Different fatty acid composition in central and peripheral adipose tissues of the American mink (Mustela vison)

Fatty acid (FA) composition in the intraabdominal (IAB), subcutaneous (SC) and peripheral adipose tissues of the semiaquatic American mink (Mustela vison) was examined in comparison to the diet by gas-liquid chromatography. There was a clear compositional gradient from the IAB via SC to peripheral adipose tissues and the anatomically different adipose tissues accumulated or metabolized FA selectively. The total lipids of the body appendages had smaller proportions of saturated (SFA) and larger proportions of monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) than the lipids of the trunk adipose tissues. Especially n-3 PUFA were enriched in the periphery. The appendages were also characterized with a high ratio of unsaturated FA to SFA, an increased Delta9-desaturation index and increased mean numbers of double bonds and carbon atoms in a FA molecule. The proportions of SFA and MUFA of the diet resembled the trunk adipose tissues while the dietary percentage of n-3 PUFA surpassed those of the trunk fat depots but was lower than those of the peripheral fats. These data confirm that the FA signatures of mammals reflect not only their dietary history but also metabolic modifications of ingested FA.     

Thermal Adaptation and Fatty Acid Composition of Major Phospholipids in the Plain Sculpin <Emphasis Type="Italic">Myoxocephalus jaok</Emphasis> at Different Temperatures of Natural Habitat

The composition of phospholipids (PLs), fatty acids (FAs), molecular species of major membrane lipids phosphatidylcholine (PC) and phosphatidylethanolamine (PE) as well as the cholesterol (CL) level in the gills and liver of the plain sculpin Myxocephalus jaok were analyzed at different habitat temperatures (18, 9, 0°C). Polar lipids and cholesterol were shown to be actively involved in adaptation of the plain sculpin to changes in environmental temperature. A decrease in temperature evoked multidirectional changes in the level of monoenoic (MUFA) and polyenoic (PUFA) FAs, ω-3 PUFA, etheric PLs, and in the unsaturation index (UI) of FAs in PC and PE of th e plain sculpin organs. Changes in the composition of PL molecular forms were unidirectional in all organs but showed some organ specificity. Thus, PC showed an increase in the total percentage of SFA/PUFA and MUFA/PUFA containing predominantly 20:5, 22:5 and 22:6 of PUFA and a decrease in the percentage of SFA/MUFA and PUFA/PUFA as well as in the level of alkylacyl forms of PC. PE showed an increase in the percentage of MUFA/PUFA and a decrease in that of SFA/PUFA and PUFA/PUFA as well as in the level of alkenylacyl forms of PE. Despite a close FA composition of PC and PE, the repertoire of their molecular forms differed in an organ- and temperature-dependent manner. Molecular mechanisms of thermal adaptation in the plain sculpin organs were traced more distinctly at the level of PC and PE molecular forms rather than in their FA spectrum.     

The effect of grazing on the fatty acid profile of longissimus thoracis muscle in Galician Blond calves

The objective of this work was to examine the effect of different levels of grazing on muscle nutritional fatty acid (FA) profile, including the beneficial n-3 polyunsaturated fatty acids (PUFA) and cis-9, trans-11 (cis-9, trans-11) 18:2 conjugated linoleic acid (CLA). Thirty male Galician Blond (GB) breed calves were randomly assigned to the following three grazing treatments: (1) continuous pasture grazing for 250 days (P); (2) 197-day grazing followed by a 50-day short period of concentrate-based finishing (PC) and (3) 57-day grazing followed by a 165-day long period of concentrate-based finishing (C). Calves kept sucking their mothers up to the time of slaughter. The slaughter weight was similar for all treatments (about 330 kg). Samples of the longissimus thoracis muscle were used for assessment of chemical composition by near infrared reflectance spectroscopy and FA profiles by gas chromatography. Muscle from C calves was fatter and had higher content in total FA, monounsaturated FA (MUFA), cis-9 18:1 than muscle from P calves, whereas PC muscle had generally intermediate values. No significant treatment difference for total saturated FAs (SFA) was found. Content of potentially beneficial n-3 PUFA (18:3n-3, 20:3n-3, 20:5n-3 and 22:6n-3), cis-9, trans-11 CLA and n-6:n-3 ratio were lower and PUFA : SFA ratio were higher in P than in both C and PC calves. Calves fed exclusively on pasture synthesised higher amounts of beneficial FA than calves finished on concentrate. A 50-day period of concentrate-based finishing was sufficient to offset the synthesis of beneficial FA from pasture grazing.     

Rearing system and oleic acid supplementation effect on carcass and lipid characteristics of two muscles from an obese pig breed

Quality of pork depends on genotype, rearing and pre- and post-slaughter conditions. However, no information is available on rearing system changes and oleic acid supplementation on carcass characteristics and fatty acid (FA) profile of pork from the Alentejano (AL) pig, an obese breed. This study evaluates the effects of feeding low (LO) or high oleic acid diets (HO) to AL pigs reared in individual pens (IND) or outdoor (OUT) with access to pasture. Carcass composition was obtained and longissimus dorsi and semimembranosus samples were collected to analyse chemical composition and neutral and polar intramuscular lipids FA profile by gas chromatography. Statistical analysis was performed by a two-way ANOVA for rearing system and diet effects. OUT-reared pigs presented leaner carcasses than IND-reared ones. Both muscles presented lower intramuscular lipid content in OUT-reared pigs. Treatments affected the FA profile of muscles. Overall, OUT-reared pigs presented lower n-6/n-3 FA ratios, whereas pigs fed the HO diet exhibited lower saturated fatty acids (SFA), higher monounsaturated fatty acids (MUFA) levels and lower thrombogenic indexes on neutral intramuscular lipids than LO-fed pigs. On the polar fraction, OUT-reared pigs presented lower SAT and n-6/n-3 FA ratio, and higher polyunsaturated fatty acids (PUFA) levels on both muscles. Pigs fed the HO diet exhibited higher MUFA and lower PUFA levels on both muscles, and lower SAT levels on semimembranosus. This study shows rearing system and oleic acid supplementation have complementary effects and influence carcass composition and the nutritional quality of meat.     

Evolution of the fatty acid profile of subcutaneous back-fat adipose tissue in growing Iberian and Landrace × Large White pigs

The lipid content and fatty acid (FA) profile in pig tissues are strongly influenced by genotype and nutrient supply, with implications in meat quality. The de novo lipid synthesis and pattern of FA unsaturation could be an important cause of variation in the overall efficiency of energy utilization among breeds. To test the effects of pig genotype and CP supply on the evolution of back-fat tissue FA profile throughout the growing and finishing stages, 32 Iberian (IB) and Landrace × Large White (LR × LW) barrows were offered one of two diets differing in CP content (13% or 17% as fed). A pair-fed procedure (0.8 × ad libitum intake of IB pigs) was used. Subcutaneous fat samples were taken at the dorso-lumbar region at ∼38, 50, 65, 90 and 115 kg BW. Higher proportions of total monounsaturated FA (MUFA; P < 0.01) and lower proportions of total saturated FA (SFA; P < 0.01 to 0.05) were found in the outer back-fat layer of pigs both at 50 and 115 kg BW. Pig genotype affected the FA composition of both subcutaneous back-fat layers. The proportions of C18:0 and SFA in fat tissue were higher in IB than in LR × LW pigs from 38 to 65 kg BW, especially in the outer layer. In addition, MUFA contents were higher in IB pigs at 115 kg BW in both layers (+5% on average; P < 0.01). Increased proportions of C18:2 n-6 and polyunsaturated FA (PUFA) were found in LR × LW pigs, irrespective of the stage of growth and back-fat layer (P⩽0.02). At 50 kg BW, pigs receiving the high-protein diet presented the highest C18:2 n-6, C18:3 n-3, C20:5 n-3 and PUFA contents. A significant genotype × CP content interaction was observed for C18:3 n-3 because of the increased concentration of this FA in LR × LW pigs when offered the 17% CP diet (P < 0.05). Higher C16:0 and SFA contents (+5%; P = 0.03) were found in pigs offered the 13% CP diet and slaughtered at 115 kg BW. There was a genotype × CP interaction for MUFA concentration because of the higher MUFA content observed in IB pigs offered the highest protein content diet (P = 0.03). Our results suggest that genetic variation in de novo lipid synthesis and pattern of FA unsaturation might contribute to explain differences in back-fat FA profile of IB and LR × LW pigs under identical nutritional management. They could be also relevant to explain the low efficiency of nutrient and energy utilization in the IB pig.     

Chemical composition of eggs of the Olive Ridley Lepidochelys olivacea (Testudines: Cheloniidae) and it's potential as a food source

The Olive Ridley is a worldwide distributed species with high nesting production per season, and in La Escobilla Oaxaca, México, there is a 70% of non-hatched eggs that are lost. In order to evaluate their potential use as a source for human and animal food products, their chemical composition was analyzed. Lyophilized egg samples from 25 turtles were obtained and were analyzed following the analytical methods for fatty acids, protein, fat, ash, moisture, amino acids, vitamins, cholesterol and microbiological agents. The analytical composition obtained was (g/100g): moisture (4.7), ash (3.8), protein (53.7), and fat (47.4). The essential amino acid (g aa/100g protein) content was: Ile (4.4), Lys (6.6), Leu (7.4), Met+Cys (8.8), Phe+Tyr (10.8). The vitamin content was: retinol (340 microg/100g), cholecalciferol (5.91 microg/100g) and 8.6 mg/100 tocopherol, 0.3 mg/100g thiamine and 1.1 mg/100g riboflavin. The total lipid content (TL), fatty acids (FA), and cholesterol (Chol) were divided into three groups based on the weight of the turtle: (TL) (44.3-48.7-49.1g/100g) and (Chol) (518.4-522.5 mg/100g-728.7). A total of 17 Saturated FA (SFA), 8 Monounsaturated FA (MUFA) and 11 Polyunsaturated FA (PUFA) were identified. The most abundant SFA (mg/100g) were: C14:0 (445-772), C16:0 (485-1263); MUFA: C16:1 (456-716), C18:1n-9c (904-1754), and PUFA: C20:4n-6 (105-217); two n-3 fatty acids were identified EPA (48-103) and DHA (97-189).There were significant differences (Fisher, p < 0.05) for: (Chol), total FA, SFA, MUFA, PUFAs and n-3 (EPA + DHA) FA. It was not detected any microbiological agent. In conclusion, lyophilized L. olivacea eggs are an option for its inclusion in the development of food products as they can be used as a high quality biological protein and n-3 fatty acid source for fortification and enrichment.     

N‐6 From Different Sources Protect From Metabolic Alterations to Obese Patients: A Factor Analysis

First, to analyze the interactions among fatty acids (FAs) from diet, plasma and subcutaneous and visceral adipose tissue (AT), and second, the relationship among FAs from these different sources and obesity‐related alterations in extreme obesity. We studied 20 extreme obese subjects. A food‐frequency questionnaire was used to determine the FA intakes. Serum and AT (subcutaneous and visceral) FA concentrations were determined by gas chromatography. Cardiometabolic risk parameters were assessed. Principal factor analysis was performed to define specific FA factors in the metabolic alterations. We found important associations among diet, plasma, and AT FA and cardiometabolic parameters. In this regard, it is interesting to highlight the negative associations between plasma cholesterol and dietary n‐3 FA. In the subcutaneous depot, as occurred in plasma, n‐6 and polyunsaturated FAs (PUFA) were negatively associated with triacylglycerols (TGs). Factor analysis revealed TGs as the unique cardiovascular risk parameter appearing in the first factor (F1), together with n‐6 (load factor = 0.94) and PUFA (0.91). Besides, n‐3 from diet and plasma appeared in the third factor inversely related to cholesterol, low‐density lipoprotein cholesterol (LDL‐c), and insulin. In an opposite way, dietary and AT trans FAs and saturated FA (SFA) were associated to an increase of the metabolic risk. We have shown, for the first time, the importance of n‐6 and PUFAs composition as protective factors against metabolic alterations in extreme obese subjects. These findings support current dietary recommendations to increase PUFA intakes and restrict saturated and trans FA intakes even in extreme obesity.     

Effects of Nucleotides Supplementation of Infant Formulas on Plasma and Erythrocyte Fatty Acid Composition: A Meta-Analysis

Objective

Nucleotides (NTs) have been added to infant formulas for several years due to their health benefits. However, studies have reported inconsistent findings regarding the association between NTs and fatty acid (FA) composition. A meta-analysis was performed to assess the effects of NTs supplementation of infant formula on erythrocyte and plasma FA composition.

Methods

Randomized controlled trials that evaluated the association between NTs supplementation and FA composition and were published before October 2014 were included. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated. Heterogeneity was assessed using Q and I ² tests.

Results

Eight studies (364 infants) were included in the meta-analysis. NTs supplementation did not affect the concentrations of total saturated FAs (SMD= 0.05; 95% CI= -0.23–0.32; P = 0.75) or total monounsaturated FAs (SMD= -0.01; 95% CI= -0.28–0.27; P = 0.95) in erythrocyte membranes. Erythrocyte total n-3 (SMD= 0.15; 95% CI= -0.11–0.41; P = 0.27) and n-6 PUFA (SMD= -0.16; 95% CI= -0.42–0.10, P = 0.22) concentrations did not increase with NTs supplementation. The concentrations of erythrocyte n-3 PUFA (18:3, 20:5, 22:5, and 22:6) and n-6 PUFA (18:2, 20:3, 20:4, and 22:4) were not affected by NTs supplementation. NTs significantly increased plasma concentrations of 18:2 n-6 (SMD= 0.90; 95% CI= 0.47–1.33; P < 0.0001), 20:3 n-6 (SMD= 0.56; 95% CI= 0.14–0.97; P = 0.009), and 20:4 n-6 PUFA (SMD= 0.92; 95% CI= 0.50–1.35; P < 0.0001), and significantly decreased the concentration of plasma 18:3 n-3 PUFA (SMD= -0.60; 95% CI -1.12 to -0.09; P = 0.02). No effect was obtained on plasma 20:2 n-6 PUFA concentrations (SMD= 0.06; 95 % CI, -1.03 to -0.2; P = 0.93).

Conclusions

Our meta-analysis revealed that NTs supplementation significantly increased plasma 18:2 n-6, 20:3 n-6, and 20:4 n-6 PUFA concentrations in infants, but did not affect erythrocyte FA composition.     

Dietary lipid quality and mitochondrial membrane composition in trout: responses of membrane enzymes and oxidative capacities

To examine whether membrane fatty acid (FA) composition has a greater impact upon specific components of oxidative phosphorylation or on overall properties of muscle mitochondria, rainbow trout (Oncorhynchus mykiss) were fed two diets differing only in FA composition. Diet 1 was enriched in 18:1n-9 and 18:2n-6 while Diet 2 was enriched in 22:6n-3. The FA composition of mitochondrial phospholipids was strongly affected by diet. 22:6n-3 levels were twice as high (49 %) in mitochondrial phospholipids of fish fed Diet 2 than in those fed Diet 1. 18:2n-6 content of the phospholipids also followed the diets, whereas 18:1n-9 changed little. All n-6 FA, most notably 22:5n-6, were significantly higher in fish fed Diet 1. Nonetheless, total saturated FA, total monounsaturated FA and total polyunsaturated FA in mitochondrial phospholipids varied little. Despite a marked impact of diet on specific FA levels in mitochondrial phospholipids, only non-phosphorylating (state 4) rates were higher in fish fed Diet 2. Phosphorylating rates (state 3), oxygen consumption due to flux through the electron transport chain complexes as well as the corresponding spectrophotometric activities did not differ with diet. Body mass affected state 4 rates and cytochrome c oxidase and F ₀ F ₁ ATPase activities while complex I showed a diet-specific effect of body mass. Only the minor FA that were affected by body mass were correlated with functional properties. The regulated incorporation of dietary FA into phospholipids seems to allow fish to maintain critical membrane functions even when the lipid quality of their diets varies considerably, as is likely in their natural environment.     

Genetic correlation estimates between beef fatty acid profile with meat and carcass traits in Nellore cattle finished in feedlot

The objective of this study was to estimate the genetic–quantitative relationships between the beef fatty acid profile with the carcass and meat traits of Nellore cattle. A total of 1826 bulls finished in feedlot conditions and slaughtered at 24 months of age on average were used. The following carcass and meat traits were analysed: subcutaneous fat thickness (BF), shear force (SF) and total intramuscular fat (IMF). The fatty acid (FA) profile of the Longissimus thoracis samples was determined. Twenty-five FAs (18 individuals and seven groups of FAs) were selected due to their importance for human health. The animals were genotyped with the BovineHD BeadChip and, after quality control for single nucleotide polymorphisms (SNPs), only 470,007 SNPs from 1556 samples remained. The model included the random genetic additive direct effect, the fixed effect of the contemporary group and the animal’s slaughter age as a covariable. The (co)variances and genetic parameters were estimated using the REML method, considering an animal model (single-step GBLUP). A total of 25 multi-trait analyses, with four traits, were performed considering SF, BF and IMF plus each individual FA. The heritability estimates for individual saturated fatty acids (SFA) varied from 0.06 to 0.65, for monounsaturated fatty acids (MUFA) it varied from 0.02 to 0.14 and for polyunsaturated fatty acids (PUFA) it ranged from 0.05 to 0.68. The heritability estimates for Omega 3, Omega 6, SFA, MUFA and PUFA sum were low to moderate, varying from 0.09 to 0.20. The carcass and meat traits, SF (0.06) and IMF (0.07), had low heritability estimates, while BF (0.17) was moderate. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with BF were 0.04, 0.64 and ?0.41, respectively. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with SF were 0.29, ?0.06 and ?0.04, respectively. The genetic correlation estimates between SFA sum, MUFA sum and PUFA sum with IMF were 0.24, 0.90 and ?0.67, respectively. The selection to improve meat tenderness in Nellore cattle should not change the fatty acid composition in beef, so it is possible to improve this attribute without affecting the nutritional beef quality in zebu breeds. However, selection for increased deposition of subcutaneous fat thickness and especially the percentage of intramuscular fat should lead to changes in the fat composition, highlighting a genetic antagonism between meat nutritional value and acceptability by the consumer.     

Dietary polyunsaturated fatty acids alter myocardial protein kinase C expression and affect cardioprotection induced by chronic hypoxia

We examined the influence of dietary fatty acid (FA) classes on the expression of protein kinase C (PKC) delta and epsilon in relation to the cardioprotective effects of chronic intermittent hypoxia (CIH). Adult male Wistar rats were fed a nonfat diet enriched with 10% lard (saturated FA [SFA]), fish oil (n-3 polyunsaturated FA [n-3 PUFA]), or corn oil (n-6 PUFA) for 10 weeks. After 4 weeks on the diet, each group was divided into two subgroups that were either exposed to CIH in a barochamber (7000 m, 8 hrs/ day) or kept at normoxia for an additional 5-6 weeks. A FA phospholipid profile and Western blot analysis of PKC were performed in left ventricles. Infarct size was assessed in anesthetized animals subjected to 20-min coronary artery occlusion and 3-hr reperfusion. CIH decreased the n-6/n-3 PUFA ratio in all groups by 23% independently of the initial value set by various diets. The combination of n-3 diet and CIH had a stronger antiarrhythmic effect during reperfusion than the n-3 diet alone; this effect was less pronounced in rats fed the n-6 diet. The normoxic n-6 group exhibited smaller infarctions (by 22%) than the n-3 group. CIH decreased the infarct size in n-3 and SFA groups (by 20% and 23%, respectively) but not in the n-6 group. Unlike PKC epsilon, the abundance of PKC delta in the myocardial particulate fraction was increased by CIH except for the n-6 group. Myocardial infarct size was negatively correlated (r=- 0.79) with the abundance of PKC delta in the particulate fraction. We conclude that lipid diets modify the infarct size-limiting effect of CIH by a mechanism that involves the PKC delta-dependent pathway.     

Effect of sex,dietary glycerol or dietary fat during late fattening,on fatty acid composition and positional distribution of fatty acids within the triglyceride in pigs

The effect of sex, source of saturated fat (lard v. palm oil) and glycerol inclusion in the fattening diet on composition and fatty acid positional distribution in the triglyceride molecule was studied in pigs from 78 to 110 kg BW. Average daily gain and carcass characteristics, including ham and loin weight, were not affected by dietary treatment but sex affected backfat depth (P<0.01). A significant interaction between sex and glycerol inclusion was observed; dietary glycerol increased lean content in gilts but not in barrows (P<0.05 for the interaction). Individual and total saturated fatty acid (SFA) concentrations were greater in barrows than in gilts. In contrast, the concentration of total polyunsaturated fatty acids (PUFA) and of C18:2n-6, C18:3n-3, C20:3n-9 and C20:4n-6 in the intramuscular fat (IMF) was higher (P<0.05) in gilts than in barrows. Sex did not affect total monounsaturated fatty acids (MUFA) concentration in the IMF. The proportion of SFA in the subcutaneous fat (SF) was higher in barrows than in gilts (P<0.001). Within the individual SFA, sex affected only the concentrations of C14:0 and C16:0 (P<0.001). Dietary fat did not affect total SFA or PUFA concentrations of the IMF but the subcutaneous total MUFA concentration tended to be higher (P=0.079) in pigs fed lard than in pigs fed palm oil. Dietary glycerol increased total MUFA and C18:1n-9 concentration in the IMF and increased total MUFA and decreased C18:2n-6, C18:3n-3 and total PUFA concentrations in the SF. The data indicate that altering the fatty acid composition of the triglyceride molecule at the 2-position, by dietary intervention during the fattening phase, is very limited.     

Effects of supplementation of maize silage diets with extruded linseed, vitamin E and plant extracts rich in polyphenols, and morning v. evening milking on milk fatty acid profiles in Holstein and Montbéliarde cows

The aim of this study was to evaluate the effects on dairy performance and milk fatty acid (FA) composition of (i) supplementation with extruded linseed (EL), (ii) supplementation with synthetic or natural antioxidants, namely vitamin E and plant extracts rich in polyphenols (PERP), (iii) cow breed (Holstein v. Montbéliarde) and (iv) time of milking (morning v. evening). After a 3-week pre-experimental period 24 lactating cows (12 Holstein and 12 Montbéliarde) were divided up into four groups of six cows: the first group received a daily control diet (diet C) based on maize silage. The second group received the same diet supplemented with EL (diet EL, fat level approximately 5% of dietary dry matter (DM)). The third group received the EL diet plus 375 IU/kg diet DM of vitamin E (diet ELE). The fourth group received the ELE diet plus 10 g/kg diet DM of a PERP mixture (diet ELEP). Compared with the diet C, feeding EL-rich diets led to lower concentrations of total saturated FA (SFA) and higher concentrations of stearic and oleic acids, each trans and cis isomer of 18:1 (except c12-18:1), non-conjugated isomers of 18:2, some isomers (c9t11-, c9c11- and t11t13-) of conjugated linoleic acid (CLA), and 18:3n-3. The vitamin E supplementation had no effect on milk yield, milk fat or protein percentage and only moderate effects on milk concentrations of FA (increase in 16:0, decreases in 18:0 and t6/7/8-18:1). The addition of PERP to vitamin E did not modify milk yield or composition and slightly altered milk FA composition (decrease in total saturated FA (SFA) and increase in monounsaturated FA (MUFA)). The minor effects of vitamin E may be partly linked to the fact that no milk fat depression occurred with the EL diet. During both periods the Holstein cows had higher milk production, milk fat and protein yields, and milk percentages of 4:0 and 18:3n-3, and lower percentages of odd-branched chain FA (OBCFA) than the Montbéliarde cows. During the experimental period the Holstein cows had lower percentages of total cis 18:1, and c9,c11-CLA, and higher percentages of 6:0, 8:0, t12-, t16/c14- and t13/14-18:1, and 18:2n-6 than Montbéliarde cows because of several significant interactions between breed and diet. Also, the total SFA percentage was higher for morning than for evening milkings, whereas those of MUFA, total cis 18:1, OBCFA and 18:2n-6 were lower. Extruded linseed supplementation had higher effect on milk FA composition than antioxidants, breed or time of milking.     

Fatty acid composition in the white muscle of Cottoidei fishes of Lake Baikal reflects their habitat depth

Lake Baikal is a unique freshwater environment with maximum depths over 1600 m. The high water pressure at the lakebed strengthens the solidifying effect of low water temperature on animal tissue lipids, and thus the effective temperatures in the depths of the lake equal subzero temperatures in shallow waters. Cottoidei species has colonized the different water layers of the lake, and developed different ecology and physiology reflected in their tissue biochemistry. We studied by gas chromatography the composition of fatty acids (FAs), largely responsible for tissue lipid physical properties, in the white muscle tissue of 13 species of the Cottoidei fish; five benthic abyssal, six benthic eurybathic and two benthopelagic species. The FA profiles reflected habitat depth. The muscles of the deepest living species contained little polyunsaturated FAs (PUFAs) and were instead rich in monounsaturated FAs (MUFAs), which may be due to occasional weak food web links to the PUFA-rich primary producers of the photic water layer, high MUFA supply from their benthic diet, and conversion of saturated FAs (SFAs) to MUFAs in the tissues of the fish. Despite the MUFA percentage among the abyssal species reached even 50% (by weight) of total FAs, the PUFA percentage still remained above 20% in every species. The muscle MUFA/SFA ratio correlated negatively with the PUFA content of the fish muscle, suggesting viscosity control integrating the fluidity contributions from the dietary PUFAs and potentially endogenous MUFAs.     

Changes in diet, body mass and fatty acid composition during pre-hibernation in a subtropical bat in relation to NPY and AgRP expression

Prior to hibernation, mammals accumulate large amounts of fat in their bodies. In temperate mammalian species, hibernation is improved by increasing the levels of poly-unsaturated fatty acids (PUFA) in the body. The saturation of fatty acids (FA) in both white adipose tissue (WAT) and membrane phospholipids of mammals often reflects their diet composition. We found that the greater mouse-tailed bat (Rhinopoma microphyllum) accumulates large amounts of fat at the end of summer by gradually shifting to a fat-rich diet (queen carpenter ants, Camponotus felah). PUFA are almost absent in this diet (<1 % of total FA), which contains a high fraction of saturated (SFA) and mono-unsaturated (MUFA) fatty acids. We found similar low levels of PUFA in mouse-tailed bat WAT, but not in their heart total lipids. The expression of two appetite-stimulating (orexigenic) hypothalamic neuropeptides, AgRP and NPY, increased in parallel to the shift in diet and with fat gain in these bats. To the best of our knowledge, this is the only documented example of specific pre-hibernation diet in bats, and one which reveals the most saturated FA composition ever documented in a mammal. We suggest that the increase in expression levels of NPY and AgRP may contribute to the observed diet shift and mass gain, and that the FA composition of the bat’s specialized diet is adaptive in the relatively high temperatures we recorded in both their winter and summer roosts.     

Increased arachidonic acid concentration in the brain of Flinders Sensitive Line rats, an animal model of depression

Depression may be associated with impaired membrane PUFA composition, especially decreased n-3 PUFA. This assumption has not been tested at the level of brain tissue. Moreover, most studies were confounded by dietary variability. We examined the FA composition of selected brain areas in an animal model of depression, the Flinders Sensitive Line (FSL) rat, and compared the findings with those in controls fed identical diets. In all brain regions studied, the concentration of arachidonic acid (AA) was significantly higher in the FSL rats: in the hypothalamus by 21%, in the nucleus accumbens by 24%, in the prefrontal cortex by 31%, and in the striatum by 23%. No significant differences were observed for n-3 PUFA or for the saturated and monounsaturated FAs. Our results confirm the existence of altered brain PUFA composition in an animal model of depression. The finding of increased AA, an n-6 PUFA, rather than decreased n-3 PUFA, emphasizes the importance of both PUFA families in the pathophysiological processes underlying depression. The FSL rat is a useful tool for further elucidation of the FA disturbances in depression.     

Effect of Dietary Mono- and Polyunsaturated Fatty Acids on the Fatty Acid Composition of Pigs' Adipose Tissues

In two experiments with growing-finishing pigs six different dietary fats were added to a conventional diet (control - C) to study the effects of dietary monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) on the fatty acid composition of backfat and kidney fat at similar amounts of double bonds in feed (Exp. 1:7% pork fat - PF, 4.95% olive oil - OO, 3.17% soybean oil - SO) or a constant amount of 5% of processed fats (Exp. 2: partially hydrogenated fat - SAT, fractionated pork fats: olein - OLE, stearin - STE). Compared with the control, PUFA were only slightly increased in backfat of pigs fed PF, OLE, STE or OO, although dietary PUFA intake was up to 70% higher. With SO PUFA were significantly increased in adipose tissues, predominantly at the expense of MUFA. Consequently, a non-linear relationship was found between PUFA intake and proportion in backfat. MUFA were incorporated at the expense of SFA, therefore, adipose tissues of OO fed animals were lowest in SFA. Despite comparable amounts of double bonds in feed (Exp. 1), the degree of unsaturation measured as fat score (sum of double bonds) was in the order SO > OO > PF > C. In contrast, the proportion of SFA was C > PF = SO > OO. Regarding the decisive role of SFA for fat consistency it may be concluded that MUFA should also be considered in feeding recommendations for pigs. Furthermore, in case of a high dietary supply of MUFA, a simple index of double bonds might not be sufficiently conclusive to judge pig fat quality.     

越冬胁迫对草鱼抗氧化能力及脂肪酸组成的影响

为了探讨草鱼(Ctenopharyngodon idellus)越冬期间氧化应激状况及其与组织脂肪酸比例变化的关联性,将草鱼[初始体重(1053.33±16.11) g]分别置于室外水泥培育池,自然越冬处理0、1周、2周、4周、8周、12周和16周后,进行生物学性状指标,肝胰脏、肌肉、前肠、脂肪组织和血清抗氧化能力指标及肝胰脏、肌肉、脂肪组织脂肪酸比例的测定,同时进行了抗氧化能力指标与脂肪酸比例间的关联性分析。结果表明,在越冬期间,草鱼机体体重、肝胰脏重量、肥满度、肝体比、脏体比、肠体比和腹腔脂肪指数均发生显著下降(P<0.05);但是肾指数和脾指数显著上升(P>0.05)。氧化胁迫应激最大的3个组织分别是脂肪组织、肝胰脏和肌肉。肝胰脏PUFA比例对总体脂肪酸比例产生了主要的影响(主成分载荷特征值>0.5),肌肉C18:2n-6和C16:0比例对总体脂肪酸组成产生主要影响,脂肪组织中的PUFA、n-6PUFA、SFA和MUFA比例对总体脂肪酸比例产生了主要影响;关联分析表明草鱼脂肪组织中SFA在越冬期间供应能量同时,与氧化应激乃至机体损伤显示正相关关联性,肌肉中PUF...     

Spatial and temporal variation of the fatty acid composition of Patella spp. (Gastropoda: Prosobranchia) soft bodies and gonads

This study evaluated the effects of season and spatial distribution on the fatty acid composition of Patella depressa gonads and Patella spp. soft body tissue. The results show that the quantitatively most important fatty acids were the saturated fatty acids (SFA) 16:0, 14:0 and 18:0; the monounsaturated fatty acids (MUFA) 18:1(n-7), 18:1(n-9), 16:1(n-7) and 20:1(n-9) and the polyunsaturated fatty acids (PUFA) eicosapentaenoic acid (EPA 20:5(n-3)), and arachidonic acid (ARA 20:4(n-6)). P. depressa and P. ulyssiponensis soft body fatty acid profiles revealed significant differences between sexes; males showed significantly higher percentages of PUFA, highly unsaturated fatty acids (HUFA), (n-3) fatty acids and ARA, while in females significantly higher proportions of MUFA were found. Analysis of variance on the fatty acid composition of P. depressa gonads revealed significant differences between sexes, which were more marked than when the whole body was analysed. Males showed a significantly higher percentage of PUFA, HUFA, fatty acids from the (n-3) and (n-6) series, ARA and EPA, while females were seen to have higher proportions of SFA, MUFA and total fatty acid methyl esters (FAME). Some variability was seen to occur due to shore location and seasons, but these effects were not so obvious.