Search Results (538)

Metabolic dysfunction-associated steatotic liver disease (MASLD) begins with hepatic lipid accumulation and triggers insulin resistance. Hibiscus leaf extract exhibits antioxidant and anti-atherosclerotic activities, and is rich in (−)-epicatechin gallate (ECG). Despite ECG’s well-known pharmacological activities and its total antioxidant capacity being stronger than that of other catechins, its regulatory effects on MASLD have not been fully described previously. Therefore, this study attempted to evaluate the anti-MASLD potential of ECG isolated from Hibiscus leaves on abnormal lipid and glucose metabolism in hepatocytes. First, oleic acid (OA) was used as an experimental model to induce lipid dysmetabolism in human primary hepatocytes. Treatment with ECG can significantly (p < 0.05) reduce the OA-induced cellular lipid accumulation. Nile red staining revealed, compared to the OA group, the inhibition percentages of 29, 61, and 82% at the tested doses of ECG, respectively. The beneficial effects of ECG were associated with the downregulation of SREBPs/HMGCR and upregulation of PPARα/CPT1 through targeting AMPK. Also, ECG at 0.4 µM produced a significant (p < 0.01) decrease in oxidative stress by 83%, and a marked (p < 0.05) increase in glycogen synthesis by 145% on the OA-exposed hepatocytes with insulin signaling blockade. Mechanistic assays indicated lipid and glucose metabolic homeostasis of ECG might be mediated via regulation of lipogenesis, fatty acid β-oxidation, and insulin resistance, as confirmed by an AMPK inhibitor. These results suggest ECG is a dual modulator of lipid and carbohydrate dysmetabolism in hepatocytes. Full article

Although acetaminophen (APAP) overdose represents the predominant cause of drug-induced acute liver failure (ALF) worldwide and has been extensively studied, the modes of cell death remain debatable and the treatment approach for APAP-induced acute liver failure is still limited. This study investigated the mechanisms of APAP hepatotoxicity in primary mouse hepatocytes (PMHs) by using integrated methods (MTT assay, HPLC analysis for glutathione (GSH), Calcein-AM for labile iron pool detection, confocal microscopy for lipid peroxidation and mitochondrial superoxide measurements, electron microscopy observation, and Western blot analysis for ferritin), focusing on the role of iron dysregulation under oxidative stress. Our results showed that 20 mM APAP treatment induced characteristic features of ferroptosis, including GSH depletion, mitochondrial dysfunction, and iron-dependent lipid peroxidation. Further results showed significant ferritin degradation and subsequent iron releasing. Iron chelator deferoxamine (DFO) and N-acetylcysteine (NAC) could alleviate APAP-induced hepatotoxicity, while autophagy inhibitors did not provide a protective effect. In vitro experiments confirmed that hydrogen peroxide directly damaged ferritin structure, leading to iron releasing, which may aggravate iron-dependent lipid peroxidation. These findings provide evidence that APAP hepatotoxicity involves a self-amplifying cycle of oxidative stress and iron-mediated oxidative damaging, with ferritin destruction playing a key role as a free iron source. This study offers new insights into APAP-induced liver injury beyond conventional cell death classifications, and highlights iron chelation as a potential therapeutic strategy alongside traditional antioxidative treatment with NAC. Full article

MOTS-c is a mitochondrial peptide that plays a crucial role in regulating energy metabolism, gene expression, and immune processes. However, current research primarily focuses on mammals like humans and mice, with no reports on avian MOTS-c. This study aimed to identify and characterize MOTS-c coding sequences across major poultry species through bioinformatics analysis and experimental validation. The alignment results showed high sequence similarity in the MOTS-c coding regions between avian and mammalian species. However, a single nucleotide deletion was identified in avian sequences at the position corresponding to the fourth amino acid residue of mammalian homologs, resulting in divergent downstream amino acid sequences. Despite this deletion, several residues were conserved across species. Phylogenetic analysis of mRNA sequences grouped pigeons with mammals, while protein sequence analysis revealed that poultry and mammals form separate branches, highlighting the divergence between avian and mammalian MOTS-c sequences. Tissue expression profiling demonstrated widespread distribution of chicken MOTS-c across multiple tissues, with the highest expression levels in the heart. Fasting significantly reduced heart MOTS-c expression, suggesting potential metabolic regulatory functions. Functional analysis of MOTS-c in primary hepatocytes revealed significant enrichment of the ribosome, oxidative phosphorylation, and key signaling pathways (PI3K-AKT and JAK-STAT) following 24 hours of treatment. Western blot validation confirmed MOTS-c-mediated activation of the AKT signaling pathway. This study represents the first comprehensive characterization of avian MOTS-c, providing critical insights into its evolutionary conservation and its potential functional roles in gene expression and cellular metabolism. Our findings establish a foundation for further investigation into the functions of mitochondrial-encoded peptides in avian species. Full article

The nuclear receptors pregnane X receptor (PXR), constitutive androstane receptor (CAR), and farnesoid X receptor (FXR) regulate the hepatic metabolism of androstenone, a testicular steroid that accumulates in the fat of intact male pigs and causes boar taint. This study evaluated natural product-derived compounds and conventional agonists targeting these nuclear receptors for their effects on androstenone metabolism in primary hepatocytes from slaughter-weight boars, to assess their potential as treatments for boar taint. Cells were incubated with natural products, conventional agonists, or dimethyl sulfoxide (DMSO; control), then being treated with androstenone. Culture media and cells were analyzed to assess changes in androstenone metabolism and gene expression. UGT1A6 was upregulated by treatments targeting both PXR and CAR and downregulated by FXR agonists. Additionally, PGC1α and NR2F1 were downregulated by compounds targeting PXR/CAR, while FXR and NR0B2 were upregulated and HNF4α downregulated by treatments acting on FXR. The natural products diallyl sulfide (DAS) and (Z)-guggulsterone (GUG) increased overall androstenone metabolism (DAS, GUG) and the production of Phase I androstenol metabolites (DAS), but only in hepatocyte culture replicates that responded positively to these treatments. Although gene expression was similar between positive-response and negative/non-responsive replicates following treatments, negative/non-responsive replicates for several treatments had higher basal expression of UGT2B31, UGT2A1, and SIRT1 and lower basal expression of FXR, PXR, and NR0B1 compared to positive-response replicates. These findings suggest that DAS and GUG may be promising treatments for boar taint, specifically in animals with lower basal rates of androstenone metabolism and higher expression of key nuclear receptors. Full article

Background: Fructus Meliae Toosendan (FMT) is a traditional Chinese medicine used to treat ascariasis; however, its reported hepatotoxicity limits its application. Toosendanin (TSN), as a principal active component, is recognized as the primary toxic ingredient responsible for FMT-induced hepatotoxicity, but the underlying mechanisms remain elusive. Methods: HepG2 cells were treated with TSN and analyzed using Western blotting and qPCR assays for related gene transcription and protein expression. Lipid peroxidation and ferroptosis markers were measured. Balb/c and C57BL/6 mice received various doses of TSN administration, and their liver function was assessed with serum biochemistry and histopathology. Network pharmacology and oxidative lipidomics were performed to identify key targets and metabolites. Results: TSN triggered ferroptosis both in vitro and in vivo, accompanied by the elevated expression of 5-lipoxygenase (ALOX5) and its downstream metabolites. The ALOX5 level modulated hepatocyte sensitivity to TSN-induced ferroptotic damage. An ALOX5 knockdown alleviated TSN-induced liver injury and ferroptosis in vivo. Conclusions: Our study demonstrated that TSN induces hepatotoxicity by facilitating ALOX5-mediated lipid peroxidation, thereby sensitizing cells to ferroptosis. Full article

Metabolic dysfunction-associated steatotic liver disease (MASLD) has become the leading cause of chronic liver disease worldwide, affecting approximately 25–30% of the global adult population and highlighting the urgent need for effective therapeutics and prevention strategies. MASLD is characterized by excessive hepatic lipid accumulation and can progress, in a subset of patients, to metabolic dysfunction-associated steatohepatitis (MASH), a pro-inflammatory and pro-fibrotic condition associated with increased risk of liver cirrhosis and hepatocellular carcinoma. Although the molecular drivers of MASLD progression remain incompletely understood, several key metabolic pathways—such as triglyceride handling, cholesterol catabolism, bile acid metabolism, mitochondrial function, and autophagy—are consistently dysregulated in MASLD livers. This narrative review summarizes primary literature and highlights insights from recent reviews on the multifaceted role of the mRNA-binding protein Human antigen R (HuR) in the post-transcriptional regulation of critical cellular processes, including nutrient metabolism, cell survival, and stress responses. Emerging evidence underscores HuR’s essential role in maintaining liver homeostasis, particularly under metabolic stress conditions characteristic of MASLD, with hepatocyte-specific HuR depletion associated with exacerbated disease severity. Moreover, comorbid conditions such as obesity, type 2 diabetes mellitus, and cardiovascular disease not only exacerbate MASLD progression but also involve HuR dysregulation in extrahepatic tissues, further contributing to liver dysfunction. A deeper understanding of HuR-regulated post-transcriptional networks across metabolic organs may enable the development of targeted therapies aimed at halting or reversing MASLD progression. Full article

The capitula of Chrysanthemum indicum Linné or C. morifolium Ramatuelle (Kikuka in Japanese) are included in several formulae of Kampo medicines (traditional Japanese medicines), such as Chotosan, which is used for headache and dizziness. Luteolin, the principal constituent of C. indicum, has antioxidant and anti-inflammatory activities. However, the effects of other flavonoids on this crude drug have not yet been thoroughly investigated. To evaluate and compare anti-inflammatory effects, we used primary cultured rat hepatocytes, which produce proinflammatory mediators, such as nitric oxide (NO) and proinflammatory cytokines, in response to interleukin (IL)-1β. Eight derivatives of 5,7-dihydroxyflavone were purified and identified in the ethyl acetate-soluble fraction of a C. indicum capitulum extract: luteolin (Compound 1), apigenin (2), diosmetin (3), 5,7-dihydroxy-3′,4′,5′-trimethoxyflavone (4), acacetin (5), eupatilin (6), jaceosidin (7), and 6-methoxytricin (8). Luteolin is the most abundant compound in this fraction. All compounds significantly suppressed NO production in hepatocytes, with apigenin and acacetin showing the greatest efficacy. The comparison of the IC₅₀ values of the inhibition of NO production suggests that substitutions by hydroxyl and methoxy groups at the C-3′ and C-4′ positions of 5,7-dihydroxyflavone may be at least essential for the suppression of NO production. In hepatocytes, acacetin and luteolin decreased the levels of mRNAs encoding inducible nitric oxide synthase (iNOS), proinflammatory cytokines, including tumor necrosis factor, IL-6, and type 1 IL-1 receptor, which regulates inflammatory responses. Based on the comparison of the IC₅₀ values and the content, luteolin, jaceosidin, and diosmetin may be responsible for the anti-inflammatory effects of C. indicum capitula. Full article

Liver cancer has high incidence and mortality rates worldwide, with hepatocellular carcinoma (HCC) being the main histological subtype, accounting for 90% of primary liver cancers. The high mutation rate of viruses combined with endoplasmic reticulum stress may lead to the occurrence of cancer. Hepatitis B virus (HBV) infection is one of the most important pathogenic factors of HCC. The carcinogenic mechanisms of HBV have been widely studied. Among these mechanisms, immune escape and vaccine escape caused by mutations in the HBV S gene have been reported in numerous studies of patients with chronic hepatitis B. In addition, pre-S1/S2 mutations and surface protein truncation mutations may activate multiple signaling pathways. This activation leads to the abnormal proliferation and differentiation of hepatocytes, thereby contributing to the development of HCC. This review aims to integrate the existing literature, summarize the common mutations in the HBV S gene region, and explore the related pathogenic mechanisms. Full article

The spotted longbarbel catfish, Hemibagrus guttatus, a nationally protected Class II species in China, faces increasing threats from habitat degradation. Recently, the spotted longbarbel catfish has gained attention as a promising aquaculture species, not only for its premium flesh quality but also for its potential role in conservation through sustainable captive breeding programs. Ammonia nitrogen (ammonia-N) is a ubiquitous byproduct of intensive farming and serves as the primary environmental stressor confronting aquatic species. Elucidating the ammonia-N tolerance of spotted longbarbel catfish constitutes a critical prerequisite for its successful domestication, which is the aim of this study. We demonstrate that ammonia-N stress significantly decreases the survival rate of spotted longbarbel catfish and induces tissue damage, including gill lamella proliferation, hepatocyte blurring, and renal necrosis. Transcriptomic analysis revealed that ammonia-N stress promotes the expression of genes related to endoplasmic reticulum stress, heat-shock proteins, immune response, and apoptosis, while inhibiting antioxidant-related genes and Wnt-related genes. Enzymatic assays indicate that ammonia-N stress inhibits the activities of multiple antioxidant enzymes, including SOD, CAT, GSH, GSH-Px, and T-AOC. Microbiome analysis showed that ammonia-N stress altered the intestinal microbial community by increasing harmful bacteria (e.g., Vibrio and Aeromonas) and suppressing beneficial bacteria (e.g., Cetobacterium and Lactococcus). These findings highlight the comprehensive negative impacts of ammonia-N on the health of the spotted longbarbel catfish and provide a theoretical basis for optimizing aquaculture conditions to support the sustainable protection and domestication of the spotted longbarbel catfish. Full article

Liver fibrosis is a frequent pathological outcome of long-term liver diseases, arising from sustained damage to the liver. Two main types of liver damage can trigger fibrotic progression: hepatocellular injury, often caused by viral infections, alcohol, or metabolic disorders, and cholestatic injury, associated with impaired bile flow due to autoimmune or congenital conditions. Despite diverse etiologies, liver fibrosis exhibits conserved biological processes, including hepatocyte death, chronic inflammation, disruption of epithelial or endothelial barriers, and excessive deposition of extracellular matrix (ECM) components. These coordinated events reflect the complex interplay among parenchymal damage, immune activation, and fibrogenic signaling pathways. If unresolved, fibrosis may progress to cirrhosis, liver failure, or hepatocellular carcinoma. In the pursuit of non-invasive biomarkers for early detection and monitoring of fibrosis, extracellular vesicles (EVs) have garnered significant attention. Among the diverse cargoes within EVs, microRNAs (miRNAs) have emerged as particularly promising due to their stability, disease-specific expression patterns, and involvement in fibrogenic signaling. This review explores the role of EV-associated miRNAs in liver fibrosis, highlighting key candidates implicated in hepatocellular and cholestatic injury and their clinical potential as diagnostic and prognostic biomarkers, with special focus on MAFLD/MASH, primary sclerosing cholangitis, primary biliary cholangitis, and biliary atresia as representatives. Full article

Changes in hepatic lipoprotein metabolism are responsible for the majority of metabolic dysfunction-associated disorders, including familial hypercholesterolemia (FH), metabolic syndrome (MetS), metabolic dysfunction-associated fatty liver disease (MAFLD), and age-related diseases such as atherosclerosis, a major health burden in modern society. This review aims to advance the understanding of state-of-the-art mechanistic concepts in lipoprotein metabolism, with a particular focus on lipoprotein uptake and secretion and their dysregulation in disease, and to provide a comprehensive overview of experimental models used to study these processes. Human lipoprotein research faces several challenges. First, significant differences in lipoprotein metabolism between humans and other species hinder the reliability of non-human model systems. Additionally, ethical constraints often limit studies on human lipoprotein metabolism using tracers. Lastly, while 2D hepatocyte cell culture systems are widely used, they are commonly of cancerous origins, limiting their physiological relevance and necessitating the use of more physiologically representative models. In this review, we will elaborate on key findings in lipoprotein metabolism, as well as limitations and challenges of currently available study tools, highlighting mechanistic insights throughout discussion of these models. These include human tracer studies, animal studies, 2D tissue culture-based systems derived from cancerous tissue as well as from induced pluripotent stem cells (iPSCs)/embryonic stem cells (ESCs). Finally, we will discuss precision-cut liver slices, liver-on-a-chip models, and, particularly, improved 3D models: (i) spheroids generated from either hepatoma cancer cell lines or primary human hepatocytes and (ii) organoids generated from liver tissues or iPSCs/ESCs. In the last section, we will explore future perspectives on liver-in-a-dish models in studying mechanisms of liver diseases, treatment options, and their applicability in precision medicine approaches. By comparing traditional and advanced models, this review will highlight the future directions of lipoprotein metabolism research, with a focus on the growing potential of 3D liver organoid models. Full article

Earthworms are valued as a dietary protein source in many regions. Earthworm protein can yield bioactive peptides, but enzymatic hydrolysis is inefficient by commercial proteases, and bioactivity development is still inadequate. This study developed a novel efficient method for degrading earthworm protein and investigated the lipid-lowering activity and mechanism of earthworm peptides. It was found that combining autolysis and alcalase exhibited a higher hydrolysis degree of earthworm protein of 43.64 ± 0.78% compared to using autolysis or alcalase only. The hydrolysate significantly reduced lipid accumulation in steatotic hepatocytes. LC-MS/MS results showed that the primary lipid-lowering peptides (EWPs) in the hydrolysate were small molecule peptides with molecular weights of 500–1000 Da and chain lengths of 4–7 amino acid residues. Western blot results demonstrated that EWP regulated the expression of lipid metabolism-related proteins, including APOC3, HMGCR, PCSK9, SREBP1, C/EBP-α, NPC1L1, PPAR-γ, and CYP7A1. Transcriptomic analysis and validation experiments indicated that the lipid-lowering activity of EWP was associated with its suppression of inflammatory factors, such as IL-6. This study presents an efficient enzymatic hydrolysis strategy for earthworm protein utilization, laying the foundation for its application in functional foods such as protein supplements, nutraceutical capsules, hypoallergenic infant formulas, and sports nutrition products. Full article

Marine organism-associated microbes are an important source of structurally diverse and biologically active secondary metabolites exhibiting antimicrobial, anticancer, and anti-inflammatory activities. In this study, we investigated Penicillium brevicompactum MSW10-1, isolated from Hydractinia echinata, a marine invertebrate adapted to extreme intertidal and subtidal environments with variable temperature, salinity, and oxygen conditions. Through a combination of LC/MS-guided chemical analysis and chromatographic purification, eight secondary metabolites were isolated, including brevicolactones A (1) and B (2). The absolute chemical structures of 1 and 2 were determined based on NMR spectroscopic experiments, HR-ESIMS data, and quantum chemical ECD calculations. The isolated compounds (1–8) were evaluated for their ability to inhibit hepatic lipogenesis, a key process in lipid metabolism that is dysregulated in metabolic-dysfunction-associated steatotic liver disease. Furthermore, the inhibitory effects of the isolated compounds on lipid accumulation were further evaluated in primary mouse hepatocytes, using Oil Red O staining. These findings suggested that the isolated compounds may serve as promising candidates for the treatment of metabolic liver diseases associated with lipid dysregulation. Full article

Estrogen plays some important roles in many physiological processes in animals. This hormone is used as a type of medication for humans and animals, including fish, but is associated with serious side effects and environmental persistence, which has led to a growing interest in phytoestrogens as an alternative. Phytoestrogens are compounds derived from plants that are structurally similar to estrogen and may exhibit similar behavior in the body. To date, no studies have investigated the activity of phytoestrogens in relation to the maturation of eels. In the present study, we investigated the effects of ten different plant extracts on vitellogenin (vtg) and estrogen receptor (esr1, esr2) gene expression in eel hepatocytes. As a result, Schisandra and Astragalus extracts induced higher levels of vtg mRNA expression compared to the other extracts. However, increased esr mRNA expression was observed only in the Schisandra and soybean extract-treated groups. The phytoestrogens known to be present in Schisandra and Astragalus were analyzed using HPLC. Schizandrin, gomisin A, and gomisin N were detected in Schisandra extract, and calycosin and formononetin were detected in Astragalus extract. We then examined whether these phytoestrogens could induce vtg mRNA expression in eel hepatocytes. As a result, gomisin N and formononetin significantly induced vtg mRNA expression. In conclusion, among the 10 plant extracts treated in this study, Schisandra and Astragalus extracts induced estrogenic activity in eel hepatocytes. These extracts were found to contain phytoestrogens, with gomisin N and formononetin identified as the primary active components responsible for the observed estrogenic activity in eel hepatocytes. Full article

Liver fibrosis majorly impacts global health, necessitating the development of in vitro models to study disease mechanisms and develop drug therapies. Relevant models should at least include hepatocytes and hepatic stellate cells (HSCs) and ideally use three-dimensional cultures to mimic in vivo conditions. Induced pluripotent stem cells (iPSCs) allow for patient-specific liver modelling, but current models based on iPSC-derived hepatocytes (iHepatocytes) and HSCs (iHSCs) still lack key functions. We developed organoids of iHepatocytes and iHSCs and compared them to HepaRG and primary HSC organoids. RNA sequencing analysis comparison of these cultures identified a potential role for the transcription factor RXRA in hepatocyte differentiation and HSC quiescence. Treating cells with the RXRA ligand 9-cis-retinoic acid (9CRA) promoted iHepatocyte metabolism and iHSC quiescence. In organoids, 9CRA enhanced fibrotic response to TGF-β and acetaminophen, highlighting its potential for refining iPSC-based liver fibrosis models to more faithfully replicate human drug-induced liver injury and fibrotic conditions. Full article