RESUMEN
Mallory-Denk bodies (MDBs) are hepatocellular cytoplasmic inclusions, which occur in certain chronic liver diseases, such as alcohol-related (ASH) and metabolic dysfunction-associated (MASH) steatohepatitis, copper toxicosis, some drug-induced liver disorders, chronic cholangiopathies, and liver tumors. Our study focused on the expression of the senescence markers p21WAF1/cip1 and p16INK4a in hepatocytes containing MDBs in steatohepatitis, chronic cholangiopathies with fibrosis or cirrhosis, Wilson's disease, and hepatocellular carcinomas. Cytoplasm and nuclei of MDB-containing hepatocytes as well as MDB inclusions, except those associated with carcinoma cells, were strongly p16-positive, p21-positive, as well as p21-negative nuclei in MDB-containing hepatocytes which were observed whereas MDBs were p21-negative. Expression of the senescence marker p16 suggests that MDB formation reflects an adaptive response to chronic stress resembling senescence with its consequences, i.e., expression of inflammation- and fibrosis-prone secretome. Thus, senescence can be regarded as "double-edged sword" since, on the one hand, it may be an attempt of cellular defense, but, on the other, also causes further and sustained damage by inducing inflammation and fibrosis related to the senescence-associated secretory phenotype and thus progression of chronic liver disease.
Asunto(s)
Senescencia Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Hepatocitos , Cuerpos de Mallory , Humanos , Hepatocitos/patología , Hepatocitos/metabolismo , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Cuerpos de Mallory/patología , Cuerpos de Mallory/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/metabolismo , Hígado/patología , Hígado/metabolismo , Biomarcadores/metabolismo , Biomarcadores/análisis , Hepatopatías/patología , Hepatopatías/metabolismo , Hepatopatías/etiologíaRESUMEN
LAMA2-related muscular dystrophy (LAMA2-MD) and SELENON(SEPN1)-related myopathy (SELENON-RM) are rare neuromuscular diseases caused by mutations in the LAMA2 and SELENON (SEPN1) gene, respectively. Systematic reviews on cardiac features in both neuromuscular diseases are lacking. This scoping review aims to elucidate the cardiac involvement in LAMA2-MD or SELENON-RM. Three electronic databases (PubMed, Embase and Cochrane) were searched. All studies, case reports and case series with information on cardiac features in LAMA2-MD or SELENON-RM patients were included. Study selection and data extraction were performed by two independent reviewers. 31 Articles on LAMA2-MD and 17 articles on SELENON-RM met the inclusion criteria, resulting in the inclusion of 131 LAMA2-MD and 192 SELENON-RM cases. In 41% of LAMA2-RM cases, a cardiac abnormality was present. Left ventricular systolic dysfunction and arrhythmia were most frequently described. In 15% of SELENON-RM cases, a cardiac abnormality was reported, of which pulmonary hypertension, including right ventricular dysfunction secondary to pulmonary failure, was most prevalent. We conclude that in LAMA2-MD primary left ventricular dysfunction and in SELENON-RM secondary right ventricular dysfunction are frequently reported. Optimal cardiorespiratory surveillance by screening of asymptomatic patients every two years with ECG, Holter and echocardiography is necessary for early detection and/or treatment of cardiac manifestations.
Asunto(s)
Enfermedades Musculares , Distrofias Musculares , Disfunción Ventricular Derecha , Humanos , Laminina/genética , Cuerpos de Mallory/patología , Distrofias Musculares/complicaciones , Distrofias Musculares/genética , Mutación , EscoliosisRESUMEN
Mallory-Denk bodies (MDBs) consist of intracellular aggregates of misfolded proteins in ballooned hepatocytes and serve as important markers of progression in certain liver diseases. Resident hepatic macrophage-mediated inflammation influences the development of chronic liver diseases and cancer. Here, the first systematic study of macrophages heterogeneity in mice was conducted to illustrate the pathogenesis of MDB formation using single-nucleus RNA sequencing (snRNA-seq). Furthermore, we provided transcriptional profiles of macrophages obtained from the fractionation of mouse liver tissues following chronic injury. We equally identified seven discrete macrophage subpopulations, each involved in specific cellular activated pathways such as basal metabolism, immune regulation, angiogenesis, and cell cycle regulation. Among these, a specific macrophage cluster (Cluster4), a subpopulation specifically expressing genes that regulate cell division and the cell cycle, was identified. Interestingly, we found that CCR2 was significantly induced in Cluster2, thereby inducing monocytes to migrate to macrophages to promote MDB pathogenesis. Thus, our study is the first to demonstrate the heterogeneity of macrophages associated with liver MDB formation in mice through single-cell resolution. This serves as the basis for further insights into the pathogenesis of liver MDB formation and molecular mechanisms of chronic liver disease progression.
Asunto(s)
Hepatopatías , Transcriptoma , Animales , Hepatocitos/metabolismo , Hígado/metabolismo , Hepatopatías/genética , Hepatopatías/patología , Macrófagos/metabolismo , Cuerpos de Mallory/metabolismo , RatonesRESUMEN
Autophagy is a degradation pathway for long-lived cytoplasmic proteins or damaged organelles and also for many aggregate-prone and disease-causing proteins. Endoplasmic reticulum (ER) stress and oxidative stress are associated with the pathophysiology of various liver diseases. These stresses induce the accumulation of abnormal proteins, Mallory-Denk body (MDB) formation and apoptosis in hepatocytes. A disaccharide trehalose had been reported to induce autophagy and decrease aggregate-prone proteins and cytotoxicity in neurodegenerative disease models. But the effects of trehalose in hepatocytes have not been fully understood. We examined the effect of trehalose on autophagy, ER stress and oxidative stress-mediated cytotoxicity and MDB formation in hepatocytes using mice model with 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) treatment for 3 months. We administered trehalose by intraperitoneal injection of water containing 10% trehalose (0.02 mg/g body weight) every other day for 3 months. Our results demonstrated that trehalose induced autophagy and reduced ER stress, oxidative stress, MDB formation and apoptosis in hepatocytes of DDC-fed mice by Western blotting and immunostaining analyses. Electron microscopy revealed that trehalose induced autolysosome formation, which located is close to the MDBs. Thus, our findings suggest that trehalose can become a therapeutic agent for oxidative stress-related liver diseases via activating autophagy.
Asunto(s)
Autofagia/efectos de los fármacos , Hepatopatías/prevención & control , Hígado/patología , Cuerpos de Mallory/efectos de los fármacos , Trehalosa/administración & dosificación , Administración Oral , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Modelos Animales de Enfermedad , Estrés del Retículo Endoplásmico/efectos de los fármacos , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Hígado/citología , Hígado/efectos de los fármacos , Hepatopatías/patología , Ratones , Estrés Oxidativo/efectos de los fármacos , Piridinas/administración & dosificación , Piridinas/toxicidadRESUMEN
Mallory-Denk Bodies (MDBs) are prevalent in a variety of liver diseases including alcoholic hepatitis (AH) and are formed in mice livers by feeding DDC. Long noncoding RNAs (lncRNAs) are considered as emerging new gene regulators, which participates in many functional activities through diverse mechanisms. We previously reported the mechanisms involved in the formation of liver MDBs in mouse model and in AH livers where MDBs had formed. To investigate the regulation of mRNAs expression and the probable role of lncRNAs in AH livers with MDBs, RNA-Seq analyses was further conducted to determine the mRNA and lncRNA expression profiles of the AH livers compared with the normal livers. It showed that different lncRNAs have different information contribution degrees by principal component analysis, and the integrated analysis of lncRNA-mRNA co-expression networks were linked to endocytosis, cell cycle, p53 signaling pathways in the human. Based on the co-expression networks, we identify 36 mRNAs that could be as potential biomarkers of alcoholic liver disease (ALD) and hepatocellular carcinoma (HCC). To our knowledge, this is the first report on the regulatory network of lncRNAs associated with liver MDB formation in human, and these results might offer new insights into the molecular mechanisms of liver MDB formation and the progression of AH to HCC.
Asunto(s)
Carcinoma Hepatocelular/genética , Hepatitis Alcohólica/genética , Neoplasias Hepáticas/genética , ARN Largo no Codificante/genética , Animales , Carcinoma Hepatocelular/patología , Ciclo Celular/genética , Modelos Animales de Enfermedad , Endocitosis/genética , Regulación de la Expresión Génica/genética , Redes Reguladoras de Genes/genética , Hepatitis Alcohólica/patología , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Hígado/metabolismo , Hígado/patología , Neoplasias Hepáticas/patología , Cuerpos de Mallory/genética , Cuerpos de Mallory/patología , Ratones , ARN Largo no Codificante/clasificación , ARN Mensajero/genética , Análisis de Secuencia de ARN , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/genéticaRESUMEN
BACKGROUND: Congenital muscular dystrophy (CMD) refers to hypotonia and delayed motor development that is manifested at or near the birth. Additional presentations have been observed in CMD syndromes. METHODS: Thorough clinical examinations were performed on two unrelated Iranian families with typical symptoms of CMD and uncommon features such as intellectual disability and nephrolithiasis. The genomic DNA of probands were subjected to whole exome sequencing. Following the detection of candidate variants with a bioinformatic pipeline, the familial co-segregation analysis was carried out using polymerase chain reaction-based Sanger sequencing. RESULTS: We identified a missense homozygous variant in the fukutin-related protein (FKRP) gene (c.968G>A, p.Arg323His) related to CMD-dystroglycanopathy type B5 (MDDGB5) and a frameshift homozygous variant in the selenoprotein N (SELENON) gene (c.1446delC, p.Asn483Thrfs*11) associated with congenital rigid-spine muscular dystrophy 1 (RSMD1), which were completely segregated with the phenotypes in the families. These variants were not found in either the 1000 Genomes Project or the Exome Aggregation Consortium. The present study provides the first report of these homozygous sequence variants in Iran. Moreover, our study was the first observation of nephrolithiasis in FKRP-related dystroglycanopathy and intellectual disability in SELENON-related myopathies. Based on in silico studies and molecular docking, these variations induced pathogenic effects on the proteins. CONCLUSIONS: Our findings extend the genetic database of Iranian patients with CMD and, in general, the phenotypical spectrum of syndromic CMD. It is recommended to consider these variants for a more accurate clinical interpretation, prenatal diagnosis and genetic counseling in families with a history of CMD, especially in those combined with cognitive impairments or renal dysfunctions.
Asunto(s)
Homocigoto , Cuerpos de Mallory/patología , Proteínas Musculares/genética , Distrofias Musculares/patología , Mutación , Pentosiltransferasa/genética , Fenotipo , Escoliosis/patología , Selenoproteínas/genética , Niño , Femenino , Humanos , Irán , Masculino , Cuerpos de Mallory/genética , Simulación del Acoplamiento Molecular , Proteínas Musculares/química , Distrofias Musculares/genética , Linaje , Pentosiltransferasa/química , Pronóstico , Escoliosis/genética , Selenoproteínas/químicaRESUMEN
Keratin 8 (K8) and keratin 18 (K18) are the intermediate filament proteins whose phosphorylation/transamidation associate with their aggregation in Mallory-Denk bodies found in patients with various liver diseases. However, the functions of other post-translational modifications in keratins related to liver diseases have not been fully elucidated. Here, using a site-specific mutation assay combined with nano-liquid chromatography-tandem mass spectrometry, we identified K8-Lys108 and K18-Lys187/426 as acetylation sites, and K8-Arg47 and K18-Arg55 as methylation sites. Keratin mutation (Arg-to-Lys/Ala) at the methylation sites, but not the acetylation sites, led to decreased stability of the keratin protein. We compared keratin acetylation/methylation in liver disease-associated keratin variants. The acetylation of K8 variants increased or decreased to various extents, whereas the methylation of K18-del65-72 and K18-I150V variants increased. Notably, the highly acetylated/methylated K18-I150V variant was less soluble and exhibited unusually prolonged protein stability, which suggests that additional acetylation of highly methylated keratins has a synergistic effect on prolonged stability. Therefore, the different levels of acetylation/methylation of the liver disease-associated variants regulate keratin protein stability. These findings extend our understanding of how disease-associated mutations in keratins modulate keratin acetylation and methylation, which may contribute to disease pathogenesis.-Jang, K.-H., Yoon, H.-N., Lee, J., Yi, H., Park, S.-Y., Lee, S.-Y., Lim, Y., Lee, H.-J., Cho, J.-W., Paik, Y.-K., Hancock, W. S., Ku, N.-O. Liver disease-associated keratin 8 and 18 mutations modulate keratin acetylation and methylation.
Asunto(s)
Queratina-18/genética , Queratina-18/metabolismo , Queratina-8/genética , Queratina-8/metabolismo , Hepatopatías/genética , Hepatopatías/metabolismo , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Acetilación , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Sitios de Unión/genética , Línea Celular , Cricetinae , Células HT29 , Humanos , Queratina-18/química , Queratina-8/química , Cuerpos de Mallory/metabolismo , Metilación , Proteínas Mutantes/química , Mutación Missense , Procesamiento Proteico-Postraduccional , Estabilidad Proteica , Espectrometría de Masas en TándemRESUMEN
BACKGROUND: Muscular dystrophies are a clinically and genetically heterogeneous group of disorders characterized by variable degrees of progressive muscle degeneration and weakness. There is a wide variability in the age of onset, symptoms and rate of progression in subtypes of these disorders. Herein, we present the results of our study conducted to identify the pathogenic genetic variation involved in our patient affected by rigid spine muscular dystrophy. CASE PRESENTATION: A 14-year-old boy, product of a first-cousin marriage, was enrolled in our study with failure to thrive, fatigue, muscular dystrophy, generalized muscular atrophy, kyphoscoliosis, and flexion contracture of the knees and elbows. Whole-exome sequencing (WES) was carried out on the DNA of the patient to investigate all coding regions and uncovered a novel, homozygous missense mutation in SEPN1 gene (c. 1379 C > T, p.Ser460Phe). This mutation has not been reported before in different public variant databases and also our database (BayanGene), so it is classified as a variation of unknown significance (VUS). Subsequently, it was confirmed that the novel variation was homozygous in our patient and heterozygous in his parents. Different bioinformatics tools showed the damaging effects of the variant on protein. Multiple sequence alignment using BLASTP on ExPASy and WebLogo, revealed the conservation of the mutated residue. CONCLUSION: We reported a novel homozygous mutation in SEPN1 gene that expands our understanding of rigid spine muscular dystrophy. Although bioinformatics analyses of results were in favor of the pathogenicity of the mutation, functional studies are needed to establish the pathogenicity of the variant.
Asunto(s)
Predisposición Genética a la Enfermedad , Cuerpos de Mallory/patología , Proteínas Musculares/genética , Distrofias Musculares/genética , Mutación , Escoliosis/genética , Selenoproteínas/genética , Adolescente , Secuencia de Aminoácidos , Análisis Mutacional de ADN , Pruebas Genéticas , Variación Genética , Secuenciación de Nucleótidos de Alto Rendimiento , Homocigoto , Humanos , Irán , Masculino , Cuerpos de Mallory/genética , Atrofia Muscular , Distrofias Musculares/fisiopatología , Mutación Missense , Linaje , Escoliosis/fisiopatología , Alineación de SecuenciaRESUMEN
Rigid spine syndrome is a rare myopathy in children and has a poor prognosis because of its lack of treatment and eventual ventilatory failure. We report the case of a 10-year-old child with RSS and ventilatory disorders. We provided care to the child using bilevel positive airway pressure (BiPAP) non-invasive mechanical ventilation and continuous monitoring of transcutaneous carbon dioxide pressure. A 10-year-old Han Chinese girl presented (6 April 6 2016) to the Shanghai Children's Medical Center with ventilatory disorders, including hypoxia and hypercapnia. Transcutaneous oxygen saturation with mask oxygen inspiration was 90%. BiPAP non-invasive ventilator-assisted ventilation was continuously used. Through continuous non-invasive ventilation and carbon dioxide monitoring, the symptoms of dyspnea in this child were effectively controlled and improved. She was discharged on April 19 with instructions to continue using BiPAP at home and transcutaneous oxygen saturation was maintained at 94% to 98%. This case highlights that nursing of patients with rigid spine syndrome and ventilatory disorders should focus on evaluating the effect of non-invasive mechanical ventilation, prevention of complications, and continuous nursing after discharge. Additionally, continuous monitoring of transcutaneous carbon dioxide pressure is feasible for evaluating the effect of BiPAP.
Asunto(s)
Cuerpos de Mallory/patología , Distrofias Musculares/complicaciones , Respiración con Presión Positiva , Respiración Artificial , Insuficiencia Respiratoria/etiología , Escoliosis/complicaciones , Dióxido de Carbono/análisis , Niño , Femenino , Humanos , Pronóstico , Insuficiencia Respiratoria/enfermería , Insuficiencia Respiratoria/patología , Insuficiencia Respiratoria/terapiaRESUMEN
Chronic intoxication of mice with the porphyrinogenic compound 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) leads to morphological and metabolic changes closely resembling steatohepatitis, a severe form of metabolic liver disease in humans. Since human steatohepatitis (both the alcoholic and non-alcoholic type) is characterized by reduced expression of PPARα and disturbed lipid metabolism we investigated the role of this ligand-activated receptor in the development of DDC-induced liver injury. Acute DDC-intoxication was accompanied by early significant downregulation of Pparα mRNA expression along with PPARα-controlled stress-response and lipid metabolism genes that persisted in the chronic stage. Administration of the specific PPARα agonist fenofibrate together with DDC prevented the downregulation of PPARα-associated genes and also improved the stress response of Nrf2-dependent redox-regulating genes. Moreover, oxidative stress and inflammation were strongly reduced by DDC/fenofibrate co-treatment. In addition, fenofibrate prevented the disruption of hepatocyte intermediate filament cytoskeleton and the formation of Mallory-Denk bodies at late stages of DDC intoxication. Our findings show that, like in human steatohepatitis, PPARα is downregulated in the DDC model of steatohepatitis-like hepatocellular damage. Its downregulation and the pathomorphologic features of steatohepatitis are prevented by co-administration of fenofibrate.
Asunto(s)
Regulación hacia Abajo/efectos de los fármacos , Hígado Graso , Fenofibrato/farmacología , Cuerpos de Mallory/metabolismo , PPAR alfa , Agregado de Proteínas/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Hígado Graso/inducido químicamente , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/prevención & control , Humanos , Masculino , Cuerpos de Mallory/patología , Ratones , Estrés Oxidativo/efectos de los fármacos , PPAR alfa/agonistas , PPAR alfa/biosíntesis , Piridinas/toxicidadRESUMEN
OBJECTIVE: To describe a large series of BIN1 patients, in which a novel founder mutation in the Roma population of southern Spain has been identified. METHODS: Patients diagnosed with centronuclear myopathy (CNM) at 5 major reference centers for neuromuscular disease in Spain (n = 53) were screened for BIN1 mutations. Clinical, histologic, radiologic, and genetic features were analyzed. RESULTS: Eighteen patients from 13 families carried the p.Arg234Cys variant; 16 of them were homozygous for it and 2 had compound heterozygous p.Arg234Cys/p.Arg145Cys mutations. Both BIN1 variants have only been identified in Roma, causing 100% of CNM in this ethnic group in our cohort. The haplotype analysis confirmed all families are related. In addition to clinical features typical of CNM, such as proximal limb weakness and ophthalmoplegia, most patients in our cohort presented with prominent axial weakness, often associated with rigid spine. Severe fat replacement of paravertebral muscles was demonstrated by muscle imaging. This phenotype seems to be specific to the p.Arg234Cys mutation, not reported in other BIN1 mutations. Extreme clinical variability was observed in the 2 compound heterozygous patients for the p.Arg234Cys/p.Arg145Cys mutations, from a congenital onset with catastrophic outcome to a late-onset disease. Screening of European Roma controls (n = 758) for the p.Arg234Cys variant identified a carrier frequency of 3.5% among the Spanish Roma. CONCLUSION: We have identified a BIN1 founder Roma mutation associated with a highly specific phenotype, which is, from the present cohort, the main cause of CNM in Spain.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Efecto Fundador , Cuerpos de Mallory/patología , Distrofias Musculares/genética , Mutación/genética , Miopatías Estructurales Congénitas/genética , Proteínas Nucleares/genética , Romaní/genética , Escoliosis/genética , Proteínas Supresoras de Tumor/genética , Adolescente , Adulto , Niño , Estudios de Cohortes , Humanos , Cuerpos de Mallory/genética , Persona de Mediana Edad , Distrofias Musculares/diagnóstico por imagen , Distrofias Musculares/etnología , Miopatías Estructurales Congénitas/diagnóstico por imagen , Miopatías Estructurales Congénitas/etnología , Fenotipo , Estudios Prospectivos , Estudios Retrospectivos , Romaní/etnología , Escoliosis/diagnóstico por imagen , Escoliosis/etnología , España/etnología , Adulto JovenAsunto(s)
Cuerpos de Mallory/patología , Proteínas Musculares/genética , Distrofias Musculares/diagnóstico , Distrofias Musculares/genética , Mutagénesis Insercional , Escoliosis/diagnóstico , Escoliosis/genética , Selenoproteínas/genética , Niño , Humanos , Masculino , Cuerpos de Mallory/genética , Distrofias Musculares/fisiopatología , Escoliosis/fisiopatología , Análisis de Secuencia de ADN , Columna Vertebral/fisiopatologíaRESUMEN
OBJECTIVES: Inherited myopathies are major causes of muscle atrophy and are often characterized by rigid spine syndrome, a clinical feature designating patients with early spinal contractures. We aim to present a decision algorithm based on muscular whole body magnetic resonance imaging (mWB-MRI) as a unique tool to orientate the diagnosis of each inherited myopathy long before the genetically confirmed diagnosis. METHODS: This multicentre retrospective study enrolled 79 patients from referral centres in France, Brazil and Chile. The patients underwent 1.5-T or 3-T mWB-MRI. The protocol comprised STIR and T1 sequences in axial and coronal planes, from head to toe. All images were analyzed manually by multiple raters. Fatty muscle replacement was evaluated on mWB-MRI using both the Mercuri scale and statistical comparison based on the percentage of affected muscle. RESULTS: Between February 2005 and December 2015, 76 patients with genetically confirmed inherited myopathy were included. They were affected by Pompe disease or harbored mutations in RYR1, Collagen VI, LMNA, SEPN1, LAMA2 and MYH7 genes. Each myopathy had a specific pattern of affected muscles recognizable on mWB-MRI. This allowed us to create a novel decision algorithm for patients with rigid spine syndrome by segregating these signs. This algorithm was validated by five external evaluators on a cohort of seven patients with a diagnostic accuracy of 94.3% compared with the genetic diagnosis. CONCLUSION: We provide a novel decision algorithm based on muscle fat replacement graded on mWB-MRI that allows diagnosis and differentiation of inherited myopathies presenting with spinal rigidity. KEY POINTS: ⢠Inherited myopathies are rare, diagnosis is challenging and genetic tests require specialized centres and often take years. ⢠Inherited myopathies are often characterized by spinal rigidity. ⢠Whole body magnetic resonance imaging is a unique tool to orientate the diagnosis of each inherited myopathy presenting with spinal rigidity. ⢠Each inherited myopathy in this study has a specific pattern of affected muscles that orientate diagnosis. ⢠A novel MRI-based algorithm, usable by every radiologist, can help the early diagnosis of these myopathies.
Asunto(s)
Algoritmos , Imagen por Resonancia Magnética/métodos , Cuerpos de Mallory/patología , Rigidez Muscular/diagnóstico , Músculo Esquelético/patología , Distrofias Musculares/diagnóstico , Escoliosis/diagnóstico , Imagen de Cuerpo Entero/métodos , Adolescente , Adulto , Anciano , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rigidez Muscular/etiología , Rigidez Muscular/fisiopatología , Músculo Esquelético/fisiopatología , Distrofias Musculares/fisiopatología , Estudios Retrospectivos , Escoliosis/fisiopatología , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
BACKGROUND & AIMS: Heat shock protein (Hsp) 72 is a molecular chaperone that has broad cytoprotective functions and is upregulated in response to stress. To determine its hepatic functions, we studied its expression in human liver disorders and its biological significance in newly generated transgenic animals. METHODS: Double transgenic mice overexpressing Hsp72 (gene Hspa1a) under the control of a tissue-specific tetracycline-inducible system (Hsp72-LAP mice) were produced. Acute liver injury was induced by a single injection of acetaminophen (APAP). Feeding with either a methionine choline-deficient (MCD; 8â¯weeks) or a 3,5-diethoxycarbonyl-1,4-dihydrocollidine-supplemented diet (DDC; 12â¯weeks) was used to induce lipotoxic injury and Mallory-Denk body (MDB) formation, respectively. Primary hepatocytes were treated with palmitic acid. RESULTS: Patients with non-alcoholic steatohepatitis and chronic hepatitis C infection displayed elevated HSP72 levels. These levels increased with the extent of hepatic inflammation and HSP72 expression was induced after treatment with either interleukin (IL)-1ß or IL-6. Hsp72-LAP mice exhibited robust, hepatocyte-specific Hsp72 overexpression. Primary hepatocytes from these animals were more resistant to isolation-induced stress and Hsp72-LAP mice displayed lower levels of hepatic injury in vivo. Mice overexpressing Hsp72 had fewer APAP protein adducts and were protected from oxidative stress and APAP-/MCD-induced cell death. Hsp72-LAP mice and/or hepatocytes displayed significantly attenuated Jnk activation. Overexpression of Hsp72 did not affect steatosis or the extent of MDB formation. CONCLUSIONS: Our results demonstrate that HSP72 induction occurs in human liver disease, thus, HSP72 represents an attractive therapeutic target owing to its broad hepatoprotective functions. LAY SUMMARY: HSP72 constitutes a stress-inducible, protective protein. Our data demonstrate that it is upregulated in patients with chronic hepatitis C and non-alcoholic steatohepatitis. Moreover, Hsp72-overexpressing mice are protected from various forms of liver stress.
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Enfermedad Hepática Inducida por Sustancias y Drogas/prevención & control , Proteínas del Choque Térmico HSP72/metabolismo , Reacción de Fase Aguda/metabolismo , Reacción de Fase Aguda/patología , Animales , Muerte Celular , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Modelos Animales de Enfermedad , Femenino , Proteínas del Choque Térmico HSP72/genética , Hepatitis C Crónica/metabolismo , Hepatitis C Crónica/patología , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Sistema de Señalización de MAP Quinasas , Masculino , Cuerpos de Mallory/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Estrés Oxidativo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Regulación hacia ArribaRESUMEN
INTRODUCTION: Bcl-2-associated athanogene-3 (BAG3) mutations have been described in rare cases of rapidly progressive myofibrillar myopathies. Symptoms begin in the first decade with axial involvement and contractures and are associated with cardiac and respiratory impairment in the second decade. Axonal neuropathy has been documented but usually not as a key clinical feature. METHODS: We report a 24-year-old woman with severe rigid spine syndrome and sensory-motor neuropathy resembling Charcot-Marie-Tooth disease (CMT). RESULTS: Muscle MRI showed severe fat infiltration without any specific pattern. Deltoid muscle biopsy showed neurogenic changes and discrete myofibrillar abnormalities. Electrocardiogram and transthoracic echocardiography results were normal. Genetic analysis of a panel of 45 CMT genes showed no mutation. BAG3 gene screening identified the previously reported c.626C>T, pPro209Leu, mutation. DISCUSSION: This case indicates that rigid spine syndrome and sensory-motor axonal neuropathy are key clinical features of BAG3 mutations that should be considered even without cardiac involvement. Muscle Nerve, 57: 330-334, 2018.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Reguladoras de la Apoptosis/genética , Enfermedad de Charcot-Marie-Tooth/genética , Neuropatía Hereditaria Motora y Sensorial/genética , Cuerpos de Mallory/patología , Distrofias Musculares/genética , Escoliosis/genética , Biopsia , Enfermedad de Charcot-Marie-Tooth/complicaciones , Enfermedad de Charcot-Marie-Tooth/diagnóstico por imagen , Electrodiagnóstico , Femenino , Cardiopatías/complicaciones , Neuropatía Hereditaria Motora y Sensorial/complicaciones , Neuropatía Hereditaria Motora y Sensorial/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Cuerpos de Mallory/genética , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Distrofias Musculares/complicaciones , Distrofias Musculares/diagnóstico por imagen , Mutación/genética , Escoliosis/complicaciones , Escoliosis/diagnóstico por imagen , Adulto JovenRESUMEN
Several research strategies have been used to study the pathogenesis of alcoholic hepatitis (AH). These strategies have shown that various signaling pathways are the target of alcohol in liver cells. However, few have provided specific mechanisms associated with Mallory-Denk Bodies (MDBs) formed in Balloon cells in AH. The formation of MDBs in these hepatocytes is an indication that the mechanisms of protein quality control have failed. The MDB is the result of aggregation and accumulation of proteins in the cytoplasm of balloon degenerated liver cells. To understand the mechanisms that failed to degrade and remove proteins in the hepatocyte from patients suffering from alcoholic hepatitis, we investigated the pathways that showed significant up regulation in the AH liver biopsies compared to normal control livers (Liu et al., 2015). Analysis of genomic profiles of AH liver biopsies and control livers by RNA-seq revealed different pathways that were up regulated significantly. In this study, the focus was on Tec kinase signaling pathways and the genes that significantly interrupt this pathway. Quantitative PCR and immunofluorescence staining results, indicated that several genes and proteins are significantly over expressed in the livers of AH patients that affect the Tec kinase signaling to PI3K which leads to activation of Akt and its downstream effectors.
Asunto(s)
Biomarcadores/metabolismo , Hepatitis Alcohólica/patología , Hepatocitos/patología , Hígado/patología , Cuerpos de Mallory/patología , Proteínas Tirosina Quinasas/metabolismo , Transducción de Señal , Estudios de Casos y Controles , Perfilación de la Expresión Génica , Hepatitis Alcohólica/metabolismo , Hepatocitos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Hígado/metabolismo , Cuerpos de Mallory/metabolismo , Proteínas Tirosina Quinasas/genéticaRESUMEN
Intermediate filament proteins (IFs), such as cytoplasmic keratins in epithelial cells and vimentin in mesenchymal cells and the nuclear lamins, make up one of the three major cytoskeletal protein families. Whether in digestive organs or other tissues, IFs share several unique features including stress-inducible overexpression, abundance, cell-selective and differentiation state expression, and association with >80 human diseases when mutated. Whereas most IF mutations cause disease, mutations in simple epithelial keratins 8, 18, or 19 or in lamin A/C predispose to liver disease with or without other tissue manifestations. Keratins serve major functions including protection from apoptosis, providing cellular and subcellular mechanical integrity, protein targeting to subcellular compartments, and scaffolding and regulation of cell-signaling processes. Keratins are essential for Mallory-Denk body aggregate formation that occurs in association with several liver diseases, whereas an alternate type of keratin and lamin aggregation occurs upon liver involvement in porphyria. IF-associated diseases have no known directed therapy, but high-throughput drug screening to identify potential therapies is an appealing ongoing approach. Despite the extensive current knowledge base, much remains to be discovered regarding IF physiology and pathophysiology in digestive and nondigestive organs.
Asunto(s)
Enfermedades del Sistema Digestivo/metabolismo , Sistema Digestivo/metabolismo , Proteínas de Filamentos Intermediarios/metabolismo , Filamentos Intermedios/metabolismo , Animales , Sistema Digestivo/patología , Sistema Digestivo/fisiopatología , Enfermedades del Sistema Digestivo/genética , Enfermedades del Sistema Digestivo/patología , Enfermedades del Sistema Digestivo/fisiopatología , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Humanos , Proteínas de Filamentos Intermediarios/genética , Filamentos Intermedios/genética , Filamentos Intermedios/patología , Cuerpos de Mallory/metabolismo , Cuerpos de Mallory/patología , Mutación , Fenotipo , Polimorfismo GenéticoRESUMEN
In this study, liver biopsy sections fixed in formalin and embedded in paraffin (FFPE) from patients with alcoholic hepatitis (AH) were used. The results showed that the expression of the SYK protein was up regulated by RNA-seq and real time PCR analyses in the alcoholic hepatitis patients compared to controls. The results were supported by using the IHC fluorescent antibody staining intensity morphometric quantitation. Morphometric quantification of fluorescent intensity measurement showed a two fold increase in SYK protein in the cytoplasm of the cells forming MDBs compared to surrounding normal hepatocytes. The expression of AKT1 was also analyzed. AKT1 is a serine/threonine-specific protein kinase that plays a key role in multiple cellular processes such as glucose metabolism, apoptosis, cell proliferation, transcription and cell migration. The AKT protein was also increased in hepatocyte balloon cells forming MDBs. This observation demonstrates the role of SYK and its subsequent effect on the internal signaling pathways such as PI3K/AKT as well as p70S6K, as a potential multifunctional target in protein quality control mechanisms of hepatocytes when ER stress is activated.