Consumption of Interesterified Medium- and Long-Chain Triacylglycerols Improves Lipid Metabolism and Reduces Inflammation in High-Fat Diet-Induced Obese Rats

IgD-CD38-B Cell Partially Mediates the Protective Effect of Higher Serum Triacylglycerol (53:4) Levels Against Parkinson's Disease

Emerging evidence suggests that dysregulated lipid metabolism contributes to Parkinson's disease (PD) risk, with chronic inflammation in the central nervous system (CNS) also playing a pivotal role. Although correlations between inflammatory responses, serum lipid metabolism, and PD risk are established, a causal relationship remains unclear. Building on previous findings linking higher serum triacylglycerol (51:4) levels to reduced PD risk, this study explores the potential causal associations between 38 triacylglycerol isoforms and PD risk using Mendelian randomization (MR). We utilized summary-level data from genome-wide association studies (GWAS) on PD, circulating immune cells, inflammatory proteins, and serum lipidomes-including 38 triacylglycerol isoforms, 15 sterol ester isoforms, and 46 phosphatidylcholine isoforms-to assess the relationship between serum lipid profiles and PD. Our analysis revealed that higher levels of serum triacylglycerol (51:4) and triacylglycerol (53:4) were associated with a reduced PD risk, whereas lower levels of phosphatidylcholine (17:0_18:1) and sterol ester (27:1/20:2) were linked to higher PD risk. Notably, multivariable MR analysis confirmed a robust causal association between increased serum triacylglycerol (53:4) and a 24% reduction in PD risk (1 SD higher triacylglycerol (53:4) leading to a 24% [95% CI, 0.54-0.97] risk reduction, p = 0.005). Mediation analysis suggested that circulating immune cells, rather than inflammatory proteins, may mediate the relationship between triacylglycerol (53:4) levels and PD risk. These findings establish a causal link between triacylglycerol (53:4) and PD risk, highlighting the potential role of immune modulation in PD pathogenesis.

Innovative applications of medium- and long-chain triacylglycerol in nutritional support: Current perspectives and future directions

As a unique structured lipid, medium- and long-chain triacylglycerol (MLCT) is characterized by the combination of medium- and long-chain fatty acids in a single triacylglycerol molecule. In recent years, MLCT, as a nutritional lipid, has gradually emerged as a research hot topic in the fields of food science and nutrition. This paper innovatively provides a comprehensive review of the current application status and development prospects of MLCT in nutritional support. First, the basic principles defining characteristics and selection basis of both enteral and parenteral nutrition are analyzed, elucidating the differences between the two modalities in terms of nutrient delivery pathway, absorption mechanisms, and physiological effects. Subsequently, the natural sources and artificial synthetic pathways of MLCT along with its metabolic behavior in vivo are elaborated. On this basis, the latest research advancements in the application of MLCT in both nutritional models are reviewed, with a particular emphasis on current research hotspots. Finally, the challenges encountered in the practical application of MLCT are discussed, and the future trajectory of MLCT as a functional lipid is predicted. In particular, the innovative potential of MLCT in functional foods, food for special medical purposes, personalized nutrition, and other aspects is emphasized, which provides beneficial ideas and directions for further research and industrial applications of MLCT.

A Comprehensive Investigation of Lipid Profile During the Solid-State Fermentation of Rice by Monascus purpureus

Red yeast rice is a nutraceutical fermented product used worldwide for the symptomatic relief of dyslipidemia and cardiovascular disease. However, the fermentation-induced lipid transformation from rice to red yeast rice remains unclear. Herein, an ultra-high performance liquid chromatography coupled with hybrid quadrupole-orbitrap mass spectrometry method was developed for the comprehensive lipid analysis during fermentation. A total of 246 lipids fall in 21 subclasses were annotated in rice and red yeast rice, including 37 lysophospholipids, 14 phospholipids, 29 diglycerides, 114 triglycerides and fatty acid (15 species), ceramide (12 species), hexosylceramide (3 species), sitosterol ester (2 species), monogalactosyldiacylglycerol (2 species), digalactosyldiacylglycerol (2 species), monogalactosylmonoacylglycerol (8 species), digalactosylmonoacylglycerol (5 species), coenzyme Q (1 species), acyl hexosyl campesterol ester (1 species), and acylcarnitine (1 species). Results showed that lipid profiles changed, and new lipid species emerged. Notably, 18 medium- and long-chain triacylglycerols and triacylglycerols with short-chains were tentatively identified. These triacylglycerols also show the effects of body fat accumulation reduction, and hypolipidemic and hypoglycemic activities. Furthermore, lipid species that were profoundly changed were quantified, and the dynamic changes were investigated. This study clarified the molecular species and compositional changes in fermented rice from lipid aspect.

Could New Palm-Free Structured Lipids Mitigate Postprandial Hyperlipidemia and Inflammation Induced by High-Fat Meals in Swiss Mice?

A high-fat meal can cause postprandial hyperlipemia, initiating an acute inflammatory response. New structured lipids (SLs) free from trans and palm fatty acids are emerging as food structurants.

Objective: We evaluated the postprandial response and inflammatory profiles in Swiss mice after oral administration of SLs in high-fat meals.

Methods: SLs with different contents of long-chain saturated fatty acids were synthesized through an interesterification process involving soybean, peanut oils and crambe hard fat.

Results: SLs containing 23.79% (SL1), 32.01% (SL2), and 43.87% (SL3) of total saturated fatty acids reduced the absorption of serum triglycerides and appeared to mitigate postprandial inflammation by interleukin-6. A faster gastric emptying rate after consuming SL3 was corroborated by the fecal presence of behenic acid.

Conclusions: Our results suggest that SLs, free from palm and trans fats, may have the potential to mitigate inflammation, reduce the postprandial response, and lower absorption upon acute consumption.

Lauric-α-linolenic lipids modulate gut microbiota, preventing obesity, insulin resistance and inflammation in high-fat diet mice

Medium- and long-chain triacylglycerols (MLCTs) are regarded as healthy premium oils; however, the health benefits of novel MLCTs enriched with lauric and α-linolenic acids are still not fully understood. This study examined the health benefits of lauric-α-linolenic structural lipids (ALSL) and physical mixture (PM) with a similar fatty acid composition in mice with obesity induced by the high-fat diet (HFD). The data indicated that ALSL is more effective than PM in counteracting obesity, insulin resistance, hyperlipidaemia, liver injury, and systemic inflammation in HFD-induced mice. These effects may be associated with the regulation of gut microbiota. ALSL significantly upregulated the abundance of Dubosiella, Lactobacillus, and Bifidobacterium while reducing the abundance of Ileibacterium. Furthermore, ALSL therapy increased the levels of acetic acid, propionic acid, and total short-chain fatty acids. Correlation analysis found that the positive changes in these gut microbes correlated positively with the anti-inflammatory, insulin-sensitizing, and anti-obesity effects of ALSL.

A novel synthesis method of medium- and long-chain triglyceride lipids from rubber seed oil catalyzed by enzymatic interesterification and its metabolism mechanism

Medium- and long-chain triglyceride (MLCT) is a striking structural lipid for the supply of energy and essential fatty free acids (FFAs) in the food field. This study aimed to prepare MLCT by enzymatic interesterification of rubber seed oil (RSO) and medium-chain triglyceride (MCT). Fortunately, the conversion of synthesized MLCT could reach 75.4% by the catalysis of Novozym 40086 (7 wt% to MCT) at a temperature of 40 °C with the substrate mole ratio of 1 : 0.7 (RSO : MCT). The as-synthesized MLCT contained unsaturated fatty acid (USFA, 50.13%) at the sn-2 position and exhibited superior performance on the acid value, peroxide value and iodine value in contrast to grade III soybean oil. Moreover, it exhibited the simultaneous release of LCFAs and MCFAs, extremely facilitating the reduction of body weight gain and control of the level of lipids in the blood. Finally, the preferred hepatic metabolism process of the obtained MLCT was proven to be the main cause of the reduced body weight and improved lipid levels by the in vivo deposition experiments. Therefore, our study suggested that the outstanding performance of the MLCT synthesized by RSO in foods as functional lipids.

Encapsulation and characterization of ω-3 medium- and long-chain triacylglycerols microencapsulated with different proteins as wall materials

In this study, ω-3 medium- and long-chain triacylglycerols (MLCTs) microcapsules with excellent performance were obtained using soy protein as the wall component to address the oxidation-related problems of MLCTs. Additionally, the effect of soy, whey, or pea proteins on microcapsules in terms of the changes in their structure and physicochemical properties was investigated. The results showed that the small particle size, low PDI (polydispersity index) and zeta potential, fast adsorption rate, and low interfacial tension of these protein-based samples fabricated through the O/W template method were conducive to maintaining the integrity of microcapsules during spray-drying. The microcapsules, characterized by a spherical shape, exhibited superior encapsulation efficiency of 94.56%, surpassing the findings of previous investigations. Overall, these microcapsules exhibited long-term storage stability and low controllable release rates, which could be utilized as carriers for liposoluble actives.

Encapsulation and characterization of soy protein-based ω-3 medium- and long- chain triacylglycerols microencapsulated with diverse homogenization techniques for improving oxidation stability

Recently, MLCTs have attracted considerable attention as a potential alternative to traditional oils due to their suppressive effect on fat accumulation and insulin sensitivity. In this study, the microcapsules of MLCTs with superior performance were fabricated through different homogenization processes to overcome the limitations of ω-3 medium- and long- chain triacylglycerols (MLCTs), including poor stability and prone oxidation. Additionally, the impact of various homogenization techniques, namely, high-pressure, ultrasound, and cavitation jet, on the particle structure, encapsulation efficiency, and oxidation stability of microcapsules (MLCTs) was investigated. The MLCTs microcapsules fabricated through high-pressure homogenization had a smaller particle size of 295.12 nm, lower PDI of 0.24, and a higher zeta-potential absolute value of 32.65, which significantly improved their dispersion and encapsulation efficiency, reaching 94.56 % after the spray-drying process. Furthermore, the low moisture content and superior storage stability of MLCTs microcapsules have the potential to serve as carriers of liposoluble actives.

Novel Human Milk Fat Substitutes Based on Medium- and Long-Chain Triacylglycerol Regulate Thermogenesis, Lipid Metabolism, and Gut Microbiota Diversity in C57BL/6J Mice

Human milk is naturally rich in medium- and long-chain triacylglycerols (MLCT), accounting for approximately 30% of the total fat. However, infant formula fat is prepared using a physical blend of vegetable oils, which rarely contains MLCT, similar to human milk. The differences in MLCT between human milk and infant formulas may cause different lipid metabolisms and physiological effects on infants, which are unknown. This study aimed to analyze the metabolic characteristics of formula lipid containing novel human milk fat substitutes based on MLCT (FL-MLCT) and compare their effects with those of the physical blend of vegetable oils (FL-PB) on lipid metabolism and gut microbiota in mice. Compared with the FL-PB group, the FL-MLCT group showed increased energy expenditure, decreased serum triacylglycerol level, and significantly lower aspartate aminotransferase level, epididymal and perirenal fat weight, and adipocyte size. Moreover, the abundances of Firmicutes/Bacteroidota, Actinobacteriota, and Desulfovibrionaceae were significantly decreased in the FL-MLCT group. Novel human milk fat substitutes MLCT could inhibit visceral fat accumulation, improve liver function, and modulate the mice gut microbiota composition, which may contribute to controlling obesity.

Effect of substrate composition on physicochemical properties of the medium-long-medium structured triacylglycerol

BACKGROUND

Nutritional and functional qualities and applications of structured lipids (SL) depend on the composition and molecular structure of fatty acids in the glycerol backbone of triacylglycerol (TAG). However, the relationship between the substrate composition and physicochemical qualities of SL has not been revealed. The investigation aims to disclose the effect of substrate composition on the physicochemical properties of medium-long-medium structured lipids (MLM-SLs) by enzymatic interesterification of Lipozyme TLIM/RMIM.

RESULTS

The medium-long-chain triacylglycerol (MLCT) yield could reach 70.32%, including 28.98% CaLCa (1,3-dioctonyl-2-linoleoyl glyceride) and 24.34% CaOCa (1,3-didecanoyl-2-oleoyl glyceride). The sn-2 unsaturated fatty acid composition mainly depended on long-chain triacylglycerol (LCT) in the substrate. The increased carbon chain length and double bond in triacylglycerol decreased its melting and crystallization temperature. The balanced substrate composition of MCT/LCT increased the size and finer crystals. Molecular docking simulation revealed that the MLCT molecule mainly interacted with the catalytic triplets of Lipozyme TLIM (Arg81-Ser83-Arg84) and the Lipozyme RMIM (Tyr183-Thr226-Arg262) by OH bond. The oxygen atom of the ester on the MLCT molecule was primarily bound to the hydrogen of hydroxyl and amino groups on the binding sites of Lipozyme TLIM/RMIM. The intermolecular interplay between MLCT and Lipozyme RMIM is more stable than Lipozyme TLIM due to the formation of lower binding affinity energy.

CONCLUSION

This research clarifies the interaction mechanism between MLCT molecules and lipases, and provides an in-depth understanding of the relationship between substrate composition, molecular structure and physicochemical property of MLM-SLs. © 2023 Society of Chemical Industry.

Comparison of fresh and browning lotus roots (Nelumbo nucifera Gaertn.) on modulating cholesterol metabolism via decreasing hepatic cholesterol deposition and increasing fecal bile acid excretion

Lotus root (LR) is prone to browning after harvest due to the oxidation of phenolic compounds by polyphenol oxidase (PPO). This study compared the effects of LR extract and BLR extract on cholesterol metabolism in high-fat diet (HFD) mice. Our findings highlighted the innovative potentiality of BLR extract in effectively regulating cholesterol metabolism via inhibiting the intestinal FXR-FGF15 signaling pathway and boosting probiotics in gut microbiota, offering valuable insights for hypercholesterolemia and metabolic disorders. In detail, catechin was the main phenolic compound in LR, while after browning, theaflavin was the main oxidation product of phenolic compounds in BLR. Both the intake of LR extract and BLR extract regulated the disorder of cholesterol metabolism induced by HFD. In particular, BLR extract intake exhibited more robust effects on increasing the BAs contents synthesized in the liver and excreted in feces compared with LR extract intake. Furthermore, the consumption of BLR extract was more effective than that of LR extract in reducing the ileal protein expressions of FXR and FGF15 and shifting BAs biosynthesis from the classical pathway to the alternative pathway. Moreover, LR extract and BLR extract had distinct effects on the gut microbiota in HFD-fed mice: BLR extract significantly elevated probiotics Akkermansia abundance, while LR extract increased Lactobacillus abundance. Therefore, both LR extract and BLR extract improved the cholesterol deposition effectively and BLR extract even showed a stronger effect on regulating key gene and protein expressions of cholesterol metabolism.

Reduction of lauric acid content in virgin coconut oil improved plasma lipid profile in high-fat diet-induced hypercholesterolemic mice

Virgin coconut oil (VCO) is claimed to have various health benefits, but favorable effects of its major component (∼50%), lauric acid, are controversial. Therefore, we aimed to reduce lauric acid content (∼30%) in VCO and evaluate its effect compared to VCO and medium-chain triglycerides (MCT), on food intake, bodyweight (BW), lipid profiles, and hepatic histology. Female C57BL/6 mice were treated with different diets for 3 months: control (normal diet), high-fat diet (HF), HF + VCO, HF + MCT, HF + low lauric acid VCO (LLA), and normal diet + LLA (C + LLA). LLA was prepared by enzymatic interesterification of VCO with methyl octanoate (methyl caprylate) and methyl decanoate (methyl caprate). Plasma and liver lipids, including total cholesterol (TC), high-density lipoprotein (HDL), and triglyceride, were measured by colorimetric assay, and hepatic fat accumulation was examined by oil-red-O staining. HF mice exhibited high plasma and liver TC and low-density lipoprotein (LDL). VCO or MCT treatment lowered liver TC and LDL, whereas LLA increased plasma HDL and markedly improved TC:HDL ratio. The HF-induced hepatic fat accumulation was attenuated by all treatments, of which VCO was the most effective. Control mice administered with LLA demonstrated lower liver TC and LDL, but higher plasma TC and HDL compared to controls. Lowest BW gain and food intake were found in mice treated with LLA. In conclusion, VCO, MCT, and LLA ameliorated hepatic histopathology caused by HF. VCO and MCT improved liver lipid profiles, whereas LLA has more beneficial effect on plasma lipids via a better TC:HDL ratio and showed promise for BW control.

Bioimprinted lipase-catalyzed synthesis of medium- and long-chain structured lipids rich in docosahexaenoic acid for infant formula

Medium- and long-chain structured lipids (MLSLs) rich in docosahexaenoic acid (DHA) were obtained in shorter reaction time by acidolysis of single-cell oil (DHASCO) from Schizochytrium sp. with caprylic acid (CA) using a lipase bioimprinted with fatty acids as a catalyst. The conditions for preparation of the bioimprinted lipase for the acidolysis reaction were firstly optimized and the activity of the obtained lipase was 2.17 times higher than that of the non-bioimprinted. The bioimprinted lipase was then used as a catalyst and the reaction conditions were optimized. Under the optimal conditions, the equilibrium could be achieved in 4 h, and the total and sn-1,3 CA contents in the product were 29.18% and 42.34%, respectively, and the total and sn-2 DHA contents were 46.26% and 70.12%, respectively. Such MLSLs rich in sn-1,3 CA and sn-2 DHA are beneficial for DHA absorption, and thus have potential for use in infant formula.

Preparation of functional oils rich in diverse medium and long-chain triacylglycerols based on a broadly applicable solvent-free enzymatic strategy

To address the problems of long reaction times and limited range of adaptation in enzymatic synthesis medium- and long-chain triacylglycerols (MLCTs), a broadly applicable solvent-free enzymatic interesterification strategy was proposed. Candida sp. lipase (CSL) was immobilized on hydrophobic hollow mesoporous silica spheres (HHSS) to construct a biocatalyst designated as CSL@HHSS with a 15.3 % immobilization yield and a loading amount of 94.0 mg/g. The expressed activity and the specific activity were 20.14 U/g and 173.62 U/g, which were 4.6 and 5.6 times higher than that of free CSL, respectively. This biocatalyst demonstrated higher activity, wider applicability, and excellent reusability. Linseed oil, sunflower oil, perilla seed oil, algal oil, and malania oleifera oil were applied as substrates to produce MLCTs with medium-chain triacylglycerols (MCT) catalyzed by CSL@HHSS through interesterification in yields ranging from 69.6 % to 78.0 % within 20 min. Specific fatty acids, including linolenic acid, oleic acid, DHA, and nervonic acid (the first reported), were introduced into MLCT's skeleton, respectively. The structures were finely analyzed and identified by GC and UPLC-MS. The catalytic efficiency value of CSL@HHSS in catalyzing interesterification between linseed oil and MCT (70 ℃, 20 min, lipase 6 wt%) is 0.86 g/g∙min, which is the highest ever reported. This paper presents an effective and sustainable strategy for functional MLCTs production.

Effects of the Novel LaPLa-Enriched Medium- and Long-Chain Triacylglycerols on Body Weight, Glycolipid Metabolism, and Gut Microbiota Composition in High Fat Diet-Fed C57BL/6J Mice

The roles of medium- and long-chain triacylglycerols (MLCT) on health benefits under high fat diet (HFD) conditions remain in dispute. This study was conducted to investigate the effects of novel LaPLa-rich MLCT on the glycolipid metabolism and gut microbiota in HFD-fed mice when pork fat is half replaced with MLCT and palm stearin (PS). The results showed that although MLCT could increase the body weight in the mouse model, it can improve the energy utilization, regulate the glucose and lipid metabolism, and inhibit the occurrence of inflammation. Furthermore, 16S rRNA gene sequencing of gut microbiota indicated that PS and MLCT affected the overall structure of the gut microbiota to a varying extent and specifically changed the abundance of some operational taxonomic units (OTUs). Moreover, several OTUs belonging to the genera Dorea, Streptococcus, and g_Eryipelotrichaceae had a high correlation with obesity and obesity-related metabolic disorders of the host. Therefore, it can be seen that this new MLCT has different properties and functions from the previous traditional MLCT, and it can better combine the advantages of MLCT, lauric acid, and sn-2 palmitate, as well as the advantages of health function and metabolism. In summary, this study explored the effects of LaPLa-enriched lipids on glycolipid metabolism in mice, providing theoretical support for future studies on the efficacy of different types of conjugated lipids, intending to apply them to industrial production and subsequent development of related products.

Salvia miltiorrhiza extract may exert an anti-obesity effect in rats with high-fat diet-induced obesity by modulating gut microbiome and lipid metabolism

BACKGROUND

Studies have shown that a high-fat diet (HFD) can alter gut microbiota (GM) homeostasis and participate in lipid metabolism disorders associated with obesity. Therefore, regulating the construction of GM with the balance of lipid metabolism has become essential for treating obesity. Salvia miltiorrhiza extract (Sal), a common traditional Chinese medicine, has been proven effective against atherosclerosis, hyperlipidemia, obesity, and other dyslipidemia-related diseases.

AIM

To investigate the anti-obesity effects of Sal in rats with HFD-induced obesity, and explore the underlying mechanism by focusing on GM and lipid metabolism.

METHODS

Obesity was induced in rats with an HFD for 7 wk, and Sal (0.675 g/1.35 g/2.70 g/kg/d) was administered to treat obese rats for 8 wk. The therapeutic effect was evaluated by body weight, body fat index, waistline, and serum lipid level. Lipid factors (cAMP, PKA, and HSL) in liver and fat homogenates were analyzed by ELISA. The effect of Sal on GM and lipid metabolism was assessed by 16S rRNA-based microbiota analysis and untargeted lipidomic analysis (LC-MS/MS), respectively.

RESULTS

Sal treatment markedly reduced weight, body fat index, serum triglycerides (TG), total cholesterol (TC), low-density lipoprotein, glucose, free fatty acid, hepatic lipid accumulation, and adipocyte vacuolation, and increased serum high-density lipoprotein (HDL-C) in rats with HFD-induced obesity. These effects were associated with increased concentrations of lipid factors such as cAMP, PKA, and HSL in the liver and adipose tissues, enhanced gut integrity, and improved lipid metabolism. GM analysis revealed that Sal could reverse HFD-induced dysbacteriosis by promoting the abundance of Actinobacteriota and Proteobacteria, and decreasing the growth of Firmicutes and Desulfobacterita. Furthermore, LC-MS/MS analysis indicated that Sal decreased TGs (TG18:2/18:2/20:4, TG16:0/18:2/22:6), DGs (DG14:0/22:6, DG22:6/22:6), CL (18:2/ 18:1/18:1/20:0), and increased ceramides (Cers; Cer d16:0/21:0, Cer d16:1/24:1), (O-acyl)-ω-hydroxy fatty acids (OAHFAs; OAHFA18:0/14:0) in the feces of rats. Spearman's correlation analysis further indicated that TGs, DGs, and CL were negatively related to the abundance of Facklamia and Dubosiella, and positively correlated with Blautia and Quinella, while OAHFAs and Cers were the opposite.

CONCLUSION

Sal has an anti-obesity effect by regulating the GM and lipid metabolism.

Aberrant hepatic lipid metabolism associated with gut microbiota dysbiosis triggers hepatotoxicity of novel PFOS alternatives in adult zebrafish

Perfluorooctane sulfonate (PFOS) has been reported to induce hepatotoxicity in wildlife and humans. Novel PFOS alternatives have been widely used following restrictions on PFOS, but little is known about their potential toxicity. Here, the first comprehensive investigation on the chronic hepatotoxicity and underlying molecular mechanisms of PFOS, 6:2Cl-PFESA (F-53B), and sodium p-perfluorous nonenoxybenzene sulfonate (OBS) was carried out on adult zebrafish through a histopathological examination, biochemical measurement, and multi-omics analysis. PFOS and its alternatives caused changes in liver histopathology and liver function indices in the order of F-53B > PFOS > OBS, which was consistent with their concentration in the liver. In silico modeling and transcriptional profiles suggested that the aberrant hepatic lipid metabolism induced by F-53B and PFOS was initiated by the action on peroxisome proliferator-activated receptor γ (PPARγ), which triggered changes in downstream genes transcription and led to an imbalance between lipid synthesis and expenditure. Gut microbiome analysis provided another novel mechanistic perspective that changes in the abundance of Legionella, Ralstonia, Brevundimonas, Alphaproteobacteria, Plesiomonas, and Hyphomicrobium might link to alterations in the PPAR pathway based on their significant correlation. This study provides insight into the molecular mechanisms of hepatotoxicity induced by PFOS and its novel alternatives and highlights the need for concern about their environmental exposure risks.

Anti-obesity effects of Laminaria japonica fucoidan in high-fat diet-fed mice vary with the gut microbiota structure

Previous studies have indicated that fucoidan could resist high-fat-diet (HFD)-induced obesity by modulating the composition of gut microbiota. However, the outcome of dietary intervention may differ between individuals due to large inter-individual variability in gut microbiota. Thus, the present study aimed to investigate the possible discrepancy of the anti-obesity effects of fucoidan supplementation in HFD-fed mice models with different gut microbiota communities. In the present study, the anti-obesity effects of fucoidan isolated from Laminaria japonica (FucLj) on normal mice and microbiota-altered mice treated with penicillin or metronidazole were compared and investigated. The 16S rRNA sequencing revealed the differences of gut microbiota among penicillin-treated, metronidazole-treated and normal groups, and mice treated with penicillin were characterized by greater relative abundance of the phylum Bacteroidetes and the families Muribaculaceae and Bacteroidaceae. Furthermore, FucLj ameliorated HFD-induced body weight gain, fat accumulation, serum lipid profiles, insulin resistance, hepatic steatosis and adipocyte hypertrophy in penicillin-treated and untreated mice, while no effects were observed in metronidazole-treated mice. Overall, mice with different initial gut microbiota responded differently to FucLj supplementation on a high-fat diet, and metronidazole-sensitive gut bacteria negatively correlated with obesity symptoms and were required for the anti-obesity effects of FucLj. Moreover, the anti-obesity effects were not dependent on the utilization of FucLj by gut microbiota to produce SCFAs. These findings indicate that evaluation of the gut microbiota structure before dietary interventions is helpful for enhancing the beneficial outcomes of dietary fiber supplementation and provide a rationale for the further application of dietary fucoidan in a personalized way.

Lauric Triglyceride Ameliorates High-Fat-Diet-Induced Obesity in Rats by Reducing Lipogenesis and Increasing Lipolysis and β-Oxidation

Medium-chain triglycerides (MCTs) are found in limited foods. In these medium-chain oil resources, the abundance of lauric acid (LA) is the highest among medium-chain fatty acids (MCFAs), and its effects on lipid metabolism in obese rats have not been well-studied. This study aimed to determine the anti-obesity effects and mechanisms of lauric triglyceride (LT) in Sprague Dawley (SD) rats. LA and glycerin were used to synthesize LT, then LT was used to treat obese rats for 12 weeks. The results showed that LT significantly reduced the body weight, body mass index, and Lee's index in obese rats. The mRNA expression levels of the anorexic neuropeptide POMC in the hypothalamus between the LT group and the other groups were not different, while the gene expression levels of the orexigenic neuropeptides NPY and AGRP decreased significantly in the LT group. Except serum cholesterol, LT improved the serum triglyceride metabolism in the obese rats and reduced adipocyte and hepatic lipid deposition. Moreover, LT inhibited the expression of lipogenesis-related genes and proteins (SREBP-1c, ACC1, and FASN) and increased the expression of lipolysis (ATGL, HSL, and LPL) and β-oxidation (PPARα, CPT-1a, and PCG-1α) related genes and proteins in the white fat and liver. Furthermore, LT increased the mRNA expression of mitochondrial-biosynthesis-related genes (SIRT1, NRF1, and TFAM) in the liver. The results indicated that LT ameliorates diet-induced obesity in rats.

Omega-7 Mixed Fatty Acid Supplementation Fails to Reduce Serum Inflammatory Biomarkers: A Placebo-Controlled, Double-Blind Randomized Crossover Trial

We report the effects of mixed omega-7 fatty acid supplementation on changes in serum hsCRP, TNFα, and IL-6 levels and self-reported outcomes in people with non-specific chronic musculoskeletal discomfort. Design: A double-blind, placebo-controlled, 1:1 randomized single crossover trial composed of 688 mg/day palmiteolate for the verum and an equivalent amount of medium-chain triglycerides for the placebo. Method: Data were analyzed in two independent groups and as a crossover group. Results: From 211 screened participants in 2017–2019, 56 were randomized. Six participants dropped out and fifty completers contributed to the statistical analyses. At baseline, none of the investigated biomarkers were significantly correlated to subjectively assessed musculoskeletal discomfort levels. For the two-group analysis (n = 26 and n = 24), none of the serum biomarkers reached statistical significance; however, a statistically significant placebo effect was found in the subjective outcomes. Conclusion: For the crossover analysis (n = 50), three weeks of supplementation with n7FA containing 688 mg per day of palmiteolate did not reduce serum inflammatory biomarkers nor did it improve subjectively measured quality of life (QoL) compared to placebo. Future studies should explore appropriate biomarkers, sufficient power, length of dosing, inclusion criteria for volunteers with higher BMI, and the verification of cis-palmiteolate versus trans-palmiteolate.

Effects of Miao sour soup on hyperlipidemia in high-fat diet-induced obese rats via the AMPK signaling pathway

Hyperlipidemia is a common characteristic of obese animals. Identifying the factors involved in the regulation of dietary lipid metabolism is the most beneficial way to improve health. Miao sour soup (MSS) is a fermented food made from tomato and red pepper that contains lycopene, capsaicin, and organic acids. We conducted this study to investigate the regulatory functions and mechanisms of MSS on the blood lipid levels of high-fat diet-induced obese rats. In our preventive study, rats were fed normal diet (ND1), high-fat diet (HFD1), HFD + 4 g/kg BW MSS (HFD + LS1), and HFD + 8 g/kg BW MSS (HFD + HS1). We found that MSS significantly reduced the body weight and fat accumulation and improved the blood lipid levels of rats. MSS significantly increased the expression of AMP-activated protein kinase-alpha (AMPKα), attenuated the expression of the adipogenic transcription factor sterol regulatory element-binding protein-1c (SREBP-1c), and suppressed the expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase alpha (ACCα), the critical regulators of hepatic lipid metabolism. Additionally, we also conducted a treatment study, and we grouped rats to receive ND2, HFD2, PC2, HFD + LS2, and HFD + HS2 for another 10 weeks. MSS treatment reduced the body weight, fat deposition, and percentage of lipid droplets and regulated the plasma lipid content. MSS significantly increased the expression of AMPK and alleviated the expression of SREBP-1c, ACC, and FAS. Taken together, these findings suggest that MSS prevents and treats hyperlipidemia in obese rats by regulating the AMPK signaling pathway.

Flavonoids from Whole-Grain Oat Alleviated High-Fat Diet-Induced Hyperlipidemia via Regulating Bile Acid Metabolism and Gut Microbiota in Mice

A high-fat diet (HFD) causes hyperlipidemia, which worsens disturbances in bile acid (BA) metabolism and gut microbiota. This study aimed to investigate the regulation of flavonoids from whole-grain oat (FO) on BA metabolism and gut microbiota in HFD-induced hyperlipidemic mice. The experiment results showed that FO improved serum lipid profiles and decreased body weight and lipid deposition in HFD-fed mice. Through real-time qualitative polymerase chain reaction (RT-qPCR) and Western blot assays, by up-regulating the expression of PPARα, CPT-1, CYP7A1, FXR, TGR5, NTCP, and BSTP, and down-regulating those of SREBP-1c, FAS, and ASBT, FO suppressed lipogenesis, promoted lipolysis and BA synthesis, and efflux to faeces via the FXR pathway. 16s rRNA sequencing revealed that FO significantly increased Akkermansia and significantly decreased Lachnoclostridium, Blautia, Colidextribacter, and Desulfovibrio. Spearman's correlation analysis showed that these bacteria were strongly correlated with hyperlipidemia-related parameters. Therefore, our results indicated that FO possessed an antihyperlipidemic effect via regulating the gut-liver axis, i.e., BA metabolism and gut microbiota.

High Dietary Intervention of Lauric Triglyceride Might be Harmful to Its Improvement of Cholesterol Metabolism in Obese Rats

Hypercholesterolemia is often considered to be a major risk factor for atherosclerosis, and medium-chain fatty acids have been found to reduce the total cholesterol (TC) level and maintain low-density lipoprotein cholesterol (LDL-c) stability. However, we unexpectedly found that the levels of TC and LDL-c were increased in obese rats treated with high-dose lauric triglycerides (LT). The study aimed to investigate the effect and mechanism of LT on cholesterol metabolism in obese rats. Our results showed that LT intervention could reduce cholesterol biosynthesis by downregulating the expression of HMG-CoA reductase in obese rats. LT increased the expression levels of PPARγ1, LXRα, ABCA1, and ABCG8 in the liver. These results indicated that LT could improve the lipid transfer and bile acid efflux. However, LT significantly increased the expression of PCSK 9, resulting in accelerated degradation of LDLR, thus reducing the transport of very LDL (VLDL) and LDL to the liver. Together with the increased expression of NPC1L1 protein, LT impaired the uptake of VLDL/LDL by the liver and increased the reabsorption of sterols, leading to an increase in the levels of TC and LDL-c in obese rats.

Efficient Synthesis of Structured Phospholipids Containing Short-Chain Fatty Acids over a Sulfonated Zn-SBA-15 Catalyst

Catalytic production of structured phospholipids (SPLs) containing short-chain fatty acids (SCFAs) in an efficient heterogeneous manner is of great importance from the standpoint of food engineering. Herein, a bifunctionalized sulfonated Zn-SBA-15 catalyst was studied for SPL synthesis through interesterification of soybean lecithin with ethyl propionate or methyl butyrate. Various characterization techniques such as pyridine Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and ultraviolet-visible diffuse reflectance spectroscopy were conducted to determine the physicochemical properties, so as to build the possible structure-reactivity relationship of the catalyst. In screening tests with commercial Amberlyst-15 or other SBA-15-type materials, the as-prepared sample showed promising catalytic performance probably owing to its mesoporous structure and cooperative role of Brönsted and Lewis acid sites. Notably, the sample was easily separated and recycled without obvious deactivation. In general, the investigated catalyst was regarded as one of the promising alternatives to otherwise expensive biocatalysts for SCFA-containing SPL production.