Chlorella unsaturated fatty acids suppress high-fat diet-induced obesity in C57/BL6J mice

Chlorella has been identified as a rich source of unsaturated fatty acids. Since the antiobesity effects of unsaturated fatty acids have been well documented; therefore, we explored the antiobesity actions of chlorella unsaturated fatty acids (C.UFAs) in the current study. The obtained results demonstrated C.UFAs, which contain abundant linoleic acid, could retard body weight gain (reducing body weigh by 13.93% after 16 weeks of treatment), improve blood glucose (19.29% lower) and lipid profile (23.45% lower in TG, 8.76% lower in TC) compared to high-fat diet-fed C57BL/6J mice. The possible underlying mechanisms might involve reducing hepatic lipid accumulation via down-regulation of lipogenic genes (PPARγ, C/EBPα, LPL, aP2, FAS, and SREBP-1c) and up-regulation of lipolytic gene (adiponectin). We also demonstrate C.UFAs could reduce HFD-induced adipocyte hypertrophy via activation of AMPK signaling pathway in adipose tissue and liver. In summary, our study highlights the potential of C.UFAs as a functional food for obesity management. PRACTICAL APPLICATION: Chlorella has already been commercialized as a functional food antiobesity function. In the current study, the unsaturated fatty acids isolated from chlorella were found to exert beneficial effects on hyperglycemia, hyperlipidemia, hepatic steatosis, and adipocyte hypertrophy in high-fat diet-fed mice. This may provide theoretical foundation for developing novel chlorella-based functional foods.

A novel n-3 glyceride mixture enhances enrichment of EPA and DHA after single dosing in healthy older adults: results from a double-blind crossover trial

A glyceride mixture of monoglyceride, diglyceride and TAG increases solubilisation and enhances emulsification of n-3 fatty acid (FA)-containing lipids in the stomach. This allows for better access of digestive enzymes, pivotal for the release of bioactive n-3 FA. The objective was to compare the effect of a glyceride formulation and an ethyl ester formulation of EPA + DHA on concentrations of EPA and DHA in plasma following single dosing. We conducted a double-blind crossover trial in which twenty healthy adults aged 50-70 years consumed a single dose (2·8 g EPA + DHA) of each EPA + DHA formulation without a meal in random order separated by a 2-week washout period. EPA and DHA were measured in plasma total lipid over the following 12 h. EPA and DHA in plasma total lipid increased over 12 h with both formulations. A 10-fold greater Δ concentration of EPA, 3-fold greater Δ concentration of DHA and 5-fold greater Δ concentration of EPA + DHA were seen with the glyceride-EPA + DHA. The time at which the maximal concentrations of n-3 FA occurred was 4 h earlier for EPA, 1 h earlier for DHA and 2 h earlier for EPA + DHA when consuming glyceride-EPA + DHA. A mixture of monoglyceride, diglyceride and TAG results in greater and faster incorporation of EPA and DHA into blood plasma lipid in the absence of a fatty meal. This may provide benefit to individuals on a low-fat diet or with digestive impairments and could result in greater efficacy in clinical trials using n-3 FA.

Effect of Dietary Oil Rich in Docosahexaenoic Acid-Bound Lysophosphatidylcholine Prepared from Fishery By-Products on Lipid and Fatty Acid Composition in Rat Liver and Brain

The possibility of improving brain function coupled with its preferential uptake in the brain has garnered attention for docosahexaenoic acid-bound lysophosphatidylcholine (DHA-LPC). However, studies focusing on the health benefits of dietary DHA-LPC are lacking. We prepared a dietary oil rich in DHA-LPC (DHA-LPC rich oil) via enzymatic modification of phospholipids (PL) extracted from squid (Todarodes pacificus) meal and purification of active carbon, ion exchange resin, and silica gel. We then examined the effects of dietary DHA-LPC rich oil on male Wistar rats by evaluating serum and liver lipid profiles, fatty acid (FA) metabolizing enzyme activity, and the FA composition of serum and brain. The rats were fed a basal diet containing either soybean oil alone (7%) or soybean oil (4.5%) with DHA-LPC rich oil (2.5%) for 28 days, and then evaluated. The rats fed the diet containing DHA-LPC rich oil showed reduced triacylglycerol concentration due, in part, to the enhancement of carnitine palmitoyltransferase 2 and acyl-CoA oxidase activities and suppression of acetyl-CoA carboxylase and glucose-6-phosphate dehydrogenase activities in the liver. Moreover, the dietary DHA-LPC rich oil moderately increased DHA in the FA composition of the rat hippocampus, which may be due to elevated DHA composition in serum LPC. These results suggest that DHA-LPC rich oil has hypolipidemic effect and moderate increase in hippocampal DHA amount in normal rats.

Multiscale structures of lipids in foods as parameters affecting fatty acid bioavailability and lipid metabolism

On a nutritional standpoint, lipids are now being studied beyond their energy content and fatty acid (FA) profiles. Dietary FA are building blocks of a huge diversity of more complex molecules such as triacylglycerols (TAG) and phospholipids (PL), themselves organised in supramolecular structures presenting different thermal behaviours. They are generally embedded in complex food matrixes. Recent reports have revealed that molecular and supramolecular structures of lipids and their liquid or solid state at the body temperature influence both the digestibility and metabolism of dietary FA. The aim of the present review is to highlight recent knowledge on the impact on FA digestion, absorption and metabolism of: (i) the intramolecular structure of TAG; (ii) the nature of the lipid molecules carrying FA; (iii) the supramolecular organization and physical state of lipids in native and formulated food products and (iv) the food matrix. Further work should be accomplished now to obtain a more reliable body of evidence and integrate these data in future dietary recommendations. Additionally, innovative lipid formulations in which the health beneficial effects of either native or recomposed structures of lipids will be taken into account can be foreseen.