Hepatic Gene Expression Research Articles

Limited preventive effects of empagliflozin against metabolic dysfunction-associated steatotic liver disease in a mouse model of fast food diet.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a highly prevalent disease with limited treatment options. The aim of this study was to evaluate the preventive effects of a sodium-glucose co-transporter (SGLT)-2 inhibitor, empagliflozin, on a dietary mouse model of MASLD. In total, 24 C57BL/6J mice of both sexes were randomly allocated to three groups, as follows: the fast food diet (FFD) group (eight mice, receiving a high-fat, high-cholesterol, high-fructose diet, FFD), the EMPA group (eight mice, fed a FFD with 10mg/kg/d empagliflozin), and the chow diet (eight mice, CD) group. The mice were weighed and blood samples were drawn every 4weeks; after 25weeks the mice were euthanized, at which point liver tissues were histologically evaluated. After 25weeks, there was no significant difference in body weight between the three groups, whereas liver-to-body weight ratio was greater in the EMPA compared to the CD group (p = 0.002). Hepatic fibrosis was marginally different between the three groups (p = 0.045). Fibrosis stage 1 was present in five mice on FFD (62.5%), in one mouse on EMPA (12.5%), and in one mouse on CD (12.5%). Lipogenic, inflammatory, and fibrogenic genes did not differ between the EMPA and FFD groups. Interestingly, mRNA encoding for SGLT-1 and SGLT-2 was detected in the mouse livers. Empagliflozin treatment in mice on a FFD did not result in any significant effects on morphological, biochemical, or histological features or on expression of hepatic genes associated with MASLD compared to those fed a FFD without empagliflozin. The observed effects on mild hepatic fibrosis warrant validation, possibly via studies of longer duration.

Hepatic Gene Expression Changes of Zebrafish Fed Yeast Prebiotic, Yeast Probiotic, Black Soldier Fly Meal, and Butyrate

As global fish consumption rises, improving fish health through immunomodulatory feed ingredients shows promise while also supporting growth performance. This study investigated the effects of yeast prebiotics, probiotics, a postbiotic (butyrate), and black soldier fly larvae (BSFL) meal on fish immune responses. Zebrafish were fed diets containing these ingredients for 63 days and then exposed to either Pseudomonas aeruginosa lipopolysaccharide (LPS) or live Flavobacterium psychrophilum to assess hepatic candidate gene expression and weight gain. No mortalities were observed post-immune challenges, and weight gains were not significantly different across treatments. Liver samples were collected for mRNA analysis, and real-time qPCR was used to evaluate the expression of immune-related genes such as TNF-ɑ, IL-1β, hepcidin, and NF-κB/p65. NF-κB/p65 was upregulated in response to immune challenges, indicating a reaction to both LPS and pathogen exposure. Fish on the BSFL diet showed decreased NF-κB/p65 expression after the pathogen challenge, while probiotic-fed fish had reduced angiopoietin-like 4 (angptl4) levels following LPS exposure. Butyrate supplementation had the most significant impact, downregulating pro-inflammatory cytokines and other immune-related genes, suggesting a protective effect. These findings support the health benefits of BSFL and sodium butyrate during an immune challenge.

Evaluation of black soldier fly (Hermetia illucens) larvae oil as a potential lipid source for largemouth bass (Micropterus salmoides): Growth performance, myofiber development and glucolipid metabolism

Black soldier fly larvae oil (BSFLO) is considered as a by-product of the production process of defatted black soldier fly larvae meal at present, and may show the potential to be used as a lipid source for aquafeeds. In this study, a total of 300 largemouth bass (initial body weight 7.95g) were fed diets containing different levels of BSFLO for 56 d to evaluate its effects on the growth performance, fatty acid composition, antioxidant capacity and glucolipid metabolism. Five isonitrogenous and isolipidic diets were designed with fish oil supplemented feed (FO) as the control diet and then feeds with BSFLO replacing 12.5%, 25%, 50% and 100% of the fish oil (BSFLO12.5, BSFLO25, BSFLO50, BSFLO100) as the treatment diets. No significant changes in weight gain and specific growth rate were observed between groups, but BSFLO100 showed a significant change in feed conversion ratio, higher than the control group (P < 0.05). The muscle and liver C12:0 and ∑n-6 PUFA content increased with the addition of BSFLO, while C20:5n-3, C22:6n-3 and ∑n-3 PUFA content gradually decreased, and significant differences were observed between FO and BSFLO100 (P < 0.05). Expression of hepatic Δ6fad and FABP genes was lower in the FO group and the highest in BSFLO50 and BSFLO100 (P < 0.05). In terms of myofiber development, Dietary BSFLO led to e a progressive increase in myofiber diameter and area, while the expression of smad-2 gene in muscle was significantly reduced in BSFLO25 and BSFLO50 (P < 0.05). Besides, the serum glucose levels were significantly lower in BSFO12.5, BSFLO50 and BSFLO100, and dietary 8% BSFLO (BSFLO100) resulted in a decrease in hepatic glycogen content from 94mgg-1 to 71.78mgg-1, along with the expression of glycolysis-related genes (GK, PK and PFK) and enzyme (PK and PFK) activities (P < 0.05), while the expression of gluconeogenesis-related genes (G6Pase) was significantly increased (P < 0.05). Dietary 4% BSFLO (BSFLO50) increased muscle and liver T-SOD activity and simultaneously reduced muscle MDA content (P < 0.05), which has the best antioxidant properties. One-variable linear regression analysis revealed that various parameters of feed utilization, glucose metabolism, and muscle development in fish were significantly and linearly affected by dietary BSFLO levels (P < 0.05). In summary, if only optimal glucose lowering is considered, 8% BSFLO is recommended. However, if feed utilization efficiency is taken into account, it is recommended that dietary BSFLO be added at no more than 4%.

Sphingosine kinase 2 (SphK2) depletion alters redox metabolism and enhances inflammation in a diet-induced MASH mouse model

Background: Sphingosine-1 phosphate (S1P) is a bioactive lipid molecule that modulates inflammation and hepatic lipid metabolism in MASLD, which affects 1 in 3 people and increases the risk of liver fibrosis and hepatic cancer. S1P can be generated by 2 isoforms of sphingosine kinase (SphK). SphK1 is well-studied in metabolic diseases. In contrast, SphK2 function is not well characterized. Both sphingolipid and redox metabolism dysregulation contribute to MASLD pathologic progression. While SphK2 localizes to both the nucleus and mitochondria, its specific role in early MASH is not well defined. Methods: This study examined SphK2 depletion effects on hepatic redox metabolism, mitochondrial function, and inflammation in a 16-week western diet plus sugar water (WDSW)-induced mouse model of early MASH. Results: WDSW-SphK2 −/− mice exhibit increased hepatic lipid accumulation and hepatic redox dysregulation. In addition, mitochondria-localized cholesterol and S1P precursors were increased. We traced SphK2 −/− -mediated mitochondrial electron transport chain impairment to respiratory complex-IV and found that decreased mitochondrial redox metabolism coincided with increased oxidase gene expression and oxylipin production. Consistent with this relationship, we observed pronounced increases in hepatic inflammatory gene expression, prostaglandin accumulation, and innate immune homing in WDSW-SphK2 −/− mice compared to WDSW-wild-type mice. Conclusions: These studies suggest SphK2-derived S1P maintains hepatic redox metabolism and describe the potential consequences of SphK2 depletion on proinflammatory gene expression, lipid mediator production, and immune infiltration in MASH progression.

Dodecanedioic acid prevents and reverses metabolic-associated liver disease and obesity and ameliorates liver fibrosis in a rodent model of diet-induced obesity.

Dodecanedioic acid (DC12) is a dicarboxylic acid present in protective polymers of fruit and leaves. We explored the effects of DC12 on metabolic dysfunction-associated steatohepatitis (MASH) and obesity. DC12 supplementation (100 mg/kg/day) was added to a high-fat diet (HFD) for 8 weeks in rodents to assess its impact on obesity and MASH prevention. Rats given DC12 experienced significant reductions of weight gain, liver and visceral fat weight, and improved glucose tolerance and insulin sensitivity. Liver histology showed protection against diet-induced MASH, with reduced steatosis, hepatocyte ballooning, and fibrosis. For weight-loss and MASH reversion, rats were fed HFD for 14 weeks, followed by 6 weeks with or without DC12. DC12 supplementation (100 mg/kg/day) led to a significant reduction of weight gain and liver weight. DC12 induced white adipose tissue beiging and reduced adiposity with a decrease of visceral fat. It also improved glucose tolerance, insulin sensitivity, and reduced hepatic gluconeogenic gene expression. Liver histology revealed a significant reduction in steatosis, hepatocyte ballooning, and inflammation as well as fibrosis, indicating MASH reversal. DC12 reduced hepatic lipogenesis enzymes as well as de novo lipogenesis measured by deuterated water and increased fatty acid β-oxidation. Plasma lipid profile showed lower triglycerides and phosphatidylcholines in the DC12 group. Notably, DC12 decreased mINDY expression, the cell membrane Na+-coupled citrate transporter, reducing citrate uptake and de-novo lipogenesis, linking its effects to improved lipid metabolism and reduced steatosis. We found that during the hepatic first pass, half of the DC12 ingested with water was taken up by the liver. The concentration of DC12 in the portal vein falls within the range identified invitro as sufficient to inhibit citrate transport in hepatocytes.

Optimizing selenium-enriched yeast supplementation in laying hens: Enhancing egg quality, selenium concentration in eggs, antioxidant defense, and liver health

This study evaluated the effects of selenium-enriched yeast (SY) supplementation at various levels on health and production parameters in laying hens, including egg production, egg quality, selenium (Se) concentrations in eggs, liver health, serum biochemical markers, antioxidant function, and immune responses. A total of 360 Hy-Line Brown hens (28 weeks old) were randomly assigned to four dietary groups with six replicates of 15 birds each, monitored over a 12-week feeding trial after a two-week acclimatization period. The dietary groups included a control (basal diet without selenium) and three SY-supplemented groups with Se levels of 0.3 mg/kg (SY03), 1.5 mg/kg (SY15), and 6.0 mg/kg (SY60). The results showed no significant effects of dietary SY on laying performance or feed efficiency (P > 0.05). However, the SY15 group showed significant improvements in egg quality, particularly in albumen height, Haugh Unit and yolk color (P < 0.05). Selenium concentrations in eggs, albumen, and yolk increased dose-dependently, with significant differences in the SY-supplemented groups (P < 0.001). Increased activities of liver enzymes including alanine transaminase, alkaline phosphatase, and aspartate transaminase, alongside elevated levels of uric acid were notable in the SY60 group (P < 0.05). In addition, histological analysis revealed significant hepatocyte degeneration and a higher liver organ index (P < 0.05), in the SY60 group. All of which suggests potential liver toxicity at higher selenium levels. Antioxidant capacity of the birds were significantly enhanced due to dietary supplementation of SY as indicated by increased serum levels of total antioxidant capacity, and activities of catalase, glutathione peroxidase, and superoxide dismutase (P < 0.05). Analysis of hepatic genes expression revealed that SY15 supplementation significantly upregulated key antioxidant-related genes (Nrf2, HO-1, CAT, and NQO1) and downregulated Keap1 expression (P < 0.05), suggesting strong activation of the antioxidant defense system. In conclusion, SY supplementation at 1.5 mg/kg improved egg quality, increased Se concentrations in eggs, and enhanced antioxidant capacity without affecting laying performance or liver health. This makes it a balanced approach to improving egg quality and poultry health. However, higher supplementation levels (6.0 mg/kg) resulted in liver damage, underscoring the importance of careful dosage consideration.

Age of Cafeteria Diet Onset Influences Obesity Phenotype in Mice in a Sex-Specific Manner.

We investigated the influence of sex and the age of obesogenic diet initiation on the obesity phenotypes at a later age. C57Bl mice started the Cafeteria Diet (CafD, with increased fat and carbohydrates, ad libitum, from 7 weeks of age (7CafD, pre-puberty) or 17 weeks of age (7CafD, post-puberty) while control C57Bl mice were fed regular chow. At 27 weeks of age, 7CafD males (n = 9) compared to 17CafD males (n = 7) had lower body weight, white adipose tissue (WAT) relative weight, and plasma cholesterol levels, and a higher expression of thermogenic genes in WAT and brown adipose tissue (BAT), and fatty acid oxidation (FAO) and insulin signalling genes in muscles. The 7CafD females (n = 8), compared to 17CafD females (n = 6), had higher plasma triglyceride levels and hepatic glycogen content, but lower insulin sensitivity and hepatic expression of FAO and insulin signalling genes. The 7CafD females, compared to 7CafD males, had more WAT, and a reduced expression of FAO genes in muscles and thermogenic genes in WAT. The 17CafD females, compared to 17CafD males, had lower plasma leptin and insulin levels, and higher insulin sensitivity and expression of insulin signalling genes in the liver and muscles. Thus, the initiation of the obesogenic diet before puberty led to a more adaptive metabolic phenotypes in males, and after puberty, in females.

Prenatal choline supplementation enhances metabolic outcomes with differential impact on DNA methylation in Wistar rat offspring and dams

Choline is an essential nutrient required for proper functioning of organs and serves as a methyl donor. In liver where choline metabolism primarily occurs, glucose homeostasis is regulated through insulin receptor substrates (IRS) 1 and 2. The objective of this research was to determine the role of prenatal choline as a modulator of metabolic health and DNA methylation in liver of offspring and dams. Pregnant Wistar rat dams were fed an AIN-93G diet and received drinking water either with supplemented 0.25% choline (w/w) as choline bitartrate or untreated control. All offspring were weaned to a high-fat diet for 12 weeks. Prenatal choline supplementation led to higher insulin sensitivity in female offspring at weaning as well as lower body weight and food intake and higher insulin sensitivity in female and male adult offspring compared to offspring from untreated dams. Higher hepatic betaine concentrations were observed in dams and female offspring of choline-supplemented dams at weaning and higher glycerophosphocholine in female and male offspring at postweaning compared to the untreated control, suggestive of sustaining different choline pathways. Hepatic gene expression of Irs2 was higher in dams at weaning and female offspring at weaning and postweaning, whereas Irs1 was lower in male offspring at postweaning. Gene-specific DNA methylation of Irs2 was lower in female offspring at postweaning and Irs1 methylation was higher in male offspring at postweaning that exhibited an inverse relationship between methylation and gene expression. In conclusion, prenatal choline supplementation contributes to improved parameters of insulin signaling but these effects varied across time and offspring sex.

Gene expression and DNA methylation changes in response to hypoxia in toxicant-adapted Atlantic killifish (Fundulus heteroclitus).

Coastal fish populations are threatened by multiple anthropogenic impacts, including the accumulation of industrial contaminants and the increasing frequency of hypoxia. Some populations of the Atlantic killifish (Fundulus heteroclitus), like those in New Bedford Harbor (NBH), Massachusetts, have evolved a resistance to dioxin-like polychlorinated biphenyls (PCBs) that may influence their ability to cope with secondary stressors. To address this question, we compared hepatic gene expression and DNA methylation patterns in response to mild or severe hypoxia in killifish from NBH and Scorton Creek (SC), a reference population from a relatively pristine environment. We hypothesized that NBH fish would show altered responses to hypoxia due to trade-offs linked to toxicant resistance. Our results revealed substantial differences between populations. SC fish demonstrated a dose-dependent changes in gene expression in response to hypoxia, while NBH fish exhibited a muted transcriptional response to severe hypoxia. Interestingly, NBH fish showed significant DNA methylation changes in response to hypoxia, while SC fish did not exhibit notable epigenetic alterations. These findings suggest that toxicant-adapted killifish may face trade-offs in their molecular response to environmental stress, potentially impacting their ability to survive severe hypoxia in coastal habitats. Further research is needed to elucidate the functional implications of these epigenetic modifications and their role in adaptive stress responses.

Synergistic Effects of Fructose and Food Preservatives on Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD): From Gut Microbiome Alterations to Hepatic Gene Expression.

Background/Objectives: Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing global health problem closely linked to dietary habits, particularly high fructose consumption. This study investigates the combined effects of fructose and common food preservatives (sodium benzoate, sodium nitrite, and potassium sorbate) on the development and progression of MASLD. Methods: We utilized a human microbiota-associated mouse model, administering 10% fructose with or without preservatives for 11 weeks. Liver histology, hepatic gene expression (microarray analysis), biochemical markers, cytokine profiles, intestinal permeability, and gut microbiome composition (16S rRNA and Internal Transcribed Spacer (ITS) sequencing) were evaluated. Results: Fructose and potassium sorbate synergistically induced liver pathology characterized by increased steatosis, inflammation and fibrosis. These histological changes were associated with elevated liver function markers and altered lipid profiles. The treatments also induced significant changes in both the bacterial and fungal communities and disrupted intestinal barrier function, leading to increased pro-inflammatory responses in the mesenteric lymph nodes. Liver gene expression analysis revealed a wide range of transcriptional changes induced by fructose and modulated by the preservative. Key genes involved in lipid metabolism, oxidative stress, and inflammatory responses were affected. Conclusions: Our findings highlight the complex interactions between dietary components, gut microbiota, and host metabolism in the development of MASLD. The study identifies potential risks associated with the combined consumption of fructose and preservatives, particularly potassium sorbate. Our data reveal new mechanisms that are involved in the development of MASLD and open up a new avenue for the prevention and treatment of MASLD through dietary interventions and the modulation of the microbiome.

Association of antipsychotic drugs on type 2 diabetes mellitus risk in patients with schizophrenia: a population-based cohort and in vitro glucose homeostasis-related gene expression study

BackgroundType 2 diabetes mellitus (T2DM) and its related complications are associated with schizophrenia. However, the relationship between antipsychotic medications (APs) and T2DM risk remains unclear. In this population-based, retrospective cohort study across the country, we investigated schizophrenia and the effect of APs on the risk of T2DM, and glucose homeostasis-related gene expression.MethodsWe used information from the Longitudinal Health Insurance Database of Taiwan for individuals newly diagnosed with schizophrenia (N = 4,606) and a disease-free control cohort (N = 4,606). The differences in rates of development of T2DM between the two cohorts were assessed using a Cox proportional hazards regression model. The effects of APs on the expression of glucose homeostasis-related genes in liver and muscle cell lines were assessed using quantitative real-time PCR.ResultsAfter controlling potential associated confounding factors, the risk of T2DM was higher in the case group than that in the control group [adjusted hazard ratio (aHR), 1.80, p < 0.001]. Moreover, the likelihood of T2DM incidence in patients with schizophrenia without AP treatment (aHR, 2.83) was significantly higher than that in non-schizophrenia controls and those treated with APs (aHR ≤ 0.60). In an in vitro model, most APs did not affect the expression of hepatic gluconeogenesis genes but upregulated those beneficial for glucose homeostasis in muscle cells.ConclusionThis study demonstrates the impact of schizophrenia and APs and the risk of developing T2DM in Asian populations. Unmeasured confounding risk factors for T2DM may not have been included in the study. These findings may help psychiatric practitioners identify patients at risk of developing T2DM.

Sexual Dimorphism in the Immunometabolic Role of Gpr183 in Mice.

Excessive eating and intake of a Western diet negatively affect the intestinal immune system, resulting in compromised glucose homeostasis and lower gut bacterial diversity. The G protein-coupled receptor GPR183 regulates immune cell migration and intestinal immune response and has been associated with tuberculosis, type 1 diabetes, and inflammatory bowel diseases. We hypothesized that with these implications, GPR183 has an important immunometabolic role and investigated this using a global Gpr183 knockout mouse model. Wild-type (WT) and Gpr183-deficient (Gpr183-/-) mice were fed a high-fat, high-sucrose diet (HFSD) for 15 weeks. We investigated changes in weight, body composition, fecal immunoglobulin A (IgA) levels, fecal microbiome, and glucose tolerance before and after the diet. Macrophage infiltration into visceral fat was determined by flow cytometry, and hepatic gene expression was measured. A sexual dimorphism was discovered, whereby female Gpr183-/- mice showed adverse metabolic outcomes compared to WT counterparts with inferior glucose tolerance, lower fecal IgA levels, and increased macrophage infiltration in visceral fat. In contrast, male Gpr183-/- mice had significantly lower fasting blood glucose after diet than male WT mice. Liver gene expression showed reduced inflammation and macrophage markers in Gpr183-/- livers, regardless of sex, while the pancreatic islet area did not differ between the groups. No conclusive differences were found after microbiome sequencing. Gpr183 maintains metabolic homeostasis in female but not in male mice independent of diet. If confirmed in humans, future therapy targeting GPR183 should consider this sexual dimorphism.

Functional remodeling of gut microbiota and liver in laying hens as affected by fasting and refeeding after fasting.

Animals will experience energy deprivation processes such as moulting, clutching, migration and long-distance transportation under natural survival conditions and in production practices, and the body will trigger a series of adaptive metabolic changes during these processes. Fasting and refeeding after fasting can induce remodeling of nutrients and energy metabolism. This study aims to investigate the mechanisms by which the gut microbiota and liver of poultry respond to energy deprivation under specific conditions. Ninety 252-day-old laying hens were randomly divided into 3 groups: (1) fed ad libitum (control group); (2) fasted from day 13 to day 17 (fasting group); (3) fasted from day 1 to day 5, then refed on a specific feeding way (refeeding group). After that, the serum, liver, jejunum tissues, and cecum contents were sampled and sent for metabolome, transcriptome, morphology, and 16S rDNA sequencing analyses, respectively. Results showed that food deprivation not only observably decreased the body weight, liver index, and the villus height and villus/crypt ratio of jejunum, but also significantly changed the gut microbiota compositions, serum metabolic profiles, and the hepatic gene expression patterns of laying hens, whereas these changes were effectively reversed by the following refeeding operation. At the same time, metabolome combined transcriptome analysis revealed that both serum differential metabolites and hepatic differential expressed genes (DEGs) were consistently enriched in the lipid and amino metabolism pathways, and strong correlations were synchronously found between the differential metabolites and both of the differential gut microbial genera and DEGs, suggesting the crosstalks among gut, liver and their resulting serum metabolic products. The results suggested that the organism might coordinate to maintain metabolic homeostasis under energy deprivation through a combination of changes in gut microbial composition and hepatic gene expression.

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) elicited dose-dependent shifts in the murine urinary metabolome associated with hepatic AHR-mediated differential gene expression.

Epidemiological evidence suggests an association between dioxin and dioxin-like compound (DLC) exposure and human liver disease. The prototypical DLC, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), has been shown to induce the progression of reversible hepatic steatosis to steatohepatitis with periportal fibrosis and biliary hyperplasia in mice. Although the effects of TCDD toxicity are mediated by aryl hydrocarbon receptor (AHR) activation, the underlying mechanisms of TCDD-induced hepatotoxicity are unresolved. In the present study, male C57BL/6NCrl mice were gavaged every 4 days for 28 days with 0.03 - 30 μg/kg TCDD and evaluated for liver histopathology and gene expression as well as complementary 1-dimensional proton magnetic resonance (1D- 1H NMR) urinary metabolic profiling. Urinary trimethylamine (TMA), trimethylamine N-oxide (TMAO), and 1-methylnicotinamide (1MN) levels were altered by TCDD at doses ≤ 3 μg/kg; other urinary metabolites, like glycolate, urocanate, and 3-hydroxyisovalerate, were only altered at doses that induced moderate to severe steatohepatitis. Bulk liver RNA-seq data suggested altered urinary metabolites correlated with hepatic differential gene expression corresponding to specific metabolic pathways. In addition to evaluating whether altered urinary metabolites were liver-dependent, published single-nuclear RNA-seq (snRNA-seq), AHR ChIP-seq, and AHR knockout gene expression datasets provide further support for hepatic cell-type and AHR-regulated dependency, respectively. Overall, TCDD-induced liver effects were preceded by and occurred with changes in urinary metabolite levels due to AHR-mediated changes in hepatic gene expression.

ECM1 attenuates hepatic fibrosis by interfering with mediators of latent TGF-β1 activation

ObjectiveExtracellular matrix protein 1 (ECM1) serves as a gatekeeper of hepatic fibrosis by maintaining transforming growth factor-β1 (TGF-β1) in its latent form. ECM1 knockout (KO) causes latent (L) TGF-β1 activation,...

Zhi-Kang-Yin formula attenuates high-fat diet-induced metabolic disorders through modulating gut microbiota-bile acids axis in mice

BackgroundMetabolic disorders have become one of the global medical problems. Due to the complexity of its pathogenesis, there is still no effective treatment. Bile acids (BAs) and gut microbiota (GM) have been proved to be closely related to host metabolism, which could be important targets for metabolic disorders. Zhi-Kang-Yin (ZKY) is a traditional Chinese medicine (TCM) formula developed by the research team according to theory of TCM and has been shown to improve metabolism in clinic. However, the underlying mechanisms are unclear.Aim of the studyThis study aimed to investigate the potential mechanisms of the beneficial effect of ZKY on metabolism.MethodsHigh-fat diet (HFD)-fed mice were treated with and without ZKY. The glucose and lipid metabolism-related indexes were measured. BA profile, GM composition and hepatic transcriptome were then investigated to analyze the changes of BAs, GM, and hepatic gene expression. Moreover, the relationship between GM and BAs was identified with functional gene quantification and ex vivo fermentation experiment.ResultsZKY reduced weight gain and lipid levels in both liver and serum, attenuated hepatic steatosis and improved glucose tolerance in HFD-fed mice. BA profile detection showed that ZKY changed the composition of BAs and increased the proportion of unconjugated BAs and non-12-OH BAs. Hepatic transcriptomic analysis revealed fatty acid metabolism and BA biosynthesis related pathways were regulated. In addition, ZKY significantly changed the structure of GM and upregulated the gene copy number of bacterial bile salt hydrolase. Meanwhile, ZKY directly promoted the growth of Bifidobacterium, which is a well-known bile salt hydrolase-producing genus. The ex vivo co-culture experiment with gut microbiota and BAs demonstrated that the changes of BAs profile in ZKY group were mediated by ZKY-shifted GM, which led to increased expression of genes associated with fatty acid degradation in the liver.ConclusionOur study indicated that the effect of ZKY on improving metabolism is associated with the modulation of GM-BAs axis, especially, by upregulating the abundance of bile salt hydrolase-expression bacteria and increasing the levels of unconjugated BAs. This study indicates that GM-BAs axis might be an important pathway for improving metabolic disorders by ZKY.

Comparative Analysis of Hepatic Gene Expression Profiles in Murine and Porcine Sepsis Models.

Sepsis remains a huge unmet medical need for which no approved drugs, besides antibiotics, are on the market. Despite the clinical impact of sepsis, its molecular mechanism remains inadequately understood. Recent insights have shown that profound hepatic transcriptional reprogramming, leading to fatal metabolic abnormalities, might open a new avenue to treat sepsis. Translation of experimental results from rodents to larger animal models of higher relevance for human physiology, such as pigs, is critical and needs exploration. We performed a comparative analysis of the transcriptome profiles in murine and porcine livers using the following sepsis models: cecal ligation and puncture (CLP) in mice and fecal instillation (FI) in pigs, both of which induce polymicrobial septic peritonitis, and lipopolysaccharide (LPS)-induced endotoxemia in pigs, inducing sterile inflammation. Using bulk RNA sequencing, Metascape pathway analysis, and HOMER transcription factor motif analysis, we were able to identify key genes and pathways affected in septic livers. Conserved upregulated pathways in murine CLP and porcine LPS and FI generally comprise typical inflammatory pathways, except for ER stress, which was only found in the murine CLP model. Conserved pathways downregulated in sepsis comprise almost exclusively metabolic pathways such as monocarboxylic acid, steroid, biological oxidation, and small-molecule catabolism. Even though the upregulated inflammatory pathways were equally induced in the two porcine models, the porcine FI model more closely resembles the metabolic dysfunction observed in the CLP liver compared to the porcine LPS model. This comprehensive comparison focusing on the hepatic responses in mouse CLP versus LPS or FI in pigs shows that the two porcine sepsis models generally resemble quite well the mouse CLP model, with a typical inflammatory signature amongst the upregulated genes and metabolic dysfunction amongst the downregulated genes. The hepatic ER stress observed in the murine model could not be replicated in the porcine models. When studying metabolic dysfunction in the liver upon sepsis, the porcine FI model more closely resembles the mouse CLP model compared to the porcine LPS model.

Metabolic changes in response to food intake in somatostatin 1.1 deficient zebrafish

Somatostatin is a multifunctional hormone with several genes in teleost fishes. A zebrafish CRISPR/Cas9 knockout of the somatostatin 1.1 (sst1.1) with persistent hyperglycaemia and hyperlipidaemia displayed reduced fecundity when fed brine shrimp ad libitum. Here, we investigated the effect of feeding brine shrimp one to three times a day on fecundity and liver transcriptomics of the sst1.1 mutant compared to their wild-type siblings to unravel molecular pathways associated with the phenotype. We find that the sst1.1 deficient zebrafish had high mortality when fed at the highest rate and that in both genotypes, growth and fecundity were proportional to food intake. Although glucose and cholesterol decreased substantially at the lowest level of feeding, they were still higher in the mutant than in the wild-type zebrafish. Furthermore, sst1.1 deficiency had a small but significant effect on the hepatic expression of protein, carbohydrate, and fatty acid biosynthesis genes, contributing to the mutant's diabetic phenotype.

Bacillus CotA laccase improved the intestinal health, amino acid metabolism and hepatic metabolic capacity of Pekin ducks fed naturally contaminated AFB1 diet

BackgroundAflatoxin B1 (AFB1) is a prevalent contaminant in agricultural products, presenting significant risks to animal health. CotA laccase from Bacillus licheniformis has shown significant efficacy in degrading mycotoxins in vitro test. The efficacy of Bacillus CotA laccase in animals, however, remains to be confirmed. A 2 × 2 factorial design was used to investigate the effects of Bacillus CotA laccase level (0 or 1 U/kg), AFB1 challenge (challenged or unchallenged) and their interactions on ducks. The purpose of this study was to evaluate the efficacy of Bacillus CotA laccase in alleviating AFB1 toxicosis of ducks.ResultsBacillus CotA laccase alleviated AFB1-induced declines in growth performance of ducks accompanied by improved average daily gain (ADG) and lower feed/gain ratio (F/G). Bacillus CotA laccase ameliorated AFB1-induced gut barrier dysfunctions and inflammation testified by increasing the jejunal villi height/crypt depth ratio (VH/CD) and the mRNA expression of tight junction protein 1 (TJP1) and zonula occluden-1 (ZO-1) as well as decreasing the expression of inflammation-related genes in the jejunum of ducks. Amino acid metabolome showed that Bacillus CotA laccase ameliorated AFB1-induced amino acid metabolism disorders evidenced by increasing the level of glutamic acid in serum and upregulating the expression of amino acid transport related genes in jejunum of ducks. Bacillus CotA laccase ameliorated AFB1-induced liver injury testified by suppressing oxidative stress, inhibiting apoptosis, and downregulating the expression of hepatic metabolic enzyme related genes of ducks. Moreover, Bacillus CotA laccase degraded AFB1 in digestive tract of ducks, resulting in the reduced absorption level of AFB1 across intestinal epithelium testified by the decreased level of AFB1-DNA adduct in the liver, and the reduced content of AFB1 residues in liver and feces of ducks.ConclusionsBacillus CotA laccase effectively improved the growth performance, intestinal health, amino acid metabolism and hepatic aflatoxin metabolism of ducks fed AFB1 diets, highlighting its potential as an efficient and safe feed enzyme for AFB1 degradation in animal production.Graphical

BCKDH kinase promotes hepatic gluconeogenesis independent of BCKDHA

Elevated circulating branched-chain amino acids (BCAAs) are tightly linked to an increased risk in the development of type 2 diabetes mellitus. The rate limiting enzyme of BCAA catabolism branched-chain α-ketoacid dehydrogenase (BCKDH) is phosphorylated at E1α subunit (BCKDHA) by its kinase (BCKDK) and inactivated. Here, the liver-specific BCKDK or BCKDHA knockout mice displayed normal glucose tolerance and insulin sensitivity. However, knockout of BCKDK in the liver inhibited hepatic glucose production as well as the expression of key gluconeogenic enzymes. No abnormal gluconeogenesis was found in mice lacking hepatic BCKDHA. Consistent with the vivo results, BT2-mediated inhibition or genetic knockdown of BCKDK decreased hepatic glucose production and gluconeogenic gene expressions in primary mouse hepatocytes while BCKDK overexpression exhibited an opposite effect. Whereas, gluconeogenic gene expressions were not altered in BCKDHA-silenced hepatocytes. Mechanistically, BT2 treatment attenuated the interaction of cAMP response element binding protein (CREB) with CREB-binding protein and promoted FOXO1 protein degradation by increasing its ubiquitination. Our findings suggest that BCKDK regulates hepatic gluconeogenesis through CREB and FOXO1 signalings, independent of BCKDHA-mediated BCAA catabolism.