RESUMEN
Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease and represents the main cause of liver cirrhosis and hepatocellular carcinoma. Cav3.2 is a T-type calcium channel that is widely present in tissues throughout the body and plays a vital role in energy and metabolic balance. However, the effects of Cav3.2 on the NFALD remain unclear. Here, we investigated the role of Cav3.2 channel in the development and progression of NAFLD. After 16 weeks on a high-fat diets (HFD), Cav3.2 knockout (Cav3.2 KO) improved hepatic steatosis, liver injury and metabolic syndrome in an NAFLD mouse model. We provided evidence that Cav3.2 KO inhibited HFD-induced hepatic oxidative stress, inflammation and hepatocyte apoptosis. In addition, Cav3.2 KO also attenuated hepatic lipid accumulation, oxidative stress, inflammation and hepatocyte apoptosis in palmitic acid/oleic acid (PAOA)-treated primary hepatocytes. These results suggest that therapeutic approaches targeting Cav3.2 provide effective approaches for treating NAFLD.
Asunto(s)
Apoptosis , Canales de Calcio Tipo T , Dieta Alta en Grasa , Hepatocitos , Ratones Noqueados , Enfermedad del Hígado Graso no Alcohólico , Estrés Oxidativo , Animales , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Canales de Calcio Tipo T/genética , Canales de Calcio Tipo T/metabolismo , Ratones , Dieta Alta en Grasa/efectos adversos , Hepatocitos/metabolismo , Hepatocitos/patología , Masculino , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Inflamación/genética , Inflamación/metabolismoRESUMEN
Genetic susceptibility to metabolic associated fatty liver disease (MAFLD) is complex and poorly characterized. Accurate characterization of the genetic background of hepatic fat content would provide insights into disease etiology and causality of risk factors. We performed genome-wide association study (GWAS) on two noninvasive definitions of hepatic fat content: magnetic resonance imaging proton density fat fraction (MRI-PDFF) in 16,050 participants and fatty liver index (FLI) in 388,701 participants from the United Kingdom (UK) Biobank (UKBB). Heritability, genetic overlap, and similarity between hepatic fat content phenotypes were analyzed, and replicated in 10,398 participants from the University Medical Center Groningen (UMCG) Genetics Lifelines Initiative (UGLI). Meta-analysis of GWASs of MRI-PDFF in UKBB revealed five statistically significant loci, including two novel genomic loci harboring CREB3L1 (rs72910057-T, P = 5.40E-09) and GCM1 (rs1491489378-T, P = 3.16E-09), respectively, as well as three previously reported loci: PNPLA3, TM6SF2, and APOE. GWAS of FLI in UKBB identified 196 genome-wide significant loci, of which 49 were replicated in UGLI, with top signals in ZPR1 (P = 3.35E-13) and FTO (P = 2.11E-09). Statistically significant genetic correlation (rg) between MRI-PDFF (UKBB) and FLI (UGLI) GWAS results was found (rg = 0.5276, P = 1.45E-03). Novel MRI-PDFF genetic signals (CREB3L1 and GCM1) were replicated in the FLI GWAS. We identified two novel genes for MRI-PDFF and 49 replicable loci for FLI. Despite a difference in hepatic fat content assessment between MRI-PDFF and FLI, a substantial similar genetic architecture was found. FLI is identified as an easy and reliable approach to study hepatic fat content at the population level.
Asunto(s)
Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Hígado , Humanos , Femenino , Masculino , Factores de Riesgo , Predisposición Genética a la Enfermedad/genética , Hígado/diagnóstico por imagen , Hígado/metabolismo , Hígado/patología , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética , Imagen por Resonancia Magnética , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Adulto , Anciano , Hígado Graso/genética , Hígado Graso/diagnóstico por imagenRESUMEN
Ferroptosis plays a crucial role in the development of non-alcoholic fatty liver disease (NAFLD). In this study, we aimed to use a comprehensive bioinformatics approach and experimental validation to identify and verify potential ferroptosis-related genes in NAFLD. We downloaded the microarray datasets for screening differentially expressed genes (DEGs) and identified the intersection of these datasets with ferroptosis-related DEGs from the Ferroptosis database. Subsequently, ferroptosis-related DEGs were obtained using SVM analysis; the LASSO algorithm was then used to identify six marker genes. Furthermore, the CIBERSORT algorithm was used to estimate the proportion of different types of immune cells. Subsequently, we constructed drug regulatory networks and ceRNA regulatory networks. We identified six genes as marker genes for NAFLD, demonstrating their robust diagnostic abilities. Subsequent functional enrichment analysis results revealed that these marker genes were associated with multiple diseases and play a key role in NAFLD via the regulation of immune response and amino acid metabolism, among other pathways. The expression of hepatic EGR1, IL-6, SOCS1, and NR4A1 was significantly downregulated in the NAFLD model. Our findings provide new insights and molecular clues for understanding and treating NAFLD. Further studies are needed to assess the diagnostic potential of these markers for NAFLD.
Asunto(s)
Biomarcadores , Biología Computacional , Ferroptosis , Enfermedad del Hígado Graso no Alcohólico , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Ferroptosis/genética , Biomarcadores/metabolismo , Humanos , Animales , Ratones , Perfilación de la Expresión Génica , Redes Reguladoras de GenesRESUMEN
Nonalcoholic fatty liver disease (NAFLD) is a serious threat to public health, but its underlying mechanism remains poorly understood. In screening important genes using Gene Importance Calculator (GIC) we developed previously, ribosomal modification protein rimK-like family member A (RIMKLA) was predicted as one essential gene but its functions remained largely unknown. The current study determined the roles of RIMKLA in regulating glucose and lipid metabolism. RIMKLA expression was reduced in livers of human and mouse with NAFLD. Hepatic RIMKLA overexpression ameliorated steatosis and hyperglycemia in obese mice. Hepatocyte-specific RIMKLA knockout aggravated high-fat diet (HFD)-induced dysregulated glucose/lipid metabolism in mice. Mechanistically, RIMKLA is a new protein kinase that phosphorylates betaine-homocysteine S-methyltransferase 1 (BHMT1) at threonine 45 (Thr45) site. Upon phosphorylation at Thr45 and activation, BHMT1 eliminated homocysteine (Hcy) to inhibit the activity of transcription factor activator protein 1 (AP1) and its induction on fatty acid synthase (FASn) and cluster of differentiation 36 (CD36) gene transcriptions, concurrently repressing lipid synthesis and uptake in hepatocytes. Thr45 to alanine (T45A) mutation inactivated BHMT1 to abolish RIMKLA's repression on Hcy level, AP1 activity, FASn/CD36 expressions, and lipid deposition. BHMT1 overexpression rescued the dysregulated lipid metabolism in RIMKLA-deficient hepatocytes. In summary, RIMKLA is a novel protein kinase that phosphorylates BHMT1 at Thr45 to repress lipid synthesis and uptake. Under obese condition, inhibition of RIMKLA impairs BHMT1 activity to promote hepatic lipid deposition.
Asunto(s)
Betaína-Homocisteína S-Metiltransferasa , Metabolismo de los Lípidos , Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Humanos , Betaína-Homocisteína S-Metiltransferasa/genética , Betaína-Homocisteína S-Metiltransferasa/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Metabolismo de los Lípidos/genética , Dieta Alta en Grasa/efectos adversos , Hepatocitos/metabolismo , Masculino , Ratones Noqueados , Fosforilación/genéticaRESUMEN
BACKGROUND: As the leading cause of end-stage liver disease, nonalcoholic fatty liver disease (NAFLD) is mainly induced by lipid dyshomeostasis. The translation of endogenous circular RNAs (circRNAs) is closely related to the progression of various diseases, but the involvement of circRNAs in NAFLD has not been determined. METHODS: Combined high-throughput circRNA profiles were used to identify circRNAs with translational potential. The underlying molecular mechanisms were investigated by RNA sequencing, pull-down/MS and site-specific mutagenesis. RESULTS: In this study, we focused on circ-SLC9A6, an abnormally highly expressed circRNA in human and mouse liver tissue during NAFLD development that exacerbates metabolic dyshomeostasis in hepatocytes by encoding a novel peptide called SLC9A6-126aa in vivo and in vitro. YTHDF2-mediated degradation of m6A-modified circ-SLC9A6 was found to be essential for the regulation of SLC9A6-126aa expression. We further found that the phosphorylation of SLC9A6-126aa by AKT was crucial for its cytoplasmic localization and the maintenance of physiological homeostasis, whereas high-fat stress induced substantial translocation of unphosphorylated SLC9A6-126aa to the nucleus, resulting in a vicious cycle of lipid metabolic dysfunction. Nuclear SLC9A6-126aa promotes transcriptional activation of the target gene CD36 and enhances its occupancy of the CD36 promoter locus by regulating MOF-mediated histone H4K16 acetylation. Hepatic CD36 depletion significantly ameliorated hyperactivated MAPK signalling and lipid disturbance in SLC9A6-126aa transgenic mice. Clinically, increasing levels of SLC9A6-126aa were observed during NAFLD progression and were found to be positively correlated with the CD36 and MAPK cascades. CONCLUSION: This study revealed the role of circ-SLC9A6-derived SLC9A6-126aa in the epigenetic modification-mediated regulation of lipid metabolism. Our findings may provide promising therapeutic targets for NAFLD and new insights into the pathological mechanisms of metabolic diseases. HIGHLIGHTS: Under normal circumstances, driven by m6A modification, YTHDF2 directly recognizes and degrades circ-SLC9A6, thereby inhibiting the translation of SLC9A6-126aa. Additionally, AKT1 phosphorylates and inhibits the nuclear translocation of SLC9A6-126aa. In NAFLD, lipid overload leads to YTHDF2 and AKT1 deficiency, ultimately increasing the expression and nuclear import of SLC9A6-126aa. Nuclear SLC9A6-126aa binds directly to the CD36 promoter and initiates CD36 transcription, which induces lipid dyshomeostasis.
Asunto(s)
Antígenos CD36 , Enfermedad del Hígado Graso no Alcohólico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ratones , Animales , Antígenos CD36/genética , Antígenos CD36/metabolismo , Humanos , ARN Circular/genética , ARN Circular/metabolismo , Metabolismo de los Lípidos/genética , Péptidos/metabolismo , Péptidos/genética , Homeostasis/genética , Masculino , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: Type 2 diabetes (T2D) and non-alcoholic fatty liver disease (NAFLD) are prevalent metabolic disorders with overlapping pathophysiological mechanisms. A comprehensive understanding of the shared molecular pathways involved in these conditions can advance the development of effective therapeutic interventions. METHODS: We used two datasets sourced from the Gene Expression Omnibus (GEO) database to identify common differentially expressed genes (DEGs) between T2D and NAFLD. Subsequently, we conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses to identify the enriched biological processes and signaling pathways. In addition, we performed a protein-protein interaction (PPI) network analysis to identify hub genes with pivotal roles. To validate our findings, we established a type 2 diabetic mouse model with NAFLD. RESULTS: Our analysis identified 53 DEGs shared between T2D and NAFLD. Enrichment analysis revealed their involvement in signal transduction, transcriptional regulation, and cell proliferation as well as in the ferroptosis signaling pathways. PPI network analysis identified ten hub genes, namely CD44, CASP3, FYN, KLF4, HNRNPM, HNRNPU, FUBP1, RUNX1, NOTCH3, and ANXA2. We validated the differential expression of FYN, HNRNPU, and FUBP1 in liver tissues of a type 2 diabetic mouse model with NAFLD. CONCLUSIONS: Our study offers valuable insights into the shared molecular mechanisms underlying T2D and NAFLD. The identified hub genes and pathways present promising prospects as therapeutic targets to address these prevalent metabolic disorders.
Asunto(s)
Biología Computacional , Diabetes Mellitus Tipo 2 , Modelos Animales de Enfermedad , Enfermedad del Hígado Graso no Alcohólico , Mapas de Interacción de Proteínas , Animales , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Ratones , Biología Computacional/métodos , Factor 4 Similar a Kruppel , Masculino , Ratones Endogámicos C57BL , Redes Reguladoras de Genes , Transducción de Señal , Perfilación de la Expresión Génica , HumanosRESUMEN
OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) has significant genetic susceptibility. Adipocytokines play a crucial role in NAFLD development by participating in insulin resistance and hepatic steatosis. However, the association between adipocytokine pathway genes and NAFLD remains unclear. This study aims to explore the association of gene polymorphisms in the adipocytokine pathway and their interactions with NAFLD in obese children. METHODS: A case-control study was conducted, dividing obese children into NAFLD and control groups. Peripheral venous blood (2 mL) was collected from each participant for DNA extraction. A total of 14 single nucleotide polymorphisms (SNP) in the adipocytokine pathway were genotyped using multiplex PCR and high-throughput sequencing. Univariate and multivariate Logistic regression analyses were used to assess the association between SNP and NAFLD in obese children. Dominant models were used to analyze additive and multiplicative interactions via crossover analysis and Logistic regression. Generalized multifactor dimensionality reduction (GMDR) was used to detect gene-gene interactions among the 14 SNPs and their association with NAFLD in obese children. RESULTS: A total of 1 022 children were included, with 511 in the NAFLD group and 511 in the control group. After adjusting for age, gender, and BMI, multivariate Logistic regression showed that PPARG rs1801282 was associated with NAFLD in the obese children in 3 genetic models: heterozygote model (CG vs CC, OR=0.58, 95% CI 0.36 to 0.95, P=0.029), dominant model (GG+CG vs CC, OR=0.62, 95% CI 0.38 to 1.00, P=0.049), and overdominant model (CC+GG vs CG, OR=1.72, 95% CI 1.06 to 2.80, P=0.028). PRKAG2 rs12703159 was associated with NAFLD in 4 genetic models: heterozygous model (CT vs CC, OR=1.51, 95% CI 1.10 to 2.07, P=0.011), dominant model (CT+TT vs CC, OR=1.50, 95% CI 1.10 to 2.03, P=0.010), overdominant model (CC+TT vs CT, OR=0.67, 95% CI 0.49 to 0.92, P=0.012), and additive model (CC vs CT vs TT, OR=1.40, 95% CI 1.07 to 1.83, P=0.015). No significant multiplicative or additive interaction between PPARG rs1801282 and PRKAG2 rs12703159 was found in association with NAFLD. GMDR analysis, adjusted for age, gender, and BMI, revealed no statistically significant interactions among the 14 SNPs (all P>0.05). CONCLUSIONS: Mutations in PPARG rs1801282 and PRKAG2 rs12703159 are associated with NAFLD in obese children. However, no gene-gene interactions among the SNP are found to be associated with NAFLD in obese children.
Asunto(s)
Adipoquinas , Predisposición Genética a la Enfermedad , Enfermedad del Hígado Graso no Alcohólico , Polimorfismo de Nucleótido Simple , Humanos , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Niño , Estudios de Casos y Controles , Masculino , Femenino , Adipoquinas/genética , Adipoquinas/sangre , Obesidad/genética , Obesidad/complicaciones , PPAR gamma/genética , Adolescente , Obesidad Infantil/genética , Obesidad Infantil/complicacionesRESUMEN
Obesity, cardiovascular diseases (CVD), and nonalcoholic fatty liver disease (NAFLD) pose significant worldwide health challenges, characterized by complex interplay among inflammatory pathways that underlie their development. In this review, we examine the contribution of inflammation and associated signaling molecules to the pathogenesis of these conditions, while also emphasizing the significant participation of non-coding RNAs (ncRNAs) in modulating inflammatory pathways. In the context of obesity, aberrant expression patterns of inflammatory-associated miRNAs play a contributory role in adipose tissue inflammation and insulin resistance, thereby exacerbating disturbances in metabolic homeostasis. Similarly, in CVD, dysregulated miRNA expression alters inflammatory reactions, disrupts endothelial function, and induces cardiac remodeling, thereby impacting the advancement of the disease. Moreover, in the context of NAFLD, inflammatory-associated miRNAs are implicated in mediating hepatic inflammation, lipid deposition, and fibrosis, underscoring their candidacy as promising therapeutic targets. Additionally, the competing endogenous RNA (ceRNA) network has emerged as a novel regulatory mechanism in the etiology of CVD, obesity, and NAFLD, wherein ncRNAs assume pivotal roles in facilitating communication across diverse molecular pathways. Moreover, in the concluding section, we underscored the potential efficacy of directing interventions towards inflammatory-related miRNAs utilizing herbal remedies and therapies based on exosome delivery systems as a promising strategy for ameliorating pathologies associated with inflammation in obesity, CVD, and NAFLD.
Asunto(s)
Enfermedades Cardiovasculares , Inflamación , MicroARNs , Enfermedad del Hígado Graso no Alcohólico , Obesidad , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Inflamación/genética , Inflamación/metabolismo , Obesidad/genética , Obesidad/metabolismo , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/metabolismo , AnimalesRESUMEN
Prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD), formerly known as non-alcoholic fatty liver disease, increases worldwide and associates with type 2 diabetes and other cardiometabolic diseases. Here we demonstrate that Sema3a is elevated in liver sinusoidal endothelial cells of animal models for obesity, type 2 diabetes and MASLD. In primary human liver sinusoidal endothelial cells, saturated fatty acids induce expression of SEMA3A, and loss of a single allele is sufficient to reduce hepatic fat content in diet-induced obese mice. We show that semaphorin-3A regulates the number of fenestrae through a signaling cascade that involves neuropilin-1 and phosphorylation of cofilin-1 by LIM domain kinase 1. Finally, inducible vascular deletion of Sema3a in adult diet-induced obese mice reduces hepatic fat content and elevates very low-density lipoprotein secretion. Thus, we identified a molecular pathway linking hyperlipidemia to microvascular defenestration and early development of MASLD.
Asunto(s)
Células Endoteliales , Hígado , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico , Semaforina-3A , Transducción de Señal , Animales , Humanos , Células Endoteliales/metabolismo , Células Endoteliales/patología , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/genética , Semaforina-3A/metabolismo , Semaforina-3A/genética , Neuropilina-1/metabolismo , Neuropilina-1/genética , Obesidad/metabolismo , Obesidad/patología , Obesidad/genética , Cofilina 1/metabolismo , Cofilina 1/genética , Modelos Animales de Enfermedad , Masculino , Fosforilación , Células Cultivadas , Ratones , Ratones Noqueados , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Diabetes Mellitus Tipo 2/genética , Dieta Alta en Grasa/efectos adversosRESUMEN
Environmental pollutants, including polychlorinated biphenyls (PCBs), act as endocrine disruptors and impair various physiological processes. PCB 126 is associated with steatohepatitis, fibrosis, cirrhosis, and other hepatic injuries. These disorders can be regulated by microRNAs (miRNAs). Therefore, this study aimed to investigate the role of miRNAs in non-alcoholic fatty liver disease associated with exposure to PCB 126. Adult male C57BL/6 mice were exposed to PCB 126 (5 µmol/kg of body weight) for 10 weeks. The PCB group showed lipid accumulation in the liver in the presence of macro- and microvesicular steatosis and fibrosis with increased inflammatory and profibrotic gene expression, consistent with non-alcoholic steatohepatitis (NASH). PCB exposure also upregulated miR-155 and miR-34a, which induce the expression of proinflammatory cytokines and inflammation in the liver and reduce the expression of peroxisome proliferator-activated receptor α, which, in turn, impairs lipid oxidation and hepatic steatosis. Therefore, the present study showed that PCB 126 induced NASH via potential mechanisms involving miR-155 and miR-34a, which may contribute to the development of new diagnostic markers and therapeutic strategies.
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Cirrosis Hepática , Ratones Endogámicos C57BL , MicroARNs , Bifenilos Policlorados , Regulación hacia Arriba , Animales , MicroARNs/genética , MicroARNs/metabolismo , Bifenilos Policlorados/toxicidad , Masculino , Ratones , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Regulación hacia Arriba/efectos de los fármacos , Hígado/metabolismo , Hígado/efectos de los fármacos , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/inducido químicamente , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Contaminantes Ambientales/toxicidad , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/genéticaRESUMEN
The prevalence of Metabolic-associated fatty liver disease (MAFLD) has been steadily increasing worldwide, paralleling the global epidemic of obesity and diabetes. It is estimated that approximately one-quarter of the global population is affected by MAFLD. Despite its high prevalence, MAFLD often goes undiagnosed due to the lack of specific symptoms in its early stages. However, as the disease progresses, it can lead to more severe liver-related complications such as fibrosis, cirrhosis, and hepatocellular carcinoma. Therefore, we aimed to investigate the expression levels of the nucleotide-binding oligomerization domain, leucine-rich repeat (LRR)-containing proteins (NLR) family pyrin domain-containing protein 3 [NLRP3] inflammasome pathway components, NLRP3 and interleukin 1ß (IL-1ß) genes in patients with MAFLD with various degrees of steatosis and fibrosis. Participants were classified into two equal groups; MAFLD group: consisted of 120 patients with different degrees of hepatic fibrosis and steatosis based on fibro scan results. The non-MAFLD group was comprised of 107 participants. Molecular analysis of pyrin domain-containing protein 3 and IL-1ß relative gene expressions was performed in the blood of all participants, using Real-time quantitative polymerase chain reaction (RT-qPCR). Patients with post-MAFLD hepatic fibrosis had significantly higher relative gene expression levels of IL-1ß and NLRP3; with IL-1ß > 1.1 had AUC of 0.919, sensitivity of 88.33, specificity of 96.26, PPV of 96.4, and NPV of 88 and 92.3 accuracy (p value < 0.001). NLRP3 > 1.33 had a sensitivity of 97.5, specificity of 99.07, PPV of 99.2, NPV of 97.2, and 98.3 accuracy with an AUC of 0.991 (p value < 0.001) as predictors of post-MAFLD hepatic fibrosis.. A significant increase in the mean relative gene expression levels of both IL-1ß and NLRP3 found in patients with early fibrosis (F0-F1-2); 31.97 ± 11.8 and 6.76 ± 2.18, respectively; compared with patients with advanced hepatic fibrosis stages (F2-F3); 2.62 ± 3.71 and 4.27 ± 2.99 (p < 0.001 each). The present study provides novel evidence for the possible involvement of IL-1ß and NLRP3 inflammasome in metabolic-associated fatty liver disease pathogenesis and could be valid markers for the early detection of post-MAFLD hepatic fibrosis.
Asunto(s)
Inflamasomas , Interleucina-1beta , Cirrosis Hepática , Proteína con Dominio Pirina 3 de la Familia NLR , Humanos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Masculino , Femenino , Inflamasomas/metabolismo , Persona de Mediana Edad , Interleucina-1beta/metabolismo , Interleucina-1beta/genética , Adulto , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Transducción de SeñalRESUMEN
BACKGROUND: Nonalcoholic Steatohepatitis (NASH) results from complex liver conditions involving metabolic, inflammatory, and fibrogenic processes. Despite its burden, there has been a lack of any approved food-and-drug administration therapy up till now. PURPOSE: Utilizing machine learning (ML) algorithms, the study aims to identify reliable potential genes to accurately predict the treatment response in the NASH animal model using biochemical and molecular markers retrieved using bioinformatics techniques. METHODS: The NASH-induced rat models were administered various microbiome-targeted therapies and herbal drugs for 12 weeks, these drugs resulted in reducing hepatic lipid accumulation, liver inflammation, and histopathological changes. The ML model was trained and tested based on the Histopathological NASH score (HPS); while (0-4) HPS considered Improved NASH and (5-8) considered non-improved, confirmed through rats' liver histopathological examination, incorporates 34 features comprising 20 molecular markers (mRNAs-microRNAs-Long non-coding-RNAs) and 14 biochemical markers that are highly enriched in NASH pathogenesis. Six different ML models were used in the proposed model for the prediction of NASH improvement, with Gradient Boosting demonstrating the highest accuracy of 98% in predicting NASH drug response. FINDINGS: Following a gradual reduction in features, the outcomes demonstrated superior performance when employing the Random Forest classifier, yielding an accuracy of 98.4%. The principal selected molecular features included YAP1, LATS1, NF2, SRD5A3-AS1, FOXA2, TEAD2, miR-650, MMP14, ITGB1, and miR-6881-5P, while the biochemical markers comprised triglycerides (TG), ALT, ALP, total bilirubin (T. Bilirubin), alpha-fetoprotein (AFP), and low-density lipoprotein cholesterol (LDL-C). CONCLUSION: This study introduced an ML model incorporating 16 noninvasive features, including molecular and biochemical signatures, which achieved high performance and accuracy in detecting NASH improvement. This model could potentially be used as diagnostic tools and to identify target therapies.
Asunto(s)
Modelos Animales de Enfermedad , Aprendizaje Automático , Enfermedad del Hígado Graso no Alcohólico , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Ratas , Hígado/patología , Hígado/metabolismo , Hígado/efectos de los fármacos , Masculino , Proteínas Señalizadoras YAP/genética , Biomarcadores/sangre , MicroARNs/genéticaRESUMEN
BACKGROUND: Fibrosis-4 (FIB4) is a recommended noninvasive test to assess hepatic fibrosis among patients with metabolic dysfunction-associated steatotic liver disease (MASLD). Here, we used FIB4 trajectory over time (ie, "slope" of FIB4) as a surrogate marker of liver fibrosis progression and examined if FIB4 slope is associated with clinical and genetic factors among individuals with clinically defined MASLD within the Million Veteran Program Cohort. METHODS: In this retrospective cohort study, FIB4 slopes were estimated through linear regression for participants with clinically defined MASLD and FIB4 <2.67 at baseline. FIB4 slope was correlated with demographic parameters and clinical outcomes using logistic regression and Cox proportional hazard models. FIB4 slope as a quantitative phenotype was used in a genome-wide association analysis in ancestry-specific analysis and multiancestry meta-analysis using METAL. RESULTS: FIB4 slopes, generated from 98,361 subjects with MASLD (16,045 African, 74,320 European, and 7996 Hispanic), showed significant associations with sex, ancestry, and cardiometabolic risk factors (p < 0.05). FIB4 slopes also correlated strongly with hepatic outcomes and were independently associated with time to cirrhosis. Five genetic loci showed genome-wide significant associations (p < 5 × 10-8) with FIB4 slope among European ancestry subjects, including 2 known (PNPLA3 and TM6SF2) and 3 novel loci (TERT 5.1 × 10-11; LINC01088, 3.9 × 10-8; and MRC1, 2.9 × 10-9). CONCLUSIONS: Linear trajectories of FIB4 correlated significantly with time to progression to cirrhosis, with liver-related outcomes among individuals with MASLD and with known and novel genetic loci. FIB4 slope may be useful as a surrogate measure of fibrosis progression.
Asunto(s)
Progresión de la Enfermedad , Estudio de Asociación del Genoma Completo , Cirrosis Hepática , Humanos , Masculino , Femenino , Cirrosis Hepática/genética , Cirrosis Hepática/complicaciones , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Anciano , Proteínas de la Membrana/genética , Hígado Graso/genética , Biomarcadores , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Aciltransferasas , Fosfolipasas A2 Calcio-IndependienteRESUMEN
BACKGROUND: Abdominal obesity increases the risk for non-alcoholic fatty liver disease (NAFLD), now known as metabolic dysfunction-associated steatotic liver disease (MASLD). METHODS: To elucidate the directional cell-type level biological mechanisms underlying the association between abdominal obesity and MASLD, we integrated adipose and liver single nucleus RNA-sequencing and bulk cis-expression quantitative trait locus (eQTL) data with the UK Biobank genome-wide association study (GWAS) data using colocalization. Then we used colocalized cis-eQTL variants as instrumental variables in Mendelian randomization (MR) analyses, followed by functional validation experiments on the target genes of the cis-eQTL variants. FINDINGS: We identified 17 colocalized abdominal obesity GWAS variants, regulating 17 adipose cell-type marker genes. Incorporating these 17 variants into MR discovers a putative tissue-of-origin, cell-type-aware causal effect of abdominal obesity on MASLD consistently with multiple MR methods without significant evidence for pleiotropy or heterogeneity. Single cell data confirm the adipocyte-enriched mean expression of the 17 genes. Our cellular experiments across human adipogenesis identify risk variant -specific epigenetic and transcriptional mechanisms. Knocking down two of the 17 genes, PPP2R5A and SH3PXD2B, shows a marked decrease in adipocyte lipidation and significantly alters adipocyte function and adipogenesis regulator genes, including DGAT2, LPL, ADIPOQ, PPARG, and SREBF1. Furthermore, the 17 genes capture a characteristic MASLD expression signature in subcutaneous adipose tissue. INTERPRETATION: Overall, we discover a significant cell-type level effect of abdominal obesity on MASLD and trace its biological effect to adipogenesis. FUNDING: NIH grants R01HG010505, R01DK132775, and R01HL170604; the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (Grant No. 802825), Academy of Finland (Grants Nos. 333021), the Finnish Foundation for Cardiovascular Research the Sigrid Jusélius Foundation and the Jane and Aatos Erkko Foundation; American Association for the Study of Liver Diseases (AASLD) Advanced Transplant Hepatology award and NIH/NIDDK (P30DK41301) Pilot and Feasibility award; NIH/NIEHS F32 award (F32ES034668); Finnish Diabetes Research Foundation, Kuopio University Hospital Project grant (EVO/VTR grants 2005-2021), the Academy of Finland grant (Contract no. 138006); Academy of Finland (Grant Nos 335443, 314383, 272376 and 266286), Sigrid Jusélius Foundation, Finnish Medical Foundation, Finnish Diabetes Research Foundation, Novo Nordisk Foundation (#NNF20OC0060547, NNF17OC0027232, NNF10OC1013354) and Government Research Funds to Helsinki University Hospital; Orion Research Foundation, Maud Kuistila Foundation, Finish Medical Foundation, and University of Helsinki.
Asunto(s)
Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Obesidad Abdominal , Sitios de Carácter Cuantitativo , Humanos , Obesidad Abdominal/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ARN , Proteína Fosfatasa 2/genética , Proteína Fosfatasa 2/metabolismo , Núcleo Celular/metabolismo , Núcleo Celular/genética , Adipogénesis/genética , Análisis de la Célula Individual , Regulación de la Expresión GénicaRESUMEN
OBJECTIVE: Currently, little is known about the mechanism(s) regulating global and specific protein translation during metabolic dysfunction-associated steatohepatitis (MASH; previously known as non-alcoholic steatohepatitis, NASH). METHODS: Unbiased label-free quantitative proteome, puromycin-labelling and polysome profiling were used to understand protein translation activity in vitro and in vivo. RESULTS: We observed a global decrease in protein translation during lipotoxicity in human primary hepatocytes, mouse hepatic AML12 cells, and livers from a dietary mouse model of MASH. Interestingly, proteomic analysis showed that Rplp1, which regulates ribosome and translation pathways, was one of the most downregulated proteins. Moreover, decreased Esrra expression and binding to the Rplp1 promoter, diminished Rplp1 gene expression during lipotoxicity. This, in turn, reduced global protein translation and Esrra/Rplp1-dependent translation of lysosome (Lamp2, Ctsd) and autophagy (sqstm1, Map1lc3b) proteins. Of note, Esrra did not increase its binding to these gene promoters or their gene transcription, confirming its regulation of their translation during lipotoxicity. Notably, hepatic Esrra-Rplp1-dependent translation of lysosomal and autophagy proteins also was impaired in MASH patients and liver-specific Esrra knockout mice. Remarkably, alternate day fasting induced Esrra-Rplp1-dependent expression of lysosomal proteins, restored autophagy, and reduced lipotoxicity, inflammation, and fibrosis in hepatic cell culture and in vivo models of MASH. CONCLUSIONS: Esrra regulation of Rplp1-mediated translation of lysosome/autolysosome proteins was downregulated during MASH. Alternate day fasting activated this novel pathway and improved MASH, suggesting that Esrra and Rplp1 may serve as therapeutic targets for MASH. Our findings also provided the first example of a nuclear hormone receptor, Esrra, to not only regulate transcription but also protein translation, via induction of Rplp1.
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Ayuno , Lisosomas , Enfermedad del Hígado Graso no Alcohólico , Animales , Ratones , Humanos , Lisosomas/metabolismo , Ayuno/metabolismo , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Ratones Endogámicos C57BL , Proteínas Ribosómicas/metabolismo , Proteínas Ribosómicas/genética , Masculino , Hepatocitos/metabolismo , Biosíntesis de Proteínas , Autofagia , Hígado/metabolismo , Ratones NoqueadosRESUMEN
Non-alcoholic fatty liver disease (NAFLD) is a chronic hepatic disease. The incidence and prevalence of NAFLD have increased greatly in recent years, and there is still a lack of effective drugs. Autophagy plays an important role in promoting liver metabolism and maintaining liver homeostasis, and defects in autophagy levels are considered to be related to the development of NAFLD. However, the molecular mechanisms of autophagy in NAFLD still remain unknown. In this study, we identified 6 autophagy-associated hub genes using gene expression profiles obtained from the GSE48452 and GSE89632 datasets. Biomarkers were screened according to gene significance (GS) and module membership (MM) using weighted gene co-expression network analysis (WGCNA), and the immune infiltration landscape of the liver in NAFLD patients was explored using the CIBERSORT algorithm. Subsequently, we analyzed the relationship between liver non-parenchymal cells and autophagy-related hub genes using scRNA-seq data (GSE129516). Finally, we separated the NAFLD patients into two groups based on 6 hub genes by consensus clustering and screened 10 potential autophagy-related small molecules based on the cMAP database.
Asunto(s)
Autofagia , Redes Reguladoras de Genes , Hígado , Enfermedad del Hígado Graso no Alcohólico , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Humanos , Autofagia/genética , Hígado/metabolismo , Hígado/patología , Perfilación de la Expresión Génica , Transcriptoma/genética , Biomarcadores , Biología Computacional/métodos , Bases de Datos GenéticasRESUMEN
BACKGROUND: This study examines genetic variations in CYP2E1 (rs6413432, rs3813867), GCKR (rs780094, rs1260326), and PNPLA3 (rs738409) among Turkish patients to assess their influence on nonalcoholic steatohepatitis. METHODS: Allele and genotype frequencies were compared between 245 NASH patients and 120 healthy controls using SNP genotyping via polymerase chain reaction-restriction fragment length polymorphism. Additionally, the deviation of the observed genotype frequencies from Hardy-Weinberg proportion was examined. RESULTS: No significant differences were found in the allelic and genotypic distributions of rs6413432, rs3813867, and rs780094 between NASH patients and healthy controls. However, significant disparities were noted for rs1260326 and rs738409. Gender and age-specific distributions showed no notable differences. The only observed deviation from Hardy-Weinberg proportion was in the genotype frequency of rs738409. CONCLUSIONS: Variants in GCKR (rs1260326) and PNPLA3 (rs738409) are significantly associated with increased NASH risk in the Turkish population, with the rs738409 variant potentially playing a more prominent role in NASH development.
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Proteínas Adaptadoras Transductoras de Señales , Citocromo P-450 CYP2E1 , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Lipasa , Proteínas de la Membrana , Enfermedad del Hígado Graso no Alcohólico , Polimorfismo de Nucleótido Simple , Humanos , Masculino , Femenino , Turquía , Lipasa/genética , Polimorfismo de Nucleótido Simple/genética , Enfermedad del Hígado Graso no Alcohólico/genética , Persona de Mediana Edad , Adulto , Proteínas de la Membrana/genética , Frecuencia de los Genes/genética , Citocromo P-450 CYP2E1/genética , Proteínas Adaptadoras Transductoras de Señales/genética , Alelos , Estudios de Casos y Controles , Anciano , Aciltransferasas , Fosfolipasas A2 Calcio-IndependienteRESUMEN
BACKGROUND: The advent of liquid biopsies presents a novel, minimally invasive methodology for the detection of disease biomarkers, offering a significant advantage over traditional biopsy techniques. Particularly, the analysis of cell-free RNA (cfRNA) has garnered interest due to its dynamic expression profiles and the capability to study various RNA species, including messenger RNA (mRNA) and long non-coding RNA (lncRNA). These attributes position cfRNA as a versatile biomarker with broad potential applications in clinical research and diagnostics. SCOPE OF REVIEW: This review delves into the utility of cfRNA biomarkers as prognostic tools for obesity-related comorbidities, such as diabetes, dyslipidemia, and non-alcoholic fatty liver disease. MAJOR CONCLUSIONS: We evaluate the efficacy of cfRNA in forecasting metabolic outcomes associated with obesity and in identifying patients likely to experience favorable clinical outcomes following bariatric surgery. Additionally, this review synthesizes evidence from studies examining circulating cfRNA across different physiological and pathological states, with a focus on its role in diabetes, including disease progression monitoring and treatment efficacy assessment. Through this exploration, we underscore the emerging relevance of cfRNA signatures in the context of obesity and its comorbidities, setting the stage for future investigative efforts in this rapidly advancing domain.
Asunto(s)
Cirugía Bariátrica , Biomarcadores , Ácidos Nucleicos Libres de Células , Enfermedades Metabólicas , Obesidad , Humanos , Cirugía Bariátrica/métodos , Ácidos Nucleicos Libres de Células/genética , Enfermedades Metabólicas/genética , Enfermedades Metabólicas/metabolismo , Obesidad/cirugía , Obesidad/genética , Obesidad/metabolismo , Pronóstico , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/cirugía , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismoRESUMEN
The pathogenesis of non-alcoholic fatty liver disease (NAFLD) is influenced by a number of variables, including endoplasmic reticulum stress (ER). Thioredoxin domain-containing 5 (TXNDC5) is a member of the protein disulfide isomerase family and acts as an endoplasmic reticulum (ER) chaperone. Nevertheless, the function of TXNDC5 in hepatocytes under ER stress remains largely uncharacterized. In order to identify the role of TXNDC5 in hepatic wild-type (WT) and TXNDC5-deficient (KO) AML12 cell lines, tunicamycin, palmitic acid, and thapsigargin were employed as stressors. Cell viability, mRNA, protein levels, and mRNA splicing were then assayed. The protein expression results of prominent ER stress markers indicated that the ERN1 and EIF2AK3 proteins were downregulated, while the HSPA5 protein was upregulated. Furthermore, the ATF6 protein demonstrated no significant alterations in the absence of TXNDC5 at the protein level. The knockout of TXNDC5 has been demonstrated to increase cellular ROS production and its activity is required to maintain normal mitochondrial function during tunicamycin-induced ER stress. Tunicamycin has been observed to disrupt the protein levels of HSPA5, ERN1, and EIF2AK3 in TXNDC5-deficient cells. However, palmitic acid has been observed to disrupt the protein levels of ATF6, HSPA5, and EIF2AK3. In conclusion, TXNDC5 can selectively activate distinct ER stress pathways via HSPA5, contingent on the origin of ER stress. Conversely, the absence of TXNDC5 can disrupt the EIF2AK3 cascade.
Asunto(s)
Chaperón BiP del Retículo Endoplásmico , Estrés del Retículo Endoplásmico , Retículo Endoplásmico , Hepatocitos , Proteína Disulfuro Isomerasas , Transducción de Señal , Tunicamicina , Chaperón BiP del Retículo Endoplásmico/metabolismo , Proteína Disulfuro Isomerasas/metabolismo , Proteína Disulfuro Isomerasas/genética , Hepatocitos/metabolismo , Animales , Tunicamicina/farmacología , Retículo Endoplásmico/metabolismo , Ratones , Especies Reactivas de Oxígeno/metabolismo , Factor de Transcripción Activador 6/metabolismo , Factor de Transcripción Activador 6/genética , Línea Celular , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas de Choque Térmico/metabolismo , Proteínas de Choque Térmico/genética , Endorribonucleasas/metabolismo , Endorribonucleasas/genética , Ácido Palmítico/farmacología , Ácido Palmítico/metabolismo , Tapsigargina/farmacología , Humanos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Tiorredoxinas/metabolismo , Tiorredoxinas/genética , Supervivencia Celular/efectos de los fármacosRESUMEN
The incidence of nonalcoholic fatty liver disease (NAFLD), or metabolic dysfunction-associated fatty liver disease (MAFLD), is increasing in adults and children. Unfortunately, effective pharmacological treatments remain unavailable. Single nucleotide polymorphisms (SNPs) in the patatin-like phospholipase domain-containing protein (PNPLA3 I148M) have the most significant genetic association with the disease at all stages of its progression. A roadblock to identifying potential treatments for PNPLA3-induced NAFLD is the lack of a human cell platform that recapitulates the PNPLA3 I148M-mediated onset of lipid accumulation. Hepatocyte-like cells were generated from PNPLA3-/- and PNPLA3I148M/M-induced pluripotent stem cells (iPSCs). Lipid levels were measured by staining with BODIPY 493/503 and were found to increase in PNPLA3 variant iPSC-derived hepatocytes. A small-molecule screen identified multiple compounds that target Src/PI3K/Akt signaling and could eradicate lipid accumulation in these cells. We found that drugs currently in clinical trials for cancer treatment that target the same pathways also reduced lipid accumulation in PNPLA3 variant cells.