Linoleic Acid Isomers Research Articles

Influences of Maternal Conjugated Linoleic Acid and Essential Fatty Acid Supply During Late Pregnancy and Early Lactation on T and B Cell Subsets in Mesenteric Lymph Nodes and the Small Intestine of Neonatal Calves.

Conjugated linoleic acid (CLA) isomers are known for their health-promoting effects in mammals and metabolic functions in dairy cows and are synthesized in the forestomach depending on essential fatty acid (EFA) intake. The current preliminary study investigated effects of a maternal fatty acid supplementation (MFAS) during late pregnancy and early lactation with coconut oil (CON, control), CLA (Lutalin®), or CLA + EFA (Lutalin® linseed oil; safflower oil) on plasma fatty acid composition and T and B cell subsets in mesenteric lymph nodes (MLN) and the small intestine of 5-day-old calves. MFAS of CLA + EFA increased α-linolenic, eicosapentaenoic, docosapentaenoic, and n-3 fatty acid proportions in calf plasma fat on days 1 and 5 after birth (P < 0.05). On day 5, CLA and CLA + EFA calves showed higher plasma fat trans-10, cis-12 CLA proportions, and CLA calves had higher plasma cis-9, trans-11 CLA proportions compared with CON calves (P < 0.1). MFAS of CLA tended to increase CD4+ T cell subsets in MLN and increased CD21+ B cell subsets in ileal lamina propria compared with CON but decreased CD2+ T cell subsets in jejunal lamina propria (P < 0.05). CLA + EFA decreased CD4+ T cell subsets in MLN compared with CLA (P < 0.05). MFAS of CLA seemed to affect the intestinal adaptive immune system of calves, but additional EFA supplementations reversed CLA effects. Possible direct CLA and EFA effects or whether changes in milk composition affected this immune modulation must be clarified in further studies.

Effect of production system on fatty acid composition in subcutaneous adipose tissue of Ile de France lambs

Effect of production system on fatty acid composition in subcutaneous adipose tissue of Ile de France lambs

Punicic acid production in Brassica napus

Punicic acid (PuA; 18:3Δ9cis,11trans,13cis), a conjugated linolenic acid isomer bearing three conjugated double bonds, is associated with various health benefits and has potential for industrial use. The major nature source of this unusual fatty acid is pomegranate (Punica granatum) seed oil, which contains up to 80% (w/w) of its fatty acids as PuA. Pomegranate seed oil, however, is low yielding with unstable production and thus limits the supply of PuA. Metabolic engineering of established temperate oil crops for PuA production, therefore, has the potential to be a feasible strategy to overcome the limitations associated with sourcing PuA from pomegranate. In this study, the cDNAs encoding a pomegranate fatty acid conjugase and a pomegranate oleate desaturase were co-expressed in canola-type Brassica napus. Transgenic B. napus lines accumulated up to 11% (w/w) of the total fatty acids as PuA in the seed oil, which is the highest level of PuA reported in metabolically engineered oilseed crops so far. Levels of seed oil PuA were stable over two generations and had no negative effects on seed germination. The transgenic B. napus lines with the highest PuA levels contained multiple transgene insertions and the PuA content of B. napus seed oil was correlated with efficiency of oleic acid desaturation and linoleic acid conjugation. In addition, PuA accumulated at lower levels in polar lipids (5.0–6.9%) than triacylglycerol (7.5–10.6%), and more than 60% of triacylglycerol-associated PuA was present at the sn-2 position. This study provides the basis for the commercial production of PuA in transgenic oilseed crops and thus would open new prospects for the application of this unusual fatty acid in health and industry.

In vitro effects of conjugated linoleic acid (CLA) on inflammatory functions of bovine monocytes

The conjugated linoleic acid (CLA) isomers, a group of naturally occurring isomers of the essential fatty acid (FA) linoleic acid, have received special attention in animal and human nutrition. Although they have long been used as dietary integrators in dairy cows, the effects of CLA isomers on bovine immune cells remain mostly undisclosed. The present study aimed to cover this gap and investigate the in vitro effects of CLA on inflammatory functions, including chemotaxis, phagocytosis, killing capability, and extracellular respiratory burst of purified bovine monocytes (CD14+). The apoptosis rate of monocytes was addressed as well. Once assessed, the effects of different concentrations (10, 50, 100, and 500 μM) of the 2 main CLA isomers, namely cis-9,trans-11 and trans-10,cis-12, the experiments were carried out using a concentration of 50 μM of the CLA isomers, both individually and in a mixture (50:50). The immunomodulatory activities of linoleic acid, an essential FA, and stearic acid, a saturated FA, were also investigated. Only the 50:50 CLA mixture was able to reduce monocyte apoptosis and to increase the extracellular respiratory burst during experimental proinflammatory conditions, as assessed by measuring production of reactive oxygen species. Linoleic acid and CLA had no effects on chemotaxis, phagocytosis, or killing capability. Remarkably, treatment of monocytes with stearic acid significantly reduced their chemotactic capability. The present results demonstrated that CLA isomers do have immunomodulatory effects on some functions of bovine monocytes, and that the mixture of the 2 CLA isomers is more effective than the CLA isomers individually.

Microencapsulation of pomegranate (Punica granatum L.) seed oil by complex coacervation: Development of a potential functional ingredient for food application

The objective of this study was to develop a functional ingredient containing punicic acid, a bioactive conjugated linolenic acid isomer, via microencapsulation of pomegranate seed oil (PSO) by complex coacervation. Whey protein and gum Arabic were used as encapsulating agents and spray drying was applied as a hardening step. The effects of total polymer concentration (Cp) (2.2–7.8 g/100 mL) and wall material:oil ratio (WM:Oil) (0.5–5.0) on microparticles physical-chemical characteristics (oil retention, microencapsulation efficiency (ME), punicic acid content and particle size) were evaluated, according to a 22 rotatable central composite design. Microparticles' morphology and surface composition were also assessed. Both Cp and WM:Oil ratio affected oil retention, ME, punicic acid content and particle size. Intermediate values of Cp and WM:Oil ratio were considered the best conditions for PSO encapsulation, resulting in the highest oil retention (near 100 g/100 g; and punicic acid content, near 64 g/100 g fatty acid). High Cp and low WM:Oil ratios promoted microparticles’ agglomeration. PSO microparticles rich in punicic acid were successfully produced by complex coacervation, enabling future use of PSO as a functional ingredient in food products.

Engineering Trienoic Fatty Acids into Cottonseed Oil Improves Low-Temperature Seed Germination, Plant Photosynthesis and Cotton Fiber Quality.

Alpha-linolenic acid (ALA, 18:3Δ9,12,15) and γ-linolenic acid \ (GLA, 18:3Δ6,9,12) are important trienoic fatty acids, which are beneficial for human health in their own right, or as precursors for the biosynthesis of long-chain polyunsaturated fatty acids. ALA and GLA in seed oil are synthesized from linoleic acid (LA, 18:2Δ9,12) by the microsomal ω-3 fatty acid desaturase (FAD3) and Δ6 desaturase (D6D), respectively. Cotton (Gossypium hirsutum L.) seed oil composition was modified by transforming with an FAD3 gene from Brassica napus and a D6D gene from Echium plantagineum, resulting in approximately 30% ALA and 20% GLA, respectively. The total oil content in transgenic seeds remained unaltered relative to parental seeds. Despite the use of a seed-specific promoter for transgene expression, low levels of GLA and increased levels of ALA were found in non-seed cotton tissues. At low temperature, the germinating cottonseeds containing the linolenic acid isomers elongated faster than the untransformed controls. ALA-producing lines also showed higher photosynthetic rates at cooler temperature and better fiber quality compared to both untransformed controls and GLA-producing lines. The oxidative stability of the novel cottonseed oils was assessed, providing guidance for potential food, pharmaceutical and industrial applications of these oils.

Characterisation of Formaggella della Valle di Scalve Cheese Produced from Cows Reared in Valley Floor Stall or in Mountain Pasture: Fatty Acids Profile and Sensory Properties

An important problem in mountain areas is the abandonment of pasture. This trend can be combated by the valorisation of typical dairy products, such as “Formaggella della Valle di Scalve”, a semi-cooked traditional cheese made from whole milk in a mountain area in Italy. The aim of the present research was to compare the fatty acid (FA) profile and the sensory properties of this cheese as manufactured under different conditions: i) from the milk of cows grazing on mountain or valley pasture or fed indoors; ii) from the milk of cows fed hay or fed silage. In the first case, five cheesemaking trials were conducted during two years for each of the following situations: mountain pasture (A); pasture at the bottom of the valley (P) (about 1000m asl); stall (S). In the second case, three cheesemaking trials were conducted for each of the following situations: cows fed silage (I); cows fed hay (F). S cheese was richer in medium-chain FAs, while long-chain FAs were higher in P and A cheeses. On the other hand, long chain fatty acids (LCFA) were more abundant in P and A cheeses than in S. In general, MUFA, PUFA and, consequently, total unsaturated FA (UFA), were significantly higher in the P and A cheeses than S (UFA: 36.55 and 38.34, respectively, vs. 31.13; p < 0.001), while SFA showed higher values in S (68.85 vs. 63.41 and 61.68 in P and A, respectively; p < 0.001). Conjugated linoleic acid isomers (CLA) were more represented in the P and A samples (1.86 in P and 1.52 in A, vs. 0.80 in S; p < 0.001); Omega 3 fatty acids, and in particular α-linolenic acid, were more abundant in P than in S cheese. In winter, the I sample (silage) presented higher percentages of myristic (C14), myristoleic (C14:1) and omega 6 acids, whereas F cheese (hay) contained higher concentrations of CLA. The triangular test of sensory analysis showed that, in general, F cheeses were judged as “sweeter” than I, with aromatic profiles characterized by higher content of 2- butanol and ethyl capronate.

NMR Lipid Profile of Milk from Alpine Goats with Supplemented Hempseed and Linseed Diets.

The supplementation of goat diets with natural products to obtain milk with nutraceutical components is a common practice. In these last years, the influence of supplementation of specifically designed diets has been studied with different analytical tools in order to explore possible beneficial effects in human consumption of animal milk and milk-derived products. In this study, the lipid fraction of milk from Alpine goats undergoing different dietary regimens was studied by 1H-NMR spectroscopy. Alpine goats were fed with linseed or hempseed supplements, and after 14 weeks of treatment, milk was collected and analyzed. Results showed that feeding diets supplemented with seeds positively affected the fatty acid composition with a pronounced increase in unsaturated fatty acids for both diets compared to a control diet. Specifically, linolenic acid content was more than doubled for linseed diet compared with the hempseed and control groups, while linoleic acid greatly increased only upon hempseed supplementation. However, a number of conjugated linoleic acid (CLA) isomers and higher levels of fatty acids with trans configuration were found in supplemented diets, particularly in the linseed diet.

Effect of Breed on Fatty Acid Composition of Meat and Subcutaneous Adipose Tissue of Light Lambs.

Simple SummaryThe recognition of the role of food in the improvement and preservation of health is receiving more and more attention among consumers, especially in developed countries. Fats from red meats are considered quite unhealthy because of their high levels of cholesterol and saturated fatty acids. Healthier lipid profiles of red meats can be achieved by a proper feed composition of animals, but other factors, such as breed, sex, and live weight, are able to affect the nutritional properties of meats. This investigation aimed to evaluate the effect of breed (Bergamasca, Italian Merino, and Sopravissana) on the fatty acid composition of invisible (intramuscular) and visible (subcutaneous) fats of light lambs reared in Central Italy transhumant farms. They recently gained a Protected Geographical Indication label (European Union, Commission Implementing Regulation No. 475/2013), as ”Agnello del Centro Italia”. It is an income opportunity for local farms that passes through the nutritional valorization of lamb meat. The indices of nutritional quality of fats have showed that the meat of Italian Merino and Sopravissana lambs had better nutritional quality than the Bergamasca breed.Lamb meat is the main product of Central Italy transhumant farms, where lambs are traditionally reared with their mothers on pastures and are supplemented with concentrates and/or hay from day 20–30 until slaughter. However, few data are available on the fatty acid (FA) composition of unweaned lambs reared by extensive systems in Central Italy. The study aimed to evaluate the effect of breed (Bergamasca, Italian Merino, and Sopravissana) on the FA composition of intramuscular (longissimus lumborum, LL) and subcutaneous (SC) fats of light lambs. Statistical analysis showed that breed had effect only on some FAs in LL muscle fat (C18:0, C20:0, C14:1, C16:1, C17:1, C18:3 n-3, trans and conjugated linoleic acid isomers) and in SC adipose tissue (C21:0, C16:1, C18:1, C20:4 n-6, C20:5 n-3, C18:1 trans isomers). Gas chromatography data in combination with a chemometric approach could have some potential to discriminate among breeds. Indices of nutritional quality of the lipids suggested that the meat of Italian Merino and Sopravissana lambs might have better nutritional quality than Bergamasca; further studies, involving a greater number of animals, are needed to confirm these early results.

Maternal and Early Postnatal Diet Supplemented with Conjugated Linoleic Acid Isomers Affect Lipid Profile in Hearts of Offspring Rats with Mammary Tumors.

Simple SummaryProper feeding during pregnancy and breastfeeding plays an important role in ensuring the health of offspring in childhood as well as in adulthood. The idea of the “developmental origin of health and disease” (DOHaD) assumes that stimuli acting during fetal life cause long-term developmental and physiological changes in the main organs and influence the risk of many diseases. Our research, connected with DOHaD, made an attempt to evaluate the impact of the diet modification of mothers through the addition of conjugated linoleic acid isomers (CLA) on the lipid profile, fatty acid profile and the oxidative stress in the hearts of offspring with breast cancer. Earlier studies utilizing CLA in DOHaD concerned their impact on reducing the incidence of cancer. Considering reports on the co-occurrence of cardiovascular diseases (CVD) in oncological patients as a result of tumor development and also after chemotherapy and radiotherapy, further research is needed to assess the potential protective effect of CLA isomers in CVD. For this purpose, the content of selected CVD biomarkers was determined using modern analytical techniques. Our research has tried to explain the physiological role of CLA and its mechanism of action in the context of maintaining good health and in the prevention of non-communicable diseases.Linking the early life environment with later health status is known as “developmental programming”. This study aimed to assess whether the introduction of conjugated linoleic acids (CLAs) into the maternal diet affects the content fatty acids (FAs), conjugated FAs (CFAs), cholesterol, oxysterols, malondialdehyde (MDA) and tocopherols in the hearts of their female offspring treated with 7,12-dimethylbenz[a]anthracene and if offspring supplementation enhanced the effect of maternal supplementation. FA, cholesterol and oxysterol contents were determined by gas chromatography-mass spectrometry, while contents of CFAs and MDA were determined by high-performance liquid chromatography (HPLC) with photodiode detection. The supplementation of mothers with CLAs significantly decreased the amount of atherogenic saturated FAs and enhanced the level of eicosapentaenoic FA in the hearts of offspring. Continuous progeny supplementation decreased the content of arachidonic acid in hearts. Supplementation of the maternal diet with CLAs and its continuation during the postnatal period increased the ratio of hypo to hypercholesterolemic FAs. Significantly fewer oxysterols were detected in the hearts of progeny of dams fed with CLAs as compared to the offspring of mothers receiving safflower oil. Both fetal and postnatal CLA intake significantly reduced 7β-hydroxycholesterol accumulation. It can be concluded that CLA supplementation during the fetal and postnatal period may be an effective method of maintaining the cardiac health status of newborns.

C9, t11, c15-CLNA and t9, t11, c15-CLNA from Lactobacillus plantarum ZS2058 Ameliorate Dextran Sodium Sulfate-Induced Colitis in Mice.

To investigate the specific functions of conjugated fatty acids (CFAs) produced by the probiotic bacterium, α-linolenic acid was isomerized by Lactobacillus plantarum ZS2058, and two different conjugated linolenic acid (CLNA) isomers were successfully isolated: c9, t11, c15-CLNA (CLNA1) and t9, t11, c15-CLNA (CLNA2). The effects and mechanism of CLNA crude extract and individual isomers on colitis were explored. CLNA significantly inhibited weight loss, the disease activity index, and colon shortening. Additionally, CLNA alleviated histological damage, protected colonic mucus layer integrity, and significantly upregulated the concentration of tight junction proteins (ZO-1, occludin, E-cadherin 1, and claudin-3). CLNA significantly attenuated the level of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) while upregulating the expression of the colonic anti-inflammatory cytokine IL-10 and nuclear receptor peroxisome-activated receptor-γ. Moreover, CLNA increased the activity of oxidative stress-related enzymes (SOD, GSH, and CAT), and the myeloperoxidase activity was significantly decreased by CLNA. Meanwhile, the concentrations of CLNA in the liver and conjugated linoleic acid in the colonic content were significantly increased because of the treatment of CLNA. Furthermore, CLNA could rebalance the intestinal microbial composition of colitis mice, including increasing the α-diversity. CLNA1 and CLNA2 increased the abundance of Ruminococcus and Prevotella, respectively.

In silico characterization of linoleic acid biotransformation to rumenic acid in food derived Lactobacillus plantarum YW11.

Lactobacillus plantarum YW11 capability to convert linoleic acid into conjugated linoleic acid and other metabolites was studied in a dose-dependent manner by supplementing LA at different concentrations. L. plantarum YW11 displayed a uniform distinctive growth curve of CLA and other metabolites at concentrations of LA ranging from 1% (w/v) to 10% (w/v), with slightly increased growth at higher LA concentrations. The biotransformation capability of L. plantarum YW11 evaluated by GC-MS revealed a total of one CLA isomer, i.e. 9-cis,11-trans-octadecadienoic acid, also known as the rumenic acid (RA), one linoleic acid isomer (linoelaidic acid), and LA metabolites: (E)-9-octadecenoic acid ethyl ester, trans, trans-9,12-octadecadienoic acid, propyl ester and stearic acid. All the metabolites of linoleic acid were produced from 1 to 10% LA supplemented MRS media, while surprisingly the only conjugated linoleic acid compound was produced at 10% LA. To assess the presence of putative enzymes, responsible for conversion of LA into CLA, in silico characterization was carried out. The in silico characterization revealed presence of four enzymes (10-linoleic acid hydratase, linoleate isomerase, acetoacetate decarboxylase and dehydrogenase) that may be involved in the production of CLA (rumenic acid) and LA isomers. The biotransformation ability of L. plantarum YW11 to convert LA into RA has great prospects for biotechnological and industrial implications that could be exploited in the future scale-up experiments.

Effect of dietary inclusion of chia seed (Salvia hispanica L.) on goat cheese fatty acid profile and conjugated linoleic acid isomers

The effects of two dietary inclusion levels of chia seed (CHigh and CLow) on the FA profile and CLA isomers in cheese was evaluated. Dry matter and fat contents in cheese were higher (P < 0.05) in CHigh compared with control and CLow and the content of C18:0, C18:1n9c, total monounsaturated fatty acids, total polyunsaturated fatty acids increased (P < 0.05); total CLA content in CHigh cheese increased (P < 0.05) from 0.32% to 0.66%. Compared with control, saturated fatty acids (SFA) decreased (P < 0.05) by 3.4% with CHigh, due to a reduction of C14:0 and C16:0 in the cheese. The following CLA isomers were increased (P < 0.05) by CHigh: cis-9, trans-11; trans-7, cis-9; trans-11, cis-13 and trans-12, trans-14. Addition of chia seed at 5.5% DM in dairy goat diets can be used to increase the amount of bioactive FA, such as cis-9, trans-11 C18:2 in cheese.

Conjugated Linoleic Acid Supplemented Diet Influences Serum Markers in Orchidectomized Sprague‐Dawley Rats

AbstractConjugated isomers of linoleic acid have beneficial effects on human health, with demonstrated anticarcinogenic, antiatherogenic, antioxidant, and anti‐inflammatory properties. Previous studies have shown that the loss of sex hormones induced by orchidectomy affects vascular function and serum lipids. The objective of this work is to evaluate the effect of conjugated linoleic acid (CLA) on serum lipids, cardiac, renal, and hepatic markers in orchidectomized Sprague‐Dawley rats. Male sex hormone deprivation is induced by orchidectomy to 24‐week‐old rats. The rats are fed a diet containing 1.8% w/w CLA, or a control diet for 8 weeks. At the end of the treatment, serum markers are measured using commercially available kits. The concentrations found in the orchidectomized‐CLA (ORX‐CLA) group of total cholesterol, low‐density lipoproteins (LDL), as well as the atherogenic index, concentrations of creatine kinase, lactate dehydrogenase, C‐reactive protein, glucose, urea, uric acid, creatinine, albumin, calcium, total protein, and bilirubin are significantly lower compared to the orchidectomized‐control (ORX‐C) group. The concentrations of high‐density lipoproteins (HDL), calcium, total protein, albumin, total bilirubin, and indirect bilirubin are significantly higher in the ORX‐CLA group than in the ORX‐C group. The CLA‐supplemented diet exerts a beneficial effect on different biochemical parameters negatively affected by orchidectomy, which may result in vascular protection.Practical Applications: The relationship between testosterone deficiency and the alteration of serum lipids is demonstrated; however, it is demonstrated in this study that the markers of renal damage, cardiac damage, and oxidative stress are also negatively affected by the lack of this hormone. This information has enriched the understanding about the relationship between testosterone deficiency and the development of different diseases such as metabolic syndrome, type 2 diabetes, kidney failure, osteoporosis, cardiovascular diseases, and cancer. On the other hand, CLA has been studied mainly as a nutraceutical and sports supplement; the information in this study will help to expand the knowledge about the benefits of these isomers of linoleic acid, providing guidelines for its use as a protection against negative effects triggered by orchidectomy.

The influence of conjugated linoleic acid on the expression of peroxisome proliferator-activated receptor-\u03b3 and selected apoptotic genes in non-small cell lung cancer

In recent years, peroxisome proliferator-activated receptor-γ (PPARγ) has been intensively studied. Because its activation is often associated with changes in the expression level of various apoptotic genes, many studies have emphasized the role of PPARγ as an important anticancer agent. However, in different types of cancer, different genes are influenced by PPARγ action. Previous studies showed that conjugated linoleic acid (CLA) was able to induce apoptosis, upregulate PPARG gene expression and activate PPARγ protein in certain human cancer cell lines. Moreover, some PPARγ agonists inhibited the growth of human lung cancer cells through the induction of apoptosis. Nevertheless, the impact of CLA on PPARγ mRNA and protein levels in non-small cell lung cancer (NSCLC) cell lines has not been investigated thus far. Therefore, in our study, we analysed the influence of the c9,t11 linoleic acid isomer on the expression of PPARG and other genes involved in the apoptotic response (BCL-2, BAX, and CDKN1A) in two NSCLC cell lines of different histological origin (A549 and Calu-1) and in normal human bronchial epithelial Beas-2B cells. Cells were treated with several doses of c9,t11 CLA, followed by RNA and protein isolation, cDNA synthesis, real-time quantitative PCR (RT-qPCR) and Western blot analysis. We showed that the investigated CLA isomer was able to enhance the expression of PPARγ in the examined cell lines and alter the mRNA and protein levels of genes involved in apoptosis. Fluorescent staining and MMT assay revealed the antiproliferative potential of CLA as well as its ability to activate pathways that lead to cell death.

Potential Health Benefits of Conjugated Linoleic Acid: An Important Functional Dairy Ingredient

Conjugated linoleic acid (CLA) refers to a class of positional and geometrical isomers of linoleic acid (cis-9, cis-12 octadecadienoic acid) having conjugate double bond system. CLA are synthesized in rumen of the ruminants by biohydrogenation of dietary fatty acids; and thus, can be obtained from dairy products as well as from the meat of sheep, lamb and other ruminants. Among the several isomers, c9, t11-CLA isomer is the most biologically active form and accounts approximately 80% of total isomers. A number of clinical and epidemiological studies have demonstrated the role of CLA as anti-atherogenic, anti-inflammatory, anti-oxidative, anti-carcinogenic, etc. Several researchers have suggested the positive association of CLA in weight management, hypercholesterolemia, immunomodulatory functions, and improved bone metabolism.

The effect of storage on the yogurt fatty acid profile

The presented study analysed whether refrigerated storage time affects the fatty acid profile, the content of conjugated linoleic acid (CLA) and trans isomers of C18:1 and C18:2 acids in yogurts made from goat, sheep and cow milk. On the 21st day of storage, significant decreases (P&amp;lt;0.05) in monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) were observed in in yogurts made from cow milk. In yogurts made from sheep and goat milk, the content of these acids fluctuated during storage. The CLA isomer in fresh yogurts ranged from 3.58 mg g-1 fat in yogurts made from sheep milk to 4.47 mg g-1 fat in yogurts made of cow milk. During storage the content of CLA significantly decreased in cow milk yogurts and significantly increased in goat milk yogurts (P&amp;lt;0.05), while it remained more or less unchanged throughout the entire storage period in sheep milk yogurts.

Basal anti-inflammatory responses in cultured endothelial cells exposed to two conjugated linoleic acids

AbstractConjugated linoleic acid (CLA) isomers have been shown to possess anti-atherosclerotic properties, which may be related to the downregulation of inflammatory pathways. Whether low concentrations of CLAs are able to affect basal, unstimulated endothelial cell (EC) responses is not clear. The aim of this study was to evaluate the effects of two CLAs (cis-9, trans-11 and trans-10, cis-12) on basal inflammatory responses by ECs.EA.hy926 cells (HUVEC lineage) were cultured under standard conditions and exposed to CLAs (1 and 10 μM) for 48 hours. MTT assay was performed to determine cell viability; incorporation of FA was confirmed by gas chromatography; inflammatory mediators were assessed by multiplex immunoassay; the relative expression of genes encoding transcription factors and inflammatory cytokines was assessed through real-time PCR and static adhesion assay was used to evaluate monocyte attachment to the EC monolayer.CLAs were incorporated into ECs in a dose-dependent manner. Pre-treatment with CLA9,11 (1 uM) significantly reduced unstimulated, basal concentrations of MCP-1 (p &lt; 0.05), and CLA10,12 at 10 uM had the same effect (p &lt; 0.05). Both CLAs at 10 uM increased the relative expression of NFκβ (p &lt; 0.01 and p &lt; 0.05, respectively), while decreasing the relative expression of PPARα (p &lt; 0.0001), COX-2 (p &lt; 0.0001) and IL-6 (p &lt; 0.0001). In contrast, no effect was observed in the adhesion assay for either CLA.These results suggest that both CLAs at a low concentration have a neutral or modest anti-inflammatory effect in basal conditions, which may influence endothelial function and risk of vascular disease. Interestingly, at these low CLA concentrations some pro-inflammatory genes are upregulated while others are down regulated. This suggests complex effects of CLAs on inflammatory pathways.

Conjugated linoleic acid as a potential bioactive molecule to modulates gamete and embryo cryotolerance

Abstract Conjugated linoleic acid (CLA) is a mixture of positional isomers of linoleic acid found in meat and dairy products from ruminants. It is a trans fat widely used by athletes as a food supplement, due to a supposed effect of maximizing the use of body fat reserves. The interest in diet and culture media supplementation with CLA is an emerging area, demanding studies in order to elucidate its benefits in the reproductive parameters, as well as in cryopreservation. Therefore, the aim of this review was to discuss the effects of CLA on the oocytes, sperm and embryos cryotolerance. Some studies have already demonstrated its use in cryopreservation of germline. Among those, it was observed that CLA supplementation during oocyte in vitro maturation can increase their viability post-freezing and developmental capacity. Regarding the use of CLA on sperm, there are few studies and their results are still inconclusive. Finally, studies about CLA supplementation on embryo culture media have shown promising results, indicating that this bioactive molecule is able to modulate lipid uptake on blastomeres. Altogether, these findings demonstrate the potential use of CLA as a bioactive molecule to improve germline and embryo cryotolerance and open new perspectives on human and animal reproduction field.

Effect of delipidant agents during in vitro culture on the development, lipid content, gene expression and cryotolerance of bovine embryos.

In vitro produced embryos are still sensitive to the freezing process which can be explained, in part, by the high-lipid accumulation that characterizes these embryos. Therefore, we aimed to evaluate the effect of delipidating agents, L-carnitine and the trans-10 cis-12 conjugated linoleic acid (CLA) isomer, on blastocyst development, lipid content, gene expression and cryotolerance when added to embryo culture media. Embryos were cultured in four different media: T1: control (n=616), synthetic oviduct fluid (SOF) media with 5% foetal bovine serum (FBS); T2: L-carnitine (n=648), SOF medium with 5% FBS and 0.6mg/ml of L-carnitine; T3: CLA (n=627), SOF medium with 5% FBS and 100μM trans-10 cis-12 CLA; and T4: L-carnitine+CLA: (n=597), SOF medium with 5% FBS plus 0.6mg/ml L-carnitine and 100μM trans-10 cis-12 CLA. Supplementation of culture medium with either or both delipidating agents reduced (p<.05) blastocyst rate on D7 (T1=49±3.5; T2=39±3.0; T3=42±3.9 and T4=39±3.9), but did not affected gene expression (p>.05). Although embryos cultured in the presence of L-carnitine contained fewer (p<.05) lipid droplets than the control embryos, they showed a lower re-expansion rate 24hr post-thaw than those (p<.05). In conclusion, although L-carnitine reduced the amount of lipids in cultured embryos, the use of L-carnitine and CLA during in vitro culture was not able to improve the embryo production and the response to cryopreservation.