Dietary Lipid Content Research Articles

EFFECT OF A COMBINATION OF OMEGA-3 AND ORAL TESTOSTERONE UNDECANOATE ON SERUM TESTOSTERONE LEVELS IN PATIENTS WITH TESTOSTERONE DEFICIENCY

Background and Objective Oral testosterone undecanoate (TU) is taken up by the intestinal lymphatic system. Thus, the dietary lipid content affects TU absorption. This study aimed to investigate the effect of combined omega-3 fatty acids (OMG3) and oral TU on serum testosterone levels in patients with testosterone deficiency (TD). Material and Methods Sixty consecutive patients with symptomatic TD and low serum total testosterone (TT) levels were enrolled and divided randomly into group 1, oral TU 80 mg twice daily for 30 days, and group 2, OMG3 and oral TU 80 mg twice daily for 30 days. Serum TT concentrations and male function scales were evaluated at baseline and 7 days and 1 month post-treatment. Dietary habits were investigated, and caloric and lipid intakes were measured during the treatment periods. Results The groups did not differ in terms of mean age, body mass index, comorbidities, initial serum TT concentrations, and IIEF/AMS scores. After 7 days and 1 month of treatment, serum TT concentrations were only significantly increased in group 2. The degree of increase in TT was higher in group 2 than in group 1 at 7 days and 1 month, although the difference was only significant at 1 month. Both groups exhibited significant improvements in IIEF and AMS scores at 1 month, with no significant inter-group difference. A diet diary study revealed that 23.3% and 20% of both groups did not eat breakfast and both groups consumed <12 g of lipids and <500 Kcals, without significance differences. Conclusion We observed a significant increase in serum TT concentration after 1 month of treatment with the combination of OMG3 and oral TU, compared to with oral TU monotherapy. Therefore, the combination of OMG3 and oral TU can be considered for the treatment of TD in Korean patients with irregular breakfast habits.

384 Metabolizable energy content of feeds: Errors that need attention

Abstract Feedlot performance is predicted reliably from DMI and diet NE. Tabular NE values in turn commonly are calculated from TDN either measured in digestion trials or predicted from nutrient compositions. When estimated from nutrient composition (NRBC, 2016), TDN values for feeds were related imprecisely (R2 = 0.83) to in vivo TDN values (NRC, 2000); deviations ranged from -29% to 162%. Traditionally, DE has been calculated as TDN percentage times 0.044, an assumed calorie content of carbohydrate (4.4 kcal/g). Surprisingly, this value is 5% greater than the heats of combustion of DM from isolated starch, cellulose, and glycogen (4.1788, 4.1810, and 4.1868 kcal/g; Blaxter, 1962; The Energy Metabolism of Ruminants). Being “carbohydrate-equivalent energy,” TDN includes the extra calories from lipid whereas urinary energy (UE) lost during catabolism of digested protein automatically is deducted. When determined calorimetrically, ME equals DE minus both gas energy (GasE) loss and UE. But when DE is being calculated from TDN, UE from digested CP already has been subtracted. Double deduction for UE underestimates ME content of high protein feeds. When DE is calculated from TDN, ME equals DE minus only GasE. Using data assembled by Galyean et al. (2016), multiple regression revealed that GasE was predicted more accurately from dietary NDF and lipid concentrations (GasE, % of DE = 4.87 + 0.131 x NDF - 0.331 x EE; R2 = 0.69) than from diet DE (R2 = 0.27). From this formula, GasE loss as a fraction of DE of feeds ranges from 5 to 15% except for isolated fats than have a negative value; non-additivity across feeds complicates formulation of least cost diets. Correcting discrepancies in calculating ME from TDN should improve reliability of predicting the cost of ME from various feeds and for quantifying feed requirements for maintenance and gain of cattle fed diverse diets.

Evaluation of Major Dietary Ingredients in Diverse Oats (Avena sativa L.) Germplasm

Oat (Avena sativa L.) is one of the world’s most important cereal crops, owing to its use as an important source of essential nutrients for both humans and animals. In the present study, the main nutritional components of 975 oat germplasm accessions were investigated. Crude fiber content ranged from 0.08 to 6.79%, with a mean of 2.14%, whereas total dietary fiber content ranged from 5.32 to 17.59%, with a mean of 11.01%, β-glucan content ranged from 1.02 to 6.33%, with a mean of 3.05%, and lipid content ranged from 1.41 to 8.72%, with a mean of 4.73%. Furthermore, most of the germplasm accessions exhibited 1-3% crude fiber content in the range of 1-3%, 9-12% total dietary fiber content, 2-4% β-glucan content, and 4-5% lipid content. Both the crude fiber and total dietary fiber contents were significantly but weakly correlated with β-glucan content, and the nutritional contents of germplasm accessions from different countries varied significantly. The highest mean crude fiber, total dietary fiber, β-glucan, and lipid contents were exhibited by the germplasm accessions collected from Canada, the UK, the Netherlands, and Turkey, respectively, and the accessions that exhibited the highest crude fiber (n=4), total dietary fiber (n=7), β-glucan content (n=5), and lipid (n=12) contents were identified. These findings provide valuable information for breeding programs aiming to improve the nutritional value of already existing high-yielding oat cultivars.

Protein and lipid requirements of three-spot cichlid Cichlasoma trimaculatum larvae.

Determination of the main nutritional requirements at different developmental stages is a prerequisite in the formulation of feeds for newly cultured fish species. In the present study, the lipid and protein requirements of larvae of a native Mexican fish, the three-spot cichlid Cichlasoma trimaculatum, were assessed using a two-factor experimental design that considered four protein (35, 40, 45, and 50%) and two lipid levels (16 and 22%) on growth, survival, and digestive enzyme activities. The best growth and feed efficiency results were obtained when larvae were fed diets including 45% protein and 22% lipids. Comprehensive evaluation of the profile of digestive enzymes using multivariate analysis also demonstrated significant differences in nutritional condition generated by varying inclusion of nutrients. Thus, an increase in protein led to an increase in alkaline protease activity and a reduction in leucine aminopeptidase activity, and the reduction of dietary lipid content led to a significant increase in lipase and trypsin enzymatic activities. Based on our results, C. trimaculatum larvae have a high capacity to hydrolyze both nutrients (protein and lipids) for the high digestive enzyme activities and increase their growth, particularly with a diet containing 45% protein and 22% lipids.

Signatures of Relaxed Selection in the CYP8B1 Gene of Birds and Mammals.

The CYP8B1 gene is known to catalyse reactions that determine the ratio of primary bile salts and the loss of this gene has recently been linked to lack of cholic acid in the bile of naked-mole rats, elephants and manatees using forward genomics approaches. We screened the CYP8B1 gene sequence of more than 200 species and test for relaxation of selection along each terminal branch. The need for retaining a functional copy of the CYP8B1 gene is established by the presence of a conserved open reading frame across most species screened in this study. Interestingly, the dietary switch from bovid to cetacean species is accompanied by an exceptional ten amino acid extension at the C-terminal end through a single base frame-shift deletion. We also verify that the coding frame disrupting mutations previously reported in the elephant are correct, are shared by extinct Elephantimorpha species and coincide with the dietary switch to herbivory. Relaxation of selection in the CYP8B1 gene of the wombat (Vombatus ursinus) also corresponds to drastic change in diet. In summary, our forward genomics-based screen of bird and mammal species identifies recurrent changes in the selection landscape of the CYP8B1 gene concomitant with a change in dietary lipid content.

Dietary fatty acid content influences the expression of genes involved in the lipid turnover and inflammation in mouse colon and spleen

BackgroundDietary interventions can improve gastrointestinal (GI) symptoms. We determined the effects of fatty acids (FAs) supplementation with medium- and long-chain saturated FAs on mouse GI motility and correlated them with the expression of genes for free FA receptors (FFAR)1–4, FA binding protein 4 (FABP4) and inflammation.MethodsForty-eight BalbC were assigned to: standard diet (STD), diet rich in medium-chain saturated FAs (COCO) and long-chain saturated FAs (HF) (7% by weight). Body weight (BW) and food intake (FI) were monitored for 8-weeks. GI motility was determined by fecal pellet output (FPO) and colon bead expulsion tests. FABP4 inhibitor, BMS309403 (1 mg/kg, ip) was injected to half of each group 2 days/week. mRNA expression of FABP4, (FFAR)1–4, and pro-inflammatory cytokines were measured in colonic and splenic tissues using real-time PCR.ResultsCOCO and HF decreased FI. COCO accelerated overall GI transit (p < 0.05). COCO increased the mRNA expression of FFAR2 (p < 0.001) and TNFα (p < 0.01); HF increased the expression of FABP4 and FABP4 (p < 0.05), and FFAR2 (p < 0.001) in the colon, and decreased FFAR1 and FABP4 (p < 0.001), TNFα (p < 0.01) and IL-1ß (p < 0.05) in splenic tissues. BMS309403 decreased the FI and delayed colonic transit in STD+BMS and COCO+BMS vs. STD (p < 0.05). HF+BMS increased colonic expression of FFAR3 (p < 0.01), TNFα (p < 0.01), IL-6 (p < 0.01), and reduced FFAR4 (p < 0.05); COCO + BMS decreased TNFα (p < 0.01).ConclusionDiversification in the dietary lipid content affected GI motility in mice and the expression of FFARs and pro-inflammatory cytokines in vivo.

The Dietary Lipid Content Affects the Tissue Gene Expression of Muscle Growth Biomarkers and the GH/IGF System of Pejerrey (Odontesthes bonariensis) Juveniles

Gene expression of growth hormone receptors (GHRs), insulin-like growth factors (IGFs), myostatin (MSTN) and myogenin (MyoG) was analyzed in juveniles pejerrey fed with graded levels of lipids (L): 6% (L6), 10% (L10), 25% (L25). After 14 weeks, no changes were found in liver GHR-I GHR-II and IGF-II mRNA levels whereas IGF-I decreased in L10 and L25. Muscle GHR-I gene expression increased in L25 whereas GHR-II, IGF-II and MyoG were higher in L6. IGF-I and MSTN expression was not affected by the different diets. Adipose IGF-I mRNA levels decreased in L10. Correlations between body weight and members of GH/IGF system in liver and skeletal muscle were found only in L10 group. Correlations found in L10 group between both liver and skeletal muscle GHR-I and IGF-I were lost in either L6 or L25 groups. Thus, fish fed with apparently unbalanced dietary lipid contents (6% and 25%) exhibit a compensatory regulation of systemic and local components of the GH/IGF axis. Furthermore, the marked inhibition of muscle MyoG gene expression in L25 might limit excessive lipid deposition and fish growth. Our data suggest that a dietary lipid contents of 10% would promote a particular adjustment of the endocrine and autocrine/paracrine GH/IGF system, stimulating body growth and perhaps muscle hyperplasia. On the other hand, a higher dietary lipid content would uncouple the GH/IGF system, reducing hepatic IGF-I, while slightly increasing hepatic GHR-I, probably to prompt lipolysis.

Effects of high-fat diet on muscle textural properties, antioxidant status and autophagy of Chinese soft-shelled turtle (Pelodiscus sinensis)

This research illustrates the effects of high-fat diet induced oxidative stress on muscle textural properties, oxidation status and autophagy of juvenile Chinese soft-shelled turtles (Pelodiscus sinensis) and explores the molecular regulatory mechanism. A total of 120 juvenile Chinese soft-shelled turtles with the average initial body weight of (38.60 ± 1.13) g were fed two diets that contained different lipid levels, 6.38% (normal diet, ND) and 13.89% (high-fat diet, HFD), for 8 weeks. The results indicated that: (1) the survival rate (SR) and feed conversion rate (FCR) were not significantly different (P > .05); the final body weight, weight gain rate (WGR), specific growth rate (SGR), and the hepatosomatic index (HIS) of groups that were fed with HFD were significantly higher than those fed with ND (P < .05). Moreover, the moisture and ash contents in the muscle and calipash were not significantly affected by the lipid level (P > .05), while the crude lipid content of the turtles increased, and the crude protein content decreased when the dietary lipid concentration increased (P < .05); (2) regarding the textural mechanical properties, no significant differences were observed in adhesiveness, cohesiveness and springiness (P > .05), but a significant decreases in hardness, gumminess and chewiness of muscle with HFD (P < .05); (3) the reactive oxygen species (ROS) and malondialdehyde (MDA) contents were increased in the HFD group (P < .05). It was significantly up-regulated the mRNA level of the signaling molecule Keap1 as well as down-regulated Nrf2 in the muscle (P < .05), meanwhile its downstream the activities of antioxidant enzymes of total superoxide dismutase (T-SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione-S-transferase (GST), glutathione reductase (GR) and the content of glutathione (GSH) and antioxidant gene expression were significantly decreased (P < .05); (4) the expressions of autophagy-related genes MAP1LC3A, MAP1LC3B, MAP1LC3C and ULK1 were significantly increased in the HFD group, while mTOR was significantly decreased as well as increased AMPK mRNA level (P < .05), and the transmission electron microscopy result showed that there were obviously more autophagosomes in muscle tissues of the HFD group than ND group. In summary, high-fat diet induced oxidative stress and autophagy in the juvenile Chinese soft-shelled turtles, which might be related to increased lipid content and ROS level by down-regulating the mRNA level of antioxidant enzymes, and inhibiting the Nrf2 and mTOR signaling pathways.

Effects of Dietary Carbohydrate and Lipid Concentrations on Growth Performance, Feed Utilization, Glucose, and Lipid Metabolism in Two Strains of Gibel Carp.

To test the hypothesis that effects of dietary carbohydrate and lipid concentrations on growth performance, feeding utilization, glucose and lipid metabolism in gibel carp A strain may be differ from F strain, these two strain of gibel carp were fed with one of three different isonitrogenous diets: HCLL (45% carbohydrate, 2% lipid), MCML (30% carbohydrate, 8% lipid), or LCHL (15% carbohydrate, 14% lipid). After 8 weeks, the HCLL-fed fish had the highest hepatosomatic index, hepatic crude lipid levels, and triglyceride levels and lipid retention efficiency. Enhanced lipogenesis and lipid uptake potential were observed in fish fed HCLL and MCML diets. Moreover, increases in glucose transport (glut2, P = 0.003) and glycolysis (gk, P = 0.012; 6pfk, P = 0.005) in livers of both strains were induced by the high-carbohydrate diet. Genotype-specific effect was identified on plasma lipid content. Plasma triglyceride levels were also greater in the F strain than in the A strain. Furthermore, the F strain had higher levels of fatty acid β-oxidation and glycolysis compared with the A strain. Nutrient retention was affected (P < 0.05) by the interaction between genotype and diet, implied dietary carbohydrate played a vital role in lipid accumulation in gibel carp. As dietary lipids increased, the F strain exhibited better feed utilization and a higher PRE than the A strain. However, the A strain had better growth performance. Overall, the F strain had better glucose uptake, glycolysis potential, and lipid utilization ability than the A strain.

Hepatic lipid metabolism and oxidative stress responses of grass carp (Ctenopharyngodon idella) fed diets of two different lipid levels against Aeromonas hydrophila infection

The present study was conducted to investigate the effect of Aeromonas hydrophila infection and different lipid level diets on the performance, hepatic lipid metabolism, and oxidative stress in grass carp (Ctenopharyngodon idella). To this end, grass carp (50.73 ± 3.17 g) were divided into 4 groups: control group, A. hydrophila group, high-fat diet group, high-fat diet + A. hydrophila group for 8 weeks. Compared with the control group, there was no significant difference in hepatic lipid content in the A. hydrophila group for 8 weeks, but it increased significantly in 4 weeks. The results showed that A. hydrophila infection and feeding with basal diet may have influenced hepatic lipid deposition in a time-dependent manner. The expression of lipid decomposition-related gene adipose triacylglyceride lipase (ATGL) and lipoprotein lipase (LPL) were reduced at 4 weeks, and lipid synthesis-related gene fatty acid synthase (FAS), acetyl-CoA carboxylase α (ACCα), and stearoyl-CoA desaturase (SCD) were suppressed at 8 weeks, which reduced the lipid metabolism of the liver. Compared with the high-fat diet group, the hepatic lipid content was significantly increased in high-fat diet + A. hydrophila group for 8 weeks, indicating that A. hydrophila infection aggravated hepatic lipid deposition induced by high-fat diet, the expression of ACCα and FAS were significantly up-regulated, and lipid decomposition-related genes (ATGL, LPL, CPT1) were not significantly changed, indicating that A. hydrophila infection of grass carp fed with a high-fat diet could increase liver lipid synthesis. Oil red O staining and the relative area of lipid droplets further support this finding. Moreover, in both groups, A. hydrophila infection enhanced serum aspartate transaminase (AST), which was found to cause liver injury. Total antioxidant capacity (T-AOC) was reduced and malondialdehyde (MDA) content was increased in the liver after infection of A. hydrophila in both basal diet and high-fat diet groups, indicating that A. hydrophila infection weakened the antioxidant defense ability of the liver, which led to the occurrence of oxidative stress and oxidative damage to the liver. Our results indicated that dysregulation of hepatic lipid metabolism and damage of the antioxidant system in grass carp could be caused by challenge to a certain dose of A. hydrophila, and hepatic lipid deposition induced by A. hydrophila infection was closely related to dietary lipid content.

Seasonality in Nutrient Contents of Edible Green Algae Ulva compressa and Ulva fasciata from Southeast Coast of India

Seasonal variations in the proximate (protein, carbohydrate, dietary fiber, ash, moisture, lipid, amino acid and fatty acid content), mineral composition (Na, K, Ca, Mg, Fe, Zn, C, Mn) and Heavy metals content (Cd, Pb, Hg and Ni) of Ulva compressa and Ulva fasciata were investigated for all four different seasons (Spring, North east monsoon, Summer and South west monsoon) during 2015 to 2016. Data were analyzed using one- and two-way ANOVA. Significant variations in the proximate constituents were found among seasons and species. Maximum proximate and mineral composition in U. compressa are protein, carbohydrate, ash content, moisture content and lipid in northeast monsoon, dietary fiber, amino acids content and mineral content in southwest monsoon, fatty acids content in spring. Heavy metals were not detected except lead. In U. fasciata, maximum proximate and mineral composition are protein, carbohydrate, moisture content, ash content in spring season, dietary fiber in summer season, lipid and total amino acids content in northeast monsoon, fatty acids contents and mineral content in southwest season. Heavy metals were not detected except lead. U. compressa has highest protein, carbohydrate, moisture content, amino acids and mineral content as compared to U. fasciata. U. fasciata has maximum dietary fiber, ash content, lipid content and fatty acids as compared to U. compressa. In general, Northeast monsoon showed the highest proximate and mineral composition in both the algae. The present study revealed that these two edible algae have higher proximate contents which can be more ideal for food consumption for humans and animals.

High-Lard and High-Cholesterol Diet, but not High-Lard Diet, Leads to Metabolic Disorders in a Modified Dyslipidemia Model.

BackgroundIn view of the increased global prevalence of cardiovascular and hepatic diseases, the diet lipid content and its relationship with the accumulation of fat in hepatocytes have been investigated as key factors in preventing these diseases.ObjectiveTo evaluate the metabolic effects of a high-lard diet supplemented or not with cholesterol on a modified dyslipidemia model.MethodsWe divided 24 adult male Wistar rats into three groups: standard diet (STD - 4% lipids), high-lard diet (HLD - 21% lard), and high-lard and high-cholesterol diet (HL/HCD - 20% lard, 1% cholesterol, 0.1% cholic acid). After six weeks of treatment, blood and liver were collected for biochemical (serum lipid profile and liver enzymes) and morphological analyses. Statistical analysis included one-way analysis of variance (ANOVA), followed by Tukey test for mean comparisons, and a 5% probability was considered statistically significant.ResultsAnimals fed HL/HCD showed increased total cholesterol, triacylglycerol, LDL-c, non-HDL-c, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) serum levels compared to those fed STD. In addition, the HL/HCD animals presented higher relative liver weight, with moderate macrovesicular hepatic steatosis and inflammatory infiltrate.ConclusionA high-fat diet with lard (20%) and cholesterol (1%) triggered dyslipidemia with severe liver damage in rats in a shorter experimental time than the previously reported models. The high-lard diet without supplementation of cholesterol led to body weight gain, but not to dyslipidemia.

Effects of dietary protein and lipid levels on growth, body composition and nutrient utilization of Channa striata

Very limited information is available on nutrient requirements of Channa striata, particularly during the grow-out stage. A study was carried out to study the requirement and utilization of protein and lipid by Channa striata growing from 31 g to ~ 200 g. Nine experimental diets with graded levels of dietary protein and lipid were formulated using practical ingredients. Increasing dietary crude protein content from 43.4% to 55.6% at 11% dietary lipid content resulted in increases of weight gain, amount of feed consumed, specific growth rate, and thermal-unit growth coefficient. The crude protein requirement of Channa striata was estimated by the saturation kinetics model to be 51.6% dry matter (DM) for growth and 52.1% DM for protein deposition. On the digestible protein basis, the requirement of Channa striata was estimated to be 47.2% DM for growth and 47.8% DM for protein deposition. Increasing lipid content in diets from 7.5% to 23.1% in this study resulted in linear decreases of fish growth and feed intake. Apparently Channa striata cannot tolerate high dietary lipid levels; lipid levels of >19% DM could negatively affect growth performance. It was also revealed that dietary lipids did not have a protein-sparing effect in Channa striata. Results from this study not only contribute to a better understanding of the nutrient requirement and utilization of Channa striata, but also would be helpful for the development of cost-effective sustainable practical feed formulations for this fish species.

Macrophage Recycling of Red Blood Cells and Iron Following Transfusion

Red blood cells (RBCs) destined for transfusion can be refrigerator stored for up to 42 days prior to transfusion. During this ex vivo storage period, RBCs are progressively damaged in a process that is termed the RBC storage lesion. The end result of this storage lesion is that with longer durations of storage prior to transfusion, an increased number of storage-damaged RBCs are cleared from the circulation via extravascular hemolysis. Studies in mice, dogs, and humans suggest that transfusion of older, stored RBCs, but not fresh RBCs, produce acute elevations in circulating markers of extravascular hemolysis (e.g., indirect bilirubin and transferrin saturation). Furthermore, hepcidin is induced in humans approximately 4-6 hours after transfusion and likely results in the return to baseline serum iron levels by 20-hours following transfusion. This is associated with a concomitant rise in serum ferritin levels, suggesting that hepcidin-induced degradation of ferroportin results in intracellular storage of iron within macrophages. Furthermore, the rate at which the macrophages release iron can be greater than the capacity of circulating transferrin to handle that iron, resulting in production of non-transferrin-bound iron. This pathogenic form of iron may be a cause of adverse effects in transfusion recipients. Indeed, in animal models, iron availability is associated with increased morbidity and mortality from infectious challenges with certain bacteria. A human study comparing transfusion of a single unit of RBCs following 1, 2, 3, 4, 5, or 6 weeks of storage suggests that the RBC storage lesion does not develop linearly and is only capable of inducing non-transferrin-bound iron production in healthy adult recipients following 5-6 weeks of storage. However, this relationship may differ in critically-ill populations. Furthermore, there is significant variability among blood donors in their RBC quality following storage. There are likely to be both genetic and environmental causes to this variability. Some of these causes may be donor glucose-6-phosphate dehydrogenase status, iron status, and/or dietary lipid content. In addition, in animal models, the clearance of a bolus of storage-damaged RBCs is associated with a pro-inflammatory cytokine response. Although this has yet to be demonstrated in studies using healthy adult human volunteers, studies in pediatric patient populations suggest that RBC transfusions may be associated with a pro-inflammatory response in this vulnerable population. The precise mechanism of inflammation following transfusion, and its clinical implications, has yet to be resolved. Finally, recent randomized clinical trials suggest that there are no clinical outcome differences when patients are randomized to receiving transfusions of fresh RBCs as opposed to the standard of care. Perhaps the RBC storage lesion has no clinical consequences to the transfusion recipient. However, these studies were not powered nor designed to test the effects of transfusion of RBCs during the final week of storage, in which studies suggest the effects would be most striking. Furthermore, many of the recipients in these studies already suffered from baseline hemolysis (e.g., from cardiac pump induced hemolysis, malaria, and sickle cell disease). It is unlikely that the added hemolysis from a transfusion of older RBCs would have a clinical impact given the level of baseline hemolysis from other causes observed in these patient populations. Thus, whether there are pathophysiologic consequences to the clearance of storage-damaged RBCs is still debatable. DisclosuresNo relevant conflicts of interest to declare.

Performance, feed utilization, and hepatic metabolic response of weaned juvenile Atlantic bluefin tuna (Thunnus thynnus L.): effects of dietary lipid level and source

Two trials were performed using extruded diets as on-growing feeds for weaned Atlantic bluefin tuna (Thunnus thynnus; ABT) to establish adequate dietary levels of both lipid and omega-3 long-chain polyunsaturated fatty acids (LC-PUFAs), and impacts on lipid metabolism via liver gene expression. In trial A, ABT were fed with either a commercial feed (Magokoro®; MGK) as a reference diet or two experimental feeds differing in lipid levels (15 or 20%) using krill oil (KO) as the single lipid source in order to estimate suitable lipid content. Fish fed MGK displayed the highest growth, followed by 15KO, and therefore a dietary lipid content of 15% was considered preferable to 20% at this stage. In trial B, fish were fed MGK, 15KO, or a feed containing 15% lipid with a blend of KO and rapeseed oil (RO) (1:1, v/v; 15KORO). Fish fed 15KO and 15KORO showed no difference in weight gain, specific growth rate, and fork length. Increasing dietary lipid level or including vegetable oil, RO, in the feeds did not increase liver lipid content. Liver fatty acid compositions largely reflected dietary profiles confirming very limited endogenous LC-PUFA biosynthesis. Liver of ABT fed 15KO and 20KO displayed the highest contents of docosahexaenoic acid (DHA). The hepatic expression of genes encoding enzymes and transcription factors involved in lipid and fatty acid metabolism, as well as genes encoding antioxidant enzymes, showed that many of these genes were regulated by dietary lipid and LC-PUFA content. Results suggested that ABT juveniles can be on-grown on inert dry feeds that support good fish growth and the accumulation of DHA.

Novel Feed from Invasive Species is Beneficial to Walleye Aquaculture

AbstractCarnivorous fishes, such as the Walleye Sander vitreus, are nutritionally demanding for fish meal. A promising alternative to marine‐origin fish meal, the supply of which has been stagnant in recent decades, is fish meal derived from undesirable freshwater species, such as the White Sucker Catostomus commersonii. To evaluate the relative value of such ingredients, we examined the growth performance of Walleye juveniles. Two dietary treatments were tested: an experimental (EXP) diet that was manufactured using White Sucker as fish meal in comparison with a commercial (COM) diet, EWOS Micro (EWOS Canada, Ltd.). Dietary lipid content was 15.1% and 16.8% for EXP and COM diets, respectively. The protein content was 50.4% and 57.6% for EXP and COM diets, respectively. The energy content was 5,098.76 ± 9.23 cal/g (mean ± SD) for the EXP diet and 5,134.47 ± 10.95 cal/g for the COM diet. Starting at 27 d posthatch, Walleye juveniles (initial weight [mean ± SD] = 0.03 ± 0.008 g; initial length = 15.7 ± 1.5 mm) were reared for 6 weeks in three replicate tanks for each treatment. Condition factor (0.83), final weight (1.12 ± 0.3 g), and weight gain (1.09 ± 0.06 g) were higher in fish that were fed the EXP diet. Similarly, the energetic lipid content of fish in the EXP treatment group (mean ± SD = 5.01 ± 0.45 g/kg) was also higher than that of fish fed the COM diet (3.30 ± 0.53 g/kg). Although the polar lipid content (membrane lipids) was similar in fish from the two treatments, the nutritional ratio for COM juveniles was over 1.5 for arachidonic acid and docosahexaenoic acid, indicating selective incorporation by juveniles and suggesting a potential dietary imbalance of these fatty acids. Furthermore, the higher observed selective incorporation of oleic acid in juveniles fed the EXP diet suggested that a higher value of this fatty acid in the EXP feed could have increased Walleye growth performance. Threonine was the main essential amino acid (AA; &gt;18.5% of total AAs), while serine and glycine contributed the highest percentages of the nonessential AAs (&gt;31% and 8.5% of total AAs, respectively). All three AAs, often considered limiting ingredients, are important to support growth and are involved in metabolic processes in some fish species. Our results demonstrate that feed pellets made with White Sucker fish meal improved growth in Walleye juveniles and can serve as a suitable and probably lower‐cost regional alternative to marine fish meal in feeds for carnivorous fishes.

Serum fatty acids and ischemic stroke subtypes in middle- and late-onset acute stroke patients

Summary Introduction Among stroke patients, the dietary lipid content is likely associated with the age at stroke onset and ischemic stroke subtype. Specifically, middle-onset stroke patients may have a higher serum level of saturated fatty acids and higher incidence of lacunar or atherosclerotic stroke, whereas late-onset stroke patients may have a higher serum level of n-3 polyunsaturated fatty acids (PUFA; a fish oil component) and lower incidence of lacunar or atherosclerotic stroke. This retrospective study aimed to investigate the relationships among serum fatty acid levels, age at stroke onset and stroke subtype in ischemic stroke patients. Methods Our analysis included ischemic stroke patients aged ≥50 years who were admitted to our institution within 24 h of stroke onset between September 2015 and March 2017 and underwent blood evaluations of saturated fatty acids (lauric, myristic, palmitic, stearic acids), a monounsaturated fatty acid (MUFA; oleic acid), n-6 PUFAs [linoleic, arachidonic acids (AA)] and n-3 PUFAs [alpha-linoleic, eicosapentaenoic (EPA), docosahexaenoic acids (DHA)]. We excluded patients who used statins, n-3 PUFA supplements or purified EPA drugs, fibrates or ezetimibe at onset. To compare serum levels of fatty acids and incidence rates of stroke subtypes, we stratified patients by age at stroke onset as Middle onset (50–74 years) or Late onset (≥75 years). Results One hundred ninety-one patients with an average age of 74.4 years met our inclusion criteria. Ninety-one and 100 patients were classified as Middle- and Late-onset, respectively, and these groups differed significantly in terms of mean body mass index values (23.9 vs. 22.9 kg/m2, p Conclusions People with higher serum levels of saturated fatty acids, MUFAs and n-6 PUFAs more frequently experienced lacunar or atherosclerotic stroke during middle age, whereas those with lower serum levels of these fatty acids and higher serum levels of n-3 PUFAs, such as EPA, more frequently experienced all types of ischemic stroke at an older age.

High-fat diet suppresses the positive effect of creatine supplementation on skeletal muscle function by reducing protein expression of IGF-PI3K-AKT-mTOR pathway.

High-fat (HF) diets in combination with sedentary lifestyle represent one of the major public health concerns predisposing to obesity and diabetes leading to skeletal muscle atrophy, decreased fiber diameter and muscle mass with accumulation of fat tissue resulting in loss of muscle strength. One strategy to overcome the maleficent effects of HF diet is resistance training, a strategy used to improve muscle mass, reverting the negative effects on obesity-related changes in skeletal muscle. Together with resistance training, supplementation with creatine monohydrate (CrM) in the diet has been used to improve muscle mass and strength. Creatine is a non-essential amino acid that is directly involved in the cross-bridge cycle providing a phosphate group to ADP during the initiation of muscle contraction. Besides its antioxidant and anti-inflammatory effects CrM also upregulates IGF-1 resulting in hyperthophy with an increase in muscle function. However, it is unknown whether CrM supplementation during resistance training would revert the negative effects of high-fat diet on the muscle performance. During 8 weeks we measured muscle performance to climb a 1.1m and 80° ladder with increasing load on trained rats that had received standard diet or high-fat diet, supplemented or not with CrM. We observed that the CrM supplementation up-regulated IGF-1 and phospho-AKT protein levels, suggesting an activation of the IGF1-PI3K-Akt/PKB-mTOR pathway. Moreover, despite the CrM supplementation, HF diet down-regulated several proteins of the IGF1-PI3K-Akt/PKB-mTOR pathway, suggesting that diet lipid content is crucial to maintain or improve muscle function during resistance training.

Paradoxical Protective Effect of Perfluorooctanesulfonic Acid Against High-Fat Diet-Induced Hepatic Steatosis in Mice.

Perfluorooctanesulfonic acid (PFOS) is a persistent organic pollutant with worldwide bioaccumulation due to a very long half-life. Perfluorooctanesulfonic acid exposure results in significant hepatic effects including steatosis, proliferation, hepatomegaly, and in rodents, carcinogenesis. The objective of this study was to determine whether PFOS exposure exacerbates nonalcoholic fatty liver disease and nonalcoholic steatohepatitis pathogenesis. Eight-week-old male C57BL/6 J mice (n = 5 per group) were fed ad libitum normal chow diet (ND) alone, 60% high-fat diet (HFD) alone, ND + PFOS, and HFD + PFOS (0.0001% w/w (1 mg/kg) of PFOS) for 6 weeks. Both HFD alone and the ND + PFOS treatment induced significant adiposity and hepatomegaly, but the HFD + PFOS treatment showed a marked protection. Oil Red O staining and quantitative analysis of hepatic lipid content revealed increased hepatic steatosis in ND + PFOS and in HFD alone fed mice, which was prevented in HFD + PFOS treatment. Further studies revealed that ND + PFOS treatment significantly affected expression of lipid trafficking genes to favor steatosis, but these changes were absent in HFD + PFOS group. Specifically, expression of CD36, the major lipid importer in the cells, and peroxisome proliferator-activated receptor gamma (PPARγ), its major regulator, were induced in HFD + no treatment (NT) and ND + PFOS-fed mice but remained unchanged in HFD + PFOS mice. In conclusion, these data indicate that coadministration of PFOS with HFD mitigates steatosis and hepatomegaly induced by HFD and that by PFOS fed in ND diet via regulation of cellular lipid import machinery. These findings suggest dietary lipid content be considered when performing risk management of PFOS in humans and the elucidation of PFOS-induced hepatotoxicity.

Effect of dietary lipid content and stocking density on digestive enzymes profile and intestinal histology of rainbow trout (Oncorhynchus mykiss)

The effect of both dietary lipid level and stocking density on digestive function was tested in young rainbow trout under culture conditions. Two dietary lipid levels (14 and 33%) and three culture densities (15, 30 and 40 kg/m3) were assayed in triplicate lots: L14/D15, L14/D30, L14/D40, L33/D15, L33/D30 and L33/D40. Intestinal activities of amylase, lipase, trypsin, chymotrypsin, total protease (at different pHs) as well as some biometric parameters such hepatosomatic index (HSI) and digestivesomatic index (DSI) as indicative of perivisceral fat accumulation, were determined after a 12-weeks experimental period. A histological study of intestine was carried on to evaluate changes in tissue architecture. Fish fed on higher lipid diets grew more and accumulated a higher amount of fat in perivisceral tissue, although higher stocking density reduced this trend. According to digestive capacity, higher lipid intake induced an activation of lipase activity that was not apparent when fish were held under the highest rearing density. By other hand, dietary lipids promoted a significant inhibition of protease activity in fish under high density conditions. These results seem to indicate a clear interaction between both variables. In this study, it was manifested a general effect of dietary lipids level and culture density on digestive profile. These interactions should be taken into account when foreseeing the digestive utilization of a commercial feed at different culture conditions to improve fish production.