RESUMEN

The function of hydroxysteroid dehydrogenase 12 (HSD17B12) in lipid metabolism is poorly understood. To study this further, we created mice with hepatocyte-specific knockout of HSD17B12 (LiB12cKO). From 2 months on, these mice showed significant fat accumulation in their liver. As they aged, they also had a reduced whole-body fat percentage. Interestingly, the liver fat accumulation did not result in the typical formation of large lipid droplets (LD); instead, small droplets were more prevalent. Thus, LiB12KO liver did not show increased macrovesicular steatosis with the increasing fat content, while microvesicular steatosis was the predominant feature in the liver. This indicates a failure in the LD expansion. This was associated with liver damage, presumably due to lipotoxicity. Notably, the lipidomics data did not support an essential role of HSD17B12 in fatty acid (FA) elongation. However, we did observe a decrease in the quantity of specific lipid species that contain FAs with carbon chain lengths of 18 and 20 atoms, including oleic acid. Of these, phosphatidylcholine and phosphatidylethanolamine have been shown to play a key role in LD formation, and a limited amount of these lipids could be part of the mechanism leading to the dysfunction in LD expansion. The increase in the Cidec expression further supported the deficiency in LD expansion in the LiB12cKO liver. This protein is crucial for the fusion and growth of LDs, along with the downregulation of several members of the major urinary protein family of proteins, which have recently been shown to be altered during endoplasmic reticulum stress.

Asunto(s)

Hígado Graso , Hepatocitos , Gotas Lipídicas , Ratones Noqueados , Animales , Ratones , Gotas Lipídicas/metabolismo , Hepatocitos/metabolismo , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , 17-Hidroxiesteroide Deshidrogenasas/metabolismo , 17-Hidroxiesteroide Deshidrogenasas/genética , Metabolismo de los Lípidos , Peso Corporal , Hígado/metabolismo , Hígado/patología , Masculino , Ratones Endogámicos C57BL , Ácidos Grasos/metabolismo

RESUMEN

Metabolic dysfunction-associated diseases often refer to various diseases caused by metabolic problems such as glucose and lipid metabolism disorders. With the improvement of living standards, the increasing prevalence of metabolic diseases has become a severe public health problem, including metabolic dysfunction-associated steatotic liver disease (MASLD), alcohol-related liver disease (ALD), diabetes and obesity. These diseases are both independent and interdependent, with complex and diverse molecular mechanisms. Therefore, it is urgent to explore the molecular mechanisms and find effective therapeutic targets of these diseases. MicroRNAs (miRNAs) have emerged as key regulators of metabolic homoeostasis due to their multitargets and network regulatory properties within the past few decades. In this review, we discussed the latest progress in the roles of miRNA-mediated regulatory networks in the development and progression of MASLD, ALD, diabetes and obesity.

Asunto(s)

Enfermedades Metabólicas , MicroARNs , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Animales , Enfermedades Metabólicas/metabolismo , Enfermedades Metabólicas/terapia , Enfermedades Metabólicas/genética , Obesidad/metabolismo , Obesidad/genética , Diabetes Mellitus/metabolismo , Diabetes Mellitus/genética , Diabetes Mellitus/terapia , Hígado Graso/metabolismo , Hígado Graso/genética , Hígado Graso/terapia , Hígado Graso/etiología

RESUMEN

BACKGROUND: Abnormal lipid deposition is an important driver of the progression of metabolic dysfunction-associated steatotic liver disease (MASLD). MicroRNA-411-5p (miR-411-5p) and eukaryotic translation initiation factor 4γ2 (EIF4G2) are related to abnormal lipid deposition, but the specific mechanism is unknown. METHODS: A high-fat, high-cholesterol diet (HFHCD) and a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) and a high-fructose diet (HFrD) were used to establish MASLD rat and mouse models, respectively. MiR-411-5p agomir and mimic were used to upregulate the miR-411-5p in vivo and in vitro, respectively. Adeno-associated virus type 8 (AAV8) carrying EIF4G2 short hairpin RNA (shRNA) and small interfering RNA (siRNA) were used to downregulate the EIF4G2 expression in vivo and in vitro, respectively. Liver histopathological analysis, Biochemical analysis and other experiments were used to explore the functions of miR-411-5p and EIF4G2. RESULTS: MiR-411-5p was decreased in both MASLD rats and mice, and was negatively correlated with liver triglycerides and serum alanine transaminase (ALT) and aspartate transaminase (AST) levels. Upregulation of miR-411-5p alleviated liver lipid deposition and hepatocellular steatosis. Moreover, miR-411-5p targeted and downregulated EIF4G2. Downregulation of EIF4G2 not only reduced liver triglycerides and serum ALT and AST levels in MASLD model, but also alleviated lipid deposition. Notably, upregulation of miR-411-5p and downregulation of EIF4G2 led to the reduction of forkhead box class O3 (FOXO3) and inhibited the expression of sterol regulatory-element binding protein 1 (SREBP1), acetyl-CoA carboxylase 1 (ACC1) and fatty acid synthase (FASN), thereby reducing fatty acid synthesis. CONCLUSIONS: Upregulation of miR-411-5p inhibits EIF4G2 to reduce the FOXO3 expression, thereby reducing fatty acid synthesis and alleviating abnormal lipid deposition in MASLD.

Asunto(s)

Proteína Forkhead Box O3 , Metabolismo de los Lípidos , MicroARNs , Animales , MicroARNs/genética , MicroARNs/metabolismo , Ratones , Masculino , Ratas , Metabolismo de los Lípidos/genética , Proteína Forkhead Box O3/metabolismo , Proteína Forkhead Box O3/genética , Factor 4G Eucariótico de Iniciación/metabolismo , Factor 4G Eucariótico de Iniciación/genética , Ratones Endogámicos C57BL , Humanos , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Ratas Sprague-Dawley , Hígado/metabolismo , Hígado/patología

RESUMEN

The onset and progression mechanisms of metabolic dysfunction-associated steatotic liver disease (MASLD) and metabolic dysfunction-associated steatohepatitis (MASH) are being studied. We developed and analyzed a new mouse model of obesity by combining maternal Id-like molecule (Maid) and melanocortin-4 receptor (Mc4r) gene deletions. Four mice, each at 12 and 28 weeks of age, were analyzed for each genotype: Maid gene knockout, Mc4r gene knockout, combined Mc4r and Maid gene knockout, and Mc4r gene knockout with a high-fat diet. Mice with a combined deficiency of Mc4r and Maid gene showed significantly more severe obesity compared to all other genotypes, but no liver fibrosis or a decline in metabolic status were observed. In visceral white adipose tissue, Maid and Mc4r gene knockout mice had fewer CD11c-positive cells and lower mRNA expression of both inflammatory and anti-inflammatory cytokines. Furthermore, Maid and Mc4r gene knockout mice showed lower expression of adipocytokines in visceral white adipose tissue and uncoupling protein-1 in scapular brown adipose tissue. The expression of adipocytokines and uncoupling protein-1 is regulated by sympathetic nerve signaling that contribute severe obesity in Maid and Mc4r gene knockout mice. These mechanisms contribute hyperobesity in Maid and Mc4r gene knockout mice.

Asunto(s)

Inflamación , Ratones Noqueados , Obesidad , Receptor de Melanocortina Tipo 4 , Animales , Receptor de Melanocortina Tipo 4/genética , Receptor de Melanocortina Tipo 4/deficiencia , Receptor de Melanocortina Tipo 4/metabolismo , Obesidad/genética , Obesidad/metabolismo , Ratones , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Tejido Adiposo/metabolismo , Tejido Adiposo/patología , Masculino , Tejido Adiposo Pardo/metabolismo , Tejido Adiposo Pardo/patología , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Hígado Graso/genética , Hígado Graso/patología , Hígado Graso/metabolismo , Adipoquinas/metabolismo , Adipoquinas/genética , Tejido Adiposo Blanco/metabolismo , Tejido Adiposo Blanco/patología

RESUMEN

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.

Asunto(s)

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 Reductasa

RESUMEN

The endocannabinoid system (ECS) plays a crucial role in reproductive health, but its function in postpartum dairy cows remains poorly understood. This study investigated the expression patterns of ECS-related genes in the endometrium of postpartum dairy cows and their associations with endometrial health and the presence of fatty liver. Endometrial biopsies were collected from 22 Holstein Friesian cows at 4 and 7 weeks postpartum. Gene expression was analyzed using RT-qPCR, focusing on key ECS components including CNR2, MGLL, FAAH1, NAAA, NAPEPLD, PADI4 and PTGDS. The results reveal dynamic changes in ECS gene expression associated with endometritis and fatty liver. MGLL expression was significantly upregulated in cows with endometritis at 7 weeks postpartum, while NAAA expression was consistently downregulated in cows with fatty liver. CNR2 showed a time-dependent pattern in endometritis, and PTGDS expression was elevated in clinical endometritis at 4 weeks postpartum. The presence of fatty liver was associated with altered expression patterns of several ECS genes, suggesting a link between metabolic stress and endometrial ECS function. These findings indicate a potential role for the ECS in postpartum uterine health and recovery, offering new insights into the molecular mechanisms underlying reproductive disorders in dairy cows and paving the way for novel therapeutic approaches.

Asunto(s)

Enfermedades de los Bovinos , Endocannabinoides , Endometrio , Hígado Graso , Periodo Posparto , Animales , Femenino , Bovinos , Endometrio/metabolismo , Endometrio/patología , Endocannabinoides/metabolismo , Endocannabinoides/genética , Hígado Graso/genética , Hígado Graso/veterinaria , Hígado Graso/metabolismo , Periodo Posparto/genética , Periodo Posparto/metabolismo , Enfermedades de los Bovinos/genética , Enfermedades de los Bovinos/metabolismo , Endometritis/veterinaria , Endometritis/genética , Endometritis/metabolismo , Regulación de la Expresión Génica

RESUMEN

Recently, we have demonstrated that mice, cultured embryos in α-minimum essential medium (αMEM) and subsequent fed a high-fat, high-sugar diet, developed steatohepatitis. In this study, we investigated using these samples whether the expression of lipid droplet formation genes in the liver is higher in MEM mice, whether these expressions are regulated by histone acetylation, writers/readers of histone acetylation, and the transcriptional factors of endoplasmic reticulum stress. Mice were produced by two-cell embryos in αMEM or standard potassium simplex-optimized medium (control) in vitro for 48 h, and implanted into an oviduct for spontaneous delivery. MEM and control-mice were fed a high-fat, high-sugar diet for 18 wk, and then liver samples were collected and analyzed by histology, qRT-PCR, and chromatin immunoprecipitation assay. Gene expression of Cidea, Cidec, and Plin4 were higher in MEM mice and histone H3K9 acetylation, BRD4, and CBP were higher in MEM mice than in control mice around those genes. However, the binding of endoplasmic reticulum stress-related transcription factors (ATF4, CHOP and C/EBPα) around those genes in the liver, was not clearly differed between MEM mice and control mice. The increased expression of Cidea, Cidec and Plin4 in the liver, accompanied by the development of steatohepatitis in mice induced is positively associated with increased histone H3K9 acetylation and CBP and BRD4 binding around these genes.

Asunto(s)

Estrés del Retículo Endoplásmico , Hígado Graso , Histonas , Gotas Lipídicas , Hígado , Animales , Histonas/metabolismo , Acetilación , Gotas Lipídicas/metabolismo , Ratones , Femenino , Hígado/metabolismo , Hígado Graso/metabolismo , Hígado Graso/genética , Hígado Graso/etiología , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Dieta Alta en Grasa/efectos adversos , Factores de Transcripción/metabolismo , Factores de Transcripción/genética , Factor de Transcripción CHOP/metabolismo , Factor de Transcripción CHOP/genética , Proteínas Potenciadoras de Unión a CCAAT/metabolismo , Proteínas Potenciadoras de Unión a CCAAT/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/genética

RESUMEN

This study investigates novel short-lived long noncoding RNAs (lncRNAs) in mice with altered expression in metabolic dysfunction-associated steatotic liver (MASH) and liver fibrosis. LncRNAs share similarities with mRNAs in their transcription by RNA polymerase II, possession of a 5' cap structure, and presence of a polyA tail. We identified two lncRNAs, Kcnq1ot1 and Rmst, significantly decreased in both conditions. These lncRNAs showed dramatic expression changes in MASH livers induced by Western diets and CCl4, and in fibrotic livers induced by CCl4 alone. The decrease was more pronounced in liver fibrosis, suggesting their potential as biomarkers for disease progression. Our findings are consistent across different fibrosis models, indicating a crucial role for these lncRNAs in MASH and liver fibrosis in mice. With MASH becoming a global health issue and its progression to fibrosis associated with hepatocarcinogenesis and poor prognosis, understanding the underlying mechanisms is critical. This research contributes to elucidating lncRNA functions in murine liver diseases and provides a foundation for developing novel therapeutic strategies targeting lncRNAs in MASH and liver fibrosis, offering new avenues for potential therapeutic interventions.

Asunto(s)

Biomarcadores , Cirrosis Hepática , ARN Largo no Codificante , Animales , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ratones , Cirrosis Hepática/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Masculino , Canales de Potasio con Entrada de Voltaje/genética , Canales de Potasio con Entrada de Voltaje/metabolismo , Hepatopatías/genética , Hepatopatías/metabolismo , Hepatopatías/patología , Ratones Endogámicos C57BL , Enfermedad Crónica , Modelos Animales de Enfermedad , Hígado Graso/genética , Hígado Graso/metabolismo , Hígado Graso/patología

RESUMEN

Metabolic dysfunction-associated steatohepatitis (MASH) poses challenges for targeted delivery and retention of therapeutic proteins due to excess extracellular matrix (ECM). Here we present a new approach to treat MASH, termed "Fibrosis overexpression and retention (FORT)". In this strategy, we design (1) retinoid-derivative lipid nanoparticle (LNP) to enable enhanced mRNA overexpression in fibrotic regions, and (2) mRNA modifications which facilitate anchoring of therapeutic proteins in ECM. LNPs containing carboxyl-retinoids, rather than alcohol- or ester-retinoids, effectively deliver mRNA with over 10-fold enhancement of protein expression in fibrotic livers. The carboxyl-retinoid rearrangement on the LNP surface improves protein binding and membrane fusion. Therapeutic proteins are then engineered with an endogenous collagen-binding domain. These fusion proteins exhibit increased retention in fibrotic lesions and reduced systemic toxicity. In vivo, fibrosis-targeting LNPs encoding fusion proteins demonstrate superior therapeutic efficacy in three clinically relevant male-animal MASH models. This approach holds promise in fibrotic diseases unsuited for protein injection.

Asunto(s)

Nanopartículas , ARN Mensajero , Animales , Masculino , Nanopartículas/química , Humanos , Ratones , ARN Mensajero/genética , ARN Mensajero/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Cirrosis Hepática/terapia , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Matriz Extracelular/metabolismo , Ratones Endogámicos C57BL , Lípidos/química , Hígado Graso/genética , Hígado Graso/metabolismo , Hígado Graso/patología , Fibrosis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Liposomas

RESUMEN

BACKGROUND & AIMS: We previously identified subsets of patients with metabolic (dysfunction)-associated steatotic liver disease (MASLD) with different metabolic phenotypes. Here, we aimed to refine this classification based on genetic algorithms implemented in a Python package. The use of these genetic algorithms can help scientists to solve problems which cannot be solved with other methods. We present this package and its capabilities with specific problems. The name, PyGenMet, comes from its main goal, solving problems in Python with Genetic Algorithms and Metabolomics data. METHODS: We collected serum from methionine adenosyltransferase 1a knockout (Mat1a-KO) mice, which have chronically low level of hepatic S-adenosylmethionine (SAMe) and the metabolomes of all samples were determined. We also analyzed serum metabolomes of 541 patients with biopsy proven MASLD (182 with simple steatosis and 359 with metabolic (dysfunction)-associated steatohepatitis or MASH) and compared them with the serum metabolomes of this specific MASLD mouse model using Genetic Algorithms in order to select patients with a specific phenotype. RESULTS: By applying genetic algorithms, we have found a subgroup of patients with a lipid profile similar to that observed in the mouse model. When analyzing the two groups of patients, we have seen that patients with a lipid profile reflecting the mouse model characteristics show significant differences in lipoproteins, especially in LDL-4, LDL-5, and LDL-6 associated with atherogenic risk. CONCLUSION: The results show that the application of genetic algorithms to subclassify patients with MASLD (or other metabolic disease) give consistent results and are a good approximation for the treatment of large volumes of data such as those from omics sciences and patient classification.

Asunto(s)

Algoritmos , Modelos Animales de Enfermedad , Hígado Graso , Ratones Noqueados , Animales , Ratones , Hígado Graso/genética , Hígado Graso/metabolismo , Humanos , Metabolómica , Metaboloma , Masculino , Investigación Biomédica Traslacional , Metionina Adenosiltransferasa/genética , Metionina Adenosiltransferasa/metabolismo

RESUMEN

Progression of metabolic dysfunction-associated steatites liver disease (MASLD) to steatohepatitis (MASH) is driven by stress-inducing lipids that promote liver inflammation and fibrosis, and MASH can lead to cirrhosis and hepatocellular carcinoma. Previously, we showed coordinated defenses regulated by transcription factors, nuclear factor erythroid 2-related factor-1 (Nrf1) and -2 (Nrf2), protect against hepatic lipid stress. Here, we investigated protective effects of hepatocyte Nrf1 and Nrf2 against MASH-linked liver fibrosis and tumorigenesis. Male and female mice with flox alleles for genes encoding Nrf1 (Nfe2l1), Nrf2 (Nfe2l2), or both were fed a MASH-inducing diet enriched with high fat, fructose, and cholesterol (HFFC) or a control diet for 24-52 weeks. During this period, hepatocyte Nrf1, Nrf2, or combined deficiency for ~7 days, ~7 weeks, and ~35 weeks was induced by administering mice hepatocyte-targeting adeno-associated virus (AAV) expressing Cre recombinase. The effects on MASH, markers of liver fibrosis and proliferation, and liver tumorigenesis were compared to control mice receiving AAV-expressing green fluorescent protein. Also, to assess the impact of Nrf1 and Nrf2 induction on liver fibrosis, HFFC diet-fed C57bl/6J mice received weekly injections of carbon tetrachloride, and from week 16 to 24, mice were treated with the Nrf2-activating drug bardoxolone, hepatocyte overexpression of human NRF1 (hNRF1), or both, and these groups were compared to control. Compared to the control diet, 24-week feeding with the HFFC diet increased bodyweight as well as liver weight, steatosis, and inflammation. It also increased hepatocyte proliferation and a marker of liver damage, p62. Hepatocyte Nrf1 and combined deficiency increased liver steatosis in control diet-fed but not HFFC diet-fed mice, and increased liver inflammation under both diet conditions. Hepatocyte Nrf1 deficiency also increased hepatocyte proliferation, whereas combined deficiency did not, and this also occurred for p62 level in control diet-fed conditions. In 52-week HFFC diet-fed mice, 35 weeks of hepatocyte Nrf1 deficiency, but not combined deficiency, resulted in more liver tumors in male mice, but not in female mice. In contrast, hepatocyte Nrf2 deficiency had no effect on any of these parameters. However, in the 15-week CCL4-exposed and 24-week HFFC diet-fed mice, Nrf2 induction with bardoxolone reduced liver steatosis, inflammation, fibrosis, and proliferation. Induction of hepatic Nrf1 activity with hNRF1 enhanced the effect of bardoxolone on steatosis and may have stimulated liver progenitor cells. Physiologic Nrf1 delays MASLD progression, Nrf2 induction alleviates MASH, and combined enhancement synergistically protects against steatosis and may facilitate liver repair.

Asunto(s)

Hepatocitos , Factor 2 Relacionado con NF-E2 , Animales , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Ratones , Hepatocitos/metabolismo , Masculino , Femenino , Progresión de la Enfermedad , Ratones Endogámicos C57BL , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patología , Factor 1 Relacionado con NF-E2/metabolismo , Factor 1 Relacionado con NF-E2/genética , Factor Nuclear 1 de Respiración/metabolismo , Factor Nuclear 1 de Respiración/genética , Dieta Alta en Grasa/efectos adversos , Hígado/metabolismo , Hígado/patología , Humanos

RESUMEN

Mexican Americans are disproportionally affected by metabolic dysfunction-associated steatotic liver disease (MASLD), which often co-occurs with diabetes. Despite extensive evidence on the causative role of the gut microbiome in MASLD, studies determining the involvement of the gut phageome are scarce. In this cross-sectional study, we characterized the gut phageome in Mexican Americans of South Texas by stool shotgun metagenomic sequencing of 340 subjects, concurrently screened for liver steatosis by transient elastography. Inter-individual variations in the phageome were associated with gender, country of birth, diabetes, and liver steatosis. The phage signatures for diabetes and liver steatosis were subsequently determined. Enrichment of Inoviridae was associated with both diabetes and liver steatosis. Diabetes was further associated with the enrichment of predominantly temperate Escherichia phages, some of which possessed virulence factors. Liver steatosis was associated with the depletion of Lactococcus phages r1t and BK5-T, and enrichment of the globally prevalent Crassvirales phages, including members of genus cluster IX (Burzaovirus coli, Burzaovirus faecalis) and VI (Kahnovirus oralis). The Lactococcus phages showed strong correlations and co-occurrence with Lactococcus lactis, while the Crassvirales phages, B. coli, B. faecalis, and UAG-readthrough crAss clade correlated and co-occurred with Prevotella copri. In conclusion, we identified the gut phageome signatures for two closely linked metabolic diseases with significant global burden. These phage signatures may have utility in risk modeling and disease prevention in this high-risk population, and identification of potential bacterial targets for phage therapy.IMPORTANCEPhages influence human health and disease by shaping the gut bacterial community. Using stool samples from a high-risk Mexican American population, we provide insights into the gut phageome changes associated with diabetes and liver steatosis, two closely linked metabolic diseases with significant global burden. Common to both diseases was an enrichment of Inoviridae, a group of phages that infect bacterial hosts chronically without lysis, allowing them to significantly influence bacterial growth, virulence, motility, biofilm formation, and horizontal gene transfer. Diabetes was additionally associated with the enrichment of Escherichia coli-infecting phages, some of which contained virulence factors. Liver steatosis was additionally associated with the depletion of Lactococcus lactis-infecting phages, and enrichment of Crassvirales phages, a group of virulent phages with high global prevalence and persistence across generations. These phageome signatures may have utility in risk modeling, as well as identify potential bacterial targets for phage therapy.

Asunto(s)

Bacteriófagos , Hígado Graso , Microbioma Gastrointestinal , Americanos Mexicanos , Viroma , Humanos , Masculino , Femenino , Microbioma Gastrointestinal/genética , Bacteriófagos/genética , Persona de Mediana Edad , Viroma/genética , Hígado Graso/genética , Estudios Transversales , Adulto , Diabetes Mellitus , Heces/microbiología , Heces/virología , Anciano

RESUMEN

PURPOSE: The causal relationship between life course adiposity with metabolic dysfunction-associated steatotic liver disease (MASLD) is ambiguous. We aimed to investigate whether there is an independent genetic causal relationship between body size at various life course and MASLD. METHODS: We performed univariable and multivariable Mendelian randomization (MR) to estimate the causal effect of body size at different life stages on MASLD (i.e., defined by the clinical comprehensive diagnosis from the electronic health record [HER] codes [ICD9/ICD10] or diagnostic phrases), including birthweight, childhood body mass index (BMI), adult BMI, waist circumference (WC), waist-to-hip ratio (WHR), body fat percentage (BFP). RESULTS: In univariate analyses, higher genetically predicted lower birthweight (ORIVW = 0.61, 95%CI, 0.52 to 0.74), Childhood BMI ( ORIVW = 1.37, 95%CI, 1.12 to 1.64), and adult BMI (ORIVW = 1.41, 95%CI, 1.27 to 1.57) was significantly associated with subsequent risk of MASLD after Bonferroni correction. The MVMR analysis demonstrated compelling proof that birthweight and adult BMI had a direct causal relationship with MASLD. However, after adjusting for birthweight and adult BMI, the direct causal relationship between childhood BMI and MASLD disappeared. CONCLUSION: For the first time, this MR elucidated new evidence for the effect of life course adiposity on MASLD risk, providing lower birthweight and duration of obesity are independent risk factors for MASLD. Our findings indicated that weight management during distinct time periods plays a significant role in the prevention and treatment of MASLD.

Asunto(s)

Adiposidad , Peso al Nacer , Índice de Masa Corporal , Análisis de la Aleatorización Mendeliana , Humanos , Adulto , Adiposidad/genética , Niño , Factores de Riesgo , Hígado Graso/genética , Femenino , Masculino , Circunferencia de la Cintura

RESUMEN

While macrophage heterogeneity during metabolic dysfunction-associated steatohepatitis (MASH) has been described, the fate of these macrophages during MASH regression is poorly understood. Comparing macrophage heterogeneity during MASH progression vs regression, we identified specific macrophage subpopulations that are critical for MASH/fibrosis resolution. We elucidated the restorative pathways and gene signatures that define regression-associated macrophages and establish the importance of TREM2+ macrophages during MASH regression. Liver-resident Kupffer cells are lost during MASH and are replaced by four distinct monocyte-derived macrophage subpopulations. Trem2 is expressed in two macrophage subpopulations: i) monocyte-derived macrophages occupying the Kupffer cell niche (MoKC) and ii) lipid-associated macrophages (LAM). In regression livers, no new transcriptionally distinct macrophage subpopulation emerged. However, the relative macrophage composition changed during regression compared to MASH. While MoKC was the major macrophage subpopulation during MASH, they decreased during regression. LAM was the dominant macrophage subtype during MASH regression and maintained Trem2 expression. Both MoKC and LAM were enriched in disease-resolving pathways. Absence of TREM2 restricted the emergence of LAMs and formation of hepatic crown-like structures. TREM2+ macrophages are functionally important not only for restricting MASH-fibrosis progression but also for effective regression of inflammation and fibrosis. TREM2+ macrophages are superior collagen degraders. Lack of TREM2+ macrophages also prevented elimination of hepatic steatosis and inactivation of HSC during regression, indicating their significance in metabolic coordination with other cell types in the liver. TREM2 imparts this protective effect through multifactorial mechanisms, including improved phagocytosis, lipid handling, and collagen degradation.

Asunto(s)

Macrófagos del Hígado , Cirrosis Hepática , Macrófagos , Glicoproteínas de Membrana , Receptores Inmunológicos , Receptores Inmunológicos/metabolismo , Receptores Inmunológicos/genética , Glicoproteínas de Membrana/metabolismo , Glicoproteínas de Membrana/genética , Animales , Ratones , Macrófagos/metabolismo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Cirrosis Hepática/genética , Macrófagos del Hígado/metabolismo , Hígado/metabolismo , Hígado/patología , Metabolismo de los Lípidos , Ratones Endogámicos C57BL , Masculino , Lípidos , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , Ratones Noqueados

RESUMEN

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 imagen

RESUMEN

BACKGROUND: Existing studies have presented limited and disparate findings on the nexus between immune cells, plasma metabolites, and metabolic dysfunction-associated steatotic liver disease (MASLD). The aim of this study was to investigate the causal relationship between immune cells and MASLD. Additionally, we aimed to identify and quantify the potential mediating role of metabolites. METHODS: A Mendelian randomization (MR) analysis was conducted using two samples of pooled data from genome-wide association studies on MASLD that included 2568 patients and 409,613 control individuals. Additionally, a mediated MR study was employed to quantify the metabolite-mediated immune cell effects on MASLD. RESULTS: In this study, eight immunophenotypes were linked to the risk of MASLD, and thirty-five metabolites/metabolite ratios were linked to the occurrence of MASLD. Furthermore, a total of six combinations of immunophenotypic and metabolic factors demonstrated effects on the occurrence of MASLD, although the mediating effects of metabolites were not significant. CONCLUSION: Our study demonstrated that certain immunophenotypes and metabolite/metabolite ratios have independent causal relationships with MASLD. Furthermore, we identified specific metabolites/metabolite ratios that are associated with an increased risk of MASLD. However, their mediating role in the causal association between immunophenotypes and MASLD was not significant. It is important to consider immune and metabolic disorders among patients with MASLD in clinical practice.

Asunto(s)

Estudio de Asociación del Genoma Completo , Análisis de la Aleatorización Mendeliana , Humanos , Polimorfismo de Nucleótido Simple , Hígado Graso/genética , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/inmunología , Inmunofenotipificación , Masculino

RESUMEN

This study investigates sex-specific effects in a gain-of-function model to evaluate Nfil3 function in relation to high-fat diet (HFD)-induced metabolic dysfunction-associated steatotic liver disease (MASLD) and gut microbiota (GM)-induced alterations in the bile acid (BA) profile. MASLD is induced in both wild type and Nfil3-deficient (NKO) C57BL/6 J mice through an HFD. The hepatic immune response is evaluated using flow cytometry, revealing that NKO mice exhibit lower body weight, serum triglyceride (TG) levels, tissue injury, inflammation, and fat accumulation. The Nfil3 deletion reduces macrophage counts in fibrotic liver tissues, decreases proinflammatory gene and protein expression, and diminishes gut barrier function. Alpha and beta diversity analysis reveal increased GM alpha diversity across different sexes. The Nfil3 gene deletion modifies the BA profile, suggesting that negative feedback through the Nfil3-FXR-FGF15 axis facilitates BA recycling from the liver via enterohepatic circulation. Therefore, inhibiting Nfil3 in the liver offers a viable treatment approach for MASLD.

Asunto(s)

Dieta Alta en Grasa , Ratones Endogámicos C57BL , Ratones Noqueados , Animales , Ratones , Masculino , Femenino , Dieta Alta en Grasa/efectos adversos , Microbioma Gastrointestinal , Ácidos y Sales Biliares/metabolismo , Hígado/metabolismo , Hígado/patología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/patología , Modelos Animales de Enfermedad , Hígado Graso/metabolismo , Hígado Graso/genética , Hígado Graso/patología , Hígado Graso/etiología , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico

RESUMEN

Hepatic adipogenesis has common mechanisms with adipocyte differentiation such as PPARγ involvement and the induction of adipose tissue-specific molecules. A previous report demonstrated that integrator complex subunit 6 (INTS6) is required for adipocyte differentiation. This study aimed to investigate INTS6 expression and its role in hepatic steatosis progression. The expression of INTS6 and PPARγ was examined in the liver of a mouse model of steatohepatitis and in paired liver biopsy samples from 11 patients with severe obesity and histologically proven metabolic dysfunction associated steatohepatitis (MASH) before and one year after bariatric surgery. To induce hepatocellular steatosis in vitro, an immortalized human hepatocyte cell line Hc3716 was treated with free fatty acids. In the steatohepatitis mouse model, we observed hepatic induction of INTS6, PPARγ, and adipocyte-specific genes. In contrast, ß-catenin which negatively regulates PPARγ was reduced. Biopsied human livers demonstrated a strong positive correlation (r2 = 0.8755) between INTS6 and PPARγ mRNA levels. After bariatric surgery, gene expressions of PPARγ, FABP4, and CD36 were mostly downregulated. In our in vitro experiments, we observed a concentration-dependent increase in Oil Red O staining in Hc3716 cells after treatment with the free fatty acids. Alongside this change, the expression of INTS6, PPARγ, and adipocyte-specific genes was induced. INTS6 knockdown using siRNA significantly suppressed cellular lipid accumulation together with induction of ß-catenin and PPARγ downregulation. Collectively, INTS6 expression closely correlates with PPARγ. INTS6 suppression significantly reduced hepatocyte steatosis via ß-catenin-PPARγ axis, indicating that INTS6 could be a novel therapeutic target for treating MASH.

Asunto(s)

PPAR gamma , beta Catenina , PPAR gamma/metabolismo , PPAR gamma/genética , Humanos , Animales , beta Catenina/metabolismo , beta Catenina/genética , Ratones , Masculino , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , Femenino , Hepatocitos/metabolismo , Hepatocitos/patología , Línea Celular , Ratones Endogámicos C57BL , Modelos Animales de Enfermedad , Hígado/metabolismo , Hígado/patología , Persona de Mediana Edad , Adulto , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/genética , Antígenos CD36/metabolismo , Antígenos CD36/genética

RESUMEN

Background: The development of obesity-associated comorbidities such as type 2 diabetes (T2D) and hepatic steatosis has been linked to selected microRNAs in individual studies; however, an unbiased genome-wide approach to map T2D induced changes in the miRNAs landscape in human liver samples, and a subsequent robust identification and validation of target genes are still missing. Methods: Liver biopsies from age- and gender-matched obese individuals with (n=20) or without (n=20) T2D were used for microRNA microarray analysis. The candidate microRNA and target genes were validated in 85 human liver samples, and subsequently mechanistically characterized in hepatic cells as well as by dietary interventions and hepatic overexpression in mice. Results: Here, we present the human hepatic microRNA transcriptome of type 2 diabetes in liver biopsies and use a novel seed prediction tool to robustly identify microRNA target genes, which were then validated in a unique cohort of 85 human livers. Subsequent mouse studies identified a distinct signature of T2D-associated miRNAs, partly conserved in both species. Of those, human-murine miR-182-5 p was the most associated with whole-body glucose homeostasis and hepatic lipid metabolism. Its target gene LRP6 was consistently lower expressed in livers of obese T2D humans and mice as well as under conditions of miR-182-5 p overexpression. Weight loss in obese mice decreased hepatic miR-182-5 p and restored Lrp6 expression and other miR-182-5 p target genes. Hepatic overexpression of miR-182-5 p in mice rapidly decreased LRP6 protein levels and increased liver triglycerides and fasting insulin under obesogenic conditions after only seven days. Conclusions: By mapping the hepatic miRNA-transcriptome of type 2 diabetic obese subjects, validating conserved miRNAs in diet-induced mice, and establishing a novel miRNA prediction tool, we provide a robust and unique resource that will pave the way for future studies in the field. As proof of concept, we revealed that the repression of LRP6 by miR-182-5 p, which promotes lipogenesis and impairs glucose homeostasis, provides a novel mechanistic link between T2D and non-alcoholic fatty liver disease, and demonstrate in vivo that miR-182-5 p can serve as a future drug target for the treatment of obesity-driven hepatic steatosis. Funding: This work was supported by research funding from the Deutsche Forschungsgemeinschaft (KI 1887/2-1, KI 1887/2-2, KI 1887/3-1 and CRC-TR296), the European Research Council (ERC, CoG Yoyo LepReSens no. 101002247; PTP), the Helmholtz Association (Initiative and Networking Fund International Helmholtz Research School for Diabetes; MB) and the German Center for Diabetes Research (DZD Next Grant 82DZD09D1G).

Asunto(s)

Diabetes Mellitus Tipo 2 , Hígado , MicroARNs , Obesidad , Transcriptoma , MicroARNs/metabolismo , MicroARNs/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Animales , Humanos , Obesidad/genética , Obesidad/metabolismo , Hígado/metabolismo , Ratones , Masculino , Hígado Graso/genética , Hígado Graso/metabolismo , Femenino , Ratones Endogámicos C57BL , Persona de Mediana Edad , Perfilación de la Expresión Génica

RESUMEN

High-laying ducks are often fed high-energy, nutritious feeds to maintain high productivity, which predisposes them to lipid metabolism disorders and the development of fatty liver syndrome (FLS), which seriously affects production performance and has a substantial economic impact on the poultry industry. Therefore, it is necessary to elucidate the mechanisms underlying the development of fatty liver syndrome. In this study, seven Shan Partridge ducks, each with fatty liver syndrome and normal laying ducks, were selected, and Hematoxylin Eosin staining (HE staining), Masson staining, and transcriptome sequencing were performed on liver tissue. In addition to exploring key genes and pathways using conventional analysis methods, we constructed the first Kyoto Encyclopedia of Genes and Genomes (KEGG) database-based predefined gene set containing 12,764 pathways and 16,836 genes and further performed gene set enrichment analysis (GSEA) on the liver transcriptome data. Finally, key nodes and biological processes were identified via the protein-protein interaction (PPI) network. The results showed that the liver in the FL group exhibited steatosis and fibrosis, and a total of 3,663 genes with upregulated expression versus 2,296 downregulated genes were screened by conventional analysis. GSEA analysis and PPI network analysis revealed that the liver in the FL group exhibited disruption of the mitochondrial electron transport chain, leading to decreased oxidative phosphorylation and the secretion of excessive proinflammatory factors amid the continuous accumulation of lipids. Under continuous chronic inflammation, cell cycle arrest triggers apoptosis, while fibrosis becomes more severe, and procarcinogenic genes are activated, leading to the continuous development and deterioration of the liver. In conclusion, the predefined gene set constructed in this study can be used for GSEA, and the identified hub genes provide useful reference data and a solid foundation for the study of the genetic regulatory mechanism of fatty liver syndrome in ducks.

Asunto(s)

Patos , Hígado Graso , Enfermedades de las Aves de Corral , Transcriptoma , Animales , Patos/genética , Enfermedades de las Aves de Corral/genética , Hígado Graso/veterinaria , Hígado Graso/genética , Femenino , Mapas de Interacción de Proteínas , Perfilación de la Expresión Génica/veterinaria