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Ferroptosis is a nonapoptotic form of cell death and differs considerably from the well-known forms of cell death in terms of cell morphology, genetics, and biochemistry. The three primary pathways for cell ferroptosis are system Xc-/glutathione peroxidase 4 (GPX4), lipid metabolism, and ferric metabolism. Since the discovery of ferroptosis, mounting evidence has revealed its critical regulatory role in several diseases, especially as a novel potential target for cancer therapy, thereby attracting increasing attention in the fields of tumor biology and anti-tumor therapy. Accordingly, broad prospects exist for identifying ferroptosis as a potential therapeutic target. In this review, we aimed to systematically summarize the activation and defense mechanisms of ferroptosis, highlight the therapeutic targets, and discuss the design of nanomedicines for ferroptosis regulation. In addition, we opted to present the advantages and disadvantages of current ferroptosis research and provide an optimistic vision of future directions in related fields. Overall, we aim to provide new ideas for further ferroptosis research and inspire new strategies for disease diagnosis and treatment.
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Photodynamic therapy (PDT) is a temporally and spatially precisely controllable, noninvasive, and potentially highly efficient method of phototherapy. The three components of PDT primarily include photosensitizers, oxygen, and light. PDT employs specific wavelengths of light to active photosensitizers at the tumor site, generating reactive oxygen species that are fatal to tumor cells. Nevertheless, traditional photosensitizers have disadvantages such as poor water solubility, severe oxygen-dependency, and low targetability, and the light is difficult to penetrate the deep tumor tissue, which remains the toughest task in the application of PDT in the clinic. Here, we systematically summarize the development and the molecular mechanisms of photosensitizers, and the challenges of PDT in tumor management, highlighting the advantages of nanocarriers-based PDT against cancer. The development of third generation photosensitizers has opened up new horizons in PDT, and the cooperation between nanocarriers and PDT has attained satisfactory achievements. Finally, the clinical studies of PDT are discussed. Overall, we present an overview and our perspective of PDT in the field of tumor management, and we believe this work will provide a new insight into tumor-based PDT.
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The development of hyperuricemia (HUA) and gout is associated with dysbiosis of the gut microbiota. Quercetin can reduce serum uric acid levels and thus alleviate HUA by modulating the gut microbiota. However, the detailed mechanisms involved in this process are not fully understood. Here, we showed that quercetin significantly reduced the serum uric acid level in a chicken HUA model by altering the chicken cecal microbiota structure and function and increasing the abundance of Lactobacillus aviarius. An L. aviarius strain, CML180, was isolated from the quercetin-treated chicken gut microbiota. Strain characterization indicated that quercetin promoted the growth of L. aviarius CML180 and increased its adhesion, hydrophobicity, and co-aggregation abilities. Gavage of live L. aviarius CML180 to a mouse model of HUA-established by adenosine and potassium oxonate-reduced the serum uric acid level and alleviated HUA. The ability of L. aviarius CML180 to decrease the level of uric acid was due to its degradation of purine nucleosides, which are the precursors for uric acid production. A nucleoside hydrolase gene, nhy69, was identified from the genome of L. aviarius CML180, and the resulting protein, Nhy69, exhibited strong purine nucleoside-hydrolyzing activity at mesophilic temperature and neutral pH conditions. These findings provide mechanistic insights into the potential of quercetin to treat HUA or gout diseases via a specific gut microbe.
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The single-crystal Ni-rich Li(NixCoyMn1-x-y)O2 cathode (NCM) demonstrates better cycle performance, enhanced tap density and improved mechanical structure stability, compared with polycrystalline NCM.However, limited Li+ transports, (003) plane slips and microcracks in large single particles hinder rate capability and cycle performance. To overcome these shortcomings,single-crystal NCM cathodes have been modified by nanosized tetragonal BaTiO3. Due to the dielectric properties, BaTiO3 particles induce electric field concentration at the BaTiO3-NCM-electrolyte interface. Thus, a large amount of lithium vacancies can be formed, providing sufficient sites for the hopping diffusion of lithium ions, thereby significantly enhancing the diffusion coefficient of Li+. Moreover, the redistribution of charges can inhibit the formation and accumulation of cathode-electrolyte-interface. Owing to the synergetic effect of BaTiO3, the BT-modified single-crystal NCM with the optimized loading shows a remarkable initial discharge capacity of 138.5 mAh g-1 and maintains 53.8% of its initial discharge capacity after 100 cycles under 5C at 4.5 V cut-off voltage. Overall, the proposed dielectric cathode-electrolyte-interface strategy can enhance Li+ ion transport and stabilize the interface structure, leading to improved rate performance. Meanwhile, the diffusion-induced state of charge gradient can also be inhibited, resulting in high structure stability of single-crystal NCMs under high rate and cut-off voltage cycling.
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Purpose: The study aimed to investigate the potential protective role of anthocyanin from Lycium ruthenicum Murr. in the Qaidam Basin against ultraviolet B (UVB)-induced apoptosis of human skin fibroblasts (HSFs). Methods: HSFs cultured in vitro were randomly divided into a control group, UVB group, and anthocyanin groups (0.1, 0.5, and 1.0 mg/mL). HSFs in the UVB and anthocyanin groups were exposed to 30 mJ/cm2 UVB to establish a photoaging model. Then, apoptosis rate, tumor necrosis factor-α (TNF-α), cysteinyl aspartate specific proteinase-3 (caspase-3), cysteinyl aspartate specific proteinase-7 (caspase-7), and survivin expression were evaluated. Results: UVB irradiation can increase the apoptosis rate of HSFs and expression of TNF-α, caspase-7, and survivin. Anthocyanin pretreatment (0.1, 0.5, and 1.0 mg/mL) decreased UVB-induced apoptosis rate and TNF-α and caspase-7 expression and increased survivin expression. Compared with the control group, the apoptosis rate and expression of TNF-α, caspase-7, and survivin of anthocyanin groups in UVB-irradiated HSFs were high. Among the three doses of anthocyanin (0.1, 0.5, and 1.0 mg/mL) groups, the apoptosis rate and TNF-α expression of anthocyanin at 1.0 mg/mL were the lowest. There was no significant change in caspase-3 expression in each group. Conclusion: Anthocyanin from Lycium ruthenicum Murr. in the Qaidam Basin could alleviate UVB-induced apoptosis by regulating the death receptor pathway.
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Progressive familial intrahepatic cholestasis type 1 (PFIC1) results from biallelic pathogenic variants in ATP8B1. This study sought second pathogenic variants in ATP8B1 by whole-genome sequencing (WGS) in four unrelated low γ-glutamyl transpeptidase cholestasis patients in whom clinical suspicion of PFIC1 was high and gene-panel or Sanger sequencing had identified only one pathogenic variant in ATP8B1. Sanger sequencing confirmed WGS findings and determined the origin of each variant. Novel nonrecurrent structural variants in three patients (patient 1 to patient 3) were identified in trans: g.55396652_55403080del (6427-bp deletion), g.55335906_55346620dup (10,715-bp duplication), and g.55362063_55364293dup (2231-bp duplication). One synonymous variant in patient 4 was recognized in trans (c.1029G>A, p. Thr343Thr) and demonstrated as deleterious. In conclusion, WGS improves genetic diagnostic yield in PFIC1. These findings expand the gene-variant spectrum associated with familiar intrahepatic cholestasis 1 (FIC1) disease and for the first time report tandem duplication in ATP8B1 associated with cholestasis.
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Adenosina Trifosfatases/genética , Colestase Intra-Hepática/genética , Deleção de Genes , Duplicação Gênica , Sequenciamento Completo do Genoma/métodos , Ácidos e Sais Biliares/sangue , Criança , Pré-Escolar , Colestase Intra-Hepática/sangue , Variações do Número de Cópias de DNA , Feminino , Testes Genéticos/métodos , Humanos , Mutação INDEL , Lactente , Recém-Nascido , Masculino , Fenótipo , Polimorfismo de Nucleotídeo Único , Sequências de Repetição em Tandem/genética , gama-Glutamiltransferase/sangueRESUMO
BACKGROUND: For many children with intrahepatic cholestasis and high-serum gamma-glutamyl transferase (GGT) activity, a genetic aetiology of hepatobiliary disease remains undefined. We sought to identify novel genes mutated in children with idiopathic high-GGT intrahepatic cholestasis, with clinical, histopathological and functional correlations. METHODS: We assembled a cohort of 25 children with undiagnosed high-GGT cholestasis and without clinical features of biliary-tract infection or radiological features of choledochal malformation, sclerosing cholangitis or cholelithiasis. Mutations were identified through whole-exome sequencing and targeted Sanger sequencing. We reviewed histopathological findings and assessed phenotypical effects of ZFYVE19 deficiency in cultured cells by immunofluorescence microscopy. RESULTS: Nine Han Chinese children harboured biallelic, predictedly complete loss-of-function pathogenic mutations in ZFYVE19 (c.314C>G, p.S105X; c.379C>T, p.Q127X; c.514C>T, p.R172X; c.547C>T, p.R183X; c.226A>G, p.M76V). All had portal hypertension and, at liver biopsy, histopathological features of the ductal plate malformation (DPM)/congenital hepatic fibrosis (CHF). Four children required liver transplantation for recurrent gastrointestinal haemorrhage. DPM/CHF was confirmed at hepatectomy, with sclerosing small-duct cholangitis. Immunostaining for two primary-cilium axonemal proteins found expression that was deficient intraluminally and ectopic within cholangiocyte cytoplasm. ZFYVE19 depletion in cultured cells yielded abnormalities of centriole and axoneme. CONCLUSION: Biallelic ZFYVE19 mutations can lead to high-GGT cholestasis and DPM/CHF in vivo. In vitro, they can lead to centriolar and axonemal abnormalities. These observations indicate that mutation in ZFYVE19 results, through as yet undefined mechanisms, in a ciliopathy.
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Colangite Esclerosante/genética , Colestase Intra-Hepática/genética , Mutação/genética , Proteínas Oncogênicas/genética , Alelos , Sequência de Aminoácidos , Linhagem Celular Tumoral , Doenças Genéticas Inatas , Células HeLa , Humanos , Cirrose Hepática , Sequenciamento do Exoma/métodosRESUMO
BACKGROUND & AIMS: In about 20% of children with cholestasis and normal or low serum gamma-glutamyltransferase (GGT) activity, no aetiology is identified. We sought new genes implicated in paediatric hepatobiliary disease. METHODS: We conducted whole-exome sequencing in 69 children evaluated at our centre from 2011 to 2018 who had low-GGT cholestasis and in whom homozygous/compound heterozygous predictedly pathogenic variants (PPVs) in ATP8B1, ABCB11, NR1H4, MYO5B or TJP2 were not found. Clinical records and findings on light microscopy and transmission electron microscopy of liver biopsy materials were reviewed. RESULTS: In seven patients from seven unrelated families, biallelic PPVs (10 in total) were found in USP53, recently associated with intrahepatic cholestasis. Seven variants were classified as pathogenic: one canonical splicing, c.569 + 2T > C, and six nonsense or frameshifting: c.169C > T (p.Arg57Ter), c.581delA (p.Arg195GlufsTer38), c.831_832insAG (p.Val279GlufsTer16), c.1012C > T (p.Arg338Ter), c.1426C > T (p.Arg476Ter) and c.1558C > T (p.Arg520Ter). Three were likely pathogenic: c.297G > T (p.Arg99Ser), c.395A > G (p.His132Arg) and c.878G > T (p.Gly293Val). In all patients, jaundice began at age <7 months. Cholestasis was transient, with documented resolution of hyperbilirubinaemia in all (oldest patient now aged 5 years) except one, who was lost to follow-up. Light microscopy identified intralobular cholestasis, giant-cell change of hepatocytes and perisinusoidal-perihepatocytic and portal-tract fibrosis. Ultrastructural study revealed elongated hepatocyte-hepatocyte tight junctions. One patient was deaf. CONCLUSION: USP53 interacts with the tight junction constituent TJP2. TJP2 mutation can cause low-GGT intrahepatic cholestasis, with elongated hepatocyte-hepatocyte tight junctions, as well as deafness. Our findings extend a preliminary report of USP53 disease and indicate that USP53 mutation may generate a partial phenocopy of TJP2 disease.
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Colestase Intra-Hepática , Colestase , Proteases Específicas de Ubiquitina , Criança , Colestase/genética , Colestase Intra-Hepática/genética , Hepatócitos , Humanos , Lactente , Mutação , Proteases Específicas de Ubiquitina/genética , gama-GlutamiltransferaseRESUMO
BACKGROUND: Genetic defects account for a substantial proportion of pediatric cholestasis. This study explored the molecular findings in a large cohort of Chinese patients with inherited cholestasis. METHODS: Between January 2012 and June 2016, 809 Chinese pediatric patients with suspected inherited intrahepatic cholestasis were evaluated by Sanger sequencing and/or panel sequencing. RESULTS: Of the 809 patients, 273 (33.7%) obtained a genetic diagnosis. The rate of positive genetic diagnosis in patients with disease onset at 0-3 month of age was higher than that in patients with disease onset at 4 month of age or later. There were 17 distinct genetic defects diagnosed. The top 4 resulted from mutations in SLC25A13 (44.3%), JAG1 (24.5%), ABCB11 (11.0%), and ATP8B1 (5.9%). All 17 genetic disorders were diagnosed in patients with disease onset at 0-3 months of age; but only 5 were diagnosed in patients with disease onset beyond 4 months of age. A total of 217 distinct pathogenic variants, including 41 novel variants, were identified. Ten recurrent mutations were detected in SLC25A13, ATP8B1, and CYP27A1. They accounted for 48.2% of the total 477 mutant alleles. CONCLUSIONS: There were 17 distinct genetic disorders diagnosed in Chinese pediatric patients with inherited cholestasis.
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Colestase Intra-Hepática/genética , Mutação , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP/genética , Adenosina Trifosfatases/genética , Adolescente , Povo Asiático/genética , Criança , Pré-Escolar , China , Colestanotriol 26-Mono-Oxigenase/genética , Colestase Intra-Hepática/diagnóstico , Colestase Intra-Hepática/etnologia , Feminino , Predisposição Genética para Doença , Hereditariedade , Humanos , Lactente , Proteína Jagged-1/genética , Masculino , Proteínas de Transporte da Membrana Mitocondrial/genética , Linhagem , Fenótipo , Medição de Risco , Fatores de RiscoRESUMO
A frameshift (fs) mutation in the natriuretic peptide precursor A (NPPA) gene, encoding a mutant atrial natriuretic peptide (Mut-ANP), has been linked with familial atrial fibrillation (AF) but the underlying mechanisms by which the mutation causes AF remain unclear. We engineered 2 transgenic (TG) mouse lines expressing the wild-type (WT)-NPPA gene (H-WT-NPPA) and the human fs-Mut-NPPA gene (H-fsMut-NPPA) to test the hypothesis that mice overexpressing the human NPPA mutation are more susceptible to AF and elucidate the underlying electrophysiologic and molecular mechanisms. Transthoracic echocardiography and surface electrocardiography (ECG) were performed in H-fsMut-NPPA, H-WT-NPPA, and Non-TG mice. Invasive electrophysiology, immunohistochemistry, Western blotting and patch clamping of membrane potentials were performed. To examine the role of the Mut-ANP in ion channel remodeling, we measured plasma cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP) levels and protein kinase A (PKA) activity in the 3 groups of mice. In H-fsMut-NPPA mice mean arterial pressure (MAP) was reduced when compared to H-WT-NPPA and Non-TG mice. Furthermore, injection of synthetic fs-Mut-ANP lowered the MAP in H-WT-NPPA and Non-TG mice while synthetic WT-ANP had no effect on MAP in the 3 groups of mice. ECG characterization revealed significantly prolonged QRS duration in H-fsMut-NPPA mice when compared to the other two groups. Trans-Esophageal (TE) atrial pacing of H-fsMut-NPPA mice showed increased AF burden and AF episodes when compared with H-WT-NPPA or Non-TG mice. The cardiac Na+ (NaV1.5) and Ca2+ (CaV1.2/CaV1.3) channel expression and currents (INa, ICaL) and action potential durations (APD90/APD50/APD20) were significantly reduced in H-fsMut-NPPA mice while the rectifier K+ channel current (IKs) was markedly increased when compared to the other 2 groups of mice. In addition, plasma cGMP levels were only increased in H-fsMut-NPPA mice with a corresponding reduction in plasma cAMP levels and PKA activity. In summary, we showed that mice overexpressing an AF-linked NPPA mutation are more prone to develop AF and this risk is mediated in part by remodeling of the cardiac Na+, Ca2+ and K+ channels creating an electrophysiologic substrate for reentrant AF.
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Potenciais de Ação , Fibrilação Atrial/etiologia , Fator Natriurético Atrial/genética , Mutação da Fase de Leitura , Átrios do Coração/fisiopatologia , Miócitos Cardíacos/patologia , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Animais , Fibrilação Atrial/metabolismo , Fibrilação Atrial/patologia , Fator Natriurético Atrial/metabolismo , Fenômenos Eletrofisiológicos , Humanos , Potenciais da Membrana , Camundongos , Camundongos Transgênicos , Miócitos Cardíacos/metabolismoRESUMO
BACKGROUND: Pediatric recurrent acute liver failure (RALF) with recovery between episodes is rare. Causes include autoimmune disease, which may flare and subside; intermittent exposure to toxins, as with ingestions; and metabolic disorders, among them the fever-associated crises ascribed to biallelic mutations in SCYL1, with RALF beginning in infancy. SCYL1 disease manifest with RALF, as known to date, includes central and peripheral neurologic and muscular morbidity (hepatocerebellar neuropathy syndrome). Primary ventilatory and skeletal diseases also have been noted in some reports. CASE SUMMARY: We describe a Han Chinese boy in whom fever-associated RALF began at age 14 mo. Bilateral femoral head abnormalities and mild impairment of neurologic function were first noted aged 8 years 6 mo. Liver biopsy after the third RALF episode (7 years) and during resolution of the fourth RALF episode (8 years 6 mo) found abnormal architecture and hepatic fibrosis, respectively. Whole-exome sequencing revealed homozygosity for the novel frameshift mutation c.92_93insGGGCCCT, p.(H32Gfs*20) in SCYL1 (parental heterozygosity confirmed). CONCLUSION: Our findings expand the mutational and clinical spectrum of SCYL1 disease. In our patient a substantial neurologic component was lacking and skeletal disease was identified relatively late.
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Human induced pluripotent stem cell (hiPSC)-derived atrial cardiomyocytes (CMs) hold great promise for elucidating underlying cellular mechanisms that cause atrial fibrillation (AF). In order to use atrial-like hiPSC-CMs for arrhythmia modeling, it is essential to better understand the molecular and electrophysiological phenotype of these cells. We performed comprehensive molecular, transcriptomic, and electrophysiologic analyses of retinoic acid (RA)-guided hiPSC atrial-like CMs and demonstrate that RA results in differential expression of genes involved in calcium ion homeostasis that directly interact with an RA receptor, chicken ovalbumin upstream promoter-transcription factor 2 (COUP-TFII). We report a mechanism by which RA generates an atrial-like electrophysiologic signature through the downstream regulation of calcium channel gene expression by COUP-TFII and modulation of calcium handling. Collectively, our results provide important insights into the underlying molecular mechanisms that regulate atrial-like hiPSC-CM electrophysiology and support the use of atrial-like CMs derived from hiPSCs to model AF.
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Cálcio/metabolismo , Fenômenos Eletrofisiológicos , Átrios do Coração/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/fisiologia , Potenciais de Ação , Adenosina/metabolismo , Adenosina/farmacologia , Biomarcadores , Carbacol/farmacologia , Diferenciação Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Transcriptoma , Tretinoína/farmacologiaRESUMO
OBJECTIVES: Cerebrotendinous xanthomatosis (CTX) is caused by defects in sterol 27-hydroxylase (CYP27A1, encoded by CYP27A1), a key enzyme in the bile acid synthesis pathway. CTX usually presents as neurologic disease in adults or older children. The rare reports of CTX manifest as neonatal cholestasis assess the cholestasis as transient, with patient survival. Our experience differs. METHODS: Homozygous or compound heterozygous CYP27A1 mutations were detected in 8 neonatal cholestasis patients by whole exome sequencing, panel sequencing, or Sanger sequencing. Their clinical and biochemical data were retrospectively reviewed. Immunostaining for CYP27A1 was conducted in liver of 4 patients. Mass spectrometry was used to analyze patients' urine samples. RESULTS: All 8 infants had severe cholestasis. Five died from, or were transplanted for, liver failure; 3 cleared their jaundice eventually. Marking for CYP27A1 was weak or absent in 3 of the 4 patient specimens. Mass spectrometry of urine revealed a predominance of sulfated and doubly conjugated (sulfated-glucuronidated) bile alcohols. No patient harbored a putatively pathogenic mutation in genes other than CYP27A1 that have been implicated in cholestatic liver disease. CONCLUSIONS: CTX manifest as neonatal cholestasis has a bile acid profile different from CTX manifest in later life, and thus may be overlooked. Immunostaining, mass spectrometry of urine, and genetic studies can support one another in making the diagnosis. A substantial proportion of CTX patients with severe neonatal cholestasis may die or need liver transplantation. CTX manifest in infancy as severe cholestasis warrants further investigation of biochemical diagnostic criteria and best management.
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Colestase/etiologia , Xantomatose Cerebrotendinosa/diagnóstico , Colestanotriol 26-Mono-Oxigenase/genética , Colestanotriol 26-Mono-Oxigenase/metabolismo , Colestase/diagnóstico , Colestase/mortalidade , Colestase/cirurgia , Feminino , Marcadores Genéticos , Humanos , Recém-Nascido , Fígado/metabolismo , Transplante de Fígado , Masculino , Espectrometria de Massas , Mutação , Estudos Retrospectivos , Análise de Sequência de DNA/métodos , Índice de Gravidade de Doença , Xantomatose Cerebrotendinosa/complicações , Xantomatose Cerebrotendinosa/genética , Xantomatose Cerebrotendinosa/metabolismoRESUMO
BACKGROUND: Underlying causes in Chinese children with recurrent acute liver failure (RALF), including liver crises less than full acute liver failure, are incompletely understood. We sought to address this by searching for genes mutated in such children. METHODS: Five unrelated Chinese boys presenting between 2012 and 2015 with RALF of unexplained etiology were studied. Results of whole exome sequencing were screened for mutations in candidate genes. Mutations were verified in patients and their family members by Sanger sequencing. All 5 boys underwent liver biopsy. RESULTS: NBAS was the only candidate gene mutated in more than one patient (biallelic mutations, 3 of 5 patients; 5 separate mutations). All NBAS mutations were novel and predictedly pathogenic (frameshift insertion mutation c.6611_6612insCA, missense mutations c.2407G > A and c.3596G > A, nonsense mutation c.586C > T, and splicing-site mutation c.5389 + 1G > T). Of these mutations, 3 lay in distal (C-terminal) regions of NBAS, a novel distribution. Unlike the 2 patients without NBAS mutations, the 3 patients with confirmed NBAS mutations all suffered from a febrile illness before each episode of liver crisis (fever-related RALF), with markedly elevated alanine aminotransferase and aspartate aminotransferase activities 24-72 h after elevation of body temperature, succeeded by severe coagulopathy and mild to moderate jaundice. CONCLUSIONS: As in other countries, so too in China; NBAS disease is a major cause of fever-related RALF in children. The mutation spectrum of NBAS in Chinese children seems different from that described in other populations.
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Povo Asiático/genética , Febre/genética , Falência Hepática Aguda/genética , Mutação , Proteínas de Neoplasias/genética , Criança , Pré-Escolar , China , Humanos , Lactente , Falência Hepática Aguda/complicações , Masculino , Recidiva , Estudos RetrospectivosRESUMO
Despite a great deal of prior research, the early pathogenic events in natural oral poliovirus infection remain poorly defined. To establish a model for study, we infected 39 macaques by feeding them single high doses of the virulent Mahoney strain of wild type 1 poliovirus. Doses ranging from 107 to 109 50% tissue culture infective doses (TCID50) consistently infected all the animals, and many monkeys receiving 108 or 109 TCID50 developed paralysis. There was no apparent difference in the susceptibilities of the three macaque species (rhesus, cynomolgus, and bonnet) used. Virus excretion in stool and nasopharynges was consistently observed, with occasional viremia, and virus was isolated from tonsils, gut mucosa, and draining lymph nodes. Viral replication proteins were detected in both epithelial and lymphoid cell populations expressing CD155 in the tonsil and intestine, as well as in spinal cord neurons. Necrosis was observed in these three cell types, and viral replication in the tonsil/gut was associated with histopathologic destruction and inflammation. The sustained response of neutralizing antibody correlated temporally with resolution of viremia and termination of virus shedding in oropharynges and feces. For the first time, this model demonstrates that early in the infectious process, poliovirus replication occurs in both epithelial cells (explaining virus shedding in the gastrointestinal tract) and lymphoid/monocytic cells in tonsils and Peyer's patches (explaining viremia), extending previous studies of poliovirus pathogenesis in humans. Because the model recapitulates human poliovirus infection and poliomyelitis, it can be used to study polio pathogenesis and to assess the efficacy of candidate antiviral drugs and new vaccines.IMPORTANCE Early pathogenic events of poliovirus infection remain largely undefined, and there is a lack of animal models mimicking natural oral human infection leading to paralytic poliomyelitis. All 39 macaques fed with single high doses ranging from 107 to 109 TCID50 Mahoney type 1 virus were infected, and many of the monkeys developed paralysis. Virus excretion in stool and nasopharynges was consistently observed, with occasional viremia; tonsil, mesentery lymph nodes, and intestinal mucosa served as major target sites of viral replication. For the first time, this model demonstrates that early in the infectious process, poliovirus replication occurs in both epithelial cells (explaining virus shedding in the gastrointestinal tract) and lymphoid/monocytic cells in tonsils and Peyer's patches (explaining viremia), thereby supplementing historical reconstructions of poliovirus pathogenesis. Because the model recapitulates human poliovirus infection and poliomyelitis, it can be used to study polio pathogenesis, candidate antiviral drugs, and the efficacy of new vaccines.
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Macaca , Poliomielite/patologia , Poliovirus/crescimento & desenvolvimento , Poliovirus/patogenicidade , Estruturas Animais/virologia , Animais , Modelos Animais de Doenças , Células Epiteliais/virologia , Fezes/virologia , Leucócitos/virologia , Nasofaringe/virologia , Eliminação de Partículas ViraisRESUMO
Hereditary cholestasis in childhood and infancy with normal serum gamma-glutamyltransferase (GGT) activity is linked to several genes. Many patients, however, remain genetically undiagnosed. Defects in myosin VB (MYO5B; encoded by MYO5B) cause microvillus inclusion disease (MVID; MIM251850) with recurrent watery diarrhea. Cholestasis, reported as an atypical presentation in MVID, has been considered a side effect of parenteral alimentation. Here, however, we report on 10 patients who experienced cholestasis associated with biallelic, or suspected biallelic, mutations in MYO5B and who had neither recurrent diarrhea nor received parenteral alimentation. Seven of them are from two study cohorts, together comprising 31 undiagnosed low-GGT cholestasis patients; 3 are sporadic. Cholestasis in 2 patients was progressive, in 3 recurrent, in 2 transient, and in 3 uncategorized because of insufficient follow-up. Liver biopsy specimens revealed giant-cell change of hepatocytes and intralobular cholestasis with abnormal distribution of bile salt export pump (BSEP) at canaliculi, as well as coarse granular dislocation of MYO5B. Mass spectrometry of plasma demonstrated increased total bile acids, primary bile acids, and conjugated bile acids, with decreased free bile acids, similar to changes in BSEP-deficient patients. Literature review revealed that patients with biallelic mutations predicted to eliminate MYO5B expression were more frequent in typical MVID than in isolated-cholestasis patients (11 of 38 vs. 0 of 13). CONCLUSION: MYO5B deficiency may underlie 20% of previously undiagnosed low-GGT cholestasis. MYO5B deficiency appears to impair targeting of BSEP to the canalicular membrane with hampered bile acid excretion, resulting in a spectrum of cholestasis without diarrhea. (Hepatology 2017;65:1655-1669).
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Subfamília B de Transportador de Cassetes de Ligação de ATP/deficiência , Colestase Intra-Hepática/genética , Cadeias Pesadas de Miosina/genética , Miosina Tipo V/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/sangue , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/metabolismo , Ácidos e Sais Biliares/sangue , Colestase Intra-Hepática/sangue , Colestase Intra-Hepática/patologia , Análise Mutacional de DNA , Exoma , Feminino , Humanos , Lactente , Recém-Nascido , Fígado/metabolismo , Fígado/patologia , Masculino , Cadeias Pesadas de Miosina/metabolismo , Miosina Tipo V/metabolismo , Estudos RetrospectivosRESUMO
BACKGROUND: Fibrinogen storage disease (FSD) is a rare autosomal-dominant disorder caused by mutation in FGG, encoding the fibrinogen gamma chain. Here we report the first Han Chinese patient with FSD, caused by de novo fibrinogen Aguadilla mutation, and his response to pharmacologic management. CASE PRESENTATION: Epistaxis and persistent clinical-biochemistry test-result abnormalities prompted liver biopsy in a boy, with molecular study of FGG in him and his parents. He was treated with the autophagy enhancer carbamazepine, reportedly effective in FSD, and with ursodeoxycholic acid thereafter. Inclusion bodies in hepatocellular cytoplasm stained immune-histochemically for fibrinogen. Selective analysis of FGG found the heterozygous mutation c.1201C > T (p.Arg401Trp), absent in both parents. Over more than one year's follow-up, transaminase and gamma-glutamyl transpeptidase activities have lessened but not normalized. CONCLUSION: This report expands the epidemiology of FSD and demonstrates idiosyncrasy in response to oral carbamazepine and/or ursodeoxycholic acid in FSD.
Assuntos
Afibrinogenemia/tratamento farmacológico , Afibrinogenemia/genética , Povo Asiático/genética , Carbamazepina/uso terapêutico , Fibrinogênios Anormais/genética , Ácido Ursodesoxicólico/uso terapêutico , Pré-Escolar , Genes Dominantes , Humanos , Masculino , Mutação , Resultado do TratamentoRESUMO
Resveratrol (trans-3,4',5-trihydroxystilbene) has been shown to exert potent anticancer effects on various types of cancer through its anti-proliferative, anti-angiogenic, antioxidant and pro-apoptotic functions. There is still a lack of experimental evidence regarding whether resveratrol has potential anticancer activity in human nasopharyngeal carcinoma (NPC) cells. The purpose of this study was to explore the anticancer activity of resveratrol in human NPC cells both in vitro and in vivo. Our results indicated that treatment with resveratrol led to a time- and dose-dependent decrease in cell proliferation in NPC cells. A dose-dependent increase in apoptosis in response to resveratrol treatment was also observed in NPC cells. Flow cytometric analysis showed that treatment of NPC cells with resveratrol led to cell cycle arrest at the S and G2/M phases. Mechanistically, resveratrol treatment downregulated the expression of Bcl-2 and hypoxia-inducible factor-1α (HIF-1α) proteins and upregulated the expression of caspase-3 protein. In addition, resveratrol treatment also significantly decreased the phosphorylation levels of Akt1, p70S6K and p-4E-BP-1 and the protein expression of several cyclins involved in cell cycle regulation. In vivo studies further showed that resveratrol was able to significantly inhibit the growth of NPC tumor xenografts in nude mice. Collectively, our findings suggest that resveratrol exerts potent anti-prolife-rative and pro-apoptotic effects on human NPC cells possibly through interfering with the pAkt1/p70S6K signaling pathways, thus it may potentially be developed as an effective agent for chemoprevention and chemotherapy of human NPC.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Nasofaríngeas/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinoma , Caspase 3/biossíntese , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular , Ciclinas/metabolismo , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/biossíntese , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Transplante de Neoplasias , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Resveratrol , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Estilbenos/uso terapêutico , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Ginkgo biloba is a dioecious tree and its extract is a complex mixture that has been used for thousands of years to treat a variety of ailments in traditional Chinese medicine. The aim of this study was to present our observations on the inhibitory effects of different Ginkgo biloba extracts on human breast cancer cell proliferation and growth. Our results demonstrated that treatment of MCF-7 and MDA-MB-231 human breast cancer cells with Ginkgo biloba leaves and ginkgo fruit extract inhibited cell proliferation. It was also observed that this inhibition was accompanied by the enhancement of cytochrome P450 (CYP) 1B1 expression in MDA-MB-231 cells. In addition, treatment with ginkgo fruit extract resulted in a higher CYP1B1 expression in MDA-MB-231 cells compared to treatment with the Ginkgo biloba leaves extract. Our results suggested that the inhibitory effects of the Ginkgo biloba extract on estrogen receptor-negative breast cancer proliferation and the induction of CYP1B1 expression may be exerted through an alternative pathway, independent of the estrogen receptor or the aryl hydrocarbon receptor pathway.
RESUMO
Bax inhibitor-1 (Bi-1), an anti-apoptotic protein that belongs to the Bcl-2 family, plays an important role in the mitochondrial apoptosis pathway to suppress Bax-induced apoptosis. In several human cancers, including nasopharyngeal carcinoma, its expression was found to be increased; however, up-regulated expression of this protein has been linked to increased cell proliferations. In this study, we down-regulated the gene expression of Bi-1 in nasopharyngeal carcinoma cells by using a lentivirus transfection system packed with short hairpin RNA targeting Bi-1 and used an in vivo model to assess its efficacy as a target in human gene therapy. The data indicated that human malignant nasopharyngeal carcinoma cells, CNE-1 and SUNE-1, transfected with lentiviral short hairpin RNA targeting Bi-1 grew more slowly and showed a higher degree of apoptosis. Moreover, the tumorigenicity of CNE-1 was significantly suppressed when inoculated mice were intratumorically injected with the same vector. Taken together, these data lead us to conclude that Bi-1 plays a crucial role in CNE-1 tumorigenesis and that Bi-1 may be a novel therapeutic target for nasopharyngeal carcinoma.