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1.
Br J Haematol ; 203(4): 673-677, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37592722

RESUMO

Platelet-type von Willebrand disease (PT-VWD) is a rare autosomal dominant bleeding disorder characterized by an increased ristocetin-induced platelet aggregation (RIPA) and enhanced affinity of platelet glycoprotein Ibα (GPIbα) to von Willebrand factor (VWF). To date, only seven variants have been described with this gain-of-function effect, most of them located in the C-terminal disulphide loop of the VWF-binding domain of GPIbα. We herein describe a patient with moderate bleeding symptoms, mild thrombocytopenia and increased RIPA. By direct sequencing of GP1BA, a novel leucine-rich repeat heterozygous variant was identified (c.580C>T; predictably p.Leu194Phe), strongly suggestive as being the underlying cause for the PT-VWD phenotype of our patient.


Assuntos
Doenças de von Willebrand , Fator de von Willebrand , Humanos , Fator de von Willebrand/genética , Mutação com Ganho de Função , Doenças de von Willebrand/diagnóstico , Plaquetas , Hemorragia/genética , Complexo Glicoproteico GPIb-IX de Plaquetas/genética
2.
Saudi Pharm J ; 28(12): 1499-1506, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33424243

RESUMO

Osteoarthritis (OA) is a disease characterized by degeneration of the joint complex due to cartilage destruction. Fraxetin, a widely used and studied coumarin compound extracted from a traditional Chinese herb (Qin Pi), has shown anti-inflammatory and antioxidant properties, but its effects on OA have not been studied. In the present study, western blotting, immunofluorescence, and terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) were used to evaluate the effects of fraxetin on IL-1ß-induced apoptotic activity, inflammatory responses, and catabolism in rat chondrocytes. The results showed that fraxetin prevented IL-1ß-induced apoptosis of chondrocytes and inhibited inflammatory mediator release by regulating the Toll-like receptor 4 (TLR4)/myeloid differentiation primary response 88 (MyD88)/nuclear factor (NF)-κB pathway in chondrocytes. Additionally, fraxetin suppressed the upregulation of matrix metalloproteinase 13 (MMP13) and degradation of collagen II in the extracellular matrix (ECM). Moreover, the effects of fraxetin in vivo were assessed in a monosodium iodoacetate (MIA)-induced rat model of OA using hematoxylin and eosin (H&E) and Safranin O-fast green staining and magnetic resonance imaging (MRI). The results showed that fraxetin protected the cartilage against destruction. In conclusion, fraxetin could be a potential therapeutic for OA.

3.
J Proteome Res ; 18(3): 1441-1445, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30761899

RESUMO

The analysis of cells and tissue by bottom-up proteomics starts with lysis, followed by in-solution digestion. Lysis buffers commonly used include detergents and other reagents for achieving efficient protein solubility. However, these reagents are, for the most part, incompatible with downstream analytical instrumentation. One method for in-solution digestion and cleanup, termed suspension trapping (S-Trap), has been recently introduced. We present an evaluation of the compatibility of commonly used lysis buffers with S-Trap: SDS, urea, NP-40, RIPA, and SDS with DTT (SDT). We show that S-Trap is compatible with all of the tested buffers, with SDS and SDT performing the best. On the basis of these data, we anticipate that the method will transform experimental planning for mass-spectrometry-based proteomics, making it far more flexible and tolerable of various lysis buffers. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE partner repository with the data set identifier PXD011665.


Assuntos
Detergentes/química , Fosfoproteínas/isolamento & purificação , Proteômica/métodos , Espectrometria de Massas em Tandem/métodos , Soluções Tampão , Células HeLa , Humanos , Octoxinol/química , Fosfoproteínas/química , Manejo de Espécimes
4.
Electrophoresis ; 37(20): 2595-2601, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27445231

RESUMO

Determination of protein concentration is often an absolute prerequisite in preparing samples for biochemical and proteomic analyses. However, current protein assay methods are not compatible with both reducers and detergents, which are however present simultaneously in most denaturing extraction buffers used in proteomics and electrophoresis, and in particular in SDS electrophoresis. It was found that inclusion of cyclodextrins in a Coomassie blue-based assay made it compatible with detergents, as cyclodextrins complex detergents in a 1:1 molecular ratio. As this type of assay is intrinsically resistant to reducers, a single-step assay that is both detergent and reducer compatible was developed. Depending on the type and concentration of detergents present in the sample buffer, either beta-cyclodextrin or alpha-cyclodextrin can be used, the former being able to complex a wider range of detergents and the latter being able to complex higher amounts of detergents due to its greater solubility in water. Cyclodextrins are used at final concentrations of 2-10 mg/mL in the assay mix. This typically allows to measure samples containing as little as 0.1 mg/mL protein, in the presence of up to 2% detergent and reducers such as 5% mercaptoethanol or 50 mM DTT in a single step with a simple spectrophotometric assay.


Assuntos
Técnicas de Química Analítica/métodos , Ciclodextrinas/química , Detergentes/química , Indicadores e Reagentes/química , Proteínas/análise , Corantes de Rosanilina/química , Animais , Bovinos , Camundongos , Células RAW 264.7 , Soroalbumina Bovina
5.
Epidemiol Infect ; 144(5): 1010-3, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25170765

RESUMO

Chagas disease is an important emerging disease in Texas that results in cardiomyopathy in about 30% of those infected with the parasite Trypanosoma cruzi. Between the years 2008 and 2012, about 1/6500 blood donors were T. cruzi antibody-confirmed positive. We found older persons and minority populations, particularly Hispanic, at highest risk for screening positive for T. cruzi antibodies during routine blood donation. Zip code analysis determined that T. cruzi is associated with poverty. Chagas disease has a significant disease burden and is a cause of substantial economic losses in Texas.


Assuntos
Doadores de Sangue/estatística & dados numéricos , Doença de Chagas/epidemiologia , Programas de Rastreamento , Trypanosoma cruzi/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antiprotozoários/sangue , Doença de Chagas/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Fatores Socioeconômicos , Texas/epidemiologia , Adulto Jovem
6.
Biochim Biophys Acta ; 1843(2): 316-26, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24286864

RESUMO

Microrchidia (MORC) family CW-type zinc finger 2 (MORC2) has been shown to be involved in several nuclear processes, including transcription modulation and DNA damage repair. However, its cytosolic function remains largely unknown. Here, we report an interaction between MORC2 and adenosine triphosphate (ATP)-citrate lyase (ACLY), an enzyme that catalyzes the formation of acetyl-coA and plays a central role in lipogenesis, cholesterogenesis, and histone acetylation. Furthermore, we demonstrate that MORC2 promotes ACLY activation in the cytosol of lipogenic breast cancer cells and plays an essential role in lipogenesis, adipogenesis and differentiation of 3T3-L1 preadipocytic cells. Consistently, the expression of MORC2 is induced during the process of 3T3-L1 adipogenic differentiation and mouse mammary gland development at a stage of increased lipogenesis. This observation was accompanied by a high ACLY activity. Together, these results demonstrate a cytosolic function of MORC2 in lipogenesis, adipogenic differentiation, and lipid homeostasis by regulating the activity of ACLY.


Assuntos
Adipogenia , Citosol/metabolismo , Lipogênese , Fatores de Transcrição/metabolismo , Células 3T3-L1 , ATP Citrato (pro-S)-Liase/metabolismo , Animais , Diferenciação Celular , Ativação Enzimática , Ácidos Graxos/metabolismo , Humanos , Células MCF-7 , Ácido Mevalônico/metabolismo , Camundongos , Modelos Biológicos , Ligação Proteica , Transdução de Sinais
7.
Biochim Biophys Acta ; 1840(1): 332-43, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23954204

RESUMO

BACKGROUND: Altered cellular bioenergetics and oxidative stress are emerging hallmarks of most cancers including pancreatic cancer. Elevated levels of intrinsic reactive oxygen species (ROS) in tumors make them more susceptible to exogenously induced oxidative stress. Excessive oxidative insults overwhelm their adaptive antioxidant capacity and trigger ROS-mediated cell death. Recently, we have discovered a novel class of quinazolinediones that exert their cytotoxic effects by modulating ROS-mediated signaling. METHODS: Cytotoxic potential was determined by colorimetric and colony formation assays. An XF24 Extracellular Flux Analyzer, and colorimetric and fluorescent techniques were used to assess the bioenergetics and oxidative stress effects, respectively. Mechanism was determined by Western blots. RESULTS: Compound 3a (6-[(2-acetylphenyl)amino]quinazoline-5,8-dione) was identified through a medium throughput screen of ~1000 highly diverse in-house compounds and chemotherapeutic agents for their ability to alter cellular bioenergetics. Further structural optimizations led to the discovery of a more potent analog, 3b (6-[(3-acetylphenyl)amino]quinazoline-5,8-dione) that displayed anti-proliferative activities in low micromolar range in both drug-sensitive and drug-resistant cancer cells. Treatment with 3b causes Akt activation resulting in increased cellular oxygen consumption and oxidative stress in pancreatic cancer cells. Moreover, oxidative stress induced by 3b promoted activation of stress kinases (p38/JNK) resulting in cancer cell death. Treatment with antioxidants was able to reduce cell death confirming ROS-mediated cytotoxicity. CONCLUSION: In conclusion, our novel quinazolinediones are promising lead compounds that selectively induce ROS-mediated cell death in cancer cells and warrant further preclinical studies. GENERAL SIGNIFICANCE: Since 3b (6-[(3-acetylphenyl)amino]quinazoline-5,8-dione) exerts Akt-dependent ROS-mediated cell death, it might provide potential therapeutic options for chemoresistant and Akt-overexpressing cancers.


Assuntos
Apoptose/efeitos dos fármacos , Desenho de Fármacos , Metabolismo Energético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Quinazolinonas/farmacologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Humanos , Estrutura Molecular , Oxirredução , Consumo de Oxigênio/efeitos dos fármacos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Quinazolinonas/síntese química , Quinazolinonas/química , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco
8.
Can J Infect Dis Med Microbiol ; 26(3): 157-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26236358

RESUMO

Chagas disease (CD) is a protozoan infection caused by Trypanosoma cruzi, which is transmitted by triatomine insect vectors in parts of Latin America. In a nonendemic country, such as Canada, spread can still occur via vertical transmission, and infected blood or organ donations. The Canadian Blood Services and Héma-Québec have both implemented selective screening of blood donors for CD based on risk factors. In 2011, Héma-Québec identified two seropositive 'at-risk' Chilean siblings who had donated blood in Montreal, Quebec. They were referred to the JD MacLean Centre for Tropical Diseases (Montreal, Quebec) for confirmatory testing (T cruzi excreted-secreted antigen ELISA, polymerase chain reaction and/or radioimmunoprecipitation assay) and follow-up. Screening of the rest of the family revealed two other seropositive family members (the mother and sister). While their geographical history in Chile suggests vectorial transmission, this family cluster of CD raises the possibility of vertical transmission. Congenital infection should always be considered among CD-positive mothers and pregnant women. With blood donor screening, Canadian physicians will increasingly see patients with CD and should know how to manage them appropriately. In addition to the case presentation, the authors review the transmission, screening and clinical management of CD in a nonendemic context.


La maladie de Chagas (MC) est une infection protozoaire causée par le Trypanosoma cruzi, transmis par des vecteurs d'insectes du genre triatomine dans certaines régions d'Amérique latine. Dans un pays non endémique comme le Canada, la propagation est possible par transmission verticale et par les dons de sang ou d'organes infectés. La Société canadienne du sang et Héma-Québec ont tous deux adopté le dépistage sélectif des donneurs de sang pour déceler la MC en fonction des facteurs de risque. En 2011, Héma-Québec a repéré deux membres d'une fratrie chilienne séropositifs « à risque ¼ qui avaient donné du sang à Montréal, au Québec. Ils ont été orientés vers le Centre des maladies tropicales JD MacLean de Montréal pour subir des tests de confirmation (test ELISA des antigènes excrétés-sécrétés par T cruzi, réaction en chaîne de la polymérase ou test de radio-immunoprécipitation) et profiter d'un suivi. Le dépistage du reste de la famille a révélé deux autres membres séropositifs (la mère et la sœur). Étant donné leur origine géographique, on pourrait subodorer une transmission vectorielle, mais la grappe familiale de MC soulève la possibilité d'une transmission verticale. L'infection congénitale devrait toujours être envisagée chez les mères et les femmes enceintes positives à la MC. Grâce au dépistage des donneurs de sang, les médecins canadiens verront de plus en plus de patients atteints de la MC. Ils devraient donc savoir comment la prendre en charge correctement. En plus de la présentation de cas, les auteurs passent en revue la transmission, le dépistage et la prise en charge clinique de la MC dans un contexte non endémique.

9.
Biochim Biophys Acta ; 1829(10): 1102-10, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23932921

RESUMO

In various human malignancies, widespread dysregulation of microRNA (miRNA) expression is reported to occur and affects various cell growth programs. Recent studies suggest that the expression levels of miRNAs that act as tumor suppressors are frequently reduced in cancers because of chromosome deletions, epigenetical changes, aberrant transcription, and disturbances in miRNA processing. MiR-143 and -145 are well-recognized miRNAs that are highly expressed in several tissues, but down-regulated in most types of cancers. However, the mechanism of this down-regulation has not been investigated in detail. Here, we show that DEAD-box RNA helicase 6, DDX6 (p54/RCK), post-transcriptionally down-regulated miR-143/145 expression by prompting the degradation of its host gene product, NCR143/145 RNA. In human gastric cancer cell line MKN45, DDX6 protein was abundantly expressed and accumulated in processing bodies (P-bodies). DDX6 preferentially increased the instability of non-coding RNA, NCR143/145, which encompasses the miR-143/145 cluster, and down-regulated the expression of mature miR-143/145. In human monocytic cell line THP-1, lipopolysaccharide treatment promoted the assembly of P-bodies and down-regulated the expression of NCR143/145 and its miR-143/145 rapidly. In these cells, cycloheximide treatment led to a loss of P-bodies and to an increase in NCR143/145 RNA stability, thus resulting in up-regulation of miR-143/145 expression. These data demonstrate that DDX6 contributed to the control of NCR143/145 RNA stability in P-bodies and post-transcriptionally regulated miR-143/145 expression in cancer cells.


Assuntos
RNA Helicases DEAD-box/metabolismo , Regulação da Expressão Gênica , MicroRNAs/antagonistas & inibidores , Neoplasias da Próstata/genética , Proteínas Proto-Oncogênicas/metabolismo , Processamento Pós-Transcricional do RNA , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Western Blotting , Células Cultivadas , RNA Helicases DEAD-box/antagonistas & inibidores , RNA Helicases DEAD-box/genética , Imunofluorescência , Humanos , Luciferases/metabolismo , Masculino , MicroRNAs/genética , Monócitos/citologia , Monócitos/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/metabolismo
10.
Acta Crystallogr D Biol Crystallogr ; 70(Pt 9): 2295-300, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25195744

RESUMO

RipA is a key cysteine protease of Mycobacterium tuberculosis as it is responsible for bacterial daughter-cell separation. Although it is an important target for antimicrobial development, its mechanism of action and its interaction pattern with its substrate are hitherto unknown. By combining crystallographic and mutational studies with functional assays and molecular modelling, it is shown that the catalytic activity of the enzyme relies on a Cys-His-Glu triad and the impact of the mutation of each residue of the triad on the structure and function of RipA is analysed. Unexpectedly, the crystallographic analyses reveal that mutation of the glutamic acid to alanine results in inversion of the configuration of the catalytic cysteine. The consequent burial of the catalytic cysteine side chain explains the enzyme inactivation upon mutation. These data point to a novel role of the acidic residue often present in the triad of cysteine proteases as a supervisor of cysteine configuration through preservation of the local structural integrity.


Assuntos
Proteínas de Bactérias/genética , Divisão Celular , Citosina/metabolismo , Mutação , Mycobacterium tuberculosis/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sequência de Bases , Biocatálise , Dicroísmo Circular , Clonagem Molecular , Primers do DNA , Modelos Moleculares , Mycobacterium tuberculosis/citologia , Reação em Cadeia da Polimerase , Conformação Proteica
11.
RNA Biol ; 11(9): 1137-47, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25483046

RESUMO

Megakaryocytes exit from mitotic cell cycle and enter a phase of repeated DNA replication without undergoing cell division, in a process termed as endomitosis of which little is known. We studied the expression of a DNA replication licensing factor mini chromosome maintenance protein 7 (MCM7) and its intronic miR-106b-25 cluster during mitotic and endo-mitotic cycles in megakaryocytic cell lines and in vitro cultured megakaryocytes obtained from human cord blood derived CD34(+) cells. Our results show that contrary to mitotic cell cycle, endomitosis proceeds with an un-coupling of the expression of MCM7 and miR-106b-25. This was attributed to the presence of a transcript variant of MCM7 which undergoes nonsense mediated decay (NMD). Additionally, miR-25 which was up regulated during endomitosis was found to promote megakaryopoiesis by inhibiting the expression of PTEN. Our study thus highlights the importance of a transcript variant of MCM7 destined for NMD in the modulation of megakaryopoiesis.


Assuntos
Regulação da Expressão Gênica , Íntrons/genética , Megacariócitos/metabolismo , MicroRNAs/genética , Componente 7 do Complexo de Manutenção de Minicromossomo/genética , Poliploidia , Western Blotting , Ciclo Celular/fisiologia , Proliferação de Células , Células Cultivadas , Replicação do DNA , Sangue Fetal/citologia , Sangue Fetal/metabolismo , Citometria de Fluxo , Humanos , Imunoprecipitação , Megacariócitos/citologia , MicroRNAs/metabolismo , Microscopia Confocal , Componente 7 do Complexo de Manutenção de Minicromossomo/metabolismo , Mitose/fisiologia , Degradação do RNAm Mediada por Códon sem Sentido/fisiologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativação Transcricional
12.
Bioorg Med Chem ; 22(3): 1029-39, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24398380

RESUMO

High-throughput screening of a small-molecule library identified a 5-triazolo-2-arylpyridazinone as a novel inhibitor of the important glycolytic enzyme 6-phosphofructo-2-kinase/2,6-bisphosphatase 3 (PFKFB3). Such inhibitors are of interest due to PFKFB3's control of the important glycolytic pathway used by cancer cells to generate ATP. A series of analogues was synthesized to study structure-activity relationships key to enzyme inhibition. Changes to the triazolo or pyridazinone rings were not favoured, but limited-size substitutions on the aryl ring provided modest increases in potency against the enzyme. Selected analogues and literature-described inhibitors were evaluated for their ability to suppress the glycolytic pathway, as detected by a decrease in lactate production, but none of these compounds demonstrated such suppression at non-cytotoxic concentrations.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Fosfofrutoquinase-2/antagonistas & inibidores , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Técnicas de Química Sintética , Avaliação Pré-Clínica de Medicamentos/métodos , Glicólise/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Piridazinas/química , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade
13.
Sci Rep ; 14(1): 3834, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38360971

RESUMO

Glaucoma is a prevalent cause of blindness globally, characterized by the progressive degeneration of retinal ganglion cells (RGCs). Among various factors, glutamate excitotoxicity stands out as a significant contributor of RGCs loss in glaucoma. Our study focused on Ripa-56 and its protective effect against NMDA-induced retinal damage in mice, aiming to delve into the potential underlying mechanism. The R28 cells were categorized into four groups: glutamate (Glu), Glu + Ripa-56, Ripa-56 and Control group. After 24 h of treatment, cell death was assessed by PI / Hoechst staining. Mitochondrial membrane potential changes, apoptosis and reactive oxygen species (ROS) production were analyzed using flow cytometry. The alterations in the expression of RIP-1, p-MLKL, Bcl-2, BAX, Caspase-3, Gpx4 and SLC7A11 were examined using western blot analysis. C57BL/6j mice were randomly divided into NMDA, NMDA + Ripa-56, Ripa-56 and control groups. Histological changes in the retina were evaluated using hematoxylin and eosin (H&E) staining. RGCs survival and the protein expression changes of RIP-1, Caspase-3, Bcl-2, Gpx4 and SLC7A11 were observed using immunofluorescence. Ripa-56 exhibited a significant reduction in the levels of RIP-1, p-MLKL, Caspase-3, and BAX induced by glutamate, while promoting the expression of Bcl-2, Gpx-4, and SLC7A1 in the Ripa-56-treated group. In our study, using an NMDA-induced normal tension glaucoma mice model, we employed immunofluorescence and H&E staining to observe that Ripa-56 treatment effectively ameliorated retinal ganglion cell loss, mitigating the decrease in retinal ganglion cell layer and bipolar cell layer thickness caused by NMDA. In this study, we have observed that Ripa-56 possesses remarkable anti- necroptotic, anti-apoptotic and anti-ferroptosis properties. It demonstrates the ability to combat not only glutamate-induced excitotoxicity in R28 cells, but also NMDA-induced retinal excitotoxicity in mice. Therefore, Ripa-56 could be used as a potential retinal protective agent.


Assuntos
Glaucoma , Células Ganglionares da Retina , Animais , Camundongos , Células Ganglionares da Retina/patologia , Caspase 3/metabolismo , N-Metilaspartato/metabolismo , Ácido Glutâmico/metabolismo , Proteína X Associada a bcl-2/metabolismo , Camundongos Endogâmicos C57BL , Retina/patologia , Apoptose , Glaucoma/patologia
14.
Int Immunopharmacol ; 133: 112060, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38652970

RESUMO

Acute respiratory distress syndrome (ARDS) is characterized by lung tissue oedema and inflammatory cell infiltration, with limited therapeutic interventions available. Receptor-interacting protein kinase 1 (RIPK1), a critical regulator of cell death and inflammation implicated in many diseases, is not fully understood in the context of ARDS. In this study, we employed RIP1 kinase-inactivated (Rip1K45A/K45A) mice and two distinct RIPK1 inhibitors to investigate the contributions of RIP1 kinase activity in lipopolysaccharide (LPS)-induced ARDS pathology. Our results indicated that RIPK1 kinase inactivation, achieved through both genetic and chemical approaches, significantly attenuated LPS-induced ARDS pathology, as demonstrated by reduced polymorphonuclear neutrophil percentage (PMN%) in alveolar lavage fluid, expression of inflammatory and fibrosis-related factors in lung tissues, as well as histological examination. Results by tunnel staining and qRT-PCR analysis indicated that RIPK1 kinase activity played a role in regulating cell apoptosis and inflammation induced by LPS administration in lung tissue. In summary, employing both pharmacological and genetic approaches, this study demonstrated that targeted RIPK1 kinase inactivation attenuates the pathological phenotype induced by LPS inhalation in an ARDS mouse model. This study enhances our understanding of the therapeutic potential of RIPK1 kinase modulation in ARDS, providing insights for the pathogenesis of ARDS.


Assuntos
Lipopolissacarídeos , Inibidores de Proteínas Quinases , Proteína Serina-Treonina Quinases de Interação com Receptores , Síndrome do Desconforto Respiratório , Animais , Humanos , Masculino , Camundongos , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Pulmão/patologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Neutrófilos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/imunologia
15.
Clin Biochem ; : 110826, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39357636

RESUMO

Acquired myasthenia gravis (MG) is an autoimmune disease targeting the specific proteins in the postsynaptic muscle membrane. 50% of ocular and 80% of generalized MG have acetylcholine receptor antibodies (AChR Abs). 1-10% of MG patients have antibodies against muscle-specific kinase (MuSK), and 2-50 % of seronegative MG cases have antibodies against lipoprotein-receptor-related protein4 antibodies (LRP4 Abs). Serological testing is crucial for diagnosing and determining the appropriate therapeutic approach for MG patients. The radioimmunoprecipitation assay (RIPA) method is a historical standard test for detecting the AChR Abs and MuSK Abs. While it has nearly 100% specificity in the AChR Abs detection, its sensitivity is between 50--92%. The sensitivity and specificity of RIPA for detecting MuSK Abs is much lower. The fixed and live Cell-Based assays (f-CBA and L- CBA) have higher sensitivity than RIPA. With advancements in the serological diagnosis and management of MG, we now recommend a complete reflex testing algorithm on the first pretreatment sample of a suspected MG patient, starting with the binding and blocking assays for AChR Abs by RIPA and/ or f-CBA. If AChR Ab is negative, then reflex to MuSK Abs by RIPA and/ or CBAs. If AChR and MuSK Abs are negative, then use clustered L-CBA by request.

16.
Biochem Biophys Res Commun ; 441(2): 383-6, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24157792

RESUMO

Hepcidin is a peptide hormone that is secreted by the liver and that functions as the central regulator of systemic iron metabolism in mammals. Its expression is regulated at the transcriptional level by changes in iron status and iron requirements, and by inflammatory cues. There is considerable interest in understanding the mechanisms that influence hepcidin expression because dysregulation of hepcidin production is associated with a number of disease states and can lead to iron overload or iron-restricted anemia. In order to shed light on the factors that alter hepcidin expression, we carried out experiments with HepG2 and HuH7, human hepatoma cell lines that are widely used for this purpose. We found that the addition of heat-inactivated fetal calf serum to these cells resulted in a significant dose- and time-dependent up-regulation of hepcidin expression. Serum also activated signaling events known to be downstream of bone morphogenetic proteins (BMPs), a group of molecules that have been implicated previously in hepcidin regulation. Inhibition of these signals with dorsomorphin significantly suppressed serum-induced hepcidin up-regulation. Our results indicate that a BMP or BMP-like molecule present in serum may play an important role in regulating hepcidin expression.


Assuntos
Proteínas Morfogenéticas Ósseas/sangue , Hepcidinas/biossíntese , Fígado/metabolismo , Soro/metabolismo , Animais , Bovinos , Células Hep G2 , Hepcidinas/genética , Humanos , Pirazóis/farmacologia , Pirimidinas/farmacologia , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Regulação para Cima
17.
Ann Transl Med ; 11(7): 290, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37090043

RESUMO

Myasthenia gravis (MG) is the most common immune-mediated disorder of the neuromuscular junction. Anti-acetylcholine receptor (anti-AChR), anti-muscle-specific kinase (anti-MuSK), and anti-lipoprotein receptor-related protein 4 (anti-LRP4) antibodies are the three well-defined pathogenic antibodies. Patients with MG can also have other antibodies, such as anti-titin, anti-ryanodine receptor (anti-RyR), anti-Agrin and anti-KV1.4 antibodies. Since MG is heterogeneous in terms of pathophysiology, antibody status, and other factors, serological tests are crucial for clinical diagnosis confirmation and treatment choice. Herein, we review the different methods for detection of various antibodies involved in MG and their sensitivity and specificity. The understanding of these elements should be useful for improving the diagnosis and determining how to adapt the existing therapies to the requirements of each patient.

18.
J Orthop Translat ; 39: 34-42, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36636358

RESUMO

Background: Osteosarcoma (OS) is the most common primary malignancy in bone tissues, and effective therapeutics remain absent in clinical practice. Traditional Chinese medicines (TCM) have been used for thousands of years, which provide great insights into OS management. Gallic acid (GA) is a natural phenolic acid enriched in various foods and herbs. Several pharmacological activities of GA such as anti-oxidation and anti-inflammation have been well-established. However, its biological function in OS remains not fully understood. Methods: The potential anti-cancer properties of GA were evaluated in 143 â€‹B, U2OS and MG63 â€‹cells. Its effects on cell growth, cell cycle, apoptosis and migration were examined in these OS cells. The lncRNA H19 and Wnt/ß-catenin signaling were detected by qPCR, luciferase activity and Western blotting assays. The in vivo effect of GA on tumor growth was investigated using an orthotopic mouse model. Results: In the present study, GA was found to suppress the tumor growth in vitro via inducing cell cycle arrest and apoptosis in OS cells, and inhibit the invasion and metastasis as well. Using the orthotopic animal model, GA was also found to suppress tumorigenesis in vivo. Long noncoding RNA (lncRNA) H19 was demonstrated to be down-regulated by GA, and thus disrupted the canonical Wnt/ß-catenin signaling in OS cells. Furthermore, the ectopic expression of H19 rescued the GA-induced suppressive effects on tumor growth and metastasis, and partially reversed the inactivation of Wnt/ß-catenin signaling. Conclusions: Taken together, our results indicated that GA inhibited tumor growth through an H19-mediated Wnt/ß-catenin signaling regulatory axis in OS cells. The translational potential of this article: The information gained from this study provides a novel underlying mechanism of GA mediated anti-OS activity, suggesting that GA may be a promising drug candidate for OS patients.

19.
Heliyon ; 9(3): e14009, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36923879

RESUMO

Objective: To explore the mechanism of PG against acute lymphoblastic leukaemia (ALL) by network pharmacology and experimental verification in vitro. Methods: First, the biological activity of PG against B-ALL was determined by CCK-8 and flow cytometry. Then, the potential targets of PG were obtained from the PharmMapper database. ALL-related genes were collected from the GeneCards, OMIM and PharmGkb databases. The two datasets were intersected to obtain the target genes of PG in ALL. Then, protein interaction networks were constructed using the STRING database. The key targets were obtained by topological analysis of the network with Cytoscape 3.8.0 software. In addition, the mechanism of PG in ALL was confirmed by protein‒protein interaction, gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses. Furthermore, molecular docking was carried out by AutoDock Vina. Finally, Western blotting was performed to confirm the effect of PG on NALM6 cells. Results: PG inhibited the proliferation of NALM6 cells. A total of 174 antileukaemic targets of PG were obtained by network pharmacology. The key targets included AKT1, MAPK14, EGFR, ESR1, LCK, PTPN11, RHOA, IGF1, MDM2, HSP90AA1, HRAS, SRC and JAK2. Enrichment analysis found that PG had antileukaemic effects by regulating key targets such as MAPK signalling, and PG had good binding activity with MAPK14 protein (-8.9 kcal/mol). PG could upregulate the expression of the target protein p-P38, induce cell cycle arrest, and promote the apoptosis of leukaemia cells. Conclusion: MAPK14 was confirmed to be one of the key targets and pathways of PG by network pharmacology and molecular experiments.

20.
J Lab Physicians ; 14(1): 16-20, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36105911

RESUMO

Objective The von Willebrand disease (vWD) is one of the most common inherited bleeding disorders in India; however, the diagnostic tests and its interpretation require specialized laboratory and personnel which are not readily available in the eastern part of North India. The purpose of this study is to estimate the relative prevalence of vWD and study the clinical and laboratory features including advanced diagnostic tests. Methods All patients referred to the pathology department for evaluation of bleeding were evaluated for vWD during a period of 4 years. Clinical and laboratory features were analyzed and reported. Results A total of 1,126 cases of bleeding manifestations were evaluated, and 237 cases of inherited bleeding disorders were diagnosed; vWD was diagnosed in 38 (16%) of these 237 cases. Advanced diagnostic tests were done in all of these cases. Conclusion The vWD is among the most common inherited bleeding disorders in the country, second only to hemophilia A. Type-1 vWD was the most frequent with 25 cases (65.7%), followed by type-2N with 7 cases (18.4%).

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