Anti-obesity potential of a yogurt functionalized with a CLNA-rich pomegranate oil.

Pomegranate oil is rich in conjugated linolenic acids, compounds which have attracted attention due to their potential applicability in obesity management as they are capable of modulating leptin and adiponectin secretion and regulate fatty acids storage and glucose metabolism. Among the possible bioactive foodstuffs capable of delivering these bioactive compounds yogurts have shown potential. Thus, the purpose of this work was to develop functional yogurts through the addition of pomegranate oil either in its free or encapsulated (used as a protective strategy against oxidation and gastrointestinal tract passage) forms. To that end, the pomegranate oil (free and encapsulated) was incorporated in yogurt and the functional yogurt capacity to modulate hepatic lipid accumulation, adipocyte metabolism (in terms of lipolysis, and adipokines secretion) and immune response was evaluated. The results obtained showed that the pomegranate oil's incorporation led to an improvement in the yogurts' nutritional values, with a reduction in its atherogenic and thrombogenic indexes (more than 78% for atherogenic and 76% for thrombogenic index) and an enhancement of its hypocholesterolemic/hypercholesterolemic ratio (more than 62%) when compared to the control yogurt. Furthermore, data also showed for the first time how these functional yogurts promoted modulation of metabolic processes post GIT as they were capable of reducing by 40% triglycerides accumulation in steatosis-induced Hep G2 cells and by 30 % in differentiated adipocytes. Moreover, samples also showed a capacity to modulate the leptin and adiponectin secretion (56 % of increase in adiponectin) and reduce the IL-6 secretion (ca 44%) and TNF-α (ca 12%) in LPS-stimulated cells. Thus, the CLNA-rich yogurt here developed showed potential as a viable nutraceutical alternative for obesity management.

Understanding the Anti-Obesity Potential of an Avocado Oil-Rich Cheese through an In Vitro Co-Culture Intestine Cell Model.

Nowadays, with consumers' requirements shifting towards more natural solutions and the advent of nutraceutical-based approaches, new alternatives for obesity management are being developed. This work aimed to show, for the first time, the potential of avocado oil-fortified cheese as a viable foodstuff for obesity management through complex in vitro cellular models. The results showed that oleic and palmitic acids' permeability through the Caco-2/HT29-MTX membrane peaked at the 2h mark, with the highest apparent permeability being registered for oleic acid (0.14 cm/s). Additionally, the permeated compounds were capable of modulating the metabolism of adipocytes present in the basal compartment, significantly reducing adipokine (leptin) and cytokine (MPC-1, IL-10, and TNF-α) production. The permeates (containing 3.30 µg/mL of palmitic acid and 2.16 µg/mL of oleic acid) also presented an overall anti-inflammatory activity upon Raw 264.7 macrophages, reducing IL-6 and TNF-α secretion. Despite in vivo assays being required, the data showed the potential of a functional dairy product as a valid food matrix to aid in obesity management.

Differential Lipid Accumulation on HepG2 Cells Triggered by Palmitic and Linoleic Fatty Acids Exposure.

Lipid metabolism pathways such as ß-oxidation, lipolysis and, lipogenesis, are mainly associated with normal liver function. However, steatosis is a growing pathology caused by the accumulation of lipids in hepatic cells due to increased lipogenesis, dysregulated lipid metabolism, and/or reduced lipolysis. Accordingly, this investigation hypothesizes a selective in vitro accumulation of palmitic and linoleic fatty acids on hepatocytes. After assessing the metabolic inhibition, apoptotic effect, and reactive oxygen species (ROS) generation by linoleic (LA) and palmitic (PA) fatty acids, HepG2 cells were exposed to different ratios of LA and PA to study the lipid accumulation using the lipophilic dye Oil Red O. Lipidomic studies were also carried out after lipid isolation. Results revealed that LA was highly accumulated and induced ROS production when compared to PA. Lipid profile modifications were observed after LA:PA 1:1 (v/v) exposure, which led to a four-fold increase in triglycerides (TGs) (mainly in linoleic acid-containing species), as well as a increase in cholesterol and polyunsaturated fatty acids (PUFA) content when compared to the control cells. The present work highlights the importance of balancing both PA and LA fatty acids concentrations in HepG2 cells to maintain normal levels of free fatty acids (FFAs), cholesterol, and TGs and to minimize some of the observed in vitro effects (i.e., apoptosis, ROS generation and lipid accumulation) caused by these fatty acids.

Pomegranate Oil's Potential as an Anti-Obesity Ingredient.

In recent years, pomegranate oil has obtained more attention due to its content of conjugated linolenic acids and possible application in the prevention of many diseases. The purpose of this work was to evaluate the potential ability of pomegranate oil to modulate obesity-related metabolism and immune response using in vitro models. In this regard, pomegranate oil was characterized in terms of fatty acids profile, tocopherols and phytosterols, and antioxidant capacity. After evaluation of the safety profile, pomegranate oil's capacity to modulate obesity-related metabolism was evaluated through adipolysis and adipokines secretion quantification in 3T3-L1 differentiated adipocytes and hepatic lipid accumulation assay in Hep G2 hepatocytes. The immunomodulatory activity was evaluated in Caco-2 cells by quantification of pro-inflammatory cytokines IL-6, IL-8, and TNF-α. This oil showed high antioxidant capacity and was mainly composed of conjugated fatty acid, namely punicic acid. Its chemical composition was responsible for its capacity to reduce the lipid accumulation in Hep G2 cells and 3T3-L1 differentiated adipocytes. In short, pomegranate oil shows great potential for the development of functional foods and nutraceuticals targeting obesity.

Microbial Production of Conjugated Linoleic Acid and Conjugated Linolenic Acid Relies on a Multienzymatic System.

Conjugated linoleic acids (CLAs) and conjugated linolenic acids (CLNAs) have gained significant attention due to their anticarcinogenic and lipid/energy metabolism-modulatory effects. However, their concentration in foodstuffs is insufficient for any therapeutic application to be implemented. From a biotechnological standpoint, microbial production of these conjugated fatty acids (CFAs) has been explored as an alternative, and strains of the genera Propionibacterium, Lactobacillus, and Bifidobacterium have shown promising producing capacities. Current screening research works are generally based on direct analytical determination of production capacity (e.g., trial and error), representing an important bottleneck in these studies. This review aims to summarize the available information regarding identified genes and proteins involved in CLA/CLNA production by these groups of bacteria and, consequently, the possible enzymatic reactions behind such metabolic processes. Linoleate isomerase (LAI) was the first enzyme to be described to be involved in the microbiological transformation of linoleic acids (LAs) and linolenic acids (LNAs) into CFA isomers. Thus, the availability of lai gene sequences has allowed the development of genetic screening tools. Nevertheless, several studies have reported that LAIs have significant homology with myosin-cross-reactive antigen (MCRA) proteins, which are involved in the synthesis of hydroxy fatty acids, as shown by hydratase activity. Furthermore, it has been suggested that CLA and/or CLNA production results from a stress response performed by the activation of more than one gene in a multiple-step reaction. Studies on CFA biochemical pathways are essential to understand and characterize the metabolic mechanism behind this process, unraveling all the gene products that may be involved. As some of these bacteria have shown modulation of lipid metabolism in vivo, further research to be focused on this topic may help us to understand the role of the gut microbiota in human health.

Milk fat components with potential anticancer activity-a review.

During many years, the milk fat has been unfairly undervalued due to its association with higher levels of cardiovascular diseases, dyslipidaemia or obesity, among others. However, currently, this relationship is being re-evaluated because some of the dairy lipid components have been attributed potential health benefits. Due to this, and based on the increasing incidence of cancer in our society, this review work aims to discuss the state of the art concerning scientific evidence of milk lipid components and reported anticancer properties. Results from the in vitro and in vivo experiments suggest that specific fatty acids (FA) (as butyric acid and conjugated linoleic acid (CLA), among others), phospholipids and sphingolipids from milk globule membrane are potential anticarcinogenic agents. However, their mechanism of action remains still unclear due to limited and inconsistent findings in human studies.

Absorption Kinetics of the Main Conjugated Linoleic Acid Isomers in Commercial-Rich Oil after Oral Administration in Rats.

This study aimed to assess the oral absorption and plasma kinetics of two main isomers contained in commercial conjugated linoleic acid (CLA)-rich oil (Tonalin TG-80), rumenic acid (RA), and C18:2 trans-10, cis-12. The isomer plasma disposition after the single oral dose of 3000 mg of Tonalin TG-80/kg, containing 1200 mg/kg of each isomer, was studied in rats. The isomer plasma concentrations were determined by gas chromatography with flame ionization detection. The plasma kinetics showed rapid oral absorption of RA and C18:2 trans-10, cis-12 (t1/2a 0.34 ± 0.09 and 0.53 ± 0.01 h) and slow elimination (t1/2ß 25.68 ± 3.29 and 18.12 ± 1.71 h); the maximal isomer plasma concentrations (Cmax) of 8.48 ± 0.98 and 7.67 ± 0.80 µg mL-1, respectively, were estimated at 2.08 ± 0.14 and 2.26 ± 0.11 h. Our results from a preclinical kinetic study in rats help to design future studies in humans for evaluating the CLA isomer dose-response.

Evidences and perspectives in the utilization of CLNA isomers as bioactive compounds in foods.

Conjugated alpha linolenic acid (CLNA) isomers are promising lipids owing to their similarities with conjugated linoleic acid (CLA) but exerting their bioactivity at lower doses; some isomers also belong to omega 3 family. This review aims to summarize the state of the art about the utilization of CLNA as a functional ingredient. Indeed, in vitro and in vivo studies reported that CLNA exerted anticancer, anti-inflammatory, anti-obese, and antioxidant activities. However, CLNA has not been tested in humans. These compounds are naturally present in meat and milk fat from ruminants but the highest concentrations are found in vegetable oils. Their incorporation in foodstuffs is one of the most effective strategies to elaborate CLNA-enriched products together with the microbiological production. Lactobacilli, propionibacteria, and bifidobacteria strains have been assayed to produce CLNA isomers but at the current moment there are not high CLNA concentration products elaborated using these strains. Furthermore, it is known that CLNA isomers are highly prone to oxidation when compared with linoleic acid and CLA, but the possible effects of elaboration and storage on high CLNA productsare unknown.The utilization of CLNA as a functional compound still remains a challenge and requires more research to address all of its technological and bioactivity aspects.

Antiproliferative activity of buttermilk lipid fractions isolated using food grade and non-food grade solvents on human cancer cell lines.

Buttermilk is a dairy by-product with a high content of milk fat globule membranes (MFGMs), whose protein constituents are reported to be antiproliferative. Lipids represent about half of the composition of MFGM. The aim of this study was to isolate buttermilk lipid fractions and evaluate their potential antiproliferative effect. Selective extraction with food grade or non-food grade solvents was performed. Antiproliferative effectiveness of lipid extracts and their neutral and polar fractions was evaluated on nine human cancer cell lines. Fractions obtained using food grade ethanol gave a higher yield than those obtained using non-food grade solvents, and they effectively inhibited cell viability of the cancer cell lines investigated. These fractions, rich in phospho- and sphingolipids, were strongly antiproliferative against human ovary and colon cancer cells. This observation allowed us to hypothesize further analyses aimed at promoting the use of buttermilk polar lipid fractions as functional food additives.