Alpha-Linolenic Acid-Enriched Diacylglycerol Oil Suppresses the Postprandial Serum Triglyceride Level—A Randomized, Double-Blind, Placebo-Controlled, Crossover Study

Oxylipin profiling analyses reveal that ω-3 PUFA is more susceptible to lipid oxidation in sheep testis under oxidative stress

Reactive oxygen species causes oxidative stress, which oxidizes polyunsaturated fatty acids (PUFAs) to form oxidative metabolites. Sertoli cell is an important cellular metabolism of PUFA in testicular cells, and it regulates the testis development and spermatogenesis. However, the oxylipins generated in testes with different developmental statuses are lacking. In this study, twelve 6-month-old Hu sheep were selected and divided into large testicular group (L) and the small testicular group (S) (n=6). UPLC-MS/MS was conducted to screen oxylipins in the testis, and the total oxylipin and ω-3 PUFA-derived oxylipin contents in the S group were higher. A total of 20 differential oxylipins between the two groups were screened. Among them, the contents of ω-3 PUFA, DHA-derived oxylipins were increased in the S group. The arachidonic acid-derived oxylipin was lower in the S group. The mRNA expression levels of genes related to oxylipin regulation (AKR1B1, PTGER2, and PTGDS) were higher in the S group (P < 0.05). In vitro, 200 µM α-linolenic acid alleviated oxidative stress damage to Sertoli cells and improved cell viability by increasing the superoxide dismutase contents and mRNA expression levels of GPX4 and Bcl2. These results indicate that ω-3 PUFA is more susceptible to lipid oxidation in the S group under oxidative stress, which might alleviate the damage of oxidative stress to testis. Moreover, ALA could stimulate the proliferation of Sertoli cells by increasing the capacity of antioxidants. This work may provide a theoretical basis for further studies on the antioxidant properties of the testis for Hu sheep.

Comparative Lipidomics Analysis of Human and Ruminant Milk Reveals Variation in Composition and Structural Characteristics

In the present study, the different lipidomes between human milk and ruminant milk were compared. The 471, 376, 467, and 87 differential lipids were identified in human versus cow, goat, sheep, and camel groups, respectively. According to multivariate statistical analysis, lipids in human and camel milk were closer but differed from other milk. The distributions of long-chain and polyunsaturated fatty acids of triglycerides (TGs), the proportions of functional TGs (OPO, OPL, and PPO), and many kinds of phospholipids (PLs) (PS, PI, GD, GM3, and Cer) in human milk were similar to those in camel milk. The similar structure of TGs and proportion of PLs in human milk to camel milk might contribute to their similar digestion and bioactivity properties. Camel milk could be considered as a new resource of lipid base for infant formula. Minor PLs should also be considered for designing formula. Our results provide a new sight for humanized lipids in infant formula.

Perilla frutescens seed oil combined with Anredera cordifolia leaf powder attenuates age-related cognitive decline by reducing serum triglyceride and glucose levels in healthy elderly Japanese individuals: a possible supplement for brain health

We have shown that Anredera cordifolia extract improves learning and memory in a senescence-accelerated mouse model, and that α-linolenic acid (ALA)-rich Perilla frutescens seed oil (PO) improves brain function in healthy Japanese adults and elderly individuals. Herein, we present a 12-month, randomised, double-blind, parallel-armed intervention trial examining the effects of PO supplementation alone or in combination with A. cordifolia leaf powder on brain function in healthy elderly Japanese individuals. Participants were randomly divided into two groups: the PO group received 1.47 mL PO (0.88 g ALA) daily via soft gelatine capsules, and the POAC group received 1.47 mL PO and 1.12 g A. cordifolia leaf powder (1.46 mg vitexin and 1.12 mg adenosine) daily. After 12 months of intervention, the POAC group showed generally higher cognitive index scores than the PO group. The beneficial effects of combined supplementation on cognitive function were associated with increased ALA and eicosapentaenoic acid levels in red blood cell plasma membranes, increased serum biological antioxidant potential, and decreased serum triglyceride, glucose, and N-(epsilon)-carboxymethyl-lysine (CML), an advanced glycation end-product and biochemical marker of oxidative stress levels. The effects of combined supplementation on cognitive function also showed a significant negative correlation with serum CML levels after 12 months of intervention. Our findings suggest that combined long-term supplementation with PO and A. cordifolia more effectively ameliorates age-related cognitive decline than PO alone. These findings may serve as a basis for the development of new supplements for brain health. Clinical Trial Registry, UMIN000040863.

The review of alpha-linolenic acid: Sources, metabolism, and pharmacology

α-linolenic acid (ALA, 18:3n-3) is a carboxylic acid composed of 18 carbon atoms and three cis double bonds, and is an essential fatty acid indispensable to the human body. This study aims to systematically review related studies on the dietary sources, metabolism, and pharmacological effects of ALA. Information on ALA was collected from the internet database PubMed, Elsevier, ResearchGate, Web of Science, Wiley Online Library, and Europe PMC using a combination of keywords including "pharmacology," "metabolism," "sources." The following findings are mainly contained. (a) ALA can only be ingested from food and then converted into eicosapentaenoic acid and docosahexaenoic acid in the body. (b) This conversion process is relatively limited and affected by many factors such as dose, gender, and disease. (c) Pharmacological research shows that ALA has the anti-metabolic syndrome, anticancer, antiinflammatory, anti-oxidant, anti-obesity, neuroprotection, and regulation of the intestinal flora properties. (d) There are the most studies that prove ALA has anti-metabolic syndrome effects, including experimental studies and clinical trials. (e) The therapeutic effect of ALA will be affected by the dosage. In short, ALA is expected to treat many diseases, but further high quality studies are needed to firmly establish the clinical efficacy of ALA.

Consumption of alpha-linolenic acid-enriched diacylglycerol induces increase in dietary fat oxidation compared with alpha-linolenic acid-enriched triacylglycerol: A randomized, double-blind trial

Fat metabolism is an important consideration in obesity. Alpha-linolenic acid-enriched diacylglycerol (ALA-DAG), which mainly occurs as ALA esterifies to 1,3-diacyl-sn-glycerol (1,3-DAG), has beneficial effects on fat metabolism and body weight compared with triacylglycerol (TAG). Moreover, compared with ALA-TAG, ALA-DAG enhances β-oxidation activity in the small intestine and liver in rodents. We hypothesized that ALA-DAG consumption may increase dietary fat oxidation compared with ALA-TAG in humans. To examine this hypothesis, we conducted a randomized double-blind cross-over trial in 17 normal and moderately obese men and women (BMI: 25.7±2.0 kg/m², mean±SD). Each participant was assigned to a 4-week intervention period with 2.5 g/day of ALA-DAG or ALA-TAG consumption, followed by a 4-week washout period between consumption of each diet. Dietary fat oxidation, assessed based on the ¹³CO₂ recovery rate in the breath, was significantly increased by ALA-DAG consumption compared with ALA-TAG consumption (17.0±4.5% and 14.1±5.9%, respectively, P<.05). In addition, ALA-DAG consumption significantly decreased the visceral fat area compared with ALA-TAG (102.9±51.9 cm² and 110.9±51.7 cm², respectively; P<.05). These results indicate that ALA-DAG consumption may be useful for preventing obesity.