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The growing interest in fermented dairy products is due to their health-promoting properties. The use of milk kefir grains as a starter culture made it possible to obtain a product with a better nutritional and biological profile depending on the type of milk. Cow, buffalo, camel, donkey, goat, and sheep milk kefirs were prepared, and the changes in sugar, protein, and phenol content, fatty acid composition, including conjugated linoleic acids (CLAs), as well as antioxidant activity, determined by ABTS and FRAP assays, were evaluated and compared. The protein content of cow, buffalo, donkey, and sheep milk increased after 24 h of fermentation. The fatty acid profile showed a better concentration of saturated and unsaturated lipids in all fermented milks, except buffalo milk. The highest content of beneficial fatty acids, such as oleic, linoleic, and C18:2 conjugated linoleic acid, was found in the cow and sheep samples. All samples showed a better antioxidant capacity, goat milk having the highest value, with no correlation to the total phenolic content, which was highest in the buffalo sample (260.40 ± 5.50 μg GAE/mL). These findings suggested that microorganisms living symbiotically in kefir grains utilize nutrients from different types of milk with varying efficiency. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of beef production and the beef evaluation system in Chile. It emphasizes the importance of low-technology pastoral systems in the majority of beef production in Chile and highlights the health benefits of Chilean beef, which is rich in conjugated linoleic acid, omega-3, and phytochemicals. The classification system for cattle and beef in Chile focuses on carcass quality rather than beef quality. The article discusses the factors contributing to the decline in beef production in Chile, such as climate change, land use opportunities, public policies, regulations, and the unrestricted entry of beef from other countries. It also examines the productive cycle of beef production and the categories used for cattle classification in Chile. The text raises concerns about the lack of economic incentives for higher beef quality and the confusion among consumers. It concludes by discussing the need for modifications to the law, particularly regarding imported beef, and the asymmetry between beef and other meats in terms of labeling and trade requirements. The article also highlights the effects of different feeding systems on the quality of beef produced in Chile, with grass-fed systems showing lower omega-6 to omega-3 ratios and higher levels of beneficial fatty acids compared to concentrate-fed systems. However, it notes the absence of a national policy to promote and educate consumers about the quality of beef produced in Chile. [Extracted from the article]

Conjugated linoleic acid (CLA) is a geometrical isomer of linoleic acid, which has anti-inflammatory, anti-diabetic, anti-cancer, and anti-obesity properties. However, the studies reported inconstant results about the CLA-related effects on lipid profiles. As a result, meta-analysis and systematic review were performed to survey the CLA supplementation-related effect on lipid profile including high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol (TC), and triglycerides (TG). To identify the relevant research, a systematic comprehensive search was initiated on the medical databases such as Scopus and PubMed/Medline until December 2022. The overall effect size was estimated by weighted mean difference (WMD) and 95% confidence interval (CI) in a random effect meta-analysis. In the final quantitative analysis, the meta-analysis considered 35 randomized controlled trials (RCTs) with 1,476 participants (707 controls and 769 cases). The pooled results demonstrated that CLA supplementation, compared with olive oil, significantly increased serum TG levels (WMD: 0.05 mmol/L; 95% CI: 0.01 to 0.1; p = 0.04; I2 = 0.0%, p = 0.91). With regard to TC level, CLA supplementation compared with placebo significantly reduced TC concentrations (WMD: −0.08 mmol/L; 95% CI: −0.14 to −0.02; p < 0.001; I2 = 82.4%). Moreover, the non-linear dose–response analysis indicated a decreasing trend of TC serum level from the 15th week of CLA supplementation compared with olive oil (Pnon-linearity = 0.01). The present meta-analysis and systematic review of 35 RCTs showed that the CLA intervention was able to raise the level of TG in comparison to olive oil; however, it can decrease TC level compared with placebo and olive oil.

The aim of the present study was to investigate the influence of parity on the proportion of fatty acids with potential health significance in camel milk fat. Milk samples were collected from four multiparous and four primiparous camels in intensive husbandry at mid-lactation stage. Fatty acid methyl esters were analysed by gas chromatography in conjunction with a flame ionisation detector. Parity had a significant effect on fat and total solids content (p<0.05); mutiparous camels produced milk with lower fat and total solids content. In contrast, protein and ash content were not affected by parity (p>0.05). Primipara camels produced milk richer (p<0.05) in odd and branched chain fatty acids, monounsaturated fatty acids, C17:0, C15:0, omega-3 fatty acids, oleic acid, vaccenic acid and α-linolenic acid, while poorer (p<0.05) for total short-chain fatty acids, total medium-chain fatty acids, total saturated fatty acids, C6:0, C10:0, C14:0, c9-C16:0, C16:0 and iso-C16:0. In addition, the desaturation index for C16, which is an indicator of Δ9-desaturase activity, and the atherogenicity index were lower in primiparous camels (p<0.05). Parity had no effect on conjugated linoleic acid content (p>0.05). Overall, the milk fat of primiparous camels appears to have a relatively high nutritional value, as it contained higher levels of beneficial fatty acids and lower levels of saturated fatty acids. [ABSTRACT FROM AUTHOR]

This experiment was conducted to study the effects of dietary conjugated linoleic acids (CLAs) on the growth performance, fat metabolism, carcase composition and muscle quality of fattening rabbits. A total of 160 Minxinan black rabbits aged 75 days with body weights of 1658.9 ± 188.8 g were randomly divided into 4 groups. They were fed a basic diet supplemented with 0 (control), 0.5%, 1.0%, or 1.5% CLA for 50 days. Dietary CLA reduced the feed intake and serum triglyceride and cholesterol levels. In addition, the crude protein content in rabbit meat was increased, along with the cholesterol and the ether extract levels in the 1.5% depression group. Moreover, the fatty acid composition in rabbit meat was changed, and the content of polyunsaturated fatty acids/monounsaturated fatty acids (PUFAs/MUFAs) increased with the increasing levels of CLA addition. These findings indicate that CLA greatly improved the nutritional value of rabbit meat. From an economic point of view, CLA would normally be included at a concentration of 0.5% in the formulation of feeds for fattening rabbits.HIGHLIGHTS Minxinan black rabbits were fed conjugated linoleic acid (CLA)- supplemented diets for 50 d. CLA decreased the feed intake of experimental rabbits. CLA has significant effects on fat deposition and serum triglyceride and cholesterol levels. CLA greatly improved the nutritional value of rabbit meat. The recommended CLA level is 0.5% for meat rabbits．

Seasonal variation in fatty acids and minerals concentrations was investigated through the analysis of Pecorino Romano cheese samples collected in January, April, and June. A fraction of samples contained missing values in their fatty acid profiles. Probabilistic principal component analysis, coupled with Linear Discriminant Analysis, was employed to classify cheese samples on a production season basis while accounting for missing data and quantifying the missing fatty acid concentrations for the samples in which they were absent. The levels of rumenic acid, vaccenic acid, and omega-3 compounds were positively correlated with the spring season, while the length of the saturated fatty acids increased throughout the production seasons. Concerning the classification performances, the optimal number of principal components (i.e., 5) achieved an accuracy in cross-validation equal to 98%. Then, when the model was tasked with imputing the lacking fatty acid concentration values, the optimal number of principal components resulted in an R2 value in cross-validation of 99.53%. [ABSTRACT FROM AUTHOR]

This experiment was conducted to study the effects of dietary conjugated linoleic acids (CLAs) on the growth performance, fat metabolism, carcase composition and muscle quality of fattening rabbits. A total of 160 Minxinan black rabbits aged 75 days with body weights of 1658.9 ± 188.8 g were randomly divided into 4 groups. They were fed a basic diet supplemented with 0 (control), 0.5%, 1.0%, or 1.5% CLA for 50 days. Dietary CLA reduced the feed intake and serum triglyceride and cholesterol levels. In addition, the crude protein content in rabbit meat was increased, along with the cholesterol and the ether extract levels in the 1.5% depression group. Moreover, the fatty acid composition in rabbit meat was changed, and the content of polyunsaturated fatty acids/monounsaturated fatty acids (PUFAs/MUFAs) increased with the increasing levels of CLA addition. These findings indicate that CLA greatly improved the nutritional value of rabbit meat. From an economic point of view, CLA would normally be included at a concentration of 0.5% in the formulation of feeds for fattening rabbits. Minxinan black rabbits were fed conjugated linoleic acid (CLA)- supplemented diets for 50 d. CLA decreased the feed intake of experimental rabbits. CLA has significant effects on fat deposition and serum triglyceride and cholesterol levels. CLA greatly improved the nutritional value of rabbit meat. The recommended CLA level is 0.5% for meat rabbits． [ABSTRACT FROM AUTHOR]

Seasonal variation in fatty acids and minerals concentrations was investigated through the analysis of Pecorino Romano cheese samples collected in January, April, and June. A fraction of samples contained missing values in their fatty acid profiles. Probabilistic principal component analysis, coupled with Linear Discriminant Analysis, was employed to classify cheese samples on a production season basis while accounting for missing data and quantifying the missing fatty acid concentrations for the samples in which they were absent. The levels of rumenic acid, vaccenic acid, and omega-3 compounds were positively correlated with the spring season, while the length of the saturated fatty acids increased throughout the production seasons. Concerning the classification performances, the optimal number of principal components (i.e., 5) achieved an accuracy in cross-validation equal to 98%. Then, when the model was tasked with imputing the lacking fatty acid concentration values, the optimal number of principal components resulted in an R2 value in cross-validation of 99.53%.

Fatty acid composition in milk has a vital importance in the early lactation period when lambs are milking. In this study, the change in milk fatty acid composition of Akkaraman ewe and Hair goats fed under the same conditions in the first 30 days of lactation was investigated. 10 Akkaraman ewe and 10 Hair goats were used in 2-5 parities. Ewe and goats were born in February. The animals were kept to the same feeding indoor, while experiment was going on. In addition to 1 kg of barley per animal, wheat straw was given ad libitum. Individual milk samples were taken from each animal on 0th, 1st, 3rd, 7th, 15th and 30th of lactation days. While C16:1, C18:3n3 were found more in goat milk (p<0.05), C20:5n3 (EPA) was found mostly in ewe milk (p<0.01). The mean CLAC9t11 was 0.378±0.1 g/100 in ewe milk and 0.426±0.1 g/100 in goat milk throughout the 30-day lactation. Contrary to the general literature information, the highest CLA ratio in milk was found in goat milk and most lipid health indexes were determined in favor of goats. Omega 6/3 ratio was determined as 7.90±2.5 g/100 g in fatty acids in Akkaraman ewe milk and 10.35±4.7 g/100 g in fatty acids in Hair goat milk (p<0.05). It is an important issue which should be emphasized that the ratios of SFA, MUFA, PUFA, MUFA/SFA, PUFA/SFA and UFA/SFA only in goat milk change in the first 30 days of lactation. [ABSTRACT FROM AUTHOR]

In this study, the hydroxy fatty acid dehydrogenase CLA-DH from Lactobacillus plantarum p-8 and its four mutant variants were expressed in Escherichia coli Rosetta (DE3). UV spectrophotometry was employed to verify the catalytic power of the purified CLA-DH to convert ricinoleic acid into 12-oxo-cis-9-octadecenoic acid in the presence of oxidized nicotinamide adenine dinucleotide (NAD+). The optimum reaction temperature for CLA-DH was 45°C, with a maintained stability between 20°C and 40°C. The optimal pH for CLA-DH catalytic activity was 6.0–7.0, with a maintained stability at a pH range of 6.0–8.0. In addition, Fe3+ promoted enzyme activity, whereas Cu2+, Zn2+, and Fe2+ inhibited enzyme activity (P  < 0.05). The Km, Vmax, Kcat, and Kcat/Km of CLA-DH were determined as 2.19 ± 0.34 μM, 2.06 ± 0.28 μM min−1, 2.00 ± 0.27 min−1, and 0.92 ± 0.02 min−1μM−1, respectively. Site-directed mutagenesis and molecular dynamics simulations demonstrated that both Tyr156 and Ser143 residues play significant roles in the catalysis of CLA-DH, and its solubility is affected by Lys160 and Asp63. Moreover, Gas chromatography determined that recombinant CLA-DH could be successfully applied to Conjugated linoleic acids production. [ABSTRACT FROM AUTHOR]

In the dairy cow, late gestation and early lactation are characterized by a complexity of metabolic processes required for the homeorhetic adaptation to the needs of fetal growth and milk production. Skeletal muscle plays an important role in this adaptation. The objective of this study was to characterize the metabolome in skeletal muscle (semitendinosus muscle) and in serum of dairy cows in the context of the physiological changes occurring in early lactation and to test the effects of dietary supplementation (from d 1 in milk onwards) with conjugated linoleic acids (sCLA; 100 g/d; supplying 7.6 g of cis -9, trans -11 CLA and 7.6 g of trans -10, cis -12 CLA per cow/d; n = 11) compared with control fat-supplemented cows (CTR; n = 10). The metabolome was characterized in skeletal muscle samples collected on d 21 and 70 after calving in conjunction with their serum counterpart using a targeted metabolomics approach (AbsoluteIDQ p180 kit; Biocrates Life Sciences AG, Innsbruck, Austria). Thereby 188 metabolites from 6 different compound classes (acylcarnitines, amino acids, biogenic amines, glycerophospholipids, sphingolipids, and hexoses) were quantified in both sample types. In both groups, dry matter intake increased after calving. It was lower in sCLA than in CTR on d 21, which resulted in reduced calculated net energy and metabolizable protein balances. On d 21, the concentrations of dopamine, Ala, and hexoses in the skeletal muscle were higher in sCLA than in CTR. On d 21, the changed metabolites in serum were mainly long-chain (>C24) diacyl phosphatidylcholine PC (PC-aa) and acyl-alkyl phosphatidylcholine (PC-ae), along with lysophosphatidylcholine acyl (lysoPC-a) C26:1 that were all lower in sCLA than in CTR. Supplementation with CLA affected the muscle concentrations of 22 metabolites on d 70 including 10 long-chain (>C22) sphingomyelin (SM), hydroxysphingomyelin [SM(OH)], PC-aa, and PC-ae along with 9 long-chain (>C16) lysoPC-a and 3 metabolites related to amino acids (spermine, citrulline, and Asp). On d 70, the concentrations of lysoPC-a C18:2 and C26:0 in serum were higher in the sCLA cows than in the CTR cows. Regardless of treatment, the concentrations of Ile, Leu, Phe, Lys, His, Met, Trp, and hydroxybutyrylcarnitine (C4-OH) decreased, whereas those of ornithine, Gln, and trans -4-hydroxyproline (t4-OH-Pro) increased from d 21 to 70 in muscle. The significantly changed metabolites in serum with time of lactation were 28 long-chain (>C30) PC-ae and PC-aa, 7 long-chain (>C16) SM and SM(OH), along with lysoPC-a C20:3 that were all increased. In conclusion, in addition to other significantly changed metabolites, CLA supplementation mainly led to changes in muscle and serum concentrations of glycerophospholipids and sphingolipids that might reflect the phospholipid compositional changes in muscle. The metabolome changes observed in sCLA on d 21 seem to be, at least in part, due to the lower DMI in these cows. The changes in the muscle concentrations of AA from d 21 to 70, which coincided with the steady energy and MP balances, might reflect a shift of protein synthesis/degradation balance toward synthesis. [ABSTRACT FROM AUTHOR]

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.

Obesity is considered a serious global health issue. Patients have been predisposed to comorbidities such as dyslipidemia, cardiovascular diseases, diabetes, cancers, and osteoarthritis. Certain fats in the diet have been linked with an increase in obesity, such as saturated and trans-fats. Meanwhile, some dietary fats such as conjugated linoleic acids (CLAs) and medium-chain triglycerides (MCTs) could potentially reduce energy intake. Various mechanisms for reducing weight by CLAs and MCTs, such as increased lipolysis, improved intestinal microbiota, up-regulating peroxisome proliferator-activated receptors (PPARs), increased the expression of uncoupling protein of respiratory chain-1 (UCP-1), and affected satiety hormones are included. These bioactive compounds, CLAs and MCTs, should be used in moderate concentrations to prevent harmful effects such as insulin resistance for CLAs and hypercholesterolemia for MCTs. However, several studies have proposed CLAs or MCTs as adjuvants to the protocol used to minimize bodyweight. Our objective is to summarize the different causes of obesity and to discuss the effects of CLAs or MCTs on body weight and fat deposition in obese animals or humans. [ABSTRACT FROM AUTHOR]

The present study aimed to review the literature on publications that evaluated the association between the intake of conjugated linoleic acid (CLA) and body composition in humans. This is a systematic review of the Pubmed, Lilacs and Scielo databases, with no restrictions on the year of publication and language of the studies. Medical Subject Headings (MeSH) was used to locate the terms. This review followed the rules of the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA). Five hundred and eighty-three studies were found, of which 28 were in the inclusion criteria and were included in the review. Thirteen studies found no type of association and 15 found some association between CLA and body composition in humans. There appears to be no difference between moderate and high doses in the results. The main result of this study is that CLA appears to work modestly on fat loss in overweight or obese people. However, further studies are needed to prove the long-term effectiveness and safety of CLA. [ABSTRACT FROM AUTHOR]

Background Aging is associated with skeletal muscle anabolic resistance (i.e. reduced muscle protein synthesis during anabolic conditions such as hyperaminoacidemia). The results from studies conducted in cell culture systems and animals suggest that both vitamin D and conjugated linoleic acids (CLAs) stimulate muscle protein synthesis. Objectives To conduct a randomized, double-blind, placebo-controlled clinical trial to determine the independent and combined effects of dietary vitamin D and CLA supplementation on myofibrillar protein synthesis rates in sedentary older adults. Methods Thirty-two sedentary, older adults were randomized to receive either: 1) 2000 IU vitamin D-3 (Vit D) per day; 2) 4000 mg CLA per day; 3) both Vit D (2000 IU/d) and CLA (4000 mg/d); or 4) placebo for 8 wk. Myofibrillar protein synthesis rates were evaluated by using intravenous [ring-2H5]phenylalanine infusion in conjunction with muscle biopsies during basal, postabsorptive conditions and during combined amino acid and insulin infusion before and after the supplementation period. Results Before the intervention, basal myofibrillar protein synthesis rates were not different among groups (Placebo: 0.033 ± 0.003; Vit D: 0.034 ± 0.002; CLA: 0.029 ± 0.005; Vit D + CLA: 0.038 ± 0.005 %·h-1), and hyperinsulinemia–hyperaminoacidemia increased myofibrillar protein synthesis rates by ∼35%. Compared with placebo, neither Vit D nor CLA nor combined Vit D + CLA supplementation affected the basal myofibrillar protein synthesis rates (placebo: 0.040 ± 0.004%/h; Vit D: 0.044 ± 0.006%/h; CLA: 0.039 ± 0.006%/h; Vit D + CLA: 0.040 ± 0.007%/h) or the hyperinsulinemia–hyperaminoacidemia–induced increase in myofibrillar protein synthesis (percentage increase from basal before and after the interventions: placebo, 30 ± 11 and 36 ± 11; Vit D, 38 ± 8 and 34 ± 10; CLA, 50 ± 14 and 51 ± 16; Vit D + CLA, 29 ± 15 and 35 ± 8). Conclusions Vitamin D and/or CLA supplementation, at the doses provided in our study, does not have muscle anabolic effects in sedentary older adults. The study was registered at clinicaltrials.gov (NCT03115775). [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the concentration of fatty acids (FA) especially conjugated linoleic and trans fatty acids in milk from Jersey cows fed green alfalfa (GA) or alfalfa hay (AH). Forty Jersey cows that had from two to five calvings, 60 to 90 lactation days and were not pregnant were used in a confined production system. In one treatment (GA n=20) cows were fed chopped fresh green alfalfa and commercial concentrate. In the other one (AH n=20), they were fed alfalfa hay and the same commercial concentrate. A milk sample (10 mL) was collected from each cow. Total lipids, methyl-esterified fatty acids (FA), and conjugated linoleic acids (CLA) were determined by chromatography. The amount of saturated, monounsaturated and polyunsaturated FA were similar between treatments (P>0.05). The content of FA omega-3 and omega-6, as well as the proportion of omega-6:omega-3 were not affected by the type of forage (P>0.05). However, the concentrations of vaccenic acid-trans (P<0.01), rumenic acid (P<0.01), total FA trans (P<0.001), and total CLA (P<0.01) were higher in cows fed GA. We conclude that consumption of green chopped alfalfa in Jersey cows increased production of 18:1 n-7 trans-11 trans-vaccenic acid and CLA in milk. [ABSTRACT FROM AUTHOR]

The study investigated the effect of low-crude protein (CP), essential aminoacids (EAAs) and conjugated linoleic acid (CLA) on broiler growth performance. From 1 to 6 days of age, 196 male broiler chicks fed the same basal diet containing 22.5% of crude protein. From 7-28 days the chicks were assigned to 7 treatments (4 replicates, 7 birds/replicate). The control group fed a 21.5% CP diet, supplemented with dl-methionine (Met) and l-lysine (Lys). The low-CP diet (19% CP) was supplemented with Met + Lys (2EAAs group) or with Met, Lys, l-arginine, l-tryptophan and l-threonine (5EAAs group); 2EAAs and 5EAAs groups were also supplemented with 0, 2 or 4% CLA. The body weight gain (BWG) was the biggest (p

Obesity is globally acknowledged as a major public health concern and future threat which is associated with its co-morbidities in particular diabetes, hypertension, cardiovascular diseases, osteoarthritis, stroke and inflammatory diseases. It was suggested that a high-fat diet promotes the development of obesity and that there is a direct relationship between the amount of dietary fat and the degree of obesity. Fats and oils, particularly higher molecular weight and saturated fats, lead to a positive fat balance, and consequent adipose mass accumulation; therefore, for good health, the type of fats/oils people eat is far more important that the amount, and there is some evidence that the same may be true for weight control. Advancements in food processing sector and modernisation of the societies lead to changes in lifestyle which attracts the consumers to modify their diet accordingly. Therefore, there is great scope of designer foods that could help in prevention or management of obesity. Lipid components, including medium chain triglycerides (MCTs), diacylglycerides (DAGs), conjugated linoleic acids (CLAs) and omega-3 fatty acids (ω-3 FAs) are extensively studied for their anti-obesity effects. The same may give a way in the area of research on weight management by incorporating them in the regular diet or in food formulation as functional components because of their beneficial effects on energy intake and expenditure. [ABSTRACT FROM AUTHOR]

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP (P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM (P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA (P < 0.001) and vaccenic acid (P < 0.01), but lower proportions of branched-chain FA (P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and α-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile.

The present study investigated the effects of dietary conjugated linoleic acid (CLA) on the cellular immune response of piglets after cyclosporin A (CsA) treatment. The experimental study had a 2×2 factorial design, and the main factors consisted of diets (0% or 2% CLA) and immunosuppression treatments (CsA or saline injection). CsA injection significantly increased feed : gain (F : G) of piglets (P

Trans- 10, cis- 12-conjugated linoleic acid (CLA) is a potent bioactive fatty acids (FA) that causes milk fat depression in lactating animals. FA are transferred to milk directly through chylomicrons and indirectly by recycling through other tissues. The objective of this study was to characterise the kinetics of trans -10, cis -12 CLA transfer to plasma and milk after a single bolus infusion. Five multiparous mid-lactation cows received a single abomasal bolus infusion of an enriched CLA mixture providing 15 g of trans- 10, cis- 12 CLA and 15 g of cis- 9, trans- 11 CLA over a 30-min period. Plasma concentration of trans- 10, cis- 12 and cis- 9, trans- 11 CLA peaked 2 h post-bolus, reaching 0·29 and 0·38 % of total plasma FA, respectively, and returned to pre-bolus values at 72 h post-infusion. Milk trans- 10, cis- 12 CLA yield and concentration peaked 14 h post-bolus (0·25 g/h) and was not detectable in milk after 86 h. Total apparent transfer of trans- 10, cis- 12 CLA to milk was 41 %, with 73 % transferred to milk through the direct pool (chylomicrons) and the remaining 27 % transferred through the indirect pool (tissue recycling). Compartmental modelling revealed the existence of a transient unavailable pool of trans- 10, cis- 12 CLA in extravascular tissues represented primarily by the mammary gland, which slowly exchanges with an available pool for secretion in milk fat and transfer to milk. In conclusion, trans- 10, cis- 12 CLA is predominantly transferred to milk through the direct pathway; however, how this CLA isomer is processed within the mammary gland requires further investigation. [ABSTRACT FROM AUTHOR]

Pigment epithelium-derived factor (PEDF) is evolving as metabolic regulatory protein. Albeit mostly considered in only pathological conditions related to excess energy intake resulting in obesity and insulin resistance, PEDF is likely to be involved in other physiological processes such as the homeorhetic adaptation of metabolism to lactation. We aimed to characterize the expression of PEDF and its association to the concomitant mobilization of body reserves during lactation in nonobese subjects. This mobilization is particularly distinct in dairy cows, and we therefore assessed the mRNA expression of PEDF and its putative receptors in different tissues in 2 trials with dairy cows fed with or without conjugated linoleic acids (CLAs). Conjugated linoleic acids depress milk fat synthesis and may thus reduce the drain of energy via milk. In pluriparous cows, the serum PEDF concentrations and the mRNA abundance in subcutaneous adipose tissue (scAT), as well as the hepatic and scAT mRNA abundance of the putative receptors, adipose triglyceride lipase, and laminin receptor 1, changed over time of sampling (day −21 until day 252 relative to calving). Conjugated linoleic acid treatment was associated with reduced PEDF concentrations in serum and lower PEDF mRNA abundance in scAT on day 21 postpartum. Comparing different tissues from primiparous cows, PEDF mRNA was highest in the liver, followed by scAT, visceral adipose tissue (AT), and mammary gland, and lowest in the muscle. Significant changes in PEDF expression with time of sampling were limited to AT in primiparous and pluriparous cows. Our data support a regulatory role for PEDF. The similarities between the time course of the serum concentrations of PEDF and its mRNA abundance in scAT may point to a regulatory role for AT rather than the liver for PEDF in dairy cows. [ABSTRACT FROM AUTHOR]

Background Studies have showed the protective effects of conjugated linoleic acid (CLA) on intestinal epithelium, modulating host immune and inflammatory responses on intestinal diseases. Objective To evaluate the preventive effects of CLA on the intestinal mucositis induced by 5-FU in a murine model. Methods Sixty-four BALB/c mice were randomly divided into four groups: Control (CTL), fed a standard chow diet; CLAs, fed a diet supplemented with CLA; Mucositis (5-FU), fed a standard chow diet and underwent mucositis induction and CLAs 5-FU, fed a diet supplemented with CLA and underwent mucositis induction. Mucositis was induced by intraperitoneal injection of 300 mg/kg 5-FU. After 72 h, the animals were euthanized and intestinal permeability, bacterial translocation, inflammatory mediators, and intestinal histology were evaluated. Results Mice in the CLAs 5-FU group showed reduced weight loss compared to those in the 5-FU group (p < 0.005). Furthermore, the results also showed that the treatment with CLA reduced intestinal permeability, bacterial translocation, and biomarkers of inflammatory response besides minor damage to ZO-1 and occludin with maintenance of the integrity of the intestinal epithelium and a favorable balance between the inflammatory and regulatory cytokines. Conclusion This study suggests that CLA reduced the adverse effects from 5-FU administration on the intestinal mucosa. [ABSTRACT FROM AUTHOR]

Conjugated linoleic acid (CLA)‐rich lysophosphatidylcholine (LPC) with many proven beneficial effects is successfully synthesized by an immobilized mutant lipase (MAS1‐H108A)‐catalyzed esterification of glycerophosphorylcholine (GPC) and CLA‐rich FAs. Under the optimized conditions (temperature of 55 °C, substrate molar ratio of CLA‐rich FAs to GPC of 40:1, and enzyme loading of 300 U g−1), LPC content as high as 89.10 mol.% is achieved, which is exceptionally higher than any ever‐reported value. By monitoring the esterification process, it is found that sn1‐LPC is easy to synthesize and is the predominant product, while sn2‐LPC and phosphatidylcholine (PC) are difficult to synthesize and are with lower content in the final product. The formed sn2‐LPC during esterification may mainly attribute to the acyl migration of sn1‐LPC and the ratio of sn1‐LPC to sn2‐LPC finally plateaus at approximately 7. Besides, our results also demonstrate that sn2‐LPC is the main template for the synthesis of PC. Finally, a complete reaction scheme for the synthesis of LPC by immobilized MAS1‐H108A‐catalyzed esterification of GPC and fatty acids is mapped out. Overall, the highest LPC content can be obtained by immobilized MAS1‐H108A‐catalyzed esterification and there is the first study for systematical studying the reaction process of CLA‐rich LPC synthesis. Practical Applications: Previous studies have demonstrated that Novozym 435 is the most suitable catalyst for the synthesis of CLA‐rich LPC. However, the LPC content obtained by Novozym 435 is only 70 mol.% and the reaction process for the synthesis of CLA‐rich LPC has not been studied systematically, which restricts the commercial production of CLA‐rich LPC in some extent. Therefore, further exploration of alternative enzyme resources for highly efficient synthesis of CLA‐rich LPC and trying to clarify the reaction process of CLA‐rich LPC synthesis are of significant importance for the future commercially industrial production of CLA‐rich LPC. A complete reaction scheme for the synthesis of LPC using GPC and FAs as substrates by immobilized MAS1‐H108A‐catalyzed esterification. CLA‐rich FAs are used as model FAs in this study. Reaction parameters, such as temperature, CLA‐rich FAs/GPC ratio, and enzyme loading are selected to study their effects on the esterification. Concurrently, the reaction process is monitored. LPC content as high as 89.10 mol.% is obtained, which is the highest reported value thus far for the synthesis of CLA‐rich LPC. Finally, the reaction scheme for the synthesis of LPC by immobilized MAS1‐H108A‐catalyzed esterification is mapped out. [ABSTRACT FROM AUTHOR]

Rumen microorganisms are the origin of many bioactive fatty acids (FA) found in ruminant-derived food products. Differences in plant leaf anatomy and chemical composition between cool- and warm-season pastures may alter rumen microorganisms, potentially enhancing the quantity/profile of bioactive FA available for incorporation into milk. The objective of this study was to identify rumen bacteria and protozoa and their cellular FA when cows grazed a warm-season annual, pearl millet (PM), in comparison to a diverse cool-season pasture (CSP). Individual rumen digesta samples were obtained from five Holstein cows in a repeated measures design with 28-day periods. The treatment sequence was PM, CSP, then PM. Microbial DNA was extracted from rumen digesta and sequence reads were produced with Illumina MiSeq. Fatty acids (FA) were identified in rumen bacteria and protozoa using gas-liquid chromatography/mass spectroscopy. Microbial communities shifted in response to grazing regime. Bacteria of the phylum Bacteroidetes were more abundant during PM than CSP (P < 0.05), while protozoa of the genus Eudiplodinium were more abundant during CSP than PM (P < 0.05). Microbial cellular FA profiles differed between treatments. Bacteria and protozoa from cows grazing CSP contained more n-3 FA (P < 0.001) and vaccenic acid (P < 0.01), but lower proportions of branched-chain FA (P < 0.05). Microbial FA correlated with microbial taxa and levels of vaccenic acid, rumenic acid, and a-linolenic acid in milk. In conclusion, grazing regime can potentially be used to alter microbial communities shifting the FA profile of microbial cells, and subsequently, alter the milk FA profile. [ABSTRACT FROM AUTHOR]

Fatty acid (FA) profile plays an important role on human health and on sensory quality of dairy products. There is few information about breed influence on milk FA profile of local goat breeds. This study aimed to characterize and compare the milk FA profile of 5 local endangered goat breeds (Garganica, Girgentana, Jonica, Maltese, and Mediterranean Red) and a cosmopolitan breed (Saanen) reared in the same farm during a complete lactation. A total of 252 milk samples were collected monthly from 42 goats (7 goats per breed) and analyzed for gross composition and FA profile. Individual FA was determined using gas-chromatography. Data were analyzed using a mixed model with repeated measures with breed and week of lactation as fixed effects. Results showed that the FA profile was significantly affected by week of lactation and only few FA by breed effect (p < 0.05). Overall, the main differences were found between Saanen and local breeds. This study contributed to the characterization of goat milk FA profile, and it may be of interest for the valorization of milk from local goat breeds which seem to have a healthier profile than milk of the cosmopolitan breed.

Background: Little information about the effects of conjugated linoleic acids (CLAs) on inflammation and immune function in humans is available. This study investigated the effects of CLAs, with and without Vitamin E on immunity and inflammatory parameters in adults with active rheumatoid arthritis (RA). Methods: In a double-blind clinical trial, 78 patients were randomly divided into four groups, each group receiving one of the following daily supplement for 3 months; group C: 2.5 g CLAs, group E: 400 mg Vitamin E, group CE: CLAs plus Vitamin E, group P: Placebo. Cytokines, matrix metalloproteinase 3 (MMP-3) and citrullinated antibody (CCP-A) were measured by ELISA method and Vitamin E by high-performance liquid chromatography. Results: Consider statistical methods there were no significant differences between groups in cytokines interleukin-2 (IL-2), IL-4, tumor necrosis factor-α (TNF-α), IL-1β, IL-2/IL-4, CCP-A white blood cells and neutrophils, lymphocyte, monocytes, and eosinophils numbers. TNF-α decreased in all groups, but its reduction was significant in group CE. IL-1β increased in groups P (P = 0.004) and E (P = 0.041) but the difference between group P and CE was significant. IL-4 decreased in groups C, CE and E (P = 0.03, P = 0.03, P = 0.07 respectively). IL2 did not change significantly within groups. CCP-A increased in groups P (P = 0.035) and E (P = 0.05), while it decreased in groups CE (P = 0.034). CCP-A and MMP-3 decrease were significant between groups P and CE. MMP-3 reduction was significant in group CE. Conclusions: Co-supplementation CLAs and Vitamin E may be effective in the level of inflammatory markers in RA patients.

Aim To undertake a systematic review and meta-analysis of prospective studies to determine the effect of conjugated linoleic acids ( CLAs) supplementation on serum C-reactive protein ( CRP). Method Pub Med- Medline, Web of Science, Cochrane Database, and Google Scholar databases were searched (up until May 2016) to identify prospective studies evaluating the impact of CLAs supplementation on serum CRP. Random-effects models meta-analysis was used for quantitative data synthesis. Sensitivity analysis was conducted using the leave-one-out method. Heterogeneity was quantitatively assessed using the I2 index. Systematic review registration: CRD42016038945. Results From a total of 85 entries identified via searches, 14 studies were included in the final selection. The meta-analysis indicated a significant increase in serum CRP concentrations following supplementation with CLAs (weighted mean difference [ WMD] 0.63 mg/dL, 95% confidence interval [95% CI] 0.13-1.13, N=21 arms, heterogeneity P=.026; I2=52.3%). These findings were robust in sensitivity analyses. Random-effects meta-regression revealed that changes in serum CRP levels were independent of the dosage of CLAs supplementation (slope: −0.02; 95% CI: −0.10, 0.12; P=.889) or duration of follow-up (slope: 0.271; 95% CI: −0.05, 0.59; P=.098). Conclusions This meta-analysis suggests that CLA supplementation is associated with an increase in plasma CRP concentrations and a reduction in serum adiponectin concentrations, which indicates that CLA supplements have a proinflammatory effect. Randomized control trials with larger sample size and a longer follow-up period may be required for future investigations to provide an unequivocal answer. [ABSTRACT FROM AUTHOR]

The study investigated the effect of low-crude protein (CP), essential aminoacids (EAAs) and conjugated linoleic acid (CLA) on broiler growth performance. From 1 to 6 days of age, 196 male broiler chicks fed the same basal diet containing 22.5% of crude protein. From 7-28 days the chicks were assigned to 7 treatments (4 replicates, 7 birds/replicate). The control group fed a 21.5% CP diet, supplemented with DL-methionine (Met) and L-lysine (Lys). The low-CP diet (19% CP) was supplemented with Met+Lys (2EAAs group) or with Met, Lys, L-arginine, L-tryptophan and L-threonine (5EAAs group); 2EAAs and 5EAAs groups were also supplemented with 0, 2 or 4% CLA. The body weight gain (BWG) was the biggest (p<.01) in the control group; 2EAAs and 2EAAs 4% CLA groups had lower BWG than the three groups fed 5EAAs diets. Diet 5EAAs +2% CLA induced lower (p<.01) feed conversion ratio (FCR) than 5EAAs +4% CLA and also showed the lowest (p<.01) protein intake. Reducing CP in broiler diet increased (p<.01) the digestibility of CP. The total protein content of plasma was greater (p<.01) in 2EAAs +4%CLA and 5EAAs +4%CLA than in the control. Decreasing the protein content of the diet from 21.5 to 19.0% penalised the growth performance of broilers from 7 to 28 days of age and the administration of CLA at 2 or 4% was not able to support growth. However, addition of 5EAAs without or with 2 or 4% of CLA resulted in recovery of FCR and PCR. [ABSTRACT FROM AUTHOR]

Conjugated linoleic acids (CLAs) play a major role in adipocyte differentiation and lipid metabolism in animals. MicroRNAs (miRNAs) appear to be involved in many biological processes in adipose tissue. However, the specific influence on miRNAs by CLA supplementation in porcine adipose tissue remains unclear. Thus, we continuously added 1.5% CLA to the pig diet from the embryo stage to the finishing period and conducted a high-throughput sequencing approach to analyse the changes in adipose tissue miRNAs. We identified 283 known porcine miRNAs, and 14 miRNAs were differentially expressed in response to CLA treatment. A Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the targets of the 14 differentially expressed miRNAs were involved in the Wnt signalling pathway. The CLA treatment downregulated the gene expression of PPAR, C/EBPα, FAS, and FATP1 in both subcutaneous and abdominal fat tissues; the analysis showed that ssc-miR-21 expression was significantly correlated with PPAR expression (p < 0.05), and speculated that ssc-miR-21 might influence adipogenesis through PPAR. In conclusion, our study analysed the miRNA profiles in porcine adipose tissues by CLA treatment, and demonstrated that miRNAs are important regulators of fat lipogenesis. This study provides valuable information for the molecular regulatory mechanism of CLA on adipose tissue. [ABSTRACT FROM AUTHOR]

Conjugated linoleic acids (CLAs) have been found to have beneficial effects on human health when used as dietary supplements. However, their availability is limited because pure, chemistry-based production is expensive, and biology-based fermentation methods can only create small quantities. In an effort to enhance microbial production of CLAs, four genetically modified strains of the oleaginous yeast Yarrowia lipolytica were generated. These mutants presented various genetic modifications, including the elimination of β-oxidation ( pox1- 6∆), the inability to store lipids as triglycerides ( dga1∆ dga2∆ are1∆ lro1∆ ), and the overexpression of the Y. lipolytica ∆12-desaturase gene (Yl FAD2) under the control of the constitutive p TEF promoter. All strains received two copies of the p TEF- oPAI or p POX- oPAI expression cassettes; PAI encodes linoleic acid isomerase in Propionibacterium acnes. The strains were cultured in neosynthesis or bioconversion medium in flasks or a bioreactor. The strain combining the three modifications mentioned above showed the best results: when it was grown in neosynthesis medium in a flask, CLAs represented 6.5% of total fatty acids and in bioconversion medium in a bioreactor, and CLA content reached 302 mg/L. In a previous study, a CLA degradation rate of 117 mg/L/h was observed in bioconversion medium. Here, by eliminating β-oxidation, we achieved a much lower rate of 1.8 mg/L/h. [ABSTRACT FROM AUTHOR]

A qualitative and quantitative analysis of trans fatty acids (TFAs), conjugated linoleic acids (CLAs) and linoleic acid/α-linolenic acid (ω6/ω3) in eleven different brands of fresh and heated corn oil was investigated. Corn oil was subjected to thermal treatment at 180, 210 and 230 °C for 4, 8 and 12 h. The kinds of fatty acids were almost the same in all eleven brands of corn oil, but there were differences in the quantities of TFAs, CLAs and ω6/ω3 among the brands. The formation of TFAs in different brands of corn oil increased slowly at 180 °C and rapidly at 230 °C with the maximum increase of 28 and 374%, respectively. The formation of CLAs also increased during the heating with the amount of 0.00-0.32 g/100 g in fresh corn oil and 0.71-1.12 g/100 g in corn oil heated at 230 °C for 12 h. The value of ω6/ω3 was high in corn oil and increased with heating temperature and time. The largest rise of ω6/ω3 can reach upwards of 239:1. The results showed that temperature control was essential for maintaining the quality and nutritional value of corn oil. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate ruminal biohydrogenation (BH) and apparent transfer of long-chain (FA) from duodenum into milk in dairy goats fed Ca salts of palm oil (CaS, 45 g/d) or lipid-encapsulated conjugated linoleic acids (LE-CLA, 45 g/d providing 4.5 g trans-10, cis-12 C18:2/d and 4.5 g cis-9, trans-11 C18:2/d). Twelve lactating multiparous dairy Saanen or Alpine goats (65±3 days in milk) were randomly allocated to two experimental treatments (CaS vs LE-CLA) for a 3 wks experiment. The goats were fitted with a ruminal cannula and a T-type duodenal cannula for the measurement of duodenal flow by supplying 2.4 g of Cr 2 O 3 /d through the rumen cannula during 3 wks: the first one was for reaching steady-state concentration of this marker in the digestive tract, the second wk was for measuring the daily flow of faecal chrome and nutrient faecal digestibility, and the third wk was for the duodenal sampling. LE-CLA did not affect intake, duodenal flow and apparent ruminal digestibility of DM, OM, NDF and starch. Compared to CaS, LE-CLA tended to decrease total digestibility of DM and NDF whereas total digestibility of starch was not affect by dietary treatments. The duodenal flow of FA was higher than FA intake in goats fed CaS or LE-CLA. LE-CLA increased the duodenal flows of C18:2 trans-10, cis-12, and C18:2 cis-9, trans-11, leading to a calculated 16% protection from BH for both FA. The LE-CLA treatment tended to decrease the duodenal flows of C18:2 cis-9, trans-12 and C18:2 trans-9, cis-12. The ruminal biohydrogenation of C18:1 cis-9, C18:2 cis-9, cis-12, and C18:3 cis-9, cis-12, cis-15 was not affected by the LE-CLA treatment. Average apparent transfer between the duodenum and milk fat was 22%, 44%, 36% and 22% for C18:2 trans-10, cis-12, C18:2 cis-9, trans-11+ C18:1 trans-11, C18:2 cis-9, cis-12 and C18:3 cis-9, cis-12, cis-15, respectively. Apparent transfer efficiency of long-chain FA was not affected by LE-CLA treatment. [ABSTRACT FROM AUTHOR]

The demand for dairy products from grass-fed cows is driven, in part, by their more desirable fatty acid (FA) profile, containing more n-3 FA and conjugated linoleic acids (CLA) than conventionally produced dairy products. This study investigated the effects of pearl millet (PM) vs . cool-season pasture (CSP) on animal performance and milk FA in a grazing system. Eight Holstein dairy cows were used in a repeated measures design with four-week periods. Forage type had no effect on animal performance (estimated dry matter intake, milk production, fat, or protein). The contents of CLA and n-3 FA in a serving of whole milk (3.25% fat) increased when cows grazed CSP compared to PM. A serving of whole milk from cows grazing PM had a higher content of saturated FA and branched-chain FA. In conclusion, the contents of various bioactive FA were higher in milk fat of cows grazing a CSP compared to PM. [ABSTRACT FROM AUTHOR]

On the basis of the isomer-specific effects of trans fatty acids (FA) on human health, and the detrimental effect of t10,c12-conjugated linoleic acid (CLA) on cows’ milk fat production, there is a need to identify factors that affect the shift from trans-11 to trans-10 pathway during ruminal biohydrogenation of FA. This experiment was conducted in vitro and aimed at separating the effects of the diet of the donor cows from those of the fermentative substrate, which is necessary to prevent this shift. A total of four dry Holstein dairy cows were used in a 4 × 4 Latin square design. They received 12 kg of dry matter per day of four diets based on maize silage during four successive periods: the control diet (22% starch,

From the simultaneous accumulation of hydrogenation intermediates and the disappearance of Isotricha prostoma after algae supplementation, we suggested a role of this ciliate and/or its associated bacteria in rumen biohydrogenation of unsaturated fatty acids. The experiments described here evaluated the role of I. prostoma and/or its associated endogenous and exogenous bacteria in rumen biohydrogenation of C18:2n-6 and its main intermediates CLA c9t11 and C18:1t11. Fractions of I. prostoma and associated bacteria, obtained by sedimentation of rumen fluid sampled from a monofaunated sheep, were used untreated, treated with antibiotics or sonicated to discriminate between the activity of I. prostoma and its associated bacteria, the protozoan or the bacteria, respectively. Incubations were performed in triplicate during 6 h with unesterified C18:2n-6, CLA c9t11 or C18:1t11 (400 μg/ml) and 0.1 g glucose/cellobiose (1/1, w/w). I. prostoma did not hydrogenate C18:2n-6 or its intermediates whereas bacteria associated with I. prostoma converted a limited amount of C18:2n-6 and CLA c9t11 to trans monoenes. C18:1t11 was not hydrogenated by either I. prostoma or its associated bacteria but was isomerized to C18:1c9. A phylogenetic analysis of clones originating from Butyrivibrio-specific PCR product was performed. This indicated that 71% of the clones from the endogenous and exogenous community clustered in close relationship with Lachnospira pectinoschiza. Additionally, the biohydrogenation activity of solid-associated bacteria (SAB) and liquid-associated bacteria (LAB) was examined and compared with the activity of the non-fractioned I. prostoma monofaunated rumen fluid (LAB + SAB). Both SAB and LAB were involved in rumen biohydrogenation of C18:2n-6. SAB fractions performed the full hydrogenation reaction to C18:0 while C18:1 fatty acids, predominantly C18:1t10 and C18:1t11, accumulated in the LAB fractions. SAB and LAB sequence analyses were mainly related to the genera Butyrivibrio and Pseudobutyrivibrio with 12% of the SAB clones closely related to the C18:0 producing B. proteoclasticus branch. In conclusion, this work suggests that I. prostoma and its associated bacteria play no role in C18:2n-6 biohydrogenation, while LAB convert C18:2n-6 to a wide range of C18:1 fatty acids and SAB produce C18:0, the end product of rumen lipid metabolism.

The present review provides an outline of the current knowledge of trans fatty acids (TFA) including their structure and formation, occurrence in foods, especially in meat and meat products, and some estimation and evaluation of daily intake. Special emphasis is put on conjugated linoleic acids (CLA), related to unique beneficial physiological properties, such as on cancer inhibition via the immune system.

Naheed Aryaeian1, Farhad Shahram2, Mahmoud Djalali1, Mohammad R Eshragian3, Abolghasem Djazayeri1, Abdolfatah Sarrafnejad4, Nasim Naderi2, Maryam Chamari1, Fariha Fatehi1, Mahnaz Zarei11Department of Nutrition and Biochemistry, School of Public Health and Institute of Public Health Research, Tehran University of Medical Sciences, Iran; 2Rheumatology Research Center, Shariati Hospital, Tehran University of Medical Sciences, Iran; 3Department of Epidemiology and Biostatistics, School of Public Health and Institute of Public Health Research, Tehran University of Medical Sciences, Iran; 4Department of Immunology, School of Public Health and Institute of Public Health Research, Tehran University of Medical Sciences, IranAbstract: The aim of this study was to assess the impact of conjugated linoleic acids (CLAs), vitamin E, and combination of these nutrients on serum lipid profiles and blood pressure (BP) in patients with active rheumatoid arthritis (RA). In a randomized, double-blind, placebo-controlled trial, 87 patients with active RA were divided into four groups receiving one of the following daily supplements for three months: Group C: CLAs 2.5 g equivalent to 2 g mixture of cis 9-trans 11 and trans 10-cis12 CLAs in a rate of 50/50; Group E: vitamin E: 400 mg; Group CE: CLAs and vitamin E at above doses: Group P: placebo. After supplementation, SBP levels decreased significantly in the group C in comparison with groups E and P and mean arterial pressure reduced signifi cantly in groups C and CE. There weren’t significant differences in the levels of prostaglandin E2 (PGE2), triglycerides, cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), LDL/HDL, cholesterol/HDL, fasting blood sugar, C-reactive protein (CRP), arylestrase activity, platelet count and body mass index between groups. CRP dropped nonsignificantly in groups P, C, E and CE (19%, 24%, 55%, and 39%, respectively). Erythrocytes sedimentation rate levels decreased in groups C, E and CE (P ≤ 0.05, P ≤ 0.05, P ≤ 0.001, respectively). It is concluded that supplementation of CLAs decreased BP and vitamin E decreased CRP. Therefore cosupplementation of CLAs and vitamin E might be profitable for heart disease prevention in RA patients.Keywords: rheumatoid arthritis, lipid profiles, blood pressure, conjugated linoleic acids, vitamin E

The definition and evaluation of trans fatty acids (TFA) with regard to foodstuffs and health hazard are not consistent. Based on the current situation, the term should be restricted only to TFA with isolated double bonds in trans-configuration. Conjugated linoleic acids (CLA) should be separately assessed. Ideally, the origin of the consumed fat should be declared, i.e., ruminant TFA (R-TFA) and industrial TFA (non-ruminant; I-TFA). In ruminant fat, more than 50% of R-TFA consists of vaccenic acid (C18:1 t11). In addition, natural CLA, i.e., c9,t11 CLA is also present. Both are elevated in products from organic farming. In contrast to elaidic acid (t9) and t10, which occur mainly in partially hydrogenated industrial fat, t11 is partially metabolized into c9,t11 CLA via Δ9-desaturation. This is the major metabolic criterion used to differentiate between t11 and other trans C18:1. t11 indicates health beneficial effects in several studies. Moreover, CLA in milk fat is associated with the prevention of allergy and asthma. An analysis of the few studies relating to R-TFA alone makes clear that no convincing adverse physiological effect can be attributed to R-TFA. Only extremely high R-TFA intakes cause negative change in blood lipids. In conclusion, in most European countries, the intake of R-TFA is assessed as being low to moderate. Restriction of R-TFA would unjustifiably represent a disadvantage for organic farming of milk. [ABSTRACT FROM PUBLISHER]

The present study investigated the effects of dietary conjugated linoleic acid (CLA) on the cellular immune response of piglets after cyclosporin A (CsA) treatment. The experimental study had a 2×2 factorial design, and the main factors consisted of diets (0% or 2% CLA) and immunosuppression treatments (CsA or saline injection). CsA injection significantly increased feed : gain (F : G) of piglets (P<0.05); however, dietary CLA significantly decreased F : G of piglets (P<0.05). Dietary CLA partly ameliorated the deterioration of the feed conversion rate caused by CsA treatment (P<0.01). CsA treatment significantly decreased the percentages of CD4+ and CD8+ T lymphocytes in the thymus (P<0.01). Dietary CLA increased the percentages of CD4+ CD8+ double-positive and CD8+ single-positive T lymphocytes in the thymus (P<0.05), and had the trend to inhibit the decrease of CD4+ T lymphocytes in the thymus after CsA injection (P=0.07). CsA treatment significantly depleted the peripheral blood CD3+, CD4+ and CD8+ T lymphocytes (P<0.01). Dietary CLA significantly increased the number of peripheral blood CD8+ T lymphocytes and interleukin-2 (IL-2) production (P<0.05), and inhibited the decreases of peripheral blood CD3+, CD4+ and CD8+ T lymphocytes counts (P<0.01) as well as IL-2 production (P<0.05) after CsA treatment. Dietary CLA partly rescued the decrease of lymphocyte proliferation after CsA injection (P<0.05). In summary, dietary CLA effectively ameliorated CsA-induced cellular immunosuppression in piglets. [ABSTRACT FROM PUBLISHER]

Three sample preparation procedures for producing a solution of fatty acid methyl esters (FAME) from the liver, subcutaneous fat and muscle of 9 bulls were compared. Fat was extracted from fresh samples using solvents under ambient (Folch) or high temperature and pressure (ASE) conditions. As an alternative to Folch, a one-step procedure carried out on freeze-dried samples (Jenkins) was used to produce FAME solutions. All methods involved mild acid-base transmethylation and in each case 9 samples of each tissue type were analyzed in duplicate, resulting in the quantification of 77 FAs. Equal amounts of total FAs were extracted with the different methods. The effect of the method on the FA profile was low in fat, intermediate in liver, and high in muscle. Compared with Folch, ASE resulted in higher saturated and monounsaturated FAs and fewer polyunsaturated FAs (PUFAs), and a lower relative incidence of conjugated linoleic acids (CLA) in muscle (>25%) and liver (17%). Jenkins had a smaller influence than Folch on PUFAs, and caused only a weak reduction in CLA (<3.4%). ASE tended to cause greater oxidation of PUFAs and unacceptable alterations to CLAs compared with Folch. The Jenkins procedure is a valid alternative to Folch when freeze-drying of samples is appropriate. [ABSTRACT FROM AUTHOR]

This study was conducted to estimate the effect of dietary conjugated linoleic acids (CLA) on intramuscular and subcutaneous fat deposition in Yellow Breed × Simmental cattle. The experiment was conducted for 60 days. The results showed that the average backfat thickness, (testicles + kidney + pelvic) fat percentage and subcutaneous fat percentage in dietary CLA were significantly lower than in the control group, while intramuscular the fat percentage was significantly higher. Compared to the control group, the Longissimus muscle enzyme activities of lipoprotein lipase (LPL), fatty acid synthase (FAS) and acetyl-coenzyme A carboxylase (ACC) in dietary CLA and the subcutaneous fat enzyme activities of LPL, hormone-sensitive lipase (HSL) and carnitine palmitoyltransferase-1 (CPT-1) were significantly increased. Similarly, compared to the control group, the Longissimus muscle sterol regulatory element binding protein 1 (SREBP-1), FAS, stearoyl-coenzyme A desaturase (SCD), ACC, peroxisome proliferator-activated receptor γ (PPARγ), heart fatty-acid binding protein (H-FABP) and LPL gene expression in dietary CLA were significant increased, as were the subcutaneous fat of PPARγ, H-FABP, LPL, CPT-1 and HSL in dietary CLA. These results indicated that dietary CLA increases IMF depositionmainly by the up-regulation of lipogenic gene expression, while decreasing subcutaneous fat deposition mainly by the up-regulation of lipolytic gene expression. [ABSTRACT FROM AUTHOR]

The prevalence of type 2 diabetes, a pathology mainly induced by nutrition is increasing. In vivo studies on rat have demonstrated the interest of n-3 long chains polyunsaturated fatty acids (n-3 LC PUFA) and conjugated linoleic acids (CLA) in the diet to improve insulin sensibility. This study investigates the effect of a diet with products (linseed enriched livestock diet products and linseed bread) naturally enriched in n-3 PUFA and CLA 9-cis, 11-trans on glycemic parameters of type 2 diabetics. 44 type 2 diabetics were randomised in three parallel groups and followed a particular diet during 100 days. The three diets: diet A (n = 13), enriched in n-3 PUFA via bread, eggs and pastas, diet B (n = 13), enriched in n-3 PUFA and richer in conjugated linoleic acids (CLA) via bread, eggs, pastas, beef meat and dairy products and diet T (n = 18), standard, were otherwise similar in energy (1970 kcal per day) and type of food. The serum value of the ALA is significantly higher for group A and B and the CLA serum value is significantly higher for the group B only at the end of the study. At the end of the study, fasting insulinemia is lower in group B compared with group A (p = 0,06) and T (p < 0,05) while glycemia does not differ between groups. Insulin resistance is also lower in group B compared with groups A and T, but the differences do not reach significance (p = 0,08 and p = 0,1 respectively). These results suggest the potential implication of CLA 9-cis, 11-trans in a diet rich in ALA in the improvement of insulin sensitivity.

We measured the effects of feeding conjugated linoleic acids (CLA) on the various components of energy expenditure in two species known to react differently to CLA treatments, the hamster and the mouse. We measured in particular resting energy expenditure, and the metabolic responses to feeding and treadmill exercise. Our results confirmed the poor responsivenes of hamsters and the high sensibility of mice. In agreement with the lack of effects of CLAs on body weight and body composition in hamsters, we did not find any significant effects on the various components of energy expenditure. Mice responded to CLA feeding by a complete inhibition in the development of the white adipose tissue, but we observed only marginal effects of the components of energy expenditure, and it was difficult to separate the metabolic alterations that resulted from the energy deficit and those that could be specifically attributed to CLAs feeding. However, the possibility that a high spontaneous activity together with the progressive development of a form of insulin resistance participate in the lipoatrophy observed in mice.

The involvement of protein kinase C (PKC) and nuclear factor-κB (NF-κB) signaling pathway in immunoregulatory actions of conjugated linoleic acid (CLA) in chicken T lymphocyte was investigated. T lymphocytes in peripheral blood were isolated and cultured. The PKC and NF–κB inhibitors, staurosporine (SP) and pyrrolidine dithiocarbamate (PDTC), were used. SP inhibited the production of PKC, and PDTC partly blocked the NF–κB mRNA relative expression. Data suggested compared with c9, t11-CLA and t10, c12-CLA groups, the attenuated effects were showed in SP or PDTC treatment with the application of CLA, which suggested PKC and NF–κB mediated in the immunity of CLA. Furthermore, SP and PDTC inhibited the IL-2 secretion and T lymphocyte proliferation. SP or PDTC induced reduction of IL-2 secretion and T-lymphocytes proliferation were greatly or partially attenuated by CLA isomers. In conclusion, CLA was a potent immunomodulator for T lymphocytes through targeting the PKC–NF–κB pathway. [ABSTRACT FROM AUTHOR]

The effects of microfiltration and storage time on the contents of cholesterols, conjugated linoleic acids, particle size distributions, and fatty acid profiles in pasteurized milk were investigated over 7 days. After microfiltration, the cholesterol (except for day 7) andtrans-10,cis-12 conjugated linoleic acids did not change in microfiltered and pasteurized milk and in pasteurized milk. Compared with pasteurized milk, thecis-9,trans-11 conjugated linoleic acids, and ω-6/ω-3 ratio decreased by 43 and 12%, whiled32,d43, C18:3n-3, and C20:5n-3 increased by 52–57, 70, 3.2–5.8, and 4.8–2.6% in microfiltered and pasteurized milk, respectively. The contents ofcis-9,trans-11 conjugated linoleic acids, and cholesterols were higher on day 7 than on day 0, while the ω-6/ω-3 ratio and C22:6n-3 showed the opposite tendencies. Storage time did not affectd32(except for microfiltered and pasteurized milk) andd43. These highlighted that microfiltration has the potential to retain ω-3 fatty acids, decreased the ω-6/ω-3 ratio and maintain the stability of microfiltered and pasteurized milk shelf life. [ABSTRACT FROM AUTHOR]