Liver Triglyceride Research Articles

Machine learning reveals the contribution of lipoproteins to liver triglyceride content and inflammation.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is currently the most common chronic liver disease worldwide and is strongly associated with metabolic comorbidities, including dyslipidemia. Herein, we aim to estimate the prevalence of MASLD and metabolic dysfunction-associated steatohepatitis (MASH) in Europeans with isolated hypercholesterolemia and isolated hypertriglyceridemia in the UK Biobank and to estimate the independent contribution of lipoproteins to liver triglyceride content. We selected 218,732 Europeans from the UK Biobank without chronic viral hepatitis and other causes of liver disease, of whom 14,937 with liver magnetic resonance imaging (MRI) data available. Next, to examine the relationships between traits in predicting liver triglyceride content, we compared the predictive performance of several machine learning methods and selected the best performing algorithms based on the minimum cross-validated mean squared error (MSE). There was an approximately 3-fold and 4-fold enrichment of MASLD and MASH in individuals with isolated hypertriglyceridemia (p=1.23E-41 and p=1.29E-10, respectively), whereas individuals with isolated hypercholesterolemia had a marginal higher rate of MASLD and no difference in MASH rate compared to control group (p=0.019 and p=0.97, respectively). Among machine learning methods, feed-forward neural network had the best cross-validation MSE on the validation set. Circulating triglycerides, after body mass index (BMI), were the second strongest independent predictor of liver proton density fat fraction (PDFF) with the largest absolute mean Shapley additive explanation (SHAP) value. Isolated hypertriglyceridemia is the second strongest, after obesity, independent predictor of MASLD/MASH. Individuals with hypertriglyceridemia, but not with hypercholesterolemia, should be screened for liver disease.

M6A RNA Methylation and Implications for Hepatic Lipid Metabolism.

This review presents a summary of recent progress in research on the N6-methyladenosine (m6A) modification and regulatory roles in hepatic lipid metabolism. As the most abundant internal modification of eukaryotic RNA, the m6A modification is a dynamic and reversible process of the m6A enzyme system, which includes writers, erasers, and readers. m6A methylation depressed lipid synthesis and facilitated lipolysis in liver. The depletion of m6A methyltransferase Mettl14/Mettl3 raised fatty acid synthase (FAS), stearoyl-CoA desaturase-1 (SCD1), acetyl-CoA carboxylase (ACC), and elongase of very long chain fatty acids 6 (ELOVL6) in rodent liver, causing increases in liver weight, triglyceride (TG) production, and content in hepatocytes. FTO catalyzed m6A demethylation and the suppression m6A reader YTHDC2 promoted hepatocellular TG generation and hepatic steatosis in C57BL/6 mice through sterol regulatory element-binding protein 1c (SREBP-1c) signaling pathway, which upregulated the lipogenic genes FAS, SCD1, ACC, recombinant acetyl coenzyme a carboxylase alpha, and cell death-inducing DNA fragmentation factor-like effector C (CIDEC). Furthermore, FTO overexpression did not only enhance mitochondrial fusion to impair mitochondrial function and lipid oxidation but also promoted lipid peroxidation, accompanied by excessive TG in hepatocytes and rodent liver. Elevated m6A modification potently suppressed hepatic lipid accumulation, while the shrinkage of m6A modification arose hepatic lipid deposition. These findings have highlighted the beneficial role of m6A RNA methylation in hepatic lipid metabolism, potentially protecting liver from lipid metabolic disorders.

A novel small-molecule PCSK9 inhibitor E28362 ameliorates hyperlipidemia and atherosclerosis.

Proprotein convertase subtilisin/kexin type 9 (PCSK9) binds to the epidermal growth factor precursor homologous domain A (EGF-A) of low-density lipoprotein receptor (LDLR) in the liver and triggers the degradation of LDLR via the lysosomal pathway, consequently leading to an elevation in plasma LDL-C levels. Inhibiting PCSK9 prolongs the lifespan of LDLR and maintains cholesterol homeostasis in the body. Thus, PCSK9 is an innovative pharmacological target for treating hypercholesterolemia and atherosclerosis. In this study, we discovered that E28362 was a novel small-molecule PCSK9 inhibitor by conducting a virtual screening of a library containing 40,000 compounds. E28362 (5, 10, 20 μM) dose-dependently increased the protein levels of LDLR in both total protein and the membrane fractionin both HepG2 and AML12 cells, and enhanced the uptake of DiI-LDL in AML12 cells. MTT assay showed that E28362 up to 80 μM had no obvious toxicity in HepG2, AML12, and HEK293a cells. The effects of E28362 on hyperlipidemia and atherosclerosis were evaluated in three different animal models. In high-fat diet-fed golden hamsters, administration of E28362 (6.7, 20, 60 mg·kg-1·d-1, i.g.) for 4 weeks significantly reduced plasma total cholesterol (TC), triglyceride (TG), low-density lipoprotein-cholesterol (LDL-C) and PCSK9 levels, and reduced liver TC and TG contents. In Western diet-fed ApoE-/- mice (20, 60 mg·kg-1·d-1, i.g.) and human PCSK9 D374Y overexpression mice (60 mg·kg-1·d-1, i.g.), administration of E28362 for 12 weeks significantly decreased plasma LDL-C levels and the area of atherosclerotic lesions in en face aortas and aortic roots. Moreover, E28362 significantly increased the protein expression level of LDLR in the liver. We revealed that E28362 selectively bound to PCSK9 in HepG2 and AML12 cells, blocked the interaction between LDLR and PCSK9, and induced the degradation of PCSK9 through the ubiquitin-proteasome pathway, which finally resulted in increased LDLR protein levels. In conclusion, E28362 can block the interaction between PCSK9 and LDLR, induce the degradation of PCSK9, increase LDLR protein levels, and alleviate hyperlipidemia and atherosclerosis in three distinct animal models, suggesting that E28362 is a promising lead compound for the treatment of hyperlipidemia and atherosclerosis.

#1957 Microbial and metabolomic remodeling by Sichuan dark tea-based formula improves obesity-induced renal lipid metabolism disorder in mice

Abstract Background and Aims The theory of medicine-food homology is long-standing and has been widely applied in traditional Chinese medicine. The Sichuan dark tea-based medicated dietary formula (alternatively referred to as Qing, or clarity in Chinese) is previously used for its lipid-lowering properties in apoE mice. This study further investigated the renoprotective effects of Qing on diet-induced obesity (DIO) mice and explored the specific mechanisms involved. Method Male C57BL/6 mice were randomly assigned to three groups, a control group, a DIO group, and a Qing treatment group, or the Qing group, with 8 mice in each group. The mice in the control group were given normal maintenance feed and purified water, and the other two groups were fed a high-fat diet for 12 weeks to establish the DIO model. After that, high-fat diet continued in the DIO group, while the Qing group was given Qing at the same time for 12 weeks, during which period the weight of the mice was monitored and recorded every week. The mice were sacrificed after 12 weeks. Serum samples were collected and the levels of triglyceride (TG), total cholesterol (TC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and albumin were measured to evaluate liver function. In addition, renal lipids were extracted to determine the levels of TG and TC in the kidney and periodic acid-Schiff (PAS) and oil red O stainings were performed to evaluate kidney pathological injury. Western blot was performed to determine the phosphorylated AMPK (pAMPK)/AMPK ratio in the kidney tissue. RT-qPCR and Western blot were used to determine the expression of proteins related to fatty acid oxidation and key proteins related to lipid synthesis. 16SrRNA and metabolomics were applied to analyze the gut microbiota in the intestinal contents and its metabolites. Results Compared with those of the control group, the levels of liver mass (P=0.0003), serum ALT(P < 0.0001), AST (P=0.0001), TC (P=0.0191) and TG (P=0.0101) in the model group were significantly increased. Qing treatment can effectively reduce liver mass (P=0.0316), and improve AST (P=0.0012), ALT (P=0.0027), TC (P=0.0200), TG (P=0.0499) levels of mice compared to those of the DIO group. Qing treatment inhibited the expression of lipid synthesis related genes (SREBP-1, FASN and SCD1) and promoted the expression of fatty acid oxidation related genes (CPT1A, PGC1α and PPARγ) in kidneys (Fig. 1). Obesity-triggered dysfunction of structure and composition of gut microbiota were improved by Qing (Fig. 2), where the content of short-chain fatty acids, especially isovaleric acid and propionic acid, were also restored (Fig. 3). Conclusion Our data suggested that Sichuan dark tea-based medicated dietary formula may improve renal lipid metabolism by regulating gut microbiota and the levels of intestinal short-chain fatty acids, thereby protecting obesity-related kidney injury. Isovaleric acid and propionic acid may be the metabolites key to its regulation of gut microbiota.

The Influence of Emodin Succinyl Ethyl Ester on Non-alcoholic Steatohepatitis Induced by a Diet High in Fructose, Cholesterol, and Fat in Mice.

Nonalcoholic steatohepatitis (NASH) is a subtype of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis and evidence of hepatocyte injury (ballooning) and inflammation, with or without liver fibrosis. In this study, after 12 weeks of induction, the mice were treated with emodin succinyl ethyl ester (ESEE) for four weeks at doses of 10/30/90 mg/kg/d. The blood analysis of experimental endpoints showed that ESEE exhibited significant therapeutic effects on the progression of disorders of glycolipid metabolism and the induced liver injury in the model animals. Histopathological diagnosis of the liver and total triglyceride measurements revealed that ESEE had a significant therapeutic effect on the histopathological features of nonalcoholic fatty liver disease/hepatitis, such as cellular steatosis and activation of intrahepatic inflammation. Additionally, ESEE was able to improve hepatocyte fat deposition, steatosis, and the course of intrahepatic inflammatory activity. Furthermore, it showed some inhibitory effect on liver fibrosis in the model animals. In summary, this study confirms the therapeutic effects of ESEE on the NAFLD/NASH model in C57BL/6J mice induced by a high-fat, high cholesterol, and fructose diet. These effects were observed through improvements in liver function, inhibition of fibrosis, and inflammatory responses. Changes in blood glucose levels, blood lipid metabolism, liver histopathological staining, liver fibrosis staining, and related pathological scores further supported the therapeutic effects of ESEE. Therefore, this study has important implications for the exploration of novel drugs for nonalcoholic fatty liver disease.

Effects of low protein feed on hepato-intestinal health and muscle quality of grass carp (Ctenopharyngodon idellus)

In this study, grass carp (33.28 ± 0.05 g) were fed three diets for 8 weeks: control (crude protein [CP] 30%, crude lipid [CL] 6%), low protein (LP; CP16%, CL6%), and low protein with high-fat (LPHF; CP16%, CL10%). The final body weight decreased in the LP and LPHF groups compared to the Control (P < 0.05). Liver triglycerides, total cholesterol, and nonesterified fatty acids were higher in the LP group than the Control, whereas these indexes in the LPHF group were higher than those in the LP group (P < 0.05). The LP group had intestinal barrier damage, while the LPHF group had a slight recovery. TNF-α, IL-8, and IL-1β content were lower in the LP group than in the Control (P < 0.05), and even higher in the LPHF group (P < 0.05). The expressions of endoplasmic reticulum stress-related genes Activating transcription factor 6 (ATF-6) and Glucose-regulated protein (GRP78) were higher in the LPHF group against the LP group (P < 0.05). The IL-1β and TNF-α content negatively correlated with intestinal Actinomycetes and Mycobacterium abundance (P < 0.05). The muscle fiber diameter was smaller in both the LP and LPHF groups than the control (P < 0.05), with the LP group showing metabolites related to protein digestion and absorption, and LPHF group exhibiting metabolites related to taste transmission. The results demonstrate reducing dietary protein affects growth, causing liver lipid accumulation, reduced enteritis response, and increased muscle tightness, while increasing fat content accelerates fat accumulation and inflammation.

On the issue of the effectiveness and bioequivalence of isotretinoin Lidose

BACKGROUND: Acne is one of the most common dermatoses. The most effective drug for the treatment of severe forms of acne is systemic isotretinoin, which affects all links in the pathogenesis of acne. The article presents scientific data on the innovative drug Aknecutan, which uses the patented Lidose technology in its production. The use of isotretinoin in the composition of innovative product with Lidose technology makes it possible to reduce the amount of isotretinoin taken by the patient by 20% without compromising the therapeutic effectiveness of the drug. AIM: to analyze comparative studies of bioavailability and relevant pharmacokinetic parameters, which made it possible to prove that the initial dosages of 8 and 16 mg with Lidose technology are bioequivalent to dosages of 10 and 20 mg of the usual form of isotretinoin. MATERIALS AND METHODS: Over the past 7 years, 1044 patients have received acne treatment for moderate to severe acne (651; 62.4% women and 393; 37.6% men) in a daily dose of 0.4–0.8 mg per 1 kg of body weight with a total dose of the drug ― 100–120 mg/kg per course of therapy. RESULTS: After therapy, clinical remission was achieved in all patients, which required from 7 to 12 months of treatment, depending on the daily dose of the drug. Among the side effects in all patients, cheilitis and retinoic dermatitis of the face were noted, which were completely resolved when using moisturizers and sticks. An increase in liver enzymes, triglycerides and lipoproteins was noted in 5–10% and did not exceed 20–30% of the norm and did not require discontinuation of therapy. At the end of treatment, these indicators returned to normal. Other side effects were extremely rare. Relapses of the disease are most often caused by a low total dose of the drug or the presence of endocrinological and gynecological diseases. CONCLUSION: Thus, innovative product with Lidose technology is one of the most highly effective and safe systemic retinoids for the treatment of moderate to severe acne. Comparative studies of bioavailability and corresponding pharmacokinetic parameters have demonstrated the bioequivalence of isotretinoin in the composition of innovative product with Lidose technology, which fully corresponds to that in the original preparation.

Dietary lipid sources affect growth performance, lipid deposition, antioxidant capacity and inflammatory response of largemouth bass (Micropterus salmoides)

The present study explored the effects of different lipid sources on growth performance, lipid deposition, antioxidant capacity, inflammatory response and disease resistance of largemouth bass (Micropterus salmoides). Four isonitrogenous (crude protein 50.46 %) and isolipidic (crude lipid 11.12 %) diets were formulated to contain 7 % of different oil sources including fish oil (FO) (control), soybean oil (SO), linseed oil (LO) and coconut oil (CO). Largemouth bass with initial body weight of 36.0 ± 0.2 g were randomly distributed into 12 tanks, with 30 fish per tank and 3 tanks per treatment. The fish were fed with the experiment diets twice daily for 8 weeks. The results indicated that the weight gain of largemouth bass fed the FO diet was significantly higher than that of fish fed the LO and CO diets. The liver crude lipid content in FO group was significantly higher than other groups, while the highest liver triglyceride content was showed in SO group and the lowest was detected in LO group. At transcriptional level, expression of lipogenesis related genes (pparγ, srebp1, fas, acc, dgat1 and dgat2) in the SO and CO group were significantly higher than the FO group. However, the expression of lipolysis and fatty acids oxidation related genes (pparα, cpt1, and aco) in vegetable oils groups were significantly higher than the FO group. As to the antioxidant capacity, vegetable oils significantly reduced the malondialdehyde content of largemouth bass. Total antioxidant capacity in the SO and LO groups were significantly increased compared with the FO group. Catalase in the LO group was significantly increased compared with the FO group. Furthermore, the ER stress related genes, such as grp78, atf6α, atf6β, chop and xbp1 were significantly enhanced in the vegetable oil groups compared with the FO group. The activity of serum lysozyme in vegetable oil groups were significantly higher than in FO group. Additionally, the relative expression of non-specific immune related genes, including tlr2, mapk11, mapk13, mapk14, rela, tgf-β1, tnfα, 5lox, il-1β and il10, were all significantly increased in SO and CO groups compared to the other groups. In conclusion, based on the indexes including growth performance, lipid deposition, antioxidant capacity and inflammatory response, SO and LO could be alternative oil sources for largemouth bass.

Puerarin Modulates Hepatic Farnesoid X Receptor and Gut Microbiota in High-Fat Diet-Induced Obese Mice.

Obesity is associated with alterations in lipid metabolism and gut microbiota dysbiosis. This study investigated the effects of puerarin, a bioactive isoflavone, on lipid metabolism disorders and gut microbiota in high-fat diet (HFD)-induced obese mice. Supplementation with puerarin reduced plasma alanine aminotransferase, liver triglyceride, liver free fatty acid (FFA), and improved gut microbiota dysbiosis in obese mice. Puerarin's beneficial metabolic effects were attenuated when farnesoid X receptor (FXR) was antagonized, suggesting FXR-mediated mechanisms. In hepatocytes, puerarin ameliorated high FFA-induced sterol regulatory element-binding protein (SREBP) 1 signaling, inflammation, and mitochondrial dysfunction in an FXR-dependent manner. In obese mice, puerarin reduced liver damage, regulated hepatic lipogenesis, decreased inflammation, improved mitochondrial function, and modulated mitophagy and ubiquitin-proteasome pathways, but was less effective in FXR knockout mice. Puerarin upregulated hepatic expression of FXR, bile salt export pump (BSEP), and downregulated cytochrome P450 7A1 (CYP7A1) and sodium taurocholate transporter (NTCP), indicating modulation of bile acid synthesis and transport. Puerarin also restored gut microbial diversity, the Firmicutes/Bacteroidetes ratio, and the abundance of Clostridium celatum and Akkermansia muciniphila. This study demonstrates that puerarin effectively ameliorates metabolic disturbances and gut microbiota dysbiosis in obese mice, predominantly through FXR-dependent pathways. These findings underscore puerarin's potential as a therapeutic agent for managing obesity and enhancing gut health, highlighting its dual role in improving metabolic functions and modulating microbial communities.

Fish oil supplementation during pregnancy decreases liver endocannabinoid system and lipogenic markers in newborn rats exposed to maternal high-fat diet.

Maternal high-fat diet (HF) programs obesity, metabolic dysfunction-associated steatotic liver disease (MASLD), hypertriglyceridemia, and hyperglycemia associated with increased endocannabinoid system (ECS) in the liver of adult male rat offspring. We hypothesized that maternal HF would induce sex specific ECS changes in the liver of newborn rats, prior to obesity onset, and maternal fish oil (FO) supplementation would reprogram the ECS and lipid metabolism markers preventing liver triglycerides (TG) accumulation. Female rats received a control (CT) (10.9% fat) or HF (28.7% fat) diet 8weeks prior to mating and during pregnancy. A subgroup of HF dams received 3% FO supplementation in the HF diet (35.4% fat) during pregnancy (HFFO). Serum hormones and liver TG, ECS, lipid metabolism, oxidative stress and autophagy markers were assessed in male and female newborn offspring. Maternal HF diet increased liver cannabinoid receptor 1 (CB1) in males and decreased CB2 in females, with no effect on liver TG. Maternal FO supplementation reduced liver CB1 regardless of the offspring sex, but reduced TG liver content only in females. FO reduced the liver content of the endocannabinoid anandamide in males, and the content of 2-arachidonoylglycerol in both sexes. Maternal HF increased lipogenic and decreased lipid oxidation markers, and FO induced the opposite regulation in the liver of offspring. Prenatal HF and FO differentially modulate liver ECS in the offspring before obesity and MASLD development. These results suggest that maternal nutrition at critical stages of development can modulate the offspring's ECS, predisposing or preventing the onset of metabolic diseases.

Evaluation of propolis hepatotoxicity in male rats

Background: Propolis is a natural resinous combination that honeybees produce from the materials they gather from plant parts, buds, and exudates. Numerous favorable pharmacological qualities have been demonstrated for propolis. Objectives: This study aimed to investigate the hepatotoxic effects of ethanolic propolis extract on the liver of male rats. Methods: In this research, 40 male rats were divided randomly into five groups: 1. Control 2. Sham (solvent), and 3. Three experimental groups (ethanolic propolis extract at doses of 50,100 and 200 mg/kg). All materials were administered by oral gavage once daily for 13 consecutive days. On the 14th day, blood sampling was performed to measure serum levels of liver function enzymes and triglycerides. After deep induction of anesthesia, the liver of the rats was removed for histopathological studies. Data were analyzed using ANOVA and Tukey’s test (p &lt;0.05). Results: The data showed that the administration of propolis significantly increased the serum levels of aminotransferases in a dose-dependent manner and decreased triglycerides, accompanied by pathological changes. Conclusions: The results of this study indicate that the administration of propolis is associated with liver toxicity, and it seems that it should be consumed more carefully. Keywords: Alanine aminotransferase, Aspartate aminotransferase, Propolis, Hepatotoxicity Triglycerides

Metabolic Effects of Short-Term High-Fat Intake Vary Depending on Dietary Amino Acid Composition

BackgroundIt is generally accepted that excessive fat intake has undesirable effects on the energy metabolism of our body. Dietary amino acid composition is also critical to the regulation of lipid metabolism. ObjectivesThis study aimed to investigate whether high-fat diets (HFDs) with different amino acid deficiencies lead to different metabolic outcomes. MethodsSix-wk-old male Wistar rats were fed either a control diet (CN; 3.7 kcal/g, 12% calories from fat) or HFDs (5.1 kcal/g, 60% calories from fat) with 7 different amino acid compositions [control or methionine, arginine, histidine, lysine, threonine, or branched-chain amino acids (BCAAs) deficient], for 7 d. Tissue weights and lipid accumulation in the liver, skeletal muscle, and adipose tissue were measured, and serum biochemical parameters were analyzed. ResultsAlthough the food intake of the HFD groups was a little less than that of the CN group, the total calorie intakes were comparable among the groups, except for histidine-deficient and BCAA-deficient groups. In rats fed am HFD with a control amino acid composition (HFCN), dramatic increase in triglyceride (TG) accumulation in the liver and serum LDL cholesterol concentration were observed compared with the CN group. However, when the arginine content in the diet was reduced, liver TG accumulation was completely inhibited, with no apparent effects on serum lipoprotein-cholesterol concentrations. Meanwhile, deficiency of the other amino acids, such as threonine, reversed HFD-induced upregulation of serum LDL cholesterol. ConclusionsIt is observed that although the rats ingested an excessive amount of fat, neither ectopic fat accumulation nor dyslipidemia were always induced at least in the short term; hence, the consequent metabolic change was dependent on the dietary amino acid composition. These findings introduce an important perspective regarding HFD regimens in both scientific and clinical contexts.

Quantitative ultrasound techniques and biochemical markers to assess liver steatosis and fibrosis in newly diagnosed acromegaly

PurposeThe liver is known to be protected from steatosis under the influence of high GH/IGF-1. Cytokeratin 18 (CK18) and insulin-like growth factor binding protein 7 (IGFBP7) increase in liver steatosis and fibrosis. The aim of this study was to use quantitative ultrasound techniques and biochemical markers to assess liver steatosis and liver fibrosis in newly diagnosed acromegaly.MethodsThis single-center, cross-sectional study included 23 patients with newly diagnosed acromegaly and 46 age, sex, body mass index (BMI) and waist circumference (WC)-matched controls. Liver steatosis was assessed using tissue attenuation imaging (TAI), and stiffness, indicative of fibrosis, was assessed by shear wave elastography (SWE). Serum IGFBP7 and CK18 were studied by ELISA.ResultsThe acromegaly group had significantly lower liver steatosis (p = 0.006) and higher liver stiffness (p = 0.004), serum IGFBP7 (p = 0.048) and CK18 (p = 0.005) levels than the control group. The presence of fibrosis (p = 0.012) was significantly higher in the acromegaly group than in the control group. Moreover, CK18 was positively correlated with liver stiffness, WC, HOMA-IR, HbA1c, and triglyceride. In the acromegaly group, liver steatosis was negatively correlated with GH level. Stepwise multiple linear regression analysis revealed that BMI (p = 0.008) and CK18 (p = 0.015) were independent risk factors for increased liver stiffness.ConclusionThis study showed that there was an increased presence of liver fibrosis independent of liver steatosis in newly diagnosed acromegaly. Serum CK18 appears to be a potential marker of increased liver fibrosis in acromegaly.

Exploring the dynamic three-dimensional chromatin architecture and transcriptional landscape in goose liver tissues underlying metabolic adaptations induced by a high-fat diet

BackgroundGoose, descendants of migratory ancestors, have undergone extensive selective breeding, resulting in their remarkable ability to accumulate fat in the liver and exhibit a high tolerance for significant energy intake. As a result, goose offers an excellent model for studying obesity, metabolic disorders, and liver diseases in mammals. Although the impact of the three-dimensional arrangement of chromatin within the cell nucleus on gene expression and transcriptional regulation is widely acknowledged, the precise functions of chromatin architecture reorganization during fat deposition in goose liver tissues still need to be fully comprehended.ResultsIn this study, geese exhibited more pronounced changes in the liver index and triglyceride (TG) content following the consumption of the high-fat diet (HFD) than mice without significant signs of inflammation. Additionally, we performed comprehensive analyses on 10 goose liver tissues (5 HFD, 5 normal), including generating high-resolution maps of chromatin architecture, conducting whole-genome gene expression profiling, and identifying H3K27ac peaks in the livers of geese and mice subjected to the HFD. Our results unveiled a multiscale restructuring of chromatin architecture, encompassing Compartment A/B, topologically associated domains, and interactions between promoters and enhancers. The dynamism of the three-dimensional genome architecture, prompted by the HFD, assumed a pivotal role in the transcriptional regulation of crucial genes. Furthermore, we identified genes that regulate chromatin conformation changes, contributing to the metabolic adaptation process of lipid deposition and hepatic fat changes in geese in response to excessive energy intake. Moreover, we conducted a cross-species analysis comparing geese and mice exposed to the HFD, revealing unique characteristics specific to the goose liver compared to a mouse. These chromatin conformation changes help elucidate the observed characteristics of fat deposition and hepatic fat regulation in geese under conditions of excessive energy intake.ConclusionsWe examined the dynamic modifications in three-dimensional chromatin architecture and gene expression induced by an HFD in goose liver tissues. We conducted a cross-species analysis comparing that of mice. Our results contribute significant insights into the chromatin architecture of goose liver tissues, offering a novel perspective for investigating mammal liver diseases.

Paneth cell-specific TCF4 down-regulation potentiates alcohol-induced dysbiosis of gut microbiota and tissue injury at the gut-liver axis

Introduction: Alcohol misuse results in hepatitis, pancreatitis, and neurodegenerative disorders. Alcohol consumption alters gut microbiota and increases gut permeability, leading to endotoxemia and multiple organ damage. However, the cellular and molecular mechanisms of alcohol-induced microbiota dysbiosis and barrier dysfunction remain poorly defined. Antimicrobial peptides such as α-defensins, secreted by the Paneth cells, regulate gut microbiota homeostasis. We previously reported that ethanol (EtOH) feeding reduces α-defensin expression in mice. α-Defensin expression is regulated by Wnt signaling and T-cell factor 4 (TCF4). We investigated the role of Paneth cell TCF4 in alcohol-induced microbiota dysbiosis and tissue injury at the gut-liver axis. Materials and methods: TCF4fl/wt (WT) and TCF4fl/wt-Defa6Cre (KD; heterozygous Paneth cell-specific knockout of TCF4) mice were fed a Lieber-DiCarli liquid diet with or without EtOH (0% 2d, 1% 2d, 2% 2d, 4% 1wk, 5% 1wk, &amp; 6% 1wk) (EF). Control groups were pair-fed (PF) isocaloric EtOH-free diet. Intestinal permeability was measured by the vascular-to-luminal flux of FITC-inulin (6 kDa) in vivo, and tight junction (TJ) and adherens junction (AJ) integrity were assessed by confocal microscopy for occludin, ZO-1, E-cadherin, and β-catenin. Paneth cell function and mucosal inflammation were assessed by RT-PCR for defensins and cytokines. Gut microbiota was analyzed by 16S rRNA sequencing of colonic flushing. Plasma lipopolysaccharide (LPS) and cytokines were measured to evaluate endotoxemia and systemic inflammation. Liver damage was assessed by measuring plasma AST, liver triglyceride, and cytokine mRNA. Results and conclusion: EtOH reduced TCF4 expression in the ileum in both WT and KD mice; lowest TCF4 expression was observed in KD-EF mice. Similarly, the expression of DEFA5 and DEFA6 was reduced by EtOH in WT and KD mice, with the lowest expression in KD-EF mice. EtOH-induced mucosal permeability was associated with reduced staining for TJ and AJ proteins, indicating the mucosal barrier dysfunction. EtOH increased intestinal mRNA for IL-1β, IL-6, TNFα, and MCP-1, indicating the mucosal inflammatory response. EtOH-induced gut permeability, TJ/AJ disruption, and mucosal inflammation were significantly higher in KD-EF mice than in WT-EF mice. Shannon index analysis indicated that EtOH reduced α-diversity of microbiota in KD but not in WT mice. Firmicutes: Bacteriodetes ratio and the abundance of Verrucomicrobia were reduced by EtOH in WT but not in KD mice. The abundance of Bacillus was increased by EtOH both in WT and KD mice; however, this effect was more severe in KD mice. EtOH-induced plasma LPS and cytokine elevations were higher in KD mice than in WT mice. Elevation of plasma AST, liver triglyceride, and liver cytokine mRNA indicated EtOH-induced liver damage; the damage was more severe in KD mice. These data indicate that Paneth cell TCF4 downregulation exacerbates alcohol-induced microbiota dysbiosis, gut barrier dysfunction, endotoxemia, systemic inflammation, and liver damage; suggesting that Paneth cell Wnt signal downregulation plays a crucial role in alcohol-associated organ damage. NIH/NIAA - R01AA012307, AA029270; Veterans Administration - IO1BX003014. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Liver-specific mitochondrial amidoxime-reducing component 1 (Mtarc1) knockdown protects the liver from diet-induced MASH in multiple mouse models.

Human genetic studies have identified several mitochondrial amidoxime-reducing component 1 (MTARC1) variants as protective against metabolic dysfunction-associated steatotic liver disease. The MTARC1 variants are associated with decreased plasma lipids and liver enzymes and reduced liver-related mortality. However, the role of mARC1 in fatty liver disease is still unclear. Given that mARC1 is mainly expressed in hepatocytes, we developed an N-acetylgalactosamine-conjugated mouse Mtarc1 siRNA, applying it in multiple in vivo models to investigate the role of mARC1 using multiomic techniques. In ob/ob mice, knockdown of Mtarc1 in mouse hepatocytes resulted in decreased serum liver enzymes, LDL-cholesterol, and liver triglycerides. Reduction of mARC1 also reduced liver weight, improved lipid profiles, and attenuated liver pathological changes in 2 diet-induced metabolic dysfunction-associated steatohepatitis mouse models. A comprehensive analysis of mARC1-deficient liver from a metabolic dysfunction-associated steatohepatitis mouse model by metabolomics, proteomics, and lipidomics showed that Mtarc1 knockdown partially restored metabolites and lipids altered by diet. Taken together, reducing mARC1 expression in hepatocytes protects against metabolic dysfunction-associated steatohepatitis in multiple murine models, suggesting a potential therapeutic approach for this chronic liver disease.

Exploring the relationship between dietary rapeseed meal, condensed tannin and growth, nutrive metabolism in largemouth bass (Micropterus salmoides)

This study evaluated the effects of rapeseed meal (RM) and condensed tannin (CT) on the growth and nutritional metabolism of largemouth bass (Micropterus salmoides), and speculated whether there was interaction between anti-nutritional factors in RM. Eight diets were formulated for 55-day feeding trial, six of which were practical diet groups, including control group (CG), five RM inclusive groups with graded RM levels of 5% (RM5), 10% (RM10), 15% (RM15), 20% (RM20) and 25% (RM25) partially replacing fishmeal, and the other two were semi-purified diets with 0.062% CT (CT5) ≈ the CT content in the RM5 and 0.31% CT (CT25) ≈ the CT content in the RM25. The results of the experiments on replacing fishmeal with RM demonstrated that with the increase of RM substitution level, the weight gain rate (WGR), survival rate (SR) and specific growth rate (SGR) of largemouth bass showed a downward trend. High levels of RM led to the inhibition of digestive enzyme activity in largemouth bass, as well as the manifestation of abnormal markers related to protein, fat, and carbohydrate metabolism in both plasma and liver. RM reduced muscle protein and fat content, although the effect was not statistically significant at 5% RM level. The results of CT concentration experiments showed that the addition of 0.31% CT significantly reduced WGR, SGR, SR, protein efficiency ratio (PER) and gastrointestinal digestive enzyme activity, and significantly increased the feed coefficient ratio (FCR), plasma ammonia (PA), plasma glucose (PG), and hepatic glycogen (HG) and liver triglyceride (TG). The addition of 0.062% CT significantly reduced PG and HG. Supplementation of CT significantly reduced muscle fat. Among the groups of CT supplementation and RM, CT5 exhibited superior WGR, PER and FCR compared to RM5, along with enhanced intestinal trypsin, amylase activity, liver glutamic pyruvic transaminase (GPT) activity and decreased content of HG and liver TG; CT25 exhibited decreased activities of gastric lipase (LPS), enteric trypsin and pepsin, and increased content of total cholesterol (T-CHO) and glucose in plasma in compariosn to RM25, accompanied with no significant change in growth performance. Therefore, largemouth bass exhibited tolerance to a 5% inclusion of RM in the feed without compromising their growth, digestion and metabolic functions. The incorporation of 5% RM, equivalent to a supplemental 0.062% CT, had regulatory effects on the digestion and metabolism of largemouth bass while improving feed utilization. There was an interaction among anti-nutritional factors in RM, with synergistic effect being evident at low RM levels, whereas antagonism more promient at high levels of RM.

C-Jun N-Terminal Kinase-2 (JNK2) Plays a Crucial Role in Alcohol and Corticosterone-Induced Dysbiosis of Gut Microbiota and Tissue Injury at the Gut-Liver Axis

Introduction: About 15% of heavy drinkers develop liver disease, suggesting the “Multiple hit hypothesis” of Alcohol-Associated Liver Diseases (AALD). Chronic stress is a potential second hit in AALD pathogenesis. Our recent study showed that alcohol-induced gut and liver injury is exacerbated by chronic restraint stress or corticosterone. JNK2 plays an essential role in stress-induced cell injury. In this study, we investigated the role of JNK2 in ethanol (EtOH) and corticosterone-induced gut and liver injury and microbiota dysbiosis in mice. Methods: Wildtype (WT) and JNK2 knockout (JNK2-KO) mice (male and female; 8-10 wks) were fed a Lieber-DiCarli liquid diet with or without EtOH (0% 2d, 1% 2d, 2% 2d, 4% 1wk, 5% 1wk, &amp; 6% 1wk). Control groups were pair-fed isocaloric EtOH-free diet. One group of pair-fed and EtOH-fed WT and JNK2-KO mice were administered corticosterone (CORT, 25 mg/kg/day; s.c.). Intestinal permeability was measured by vascular-to-luminal flux of FITC-inulin in vivo, tight junction (TJ) and adherens junction (AJ) integrity was assessed by confocal microscopy for occludin, ZO-1, E-cadherin, and β-catenin, and mucosal inflammation by RT-PCR for cytokines/chemokines. Plasma lipopolysaccharide (LPS) and cytokines were measured to evaluate endotoxemia and systemic inflammation. Liver damage was assessed by measuring plasma AST/ALT, liver triglyceride, and cytokine/chemokine mRNA. Gut microbiota was analyzed by 16S rRNA sequencing of colonic flushing followed by bioinformatics analyses. Results and conclusion: In WT mice, EtOH feeding increased intestinal permeability, disrupted epithelial TJ and AJ, and elevated mucosal cytokine expression, indicating epithelial barrier dysfunction and mucosal inflammation. EtOH increased plasma LPS and cytokine/chemokine levels, indicating endotoxemia and systemic inflammation. Plasma AST/ALT and liver triglyceride levels were increased, indicating EtOH-induced liver damage. CORT significantly elevated EtOH-induced intestinal permeability, TJ/AJ disruption, endotoxemia, systemic inflammation, and liver damage in WT mice. These effects of EtOH and CORT were absent in JNK2-KO mice. Microbiota α-diversity was higher in JNK2-KO mice than in WT mice, and β-diversity analysis showed that the microbiota composition in WT mice differed from that of KO mice. Microbiota α- and β-diversities were altered by EtOH and CORT in WT mice but not in JNK2-KO mice. The relative abundance of Nocardiaceae and Verrucomicrobiaceae was high, and Ruminococcaceae and Bacillaceae were low in KO mice. CORT decreased the abundance of Caulobacteriaceae and Ruminococcaceae and increased Verrucomicrobiaceae and Lactobacillaceae in WT but not KO mice. EtOH increased Ruminococcaceae and Bacillaceae and decreased Lactobacillaceae in WT mice but not KO mice. CORT-induced modulation of EtOH-induced microbiota dysbiosis was observed in WT mice but not KO mice. In conclusion, these data demonstrate that JNK2 regulates gut microbiota in mice, and JNK2 deficiency confers resistance to alcohol and corticosterone-induced tissue injury and microbiota dysbiosis. Acknowledgements: NIH/NIAAA - R01AA012307, AA029270; VA - IO1BX003014. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

High Fat Diet Induced Lipid Deposition and Perilipin 2 Expression in Mouse Liver Is Attenuated by Endothelin-1 Receptor A Blockade

Obesity is associated with dyslipidemia and lipid deposition into liver tissue. Circulating endothelin-1 (ET-1) is elevated in patients with obesity, and our lab has demonstrated that ET-1 is increased in liver of mice fed high fat (HFD). Interestingly, treatment with atrasentan attenuates reduces circulating triglycerides and free fatty acids and reduces lipid deposition into liver of mice fed HFD for 10 weeks; however, the mechanisms are not known. Perilipin 2 (Plin2) is a protein expressed in adipocytes and hepatocytes that is integral to lipid droplet formation by forming a coating around the droplet. We hypothesized that ET-1 receptor blockade reduces liver lipid deposition in obese mice by reducing Plin2 expression. To test this hypothesis, mice were fed normal (NMD) or HFD for 10 weeks and treated with the ET-1 receptor A (ETA) antagonist atrasentan for weeks 9-10. ET-1 receptor expression was significantly increased in HFD fed mice compared to NMD. As previously demonstrated, HFD fed mice had significantly higher liver triglyceride content compared to NMD controls, and this was attenuated in mice treated with atrasentan (ATR). As expected, Plin2 expression in liver tissue was significantly elevated in HFD mice compared to NMD (91.7±17.4 vs. 60.8±14.4 copies/pg RNA), an affect that was abolished in mice treated with atrasentan (NMD, 60.8±14.4; HFD, 91.7±17.4; NMD + ATR, 70.2±10.8; HFD + ATR, 26.3±5.8 copies/10pg RNA). These data suggest that ET-1 promotes lipid accumulation in liver of obese mice by reducing Plin2 expression. Funding: R01 DK124437, P30GM149404, and T32HL105324. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Hepatokine ITIH3 Protects Against Hepatic Steatosis by Downregulating Mitochondrial Bioenergetics and De Novo Lipogenesis

Accumulating evidence suggest that mitochondrial functions are altered and contribute to the pathogenesis of non-alcoholic fatty liver disease (NAFLD). As a result, research is being conducted to discover targets that alter mitochondrial functions to ameliorate NAFLD, and its progression towards non-alcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). Recent studies demonstrate that liver secretory proteins regulate normal development, obesity, simple steatosis to NASH progression. Inter-α-trypsin inhibitors (ITI) are one such proteins secreted by liver, altered in NAFLD, but their functional importance in mitochondrial metabolism is poorly understood. Here, we have identified that ITIH3 is a potential candidate gene that protects against NAFLD by targeting mitochondrial metabolism. We used an integrative multiomics approach using transcriptomic data from approximately 100 different mouse strains called hybrid mouse diversity panel (HMDP) and a cohort of bariatric surgery patients and identified Itih3/ITIH3 expression to be inversely associated with NAFLD/NASH progression and hepatic TG accumulation. Our network enrichment analyses revealed NAFLD-related pathways such as mitochondria, TCA cycle, fatty acid metabolism, cholesterol metabolism, coagulation and fibrinolysis. Next, disease enrichments by ToppGene revealed metabolic syndrome-related disease traits including dyslipidemia, steatosis, NASH and fibrosis. Our in vitro and in vivo studies using loss and gain of function mouse and cell culture models demonstrated that hepatic ITIH3 reduced liver triglyceride accumulation and de novo lipogenesis (DNL). Remarkably, hepatic ITIH3 also lowered mitochondrial respiration and lipid droplet accumulation. This was accompanied by increased STAT1 signaling and Stat3 expression, both of which are known to protect against NAFLD/NASH. Together, we conclude that ITIH3 plays a unique role in regulating the hepatic lipid profile, DNL, and mitochondrial metabolism, all of which have implications for NAFLD treatment. Our findings indicate hepatokine ITIH3 as a potential biomarker and/or treatment for NAFLD. R00DK120875. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.