Triacylglycerol Concentrations Research Articles

Transcriptomic and lipid profiling analysis reveals a functional interplay between testosterone and growth hormone in hypothyroid liver.

Preclinical and clinical studies suggest that hypothyroidism might cause hepatic endocrine and metabolic disturbances with features that mimic deficiencies of testosterone and/or GH. The absence of physiological interactions between testosterone and GH can be linked to male differentiated liver diseases. Testosterone plays relevant physiological effects on somatotropic-liver axis and liver composition and the liver is a primary organ of interactions between testosterone and GH. However, testosterone exerts many effects on liver through complex and poorly understood mechanisms. Testosterone impacts liver functions by binding to the Androgen Receptor, and, indirectly, through its conversion to estradiol, and cooperation with GH. However, the role of testosterone, and its interaction with GH, in the hypothyroid liver, remains unclear. In the present work, the effects of testosterone, and how they impact on GH-regulated whole transcriptome and lipid composition in the liver, were studied in the context of adult hypothyroid-orchiectomized rats. Testosterone replacement positively modulated somatotropic-liver axis and impacted liver transcriptome involved in lipid and glucose metabolism. In addition, testosterone enhanced the effects of GH on the transcriptome linked to lipid biosynthesis, oxidation-reduction, and metabolism of unsaturated and long-chain fatty acids (FA). However, testosterone decreased the hepatic content of cholesterol esters and triacylglycerols and increased fatty acids whereas GH increased neutral lipids and decreased polar lipids. Biological network analysis of the effects of testosterone on GH-regulated transcriptome confirmed a close connection with crucial proteins involved in steroid and fatty acid metabolism. Taken together, this comprehensive analysis of gene expression and lipid profiling in hypothyroid male liver reveals a functional interplay between testosterone and pulsed GH administration.

The Ameliorating Effects of n-3 Polyunsaturated Fatty Acids on Liver Steatosis Induced by a High-Fat Methionine Choline-Deficient Diet in Mice.

The pathogenesis of non-alcoholic fatty liver disease (NAFLD) is associated with abnormalities of liver lipid metabolism. On the contrary, a diet enriched with n-3 polyunsaturated fatty acids (n-3-PUFAs) has been reported to ameliorate the progression of NAFLD. The aim of our study was to investigate the impact of dietary n-3-PUFA enrichment on the development of NAFLD and liver lipidome. Mice were fed for 6 weeks either a high-fat methionine choline-deficient diet (MCD) or standard chow with or without n-3-PUFAs. Liver histology, serum biochemistry, detailed plasma and liver lipidomic analyses, and genome-wide transcriptome analysis were performed. Mice fed an MCD developed histopathological changes characteristic of NAFLD, and these changes were ameliorated with n-3-PUFAs. Simultaneously, n-3-PUFAs decreased serum triacylglycerol and cholesterol concentrations as well as ALT and AST activities. N-3-PUFAs decreased serum concentrations of saturated and monounsaturated free fatty acids (FAs), while increasing serum concentrations of long-chain PUFAs. Furthermore, in the liver, the MCD significantly increased the hepatic triacylglycerol content, while the administration of n-3-PUFAs eliminated this effect. Administration of n-3-PUFAs led to significant beneficial differences in gene expression within biosynthetic pathways of cholesterol, FAs, and pro-inflammatory cytokines (IL-1 and TNF-α). To conclude, n-3-PUFA supplementation appears to represent a promising nutraceutical approach for the restoration of abnormalities in liver lipid metabolism and the prevention and treatment of NAFLD.

Microalgae suspension as a source of n-3 long-chain PUFA in feed for Atlantic Salmon (Salmo salar L) – Technical constraints and nutritional quality

The aim of this research was to study possible inclusion levels of AlgaPrime™ DHA LS microalgae (Schizochytrium sp.) plant oil suspension in feed mixes prior to extrusion and in the post drying vacuum coating step and evaluate microalgae digestibility in Atlantic salmon (Salmo salar L). In the technical evaluation, physical quality, expansion, and microstructure parameters were studied for AlgaPrime™ DHA LS inclusion in fishmeal and plant-based diets prior to extrusion. A target lipid level of 361 g/kg DM was achieved for all feeds. High physical quality and water stability were measured and mixture design models with R2 in the range of 0.950 to 0.999 (P < 0.001) were established for specific mechanical energy (SME), apparent dough viscosity in the extruder die (Vdie), expansion, and microstructure parameters. Addition of AlgaPrime™ DHA LS resulted in a feed mix lipid level in the range of 27 to 204 g/kg and was the main contributor for the observed variation in this study. Commercially, the most interesting feed was the centroid point with a feed mix lipid content of 92 g/kg. This equals an AlgaPrime™ DHA LS content of 48 g/kg in the final feed. Alternatively, the AlgaPrime™ DHA LS can be added in the vacuum coating process. In this study the pellet pores size distribution allowed high amount of microalgae suspension to be absorbed (50% of total oil) with no significant impact on oil leakage. Based on the findings in the technical trial, 4 diets were produced for the fish experiment; 1) control feed with a 1:1 fish oil and rapeseed oil mixture, 2) a feed where the oil mixture was partly replaced by 100 g/kg AlgaPrime™ DHA LS prior to extrusion, 3) a feed where 100 g/kg of oil mixture were replaced in the vacuum coating step by 100 g/kg AlgaPrime™ DHA LS and 4) where 100 g/kg oil mixture was replaced both prior to extrusion and in the vacuum coating step by AlgaPrime™ DHA LS. All diets showed high nutrient digestibility in Atlantic salmon, also for the saturated fatty acids. This documents no need for extra cell wall rupture for the microalgae suspension prior to extrusion or vacuum coating. Lower content of tri-saturated triacylglycerols than reported in previous Schizochytrium biomasses have limited the negative effects on the digestibility of saturated fatty acids in Atlantic salmon.

Lipid accumulation mechanism of Amphora coffeaeformis under nitrogen deprivation and its application as a feed additive in Carassius auratus aquaculture

BackgroundAmphora coffeaeformis, a unicellular diatom, can significantly accumulate lipids under nitrogen (N) limitation. However, the molecular mechanism underlying lipid accumulation in A. coffeaeformis remains unknown and its application development is lagging.ResultsThis work analyzed the lipid composition of A. coffeaeformis under N deprivation and investigated its mechanism underlying lipid accumulation using RNA-seq. The results showed that the total lipid content of A. coffeaeformis increased from 28.22 to 44.05% after 5 days of N deprivation, while the neutral lipid triacylglycerol (TAG) content increased from 10.41 to 25.21%. The transcriptional profile showed that N deprivation induced wide-ranging reprogramming of regulation and that most physiological activities were repressed, while the upregulation of glycerol-3-phosphate acyltransferase directly determined TAG accumulation. Moreover, we explored the effect of A. coffeaeformis as a food additive on the lipid composition of crucian carp. The results showed that the contents of unsaturated fatty acids in the meat of fish supplemented with A. coffeaeformis were significantly increased, indicating its potential application in animal nutrition for improving meat quality indicators.ConclusionThe findings shed light on the molecular mechanisms of neutral lipid accumulation and revealed the key genes involved in lipid metabolism in A. coffeaeformis. Moreover, we also confirmed that A. coffeaeformis can be used as feed additive for improving the lipid composition of crucian carp meat, which provided evidence for the biotechnology application of this high-oil microalgae.

Two plastidial lysophosphatidic acid acyltransferases differentially mediate the biosynthesis of membrane lipids and triacylglycerols in Phaeodactylum tricornutum.

Lysophosphatidic acid acyltransferases (LPAATs) catalyze the formation of phosphatidic acid (PA), a central metabolite in both prokaryotic and eukaryotic organisms for glycerolipid biosynthesis. Phaeodactylum tricornutum contains at least two plastid-localized LPAATs (ptATS2a and ptATS2b), but their roles in lipid synthesis remain unknown. Both ptATS2a and ptATS2b could complement the high temperature sensitivity of the bacterial plsC mutant deficient in LPAAT. In vitro enzyme assays showed that they prefer lysophosphatidic acid over other lysophospholipids. ptATS2a is localized in the plastid inner envelope membrane and CRISPR/Cas9-generated ptATS2a mutants showed compromised cell growth, significantly changed plastid and extra-plastidial membrane lipids at nitrogen-replete condition and reduced triacylglycerols (TAGs) under nitrogen-depleted condition. ptATS2b is localized in thylakoid membranes and its knockout led to reduced growth rate and TAG content but slightly altered molecular composition of membrane lipids. The changes in glycerolipid profiles are consistent with the role of both LPAATs in the sn-2 acylation of sn-1-acyl-glycerol-3-phosphate substrates harboring 20:5 at the sn-1 position. Our findings suggest that both LPAATs are important for membrane lipids and TAG biosynthesis in P. tricornutum and further highlight that 20:5-Lyso-PA is likely involved in the massive import of 20:5 back to the plastid to feed plastid glycerolipid syntheses.

Influencing factors of post-transplantation diabetes mellitus in kidney transplant recipients and establishment of a risk prediction model.

The aim was to explore the influencing factors of post-trans-plantation diabetes mellitus (PTDM) in kidney transplant recipients and to es-tablish a risk prediction model. A retrospective analysis was performed on the clinical data of 408 patients subjected to kidney transplantation from May 2015 to March 2022. With the simple random sampling method, they were divided into a training set (n=306) and a test set (n=102) at a ratio of 3:1. According to the occurrence of PTDM, the training set was further classified into PTDM and non-PTDM groups. The influencing factors of PTDM were identified by least absolute shrinkage and selection operator and multivariate logistic regression analysis. A nomogram prediction model was constructed and validated. Non-PT-DM and PTDM groups had significantly different preoperative body mass index (BMI), family history of diabetes mellitus, 2-h preoperative and postprandial blood glucose, 2-hpreoperative and postprandial peptide index, postoperative hypomagnesemia, whole blood concentration of tacrolimus, triacylglycerol, glycated albumin and fasting blood glucose (P&lt;0.05). BMI, family history of diabetes mellitus, 2-h preoperative and postprandial blood glucose, and post-operative whole blood tacrolimus concentration were independent risk factors for PTDM. In contrast, the 2-h preoperative and postprandial peptide index was an independent protective factor (P&lt;0.05). The incidence of PTDM in patients receiving kidney transplantation correlates with the family history of diabetes mellitus, preoperative BMI, 2-h postprandial blood glucose, 2-h postprandial peptide index, and postoperative whole blood tacrolimus concentration.

Soybean LEAFY COTYLEDON 1: A Key Target for Genetic Enhancement of Oil Biosynthesis

Soybean is an important oilseed crop that is used as a feed for livestock and has several industrial uses. Lipid biosynthesis and accumulation primarily occur during seed development in plants. This process is regulated by several transcription factors and interconnected biochemical pathways. This study investigated the role of glycine max LEAFY COTYLEDON 1 (GmLEC1) in soybean seed development and the accumulation of storage reserves. The overexpression of GmLEC1 significantly increased the amount of triacylglycerol (TAG) in transgenic Arabidopsis seeds compared to the wild-type and an atlec1 mutant. Similarly, the high expression of GmLEC1 led to a 12% increase in TAG content in transgenic soybean hairy roots compared to the control. GmLEC1 also altered the fatty acid composition in transgenic Arabidopsis seeds and soybean hairy roots. Additionally, the overexpression of GmLEC1 resulted in a reduction in starch accumulation in seeds and vegetative tissues, as well as changes in cotyledon and seed morphology. The cotyledons of the atlec1 mutant displayed abnormal trichome development, and the seeds were smaller and less tolerant to desiccation. A complementation assay in Arabidopsis restored normal cotyledon phenotype and seed size. The main downstream targets of LEC1 are GL2 and WRI1, which were found to participate in fatty acid biosynthesis and trichome formation through the regulation of phytohormones and various transcription factors involved in seed development and maturation. The findings of this study suggest that GmLEC1 controls seed development and regulates the accumulation of seed storage compounds. Furthermore, these results demonstrate that GmLEC1 could be a reliable target for the genetic improvement of oil biosynthesis in soybean.

EPIGALLOCATECHIN-3-GALLATE ALLEVIATES METABOLIC DISORDERS IN RATS SIMULTANEOUSLY EXPOSED TO ROUND-THE-CLOCK LIGHTING AND KEPT ON HIGH-CALORIE CARBOHYDRATE-LIPID DIET

The aim of the study is to investigate the effect of epigallocatechin-3-gallate (EGCG) on the parameters of carbohydrate and lipid metabolism in the blood serum of rats exposed to round-the-clock lighting (RCL) and kept on high-calorie carbohydrate-lipid diet (HCCLD). The experiments were performed on 21 white Wistar rats weighing 210-250 g, divided into 3 groups. Animals in the first group (control) received a standard diet (energy value 2720 kcal/kg) and were exposed to an equally altered light and darkness periods. The rats of the second and third groups were under the constant round-the-clock light exposure and received HCCLD (4477 kcal/kg). In addition to the conditions in the second group, the test animals of the third group were administered EGCG daily through intragastric gavage in a dose of 40 mg/kg. An enzyme-linked immunosorbent assay kit for rat serum was used to assess insulin concentration. The concentration of serum glucose, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), very low-density lipoprotein (VLDL), and triacylglycerols (TAG) was determined by enzymatic methods using photometric equipment. Insulin resistance was assessed by the HOMA-IR (Homeostatic Model Assessment) index. With the administration of EGCG, the concentration of glucose and insulin in the blood serum decreased by 34.7% and 59.1%, respectively, compared to group 2, and the HOMA-IR was 61.5% lower than in the comparison group. The HDL content increased with the administration of EGCG in the experiment and was 91.3% higher compared to the findings in the group 2. Under these circumstances, the concentrations of VLDL and TAG in the blood serum were significantly lower by 37.5 and 37.1% than the respective values in the group 2. It can be suggested that the administration of the bioflavonoid epigallocatechin-3-gallate significantly alleviates metabolic disorders in rats simultaneously exposed to RCL and kept on HCCLD.

Intrauterine food restriction impairs the lipogenesis process in the mesenteric adipocytes from low-birth-weight rats into adulthood.

Intrauterine food restriction (IFR) during pregnancy is associated with low birth weight (LBW) and obesity in adulthood. It is known that white adipose tissue (WAT) plays critical metabolic and endocrine functions; however, this tissue's behavior before weight gain and obesity into adulthood is poorly studied. Thus, we evaluated the repercussions of IFR on the lipogenesis and lipolysis processes in the offspring and described the effects on WAT inflammatory cytokine production and secretion. We induced IFR by providing gestating rats with 50% of the necessary chow daily amount during all gestational periods. After birth, we monitored the offspring for 12 weeks. The capacity of isolated fat cells from mesenteric white adipose tissue (meWAT) to perform lipogenesis (14C-labeled glucose incorporation into lipids) and lipolysis (with or without isoproterenol) was assessed. The expression levels of genes linked to these processes were measured by real-time PCR. In parallel, Multiplex assays were conducted to analyze pro-inflammatory markers, such as IL-1, IL-6, and TNF-α, in the meWAT. Twelve-week-old LBW rats presented elevated serum triacylglycerol (TAG) content and attenuated lipogenesis and lipolysis compared to control animals. Inflammatory cytokine levels were increased in the meWAT of LBW rats, evidenced by augmented secretion by adipocytes and upregulated gene and protein expression by the tissue. However, there were no significant alterations in the serum cytokines content from the LBW group. Additionally, liver weight, TAG content in the hepatocytes and serum glucocorticoid levels were increased in the LBW group. The results demonstrate that IFR throughout pregnancy yields LBW offspring characterized by inhibited lipogenesis and lipolysis and reduced meWAT lipid storage at 12 weeks. The increased serum TAG content may contribute to the augmented synthesis and secretion of pro-inflammatory markers detected in the LBW group.

Acetate Upregulates GPR43 Expression and Function via PI3K-AKT-SP1 Signaling in Mammary Epithelial Cells during Milk Fat Synthesis.

This study investigated the mechanism underlying acetate-induced orphan G-protein-coupled receptor 43 (GPR43) expression and milk fat production. The mammary epithelial cells of dairy cows were treated with acetate, and the effects of GPR43 on acetate uptake and the expression of lipogenesis-related genes were determined by gas chromatography and quantitative polymerase chain reaction (qPCR), respectively. RNAi, inhibitor treatment, and luciferase assay were used to determine the effect of phosphoinositide 3-kinase-protein kinase B-specificity protein 1 (PI3K-AKT-SP1) signaling on acetate-induced GPR43 expression and function. The results showed that GPR43 was highly expressed in lactating cow mammary tissues, which was related to milk fat synthesis. 12 mM acetate significantly increased the GPR43 expression in mammary epithelial cells of dairy cows. In acetate-treated cells, GPR43 overexpression significantly increased the cellular uptake of acetate, the intracellular triacylglycerol (TAG) content, and acetate-induced lipogenesis gene expression. Acetate activated PI3K-AKT signaling and promoted SP1 translocation from the cytosol into the nucleus, where SP1 bound to the GPR43 promoter and upregulated GPR43 transcription. Moreover, the activation of PI3K-AKT-SP1 by acetate facilitated the trafficking of GPR43 from the cytosol to the plasma membrane. In conclusion, acetate upregulated GPR43 expression and function via PI3K-AKT-SP1 signaling in mammary epithelial cells, thereby increasing milk fat synthesis. These results provide an experimental strategy for improving milk lipid synthesis, which is important to the dairy industry.

Different Dietary Sources of Selenium Alleviate Hepatic Lipid Metabolism Disorder of Heat-Stressed Broilers by Relieving Endoplasmic Reticulum Stress.

As global warming continues, the phenomenon of heat stress (HS) in broilers occurs frequently. The alleviating effect of different selenium (Se) sources on HS-induced hepatic lipid metabolism disorders in broilers remains unclear. This study compared the protective effects of four Se sources (sodium selenite; selenium yeast; selenomethionine; nano-Se) on HS-induced hepatic lipid metabolism disorder and the corresponding response of selenotranscriptome in the liver of broilers. The results showed that HS-induced liver injury and hepatic lipid metabolism disorder, which were reflected in the increased activity of serum alanine aminotransferase (ALT), the increased concentration of triacylglycerol (TG) and total cholesterol (TC), the increased activity of acetyl-CoA carboxylase (ACC), diacylglycerol O-acyltransferase (DGAT) and fatty acid synthase (FAS), and the decreased activity of hepatic lipase (HL) in the liver. The hepatic lipid metabolism disorder was accompanied by the increased mRNA expression of lipid synthesis related-genes, the decreased expression of lipidolysis-related genes, and the increased expression of endoplasmic reticulum (ER) stress biomarkers (PERK, IRE1, ATF6, GRP78). The dietary supplementation of four Se sources exhibited similar protective effects. Four Se sources increased liver Se concentration and promoted the expression of selenotranscriptome and several key selenoproteins, enhanced liver antioxidant capacity and alleviated HS-induced ER stress, and thus resisted the hepatic lipid metabolism disorders of broilers exposed to HS. In conclusion, dietary supplementation of four Se sources (0.3 mg/kg) exhibited similar protective effects on HS-induced hepatic lipid metabolism disorders of broilers, and the protective effect is connected to the relieving of ER stress.

Lipid dynamics of 'Fenjiao' bananas (Musa ABB Pisang Awak) during post-ripening based on lipidomics analysis

Changes in cellular lipid homeostasis during ripening of ‘Fenjiao’ bananas (Musa ABB Pisang Awak) significantly affected its storage tolerance, and an in-depth understanding of the changes in cellular lipids during fruit ripening could provide more information and basic data for post-harvest quality regulation of 'Fenjiao' bananas. In this study, a comprehensive metabolomics approach was employed to annotate and characterize a total of 184 lipids, which encompassed glycerides, glycero-phospholipids, sphingolipids, and sterols. In the pulp of 'Fenjiao' bananas at three different stages of ripening (color-transferring, yellow-ripening, and over-ripening), of which glycerides and glycerophospho-lipids were the most predominant lipid constituents in the pulp of ‘Fenjiao’ bananas, with the percentages of the species accounting for 60.33% and 30.43%, respectively. During the post-ripening process of ‘Fenjiao’ bananas, the percentage of glycerides in the pulp exhibited a decreasing trend followed by an increasing trend. In contrast, the trend of glycerophospholipids was opposite to that of glycerides, showing an increasing trend followed by a decreasing trend. The tria-cylglycerol (TAG) content will increase significantly during the senescence stage of the 'Fenjiao' bananas, whereas the levels of diglycerides (DAG), Phosphatidylinositol (PI), Pho-sphatidylcholine (PC), and Phosphatidylethanolamine (PE) will gradually decrease. Through analysis of the differential lipid metabolites, it was discovered that these lipids were primarily enriched in the glycerolipid metabolism, glycerophospholipid metabolism, biosynthesis of unsaturated fatty acids, saturated fatty acid biosynthesis, and phosphatidylinositol signaling pathway. This study is the first to describe and analyze the lipid dynamics during the post-ripening process of 'Fenjiao' bananas, providing valuable insights into its cellular lipid metabolism during this stage.

Effect of pomegranate seed oil on egg production, egg quality and yolk fatty acid deposition in laying hen.

Pomegranate seed oil (PSO) contains punicic acid as well as conjugated linolenic acid isomers, including α-eleostearic and catalpic acids, along with phytosterols, especially β-sitosterol, campesterol and stigmasterol, with lipotropic impact and egg fortifying effect in laying hens. The present experiment was designed to examine the effects of PSO on egg production, egg quality, blood lipids and yolk fatty acid deposition in laying hens. A total of 360 Hy-line laying hens (w-80), at 25 weeks of age, were randomly allotted to five dietary treatments in a completely randomized design during a 10-week period. Experimental treatments consisted of a basal diet or supplementation of 1, 2, 3 and 4gPSO/kg to basal diet. Performance indicators and fatty acid composition of egg yolk were evaluated during different experimental periods. Blood lipid attributes were evaluated at the end of the experiment. Dietary supplementation of 4gPSO/kg feed increased daily feed intake and egg production rate of laying hens (p<0.05). There was not any significant influence of experimental treatments on egg quality, whereas an increasing trend observed in egg yolk colour of hens received dietary graded levels of PSO. Dietary supplemental 4g/kgPSO increased the proportion of yolk poly-unsaturated fatty acid (PUFA) concentration (p<0.05). Furthermore, the PUFA to saturated fatty acid ratio increased after dietary supplementation of 1 or 4g/kgPSO (p<0.05). Serum concentration of cholesterol, triacylglycerol and low-density lipoprotein decreased in response to the supplementation of more than 3gPSO/kg in the feed (p<0.05). In conclusion, dietary supplementation with 4g/kgPSO improved production rate and decreased blood lipids in laying hens. Moreover, dietary supplemental PSO modified yolk fatty acid deposition without detrimental effects on the egg quality.

Dietary cultured supernatant mixture of Cetobacterium somerae and Lactococcus lactis improved liver and gut health, and gut microbiota homeostasis of zebrafish fed with high-fat diet

Postbiotics have the ability to improve host metabolic disorders and immunity. In order to explore whether the postbiotics SWFC (cultured supernatant mixture of Cetobacterium somerae and Lactococcus lactis) repaired the adverse effects caused by feeding of high-fat diet (HFD), zebrafish were selected as the experimental animal and fed for 6 weeks, with dietary HFD as the control group, and HFD containing 0.3 g/kg and 0.4 g/kg SWFC as the treatment groups. The results indicated that addition of SWFC in the diet at a level of 0.3 and 0.4 g/kg didn't affect the growth performance of zebrafish (P > 0.05). Supplementation of dietary SWFC0.3 relieved lipid metabolism disorders through significant increasing in the expression of pparα and cpt1, and decreasing the expression of cebpα, pparγ, acc1 and dgat-2 genes (P < 0.05). Moreover, the content of triacylglycerol was markedly lower in the liver of zebrafish grouped under SWFC0.3 (P < 0.05). Dietary SWFC0.3 also improved the antioxidant capacity via increasing the expression level of ho-1, sod and gstr genes, and significant inducing malondialdehyde content in the liver of zebrafish (P < 0.05). Besides, dietary SWFC0.3 also notably improved the expression level of lysozyme, c3a, defbl1 and defbl2 (P < 0.05). The expression level of pro-inflammatory factors (nf-κb, tnf-α, and il-1β) were significantly decreased and the expression level of anti-inflammatory factor (il-10) was markedly increased in the postbiotics 0.3 g/kg group (P < 0.05). Feeding with SWFC0.3 supplemented diet for 6 weeks improved the homeostasis of gut microbiota and increased the survival rate of zebrafish after challenged with Aeromonus veronii Hm091 (P < 0.01). It was worth noting that the positive effect of dietary SWFC at a level of 0.3 g/kg was considerably better than that of 0.4 g/kg. This may imply that the effectiveness and use of postbiotics is limited by dosage.

Вплив S-естерів тіосульфокислот на окремі біохімічні показники крові щурів

The effect of S-esters of thiosulfonic acids - S-ethyl-4-aminobenzenethiosulfonate (ETS), S-allyl-4-aminobenzenethiosulfonate (ATS) and S-allyl-4-acetylaminobenzenethiosulfonate (AATS) at doses of 50 and 100 mg/kg body weight in rats on some biochemical parameters of protein and lipid metabolism in rats was investigated. The study was conducted in two stages on white male laboratory rats of the Wistar line, weighing 190–210 g. During the first stage of the study, animals of all experimental groups were administered by 500 µL of oil solutions of thiosulfonate esters at 100 mg per kg of body weight for 21 days. In the second stage of the study, the dosage was reduced to 50 mg per kg of body. Throughout both stages of the study, rats were divided into a control group (I) and three experimental groups (II, III, IV), with 5 animals in each. Rats in group II received ETS with their food, while group III received ATS, and group IV received AATS, all in appropriate doses. The animals of the control group were similarly given 500 µL of oil once a day in their diet. After the decapitation of animals, the activities of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, concentrations of total protein, urea, cholesterol and triacylglycerols were determined in blood plasma. As a result of the study, it was found that the use of sulfonic acid esters in the studied doses did not have a hepatotoxic effect on rats, as indicated by the normal activity of liver-indicating enzymes (ALT, ALP and alkaline phosphatase) in the blood plasma. In addition, sulfonic acid esters promoted protein synthesizing function, as evidenced by an increase in total protein concentration in the blood plasma and a decrease in urea – the end product of their decomposition. The studied esters had a positive effect on lipid metabolism, which was confirmed by a decrease in the concentration of triacylglycerol and cholesterol in the blood plasma, which, in turn, may contribute to the inhibition of the formation of their complexes in the liver - low-density lipoproteins. Probable changes in the concentration of total protein under the action of ETS and ATS and triacylglycerols under the action of ATS and AATS showed better effects of sulfonic acid esters at a dose of 100 mg/kg compared to a dose 50 mg/kg.

The transcription factor CREB3–2 regulated neutral lipase gene expression in ovary of Nilaparvata lugens

The cyclic AMP-responsive element-binding protein 3 (CREB3) members have unique regulatory roles in cellular lipid metabolism as transcription factors. Two CREB3 proteins in Nilaparvata lugens were identified and analyzed. In ovary, when silencing NlCREB3–2, triacylglycerol (TAG) content dramatically increased but glycerol and free fatty acid (FFA) significantly decreased, which implicated that NlCREB3–2 was involved in the lipase-related TAG metabolism. In N. lugens, five neutral lipases with complete features for TAG hydrolytic activity and high expression in ovary were focused. Among them, the expression levels of three neutral lipase genes were significantly down-regulated by NlCREB3–2 RNAi. The direct regulation of NlCREB3–2 towards the three neutral lipase genes was evidenced by the dual-luciferase reporter assay. After jointly silencing three neutral lipase genes, TAG and glycerol contents displayed similar changes as NlCREB3–2 RNAi. The study proved that NlCREB3–2 participated in TAG metabolism in ovary via the direct activation towards the ovary-specific neutral lipase genes.

Marked difference in liver fat measured by histology vs. magnetic resonance-proton density fat fraction: A meta-analysis

Pathologists quantify liver steatosis as the fraction of lipid droplet-containing hepatocytes out of all hepatocytes, whereas the magnetic resonance-determined proton density fat fraction (PDFF) reflects the tissue triacylglycerol concentration. We investigated the linearity, agreement, and correspondence thresholds between histological steatosis and PDFF across the full clinical spectrum of liver fat content associated with non-alcoholic fatty liver disease. Using individual patient-level measurements, we conducted a systematic review and meta-analysis of studies comparing histological steatosis with PDFF determined by magnetic resonance spectroscopy or imaging in adults with suspected non-alcoholic fatty liver disease. Linearity was assessed by meta-analysis of correlation coefficients and by linear mixed modelling of pooled data, agreement by Bland-Altman analysis, and thresholds by receiver operating characteristic analysis. To explain observed differences between the methods, we used RNA-seq to determine the fraction of hepatocytes in human liver biopsies. Eligible studies numbered 9 (N= 597). The relationship between PDFF and histology was predominantly linear (r= 0.85 [95% CI, 0.80-0.89]), and their values approximately coincided at 5% steatosis. Above 5% and towards higher levels of steatosis, absolute values of the methods diverged markedly, with histology exceeding PDFF by up to 3.4-fold. On average, 100% histological steatosis corresponded to a PDFF of 33.0% (29.5-36.7%). Targeting at a specificity of 90%, optimal PDFF thresholds to predict histological steatosis grades were ≥5.75% for ≥S1, ≥15.50% for ≥S2, and ≥21.35% for S3. Hepatocytes comprised 58 ± 5% of liver cells, which may partly explain the lower values of PDFF vs. histology. Histological steatosis and PDFF have non-perfect linearity and fundamentally different scales of measurement. Liver fat values obtained using these methods may be rendered comparable by conversion equations or threshold values. Magnetic resonance-proton density fat fraction (PDFF) is increasingly being used to measure liver fat in place of the invasive liver biopsy. Understanding the relationship between PDFF and histological steatosis fraction is important for preventing misjudgement of clinical status or treatment effects in patient care. Our analysis revealed that histological steatosis fraction is often significantly higher than PDFF, and their association varies across the spectrum of fatty liver severity. These findings are particularly important for physicians and clinical researchers, who may use these data to interpret PDFF measurements in the context of histologically evaluated liver fat content.

Dose-dependent effects of rumen-protected choline on hepatic metabolism during induction of fatty liver in dry pregnant dairy cows.

Objectives were to determine the effects of supplementing increasing amounts of choline ion on hepatic composition and mRNA abundance in pregnant dry cows subjected to a fatty liver induction protocol. Holstein cows (35 primiparous and 41 multiparous) at mean (± standard deviation) of 211 ± 9.9 days of gestation were blocked by body condition (3.59 ± 0.33) and assigned to receive 0, 6.45, 12.90, 19.35, and 25.80 g/day of choline ion as rumen-protected choline (RPC) as a top-dress for 14 days. Cows were fed for ad libitum intake on days 1 to 5 and restricted to 30% of the required net energy for lactation from days 6 to 14 of the experiment. Hepatic tissue was sampled on days 5 and 14 and analyzed for concentrations of triacylglycerol and glycogen, and mRNA abundance was investigated. Orthogonal contrasts evaluated the effects of supplementing RPC (0 g/day vs. rest), and the linear, quadratic, and cubic effects of increasing intake of choline ion from 6.45 to 25.80 g/day. Results are depicted in sequence of treatments from 0 to 25.8. During feed restriction, RPC reduced the concentration of hepatic triacylglycerol by 28.5% and increased that of glycogen by 26.1%, and the effect of increasing RPC intake on triacylglycerol was linear (6.67 vs. 5.45 vs. 4.68 vs. 5.13 vs. 3.81 ± 0.92% wet-basis). Feeding RPC during feed restriction increased abundance of transcripts involved in choline metabolism (CHKA, PLD1), synthesis of apolipoprotein-B100 (APOB100), and antioxidant activity (GPX3), and decreased the abundance of transcripts involved in hepatic lipogenesis (DGAT2, SREBF1) and acute phase response (SAA3). Most effects were linear with amount of choline fed. Changes in hepatic mRNA abundance followed a pattern of reduced lipogenesis and enhanced lipids export, which help explain the reduced hepatic triacylglycerol content in cows fed RPC. Choline exerts lipotropic effects in dairy cows by altering transcript pathways linked to hepatic lipids metabolism.

Enzyme-assisted aqueous extraction of fish oil from Baltic herring (Clupea harengus membras) with special reference to emulsion-formation, extraction efficiency, and composition of crude oil.

Enzyme-assisted aqueous extraction (EAAE) is a green, and scalable method to produce oil and protein hydrolysates from fish. This study investigated the role of different parameters on emulsion formation, oil recovery, and the composition of crude oil during EAAE of Baltic herring (Clupea harengus membras). Fatty acid compositions, lipid classes, tocopherols, and oxidation status of the EAAE crude oils were studied. Compared to solvent-extracted oil, EAAE resulted in a lower content of phospholipids accompanied by a 57% decrease in docosahexaenoic acid. Changing fish to water ratio from 1:1 to 2:1 (w/w) with ethanol addition led to the greatest reduction (72%) of emulsion, which resulted in an increase in oil recovery by 11%. The addition of ethanol alone, or reduction of enzyme concentration from 0.4% to 0.1% also reduced emulsion-formation significantly. Overall, emulsion reduction resulted in higher content of triacylglycerols and n-3 polyunsaturated fatty acids in the crude oil extracted.

Longitudinal characterization of the metabolome of dairy cows transitioning from one lactation to the next: Investigations in blood serum

The objective of this study was to characterize changes in the serum metabolome and various indicators of oxidative balance in dairy cows starting 2 wk before dry-off and continuing until wk 16 of lactation. Twelve Holstein dairy cows (body weight 745 ± 71 kg, body condition score 3.43 ± 0.66; mean ± SD) were housed in a tiestall barn from 10 wk before to 16 wk after parturition. Cows were dried off 6 wk before the expected calving date (mean dry period length = 42 d). From 8 wk before calving to 16 wk after calving, blood samples were taken weekly to study redox metabolism by determining antioxidant capacity, measured as the ferric-reducing ability of plasma, reactive oxidative metabolites, oxidative stress index, oxidative damage of lipids, measured as thiobarbituric acid reactive substances, and glutathione peroxidase activity. According to these results, dairy cows had the lowest serum antioxidant capacity and greater levels of oxidative stress during the dry-off period and the early postpartum period. For metabolomics, a subset of serum samples including wk -7 (before dry-off), -5 (after dry-off), -1, 1, 5, 10, and 15 relative to calving were used. A targeted metabolomics approach was performed using liquid chromatography and flow injection with electrospray ionization triple quadrupole mass spectrometry using the MxP Quant 500 kit (Biocrates Life Sciences AG). A total of 240 metabolites in serum were used in the final data analysis. Principal component analysis revealed a clear separation by days of sampling, indicating a remarkable shift in metabolic phenotype between the dry period and late and early lactation. Changes in many non-lipid metabolites associated with one-carbon metabolism, the tricarboxylic acid cycle, the urea cycle, and AA catabolism were observed in the study, with changes in AA serum concentrations likely related to factors such as energy and nitrogen balance, digestive efficiency, and changing diets. The study confirmed an extensive remodeling of the serum lipidome in peripartum dairy cows, highlighting the importance of changes in acylcarnitine (acylCN), phosphatidylcholines (PC), and triacylglycerols (TG), as they play a crucial role in lipid metabolism. Results showed that short-chain acylCN increased after dry-off and decreased thereafter, whereas lipid-derived acylCN increased around parturition, suggesting that more fatty acids could enter mitochondria. Phospholipids and sphingolipids in serum showed changes during lactation. In particular, concentrations of sphingomyelins, PC, and lysoPC decreased around calving but increased in mid- and late lactation. In contrast, concentrations of TG remained consistently low after parturition. The serum concentrations of bile acids fluctuated during the dry period and lactation, with glycocholic acid, cholic acid, glycodeoxycholic acid, and taurocholic acid showing the greatest concentrations. These changes are likely due to the interplay of diet, liver function, and the ability of the gut microbiota to convert primary to secondary bile acids. Overall, these descriptive results may aid in hypothesis generation and in the design and interpretation of future metabolite-based studies in dairy cows. Furthermore, they contribute to our understanding of the physiological ranges in serum metabolites relative to the lactation cycle of the dairy cow.