RESUMEN
The natural history of metabolic dysfunction-associated steatotic liver disease (MASLD), previously referred to as non-alcoholic fatty liver disease (NAFLD), is complex and long. A minority of patients develop inflammation and risk progressive fibrosis that can result in cirrhosis. Progression to cirrhosis occurs in 3-5% of patients and often takes more than 20 years. This narrative review presents an update on the natural history of MASLD, discussing studies and risk estimates for progression to severe outcomes, such as decompensated cirrhosis or hepatocellular carcinoma. We highlight the dynamic progression of liver damage, how to identify patients whose disease progresses over time, and how risk factors might be mitigated to reduce the risk for disease progression.
Asunto(s)
Progresión de la Enfermedad , Cirrosis Hepática , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/patología , Factores de Riesgo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/complicaciones , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologíaRESUMEN
Numerous studies highlight the potential of natural antioxidants, such as those found in foods and plants, to prevent or treat nonalcoholic fatty liver disease (NAFLD). Inflammation is a key factor in the progression from high-fat diet-induced NAFLD to nonalcoholic steatohepatitis (NASH). Injured liver cells and immune cells release inflammatory cytokines, activating hepatic stellate cells. These cells acquire a profibrogenic phenotype, leading to extracellular matrix accumulation and fibrosis. Persistent fibrosis can progress to cirrhosis. Fatty infiltration, oxidative stress, and inflammation exacerbate fatty liver diseases. Thus, many plant-derived antioxidants, like silymarin, silibinin, curcumin, resveratrol, berberine, and quercetin, have been extensively studied in experimental models and clinical patients with NAFLD. Experimentally, these compounds have shown beneficial effects in reducing lipid accumulation, oxidative stress, and inflammatory markers by modulating the ERK, NF-κB, AMPKα, and PPARγ pathways. They also help decrease metabolic endotoxemia, intestinal permeability, and gut inflammation. Clinically, silymarin and silibinin have been found to reduce transaminase levels, while resveratrol and curcumin help alleviate inflammation in NAFLD patients. However, these phytocompounds exhibit poor water solubility, leading to low oral bioavailability and hindering their biological efficacy. Additionally, inconclusive clinical results highlight the need for further trials with larger populations, longer durations, and standardized protocols.
Asunto(s)
Suplementos Dietéticos , Inflamación , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Inflamación/patología , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , AnimalesRESUMEN
Non-alcoholic fatty liver disease (NAFLD) and myocardial infarction (MI) are two major health burdens with significant prevalence and mortality. This study aimed to explore the co-expressed genes to understand the relationship between NAFLD and MI and identify potential crucial biomarkers of NAFLD-related MI using bioinformatics and machine learning. Functional enrichment analysis was conducted, a co-protein-protein interaction (PPI) network diagram was constructed, and support vector machine-recursive feature elimination (SVM-RFE) and least absolute shrinkage and selection operator (LASSO) techniques were employed to identify one differentially expressed gene (DEG), Thrombospondin 1 (THBS1). THBS1 demonstrated strong performance in distinguishing NAFLD patients (AUC = 0.981) and MI patients (AUC = 0.900). Immuno-infiltration analysis revealed significantly lower CD8+ T cells and higher neutrophil levels in patients with NAFLD and MI. CD8+ T cells and neutrophils were effective in distinguishing NAFLD/MI from healthy controls. Correlation analysis showed that THBS1 was positively correlated with CCR (chemokine receptor), MHC class (major histocompatibility complex class), neutrophils, parainflammation, and Tfh (follicular helper T cells), and negatively correlated with CD8+ T cells, cytolytic activity, and TIL (tumor-infiltrating lymphocytes) in NAFLD and MI patients. THBS1 emerged as a novel biomarker for diagnosing NAFLD/MI in comparison to healthy controls. The results indicate that CD8+ T cells and neutrophils could serve as inflammatory immune features for differentiating patients with NAFLD/MI from healthy individuals.
Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Trombospondina 1 , Humanos , Enfermedad del Hígado Graso no Alcohólico/inmunología , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Trombospondina 1/genética , Trombospondina 1/metabolismo , Infarto del Miocardio/inmunología , Infarto del Miocardio/metabolismo , Infarto del Miocardio/genética , Máquina de Vectores de Soporte , Biomarcadores/metabolismo , Biomarcadores/análisisRESUMEN
Abnormal SUMOylation is implicated in non-alcoholic fatty liver disease (NAFLD) progression. Forkhead box protein A1 (FoxA1) has been shown to protect liver from steatosis, which was down-regulated in NAFLD. This study elucidated the role of FoxA1 deSUMOylation in NAFLD. NAFLD models were established in high-fat diet (HFD)-induced mice and palmitate acid (PAL)-treated hepatocytes. Hepatic steatosis was evaluated by biochemical and histological methods. Lipid droplet formation was determined by BODIPY and Oil red O staining. Target molecule levels were analyzed by RT-qPCR, Western blotting, and immunohistochemistry staining. SUMOylation of FoxA1 was determined by Ni-NTA pull-down assay and SUMOylation assay Ultra Kit. Protein interaction and ubiquitination were detected by Co-IP. Gene transcription was assessed by ChIP and dual luciferase reporter assays. Liver FoxA1 knockout mice developed severe liver steatosis, which could be ameliorated by sirtuin 6 (Sirt6) overexpression. Nutritional stresses reduced Sumo2/3-mediated FoxA1 SUMOylation at lysine residue K6, which promoted lipid droplet formation by repressing fatty acid ß-oxidation. Moreover, Sirt6 was a target gene of FoxA1, and Sirt6 transcription activity was restrained by deSUMOylation of FoxA1 at site K6. Furthermore, nutritional stresses-induced deSUMOylation of FoxA1 promoted the ubiquitination and degradation of FoxA1 with assistance of murine double minute 2 (Mdm2). Finally, activating FoxA1 SUMOylation delayed the progression of NAFLD in mice. DeSUMOylation of FoxA1 at K6 promotes FoxA1 degradation and then inhibits Sirt6 transcription, thereby suppressing fatty acid ß-oxidation and facilitating NAFLD development. Our findings suggest that FoxA1 SUMOylation activation might be a promising therapeutic strategy for NAFLD.
Asunto(s)
Regulación hacia Abajo , Factor Nuclear 3-alfa del Hepatocito , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico , Sirtuinas , Sumoilación , Animales , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Factor Nuclear 3-alfa del Hepatocito/metabolismo , Factor Nuclear 3-alfa del Hepatocito/genética , Ratones , Humanos , Sirtuinas/metabolismo , Sirtuinas/genética , Masculino , Ratones Endogámicos C57BL , Dieta Alta en Grasa , Modelos Animales de EnfermedadRESUMEN
Background: Nonalcoholic fatty liver disease (NAFLD) is a prevalent metabolic disorder strongly linked to type 2 diabetes mellitus (T2DM). Understanding the predictive value of lipid parameters in identifying abnormal glucose metabolism in NAFLD patients is crucial for early intervention. Methods: This study analyzed data from the National Health and Nutrition Examination Survey(NHANES) database (2017-2020) involving 1066 NAFLD patients. Participants were categorized into three groups: T2DM (n=414), prediabetes mellitus (pre-DM) (n=507), and normoglycemia (NG) (n=145). Traditional lipid parameters [triglycerides (TG) and high-density lipoprotein cholesterol (HDL-C)] and nontraditional lipid parameters [atherogenic index of plasma (AIP), residual cholesterol (RC), and non-high-density lipoprotein cholesterol (non-HDL-C)] were evaluated for their association with T2DM and pre-DM. Results: Elevated TG levels were significantly associated with an increased risk of T2DM and pre-DM, whereas high HDL-C demonstrated a protective effect. Among nontraditional lipid parameters, increased AIP and RC were most strongly associated with T2DM risk, while high non-HDL-C was best associated with the development of pre-DM. Stratified analyses revealed that these associations were stronger in younger, non-obese, smoking, and female NAFLD patients. Conclusion: Nontraditional lipid parameters, particularly AIP and RC, show superior predictive value over traditional lipid parameters in identifying abnormal glucose metabolism in NAFLD patients. Incorporating these novel biomarkers into clinical practice could enhance early detection and prevention strategies for T2DM and pre-DM in this high-risk population.
Asunto(s)
Diabetes Mellitus Tipo 2 , Enfermedad del Hígado Graso no Alcohólico , Encuestas Nutricionales , Estado Prediabético , Humanos , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Enfermedad del Hígado Graso no Alcohólico/sangre , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Femenino , Masculino , Estado Prediabético/sangre , Estado Prediabético/epidemiología , Estado Prediabético/metabolismo , Persona de Mediana Edad , Adulto , Factores de Riesgo , Lípidos/sangre , Biomarcadores/sangre , Anciano , Estudios Transversales , Glucemia/metabolismo , Glucemia/análisisRESUMEN
Non-alcoholic fatty liver disease (NAFLD) is a rising global burden, affecting one in four adults. Despite the increasing prevalence of NAFLD, the exact cellular and molecular mechanisms remain unclear, and effective therapeutic strategies are still limited. In vitro models of NAFLD are critical to understanding the pathogenesis and searching for effective therapies; thus, we evaluated the effects of free fatty acids (FFAs) on NAFLD hallmarks and their association with the modulation of Annexin A2 (ANXA2) and Keratin 17 (KRT17) in HepG2 cells. Our results show that oleic and palmitic acids can differentially induce intracellular lipid accumulation, cell death, and promote oxidative stress by increasing lipid peroxidation, protein carbonylation, and antioxidant defense depletion. Moreover, a markedly increased expression of inflammatory cytokines demonstrated the activation of inflammation pathways associated with lipotoxicity and oxidative stress. ANXA2 overexpression and KRT17 nuclear translocation were also observed, supporting the role of both molecules in the progression of liver disease. Taken together, these data provide insights into the interplay between ANXA2 and KRT17 in NAFLD, paving the way for understanding molecular mechanisms involved with the disease and developing new therapeutic strategies.
Asunto(s)
Anexina A2 , Ácidos Grasos no Esterificados , Enfermedad del Hígado Graso no Alcohólico , Estrés Oxidativo , Humanos , Anexina A2/metabolismo , Anexina A2/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo/efectos de los fármacos , Células Hep G2 , Ácidos Grasos no Esterificados/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacosRESUMEN
Obesity-related metabolic disorders, including diabetes, non-alcoholic fatty liver disease (NAFLD), and cardiovascular disease, increasingly threaten global health. Uncontrolled inflammation is a key pathophysiological factor in many of these conditions. In the human body, inflammatory responses generate specialized pro-resolving mediators (SPMs), which are crucial for resolving inflammation and restoring tissue balance. SPMs derived from omega-3 polyunsaturated fatty acids (n-3 PUFAs) such as resolvins, protectins, and maresins hold promise in attenuating the chronic inflammatory diseases associated with lipid metabolism disorders. Recent research has highlighted the therapeutic potential of n-3 PUFA-derived metabolites in addressing these metabolic disorders. However, the understanding of the pharmacological aspects of SPMs, particularly in obesity-related metabolic disorders, remains limited. This review comprehensively summarizes recent advances in understanding the role of SPMs in resolving metabolic disorders, based on studies in animal models and humans. These studies indicate that SPMs have potential as therapeutic targets for combating obesity, as well as offering insights into their mechanisms of action.
Asunto(s)
Enfermedades Metabólicas , Obesidad , Humanos , Obesidad/metabolismo , Animales , Enfermedades Metabólicas/metabolismo , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-3/uso terapéutico , Mediadores de Inflamación/metabolismo , Inflamación/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológicoRESUMEN
Non-alcoholic fatty liver disease (NAFLD) is one of the most common metabolic diseases encountered in clinical practice, which is characterized by the excessive accumulation of triglycerides (steatosis), and a variety of metabolic abnormalities including lipid metabolism and bile acid metabolism are closely related to NAFLD. In China, Gynostemma pentaphyllum is used as functional food and Chinese medicine to treat various diseases, especially NAFLD, for a long time. However, the active components that exert the main therapeutic effects and their mechanisms remain unclear. In this study, Gypensapogenin A was isolated from the total saponins of G. pentaphyllum and prepared as a liposomal delivery system. Gypensapogenin A liposomes could activate FXR, inhibit the expression of CYP7A1 and CYP8B1, increase the expression of CYP27A1, modulate the ratio of CA and CDCA, decrease the content of CA, and increase the content of CDCA, thus forming a virtuous cycle of activating FXR to play a role in lowering blood lipid levels.
Asunto(s)
Gynostemma , Metabolismo de los Lípidos , Liposomas , Receptores Citoplasmáticos y Nucleares , Receptores Citoplasmáticos y Nucleares/metabolismo , Liposomas/química , Metabolismo de los Lípidos/efectos de los fármacos , Humanos , Animales , Gynostemma/química , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Saponinas/farmacología , Saponinas/química , Células Hep G2 , Ratones , Ácidos y Sales Biliares/metabolismo , Hepatocitos/metabolismo , Hepatocitos/efectos de los fármacosRESUMEN
AIMS: Nonalcoholic steatohepatitis (NASH) is the severe subtype of nonalcoholic fatty diseases (NAFLD) with few options for treatment. Patients with NASH exhibit partial responses to the current therapeutics and adverse effects. Identification of the binding proteins for the drugs is essential to understanding the mechanism and adverse effects of the drugs and fuels the discovery of potent and safe drugs. This paper aims to critically discuss recent advances in covalent and noncovalent approaches for identifying binding proteins that mediate NASH progression, along with an in-depth analysis of the mechanisms by which these targets regulate NASH. MATERIALS AND METHODS: A literature search was conducted to identify the relevant studies in the database of PubMed and the American Chemical Society. The search covered articles published from January 1990 to July 2024, using the search terms with keywords such as NASH, benzophenone, diazirine, photo-affinity labeling, thermal protein profiling, CETSA, target identification. KEY FINDINGS: The covalent approaches utilize drugs modified with diazirine and benzophenone to covalently crosslink with the target proteins, which facilitates the purification and identification of target proteins. In addition, they map the binding sites in the target proteins. By contrast, noncovalent approaches identify the binding targets of unmodified drugs in the intact cell proteome. The advantages and limitations of both approaches have been compared, along with a comprehensive analysis of recent innovations that further enhance the efficiency and specificity. SIGNIFICANCE: The analyses of the applicability of these approaches provide novel tools to delineate NASH pathogenesis and promote drug discovery.
Asunto(s)
Descubrimiento de Drogas , Enfermedad del Hígado Graso no Alcohólico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Humanos , Descubrimiento de Drogas/métodos , Animales , Bibliotecas de Moléculas Pequeñas/farmacología , Unión Proteica , Proteínas/metabolismoRESUMEN
Fatty acid-binding protein 1 (FABP1) plays an important role in regulating fatty acid metabolism in liver, which is a potential therapeutic target for diseases such as non-alcoholic fatty liver disease (NAFLD). However, the underlying mechanisms are not well defined. Using complementary experimental models, we discovered FABP1 induction in hepatocytes as a primary mediator of lipogenesis when exposed to fatty acids, especially saturated fatty acids (SFAs). In the feeding trial, palm oil led to excess lipid accumulation in the liver of large yellow croaker (Larimichthys crocea), accompanied by significant induction of FABP1. In cultured cells, palmitic acid (PA), a kind of SFA, triggered the fabp1 expression and increased triglyceride (TG) contents. Knockdown of FABP1 dampened PA-induced TG accumulation through mitigated lipogenesis. The overexpression of FABP1 showed the opposite result. Furthermore, the inactivation of FABP1 led to induction in insulin-induced gene 1 (INSIG1) expression, which attenuated the processing of sterol regulatory element-binding protein 1 (SREBP1) by down-regulating the nuclear-localized SREBP1. These results revealed a previously unrecognized function of FABP1 in response to PA, providing additional evidence for targeting FABP1 in the treatment of NAFLD caused by SFA.
Asunto(s)
Proteínas de Unión a Ácidos Grasos , Hepatocitos , Lipogénesis , Perciformes , Proteína 1 de Unión a los Elementos Reguladores de Esteroles , Animales , Hepatocitos/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Perciformes/metabolismo , Perciformes/genética , Proteínas de Unión a Ácidos Grasos/genética , Proteínas de Unión a Ácidos Grasos/metabolismo , Triglicéridos/metabolismo , Proteínas de Peces/genética , Proteínas de Peces/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ácido Palmítico/farmacología , Células CultivadasRESUMEN
Non-alcoholic Fatty Liver Disease (NAFLD), noted for its widespread prevalence among adults, has become the leading chronic liver condition globally. Simultaneously, the annual disease burden, particularly liver cirrhosis caused by NAFLD, has increased significantly. Neutrophil Extracellular Traps (NETs) play a crucial role in the progression of this disease and are key to the pathogenesis of NAFLD. However, research into the specific roles of NETs-related genes in NAFLD is still a field requiring thorough investigation. Utilizing techniques like AddModuleScore, ssGSEA, and WGCNA, our team conducted gene screening to identify the genes linked to NETs in both single-cell and bulk transcriptomics. Using algorithms including Random Forest, Support Vector Machine, Least Absolute Shrinkage, and Selection Operator, we identified ZFP36L2 and PHLDA1 as key hub genes. The pivotal role of these genes in NAFLD diagnosis was confirmed using the training dataset GSE164760. This study identified 116 genes linked to NETs across single-cell and bulk transcriptomic analyses. These genes demonstrated enrichment in immune and metabolic pathways. Additionally, two NETs-related hub genes, PHLDA1 and ZFP36L2, were selected through machine learning for integration into a prognostic model. These hub genes play roles in inflammatory and metabolic processes. scRNA-seq results showed variations in cellular communication among cells with different expression patterns of these key genes. In conclusion, this study explored the molecular characteristics of NETs-associated genes in NAFLD. It identified two potential biomarkers and analyzed their roles in the hepatic microenvironment. These discoveries could aid in NAFLD diagnosis and management, with the ultimate goal of enhancing patient outcomes.
Asunto(s)
Biomarcadores , Trampas Extracelulares , Aprendizaje Automático , Enfermedad del Hígado Graso no Alcohólico , Análisis de la Célula Individual , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Humanos , Análisis de la Célula Individual/métodos , Trampas Extracelulares/metabolismo , Biomarcadores/metabolismo , Neutrófilos/metabolismo , Transcriptoma , Perfilación de la Expresión GénicaRESUMEN
Proinflammatory hepatic macrophage activation plays a key role in the development of nonalcoholic steatohepatitis (NASH). This involves increased embryonic hepatic Kupffer cell (KC) death, facilitating the replacement of KCs with bone marrow-derived recruited hepatic macrophages (RHMs) that highly express proinflammatory genes. Moreover, phago/efferocytic activity of KCs is diminished in NASH, enhancing liver inflammation. However, the molecular mechanisms underlying these changes in KCs are not known. Here, we show that hypoxia-inducible factor 2α (HIF-2α) mediates NASH-associated decreased KC growth and efferocytosis by enhancing lysosomal stress. At the molecular level, HIF-2α stimulated mammalian target of rapamycin (mTOR)- and extracellular signal-regulated kinase-dependent inhibitory transcription factor EB (TFEB) phosphorylation, leading to decreased lysosomal and phagocytic gene expression. With increased metabolic stress and phago/efferocytic burden in NASH, these changes were sufficient to increase lysosomal stress, causing decreased efferocytosis and lysosomal cell death. Of interest, HIF-2α-dependent TFEB regulation only occurred in KCs but not RHMs. Instead, in RHMs, HIF-2α promoted mitochondrial reactive oxygen species production and proinflammatory activation by increasing ANT2 expression and mitochondrial permeability transition. Consequently, myeloid lineage-specific or KC-specific HIF-2α depletion or the inhibition of mTOR-dependent TFEB inhibition using antisense oligonucleotide treatment protected against the development of NASH in mice. Moreover, treatment with an HIF-2α-specific inhibitor reduced inflammatory and fibrogenic gene expression in human liver spheroids cultured under a NASH-like condition. Together, our results suggest that macrophage subtype-specific effects of HIF-2α collectively contribute to the proinflammatory activation of liver macrophages, leading to the development of NASH.
Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Macrófagos del Hígado , Hígado , Activación de Macrófagos , Enfermedad del Hígado Graso no Alcohólico , Macrófagos del Hígado/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Hígado/metabolismo , Hígado/patología , Ratones , Muerte Celular , Lisosomas/metabolismo , Fagocitosis , Humanos , Especies Reactivas de Oxígeno/metabolismo , Inflamación/patología , Inflamación/metabolismo , Ratones Endogámicos C57BL , Serina-Treonina Quinasas TOR/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Macrófagos/metabolismo , Mitocondrias/metabolismoRESUMEN
Metabolic dysfunction-associated steatotic liver disease (MASLD) is a prevalent chronic liver condition worldwide, demanding further investigation into its pathogenesis. Circular RNAs (circRNAs) are emerging as pivotal regulators in MASLD processes, yet their pathological implications in MASLD remain poorly understood. This study focused on elucidating the role of circular RNA ribonucleotide reductase subunit M2 (circRRM2) in MASLD progression. In this study, we used both in vitro and in vivo MASLD models using long-chain-free fatty acid (FFA)-treated hepatocytes and high-fat diet (HFD)-induced MASLD in mice, respectively. We determined the expression patterns of circRRM2, microRNA-142-5p (miR-142-5p), and neuregulin 1 (NRG1) in livers of MASLD-afflicted mice and MASLD hepatocytes by RT-qPCR. Dual-luciferase reporter assays verified the binding relationships among circRRM2, miR-142-5p, and NRG1. We conducted further analyses of their roles in MASLD hepatocytes and modulated circRRM2, miR-142-5p, and NRG1 expression in vitro by transfection. Our findings were validated in vivo. The results demonstrated reduced levels of circRRM2 and NRG1, along with elevated miR-142-5p expression in MASLD livers and hepatocytes. Overexpression of circRRM2 downregulated lipogenesis-related genes and decreased triglycerides accumulation in livers of MASLD mice. MiR-142-5p, which interacts with circRRM2, effectively counteracted the effects of circRRM2 in MASLD hepatocytes. Furthermore, NRG1 was identified as a miR-142-5p target, and its overexpression mitigated the regulatory impact of miR-142-5p on MASLD hepatocytes. In conclusion, circRRM2, via its role as a miR-142-5p sponge, upregulating NRG1, possibly influenced triglycerides accumulation in both in vitro and in vivo MASLD models.NEW & NOTEWORTHY CircRRM2 expression was downregulated in free fatty acid (FFA)-challenged hepatocytes and high-fat diet (HFD) fed mice. Overexpressed circular RNA ribonucleotide reductase subunit M2 (circRRM2) attenuated metabolic dysfunction-associated steatotic liver disease (MASLD) development by suppressing FFA-induced triglycerides accumulation. CircRRM2 targeted microRNA-142-5p (miR-142-5p), which served as an upstream inhibitor of neuregulin 1 (NRG1) and collaboratively regulated MASLD progression.
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Dieta Alta en Grasa , Hepatocitos , MicroARNs , Neurregulina-1 , ARN Circular , Animales , MicroARNs/metabolismo , MicroARNs/genética , Ratones , Hepatocitos/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Masculino , Neurregulina-1/genética , Neurregulina-1/metabolismo , Ratones Endogámicos C57BL , Hígado Graso/metabolismo , Hígado Graso/genética , Humanos , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ribonucleósido Difosfato ReductasaRESUMEN
Nonalcoholic fatty liver disease (NAFLD) is a chronic liver disease characterized by the accumulation of fat in the liver in the absence of excessive alcohol consumption or a secondary cause of hepatic steatosis. The prevalence of NAFLD is increasing worldwide and its management has become a public health concern. Animal models are traditionally used to elucidate disease mechanisms and identify potential drug targets; however, their translational aspects in human diseases have not been fully established. This study aimed to clarify the utility of animal models for translational research by assessing their relevance to human diseases using gene expression analysis. Weighted gene co-expression network analysis of liver tissues from Western diet (WD)-induced NAFLD mice was performed to identify the modules associated with disease progression. Moreover, the similarity of the gene co-expression network across species was evaluated using module preservation analysis. Nineteen disease-associated modules were identified. The brown module was positively associated with disease severity, and functional analyses indicated that it may be involved in inflammatory responses in immune cells. Moreover, the gene co-expression network of the brown module was highly preserved in human NAFLD liver gene expression datasets. These results indicate that WD-induced NAFLD mice have similar gene co-expression networks (especially genes associated with inflammatory responses) to humans and are thought to be a useful experimental tool for preclinical research on NAFLD. Keywords: Nonalcoholic fatty liver disease (NAFLD), Weighted gene co-expression network analysis (WGCNA), Western diet (WD).
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Dieta Occidental , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico , Transcriptoma , Animales , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/patología , Dieta Occidental/efectos adversos , Ratones , Humanos , Masculino , Hígado/metabolismo , Hígado/patología , Perfilación de la Expresión Génica/métodosRESUMEN
Metabolic dysfunction-associated fatty liver disease (MAFLD) is a common liver disease associated with obesity and is caused by the accumulation of ectopic fat without alcohol consumption. Coxsackievirus and adenovirus receptor (CAR) are vital for cardiac myocyte-intercalated discs and endothelial cell-to-cell tight junctions. CAR has also been reported to be associated with obesity and high blood pressure. However, its function in the liver is still not well understood. The liver of obese mice exhibit elevated CAR mRNA and protein levels. Furthermore, in the liver of patients with non-alcoholic steatohepatitis, CAR is reduced in hepatocyte cell-cell junctions compared to normal levels. We generated liver-specific CAR knockout (KO) mice to investigate the role of CAR in the liver. Body and liver weights were not different between wild-type (WT) and KO mice fed a paired or high-fat diet (HFD). However, HFD induced significant liver damage and lipid accumulation in CAR KO mice compared with WT mice. Additionally, inflammatory cytokines transcription, hepatic permeability, and macrophage recruitment considerably increased in CAR KO mice. We identified a new interaction partner of CAR using a protein pull-down assay and mass spectrometry. Apolipoprotein B mRNA editing enzyme catalytic polypeptide-like 3C (APOBEC3C) demonstrated a complex relationship with CAR, and hepatic CAR expression tightly regulated its level. Moreover, Apolipoprotein B (ApoB) and Low-density lipoprotein receptor (LDLR) levels correlated with APOBEC3C expression in the liver of CAR KO mice, suggesting that CAR may regulate lipid accumulation by controlling APOBEC3C activity. In this study, we showed that hepatic CAR deficiency increased cell-to-cell permeability. In addition, CAR deletion significantly increased hepatic lipid accumulation by inducing ApoB and LDLR expression. Although the underlying mechanism is unclear, CARs may be a target for the development of novel therapies for MAFLD.
Asunto(s)
Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus , Hígado , Ratones Noqueados , Animales , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus/metabolismo , Proteína de la Membrana Similar al Receptor de Coxsackie y Adenovirus/genética , Hígado/metabolismo , Hígado/patología , Ratones , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Dieta Alta en Grasa/efectos adversos , Humanos , Hepatocitos/metabolismo , Masculino , Ratones Endogámicos C57BLRESUMEN
The gut microbiota constitutes a complex ecosystem, comprising trillions of microbes that have co-evolved with their host over hundreds of millions of years. Over the past decade, a growing body of knowledge has underscored the intricate connections among diet, gut microbiota, and human health. Bioactive polysaccharides (BPs) from natural sources like medicinal plants, seaweeds, and fungi have diverse biological functions including antioxidant, immunoregulatory, and metabolic activities. Their effects are closely tied to the gut microbiota, which metabolizes BPs into health-influencing compounds. Understanding how BPs and gut microbiota interact is critical for harnessing their potential health benefits. This review provides an overview of the human gut microbiota, focusing on its role in metabolic diseases like obesity, type II diabetes mellitus, non-alcoholic fatty liver disease, and cardiovascular diseases. It explores the basic characteristics of several BPs and their impact on gut microbiota. Given their significance for human health, we summarize the biological functions of these BPs, particularly in terms of immunoregulatory activities, blood sugar, and hypolipidemic effect, thus providing a valuable reference for understanding the potential benefits of natural BPs in treating metabolic diseases. These properties make BPs promising agents for preventing and treating metabolic diseases. The comprehensive understanding of the mechanisms by which BPs exert their effects through gut microbiota opens new avenues for developing targeted therapies to improve metabolic health.
Asunto(s)
Microbioma Gastrointestinal , Enfermedades Metabólicas , Polisacáridos , Humanos , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/fisiología , Polisacáridos/farmacología , Enfermedades Metabólicas/microbiología , Enfermedades Metabólicas/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/microbiología , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Diabetes Mellitus Tipo 2/microbiología , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Animales , Obesidad/microbiología , Obesidad/tratamiento farmacológico , Obesidad/metabolismoRESUMEN
Metabolic dysfunction-associated steatotic liver disease (MASLD), previously known as non-alcoholic fatty liver disease (NAFLD), is a seriously increasing liver disorder affecting nearly 32% of adults globally. Hepatic triglycerides (TG) accumulation is the hallmark of MASLD, which results from dysregulated lipid and fatty acid uptake, increased de novo lipogenesis (DNL), and decreased lipid removal. More recently, selective autophagy of lipid droplets (LDs), termed lipophagy, has emerged to be closely associated with disrupted hepatic lipid homeostasis. Recent studies have indicated that a series of natural products have shown promise as an alternative approach in attenuating MASLD via regulating lipophagy in vivo and in vitro. Therefore, lipophagy could be a new approach for natural products to be used to improve MASLD. This article aims to provide a comprehensive overview on the interrelationship between dysregulated lipid metabolism, lipophagy, and MASLD pathogenesis. In addition, the role of some natural products as lipophagy modulators and their impact on MASLD will be discussed.
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Autofagia , Productos Biológicos , Metabolismo de los Lípidos , Hígado , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Autofagia/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Hígado/metabolismo , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Animales , Lipogénesis/efectos de los fármacos , Triglicéridos/metabolismo , Gotas Lipídicas/metabolismoRESUMEN
Non-alcoholic fatty liver disease (NAFLD) is a prominent cause of chronic liver disease worldwide. Spermidine (SPD), a naturally occurring polyamine, has shown potential in alleviating the accumulation of hepatic lipids and reducing NAFLD symptoms in overweight mice. Nonetheless, the specific mechanisms through which SPD exerts its effects remain largely unknown. This study seeks to explore the protective effects of SPD on NAFLD and to clarify the underlying mechanisms. An in vitro model of NAFLD was established by inducing steatosis in AML-12 cells through the use of free fatty acids (FFAs). Our experimental results demonstrate that SPD significantly reduces NAFLD development induced by FFAs. This reduction is primarily achieved through the inhibition of cellular ferroptosis, as evidenced by decreased levels of Fe2+, malondialdehyde (MDA), and reactive oxygen species (ROS). Additionally, SPD was found to enhance cellular activity and ameliorate mitochondrial dysfunction and oxidative stress caused by FFA exposure. Further mechanistic studies have revealed that SPD upregulates the expression of solute transporter family 7a member 11 (SLC7A11), glutamate-cysteine ligase modifier subunit (GCLM), and glutathione peroxidase (GPX4). This upregulation is mediated by the activation of activating transcription factor 4 (ATF4). Knockdown experiments of ATF4 confirmed that its inhibition reverses the upregulation of SLC7A11, GCLM, and GPX4, thereby negating the protective effects of SPD. In conclusion, our findings suggest that SPD mitigates NAFLD by modulating the ATF4/SLC7A11/GCLM/GPX4 signaling pathway, resulting in the suppression of ferroptosis and the improvement of cellular health. These insights provide a novel molecular mechanism and identify potential therapeutic targets for the treatment of NAFLD.
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Factor de Transcripción Activador 4 , Sistema de Transporte de Aminoácidos y+ , Ferroptosis , Fosfolípido Hidroperóxido Glutatión Peroxidasa , Transducción de Señal , Espermidina , Ferroptosis/efectos de los fármacos , Espermidina/farmacología , Espermidina/metabolismo , Animales , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Ratones , Fosfolípido Hidroperóxido Glutatión Peroxidasa/metabolismo , Fosfolípido Hidroperóxido Glutatión Peroxidasa/genética , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Transducción de Señal/efectos de los fármacos , Ácidos Grasos no Esterificados/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Glutamato-Cisteína Ligasa/metabolismo , Glutamato-Cisteína Ligasa/genética , Línea Celular , Especies Reactivas de Oxígeno/metabolismo , Estrés Oxidativo/efectos de los fármacosRESUMEN
Aminopeptidase N (APN/CD13) is a widely expressed transmembrane ectoenzyme that is crucial for maintaining normal physiological activities. It exhibits abnormal activity closely associated with hepatic fibrosis and nonalcoholic fatty liver disease (NAFLD). Therefore, there is a high demand for noninvasive detection of aminopeptidase N (APN) in the diagnosis and research of related diseases. Here, we developed a small molecule fluorescent probe, Hcy-APN, which is a fluorescent probe with high sensitivity and selectivity for the detection of APN. Furthermore, we synthesized the fluorescent nanoprobe Hcy-APN@MSN by self-assembling Hcy-APN and mesoporous silica nanoparticles in solution using a combination of molecular probe design and nanofunctionalization strategies. The detection limit of this probe was 1.5 ng/mL. Hcy-APN@MSN exhibits more stable spectral characteristics compared to Hcy-APN and is suitable for detecting APN activity in live cells and mice. Hcy-APN@MSN was utilized for in vivo and intracellular imaging of NAFLD and hepatic fibrosis at different stages, as well as for a systematic assessment of APN levels in the liver. The results confirm an elevation in the expression levels of APN in NAFLD and hepatic fibrosis models. Furthermore, we investigated the inhibitory effect of the APN inhibitor bestatin in nonalcoholic fatty liver and hepatic fibrosis disease models, confirming its regulatory effect on APN levels in cells and in vivo in both disease models. Therefore, this study may offer diagnostic possibilities for detecting NAFLD and hepatic fibrosis.
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Antígenos CD13 , Colorantes Fluorescentes , Cirrosis Hepática , Enfermedad del Hígado Graso no Alcohólico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/diagnóstico , Antígenos CD13/metabolismo , Antígenos CD13/antagonistas & inhibidores , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Animales , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Ratones , Humanos , Nanopartículas/química , Ratones Endogámicos C57BL , Imagen Óptica , Masculino , Dióxido de Silicio/químicaRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Sea buckthorn (Hippophae rhamnoides L.) is a traditional Chinese medicinal and possesses a rich medical history in terms of treating gastric disorders, sputum and cough and liver injuries in oriental medicinal system. By reason of the complicated chemical constituents, the material basis and potential pharmacological mechanism of sea buckthorn acting on Non-alcoholic fatty liver disease (NAFLD) has not been clearly elucidated. AIM OF THE STUDY: To explore the pharmacological efficacy and underlying mechanism of sea buckthorn triterpenoid acid enrichment (STE) in the treatment of NAFLD. MATERIALS AND METHODS: The approaches of Network pharmacology and experiment validation in vitro and in vivo were applied in this study. Firstly, targets of triterpenoid acid compounds and NAFLD were collected from databases. The crucial targets were screened by the construction of protein-protein interaction (PPI) network. Furthermore, the potential signaling pathways and targets affected by STE was predicted by GO together with KEGG enrichment analysis. Finally, the experiment validation was carried out through high-fat feeding NAFLD mice and lipid accumulation HepG2 cell model. Lipids and liver related biochemical indicators were determined, Oil Red O and H&E staining were employed to observe fat accumulation. In addition, the expression levels of proteins of key target and signal pathway anticipated in network pharmacology were detected to elaborated its action mechanism. RESULTS: A total of 180 intersecting potential targets for enhancing NAFLD with STE were eventually identified. 6 key targets including AKT1, TNF, IL6, INS, JUN, STAT3 and TP53 were further identified and the AMPK-SREBP1 pathway was enriched. Animal experiment result showed that STE treatment could significantly reduce the levels of TG, TC, LDL-C, ALT and AST, increase the levels of HDL-C in serum, and improve lipid accumulation of epididymal fat and liver. The results of the lipid accumulation cell model indicated that STE and key compound oleanolic acid could diminish intracellular lipid levels of TG, TC, LDL-C and number of lipid droplets. Western blot results showed that the above beneficial effects could be achieved by regulating the expression of p-AMPK/AMPK, SREBP1, FAS, ACC, SCD protein. CONCLUSION: This study confirmed the effect of STE on improving NAFLD and the potential action mechanism was involved in the regulation of the AMPK-SREBP1 pathway.