Perturbation of phospholipid and triacylglycerol fatty acid positional location in the heart of rats depleted of n-3 long-chain polyunsaturates

Rats depleted of long-chain polyunsaturated n-3 fatty acids (n-3–D) display several features of the metabolic syndrome, including obesity, liver steatosis, insulin resistance, hypertension, and cardiac hypertrophy. In this study, the heart phospholipid (PL) and triacylglycerol (TG) fatty acid content and pattern were compared between female control rats (C) and n-3–D rats. The sole n-3 fatty acids found in n-3–D rats, C22:5(n-3) and C22:6(n-3), were 10 to 20 times lower than in C. The total fatty acid content of PL was lower in n-3–D rats than C. No ectopic TG accumulation was found in n-3–D rats. In both PL and TG, the C16:0/C16:1(n-7) and C18:0/C18:1(n-9) ratios suggested increased Δ9-desaturase activity in n-3–D rats. The PL C18:2(n-6)/C20:4(n-6) and C20:4(n-6)/C22:4(n-6) ratios were also lower in n-3–D rats than C. Prior intravenous injection of a medium-chain TG:fish oil emulsion to n-3–D rats 60 to 120 minutes before killing augmented the PL content in C22:5(n-3) and C22:6(n-3), minimized the age-related decrease in the PL C18:1(n-9) relative content, and increased the TG C22:4(n-6) content. The alteration of cardiac function in n-3–D rats and its improvement after injection of medium-chain TG:fish oil emulsion coincides with parallel changes in heart lipid fatty acid content and pattern.     

Metabolism of some radiolabeled essential fatty acids in isolated rat hepatocytes is affected by dietary ethanol.

The metabolism of the essential fatty acids [1-14C]20:4n-6, [1-14C]20:5n-3 and [1-14C]22:6n-3 was studied in rat hepatocytes fed ethanol in two different diets. Using a diet with a low lipid content ethanol (1) reduced the elongation of eicosapentaenoic acid, (2) reduced the esterification of docosahexaenoic acid (DHA) in phospholipids (PL), (3) increased the oxidation of DHA, (4) increased the ratio of esterification of DHA in phosphatidylethanolamine (PE) compared to phosphatidylcholine (PC) (PE/PC ratio), (5) altered the formation of PL molecular species, and (6) induced a decrease in the endogenous content of the hepatocytes of arachidonic acid and linoleic acid and an increase in oleic acid, 20:3n-9 and DHA. Using a high lipid diet, only the above-mentioned effect (4) was induced by ethanol, not the effects (1)-(3) and (5)-(6).     

Dietary n-3 and n-6 fatty acids alter avian metabolism: molecular-species composition of breast-muscle phospholipids

The effects of diets high in n-3 polyunsaturated fatty acids (PUFA; provided by fish oil), n-6 PUFA (sunflower oil) or in more-saturated fatty acids (tallow) on the distribution of subclasses of choline phospholipids (PC) and ethanolamine phospholipids (PE) from the breast muscle of broiler chickens were examined. Supplementation with the different fatty acids had no effect on the distribution of phospholipid subclasses. Feeding sunflower oil or tallow gave a molecular-species profile similar in both fatty acid subtype and proportion. In the diacyl PC phospholipids, 16 : 0-18 : 1n-9 and 16 : 0-18 : 2n-6 accounted for approximately 60 % of the total molecular species, whereas for the alkylenyl PC the predominant species were 16 : 0-18 : 1n-9 and 16 : 0-20 : 4n-6. Of the diacyl PE the dominant species was 18 : 0-20 : 4n-6 which accounted for 50 % of the molecular species, and of the alkylenyl PE the dominant species were 16 : 0-18 : 1n-9, 16 : 0-20 : 4n-6 and 18 : 0-20 : 4n-6. Supplementation with fish oil significantly increased levels of both eicosapentaenoic acid (20 : 5n-3) and docosahexaenoic acid (22 : 6n-3) in PC and PE when compared with either sunflower oil or tallow supplementation. The increase in the n-3 PUFA incorporation was associated with a corresponding decrease in the proportion of arachidonic acid (20 : 4n-6) in both PC and PE. Different dietary fats induce different patterns of fatty acid incorporation and substitution in the sn-2 position of the diacyl and alkylenyl PC and PE of avian breast muscle, and this finding is indicative of selective acyl remodelling in these two phospholipids.     

Total Lipid,Cholesterol, and Fatty Acids of Farmed Freshwater Prawn (Macrobrachium rosenbergii) and Wild Marine Shrimp (Penaeus brasiliensis,Penaeus schimitti,Xiphopenaeus kroyeri)

Total lipid, cholesterol, and fatty acids were determined in freshwater prawn (Macrobrachium rosenbergii) and in wild marine shrimp (Penaeus brasiliensis, Penaeus schimitti, Xiphopenaeus kroyeri). The concentration of total lipid was 0.9–1.0 g/100 g in the marine species and 1.1 g/100 g in freshwater M. rosenbergii. No significant difference was observed in terms of origin of samples and size. Cholesterol levels ranged from 114 in Penaeus brasiliensis to 139 mg/100 g in M. rosenbergii. Size had a significant influence in P. brasiliensis but not in P. schimitti. Shrimp (same species and size) from two states did not differ significantly. The principal fatty acids in the marine shrimp were C16:0, C20:5n-3, C22:6n-3, C18:1n-9, C18:0, 16:1n-7, 20:4n-6, and 18:1n-7. In the freshwater prawn M. rosenbergii, the major fatty acids were C16:0, C20:5n-3, C18:1n-9, C18:0, C22:6n-3, C18:2n-6, C17:0, and C18:1n-7. Quantitatively, M. rosenbergii differed markedly from the other species, followed by Xiphopenaeus kroyeri. In general, origin of samples and size did not have a significant influence.     

Alpha-linolenic acid content of commonly available nuts in Hangzhou

The total lipid content of eight species of nuts available in Hangzhou ranged from 49.5 g/100 g weight in Cannabis sativa to 75.4 g/100 g in walnut. The predominant content of lipid is triacylglycerol, ranging from 91.1% in Cannabis sativa to 98.4% in macadamia. There were two polyunsaturated fatty acids (PUFA) in all nuts analyzed; 18:2n-6 and 18:3n-3. The content of 18:3n-3 ranging from 0.2% in almond to 15.2% in Cannabis sativa, 18:2n-6 ranged from 2.5% in macadamia to 61.6% in pine nut. The proportion of total PUFA in analyzed eight nut species ranging from 2.8% in macadamia to 71.7% in walnut (p < 0.001). Monounsaturated fatty acid composition ranged from 18.0% in Cannabis sativa to 82.6% in macadamia (p < 0.001). The proportion of saturated fatty acid ranged from 7.4% in filbert to 14.7% of total fatty acids in macadamia (p < 0.001). No C20 fatty acids were detected in any of the samples in the present study. The lipids content and fatty acid compositions in analyzed samples were varied between nut species. Cannabis sativa and walnut contained relatively high 18:3n-3, consumption of several these nuts each day can contribute to n-3 PUFA intake, especially for the vegetarian population.     

Dietary n-3 polyunsaturated fatty acids: modification of rat cardiac lipids and fatty acid composition

The effects of 5, 10 and 20% dietary menhaden oil (MO) on the composition of heart lipid classes and fatty acids were studied. Male Sprague-Dawley rats were fed ad libitum 0, 5, 10 and 20% MO for 3 wk. The heart phosphoglyceride content and composition and cholesterol were unchanged by dietary MO. A nonlinear dose-response relationship was observed between dietary MO levels and fatty acid compositional changes. Cardiolipin, choline (PC), ethanolamine (PE) and serine/inositol (PS/PI) phosphoglycerides showed an incorporation of n-3 fatty acids, eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3), between the control and 5% MO group, a plateau between the 5 and 10% MO groups and a further increase at the 20% MO level. The initial reduction in 20:4n-6 content remained unchanged as dietary MO increased except in PE where a further reduction was found at the 20% MO level. Dietary MO did not significantly change the 20:4n-6 content in neutral lipids. Linoleic acid content was most resistant to dietary MO removal. The level of 18:2n-6 was significantly lowered in heart PC when rats were fed 10% MO. No significant differences were found in PS/PI. In PE and NL significant differences occurred only when rats were fed 20% MO. The significant fatty acid modifications of heart lipid and PL found between the control and lowest level of dietary MO (5%) suggest that dietary fish oil supplementation in human diets may not be required for this effect.     

Adipose fatty acid composition and rate of incorporation of alpha-linolenic acid differ between normal and lipoprotein lipase-deficient cats

Normal adiposity occurs in humans and mice deficient of adipose lipoprotein lipase (LPL) activity. Subnormal adiposity found in LPL-deficient cats is indicative of limited de novo synthesis of fatty acids (FAs). In 14 LPL-deficient (3.0 +/- 0.1 kg) and 8 normal (3.7 +/- 0.1 kg) queens, FAs in triacylglycerol (TAG), phospholipid (PL), and nonesterified FAs (NEFAs) of plasma and inguinal subcutaneous adipose were determined before and after (d 38, 61, 110, 117, and 251) dietary linseed oil supplementation (30 g/kg). By d 60, LPL-deficient queens gained body weight (+0.4 +/- 0.1 kg), developed normal body fat mass (25 +/- 2%), and were enriched in 18:3(n-3) in their plasma and adipose lipids. Adipose TAG 18:3(n-3) enrichment in LPL-deficient queens was subnormal at all sampling times and, as observed in normal queens, apparently not equilibrated by d 251. Adipose FA profiles in TAG but not PL were substantially different (P < 0.05) between LPL-deficient and normal queens; the 16:0 to 18:2(n-6) ratio was high in LPL-deficient (2.4-4.4) relative to normal queens (1.0-1.4). In LPL-deficient queens, fed-state plasma NEFA (n-6) and (n-3) enrichments were similar to those in adipose TAG, and plasma NEFA concentration was high (0.62 +/- 0.05 mmol/L) and similar to that in normal queens after withholding diet for 16 h. These data indicate that LPL deficiency in cats reduces dietary FA storage efficiency, favors storage of saturated over unsaturated FAs, and stimulates de novo FA synthesis substantive enough to support normal adiposity.     

Effects of casein and soy-protein on alpha-linolenic acid metabolism in rats.

In order to study the effects of different proteins on alpha-linolenic acid (alpha-LnA) metabolism, rats were given the diet added respectively with milk casein and soy-protein isolate (SPI) as sources of proteins and perilla oil as a source of lipid. The results obtained are as follows. The ratio of (C20:3 + C20:4)/C18:2 in liver microsomal PL, liver PE fraction, and kidney PE and PC fractions was significantly lowered by the SPI treatment when compared to the casein treatment, similarly to the already established results. In the liver microsomal PL and PE and PC fractions of liver and kidney in rats treated with SPI, there was also observed a significant decrease or a decrease tendency in the (C20:4 + C20:5)/C18:3 ratio. A similar tendency was again shown in the sigma (n-3)M/C18:3 ratio indicating metabolic conversion from C18:3(n-3) to C22:6. On the other hand, contrary to the ratios of (C20:3 + C20:4)/C18:2, sigma (n-3)M/C18:3, and (C20:3 + C20:5)/C18:3, the (C22:5 + C22:6)/C20:5 ratio which is the parameter for metabolic conversion of C20:5(n-3) was elevated in the PE and PC fraction of liver, heart and kidney in the SPI group compared to the casein group. Then, further analysis of the metabolic process from C20:5 to C22:6 showed that the C22:5/C20:5 ratio increased while the C22:6/C22:5 ratio decreased in the SPI group compared to the casein group. Based on these results, it is assumed that the metabolic process from C18:3(n-3) to C20:5(n-3) and from C22:5 to C22:6 is affected by SPI but that the elongation process from C20:5(n-3) to C22:5(n-3), on the contrary, is rather accelerated by SPI.     

The effect of food deprivation on the fatty acid and lipid profile of red seabream (Pagrus major) larvae

Under conditions of food deprivation the lipid fraction of red seabream (Pagrus major) larvae shows patterns of conservation or loss in the profile of fatty acids and lipids. These changes were used for qualitative formulation of the dietary requirements of this species. Red seabream larvae were deprived of food for 5 d after hatching. Their lipid was extracted, weighed and analysed by gas-liquid chromatography and iatroscan for the presence of twenty-four fatty acids including n-3 polyunsaturated fatty acids (PUFA), four polar lipids (PL) and four neutral lipids (NL). The results show an exponential decline in lipids with food deprivation, from a mean of 27.7 down to 11.8 mg/g wet larvae weight (LW). This loss could mainly be attributed to a decline in NL from 22.4 to 7.7 mg/g LW, in triacylglycerols, from 21 to 1 mg/g LW, and a change in cholesterol, from 1.3 to 4.2 mg/g LW after 5 d of food deprivation. PL declined from 5.3 to 4.1 mg/g LW in this period. The chief components of this fraction were phosphatidyl choline, and phosphatidyl ethanolamine. Among the fatty acids, the chief decline was observed in saturates and monoenes. Carbon chain lengths of 14 to 18 made up 18.2 mg/g LW in hatched larvae, but only 4.8 mg/g LW in larvae which were deprived of food for 5 d after hatching. n-3 PUFA were lost at a slower rate, from 5.4 to 3.5 mg/g LW for the same period, suggesting that they were conserved. Finally, early larvae of red seabream showed a reduced rate of loss of n-6 relative to n-9 fatty acids, suggesting that the latter were used preferentially as an energy source.     

Changes in plasma fatty acid composition after intake of a standardised breakfast in prepubertal obese children

Obese patients typically show a pattern of dyslipidaemia and changes in plasma fatty acid composition reflecting abnormalities in lipoprotein metabolism and dietary habits. Animals and obese adults have been widely studied; however, contradictory results have been published in children. The objective was to assess changes in plasma fatty acid composition in total plasma lipids and plasma lipid fractions in obese prepubertal children compared with those of normal weight and to evaluate changes in postprandial plasma fatty acids during a 3 h period after intake of a standardised breakfast. The study was a case-control study with thirty-four obese and twenty normal-weight prepubertal children (Tanner 1). Anthropometric and metabolic variables and fatty acid concentrations were measured in plasma and its fractions. Liquid chromatography was used to separate lipid fractions and GLC to quantify fatty acids. Plasma total fatty acids (TFA), SFA, MUFA and PUFA concentrations were higher in obese than in control children. Except for 18 : 0, 18 : 3n-3, 20 : 4n-6 and n-3 PUFA, all fatty acids in TAG were also elevated in the obese group. Fatty acids 16 : 1n-7, 18 : 0, 18 : 1n-9, 20 : 2n-6, TFA and MUFA significantly decreased between the 2nd and 3rd hour in normal-weight v. obese children. The concentration of 16 : 1n-7 was positively and the proportion of 20 : 4n-6 inversely associated with a significant increase in risk of obesity. Obese prepubertal children show an altered plasma fatty acid profile and concentrations, mainly related to the TAG fatty acid profile, with a lower clearance of fatty acids v. normal-weight prepubertal children.     

Dietary eritadenine and ethanolamine depress fatty acid desaturase activities by increasing liver microsomal phosphatidylethanolamine in rats

The effects of eritadenine, a constituent of the Lentinus edodes mushroom, and ethanolamine, the base constituent of phosphatidylethanolamine (PE), on fatty acid desaturase activities and lipid profiles were investigated comparatively in rats. Rats were fed a control diet or a diet supplemented with either eritadenine (0.05 g/kg) or ethanolamine (8 g/kg) for 14 d. Eritadenine and ethanolamine had marked hypocholesterolemic effects. The concentration of liver microsomal PE was significantly increased and the ratio of phosphatidylcholine (PC) to PE was significantly decreased by both eritadenine and ethanolamine. These changes in phospholipid profile were also observed in the mitochondria and plasma membranes in the liver. The activities of the Delta5-, Delta6- and Delta9-desaturases in liver microsomes were significantly decreased by eritadenine and ethanolamine; there was a significant correlation between the activity of Delta5- or Delta6-desaturase and the proportion of PE in the total phospholipids or the PC/PE ratio. Reflecting decreased Delta5- and Delta6-desaturase activities, the 20:4(n-6)/18:2(n-6) ratio was significantly decreased by eritadenine and ethanolamine in PC of the liver microsomes, mitochondria and plasma membranes. Although the 20:4(n-6)/18:2(n-6) ratio of liver microsomal PE was also significantly decreased by eritadenine and ethanolamine, the fatty acid composition of phosphatidylinositol and phosphatidylserine was less affected by these compounds. Eritadenine and ethanolamine increased the proportion of 16:0-18:2 and decreased the proportion of 18:0-20:4 in liver PC. The results suggest that dietary eritadenine and ethanolamine might lead to decreases in desaturase activities and changes in fatty acid and molecular species composition of PC through an increase in liver microsomal PE.     

Seasonal comparison of wild and farmed brown trout (Salmo trutta forma fario L., 1758): crude lipid, gonadosomatic index and fatty acids

Brown trout is one of the most preferred wild freshwater fish species in the east Black Sea region (Turkey) due to its nutritional value and palatable aroma as well as being popular for sport fishing. In this research, seasonal variations in the crude lipid, gonadosomatic index and fatty acid composition of wild and farmed brown trout were investigated. The spawning period of wild and farmed brown trout appears to be from August to October and from October to January, respectively. The mean crude lipid content in farmed brown trout (3.62%) was significantly higher (P≤0.05) than that of wild brown trout (2.80%). Significant seasonal differences (P≤0.05) in crude lipid content were observed in both fish. The percentage of total saturated fatty acids was similar (P≥0.05) in both fish. Total polyunsaturated fatty acids were higher (P≤0.05) in the wild brown trout compared with the farmed brown trout, while its total monounsaturated fatty acids content was lower (P≤0.05). The muscle lipids of wild fish contained significantly (P≤0.05) higher percentages of C16:1n-7, C17:1n-7, C18:3n-3, C20:2n-6, C20:4n-6, C20:5n-3 and C22:2n-6 fatty acids and contained lower percentages of C14:0, C18:1n-9, C18:2n-6, C20:1n-9, C24:1n-9 and C22:6n-3 fatty acids than farmed fish. The total amounts of n-3 fatty acids in wild fish were higher than in farmed fish, but total amounts of n-6 fatty acids in farmed fish were higher than in wild fish. The n3/n6 proportion in wild fish was higher than that of farmed fish.     

Umbilical venous-arterial plasma composition differences suggest differential incorporation of fatty acids in NEFA and cholesteryl ester pools

The developing fetus requires an adequate supply of fatty acids, in particular PUFA, for optimal growth and development. Little is known about the transfer of fatty acids by the placenta into the fetal circulation. However, the molecular form in which fatty acids are transferred into the fetal circulation may influence their metabolism and hence their availability to specific tissues. The aim of the present study was to determine which lipid pools in the fetal circulation become enriched in fatty acids from the placenta by comparing the fatty acid compositions of individual lipid pools between umbilical venous (UV) and umbilical arterial (UA) plasma. Plasma from the UV and UA was collected after delivery from ten uncomplicated pregnancies, and the fatty acid composition of each lipid class was determined by GC. Total NEFA concentration in the UV was twofold higher than in the UA (P < 0·05) due to enrichment in 16 : 0, 16 : 1n-7, 18 : 1n-9, 18 : 1n-7, 18 : 2n-6, 20 : 3n-6, 20 : 4n-6, 24 : 0 and 22 : 6n-3. Total cholesteryl ester concentration was twofold higher in the UV than in the UA (P < 0·05) due to enrichment in 16 : 0, 16 : 1n-7, 18 : 0, 18 : 1n-9, 18 : 1n-7, 18 : 2n-6 and 20 : 4n-6. There were no significant UV-UA differences in the total concentration or composition of TAG or phosphatidylcholine. The present study demonstrates differential enrichment across the placenta of fatty acids into specific lipid pools in the fetal circulation. Such partitioning may facilitate supply of individual fatty acids to specific fetal tissues.     

Effects of different quantities of fat on serum and liver lipids, phospholipid class distribution and fatty acid composition in alcohol-treated rats

The present study investigated the quantitative effect of dietary fats and ingestion of alcohol on serum and liver lipids, fatty acid bound to phospholipids and their class distribution of male Wistar rats. The rats in C (control) and A (alcohol) groups were fed a standard laboratory diet, HFC (high fat-control) and HFA (high fat-alcohol) groups were fed a high fat diet (standard diet supplemented with 20 g%w/w, sunflower oil: lard mixture 1: 1) for 6 wk. Alcohol-treated rats consumed alcohol at the rate of 9 g/kgbw/d (15-20% energy). Liver phospholipid (PL) content was decreased, and phospholipid/cholesterol liver molar ratio increased in the alcohol treated rats. The proportion of serum sphingophospholipid (Sph) was significantly lower and proportion of phosphatidylcholin (PC) significantly higher in serum PL in alcohol-treated rats. Phospholipid class distribution was unaffected by alcohol feeding in liver. Significantly lower levels of 16:1n-7 and higher levels of 20:5n-3 and 22:4n-6 in the serum PL were observed in the alcohol-treated rats. The groups on the HF diet increased levels of 20:4n-6, 22:4n-6 and total n-6, polyunsaturated fatty acid (PUFA) and decreased levels of 18:1n-9 and total monounsaturated fatty acids (MUFA)in both liver and serum PL, but n-3 fatty acid increased in serum PL and decreased in liver PL compared to groups on the standard diet. Alcohol fat interaction was evident in MUFA and PUFA/SFA in serum PL and n-6, MUFA, PUFA and polyunsaturated/saturated fatty acid ratios (PUFA/SFA) in liver PL. This study showed that the high fat intake in alcohol-treated rats increased levels of 20:4n-6, 22:4n-6 and 20:4/18:2 ratio, and decreased level of 18:1n-9 in liver and serum phospholipids.     

Influences of postnatal age and dietary nucleotides on plasma fatty acids in the weanling rat.

Dietary nucleotides seem to play a number of physiologic roles during early life. They are improved in the maintenance of the immune system, intestinal maturation, and lipid metabolism. Nucleotides affect the conversion of essential fatty acids into their long-chain polyunsaturated (PUFA) derivatives in both preterm and at-term newborn infants. This work examines the effect of postnatal age and dietary nucleotides on the fatty acid composition of total plasma lipids and lipid fractions in the rat. Weanling rats (21 days old) were divided into three groups. The first group was killed, and the other two groups were fed a standard semipurified diet, and the same diet supplemented with 250 mg each of CMP, UMP, AMP, GMP, and IMP per 100 g of diet for 4 weeks. Advancing postnatal age led to an increase of total plasma fatty acids, especially saturated, and PUFA of the n-6 series, whereas PUFA of the n-3 series decreased. The fatty acid profile of plasma phospholipids (PL) exhibited minor changes, although there was a tendency to show lower levels of saturates and PUFA of the n-3 series and increased levels of PUFA of the n-6 series. Cholesteryl esters showed a response similar to that of PL, although the increase in arachidonic acid (20:4n-6) was significant. For triglycerides, linoleic acid (18:2n-6) and monounsaturates increased their levels, whereas saturates decreased. Dietary nucleotides mediated a significant increase in total plasma fatty acids, namely monounsaturated fatty acids and PUFA of both n-6 and n-3 series as compared with the control group. The relative fatty acid composition of PL and cholesteryl esters was mostly unaffected.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dietary fatty acid composition in pregnancy alters neurite membrane fatty acids and dopamine in newborn rat brain

The importance of maternal dietary fatty acids on arachidonic acid [AA; 20:4(n-6)] and docosahexaenoic acid [DHA; 22:6(n-3)] in fetal brain nerve growth cone membranes and monoaminergic neurotransmitters was investigated. Rats were fed purified diets containing 20 g/100 g safflower oil with 74.3% 18:2(n-6), 0.2% 18:3(n-3), soybean oil with 55.4% 18:2(n-6), 7.7% 18:3(n-3) or high fish oil with 24.6% 22:6(n-3) through gestation. Tissue for rats within a litter were pooled at birth, brain growth cone membranes prepared and phosphatidylcholine (PC), phosphatidylserine (PS), phosphatidylethanolamine (PE) and phosphatidylinositol (PI) fatty acids quantified by gas-liquid chromatography. Dopamine, serotonin, and the metabolites 3,4-dihydroxyphenylacetic acid and homovanillic acid, and 5-hydroxyindolacetic acid were quantified by HPLC. Growth cone membranes from offspring of rats fed safflower oil had significantly lower, and offspring of rats fed high 22:6(n-3) fish oil had significantly higher 22:6(n-3) in PE, PS and PI than the soybean oil group. The growth cone membrane PC, PE and PS 20:4(n-6) was significantly lower in the fish oil than in the soybean or safflower oil groups. Serotonin concentration was significantly higher in brain of offspring in the safflower oil compared with the soybean oil group. The newborn brain dopamine was inversely related to PE DHA and PS DHA (P < 0.001), but positively related to PC AA (P < 0.05). These studies show that maternal dietary fatty acids may alter fetal brain growth cone (n-6) and (n-3) fatty acids, and neurotransmitters involved in neurite extension, target finding and synaptogenesis. The functional importance, however, is not known at this time.     

Dietary long-chain polyunsaturated fatty acids from different sources affect fat and fatty acid excretions in rats.

Several sources of long-chain polyunsaturated fatty acids (LCP) have been evaluated for infant-formula supplementation. These sources differ in their chemical structure [triglyceride (TG) or phospholipid (PL)], arrangement of fatty acids on the TG or PL backbone, fatty acid composition and presence of other lipid components. All of these characteristics influence fat digestion, may affect fat and fatty acid absorption, and hence, LCP bioavailability and metabolism in infancy. The main objective of this work was to establish the influence of different dietary LCP sources on overall fat and LCP absorption in early life. We compared fat and fatty acid excretions at weaning in rats fed control diets or diets supplemented with LCP as TG or PL. Two separate experiments were conducted. In Experiment 1, weanling rats were fed for 3 wk a control diet (C1), a diet with TG from tuna and fungal oils (TF-TG) or a diet with PL from pig brain concentrate (PB-PL). In Experiment 2, weanling rats were fed for 3 wk a control diet (C2), a diet containing egg-TG (EG-TG) or a diet containing egg-PL (EG-PL). Fat, mineral and saturated fatty acid excretions in feces were higher in rats fed PB-PL compared with those fed TF-TG diet. In Experiment 2, groups did not differ in fat and mineral excretions. However, the EG-PL group had lower fecal excretions of saturated fatty acids than the C2 and EG-TG groups. The 16:1(n-7), 18:1(n-9), 18:2(n-6) and 22:6(n-3) levels in feces were higher in the EG-TG group than in the EG-PL group. In summary, total fat and LCP excretions differed among rats fed diets supplemented with LCP from different sources.     

Black soybean extract reduces fatty acid contents in subcutaneous,but not in visceral adipose triglyceride in high-fat fed rats

Abstract

It is known that black soybean (BS) extract, rich in polyphenols, has beneficial effects against obesity, inflammation and insulin resistance. However, detailed effects of BS on lipid metabolism have not been documented well. In the present study, we compared fatty acid composition in visceral and subcutaneous adipose tissues of high-fat fed (HFF) rats and BS administered HFF rats. Black soybean administration for 6 weeks influenced neither body nor adipose tissue weights, blood glucose, plasma insulin levels, or insulin sensitivity. However, BS reduced several saturated (C14:0 and C16:0), monounsaturated (C14:1n-5 and C18:1n-9) and n-6 polyunsaturated (C18:2n-6, C20:3n-6, C20:4n-6 and C22:4n-6) fatty acid contents in subcutaneous fat without any change in n-3 polyunsaturated fatty acid contents. No such effect was observed in fatty acid composition in visceral fat. Long-chain fatty acids are involved in regulation of inflammation. Therefore, those reduced fatty acids may be linked to the effects on suppressing inflammation.     

Brain synaptosomal, liver, plasma, and red blood cell lipids in piglets fed exclusively on a vegetable-oil-containing formula with and without fish-oil supplements

Clinical studies showed that a decrease in red blood cell 22:6n-3 caused by feeding infants formula (F) can be prevented by supplementation with fish oil (F + O). It is not known whether fish-oil supplementation is able to support normal accretion of fatty acids with greater than or equal to 20 carbons (LCPs) in the brain. Therefore piglets were fed exclusively F + O, F, or sow milk (SM) for 15 d and their liver and brain synaptosomal fatty acids were determined. Feeding F + O corrected the low n-3 LCP in the liver phospholipid (PL) and synaptosomal phosphatidylethanolamine (PE) of piglets fed F compared with SM. An apparent compensatory increase in n-6 LCPs in liver PL and synaptosomal PE of piglets fed F compared with SM was suppressed by feeding F + O. F + O also reduced the ratio of plasma PL 20:4n-6 to 20:5n-3, important for eicosanoid metabolism. Supplementation of F with n-3 LCPs as fish oil, without n-6 LCPs, at levels giving normal brain n-3 LCP, may alter n-6 LCP accretion.     

The effect of eicosapentaenoic acid on rat lymphocyte proliferation depends upon its position in dietary triacylglycerols

Animal and human studies have shown that greatly increasing the amount of fish oil [rich in long-chain (n-3) PUFA] in the diet can decrease lymphocyte functions. The effects of a more modest provision of long-chain (n-3) PUFA and whether eicosapentaenoic acid (20:5) and docosahexaenoic acid (22:6) have the same effects as one another are unclear. Whether the position of 20:5 or 22:6 in dietary triacylglycerols (TAG) influences their incorporation into immune cells and their subsequent functional effects is not known. In this study, male weanling rats were fed for 6 wk one of 9 diets that contained 178 g lipid/kg and that differed in the type of (n-3) PUFA and in the position of these in dietary TAG. The control diet contained 4.4 g alpha-linolenic acid (18:3)/100 g total fatty acids. In the other diets, 20:5 or 22:6 replaced a portion (50 or 100%) of 18:3, and were in the sn-2 or the sn-1(3) position of dietary TAG. There were significant dose-dependent increases in the proportion of 20:5 or 22:6 in spleen mononuclear cell phospholipids when 20:5 or 22:6 was fed. These increases were at the expense of arachidonic acid and were largely independent of the position of 20:5 or 22:6 in dietary TAG. Spleen lymphocyte proliferation increased dose dependently when 20:5 was fed in the sn-1(3) position of dietary TAG. There were no significant differences in interleukin-2, interferon-gamma or interleukin-10 production among spleen cells from rats fed the different diets. Prostaglandin E(2) production by spleen mononuclear cells was decreased by inclusion of either 20:5 or 22:6 in the diet in the sn-1(3) position. Thus, incorporation of 20:5 or 22:6 into spleen mononuclear cell phospholipids is not influenced by the position in dietary TAG. However, the pattern of incorporation may be influenced, and there are some differential functional effects of the position of long-chain (n-3) PUFA in dietary TAG. A moderate increase in the intake of 20:5 at the sn-1(3) position of dietary TAG increases lymphocyte proliferation.