (BBB). Defects in Mfsd2a are linked to ailments from behavioral and motor dysfunctions to microcephaly. Mfsd2a transports long-chain unsaturated fatty-acids, including DHA and α-linolenic acid (ALA), that are attached to the zwitterionic lysophosphatidylcholine (LPC) headgroup. Even with the recently determined structures of Mfsd2a, the molecular details of how this transporter performs the energetically unfavorable task of translocating and flipping lysolipids across the lipid bilayer remains unclear. Here, we report five single-particle cryo-EM structures of Danio rerio Mfsd2a (drMfsd2a): in the inward-open conformation in the ligand-free state and displaying lipid-like densities modeled as ALA-LPC at four distinct positions. These Mfsd2a snapshots detail the flipping mechanism for lipid-LPC from outer to inner membrane leaflet and release for membrane integration on the cytoplasmic side. These results also map Mfsd2a mutants that disrupt lipid-LPC transport and are associated with disease.

The Impact of Linoleic Acid on Infant Health in the Absence or Presence of DHA in Infant Formulas

Both linoleic acid (LA) and α-linolenic acid (ALA) are essential dietary fatty acids, and a balanced dietary supply of these is of the utmost importance for health. In many countries across the globe, the LA level and LA/ALA ratio in breast milk (BM) are high. For infant formula (IF), the maximum LA level set by authorities (e.g., Codex or China) is 1400 mg LA/100 kcal ≈ 28% of total fatty acid (FA) ≈ 12.6% of energy. The aims of this study are: (1) to provide an overview of polyunsaturated fatty acid (PUFA) levels in BM across the world, and (2) to determine the health impact of different LA levels and LA/ALA ratios in IF by reviewing the published literature in the context of the current regulatory framework. The lipid composition of BM from mothers living in 31 different countries was determined based on a literature review. This review also includes data from infant studies (intervention/cohort) on nutritional needs regarding LA and ALA, safety, and biological effects. The impact of various LA/ALA ratios in IF on DHA status was assessed within the context of the current worldwide regulatory framework including China and the EU. Country averages of LA and ALA in BM range from 8.5–26.9% FA and 0.3–2.65% FA, respectively. The average BM LA level across the world, including mainland China, is below the maximum 28% FA, and no toxicological or long-term safety data are available on LA levels &gt; 28% FA. Although recommended IF LA/ALA ratios range from 5:1 to 15:1, ratios closer to 5:1 seem to promote a higher endogenous synthesis of DHA. However, even those infants fed IF with more optimal LA/ALA ratios do not reach the DHA levels observed in breastfed infants, and the levels of DHA present are not sufficient to have positive effects on vision. Current evidence suggests that there is no benefit to going beyond the maximum LA level of 28% FA in IF. To achieve the DHA levels found in BM, the addition of DHA to IF is necessary, which is in line with regulations in China and the EU. Virtually all intervention studies investigating LA levels and safety were conducted in Western countries in the absence of added DHA. Therefore, well-designed intervention trials in infants across the globe are required to obtain clarity about optimal and safe levels of LA and LA/ALA ratios in IF.

Trans-Hydroxy, Trans-Epoxy, and Erythro-dihydroxy Fatty Acids Increase during Deep-Frying.

Deep-frying of food is a common cooking technique causing thermal oxidation of fatty acids (FA). Here, we investigated for the first time the formation of hydroxy-, epoxy- and dihydroxy-FA derived from oleic, linoleic (LA), and α-linolenic acid (ALA) during frying. Potato chips were fried in high-oleic sunflower oil for 4 × 5 cycles on 2 days, and the oil was comprehensively analyzed by liquid chromatography-tandem mass spectrometry. During frying, the E,Z-9- and E,Z-13-hydroperoxy-LA and -ALA concentrations decrease while their corresponding hydroxy-FA remain constant. The concentrations of both E,E-9-/13-hydroperoxy-LA and E,E-9-/13-hydroxy-LA increase with the frying cycles, which is also found for the concentration of trans-epoxy-FA. The increase in trans-epoxy-FA is more pronounced than that of the corresponding cis-epoxy-FA, exceeding their concentrations on the second day of frying. This selective change in the cis-/trans-epoxy-FA ratio is also observed for their hydrolysis products: concentrations of erythro-dihydroxy-FA, derived from trans-epoxy-FA, increase during frying stronger than threo-dihydroxy-FA derived from cis-epoxy-FA. Based on these data, we suggest that the ratio of E,E-/E,Z-hydroxy-FA, in combination with the cis-/trans-epoxy-FA ratio, as well as the threo-/erythro-dihydroxy-FA ratio are promising new parameters to evaluate the heating of edible oils and to characterize the status of frying oils.

Anti-Inflammatory and Anti-Osteoclastogenesis Activities of Different Kinds of Zanthoxylum bungeanum Seed Oil in vitro.

Our previous study has exhibited that one kind of Zanthoxylum bungeanum seed oil (ZSO), extracted from Zanthoxylum bungeanum seed, had inhibitory effects on osteoclastogenesis. However, the anti-osteoclastogenesis activities of different kinds of ZSO are scarcely reported. Since inflammation is related to bone loss and osteoporosis, in this study, three kinds of ZSO, Zanthoxylum schinifolium Siebold et Zucc seed oil (ZSSO), Zanthoxylum armatum DC. seed oil (ZDSO) and Zanthoxylum bungeanum maximum seed oil (ZBSO), were obtained with Soxhlet extraction and their fatty acid constituents were detected by GC-FID. RAW264.7 macrophages induced by lipopolysaccharide (LPS) were used to evaluate the inhibitory effects of three kinds of ZSO on inflammation via detecting the expression levels of inflammatory factors by RT-qPCR. Moreover, RANKL-induced osteoclastogenesis was applied to demonstrate the anti-osteoclastogenesis activities of them through tartrate-resistant acid phosphatase (TRAP) staining and RT-qPCR. The GC-FID results exhibited that the highest constituent in ZSSO and ZDSO was oleic acid (OA) and palmitoleic acid (PLA), respectively. While linoleic acid (LA) and α-Linolenic acid (ALA) in ZBSO were dominant. At the concentration of 0.5 μL/mL, all three kinds of ZSO could decrease the expression levels of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1 beta (IL-1β) in LPS-induced macrophages. At the concentration of 0.25 μL/mL, only ZSSO could decrease the expression levels of iNOS and COX-2, which implied the inhibitory effects of ZSSO were stronger than other ZSOs. The number of RANKL-induced osteoclasts and the expressions of nuclear factor kappa-B (NF-κB), TNF-α and IL-6 in the cells were decreased after being treated with ZSOs at the concentration of 0.5 μL/mL, while the number of RANKL-induced osteoclasts after treated with ZBSO were less than those treated with other ZSOs, this indicated that the anti-osteoclastogenesis effect of ZBSO were stronger than other ZSOs. In conclusion, the fatty acid compositions of three major kinds of ZSO were compared and the content of unsaturated fatty acids especially ω-3 polyunsaturated fatty acids in ZBSO were the highest among them. All ZSOs tested had anti-inflammatory and anti-osteoclastogenesis activities. And their anti-osteoclastogenesis effects might be related to thesuppression of the NF-κB pathway.

Plant-based meat substitutes are useful for healthier dietary patterns when adequately formulated - an optimization study in French adults (INCA3).

We studied to what extent plant-based meat substitutes could improve the nutritional adequacy and healthiness of dietary patterns, depending on their nutrient composition. From diets observed in French adults (INCA3, n = 1125), modeled diets were identified by allowing various dietary changes, between and within food categories, when two plant-based meat substitutes were made available: an average substitute (from 43 market substitutes) and a theoretical nutritionally designed substitute, fortified or not with zinc and iron at 30% or 50% of Nutrient Reference Values. Under each scenario, healthier but acceptable modeled diets were identified using multi-criteria optimization, by maximizing a health criteria related to Dietary Guidelines while minimizing deviation from the observed diets, under constraints for nutrient adequacy. Without fortification, the average substitute was hardly introduced into modeled diets, whereas the optimized substitute was preferentially introduced, in large amounts, yet together with a moderate reduction of red meat (-20%). The comparative advantages of the optimized substitute were its higher contribution to vitamins B6 and C, fiber and α-linolenic acid (ALA) intakes, and its lower contribution to sodium intake. When fortified with iron and zinc, substitutes were introduced in larger amounts into modeled diets, with much higher red meat reductions (down to -90%). The optimized substitute continued to be preferred, leading to healthier modeled diets that deviated less from the observed. Plant-based meat substitutes can be levers for healthy diets only when well nutritionally designed with enough zinc and iron for a substantial red meat reduction.