Acid Composition In Rats Research Articles

Impact of n-3 Docosapentaenoic Acid Supplementation on Fatty Acid Composition in Rat Differs Depending upon Tissues and Is Influenced by the Presence of Dairy Lipids in the Diet.

The n-3 docosapentaenoic acid (n-3 DPA) could be a novel source of n-3 long-chain polyunsaturated fatty acids (LCPUFA) with beneficial physiological effects. Following the supplementation of 0.5% purified n-3 DPA for 3 weeks from weaning, the n-3 DPA content increased in one-half of the 18 studied tissues (from +50% to +110%, p < 0.05) and mostly affected the spleen, lung, heart, liver, and bone marrow. The n-3 DPA was slightly converted into DHA (+20% in affected tissues, p < 0.05) and mostly retroconverted into EPA (35-46% of n-3 DPA intake in liver and kidney) showing an increased content of these LCPUFA in specific tissues. The partial incorporation of dairy lipids in the diet for 6 weeks increased overall n-3 PUFA status and brain DHA status. Furthermore, the n-3 DPA supplementation and dairy lipids had an additive effect on the increase of n-3 PUFA tissue contents. Moreover, n-3 DPA supplementation decreased plasma cholesterol.

The impact of dietary feta cheese and butter on serum lipid profile and fatty acid composition in rat

PurposeCardiovascular diseases (CVDs) are the most common causes of death worldwide. Diets rich in saturated and trans-fatty acids are nutritional risk factors that foster the development of CVDs. The aim of this experimental study was to investigate the effects of dietary feta cheese and butter on serum lipid profile and fatty acid composition.Design/methodology/approachIn all, 24 Wistar rats (eight weeks old) were fed with balanced high fat diets (24 per cent fat) including canola (control group) and either cheese or butter (experimental groups) for eight weeks. At the end of the experiment, body weights were determined, and the amount of food intake was calculated. Blood samples were collected at the beginning and at the end of the experiment, and lipid profile including total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C) and triglyceride as well as serum fatty acid composition were determined.FindingsConsumption of the butter-based diet resulted in a significant increase in serum triglycerides (p < 0.05), whereas no substantial changes were observed in rats that received a cheese-based diet. The butter-based diet significantly increased serum total cholesterol and LDL-C (p < 0.05), whereas remarkably reduced HDL-C level. In contrast, cheese-based diet resulted in a magnificent increase in HDL-C and a significant decrease in LDL-C/HDL-C ratio (p < 0.05). Serum saturated fatty acids increased and polyunsaturated fatty acids decreased by the consumption of butter, whereas the intake of cheese caused relatively minor alterations in serum fatty acid composition.Originality/valueButter lowered HDL-C and increased LDL-C, whereas cheese strongly enhanced HDL-C. Therefore, it can be concluded that cheese is a beneficially healthier dairy product than butter.

Maternal high fat diet deficient in vitamin B12 influences long chain polyunsaturated fatty acid composition in rats

Objective: In India, there is a rise in non-communicable diseases due to diets deficient in vitamin B12, low in docosahexaenoic acid (DHA) and increased consumption of westernized diet. The present study aims to examine the effect of maternal high fat diet (HFD) in absence of vitamin B12 on pregnancy outcome and tissue fatty acid composition in dams.Methods: Pregnant Wistar rats were assigned to following diets: Control (C), HFD, High fat diet supplemented with omega-3 fatty acids (HFDO), 4) High fat diet deficient in vitamin B12 (HFBD), High fat deficient in vitamin B12 supplemented with omega-3 fatty acids (HFBDO).Results: There was no effect on pregnancy outcome as a consequence of different dietary treatments. The levels of DHA in HFBD group were lower (p < 0.05 for both) in placenta as compared to both control and HFD groups, which were improved by omega-3 fatty acid supplementation.Conclusion: This data suggests that maternal HFD (using dairy fat) did not adversely affect pregnancy outcome. However, maternal HFBD reduced levels of placental DHA. This may have implications for reduced fetal brain growth and development.

Chlorogenic acid from honeysuckle improves hepatic lipid dysregulation and modulates hepatic fatty acid composition in rats with chronic endotoxin infusion.

Chlorogenic acid as a natural hydroxycinnamic acid has protective effect for liver. Endotoxin induced metabolic disorder, such as lipid dysregulation and hyperlipidemia. In this study, we investigated the effect of chlorogenic acid in rats with chronic endotoxin infusion. The Sprague-Dawley rats with lipid metabolic disorder (LD group) were intraperitoneally injected endotoxin. And the rats of chlorogenic acid-LD group were daily received chlorogenic acid by intragastric administration. In chlorogenic acid-LD group, the area of visceral adipocyte was decreased and liver injury was ameliorated, as compared to LD group. In chlorogenic acid-LD group, serum triglycerides, free fatty acids, hepatic triglycerides and cholesterol were decreased, the proportion of C20:1, C24:1 and C18:3n-6, Δ9-18 and Δ6-desaturase activity index in the liver were decreased, and the proportion of C18:3n-3 acid was increased, compared to the LD group. Moreover, levels of phosphorylated AMP-activated protein kinase, carnitine palmitoyltransferase-I, and fatty acid β-oxidation were increased in chlorogenic acid-LD group compared to LD rats, whereas levels of fatty acid synthase and acetyl-CoA carboxylase were decreased. These findings demonstrate that chlorogenic acid effectively improves hepatic lipid dysregulation in rats by regulating fatty acid metabolism enzymes, stimulating AMP-activated protein kinase activation, and modulating levels of hepatic fatty acids.

Endocrine Disruptor DDE Associated with a High-Fat Diet Enhances the Impairment of Liver Fatty Acid Composition in Rats.

The banned pesticide dichlorodiphenyltrichloroethane (DDT) and its main metabolite, p,p'-dichlorodiphenyldichloroethylene (DDE), are commonly found in the food chain and in all tissues of living organisms. DDE is associated with metabolic diseases acting as an endocrine disruptor and more recently with the obesity pandemic. This study focuses on using fatty acid analysis to relate DDE exposure and metabolic dysfunction: liver and adipose tissue (visceral and subcutaneous) composition from male Wistar rats fed a standard (STD) or high-fat (HF) diet versus the addition of DDE in water. DDE exposure increased liver levels of palmitic, stearic, oleic, trans fatty, and linoleic acids having altered the n6 and n3 pathways leading to high concentrations of arachidonic acid and DHA (C22:6 n3). The results of this study confirm the close relationship between this pesticide metabolite and hepatic lipid dysfunction, underscoring its role as an emerging target for the prevention and therapy of nonalcoholic fatty liver disease (NAFLD).

Effects of L-Carnitine Supplementation on Growth Performance and Fatty Acid Proportion in Epididymal Adipose Tissue of Rats Fed Diets containing Fat from Different Sources

Effects of L-Carnitine Supplementation on Growth Performance and Fatty Acid Proportion in Epididymal Adipose Tissue of Rats Fed Diets containing Fat from Different Sources Two experiments were conducted to evaluate the effects of Lcarnitine supplementation on growth performance and epididymal adipose tissue fatty acid composition in rats fed diets containing different sources of fat. In the first study, rats were assigned to four groups receiving dietary treatments to evaluate the effects of supplementation with L-carnitine 0 ppm or L-carnitine 50 ppm in combination with two types of dietary fat: 100% soybean oil and a mixture of 50% soybean oil and 50% beef tallow. In the second study, the animals walked 2 h/day at a speed of 840 m/h. No significant differences were observed in the growth test results of each study. In experiment 1, the total saturated fatty acid (SFA) proportion was significantly higher in the L-carnitine 0 ppm 50% soybean oil and 50% beef tallow group than in the other groups. Dietary Lcarnitine suppressed the increase in the SFA proportion observed upon beef tallow consumption. In experiment 2, Lcarnitine decreased the SFA proportion and increased the monounsaturated fatty acid (MUFA) proportion. No interaction between the ingested fat type and L-carnitine supplementation on the proportions of individual fatty acids was observed, but Lcarnitine supplementation increased the C16:1 proportion and decreased the C18:0 proportion as a main effect in experiment 2. In conclusion, the current results suggest that dietary Lcarnitine decreased the SFA proportion in accordance with C18:0 utilization for energy production in walking rats.

Overfeeding of saturated fat and fructose induces alterations of hepatic fatty acid composition in rats (1142.10)

Fatty acids (FAs) are essential components of lipids and exhibits important biological functions. The analysis of FAs profiles in tissues has become increasingly important as end points in understanding the roles of FAs in physiological or pathological processes. This study aimed to describe the changes in fatty acid composition of the liver lipids caused by excessive consumption of high saturated fat diet associated with fructose in Wistar rats. Rats were fed ad libitum with chow (3 Kcal/g; 2.3% soybean oil) or high‐fat diet (5.5 Kcal/g; 30% lard and 4% soybean oil) associated with fructose (100mg/mL) for 12 weeks. The lipids of liver homogenates were extracted with chloroform‐MeOH and the fatty acids methyl esters were analyzed by gas‐chromatography. Fatty acid composition of the liver was found to shift from a pattern dominated by saturated (SFA, C16:0), monounsaturated (MUFA, 18:1 n‐9) and polyunsaturated FA (PUFA, C18:2 n‐6). Oleic acid (C18:1 n‐9) increased (approximately 36%, p=0.0001) whereas PUFA (C20:4 n‐6 and C22:6 n‐3) and SFA (18:0) decreased in the liver of animals fed with high saturated fat and fructose. This difference in the fatty acid profile in the liver is reflected in the increased MUFA/SFA ratio. The data indicated that the overfeeding of high saturated fat and fructose diets alter the hepatic fatty acid composition and the oleic acid is greatly accumulated in the liver.Grant Funding Source: FAPESP ‐ 2012/11050‐6

Dietary fatty acids modulate liver mitochondrial cardiolipin content and its fatty acid composition in rats with non alcoholic fatty liver disease

No data are reported on changes in mitochondrial membrane phospholipids in non-alcoholic fatty liver disease. We determined the content of mitochondrial membrane phospholipids from rats with non alcoholic liver steatosis, with a particular attention for cardiolipin (CL) content and its fatty acid composition, and their relation with the activity of the mitochondrial respiratory chain complexes. Different dietary fatty acid patterns leading to steatosis were explored. With high-fat diet, moderate macrosteatosis was observed and the liver mitochondrial phospholipid class distribution and CL fatty acids composition were modified. Indeed, both CL content and its C18:2n-6 content were increased with liver steatosis. Moreover, mitochondrial ATP synthase activity was positively correlated to the total CL content in liver phospholipid and to CL C18:2n-6 content while other complexes activity were negatively correlated to total CL content and/or CL C18:2n-6 content of liver mitochondria. The lard-rich diet increased liver CL synthase gene expression while the fish oil-rich diet increased the (n-3) polyunsaturated fatty acids content in CL. Thus, the diet may be a significant determinant of both the phospholipid class content and the fatty acid composition of liver mitochondrial membrane, and the activities of some of the respiratory chain complex enzymes may be influenced by dietary lipid amount in particular via modification of the CL content and fatty acid composition in phospholipid.

Brain lipids in rats fed a diet supplemented with hen eggs of modified lipid content

The aim of this study was to research the impact of a diet supplemented with egg yolks of modified content, having in mind the type of fat added to the laying hens diet, on the brain lipids and their fatty acid composition in rats. During four weeks of the experiment, 64 Wistar rats, divided into four groups of 16 animals each (eight animals of both sexes), were fed the commercial rat feed (group C), or the feed that contained 70% of the commercial rat feed and 30% of freshly boiled yolks from the eggs originating from laying hens fed with 3% fish oil (group F), 3% palm olein (group P) or 3% lard (group L). Concentration and content of total lipids and total cholesterol, as well as the fatty-acid composition of the total brain lipids were determined in the lipid extracts of the rats brains. Under unfavourable conditions, which in our case could be high dietary intake of the total fat due to egg yolk addition, the amount of total fat in the brain tissue or the mass of the organ itself can be changed. Applied dietary treatments could also influence the level of de novo synthesis of total cholesterol in the rat brain. High dietary fat intake, as well as the fat quality regarding its fatty acid composition, appear to be able to significantly influence the fatty acid profile of the total brain lipids in adult rats, whereas the level and quality of the changes also depend on sex.

Dietary (n-6 : n-3) Fatty Acids Alter Plasma and Tissue Fatty Acid Composition in Pregnant Sprague Dawley Rats

The objective of this paper is to study the effects of varying dietary levels of n-6 : n-3 fatty acid ratio on plasma and tissue fatty acid composition in rat. The treatment groups included control rats fed chow diet only, rats fed 50% soybean oil (SBO): 50% cod liver oil (CLO) (1 : 1), 84% SBO: 16% CLO (6 : 1), 96% SBO: 4% CLO (30 : 1). Blood samples were taken at day 15 of pregnancy, and the plasma and tissue were analyzed for fatty acid profile. The n-3 PUFA in plasma of Diet 1 : 1 group was significantly higher than the other diet groups, while the total n-6 PUFA in plasma was significantly higher in Diet 30 : 1 group as compared to the control and Diet 1 : 1 groups. The Diet 1 : 1 group showed significantly greater percentages of total n-3 PUFA and docosahexaenoic acid in adipose and liver tissue, and this clearly reflected the contribution of n-3 fatty acids from CLO. The total n-6 PUFA, linoleic acid, and arachidonic acid were significantly difference in Diet 30 : 1 as compared to Diet 1 : 1 and control group. These results demonstrated that the dietary ratio of n-6 : n-3 fatty acid ratio significantly affected plasma and tissue fatty acids profile in pregnant rat.

Angiotensin (1-7)/Mas receptor axis activation ameliorates the changes in fatty acid composition in diabetic rats with nephropathy.

Diabetes mellitus is often associated with altered fatty acids composition. This study was designed to investigate the role of angiotensin (Ang) (1-7)/Mas receptor in improving fatty acids composition in streptozotocin (STZ)-induced diabetic nephropathy (DN) in rats. Rats treated with STZ (50 mg/kg, i.p. once) developed DN after 8 weeks. Fatty acid composition was estimated in renal cortical tissue by gas chromatography. Treatment with Ang (1-7), A-779, and Ang (1-7) plus A-779 was given from week 4 to week 8. Diabetic rats exhibited a significant increase in levels of saturated fatty acids and a significant decrease in levels of polyunsaturated fatty acids (PUFAs). Treatment with Ang (1-7) significantly attenuated these diabetes-induced changes. In diabetic rats, prior administration of A-779 significantly attenuated the increase in PUFAs produced by Ang (1-7); however, for saturated fatty acids, A-779 significantly blocked the decrease in palmitic acid only. Our study, for the first time, documented that endogenous Ang (1-7) modulates fatty acid composition in rats. Further, treatment with Ang (1-7) significantly attenuated diabetes-induced changes in fatty acids composition. This may be an additional mechanism implying the renoprotective role of Ang (1-7) in diabetic rats.

Short Chain Saturated Fatty Acids Decrease Circulating Cholesterol and Increase Tissue PUFA Content in the Rat

This study investigates the effect of various dietary saturated fatty acid (SFA) profiles on plasma lipid parameters and tissue fatty acid composition in rats. The experiment was designed to monitor polyunsaturated fatty acids (PUFA) levels, while examining different amounts and types of SFA. Four isocaloric diets were prepared, containing 10-11mol% of fatty acids (FA) as linoleic acid (LNA) and 2.5mol% as α-linolenic acid (ALA), leading to an identical and well-balanced LNA/ALA ratio. The initial rapeseed oil/corn oil mixture providing ALA and LNA was enriched with olive oil to prepare the olive oil diet. The butterfat diet was supplemented with butterfat, containing short-chain SFA (C4:0-C10:0, 17mol% of FA), lauric acid (C12:0, 3.2mol%), myristic acid (C14:0, 10.5mol%) and palmitic acid (C16:0, 14.5mol%). The saturates diet was supplemented with trilaurin, trimyristin and tripalmitin to obtain the same level of lauric, myristic and palmitic acids as the butterfat diet, without the short-chain SFA. The trimyristin diet was enriched with trimyristin only. The results showed that the butterfat diet contributed to specific effects, compared to the olive oil diet and the saturates and trimyristin diets: a decrease in plasma total, LDL- and HDL-cholesterol, higher tissue storage of ALA and LNA, and a higher level of (n-3) highly unsaturated fatty acids in some tissues. This study supports the hypothesis that in diets with identical well-balanced LNA/ALA ratios, short chain SFA may decrease circulating cholesterol and increase tissue polyunsaturated fatty acid content in the rat.

Influence of high-fat diet from differential dietary sources on bone mineral density, bone strength, and bone fatty acid composition in rats

Previous studies have suggested that high-fat diets adversely affect bone development. However, these studies included other dietary manipulations, including low calcium, folic acid, and fibre, and (or) high sucrose or cholesterol, and did not directly compare several common sources of dietary fat. Thus, the overall objective of this study was to investigate the effect of high-fat diets that differ in fat quality, representing diets high in saturated fatty acids (SFA), n-3 polyunsaturated fatty acids (PUFA), or n-6 PUFA, on femur bone mineral density (BMD), strength, and fatty acid composition. Forty-day-old male Sprague-Dawley rats were maintained for 65days on high-fat diets (20% by weight), containing coconut oil (SFA; n = 10), flaxseed oil (n-3 PUFA; n = 10), or safflower oil (n-6 PUFA; n = 11). Chow-fed rats (n = 10), at 105days of age, were included to represent animals on a control diet. Rats fed high-fat diets had higher body weights than the chow-fed rats (p< 0.001). Among all high-fat groups, there were no differences in femur BMD (p> 0.05) or biomechanical strength properties (p> 0.05). Femurs of groups fed either the high n-3 or high n-6 PUFA diets were stronger (as measured by peak load) than those of the chow-fed group, after adjustment for significant differences in body weight (p = 0.001). As expected, the femur fatty acid profile reflected the fatty acid composition of the diet consumed. These results suggest that high-fat diets, containing high levels of PUFA in the form of flaxseed or safflower oil, have a positive effect on bone strength when fed to male rats 6 to 15weeks of age.

Conjugated linoleic acid decreased serum triacyloglycerol and changed fatty acid composition in rat’s liver

Conjugated linoleic acid decreased serum triacyloglycerol and changed fatty acid composition in rat’s liver

Effects of the ω‐6:ω‐3 Fatty Acid Ratio of Fat Emulsions on the Fatty Acid Composition in Cell Membranes and the Anti‐Inflammatory Action

This study investigated the effects of parenterally administered fish oil (FO) on the fatty acid composition in rats to determine the optimal omega-6:omega-3 polyunsaturated fatty acid (PUFA) ratio of fat emulsions to achieve an anti-inflammatory effect. Male Sprague-Dawley rats were infused a parenteral nutrition (PN) solution containing fat emulsions with different omega-6:omega-3 PUFA ratios. The fatty acid content of phospholipids in the membranes of splenocytes was analyzed by gas chromatography (experiment 1). In addition, the amounts of leukotriene (LT) B(4) and LTB(5) released from peritoneal polymorphonuclear leukocytes (PMNs) were measured by high-performance liquid chromatography (experiment 2). In experiment 1, after infusion of the fat emulsion containing FO, the omega-3 PUFA content in cell membranes rose to 70% of the peak value on day 1 and nearly reached a plateau on day 3. The highest ratio of eicosapentaenoic acid (EPA) to arachidonic acid (AA) was achieved by administering a PN solution with the smallest omega-6:omega-3 PUFA ratio. In experiment 2, a larger amount of LTB(5) was released from Ca-ionophore-stimulated PMNs taken from rats given a larger quantity of FO. The ratio of LTB(5):LTB(4) released from PMNs correlated positively with the EPA:AA ratio in the membranous phospholipid and in serum. The omega-3 PUFAs were readily incorporated into the cell membrane within 3 days of infusion with the fat emulsion. The EPA:AA ratio in membranous phospholipid in PMNs was positively correlated with the LTB(5):LTB(4) production ratio and was a good indicator of anti-inflammatory effects.

Effect of the Fatty Acid Composition of Oil in a High-Cholesterol Diet on the Serum Lipid Concentration and Hepatic Fatty Acid Composition in Rats

Effect of the Fatty Acid Composition of Oil in a High-Cholesterol Diet on the Serum Lipid Concentration and Hepatic Fatty Acid Composition in Rats

Adiponectin is associated with serum and adipose tissue fatty acid composition in rats

The objective of the present work is to analyse the relationships between changes in adiponectin and fatty acid composition in serum and adipose tissue in rats. Samples from serum and different adipose depots (periovarian, mesenteric and subcutaneous) were obtained from ageing rats (14- and 20-month-old) to determine fatty acid composition (gasliquid chromatography). In serum, insulin (radioimmunoassay) and adiponectin levels (enzyme-linked immunosorbent assay) were also measured, while adiponectin gene expression was analysed (real time-qPCR) in all fat depots. There were significant age-related reductions in adipose tissue saturated (SFA) and trans fatty acids and increases in monounsaturated fatty acids in parallel with diminished adiponectin expression in periovarian and mesenteric adipose tissue (p<0.05). Age-independent negative correlations were found between adiponectin gene expression in mesenteric adipose tissue and C12:0, C14:0 and C18:2 trans fatty acids (p<0.05). There was a positive association between serum adiponectin and adipose tissue oleic acid, while palmitoleic acid was negatively associated with adiponectin expression and positively correlated with insulin concentration. For the first time, positive relationships are reported between the proportion of n-6 polyunsaturated fatty acids (PUFA) in adipose tissue and adiponectin concentration and expression. In summary, adiponectin expression and serum levels are associated with fatty acid composition, with SFA, trans and palmitoleic fatty acids appearing as negative markers for adiponectin, and oleic acid and n-6 PUFA as positive ones. In addition, most associations were found in the visceral depots, highlighting the importance of visceral fat in the metabolic status.

Chronic risperidone treatment preferentially increases rat erythrocyte and prefrontal cortex omega-3 fatty acid composition: Evidence for augmented biosynthesis

Prior clinical studies suggest that chronic treatment with atypical antipsychotic medications increase erythrocyte and postmortem prefrontal cortex (PFC) omega-3 fatty acid composition in patients with schizophrenia (SZ). However, because human tissue phospholipid omega-3 fatty acid composition is potentially influenced by multiple extraneous variables, definitive evaluation of this putative mechanism of action requires an animal model. In the present study, we determined the effects of chronic treatment with the atypical antipsychotic risperidone (RISP, 3.0 mg/kg/d) on erythrocyte and PFC omega-3 fatty acid composition in rats maintained on a diet with or without the dietary omega-3 fatty acid precursor, alpha-linolenic acid (ALA, 18:3 n-3). Chronic RISP treatment resulted in therapeutically-relevant plasma RISP and 9-OH-RISP concentrations (18 ± 2.6 ng/ml), and significantly increased erythrocyte docosahexaenoic acid (DHA, 22:6 n-3, + 22%, p = 0.0003) and docosapentaenoic acid (22:5 n-3, + 18%, p = 0.01) composition, and increased PFC DHA composition (+ 7%, p = 0.03) in rats maintained on the ALA+ diet. In contrast, chronic RISP did not alter erythrocyte or PFC omega-3 fatty acid composition in rats maintained on the ALA− diet. Chronic RISP treatment did not alter erythrocyte or PFC arachidonic acid (AA, 20:4 n-6) composition. These data suggest that chronic RISP treatment significantly augments ALA−DHA biosynthesis, and preferentially increases peripheral and central membrane omega-3 fatty acid composition. Augmented omega-3 fatty acid biosynthesis and membrane composition represents a novel mechanism of action that may contribute in part to the efficacy of RISP in the treatment of SZ.

High intakes of fructose are associated with alterations in liver fatty acid composition in rats

Background: Diets high in fructose may result in abnormalities in glucose and lipid metabolism.Purpose: To investigate the effects of a high‐fructose diet on liver fatty acid composition.Methods: Male Sprague‐Dawley rats were divided into two groups: a control group (n=5) receiving standard chow diet, and treatment group (n=7) receiving a diet containing 10% w/w lard and 60% w/w fructose for 20 weeks. Fatty acid profile of various lipid fractions in the liver of these animals was characterized.Results: Total liver lipids including cholesterol and triacyglycerol (TAG) were significantly higher in the treated group as compared to controls. The livers from treated animals had significantly lower levels of C16:0 and higher levels of C18:1 in the TAG fraction, and lower levels of C18:1c11, C18:2c9, C20:1c11, C20:1c13 along with higher levels of C16:1 and C18:1c9 in the free fatty acid fraction. The levels of C16:0, C18:2c9, C20:1c11, C20:1c13, C20:2c11 and C24:0 were significantly increased in the phosholipid fraction of the treated animals.Conclusions: High intakes of fructose change liver lipid composition and fatty acid profile in rats. TAG and phospholipid fractions seem to be affected more. These changes may lead to alterations in hepatocyte functions including lipid metabolism and may modify cardiovascular risk.

Artificial rearing with docosahexaenoic acid and n-6 docosapentaenoic acid alters rat tissue fatty acid composition

Docosahexaenoic acid (DHA; 22:6n-3) and n-6 docosapentaenoic acid (DPAn-6; 22:5n-6) are components of enriched animal feed and oil derived from Schizochytrium species microalgae. A one generation, artificial rearing model from day 2 after birth onward (AR) and a dam-reared control group (DAM) were used to examine DPAn-6 feeding on the fatty acid composition of various rat tissues at 15 weeks of age. Four AR diets were based on an n-3 fatty acid-deficient, 18:2n-6-based artificial milk with 22:6n-3 and/or 22:5n-6 added: AR-LA, AR-DHA, AR-DPAn-6, and AR-DHA+DPAn-6. The 22:6n-3 levels for the DAM, AR-DHA, and AR-DHA+DPAn-6 groups tended to be similar and higher than in the AR-LA and AR-DPAn-6 groups. The levels of 22:5n-6 tended to be higher only in the absence of dietary 22:6n-3. Adipose levels of 22:5n-6 was the only exception, as 22:5n-6 was significantly higher in AR-DHA+DPAn-6 than was observed in either the DAM or the AR-DHA group. There were no differences in 20:4n-6 levels within the tissues examined. In conclusion, 22:5n-6 replaces 22:6n-3 in the absence of 22:6n-3 only and does not appear to compete with 22:6n-3 in the presence of dietary 22:6n-3, suggesting that oils containing 22:5n-6 and 22:6n-3 may be a good dietary source of 22:6n-3.