Dietary Lipid Research Articles

Effects of different dietary lipid levels on physiological metabolism and odor quality of hepatopancreas in adult female Chinese mitten crab (Eriocheir sinensis)

Abstract Objectives This study aimed to investigate the impact of different dietary lipid levels on the physiological metabolism and odor quality of adult female Eriocheir sinensis during the fattening phase. Materials and Methods Five dietary schemes, each containing different total lipid levels (4%, 7%, 10%, 13%, and 16%), were administered over a 60-d fattening period for adult female crab (approximately 50 g, n=60). Chromatography and spectroscopy techniques were used for the detection of aroma and key aroma precursors. Results Dietary lipids had no significant effect on growth performance and hepatopancreas index (P<0.05). The carotenoid content showed an increasing and then decreasing trend, with a significant increase to 1312.51 mg/kg (P<0.05) at 7% lipid content of the diet. In contrast, a diet with a 13% lipid level led to a significant increase in total unsaturated fatty acids (115.3 mg/g, P<0.05), which maximized the contents of major fatty acids (oleic, linoleic, and linolenic, among others), and presented a fluctuating trend. A diet with higher lipid levels (16%) inhibited fatty acid accumulation. Moreover, a 13% dietary lipid level enhanced characteristic aroma compounds (for example, nonanal, octanal, hexanal, 3-methylbutanal, and 2-heptanone) in E. sinensis cooked hepatopancreas. Through an orthogonal partial least squares discriminant analysis model, it becomes evident that lipids and carotenoids together promote aroma formation in hepatopancreas. Conclusions Based on the current findings, the optimal dietary lipid level for enhancing the odor quality of hepatopancreas in adult female E. sinensis during the fattening phase was 13%. This study provides more precise options for the high-quality cultivation of E. sinensis.

The effects of isocaloric diets derived from different lipid sources on zebrafish.

Characterizing the effects of saturated fat intake on metabolic health and its changes remains a major challenge. Lipid diets, from different sources, vary widely in their physiological effects on health; therefore, it is important to consider the specific lipid source consumed. The objective of the study was to evaluate the effect of the imposition of isocaloric diets with different lipid sources in zebrafish (fish oil/pork lard). Depicting how metabolic, morphological and behavioral parameters might express themselves in these fishes. Forty adult female fishes were used for the experiment. The animals were divided into a control group (C), fed with unsaturated fatty acid diet, and a saturated fatty acid group (Sat). They received food three times a day, during the 11-week period. The results showed that animals in the Sat group had increased body weight, with a difference relative to the C group, from the third week of diet until the end of the experiment. At the end of the last week, the Sat group had a body weight 32% higher (P=0.0182) than the body weight of the control group. The consumption of a diet rich in saturated fatty acids did not generate signs related to stress and anxiety in zebrafish. There was an increase in glycemia at T60 and T120, with a statistically significant difference between the two moments. Animals in the Sat group showed an increase (P=0.0086) in hepatic steatosis compared to animals in the control group. The results obtained on the relationship between diet and metabolic changes are fundamental to ensure the understanding and appropriate treatment of these problems.

Effect of Dietary Protein and Lipid Ratios on Zootechnical Performance and Body Composition of African Native Freshwater Prawn Macrobrachium macrobrachion (Herklots, 1851) Juveniles

Effect of Dietary Protein and Lipid Ratios on Zootechnical Performance and Body Composition of African Native Freshwater Prawn <i>Macrobrachium macrobrachion</i> (Herklots, 1851) Juveniles

Effects of Substituting Fish Meal by Chlorella Meal in Practical Diet on Growth, Feed Utilization, and Flesh Quality of Pacific White Shrimp (Penaeus vannamei)

This study investigated the effects of substituting fish meal (FM) in practical diet by chlorella meal on the growth, feed utilization, and flesh quality of Pacific white shrimp (Penaeus vannamei). First, a basal diet was prepared with 200 g/kg FM inclusion (FM‐20), and then chlorella meal was used to reduce FM inclusion to 150 g/kg (FM‐15), 100 g/kg (FM‐10), 50 g/kg (FM‐5), and 0 g/kg (FM‐0), corresponding to the replacement levels of 25%, 50%, 75%, and 100% of dietary FM, respectively. Shrimp (1.37 ± 0.10 g) were fed with the five isonitrogenous and isolipidic diets for 56 days. No significant difference was observed in feed conversion ratio (FCR) and weight gain (WG) between FM‐20 and FM‐15 group (P &gt; 0.05), but when chlorella meal substituted 50% of dietary FM, WG, protein and lipid retention, and n‐3/n‐6 PUFAs in flesh were significantly reduced with significant increase in FCR (P &lt; 0.05). Survival, feed intake, meat yield, apparent digestibility coefficient of crude protein, dry matter, and flesh shear force showed no significant difference between FM‐20 and substituted groups (P &gt; 0.05). When dietary FM was totally substituted by chlorella meal, the body yellowness and redness and essential amino acid content in flesh, including Lys and Met, were significantly reduced (P &lt; 0.05). No significant differences were found in flesh total collagen, crude lipid, crude protein, serum biochemical indexes, flesh texture profiles (hardness, springiness, etc.), water holding capacity, antioxidant capacity, fatty acid, free amino acid composition, and muscle fiber density among the five treatments (P &gt; 0.05). To sum up, in a practical diet with 200 g/kg FM inclusion, chlorella meal successfully replaced 25% of dietary FM without adverse impacts on the growth and feed utilization, and the substitution of 75% of dietary FM did not negatively affect the flesh quality of Pacific white shrimp.

Effects of different traditional and commercial feed on growth, survival and proximate composition of Rohu (Labeo rohita) reared in the semi-intensive composite culture system.

This study was investigated to assess the effects of different traditional and commercial aqua feed on proximate composition, growth performance and survival rate of Labeo rohita reared in the composite semi-intensive culture system. The aqua feeds of various companies (AMG, Supreme, Aqua, Star Floating, Hi-Pro and Punjab feed) used as commercial feed. Farm made feeds were maize gluten and rice polish. For confidentiality, these feeds were randomly given code labels T1, T2, T3, T4, T5, T6, T7 and T8 which were only known to investigating staffs. There were two replicates for each treatment. In this experiment, higher growth rate was observed in T3 as compared to other treatments. Lesser weight gain was observed in the T1 ( 270.30 ± 0.5 ). The maximum body length ( 19.25 ± 2.19) was found in T3. Similarly, the minimum body length (5.97 ± 2.94) was seen in T2. FCR ratio (2.36 ± 0.01 ) was recorded in T3. Simultaneously, FCR (1.86 ± 0.002 ) was also recorded in T4 that is the perfect ratio for farmers. Higher SGR was noted in T3 (1.62 ± 0.05 ). Overall, T4 showed lesser SGR (1.05 ± 0.001 ). T4 showed the higher crude protein ( 28.66 ± 0.24 % ). In the body composition higher level of fat content was recorded in T3 ( 5.46 ± 0.33 %). These outcomes also proved that the rise in the dietary protein level and lipid content can improve the fish's body crude fats and protein level. Thus, based on growth performance, survival and proximate composition. It is concluded that T3 and T4 may be recommended for commercial culture of L. rohita.

Influence of lipid oxidation on the digestive efficiency of Antarctic krill oil: insights from a simulated gastrointestinal digestion model

Lipid oxidation profoundly impacts its digestibility, a topic that has been predominantly investigated in triglyceride (TAG)- based dietary lipids. However, there is a dearth of similar research on lipids with...

Effects of replacement of dietary fish oil with plant oil on growth performance and fatty acid composition of spinefoot rabbitfish, Siganus rivulatus.

A 95-day feeding study was carried out to evaluate the impact of complete replacement of fish oil by plant oils in the growth performance, feed consumption fatty acid and body composition of juvenile rabbitfish, Siganus rivulatus. There were four treatments i.e., A (fish oil diet), (linseed oil diet), C (soybean meal oil diet) and D (sunflower oil diet). The experimental trial was conducted in twelve 1.5-m3 fiber glass tanks (n=3). Spinefoot rabbitfish juveniles had an average initial weight of 0.948 g ± 0.124 g and they were stocked at 50 fish per tank. Fish fed diet A showed significantly better growth rate, final body weight, and total body weight than fish fed on the other diets. Moreover, the best FCR was observed for diet A followed by diet C and diets B and D had the worst FCR. Fish body composition for crude protein, dry matter, ashes and gross energy at the end of the trial had not differed between the treatments. The highest polyunsaturated fatty acids (PUFA) was found in fish fed diet A followed in decreasing order by diets D, B, and C. Fish oil is a better dietary lipid source for Spinefoot rabbitfish juveniles, Siganus rivulatus, than plant oils. Among plant oils, soybean oil was better than linseed oil and sunflower oil as the main dietary fat source.

Lipid Storage, Lipolysis, and Lipotoxicity in Obesity.

The ratio of free fatty acid (FFA) turnover decreases significantly with the expansion of white adipose tissue. Adipose tissue and dietary saturated fatty acid levels significantly correlate with an increase in fat cell size and number. The G0/G1 switch gene 2 increases lipid content in adipocytes and promotes adipocyte hypertrophy through the restriction of triglyceride (triacylglycerol: TAG) turnover. Hypoxia in obese adipose tissue due to hypertrophic adipocytes results in excess deposition of extracellular matrix (ECM) components. Cluster of differentiation (CD) 44, as the main receptor of the extracellular matrix component regulates cell-cell and cell-matrix interactions including diet-induced insulin resistance. Excess TAGs, sterols, and sterol esters are surrounded by the phospholipid monolayer surface and form lipid droplets (LDs). Once LDs are formed, they grow up because of the excessive amount of intracellular FFA stored and reach a final size. The ratio of FFA turnover/lipolysis decreases significantly with increases in the degree of obesity. Dysfunctional adipose tissue is unable to expand further to store excess dietary lipids, increased fluxes of plasma FFAs lead to ectopic fatty acid deposition and lipotoxicity. Reduced neo-adipogenesis and dysfunctional lipid-overloaded adipocytes are hallmarks of hypertrophic obesity linked to insulin resistance. Obesity-associated adipocyte death exhibits feature of necrosis-like programmed cell death. Adipocyte death is a prerequisite for the transition from hypertrophic to hyperplastic obesity. Increased adipocyte number in obesity has life-long effects on white adipose tissue mass. The positive correlation between the adipose tissue volume and magnetic resonance imaging proton density fat fraction estimation is used for characterization of the obesity phenotype, as well as the risk stratification and selection of appropriate treatment strategies. In obese patients with type 2 diabetes, visceral adipocytes exposed to chronic/intermittent hyperglycemia develop a new microRNAs' (miRNAs') expression pattern. Visceral preadipocytes memorize the effect of hyperglycemia via changes in miRNAs' expression profile and contribute to the progression of diabetic phenotype. Nonsteroidal anti-inflammatory drugs, metformin, and statins can be beneficial in treating the local or systemic consequences of white adipose tissue inflammation. Rapamycin inhibits leptin-induced LD formation. Collectively, in this chapter, the concept of adipose tissue remodeling in response to adipocyte death or adipogenesis, and the complexity of LD interactions with the other cellular organelles are reviewed. Furthermore, clinical perspective of fat cell turnover in obesity is also debated.

Comparison of the Catabolic Rates of Linoleic and Oleic Acid Hydroperoxides Using 13CO2 Expired from Mice.

Unsaturated fatty acids, such as oleic and linoleic acids, are easily oxidized by exposure to temperature and light in the presence of air to form unsaturated fatty acid hydroperoxides as primary oxidation products. However, the catabolic rates of unsaturated fatty acid hydroperoxides in the human body remain unknown. In this study, ethyl esters of 13C-labeled linoleic acid (*C18:2-EE) and oleic acid (*C18:1-EE) and their hydroperoxides (*C18:2-EE-OOH and *C18:1-EE-OOH, respectively) prepared by the photo-oxidation of *C18:2-EE and *C18:1-EE, respectively, were administered to mice and their catabolic rates were determined by measuring the expired 13CO2 levels. *C18:2-EE-OOH and *C18:1-EE-OOH were β-oxidized faster than *C18:2-EE and *C18:1-EE, respectively. Notably, rapid β-oxidation of *C18:2-EE-OOH and *C18:1-EE-OOH was similar to that of medium-chain fatty acids, such as octanoic acid. Then, degradation products of C18:2-EE-OOH and C18:1-EE-OOH were analyzed under gastric conditions by gas chromatography/mass spectrometry. Major decomposition products of C18:2-EE-OOH and C18:1-EE-OOH were medium-chain compounds, such as octanoic acid ethyl ester, 9-oxo-nonanoic acid ethyl ester, and 10-oxo-8-decenoic acid ethyl esters, indicating that C18:2-EE-OOH and C18:1-EE-OOH isomers formed during photo-oxidation were decomposed under acidic conditions. These findings support previous reports that dietary lipid hydroperoxides are not absorbed into the intestine as lipid hydroperoxides but as degradation products. This is the first study to suggest that dietary lipid hydroperoxides decompose during gastric digestion to form medium-chain compounds that are directly absorbed into the liver via the portal vein and rapidly catabolized via β-oxidation.

Gut-brain communication mediates the impact of dietary lipids on cognitive capacity.

Cognitive impairment, as a prevalent symptom of nervous system disorders, poses one of the most challenging aspects in the management of brain diseases. Lipids present in the cell membranes of all neurons within the brain and dietary lipids can regulate the cognition and memory function. In recent years, the advancements in gut microbiome research have enabled the exploration of dietary lipids targeting the gut-brain axis as a strategy for regulating cognition. This present review provides an in-depth overview of how lipids modulate cognition via the gut-brain axis depending on metabolic, immune, neural and endocrine pathways. It also comprehensively analyzes the effects of diverse lipids on the gut microbiota and intestinal barrier function, thereby affecting the central nervous system and cognitive capacity. Moreover, comparative analysis of the positive and negative effects is presented between beneficial and detrimental lipids. The former encompass monounsaturated fatty acids, short-chain fatty acids, omega-3 polyunsaturated fatty acids, phospholipids, phytosterols, fungal sterols and bioactive lipid-soluble vitamins, as well as lipid-derived gut metabolites, whereas the latter (detrimental lipids) include medium- or long-chain fatty acids, excessive proportions of n-6 polyunsaturated fatty acids, industrial trans fatty acids, and zoosterols. To sum up, the focus of this review is on how gut-brain communication mediates the impact of dietary lipids on cognitive capacity, providing a novel theoretical foundation for promoting brain cognitive health and scientific lipid consumption patterns.

Host-gut microbiota derived secondary metabolite mediated regulation of Wnt/β-catenin pathway: a potential therapeutic axis in IBD and CRC.

The intestinal tract encompasses one of the largest mucosal surfaces with a well-structured layer of intestinal epithelial cells supported by a network of underlying lamina propria immune cells maintaining barrier integrity. The commensal microflora in this environment is a major contributor to such functional outcomes due to its prominent role in the production of secondary metabolites. Of the several known metabolites of gut microbial origin, such as Short Chain Fatty Acids (SCFAs), amino acid derivatives, etc., secondary bile acids (BAs) are also shown to exhibit pleiotropic effects maintaining gut homeostasis in addition to their canonical role in dietary lipid digestion. However, dysbiosis in the intestine causes an imbalance in microbial diversity, resulting in alterations in the functionally effective concentration of these secondary metabolites, including BAs. This often leads to aberrant activation of the underlying lamina propria immune cells and associated signaling pathways, causing intestinal inflammation. Sustained activation of these signaling pathways drives unregulated cell proliferation and, when coupled with genotoxic stress, promotes tumorigenesis. Here, we aimed to discuss the role of secondary metabolites along with BAs in maintaining immune-gut homeostasis and regulation of inflammation-driven tumorigenesis with emphasis on the classical Wnt/β-Catenin signaling pathway in colon cancer.

Deletion of RAMP1 Signaling Enhances Diet-induced Obesity and Fat Absorption via Intestinal Lacteals in Mice.

Intestinal lymphatic vessels (lacteals) play a critical role in the absorption and transport of dietary lipids into the circulation. Calcitonin gene-related peptide and receptor activity-modifying protein 1 (RAMP1) are involved in lymphatic vessel growth. This study aimed to examine the role of RAMP1 signaling in lacteal morphology and function in response to a high-fat diet (HFD). RAMP1 deficient (RAMP1-/-) or wild-type (WT) mice were fed a normal diet (ND) or HFD for 8 weeks. RAMP1-/- mice fed a HFD had increased body weights compared to WT mice fed a HFD, which was associated with high levels of total cholesterol, triglycerides, and glucose. HFD-fed RAMP1-/- mice had shorter and wider lacteals than HFD-fed WT mice. HFD-fed RAMP1-/- mice had lower levels of lymphatic endothelial cell gene markers including vascular endothelial growth factor receptor 3 (VEGFR3) and lymphatic vascular growth factor VEGF-C than HFD-fed WT mice. The concentration of an absorbed lipid tracer in HFD-fed RAMP1-/- mice was higher than that in HFD-fed WT mice. The zipper-like continuous junctions were predominant in HFD-fed WT mice, while the button-like discontinuous junctions were predominant in HFD-fed RAMP1-/- mice. Deletion of RAMP1 signaling suppressed lacteal growth and VEGF-C/VEGFR3 expression but accelerated the uptake and transport of dietary fats through discontinuous junctions of lacteals, leading to excessive obesity. Specific activation of RAMP1 signaling may represent a target for the therapeutic management of diet-induced obesity.

Exploring the Transmembrane Behaviors of Dietary Flavonoids under Intestinal Digestive Products of Different Lipids: Insights into the Structure-Activity Relationship In Vitro.

This study aimed to investigate the transmembrane transport behavior and structure-activity relationships of various dietary flavonoids in the presence of dietary lipids derived from different sources in vitro. Results revealed that the digestion products of soybean oil (SOED) and lard (LOED) augmented the apparent permeability coefficients of most dietary flavonoids, and SOED exhibited higher transport compared with LOED. The structural properties of flavonoids and the potential interactions between fatty acids in these digestion products and flavonoids may influence the outcomes. 3D quantitative structure-activity relationship analyses revealed that incorporating small-volume groups at position 8 of the A-ring augmented the transmembrane transfer of flavonoids in the LOED system compared with the control group. By contrast, the integration of hydrophobic groups at position 5 of the A-ring and hydrogen bonding acceptor groups at position 6 of the A-ring enhanced the transmembrane transportation of flavonoids in the SOED system. Molecular dynamics simulations revealed that the SOED system may facilitate the interactions with flavonoids to form more stable and compact fatty acid-flavonoid complexes compared to the LOED system. These findings may provide valuable insights into flavonoid absorption to facilitate the development and utilization of functional foods or dietary supplements based on dietary flavonoids.

Evaluation of the effects of diets containing different lipid levels for juvenile yellowfin seabream Acanthopagrus latus

This study evaluated the effect of dietary lipid levels on growth, body composition, amino acid and fatty acid profile, and nutrient utilization of juvenile yellowfin seabream (Acanthopagrus latus). Six diets with different crude lipid levels at 7% (CL7), 9% (CL9), 11% (CL11), 13% (CL13), 15% (CL15), and 17% (CL17) were designed, and each diet was fed to 4 cages (50 fish per cage; 19.00 ± 0.01 g per fish) for sixteen weeks. Results indicated that weight gain (WG) and specific growth rate (SGR) were highest at 13% dietary lipid level, while feed conversion ratio (FCR) was lowest (P < 0.05). Intraperitoneal fat ratio (IPF) increased with increasing dietary lipid level from 7% to 17%. The lipid efficiency ratio (LER), lipid retention (LR), and nitrogen excretion (NE) decreased significantly with increasing dietary lipid level (P < 0.05). Crude protein and lipid of the whole body decreased or increased with increasing dietary lipid level, respectively (P < 0.05). The dorsal muscle and liver lipid content significantly increased with increasing dietary lipid (P < 0.05). With the dietary lipid increasing, total fatty acid content was significantly increased (P < 0.05). Results about the fatty acid profile of the whole body indicated that the proportions of C14:0, C16:1, C20:4, C20:5, and C20:6 were significantly decreased with increased dietary lipid level (P < 0.05). In contrast, the proportions of C18:0, C18:1, and C22:1 were increased with increased dietary lipid level (P < 0.05). The retention of fatty acids was decreased with increasing dietary lipid (P < 0.05). Form a nutritional, environmental, and economic point of view, 13% dietary crude lipid was recommended. Excess dietary lipid levels in diets negatively affect the structure of the liver, leading to lipid accumulation and inflammation development.

Insights Into Inflammatory Bowel Disease and Effects of Dietary Fatty Acid Intake With a Focus on Polyunsaturated Fatty Acids Using Preclinical Models.

While the aetiology of inflammatory bowel disease (IBD) has been linked to genetic susceptibility coupled with environmental factors, the underlying molecular mechanisms remain unclear. Among the environmental factors, diet and the gut microbiota have been implicated as drivers of immune dysregulation in IBD. Indeed, epidemiologic studies have highlighted that the increase in incidence of IBD parallels the increase in dietary intake of omega-6 (n-6) polyunsaturated fatty acids (PUFAs) and the change in balance of intake of n-6 to n-3 fatty acids. Experimental evidence suggests that the increase in n-6 PUFA intake increases cell membrane arachidonic acid, which is accompanied by the production of pro-inflammatory mediators as well as increased oxidative stress; together, this contributes to the development of chronic inflammation. However, it is also increasingly clear that some of the n-6 PUFA-derived mediators exert beneficial effects depending on the settings and timing of ingestion. In contrast to n-6, when n-3 PUFA eicosapentaenoic acid and docosahexaenoic acid are incorporated into the cell membrane and are metabolized into less pro-inflammatory eicosanoids, as well as strong specialized pro-resolving mediators, which play a role in inflammation cessation. With a focus on preclinical models, we explore the relationship between dietary lipid, the gut microbiome, and intestinal inflammation.

Effects of Different Aquafeed Sources on Growth Performance, Oxidative Capacity, and Fatty Acid Profile of Three Carps Reared in the Semi-Intensive Composite Culture System.

The current experiment is designed to evaluate the effect of different aquafeeds (farm-made versus commercial) on growth, body composition, oxidative capacity, and fatty acid profile in the semi-intensive composite culture system. For this, 1,100 fingerlings/acre having initial body weight and length, Labeo rohita (61.34 g, 171 mm), Catla catla (71.45 g, 181 mm), and Cyprinus carpio (30.80 g, 91 mm) were randomly distributed to 16 ponds and randomly fed on eight different diets (n = 2 pond/diet) in a completely randomized research design. Aquafeed were farm-based diets (D1-D2) and commercial aquafeed (D3-D8). The farm-made diets contained various crude protein levels of maize gluten (24.9%) and rice polish (7.3%), whereas commercial diets were procured from commercial feed plants (AMG, Supreme, Aqua, Star Floating, Hi-Pro, and Punjab feed). The growth performance of carps (L. rohita and C. catla) was significantly improved (p < 0.05) by feeding D3 as compared to other diets. Similarly, white blood cell concentration was greater (p < 0.05) in all species fed by D3 than in those fed on D7, D8, D5, D6, D1, and D2 fed groups, respectively. Alanine transaminase, aspartate transaminase, and alanine phosphatase activities were significantly lower (p < 0.05) in the D3-fed L. rohita, C. catla, and C. carpio compared with those fed on the rest of the treatments. The activities of glutathione peroxidase and superoxide dismutase were also higher (p < 0.05) for the D3 fed L. rohita, C. catla, and C. carpio than those fed on the rest diets. The groups fed on D3 and D4 had greater (p < 0.05) concentrations of myristic (14), palmitic acid (16), and stearic (18) acids than those fed on the rest of the commercial diets. However, meat chemical composition was similar (p > 0.05) across the treatments. These results also prove that the increase in the dietary protein level and lipid content can improve the fish's body's crude protein and fat levels. Feeding D3 improved the production performance, oxidative status, and fatty acid profile in composite major carps culture systems. Thus, based on growth, survival, and body composition, it is concluded that D3 and D4 may be recommended for a commercial culture of major carps. Dietary treatments had no significant impact (p > 0.05) on water's physical-chemical properties. Calcium content and alkalinity varied (p < 0.05), with D5 showing the lowest calcium and the highest alkalinity.

Lipid supplementation with macadamia by-product reduces methane emissions by sheep

Macadamia cake (MC) is a waste product from the macadamia nut industry with high nutritional value for animal nutrition. It has the potential to modify rumen fermentation, increase the efficiency of rumen microorganisms, and reduce methanogenesis. This study aimed to evaluate how the dietary lipid supplementation with MC modulates the methane (CH4) emission and nutrients digestibility of finishing lambs. Thirty-one lambs, approximately 90 days old and mean initial body weight of 26 ± 3.4 kg, were allocated to individual metabolic cages and subjected to in vivo digestibility assays for 24 days (17 days of adaption and 7 days of data collection). The four treatments included a Control group with no MC addition, and three groups with varying amounts of MC inclusion in the diet: 4.5%, 8.5%, and 14% on a dry matter basis. The ruminal content was collected individually at the last day of the digestibility assay 2 to 3 h after the morning feed, to measure pH, protozoan count, and short-chain fatty acids. The animals were then moved to semi-open respirometry chambers for the in vivo measurement of CH4 emission. A completely randomized design was used in the study assuming MC intake (MCI) as fixed effect and each animal as random effect. The variables were submitted to tests of normality and homoscedasticity. The data was submitted to analysis of variance at a 5% significance level using the F test (P < 0.05) and polynomial regression analysis. Pearson’s correlation coefficient test was also applied to all variables. Daily dry matter intake or apparent total tract digestibility parameters were not affected by MCI (P > 0.05), while ether extract and gross energy intake showed the widest range of values, from 0.01 to 0.09 (kg/day) and 9.3 to 22.5 (MJ/day), respectively, increasing (P > 0.05) according to MCI. In addition, total digestible nutrients increased linearly with MC supplementation (P = 0.037). MCI had a significant suppressive effect on enteric CH4 production from 21.9 to 8.6 (L/day) (P < 0.05) and protozoan count (P < 0.001) from 291875 to 69500 (n/mL), while a cubic (P = 0.03) and linear (P = 0.05) effect was observed for ammonia nitrogen and butyric acid, respectively. Macadamia cake may be used as an ingredient in sheep diets and its inclusion up to 14% has shown promise in reducing daily emissions of enteric CH4 without compromising nutrient digestibility and ruminal fermentation, in addition to contributing to reducing the environmental impact by avoiding the disposal of this industrial by-product.

Antidiabetic efficacy of sea fish oil in ameliorating hyperglycaemia by enhancing FFAR1, GLP-1 and inhibiting DPP-4 signalling in the pancreatic tissues of high lipid diet and streptozotocin-induced type 2 diabetic rats

Eicosapentaenoic acid and docosahexaenoic acid are n-3 fatty acids that are highly available in sea-fishes. Many studies have revealed that n-3 fatty acids play antidiabetic activity. In this study antidiabetic activity of the three sea fishes oils, ‘volavetki’ (Panna microdon, Bleeker 1849), ‘ruli’ (Coilia dussumieri, Valenciennes 1848), and ‘tapra’ (Opisthopterus tardoore, Cuvier 1829), as well as three fresh-water fishes oils, ‘bata’ (Labeo bata, Hamilton 1822), ‘folui’ (Opisthopterus tardoore, Cuvier 1829), and ‘mourala’ (Amblypharyngodon mola, Hamilton 1822) evaluated high lipid diet (HLD) and STZ-induced type 2 diabetes mellitus (T2DM) rats. The GC-MS analysis revealed high n-3 fatty acid content in volavetki oil. Supplementation of sea-fish oils and antidiabetic effect was monitored by fasting plasma blood glucose and HbA1c. Also, insulin, c-peptide, glucagon-like peptide-1, dipeptidyl peptidase-4, free fatty acid receptor 1, glucokinase, glucose-6 phosphatase, superoxide dismutase, glutathione peroxidase, catalase, malondialdehyde, plasma total cholesterol, low density lipoprotein, triglycerides, high density lipoprotein, c-reactive protein, total protein, alkaline phosphatase, and histopathology of pancreatic tissues were evaluated. Out of six fish oils, oral supplementation with volavetki oil resulted in significant reduction of plasma blood glucose, HbA1c of T2DM rat. All other parameters in T2DM rats were returned to near normally by treatment of volavetki oil. These findings strongly indicate that volavetki oil possess antidiabetic activity.

An Intestinal FXR Agonist Mitigates Dysbiosis, Intestinal Tight Junctions, and Inflammation in High-Fat Diet-Fed Mice.

To analyze the effects of fexaramine (FEX), as an intestinal FXR agonist, on the modulation of the intestinal microbiota and ileum of mice fed a high-fat (HF) diet. Three-month-old C57Bl/6 male mice are divided into two groups and received a control (C, 10% of energy from lipids) or HF (50% of energy from lipids) diet for 12 weeks. They are subdivided into the C, C+FEX, HF, and HF+FEX groups. FEX is administered (FEX-5mgkg-1 ) via orogastric gavage for three weeks. Body mass (BM), glucose metabolism, qPCR16SrRNA gene expression, and ileum gene expression, bile acids (BAs), tight junctions (TJs), and incretin are analyzed. FEX reduces BM and glucose intolerance, reduces plasma lipid concentrations and the Firmicutes/Bacteroidetes ratio, increases the Lactobacillus sp. and Prevotella sp. abundance, and reduces the Escherichia coli abundance. Consequently, the ileal gene expression of Fxr-Fgf15, Tgr5-Glp1, and Cldn-Ocldn-Zo1 is increased, and Tlr4-Il6-Il1beta is decreased. FEX stimulates intestinal FXR and improves dysbiosis, intestinal TJs, and the release of incretins, mitigating glucose intolerance and BM increases induced by an HF diet. However, FEX results in glucose intolerance, insulin resistance, and reduces intestinal TJs in a control group, thus demonstrating limitations to this dietary model.

Food Polyphenols as Preventive Medicine.

Reactive oxygen species (ROS) are the initiators in foods and in the stomach of oxidized dietary lipids, proteins, and lipid-oxidation end-products (ALEs), inducing in humans the development of several chronic diseases and cancer. Epidemiological, human clinical and animal studies supported the role of dietary polyphenols and derivatives in prevention of development of such chronic diseases. There is much evidence that polyphenols/derivatives at the right timing and concentration, which is critical, acts mostly in the aerobic stomach and generally in the gastrointestinal tract as reducing agents, scavengers of free radicals, trappers of reactive carbonyls, modulators of enzyme activity, generators of beneficial gut microbiota and effectors of cellular signaling. In the blood system, at low concentration, they act as generators of electrophiles and low concentration of H2O2, acting mostly as cellular signaling, activating the PI3K/Akt-mediated Nrf2/eNOS pathways and inhibiting the inflammatory transcription factor NF-κB, inducing the cells, organs and organism for eustress, adaptation and surviving.