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1.
Cell ; 175(5): 1289-1306.e20, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30454647

RESUMO

Obesity is a major driver of cancer, especially hepatocellular carcinoma (HCC). The prevailing view is that non-alcoholic steatohepatitis (NASH) and fibrosis or cirrhosis are required for HCC in obesity. Here, we report that NASH and fibrosis and HCC in obesity can be dissociated. We show that the oxidative hepatic environment in obesity inactivates the STAT-1 and STAT-3 phosphatase T cell protein tyrosine phosphatase (TCPTP) and increases STAT-1 and STAT-3 signaling. TCPTP deletion in hepatocytes promoted T cell recruitment and ensuing NASH and fibrosis as well as HCC in obese C57BL/6 mice that normally do not develop NASH and fibrosis or HCC. Attenuating the enhanced STAT-1 signaling prevented T cell recruitment and NASH and fibrosis but did not prevent HCC. By contrast, correcting STAT-3 signaling prevented HCC without affecting NASH and fibrosis. TCPTP-deletion in hepatocytes also markedly accelerated HCC in mice treated with a chemical carcinogen that promotes HCC without NASH and fibrosis. Our studies reveal how obesity-associated hepatic oxidative stress can independently contribute to the pathogenesis of NASH, fibrosis, and HCC.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/patologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Carcinoma Hepatocelular/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Hepatócitos/metabolismo , Humanos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Estresse Oxidativo , Proteína Tirosina Fosfatase não Receptora Tipo 2/deficiência , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Transdução de Sinais
2.
Mol Cell ; 82(8): 1528-1542.e10, 2022 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-35245436

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a global health concern with no approved drugs. High-protein dietary intervention is currently the most effective treatment. However, its underlying mechanism is unknown. Here, using Drosophila oenocytes, the specialized hepatocyte-like cells, we find that dietary essential amino acids ameliorate hepatic steatosis by inducing polyubiquitination of Plin2, a lipid droplet-stabilizing protein. Leucine and isoleucine, two branched-chain essential amino acids, strongly bind to and activate the E3 ubiquitin ligase Ubr1, targeting Plin2 for degradation. We further show that the amino acid-induced Ubr1 activity is necessary to prevent steatosis in mouse livers and cultured human hepatocytes, providing molecular insight into the anti-NAFLD effects of dietary protein/amino acids. Importantly, split-intein-mediated trans-splicing expression of constitutively active UBR2, an Ubr1 family member, significantly ameliorates obesity-induced and high fat diet-induced hepatic steatosis in mice. Together, our results highlight activation of Ubr1 family proteins as a promising strategy in NAFLD treatment.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Aminoácidos Essenciais/metabolismo , Aminoácidos Essenciais/farmacologia , Aminoácidos Essenciais/uso terapêutico , Animais , Dieta Hiperlipídica/efeitos adversos , Hepatócitos/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Ubiquitinação
3.
Annu Rev Physiol ; 85: 363-381, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36260807

RESUMO

Insulin action is impaired in type 2 diabetes. The functions of the hormone are an integrated product of insulin secretion from pancreatic ß-cells and insulin clearance by receptor-mediated endocytosis and degradation, mostly in liver (hepatocytes) and, to a lower extent, in extrahepatic peripheral tissues. Substantial evidence indicates that genetic or acquired abnormalities of insulin secretion or action predispose to type 2 diabetes. In recent years, along with the discovery of the molecular foundation of receptor-mediated insulin clearance, such as through the membrane glycoprotein CEACAM1, a consensus has begun to emerge that reduction of insulin clearance contributes to the disease process. In this review, we consider the evidence suggesting a pathogenic role for reduced insulin clearance in insulin resistance, obesity, hepatic steatosis, and type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica , Humanos , Insulina/metabolismo , Fígado/metabolismo , Obesidade , Hepatopatia Gordurosa não Alcoólica/metabolismo
4.
Proc Natl Acad Sci U S A ; 120(4): e2217543120, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36669104

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease, in which prognosis is determined by liver fibrosis. A common variant in hydroxysteroid 17-beta dehydrogenase 13 (HSD17B13, rs72613567-A) is associated with a reduced risk of fibrosis in NAFLD, but the underlying mechanism(s) remains unclear. We investigated the effects of this variant in the human liver and in Hsd17b13 knockdown in mice by using a state-of-the-art metabolomics approach. We demonstrate that protection against liver fibrosis conferred by the HSD17B13 rs72613567-A variant in humans and by the Hsd17b13 knockdown in mice is associated with decreased pyrimidine catabolism at the level of dihydropyrimidine dehydrogenase. Furthermore, we show that hepatic pyrimidines are depleted in two distinct mouse models of NAFLD and that inhibition of pyrimidine catabolism by gimeracil phenocopies the HSD17B13-induced protection against liver fibrosis. Our data suggest pyrimidine catabolism as a therapeutic target against the development of liver fibrosis in NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Camundongos , Fígado/metabolismo , Cirrose Hepática/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Pirimidinas/farmacologia , Pirimidinas/metabolismo
5.
Annu Rev Pharmacol Toxicol ; 62: 155-175, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34516292

RESUMO

While the uses of retinoids for cancer treatment continue to evolve, this review focuses on other therapeutic areas in which retinoids [retinol (vitamin A), all-trans retinoic acid (RA), and synthetic retinoic acid receptor (RAR)α-, ß-, and γ-selective agonists] are being used and on promising new research that suggests additional uses for retinoids for the treatment of disorders of the kidneys, skeletal muscles, heart, pancreas, liver, nervous system, skin, and other organs. The most mature area, in terms of US Food and Drug Administration-approved, RAR-selective agonists, is for treatment of various skin diseases. Synthetic retinoid agonists have major advantages over endogenous RAR agonists such as RA. Because they act through a specific RAR, side effects may be minimized, and synthetic retinoids often have better pharmaceutical properties than does RA. Based on our increasing knowledge of the multiple roles of retinoids in development, epigenetic regulation, and tissue repair, other exciting therapeutic areas are emerging.


Assuntos
Neoplasias , Retinoides , Epigênese Genética , Humanos , Neoplasias/tratamento farmacológico , Receptores do Ácido Retinoico/genética , Receptores do Ácido Retinoico/metabolismo , Receptores X de Retinoides , Retinoides/farmacologia , Retinoides/uso terapêutico , Estados Unidos
6.
Proc Natl Acad Sci U S A ; 119(10): e2200083119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35238641

RESUMO

SignificanceWhile increasing evidence associates the disruption of circadian rhythms with pathologic conditions, including obesity, type 2 diabetes, and nonalcoholic fatty liver diseases (NAFLD), the involved mechanisms are still poorly described. Here, we show that, in both humans and mice, the pathogenesis of NAFLD is associated with the disruption of the circadian clock combined with perturbations of the growth hormone and sex hormone pathways. However, while this condition protects mice from the development of fibrosis and insulin resistance, it correlates with increased fibrosis in humans. This suggests that the perturbation of the circadian clock and its associated disruption of the growth hormone and sex hormone pathways are critical for the pathogenesis of metabolic and liver diseases.


Assuntos
Fatores de Transcrição ARNTL/fisiologia , Relógios Circadianos , Resistência à Insulina , Hepatopatia Gordurosa não Alcoólica/etiologia , Fatores de Transcrição ARNTL/genética , Animais , Dieta Hiperlipídica , Deleção de Genes , Regulação da Expressão Gênica , Humanos , Leptina/genética , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade/genética
7.
Semin Cancer Biol ; 93: 20-35, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37149203

RESUMO

Hepatocellular carcinoma (HCC) is estimated to be the third leading cause of cancer-related mortality and is characterized by low survival rates. Nonalcoholic fatty liver disease (NAFLD) is emerging as a leading cause of HCC, whose rates are increasing, owing to the increasing prevalence of NAFLD. The pathogenesis of NAFLD-associated HCC is multifactorial: insulin resistance, obesity, diabetes and the low-grade hepatic inflammation, which characterizes NAFLD, seem to play key roles in the development and progression of HCC. The diagnosis of NAFLD-associated HCC is based on imaging in the presence of liver cirrhosis, preferably computerized tomography or magnetic resonance imaging, but liver biopsy for histological confirmation is usually required in the absence of liver cirrhosis. Some preventive measures have been recommended for NAFLD-associated HCC, including weight loss, cessation of even moderate alcohol drinking and smoking, as well as the use of metformin, statins and aspirin. However, these preventive measures are mainly based on observational studies, thus they need validation in trials of different design before introducing in clinical practice. The treatment of NAFLD should be tailored on an individual basis and should be ideally determined by a multidisciplinary team. In the last two decades, new medications, including tyrosine kinase inhibitors and immune checkpoints inhibitors, have improved the survival of patients with advanced HCC, but trials specifically designed for patients with NAFLD-associated HCC are scarce. The aim of this review was to overview evidence on the epidemiology and pathophysiology of NAFLD-associated HCC, then to comment on imaging tools for its appropriate screening and diagnosis, and finally to critically summarize the currently available options for its prevention and treatment.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Hepatopatia Gordurosa não Alcoólica , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/etiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/etiologia , Progressão da Doença , Cirrose Hepática/complicações , Cirrose Hepática/patologia
8.
Med Res Rev ; 44(2): 568-586, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37899676

RESUMO

Nonalcoholic fatty liver disease, also called metabolic dysfunction-associated steatotic liver disease, is the most common liver disease worldwide and has no approved pharmacotherapy. Due to its beneficial effects on metabolic regulation, inflammation suppression, cell death prevention, and fibrogenesis inhibition, farnesoid X receptor (FXR) is widely accepted as a promising therapeutic target for nonalcoholic steatosis (NASH) or called metabolic dysfunction-associated steatohepatitis (MASH). Many FXR agonists have been developed for NASH/MASH therapy. Obeticholic acid (OCA) is the pioneering frontrunner FXR agonist and the first demonstrating success in clinical trials. Unfortunately, OCA did not receive regulatory approval as a NASH pharmacotherapy because its moderate benefits did not outweigh its safety risks, which may cast a shadow over FXR-based drug development for NASH/MASH. This review summarizes the milestones in the development of OCA for NASH/MASH and discuss its limitations, including moderate hepatoprotection and the undesirable side effects of dyslipidemia, pruritus, cholelithiasis, and liver toxicity risk, in depth. More importantly, we provide perspectives on FXR-based therapy for NASH/MASH, hoping to support a successful bench-to-clinic transition.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Ácido Quenodesoxicólico/farmacologia , Ácido Quenodesoxicólico/uso terapêutico
9.
J Lipid Res ; : 100580, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901559

RESUMO

This study aimed to determine whether obese men with nonalcoholic fatty liver disease (NAFLD) display differences between those with simple steatosis vs. steatohepatitis (NASH) in splanchnic and hepatic FFA and VLDL-triglycerides (VLDL-TG) balances. The study involved 17 obese men with biopsy-proven NAFLD (9 with NASH and 8 with simple steatosis). We used hepatic vein catheterization in combination with [3H]palmitate and [14C]VLDL-TG tracers to measure splanchnic palmitate and VLDL-TG uptake and release rates during basal and hyperinsulinemic conditions. Indocyanine green was used to measure splanchnic plasma flow. Splanchnic palmitate uptake was similar in the two groups and significantly reduced during hyperinsulinemia (NASH: 62 (48-77) vs. 38 (18-58) µmol/min; simple steatosis: 62 (46-78) vs. 45 (25-65) µmol/min, mean (95% CI), basal vs. clamp periods, respectively, p = 0.02 time-effect). Splanchnic palmitate release was also comparable between groups and non-significantly diminished during hyperinsulinemia. The percent palmitate delivered to the liver originating from visceral adipose tissue (VAT) lipolysis was similar and unchanged by hyperinsulinemia. Splanchnic uptake and release of VLDL-TG were similar between groups. Hyperinsulinemia suppressed VLDL-TG release (p <0.05 time-effect) in both groups. Insulin mediated glucose disposal was similar in the two groups (p = 0.54). IN CONCLUSIONS: Obese men with NASH and simple steatosis have similar splanchnic uptake and release of FFA and VLDL-TG and a similar proportion of FFA from VAT lipolysis delivered to the liver. These results suggest that FFA and VLDL-TG splanchnic balances are unaffected by NAFLD severity.

10.
J Lipid Res ; 65(6): 100558, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38729350

RESUMO

Metabolic dysfunction-associated steatotic liver disease is the most common form of liver disease and poses significant health risks to patients who progress to metabolic dysfunction-associated steatohepatitis. Fatty acid overload alters endoplasmic reticulum (ER) calcium stores and induces mitochondrial oxidative stress in hepatocytes, leading to hepatocellular inflammation and apoptosis. Obese mice have impaired liver sarco/ER Ca2+-ATPase (SERCA) function, which normally maintains intracellular calcium homeostasis by transporting Ca2+ ions from the cytoplasm to the ER. We hypothesized that restoration of SERCA activity would improve diet-induced steatohepatitis in mice by limiting ER stress and mitochondrial dysfunction. WT and melanocortin-4 receptor KO (Mc4r-/-) mice were placed on either chow or Western diet (WD) for 8 weeks. Half of the WD-fed mice were administered CDN1163 to activate SERCA, which reduced liver fibrosis and inflammation. SERCA activation also restored glucose tolerance and insulin sensitivity, improved histological markers of metabolic dysfunction-associated steatohepatitis, increased expression of antioxidant enzymes, and decreased expression of oxidative stress and ER stress genes. CDN1163 decreased hepatic citric acid cycle flux and liver pyruvate cycling, enhanced expression of mitochondrial respiratory genes, and shifted hepatocellular [NADH]/[NAD+] and [NADPH]/[NADP+] ratios to a less oxidized state, which was associated with elevated PUFA content of liver lipids. In sum, the data demonstrate that pharmacological SERCA activation limits metabolic dysfunction-associated steatotic liver disease progression and prevents metabolic dysfunction induced by WD feeding in mice.


Assuntos
Fígado , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático , Animais , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Camundongos , Fígado/metabolismo , Fígado/patologia , Masculino , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Estresse do Retículo Endoplasmático , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Dieta Ocidental/efeitos adversos , Camundongos Knockout
11.
J Proteome Res ; 23(6): 2253-2264, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38698681

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has emerged as the predominant chronic liver condition globally, and underdiagnosis is common, particularly in mild cases, attributed to the asymptomatic nature and traditional ultrasonography's limited sensitivity to detect early-stage steatosis. Consequently, patients may experience progressive liver pathology. The objective of this research is to ascertain the efficacy of serum glycan glycopatterns as a potential diagnostic biomarker, with a particular focus on the disease's early stages. We collected a total of 170 serum samples from volunteers with mild-NAFLD (Mild), severe-NAFLD (Severe), and non-NAFLD (None). Examination via lectin microarrays has uncovered pronounced disparities in serum glycopatterns identified by 19 distinct lectins. Following this, we employed four distinct machine learning algorithms to categorize the None, Mild, and Severe groups, drawing on the alterations observed in serum glycopatterns. The gradient boosting decision tree (GBDT) algorithm outperformed other models in diagnostic accuracy within the validation set, achieving an accuracy rate of 95% in differentiating the None group from the Mild group. Our research indicates that employing lectin microarrays to identify alterations in serum glycopatterns, when integrated with advanced machine learning algorithms, could constitute a promising approach for the diagnosis of NAFLD, with a special emphasis on its early detection.


Assuntos
Biomarcadores , Lectinas , Aprendizado de Máquina , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Biomarcadores/sangue , Lectinas/sangue , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Algoritmos , Polissacarídeos/sangue , Polissacarídeos/química , Glicoproteínas/sangue
12.
J Biol Chem ; 299(9): 105162, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37586586

RESUMO

Sphingomyelin synthase (SMS)-related protein (SMSr) is a phosphatidylethanolamine phospholipase C (PE-PLC) that is conserved and ubiquitous in mammals. However, its biological function is still not clear. We previously observed that SMS1 deficiency-mediated glucosylceramide accumulation caused nonalcoholic fatty liver diseases (NAFLD), including nonalcoholic steatohepatitis (NASH) and liver fibrosis. Here, first, we evaluated high-fat diet/fructose-induced NAFLD in Smsr KO and WT mice. Second, we evaluated whether SMSr deficiency can reverse SMS1 deficiency-mediated NAFLD, using Sms1/Sms2 double and Sms1/Sms2/Smsr triple KO mice. We found that SMSr/PE-PLC deficiency attenuated high-fat diet/fructose-induced fatty liver and NASH, and attenuated glucosylceramide accumulation-induced NASH, fibrosis, and tumor formation. Further, we found that SMSr/PE-PLC deficiency reduced the expression of many inflammatory cytokines and fibrosis-related factors, and PE supplementation in vitro or in vivo mimicked the condition of SMSr/PE-PLC deficiency. Furthermore, we demonstrated that SMSr/PE-PLC deficiency or PE supplementation effectively prevented membrane-bound ß-catenin transfer to the nucleus, thereby preventing tumor-related gene expression. Finally, we observed that patients with NASH had higher SMSr protein levels in the liver, lower plasma PE levels, and lower plasma PE/phosphatidylcholine ratios, and that human plasma PE levels are negatively associated with tumor necrosis factor-α and transforming growth factor ß1 levels. In conclusion, SMSr/PE-PLC deficiency causes PE accumulation, which can attenuate fatty liver, NASH, and fibrosis. These results suggest that SMSr/PE-PLC inhibition therapy may mitigate NAFLD.


Assuntos
Neoplasias , Hepatopatia Gordurosa não Alcoólica , Transferases (Outros Grupos de Fosfato Substituídos) , Animais , Humanos , Camundongos , Frutose/efeitos adversos , Glucosilceramidas/metabolismo , Fígado/metabolismo , Cirrose Hepática/patologia , Neoplasias/genética , Neoplasias/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fosfatidiletanolaminas/sangue , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Camundongos Knockout , Masculino , Feminino , Dieta Hiperlipídica/efeitos adversos
13.
J Biol Chem ; 299(3): 102937, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36690274

RESUMO

Defective autophagy and lipotoxicity are the hallmarks of nonalcoholic fatty liver disease. However, the precise molecular mechanism for the defective autophagy in lipotoxic conditions is not fully known. In the current study, we elucidated that activation of the mammalian target of rapamycin complex 1 (mTORC1)-G9a-H3K9me2 axis in fatty acid-induced lipotoxicity blocks autophagy by repressing key autophagy genes. The fatty acid-treated cells show mTORC1 activation, increased histone methyltransferase G9a levels, and suppressed autophagy as indicated by increased accumulation of the key autophagic cargo SQSTM1/p62 and decreased levels of autophagy-related proteins LC3II, Beclin1, and Atg7. Our chromatin immunoprecipitation analysis showed that decrease in autophagy was associated with increased levels of the G9a-mediated repressive H3K9me2 mark and decreased RNA polymerase II occupancy at the promoter regions of Beclin1 and Atg7 in fatty acid-treated cells. Inhibition of mTORC1 in fatty acid-treated cells decreased G9a-mediated H3K9me2 occupancy and increased polymerase II occupancy at Beclin1 and Atg7 promoters. Furthermore, mTORC1 inhibition increased the expression of Beclin1 and Atg7 in fatty acid-treated cells and decreased the accumulation of SQSTM1/p62. Interestingly, the pharmacological inhibition of G9a alone in fatty acid-treated cells decreased the H3K9me2 mark at Atg7 and Beclin1 promoters and restored the expression of Atg7 and Beclin1. Taken together, our findings have identified the mTORC1-G9a-H3K9me2 axis as a negative regulator of the autophagy pathway in hepatocellular lipotoxicity and suggest that the G9a-mediated epigenetic repression is mechanistically a key step during the repression of autophagy in lipotoxic conditions.


Assuntos
Autofagia , Ácidos Graxos , Histona Metiltransferases , Histonas , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Histonas/metabolismo , Ácidos Graxos/toxicidade , Autofagia/fisiologia , Epigênese Genética , Histona Metiltransferases/metabolismo , Hepatócitos/fisiologia , Células Hep G2 , Regulação da Expressão Gênica/efeitos dos fármacos , Palmitatos/toxicidade , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Regiões Promotoras Genéticas , Autofagossomos/genética , Autofagossomos/metabolismo , Humanos
14.
J Biol Chem ; 299(2): 102835, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36581203

RESUMO

Tetraspanins are transmembrane signaling and proinflammatory proteins. Prior work demonstrates that the tetraspanin, CD53/TSPAN25/MOX44, mediates B-cell development and lymphocyte migration to lymph nodes and is implicated in various inflammatory diseases. However, CD53 is also expressed in highly metabolic tissues, including adipose and liver; yet its function outside the lymphoid compartment is not defined. Here, we show that CD53 demarcates the nutritional and inflammatory status of hepatocytes. High-fat exposure and inflammatory stimuli induced CD53 in vivo in liver and isolated primary hepatocytes. In contrast, restricting hepatocyte glucose flux through hepatocyte glucose transporter 8 deletion or through trehalose treatment blocked CD53 induction in fat- and fructose-exposed contexts. Furthermore, germline CD53 deletion in vivo blocked Western diet-induced dyslipidemia and hepatic inflammatory transcriptomic activation. Surprisingly, metabolic protection in CD53 KO mice was more pronounced in the presence of an inciting inflammatory event. CD53 deletion attenuated tumor necrosis factor alpha-induced and fatty acid + lipopolysaccharide-induced cytokine gene expression and hepatocyte triglyceride accumulation in isolated murine hepatocytes. In vivo, CD53 deletion in nonalcoholic steatohepatitis diet-fed mice blocked peripheral adipose accumulation and adipose inflammation, insulin tolerance, and liver lipid accumulation. We then defined a stabilized and trehalase-resistant trehalose polymer that blocks hepatocyte CD53 expression in basal and over-fed contexts. The data suggest that CD53 integrates inflammatory and metabolic signals in response to hepatocyte nutritional status and that CD53 blockade may provide a means by which to attenuate pathophysiology in diseases that integrate overnutrition and inflammation, such as nonalcoholic steatohepatitis and type 2 diabetes.


Assuntos
Hepatócitos , Hepatopatia Gordurosa não Alcoólica , Tetraspanina 25 , Animais , Camundongos , Dieta Hiperlipídica , Hepatócitos/metabolismo , Inflamação/genética , Inflamação/metabolismo , Fígado/metabolismo , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/metabolismo , Tetraspanina 25/metabolismo , Tetraspaninas/genética , Tetraspaninas/metabolismo , Trealose/metabolismo
15.
Curr Issues Mol Biol ; 46(6): 5965-5983, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38921027

RESUMO

Hepatocellular carcinoma (HCC) represents a significant burden on global healthcare systems due to its considerable incidence and mortality rates. Recent trends indicate an increase in the worldwide incidence of metabolic dysfunction-associated steatotic liver disease (MASLD) and a shift in the etiology of HCC, with MASLD replacing the hepatitis B virus as the primary contributor to new cases of HCC. MASLD-related HCC exhibits distinct characteristics compared to viral HCC, including unique immune cell profiles resulting in an overall more immunosuppressive or exhausted tumor microenvironment. Furthermore, MASLD-related HCC is frequently identified in older age groups and among individuals with cardiometabolic comorbidities. Additionally, a greater percentage of MASLD-related HCC cases occur in noncirrhotic patients compared to those with viral etiologies, hindering early detection. However, the current clinical practice guidelines lack specific recommendations for the screening of HCC in MASLD patients. The evolving landscape of HCC management offers a spectrum of therapeutic options, ranging from surgical interventions and locoregional therapies to systemic treatments, for patients across various stages of the disease. Despite ongoing debates, the current evidence does not support differences in optimal treatment modalities based on etiology. In this study, we aimed to provide a comprehensive overview of the current literature on the trends, characteristics, clinical implications, and treatment modalities for MASLD-related HCC.

16.
Annu Rev Med ; 73: 529-544, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-34809436

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a major public health crisis affecting approximately 25% of the world's population. The spectrum of NAFLD ranges from bland steatosis to steatohepatitis with fibrosis; eventual development of cirrhosis in a subgroup of patients now represents the leading indication for liver transplant in women and in individuals older than 65. The development of noninvasive liver disease assessment tools has led to substantial progress in the diagnosis of NAFLD. Patients with NAFLD are at increased risk of cardiometabolic disease, which should therefore be an important part of the therapeutic approach. This review focuses on diagnosis and risk stratification of NAFLD across the full spectrum of disease, including important considerations in the approach to patients with cirrhosis.


Assuntos
Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica , Feminino , Fibrose , Humanos , Cirrose Hepática/diagnóstico , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/terapia
17.
Clin Gastroenterol Hepatol ; 22(1): 81-90.e4, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37406954

RESUMO

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD)-related fibrosis is heritable, but it is unclear how family history may be used to identify first-degree relatives with advanced fibrosis. We aimed to develop and validate a simple risk score to identify first-degree relatives of probands who have undergone assessment of liver fibrosis who are at higher risk of NAFLD with advanced fibrosis. METHODS: This prospective, cross-sectional, familial study consisted of a derivation cohort from San Diego, California, and a validation cohort from Helsinki, Finland. This study included consecutive adult probands (n = 242) with NAFLD and advanced fibrosis, NAFLD without advanced fibrosis, and non-NAFLD, with at least 1 of their first-degree relatives. All included probands and first-degree relatives underwent evaluation of liver fibrosis, the majority by magnetic resonance elastography. RESULTS: A total of 396 first-degree relatives (64% male) were included. The median age and body mass index were 47 years (interquartile range, 32-62 y) and 27.6 kg/m2 (interquartile range, 24.1-32.5 kg/m2), respectively. Age (1 point), type 2 diabetes (1 point), obesity (2 points), and proband with NAFLD and advanced fibrosis (2 points) were predictors of advanced fibrosis among first-degree relatives in the derivation cohort (n = 220) and formed the NAFLD Familial Risk Score. The area under the receiver operator characteristic curve of the NAFLD Familial Risk Score for detecting advanced fibrosis was 0.94 in the validation cohort (n = 176). The NAFLD Familial Risk Score outperformed the Fibrosis-4 index in the validation cohort (area under the receiver operator characteristic curve, 0.94 vs 0.70; P = .02). CONCLUSIONS: The NAFLD Familial Risk Score is a simple and accurate clinical tool to identify advanced fibrosis in first-degree relatives. These data may have implications for surveillance in NAFLD.


Assuntos
Diabetes Mellitus Tipo 2 , Hepatopatia Gordurosa não Alcoólica , Adulto , Humanos , Masculino , Feminino , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Transversais , Estudos Prospectivos , Fatores de Risco , Cirrose Hepática/diagnóstico , Cirrose Hepática/patologia , Predisposição Genética para Doença , Fígado/patologia , Biópsia
18.
Clin Gastroenterol Hepatol ; 22(2): 339-346.e5, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37678489

RESUMO

BACKGROUND & AIMS: Antimüllerian hormone (AMH) is a marker of ovarian reserve with emerging data linking lower levels to some metabolic and inflammatory diseases in women. Whether AMH levels influence nonalcoholic fatty liver disease (NAFLD) is unknown. METHODS: Leveraging the NASH Clinical Research Network we determined the association of AMH levels within 6 months of liver biopsy with presence and severity of histologic measures of NAFLD in premenopausal women. Outcomes included presence of nonalcoholic steatohepatitis (NASH), presence and severity of fibrosis, and NAFLD Activity Score and its components. Logistic and ordinal logistic regression models were adjusted for age, race/ethnicity, homeostatic model assessment for insulin resistance, body mass index, dyslipidemia, polycystic ovary syndrome, estrogen-progestin use, and menstrual cyclicity. RESULTS: Median cohort age was 35 years; 73% were white and 24% Hispanic. Thirty-three percent had diabetes, 81% had obesity, and 95% had dyslipidemia. On biopsy 71% had NASH, 68% had any fibrosis, and 15% had advanced fibrosis. On adjusted analysis (n = 205), higher AMH quartiles were inversely associated with NAFLD histology including prevalent NASH (adjusted odds ratio [AOR], 0.64; 95% confidence interval [CI], 0.41-1.00), NAFLD Activity Score ≥5 (AOR, 0.52; 95% CI, 0.35-0.77), Mallory hyaline (AOR, 0.54; 95% CI, 0.35-0.82), and higher fibrosis stage (AOR, 0.70; 95% CI, 0.51-0.98). The protective effects of AMH were more pronounced among women without polycystic ovary syndrome (n = 164), including lower odds of NASH (AOR, 0.53; 95% CI, 0.32-0.90) and any NASH fibrosis (AOR, 0.54; 95% CI, 0.32-0.93). CONCLUSIONS: AMH may reflect a unique biomarker of NASH in premenopausal women and findings suggest a novel link between reproductive aging and histologic severity of NAFLD in women.


Assuntos
Dislipidemias , Hepatopatia Gordurosa não Alcoólica , Reserva Ovariana , Síndrome do Ovário Policístico , Humanos , Feminino , Adulto , Hepatopatia Gordurosa não Alcoólica/complicações , Hormônio Antimülleriano , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/patologia , Cirrose Hepática/complicações , Dislipidemias/complicações , Fígado/patologia , Biópsia
19.
Clin Gastroenterol Hepatol ; 22(3): 581-590.e6, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37871842

RESUMO

BACKGROUND & AIMS: Hepatitis B surface antigen (HBsAg) seroclearance is the goal of functional cure for hepatitis B virus (HBV) infection. However, the impact of metabolic dysfunction-associated steatotic liver disease (MASLD) on this favorable outcome remains unclear. METHODS: Patients with chronic hepatitis B (CHB) were consecutively recruited. MASLD was defined by the newly proposed disease criteria. Cumulative incidences and associated factors of HBsAg seroclearance/seroconversion were compared between the MASLD and non-MASLD groups. RESULTS: From 2006 to 2021, 4084 treatment-naive hepatitis B e antigen (HBeAg)-negative CHB patients were included. At baseline, CHB patients with concurrent MASLD (n = 887) had significantly lower levels of HBsAg and HBV DNA than the non-MASLD group (n = 3197). During a median follow-up of 5.0 years, MASLD was associated with a higher likelihood of HBsAg seroclearance (adjusted hazard ratio [aHR], 1.43; 95% confidence interval [CI], 1.10-1.85; P = .007), and the accumulation of individual metabolic dysfunctions additively facilitated HBsAg seroclearance. In addition, a higher rate of HBsAg seroconversion was observed in patients with MASLD versus those without MASLD (aHR, 1.37; 95% CI, 1.00-1.86; P = .049). In sensitivity analysis, patients with intermittent MASLD had an intermediate probability of HBsAg seroclearance. After balancing clinical and virologic profiles by inverse probability of treatment weighting (IPTW), MASLD was still associated with a higher HBsAg seroclearance rate (IPTW-adjusted HR, 1.41; 95% CI, 1.09-1.84; P = .010). CONCLUSIONS: In untreated HBeAg-negative CHB patients, concurrent MASLD is associated with higher rates of HBsAg seroclearance and seroconversion. Metabolic dysfunctions have additive effects on the functional cure of CHB.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Antígenos de Superfície da Hepatite B , Antígenos E da Hepatite B , Soroconversão , Vírus da Hepatite B/genética , Hepatite B Crônica/tratamento farmacológico , DNA Viral/análise , Hepatite B/tratamento farmacológico , Antivirais/uso terapêutico
20.
Eur J Immunol ; 53(11): e2350474, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37489253

RESUMO

Kupffer cells (KCs) are liver-resident macrophages involved in hepatic inflammatory responses, including nonalcoholic fatty liver disease (NAFLD) development. However, the contribution of KC subsets to liver inflammation remains unclear. Here, using high-dimensional single-cell RNA sequencing, we characterized murine embryo-derived KCs and identified two KC populations with different gene expression profiles: KC-1 and KC-2. KC-1 expressed CD170, exhibiting immunoreactivity and immune-regulatory abilities, while KC-2 highly expressed lipid metabolism-associated genes. In a high-fat diet-induced NAFLD model, KC-1 cells differentiated into pro-inflammatory phenotypes and initiated more frequent communications with invariant natural killer T (iNKT) cells. In KC-1, interleukin (IL)-10 expression was unaffected by the high-fat diet but impaired by iNKT cell ablation and upregulated by iNKT cell adoptive transfer in vivo. Moreover, in a cellular co-culture system, primary hepatic iNKT cells promoted IL-10 expression in RAW264.7 and primary KC-1 cells. CD206 signal blocking in KC-1 or CD206 knockdown in RAW264.7 cells significantly reduced IL-10 expression. In conclusion, we identified two embryo-derived KC subpopulations with distinct transcriptional profiles. The CD206-mediated crosstalk between iNKT and KC-1 cells maintains IL-10 expression in KC-1 cells, affecting hepatic immune balance. Therefore, KC-based therapeutic strategies must consider cellular heterogeneity and the local immune microenvironment for enhanced specificity and efficiency.


Assuntos
Células T Matadoras Naturais , Hepatopatia Gordurosa não Alcoólica , Humanos , Animais , Camundongos , Células de Kupffer , Interleucina-10 , Fígado , Camundongos Endogâmicos C57BL
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