Plasma Triacylglyceride Research Articles

Proteomic analysis of plasma-derived extracellular vesicles: pre- and postprandial comparisons

Extracellular vesicles (EVs) are key in intercellular communication, carrying biomolecules like nucleic acids, lipids, and proteins. This study investigated postprandial characteristics and proteomic profiles of blood-derived EVs in healthy individuals. Twelve participants fasted overnight before baseline assessments. After consuming a controlled isocaloric meal, EVs were isolated for proteomic and flow cytometric analysis. Plasma triacylglyceride levels confirmed fasting completion, while protein concentrations in plasma and EVs were monitored for postprandial stability. Proteomic analysis identified upregulated proteins related to transport mechanisms and epithelial/endothelial functions postprandially, indicating potential roles in physiological responses to nutritional intake. Enrichment analyses revealed vesicle-related pathways and immune system processes. Flow cytometry showed increased expression of CD324 on CD9+CD63+CD81+ large extracellular vesicles postprandially, suggesting an epithelial origin. These findings offer valuable insights into postprandial EV dynamics and their potential physiological significance, highlighting the need for stringent fasting guidelines in EV studies to account for postprandial effects on EV composition and function.

Effect of seminal plasma cholesterol and triacylglycerides concentrations and sperm morphology on semen freezability in domestic cats (Felis silvestris catus)

There is scarce information about the effect of sperm morphology and seminal plasma composition on cat semen freezability. Thus, this study aims to assess the effect of cat sperm morphology and seminal plasma cholesterol (CHOL) and triacylglyceride (TAG) concentrations on sperm post-thaw survival. Ejaculates (n = 49) were evaluated, and seminal plasma was separated and frozen until CHOL and TAG concentrations were measured. The sperm pellet was diluted in a tris-based egg yolk extender, frozen (n = 38), or processed for sperm ultrastructure study (n = 11). Abnormalities recorded were abnormal head shape and size, detached heads, knobbed or ruffled acrosomes, eccentric mid-piece insertion, proximal and distal cytoplasmic droplets, folded and coiled tails, and Dag defect. Ultramicroscopic evaluation detected several sperm abnormalities in fresh semen and some sperm damage in frozen semen. Seminal plasma lipids components were positively correlated with post-thaw motility and acrosome integrity. Higher freezability indices for motility and acrosome integrity were observed in frozen-thawed semen with high seminal plasma CHOL and TAG concentrations. No freezability differences were observed between teratozoospermic and normozoospermic ejaculates. Our results showed that even when seminal plasma was removed before cryopreservation, sperm survival after thawing was significantly higher in samples with high seminal plasma CHOL and TAG concentrations, indicating a rapid adherence to these compounds to the sperm plasma membrane, protecting sperm cells from temperature changes. Nevertheless, there were no differences in sperm freezability by sperm morphology.

Abstract 2044: Disruption Of DENND5B Attenuates Triglyceride-rich Lipoprotein Secretion From Human Enterocytes And Hepatocytes

Background and Hypothesis: Elevated plasma triacylglycerides (TAGs) are an established risk factor for atherosclerotic cardiovascular disease, and are regulated by dietary absorption via the small intestine and endogenous production by the liver. Our laboratory formerly reported that Dennd5b -deficient mice are protected from diet-induced hepatic steatosis, hyperlipidemia, and atherosclerosis. Electron microscopy imaging of the intestinal epithelium of Dennd5b -/- mice reveals significant lipid accumulation in intracellular chylomicron secretory vesicles, suggesting a post-Golgi chylomicron secretion defect. Given that Dennd5b is expressed by the two major triglyceride-rich lipoprotein (TRL)-secreting organs (liver and small intestine), we hypothesized that disruption of DENND5B attenuates TRL secretion in both of these cell types in humans. Methods and Results: To determine if DENND5B disruption impairs TRL secretion in human cells, we generated DENND5B -/- intestinal epithelial (Caco-2) and hepatocyte (HepG2) cell lines using CRISPR gene editing. Western blots verified DENND5B protein reduction in DENND5B -/- cells. The impact of DENND5B deficiency on TRL secretion was quantified by measuring the cellular and secreted TAG content of DENND5B +/+ and DENND5B -/- cells under standard growth conditions and after oleic acid loading. Caco-2 cells were differentiated on membrane supports for 21 days prior to experiments. DENND5B -/- Caco-2 cells secreted significantly less TAGs compared to wild-type Caco-2 cells (-67.8%, p<0.0001). DENND5B -/- HepG2 cells also had significantly reduced TAG secretion (-91.0%, p<0.0001). Disruption of DENND5B in both cell lines reduced TAG secretion without affecting cellular TAG content. Immunofluorescence microscopy showed intracellular DENND5B protein localization consistent with secretory pathway involvement with detection on a perinuclear structure (likely Golgi), cytosolic vesicles, and plasma membrane. Conclusions: These studies suggest that DENND5B plays a role in TRL secretion from human enterocytes and hepatocytes and provide new model systems for investigating the molecular function of DENND5B in TRL secretion from human cells.

Abstract 118: Dennd5b Affects Dietary Lipid Absorption And Metabolism In Male And Female Mice

Background: Dietary lipid absorption by the intestine is essential for systemic lipid homeostasis. We previously demonstrated a role for Dennd5b in intestinal lipid absorption. In humans, DENND5B gene variants are correlated with BMI in females, but not males. Female Dennd5b -/- mice have reduced appearance of dietary triacylglyceride (TAG) in plasma and are resistant to diet-induced obesity, however, the metabolic impact of Dennd5b -/- in male mice has not been reported. In this study, we test the hypothesis that the Dennd5b -/- mouse model recapitulates the sex disparity observed in humans with DENND5B polymorphisms. We also investigate the fate of unsecreted intestinal TAG in this model of impaired dietary lipid absorption. Methods and Results: A non-absorbable fatty acid (FA) tracer was used to quantify the impact of Dennd5b -deficiency on lipid absorption in male and female mice (n=7-9 mice/genotype/sex). We observed significant, but relatively modest, reductions in lipid absorption efficiency in Dennd5b -/- mice in both sexes, despite a complete absence of plasma TAG after oil gavage. We hypothesized that this was due to metabolic utilization of TAG by enterocytes. Metabolic cage studies showed that both wildtype and Dennd5b -/- mice shift toward utilization of FAs when fed high-fat diet and Seahorse analysis revealed altered metabolic activity in Dennd5b -/- intestinal tissue. Electron microscopy (EM) revealed large electron dense structures that resemble autophagosomes in Dennd5b -/- enterocytes. Western blots detected altered Lc3 levels in Dennd5b -/- intestine, implicating autophagy. RNA sequencing of intestinal tissue detected changes in expression of genes involved in beta oxidation and EM imaging revealed altered mitochondrial morphology in Dennd5b -/- enterocytes. Conclusions: We conclude that autophagy contributes to degradation of unsecreted TAG in the Dennd5b -/- enterocytes, liberating free FAs which are utilized in mitochondrial oxidation. The sexually dimorphic effect of Dennd5b does not appear to be as prominent in mice as it is in humans. Overall, our findings demonstrate that Dennd5b plays a critical role in TAG secretion by intestinal tissue and that disruption of this process can impact systemic metabolism in both sexes.

Analysis of Hepatic Lipid Metabolism Model: Simulation and Non-Stationary Global Sensitivity Analysis

Lipid metabolism is a complex process and it is extremely helpful to simulate its performance with different models that explain all the biological processes that comprise it, which then enables its better understanding as well as understanding the kinetics of the process itself. Typically, kinetic parameters are obtained from a number of sources under specific experimental conditions, and they are a source of uncertainty. Sensitivity analysis is a useful technique for controlling the uncertainty of model parameters. It evaluates a model's dependence on its input variables. In this work, hepatic lipid metabolism was mathematically simulated and analyzed. Simulations of the model were performed using different initial plasma glucose (GB) and plasma triacylglyceride (TAG) concentrations according to proposed menus for different meals (breakfast, lunch, snack and dinner). A non-stationary Fourier amplitude sensitivity test (FAST) was applied to analyze the effect of 78 kinetic parameters on 24 metabolite concentrations and 45 reaction rates of the biological part of the hepatic lipid metabolism model at five time points (tf = 10, 50, 100, 250 and 500 min). This study examined the total influence of input parameter uncertainty on the variance of metabolic model predictions. The majority of the propagated uncertainty is due to the interactions of numerous factors rather than being linear from one parameter to one result. Obtained results showed differences in the model control regarding the different initial concentrations and also the changes in the model control over time. The aforementioned knowledge enables dietitians and physicians, working with patients who need to regulate fat metabolism due to illness and/or excessive body mass, to better understand the problem.

Beneficial effects of substituting soybean meal for white lupin (Lupinus albus, cv. Zulika) meal on the biochemical blood parameters of laying hens

The experiment aimed to determine the effect of substituting 50% of soy protein for lupin protein in feed mixtures intended for the nutrition of high-yield Isa Brown laying hens, on selected biochemical blood plasma indicators. The trial was designed as a long-lasting feeding experiment (51 weeks) and involved a total of 180 hens divided in three experimental groups (control group C and experimental groups WLS and WDLS). At the end of the laying cycle, blood samples were taken from the hens by puncture of the vena basilica and subsequently, the required blood plasma indicators were analysed in the laboratory. The results demonstrated that the long-term feeding of white lupin (variety Zulika) did not affect the molar concentration of plasma inorganic phosphorus (P), magnesium (Mg), sodium (Na), potassium (K), chloride (Cl), uric acid (UAC) and the activity of alanine aminotransferase (AST). By contrast, the substitution of soy protein for lupin protein in the diets of the experimental groups of laying hens led to the statistically significant (p ≤ .05) decrease of total plasma protein (TP), total cholesterol (Chol), calcium (Ca) and triacylglycerides (TAG) and to an increase (p ≤ .05) of alkaline phosphatase activity (ALP). Highlights Replacement of soya protein with white lupin protein reduced cholesterol and triacylglycerides in blood plasma Feedstuff including white lupin protein did not affect negatively the health status of the layers

Metabolic characterisation of disturbances in the APOC3/triglyceride-rich lipoprotein pathway through sample-based recall by genotype

IntroductionHigh plasma triacylglyceride levels are known to be associated with increased risk of atherosclerotic cardiovascular disease. Apolipoprotein C-III (apoC-III) is a key regulator of plasma triacylglyceride levels and is associated with hypertriglyceridemia via a number of pathways. There is consistent evidence for an association of cardiovascular events with blood apoC-III level, with support from human genetic studies of APOC3 variants. As such, apoC-III has been recognised as a potential therapeutic target for patients with severe hypertriglyceridaemia with one of the most promising apoC-III-targeting drugs, volanesorsen, having recently progressed through Phase III trials.ObjectivesTo exploit a rare loss of function variant in APOC3 (rs138326449) to characterise the potential long-term treatment effects of apoC-III targeting interventions on the metabolome.MethodsIn a recall-by-genotype study, 115 plasma samples were analysed by UHPLC-MS to acquire non-targeted metabolomics data. The study included samples from 57 adolescents and 33 adults. Overall, 12 985 metabolic features were tested for an association with APOC3 genotype.Results144 uniquely annotated metabolites were found to be associated with rs138326449(APOC3). The highest proportion of associated metabolites belonged to the acyl-acyl glycerophospholipid and triacylglyceride metabolite classes. In addition to the anticipated (on-target) reduction of metabolites in the triacylglyceride and related classes, carriers of the rare variant exhibited previously unreported increases in levels of a number of metabolites from the acyl-alkyl glycerophospholipid and ceramide classes.ConclusionOverall, our results suggest that therapies targeting apoC-III may potentially achieve a broad shift in lipid profile that favours better metabolic health.

Dehulling effect of dietary administered white lupine seeds on the blood biochemistry of broilers

The aim of the study was to assess the effect of the partial or complete dietary replacement of crude protein (CP) from soybean meal (SBM) with CP from the meal of whole (trial 1) or dehulled (trial 2) white lupine (WL) seeds on the blood plasma biochemical indicators in broilers. Chickens of the control (C) group were fed diets containing the SBM as the main protein source in the feed. It results from the findings that the complete and also partial replacement of CP from the SBM by CP from the meal of whole WL seeds in diets led to a decrease in the plasma cholesterol and triacylglycerides (TAG) levels (P < 0.001). Concerning the dietary administration of dehulled WL seeds, only the complete replacement of CP resulted in a decrease in the plasma glucose and TAG levels in 35-day-old broilers (P < 0.05). In addition, when including the dehulled WL seeds into the diet, an increase in the plasma aspartate aminotransferase activity was found in both the E1 and E2 groups (P < 0.01). Based on the results found, it can be stated that the use of meal from whole WL seeds seems to be a promising protein feed component which has beneficial effects on the health of broilers.

Effects of Lactobacillus plantarum Uruma-SU4 fermented green loofah on plasma lipid levels and gut microbiome of high-fat diet fed mice

To clarify the effect of loofah Luffa cylindrica and fermented loofah on hyperlipidemia, the in vitro bile acid lowering capacity and blood lipid levels of ddY mice fed high-fat diet supplemented with loofah were determined. Furthermore, the caecal microbiomes patterns were analysed using 16S rDNA amplicon sequencing with a next generation sequencer (MiSeq) system. Green loofah was homogenized and autoclaved (LH), and subsequently fermented with Lactobacillus plantarum Uruma-SU4 (FL). In vitro bile acid (taurocholic, glycocholic and deoxycholic acids (DCA)) lowering capacity was significantly high in FL. The levels of plasma triacylglyceride in mice which were fed a high-fat diet containing 17% beef tallow was lowered by 5% dried FL (FLD) and was unaffected by dried LH (LHD). Caecal Lactobacillus johnsonii and Clostridium disporicum known as predominant lactic acid bacteria in mice gut and urso-DCA producer, respectively, were increased by FLD. On the other hand, Flintibacter butyricus was lowered by both LHD and FLD. These results suggest that if green loofah cannot be consumed as a fresh vegetable, lactic acid fermentation may be useful in generating effective nutritional supplements and functional foods.

Energy and nitrogen partitioning in dairy cows at low or high metabolizable protein levels is affected differently by postrumen glucogenic and lipogenic substrates

This study tested the effects of energy from glucogenic (glucose; GG) or lipogenic (palm olein; LG) substrates at low (LMP) and high (HMP) metabolizable protein levels on whole-body energy and N partitioning of dairy cattle. Six rumen-fistulated, second-lactation Holstein-Friesian dairy cows (97 ± 13 d in milk) were randomly assigned to a 6 × 6 Latin square design in which each experimental period consisted of 5 d of continuous abomasal infusion followed by 2 d of rest. A total mixed ration consisting of 42% corn silage, 31% grass silage, and 27% concentrate (dry matter basis) was formulated to meet 100 and 83% of net energy and metabolizable protein requirements, respectively, and was fed at 90% of ad libitum intake by individual cow. Abomasal infusion treatments were saline (LMP-C), isoenergetic infusions (digestible energy basis) of 1,319 g/d of glucose (LMP-GG), 676 g/d of palm olein (LMP-LG; major fatty acid constituents are palmitic, oleic, and linoleic acid), or 844 g/d of essential AA (HMP-C), or isoenergetic infusions of 1,319 g/d of glucose + 844 g/d of essential AA (HMP-GG) or 676 g/d of palm olein + 844 g/d of essential AA (HMP-LG). The experiment was conducted in climate respiration chambers to determine energy and N balance in conjunction with milk production and composition, nutrient digestibility, and plasma constituents. Infusion of GG and LG decreased dry matter intake, but total gross energy intake from the diet plus infusions was not affected by GG or LG. Furthermore, GG or LG did not affect total milk, protein, or lactose yields. Infusing GG or LG at the HMP level did not affect milk production differently than at the LMP level. Infusion of GG stimulated energy retention in body tissue, increased plasma glucose and insulin concentrations, decreased lipogenic metabolites in plasma, and decreased milk fat yield and milk energy output. Nitrogen intake decreased and milk N efficiency increased in response to GG, and N retention was not affected. Infusion of LG tended to increase metabolizable energy intake, increased milk fat yield and milk energy output, increased plasma triacylglycerides and long-chain fatty acid concentrations, and had no effect on energy retention. Infusion of LG decreased N intake but did not affect milk N efficiency or N retention. Compared with the LMP level, the HMP level increased dry matter intake, gross and metabolizable energy intake, and total milk, fat, protein, and lactose yields. Milk energy output increased at the HMP level, and protein level did not affect total energy retention. Heat production increased at the HMP level, but only when GG and LG were infused. The HMP level increased N intake, milk N output, and plasma urea concentration, tended to increase N retention, and decreased milk N efficiency. Regardless of protein level, GG promoted energy retention and improved milk N efficiency, but not through increased milk protein yield. Infusion of LG partitioned extra energy intake into milk and had no effect on milk N efficiency.

Selected Physiological Effects of a Garcinia Gummi-Gutta Extract in Rats Fed with Different Hypercaloric Diets.

Garcinia gummi-gutta (GGG) rind extract is effective for reducing appetite, body weight and adiposity of obese rodents fed high-fat (HF), high-sugar (HS) or high fat/sugar (HFS)-based diets, but these effects have not been simultaneously evaluated. Thirty obese (~425 g) male Wistar rats were fed for eleven weeks with six hypercaloric diets (4.1 kcal/g; five rats/diet) non-supplemented (HF, HS, HFS), or supplemented (HF+, HS+, HFS+) with GGG extract (5.9%), while rats from the control group (375 g) were fed a normocaloric diet (3.5 kcal/g). Body weight, dietary intake, body fat distribution, and histological and biochemical parameters were recorded. Compared to control rats, non-supplemented and supplemented groups consumed significantly less food (14.3% and 24.6% (−4.3 g/day), respectively) (p < 0.05). Weight loss was greater in the HF+ group (35–52 g), which consumed 1.9 times less food than the HS+ or HFS+ fed groups. The HF and HFS groups showed 40% less plasma triacylglycerides and lower glucose levels compared to the HF+. GGG-supplemented diets were associated with lower ketonuria. The HF+ diet was associated with the best anti-adiposity effect (as measured with the dual X-ray absorptiometry (DXA) and Soxhlet methods). The severity of hepatocyte lipidosis was HF > control > HF+, and no signs of toxicity in the testes were observed. The results indicate that GGG is more effective when co-administered with HF diets in obese rats.

Effects of vitamin D3 on endoplasmic reticulum stress in adipose tissue and insulin resistance induced by high fat diet in mice

Objective To study the effect of vitamin D3 on adipose tissue endoplasmic reticulum stress and insulin resistance induced by high fat diet in mice. Methods Eighty male C57BL/6 mice were divided into control group(n=20)and experimental group(n=60), fed with common food and high fat diet, respectively. After the establishment of the obesity model, the experimental mice were divided into control group, low-dose(50 IU/kg)vitamin D3 group(VitD-L), and high-dose(250 IU/kg)vitamin D3 group(VitD-H). After the mice were fed for 1 week, Western blot was used to detect the expressions of immunoglobulin heavy chain-binding protein(Bip), phosphorylated inositol-requiring enzyme 1(p-IRE1), phosphorylated protein kinase R(PKR)-like endoplasmic reticulum kinase(p-PERK), and NF-κB protein in adipose tissue. Serum levels of TNF-α, IL-6, serum 25-hydroxyvitamin D, fasting plasma glucose, HbA1C, triacylglyceride, and fasting insulin were measured and the insulin resistance index was calculated. Results Vitamin D3 down-regulated the expressions of endoplasmic reticulum stress key genes including Bip, p-IRE1, and p-PERK; and decreased the protein expression of NF-κB and the serum levels of TNF-α and IL-6(P<0.05). Vitamin D3 also significantly reduced the levels of fasting blood glucose, HbA1C, triacylglyceride, and fasting insulin in obese mice(P<0.05), while alleviated the insluin resistance in obese mice. Conclusion Vitamin D3 may significantly improve inflammatory response and insulin resistance via inhibiting endoplasmic reticulum stress in adipose tissue of obese mice. (Chin J Endocrinol Metab, 2017, 33: 861-864) Key words: Obesity; Vitamin D3; Endoplasmic reticulum stress; Insulin resistance

Sex specific differences in hepatic and plasma lipid profiles in healthy cats pre and post spaying and neutering: relationship with feline hepatic lipidosis

BackgroundA link between lipid metabolism and disease has been recognized in cats. Since hepatic lipidosis is a frequent disorder in cats, the aim of the current study was to evaluate liver and plasma lipid dimorphism in healthy cats and the effects of gonadectomy on lipid profiling. From six female and six male cats plasma and liver lipid profiles before and after spaying/neutering were assessed and compared to five cats (three neutered male and two spayed female) diagnosed with hepatic lipidosis.ResultsIntact female cats had a significantly lower level of plasma triacylglycerides (TAG) and a higher liver level of the long chain polyunsaturated fatty acid arachidonic acid (AA) compared to their neutered state. Both male and female cats with lipidosis had a higher liver, but not plasma TAG level and an increased level of plasma and liver sphingomyelin compared to the healthy cats.ConclusionAlthough lipid dimorphism in healthy cats resembles that of other species, intact female cats show differences in metabolic configuration that could predispose them to develop hepatic lipidosis. The increased sphingomyelin levels in cats with lipidosis could suggest a potential role in the pathogenesis of hepatic lipidosis in cats.

Detailed fatty acid profile of serum lipid classes in lactating women and their relationship with milk fat

Little is known about fatty acid (FA) distribution among triacylglyceride (TG), cholesterol ester (CE), and phospholipid (PL) plasma lipid fractions in lactating women, and the relationships between these fractions and the FA profile of the milk that mothers produce. Milk fat and serum lipid FA compositions in lactating women were compared to investigate which serum lipids are the source of FA in milk fat. A TLC methodology was used to fractionate serum lipids including PL subclasses, that is, phosphatidylethanolamine (PE), phosphatidylcholine (PC), and sphingomyelin (SM). Plasma lipids consisted of CE (36.4%), TG (19.1%), PE (1.40%), PC (39.80%), and SM (3.29%). With regard to PL fractions, PE was characterized by the highest levels of 18:0, 20:4 n‐6, 22:6 n‐3, and alkenyl ethers. PC revealed 16:0 as the predominant FA, followed by 18:2 n‐6, 18:0, cis‐9 18:1, and 20:4 n‐6, whereas saturated FA from 16:0 to 24:0 were characteristic of SM. Although n‐6 and n‐3 polyunsaturated FA were mostly found in PE and PC, strong correlations were found for 18:2 n‐6 and 18:3 n‐3 between plasma TG and milk lipids. This study also shows that trans 18:1 isomers may be selectively incorporated into milk fat from specific serum fractions.Practical applications:An easy‐to‐use and inexpensive two‐stage TLC methodology to fractionate plasma lipids requiring only 1 mL of blood serum has been developed. Moreover, this study provides valuable information on the composition of serum lipids in lactating women, particularly with regard to PL classes, and their influence on the milk fat FA profile.Fatty acid transfer from serum lipids to milk fat in lactating women.

Antiobesity Effect of Garlic Extract Fermented by Lactobacillus plantarum BL2 in Diet-Induced Obese Mice.

Obesity is viewed as a serious public health problem. This study aimed to investigate the antiobesity effects of fermented garlic extract by lactic acid bacteria (LAFGE) on obesity. Male C57BL/6J mice were fed with high-fat diet (HFD) to induce obesity. The HFD-induced obese mice were orally administrated with 250 or 500 mg/kg LAFGE for 8 weeks. Feeding HFD-fed mice with 250 or 500 mg/kg LAFGE reduced body weight by 14% and 18%, respectively, compared to HFD. HFD-fed mice with 500 mg/kg LAFGE administration had lower epididymal, retroperitoneal, and mesenteric adipose tissue mass by 36%, 44%, and 63%, respectively, compared to HFD. The concentration of plasma triacylglyceride and total cholesterol was significantly lower in the HFD-fed mice with LAFGE administration. Moreover, LAFGE supplementation suppressed adipogenesis by downregulation in mRNA and protein expression of PPARγ, C/EBPα, and lipogenic proteins, including SREBP-1c, FAS, and SCD-1. Based on these findings, LAFGE may ameliorate diet-induced obesity by inhibiting adipose tissue hypertrophy by suppressing adipogenesis.

METABOLIC EFFECTS OF Β-GLUCANS (SACCHAROMYCES CEREVISAE) PER OS ADMINISTRATION IN RATS WITH STREPTOZOTOCIN-INDUCED DIABETES.

beta-glucans (BG) derived from plant tissues are reported to show metabolic effects. In contrast, those fibers isolated from yeast seem to be more related to immune response modulation. Since diabetic individuals are more susceptible to exacerbation of inflammatory signs, the ingestion of fibers that could conjugate both metabolic and immune effects would be of great importance. we investigated the effect of BG - Saccharomyses cerevisae - ingestion on glycemic and lipoprotein profile of diabetic rats. twenty-four adult Wistar rats were used, distributed into 4 groups in a design of entirely casualized delineation with a 2 x 2 factorial model (with and without diabetes; with and without BG). Diabetes Mellitus was induced by an intraperitoneal injection of 80mg/kg of strepzotocin. Thus, animals with fasting glycemia of over 250 mg/dl were considered diabetic. Forty-eight hours after induction, the rats received daily doses of 30 mg/kg of BG or saline solution by gavage during 28 days. the Groups with DM presented a higher glycemic index and lower C peptide levels than the control groups, in addition to lower weight gain and higher ration consumption, water ingestion and urinary volume. Total cholesterol levels (CT), LDL-C + VLDL-C, plasma triacylglycerides (TAG) and alanine aminotransferase (ALT) were also higher in the diabetic animals (p < 0.05), and there were no alterations in the HDL-C levels. The ingestion of BG reduced blood glucose concentrations (30%), TAG (32%) and ALT (41%) (p < 0.05). No histopathological hepatic alterations were observed in any of the groups. Furthermore, the diabetic animals present increase in villous:crypt ratio (V:C) in the duodenum, without interference of BG. No alterations in the carcass were observed between the groups. it was concluded that the use of BG significantly reduced the glycemic, TAG and ALT levels, showing its therapeutic potential.

Utilization of dietary starch by juvenile white sea breamDiplodus sargusat different feeding frequencies

To assess the effect of feeding frequency on the utilization of dietary starch by white sea bream juveniles, triplicate groups of fish were fed an experimental diet (400 g kg−1 protein, 140 g kg−1 lipids and 350 g kg−1 pregelatinized maize starch) to apparent visual satiation 2, 3 or 4 times a day for 63 days. Growth performance, feed utilization efficiency, glycaemia, cholesterolaemia, plasma triacylglycerides, liver lipids and glycogen content were unaffected by feeding frequency. α-Amylase activity increased from the pyloric caeca to the posterior intestine and was higher in fish fed twice a day than in fish fed 3 or 4 times a day. Hepatic glucokinase (GK) activity decreased with the increase in feeding frequencies, whereas fructose-1,6-bisphosphatase (FBPase) activity increased. Hepatic glucose-6-phosphate dehydrogenase and glutamate dehydrogenase activities were unaffected by feeding frequency. Overall, feeding frequency did not improve white sea bream dietary starch utilization. α-Amylase, GK and FBPase activities responded to dietary starch consumed at each meal, denoting a good metabolic adaptation of the fish to the feeding conditions.

Scallop protein with endogenous high taurine and glycine content prevents high-fat, high-sucrose-induced obesity and improves plasma lipid profile in male C57BL/6J mice

High-protein diets induce alterations in metabolism that may prevent diet-induced obesity. However, little is known as to whether different protein sources consumed at normal levels may affect diet-induced obesity and associated co-morbidities. We fed obesity-prone male C57BL/6J mice high-fat, high-sucrose diets with protein sources of increasing endogenous taurine content, i.e., chicken, cod, crab and scallop, for 6 weeks. The energy intake was lower in crab and scallop-fed mice than in chicken and cod-fed mice, but only scallop-fed mice gained less body and fat mass. Liver mass was reduced in scallop-fed mice, but otherwise no changes in lean body mass were observed between the groups. Feed efficiency and apparent nitrogen digestibility were reduced in scallop-fed mice suggesting alterations in energy utilization and metabolism. Overnight fasted plasma triacylglyceride, non-esterified fatty acids, glycerol and hydroxy-butyrate levels were significantly reduced, indicating reduced lipid mobilization in scallop-fed mice. The plasma HDL-to-total-cholesterol ratio was higher, suggesting increased reverse cholesterol transport or cholesterol clearance in scallop-fed mice in both fasted and non-fasted states. Dietary intake of taurine and glycine correlated negatively with body mass gain and total fat mass, while intake of all other amino acids correlated positively. Furthermore taurine and glycine intake correlated positively with improved plasma lipid profile, i.e., lower levels of plasma lipids and higher HDL-to-total-cholesterol ratio. In conclusion, dietary scallop protein completely prevents high-fat, high-sucrose-induced obesity whilst maintaining lean body mass and improving the plasma lipid profile in male C57BL/6J mice.Electronic supplementary materialThe online version of this article (doi:10.1007/s00726-014-1715-1) contains supplementary material, which is available to authorized users.

DHA attenuates postprandial hyperlipidemia via activating PPARα in intestinal epithelial cells

It is known that peroxisome proliferator-activated receptor (PPAR)α, whose activation reduces hyperlipidemia, is highly expressed in intestinal epithelial cells. Docosahexaenoic acid (DHA) could improve postprandial hyperlipidemia, however, its relationship with intestinal PPARα activation is not revealed. In this study, we investigated whether DHA can affect postprandial hyperlipidemia by activating intestinal PPARα using Caco-2 cells and C57BL/6 mice. The genes involved in fatty acid (FA) oxidation and oxygen consumption rate were increased, and the secretion of triacylglyceride (TG) and apolipoprotein B (apoB) was decreased in DHA-treated Caco-2 cells. Additionally, intestinal FA oxidation was induced, and TG and apoB secretion from intestinal epithelial cells was reduced, resulting in the attenuation of plasma TG and apoB levels after oral administration of olive oil in DHA-rich oil-fed mice compared with controls. However, no increase in genes involved in FA oxidation was observed in the liver. Furthermore, the effects of DHA on intestinal lipid secretion and postprandial hyperlipidemia were abolished in PPARα knockout mice. In conclusion, the present work suggests that DHA can inhibit the secretion of TG from intestinal epithelial cells via PPARα activation, which attenuates postprandial hyperlipidemia.

Global Inactivation of the Pla2g6 Gene in Mice Does Not Cause Dyslipidemia under Chow or High-fat Diet Conditions.

Background:Genome-wide association studies suggest that plasma triacylglyceride (TAG) in humans was associated with variation in the PLA2G6 locus, a gene that encodes calcium-independent phospholipase A2 (iPLA2β). The objective of the present study is to understand the impact of genetic inactivation of iPLA2β on hepatic TAG metabolism in C57BL/6 mice.Methods:Male iPLA2β+/− mice were backcrossed with female iPLA2β−/− mice for up to 10 generations prior to experiments. Lipid and lipoprotein metabolism from plasma, hepatocytes, thigh subcutaneous adipose and thigh skeletal muscle tissues of the mice were determined under various experimental conditions.Results:The iPLA2β−/− mice, either male or female as compared with iPLA2β+/+ littermates, showed no change in fasted or postprandial plasma TAG or total cholesterol at young (12–15 weeks) or old (40–44 weeks) ages under chow diet or high-fat diet (HFD) conditions. However, fractionation of plasma lipoproteins showed that under HFD conditions, there was a significant increase (by 40%) in apoB-100 association with VLDL1 fractions in iPLA2β−/− mice as compared with iPLA2β+/+ littermates. There was no significant difference in triglyceride or cholesterol contents in the liver, muscle, or adipose tissue between iPLA2β−/− and iPLA2β+/+ littermates. Metabolic labeling experiments with cultured primary hepatocytes isolated from iPLA2β−/− mice also showed 2-fold increase in the secretion of [35S]methionine-labeled apoB-100 in VLDL1 fractions as compared with that from iPLA2β+/+ hepatocytes. Likewise, secretion of [3H]palmitate-labeled TAG from the iPLA2β−/− hepatocytes was increased by 2-fold.Conclusions:Although iPLA2β may play a role in TAG-rich VLDL1 production from cultured hepatocytes, there is no evidence that inactivation of iPLA2β would lead to dyslipidemia in mice in vivo.