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1.
J Mol Cell Cardiol ; 185: 1-12, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37839656

RESUMO

We recently described a subgroup of autopsied COVID-19 subjects (∼40%), termed 'profibrotic phenotype,' who exhibited clusters of myofibroblasts (Mfbs), which were positive for the collagen-specific chaperone heat shock protein 47 (HSP47+) in situ. This report identifies increased, localized (hot spot restricted) expression of αSMA, COLα1, POSTN and FAP supporting the identity of HSP47+ cells as myofibroblasts and characterizing a profibrotic extracellular matrix (ECM) phenotype. Coupled with increased GRP78 in COVID-19 subjects, these data could reflect induction of the unfolded protein response for mitigation of proteostasis (i.e., protein homeostasis) dysfunction in discrete clusters of cells. ECM shifts in selected COVID-19 subjects occur without significant increases in either global trichrome positive staining or myocardial injury based quantitively on standard H&E scoring. Our findings also suggest distinct mechanism(s) for ECM remodeling in the setting of SARS-CoV-2 infection. The ratio of CD163+/CD68+ cells is increased in hot spots of profibrotic hearts compared with either controls or outside of hot spots in COVID-19 subjects. In sum, matrix remodeling of human COVID-19 hearts in situ is characterized by site-restricted profibrotic mediated (e.g., HSP47+ Mfbs, CD163+ Mφs) modifications in ECM (i.e., COLα1, POSTN, FAP), with a strong correlation between COLα1 and HSP47+cells within hot spots. Given the established associations of viral infection (e.g., human immunodeficiency virus; HIV), myocardial fibrosis and sudden cardiac death, early screening tools (e.g., plasma biomarkers, noninvasive cardiac magnetic resonance imaging) for diagnosis, monitoring and treatment of fibrotic ECM remodeling are warranted for COVID-19 high-risk populations.


Assuntos
COVID-19 , Miofibroblastos , Humanos , Miofibroblastos/metabolismo , COVID-19/patologia , SARS-CoV-2 , Coração , Proteínas de Choque Térmico HSP47/genética , Proteínas de Choque Térmico HSP47/metabolismo , Fibrose
2.
Antioxidants (Basel) ; 12(8)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37627583

RESUMO

Doxorubicin (DOX), one of the most effective and widely used anticancer drugs, has the major limitation of cancer treatment-related cardiotoxicity (CTRTOX) in the clinic. Reactive oxygen species (ROS) generation and mitochondrial dysfunction are well-known consequences of DOX-induced injury to cardiomyocytes. This study aimed to explore the mitochondrial functional consequences and associated mechanisms of pretreatment with carvedilol, a ß-blocking agent known to exert protection against DOX toxicity. When disease modeling was performed using cultured rat cardiac muscle cells (H9c2 cells) and human iPSC-derived cardiomyocytes (iPSC-CMs), we found that prophylactic carvedilol mitigated not only the DOX-induced suppression of mitochondrial function but that the mitochondrial functional readout of carvedilol-pretreated cells mimicked the readout of cells overexpressing the major regulator of mitochondrial biogenesis, PGC-1α. Carvedilol pretreatment reduces mitochondrial oxidants, decreases cell death in both H9c2 cells and human iPSC-CM and maintains the cellular 'redox poise' as determined by sustained expression of the redox sensor Keap1 and prevention of DOX-induced Nrf2 nuclear translocation. These results indicate that, in addition to the already known ROS-scavenging effects, carvedilol has a hitherto unrecognized pro-reducing property against the oxidizing conditions induced by DOX treatment, the sequalae of DOX-induced mitochondrial dysfunction and compromised cell viability. The novel findings of our preclinical studies suggest future trial design of carvedilol prophylaxis, such as prescreening for redox state, might be an alternative strategy for preventing oxidative stress writ large in lieu of the current lack of clinical evidence for ROS-scavenging agents.

3.
Mol Biol Cell ; : mbcE21100527, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37585285

RESUMO

The LMNA gene encodes the nuclear envelope proteins Lamins A and C, which comprise a major part of the nuclear lamina, provide mechanical support to the nucleus, and participate in diverse intracellular signaling. LMNA mutations give rise to a collection of diseases called laminopathies, including dilated cardiomyopathy (LMNA-DCM) and muscular dystrophies. Although nuclear deformities are a hallmark of LMNA-DCM, the role of nuclear abnormalities in the pathogenesis of LMNA-DCM remains incompletely understood. Using induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) from LMNA mutant patients and healthy controls, we show that LMNA mutant iPSC-CM nuclei have altered shape or increased size compared to healthy control iPSC-CM nuclei. The LMNA mutation exhibiting the most severe nuclear deformities, R249Q, additionally caused reduced nuclear stiffness and increased nuclear fragility. Importantly, for all cell lines, the degree of nuclear abnormalities corresponded to the degree of Lamin A/C and Lamin B1 mislocalization from the nuclear envelope. The mislocalization was likely due to altered assembly of Lamin A/C. Collectively, these results point to the importance of correct lamin assembly at the nuclear envelope in providing mechanical stability to the nucleus and suggest that defects in nuclear lamina organization may contribute to the nuclear and cellular dysfunction in LMNA-DCM.

4.
J Am Heart Assoc ; 12(4): e027990, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36789856

RESUMO

Background Cardiac fibrosis complicates SARS-CoV-2 infections and has been linked to arrhythmic complications in survivors. Accordingly, we sought evidence of increased HSP47 (heat shock protein 47), a stress-inducible chaperone protein that regulates biosynthesis and secretion of procollagen in heart tissue, with the goal of elucidating molecular mechanisms underlying cardiac fibrosis in subjects with this viral infection. Methods and Results Using human autopsy tissue, immunofluorescence, and immunohistochemistry, we quantified Hsp47+ cells and collagen α 1(l) in hearts from people with SARS-CoV-2 infections. Because macrophages are also linked to inflammation, we measured CD163+ cells in the same tissues. We observed irregular groups of spindle-shaped HSP47+ and CD163+ cells as well as increased collagen α 1(I) deposition, each proximate to one another in "hot spots" of ≈40% of hearts after SARS-CoV-2 infection (HSP47+ P<0.05 versus nonfibrotics and P<0.001 versus controls). Because HSP47+ cells are consistent with myofibroblasts, subjects with hot spots are termed "profibrotic." The remaining 60% of subjects dying with COVID-19 without hot spots are referred to as "nonfibrotic." No control subject exhibited hot spots. Conclusions Colocalization of myofibroblasts, M2(CD163+) macrophages, and collagen α 1(l) may be the first evidence of a COVID-19-related "profibrotic phenotype" in human hearts in situ. The potential public health and diagnostic implications of these observations require follow-up to further define mechanisms of viral-mediated cardiac fibrosis.


Assuntos
COVID-19 , Miofibroblastos , Humanos , Miofibroblastos/metabolismo , SARS-CoV-2 , Colágeno/metabolismo , Proteínas de Choque Térmico/metabolismo , Colágeno Tipo I/metabolismo , Fenótipo , Macrófagos/metabolismo , Fibrose
5.
Redox Biol ; 48: 102196, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34872044

RESUMO

Mutations in the human LMNA gene cause a collection of diseases called laminopathies, which includes muscular dystrophy and dilated cardiomyopathy. The LMNA gene encodes lamins, filamentous proteins that form a meshwork on the inner side of the nuclear envelope. How mutant lamins cause muscle disease is not well understood, and treatment options are currently limited. To understand the pathological functions of mutant lamins so that therapies can be developed, we generated new Drosophila models and human iPS cell-derived cardiomyocytes. In the Drosophila models, muscle-specific expression of the mutant lamins caused nuclear envelope defects, cytoplasmic protein aggregation, activation of the Nrf2/Keap1 redox pathway, and reductive stress. These defects reduced larval motility and caused death at the pupal stage. Patient-derived cardiomyocytes expressing mutant lamins showed nuclear envelope deformations. The Drosophila models allowed for genetic and pharmacological manipulations at the organismal level. Genetic interventions to increase autophagy, decrease Nrf2/Keap1 signaling, or lower reducing equivalents partially suppressed the lethality caused by mutant lamins. Moreover, treatment of flies with pamoic acid, a compound that inhibits the NADPH-producing malic enzyme, partially suppressed lethality. Taken together, these studies have identified multiple new factors as potential therapeutic targets for LMNA-associated muscular dystrophy.

6.
Nat Commun ; 12(1): 6442, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34750360

RESUMO

The genetic architecture of atrial fibrillation (AF) encompasses low impact, common genetic variants and high impact, rare variants. Here, we characterize a high impact AF-susceptibility allele, KCNQ1 R231H, and describe its transcontinental geographic distribution and history. Induced pluripotent stem cell-derived cardiomyocytes procured from risk allele carriers exhibit abbreviated action potential duration, consistent with a gain-of-function effect. Using identity-by-descent (IBD) networks, we estimate the broad- and fine-scale population ancestry of risk allele carriers and their relatives. Analysis of ancestral migration routes reveals ancestors who inhabited Denmark in the 1700s, migrated to the Northeastern United States in the early 1800s, and traveled across the Midwest to arrive in Utah in the late 1800s. IBD/coalescent-based allele dating analysis reveals a relatively recent origin of the AF risk allele (~5000 years). Thus, our approach broadens the scope of study for disease susceptibility alleles to the context of human migration and ancestral origins.


Assuntos
Fibrilação Atrial/genética , Predisposição Genética para Doença/genética , Canal de Potássio KCNQ1/genética , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Potenciais de Ação , Alelos , Dinamarca , Emigrantes e Imigrantes , Feminino , Genótipo , Geografia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Linhagem , Fatores de Risco , Utah
7.
Cell Stress Chaperones ; 26(5): 859-868, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34382151

RESUMO

Vaccinations are widely credited with reducing death rates from COVID-19, but the underlying host-viral mechanisms/interactions for morbidity and mortality of SARS-CoV-2 infection remain poorly understood. Acute respiratory distress syndrome (ARDS) describes the severe lung injury, which is pathologically associated with alveolar damage, inflammation, non-cardiogenic edema, and hyaline membrane formation. Because proteostatic pathways play central roles in cellular protection, immune modulation, protein degradation, and tissue repair, we examined the pathological features for the unfolded protein response (UPR) using the surrogate biomarker glucose-regulated protein 78 (GRP78) and co-receptor for SARS-CoV-2. At autopsy, immunostaining of COVID-19 lungs showed highly elevated expression of GRP78 in both pneumocytes and macrophages compared with that of non-COVID control lungs. GRP78 expression was detected in both SARS-CoV-2-infected and un-infected pneumocytes as determined by multiplexed immunostaining for nucleocapsid protein. In macrophages, immunohistochemical staining for GRP78 from deceased COVID-19 patients was increased but overlapped with GRP78 expression taken from surgical resections of non-COVID-19 controls. In contrast, the robust in situ GRP78 immunostaining of pneumocytes from COVID-19 autopsies exhibited no overlap and was independent of age, race/ethnicity, and gender compared with that from non-COVID-19 controls. Our findings bring new insights for stress-response pathways involving the proteostatic network implicated for host resilience and suggest that targeting of GRP78 expression with existing therapeutics might afford an alternative therapeutic strategy to modulate host-viral interactions during SARS-CoV-2 infections.


Assuntos
Células Epiteliais Alveolares/metabolismo , COVID-19/metabolismo , Estresse do Retículo Endoplasmático , Proteínas de Choque Térmico/análise , Receptores de Coronavírus/análise , SARS-CoV-2/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , Autopsia , COVID-19/mortalidade , COVID-19/patologia , COVID-19/virologia , Estudos de Casos e Controles , Chaperona BiP do Retículo Endoplasmático , Feminino , Interações Hospedeiro-Patógeno , Humanos , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Masculino , Pessoa de Meia-Idade , Proteostase , Regulação para Cima , Adulto Jovem
8.
JCI Insight ; 4(22)2019 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-31723063

RESUMO

Mutations in B cell lymphoma 2-associated athanogene 3 (BAG3) are recurrently associated with dilated cardiomyopathy (DCM) and muscular dystrophy. Using isogenic genome-edited human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs), we examined how a DCM-causing BAG3 mutation (R477H), as well as complete loss of BAG3 (KO), impacts myofibrillar organization and chaperone networks. Although unchanged at baseline, fiber length and alignment declined markedly in R477H and KO iPSC-CMs following proteasome inhibition. RNA sequencing revealed extensive baseline changes in chaperone- and stress response protein-encoding genes, and protein levels of key BAG3 binding partners were perturbed. Molecular dynamics simulations of the BAG3-HSC70 complex predicted a partial disengagement by the R477H mutation. In line with this, BAG3-R477H bound less HSC70 than BAG3-WT in coimmunoprecipitation assays. Finally, myofibrillar disarray triggered by proteasome inhibition in R477H cells was mitigated by overexpression of the stress response protein heat shock factor 1 (HSF1). These studies reveal the importance of BAG3 in coordinating protein quality control subsystem usage within the cardiomyocyte and suggest that augmenting HSF1 activity might be beneficial as a means to mitigate proteostatic stress in the context of BAG3-associated DCM.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas Reguladoras de Apoptose , Cardiomiopatia Dilatada/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/química , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Cardiomiopatia Dilatada/metabolismo , Edição de Genes , Técnicas de Inativação de Genes , Proteínas de Choque Térmico HSC70/química , Proteínas de Choque Térmico HSC70/genética , Proteínas de Choque Térmico HSC70/metabolismo , Humanos , Simulação de Dinâmica Molecular , Mutação de Sentido Incorreto/genética
9.
Int J Environ Health Res ; 28(2): 159-166, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29564918

RESUMO

This study aims to assess the relationship between risk perception, attitude, and avoidance among residents toward an urban incinerator in Taichung, Taiwan. A cross-sectional study was conducted and three schools were enrolled. The case group was composed of 514 residents who live near an incinerator. The control group was composed of 264 people nearly the same age and who have lived in that area basically the same period of time. All participants were interviewed using a structured questionnaire. Results of this study showed that there was no significant difference between the exposure group and the control group in risk perception and attitude regarding the incinerator. However, the exposure group showed a significantly higher desire to move within one year or move sometime in the future than the control group. Therefore, these people should encourage the Environmental Protection Administration (EPA) to do everything it can to make sure that the incinerator operates safely.


Assuntos
Aprendizagem da Esquiva , Exposição Ambiental , Conhecimentos, Atitudes e Prática em Saúde , Incineração , Medição de Risco , Resíduos Sólidos , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Percepção , Taiwan
10.
Mol Med Rep ; 16(1): 639-646, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28560401

RESUMO

Recently, certain studies have demonstrated in vitro that prostaglandin E2 (PGE2) promotes human cluster of differentiation (CD)34+ cell homing. However, the sub­type receptors activated by PGE2 are unknown, as the PGE2 receptor EP1-4 subtypes (EP1-4) are expressed on the membrane of human CD34+ cells. Based on the above, the present study aimed to screen the receptor subtype activity by PGE2 to promote human CD34+ cell homing. It was observed that human CD34+ cells expressed the four PGE2 sub­receptors, particularly EP2 and 4. PGE2 increased EP2 and 4 mRNA expression significantly, while EP1 and 3 mRNA exhibited no significant alteration. PGE2, EP2 agonist (EP2A), and EP4A upregulated C­X­C chemokine receptor 4 mRNA and protein expression in human CD34+ cells, and promoted stromal cell­derived factor 1α (SDF­1α) expression in bone marrow mesenchymal stem cells (BMMSCs). These phenomena were inhibited by the associated receptor antagonists. PGE2, EP2A, and EP4A facilitated human CD34+ cell migration towards SDF­1α and BMMSCs. The results of the present study suggested that PGE2 promoted human CD34+ cell homing through EP2 and 4 receptors in vitro.


Assuntos
Antígenos CD34/metabolismo , Dinoprostona/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Receptores de Prostaglandina E Subtipo EP2/metabolismo , Receptores de Prostaglandina E Subtipo EP4/metabolismo , Biomarcadores , Movimento Celular , Células Cultivadas , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Dinoprostona/farmacologia , Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Fenótipo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Receptores de Prostaglandina E Subtipo EP2/genética , Receptores de Prostaglandina E Subtipo EP4/genética
11.
Stem Cell Reports ; 8(3): 491-499, 2017 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-28238794

RESUMO

Genome editing in induced pluripotent stem cells is currently hampered by the laborious and expensive nature of identifying homology-directed repair (HDR)-modified cells. We present an approach where isolation of cells bearing a selectable, HDR-mediated editing event at one locus enriches for HDR-mediated edits at additional loci. This strategy, called co-targeting with selection, improves the probability of isolating cells bearing HDR-mediated variants and accelerates the production of disease models.


Assuntos
Edição de Genes , Marcação de Genes , Genoma Humano , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Sistemas CRISPR-Cas , Linhagem Celular , Reparo do DNA por Junção de Extremidades , Técnicas de Introdução de Genes , Vetores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Células-Tronco Pluripotentes Induzidas/efeitos dos fármacos , Reparo de DNA por Recombinação
12.
Clin Chim Acta ; 468: 111-113, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28040556

RESUMO

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare and potentially fatal condition that can be primary or secondary. Secondary HLH due to Mycobacterium tuberculosis (TB) is uncommon. We report a case of tuberculosis-associated HLH in an umbilical cord blood transplant (UCBT) recipient and discuss its clinical characteristics and challenges. METHODS: Hematologic investigations, bone marrow aspirates, Xpert MTB/RIF test of TB with peripheral blood were performed. Immune modulation with anti-TB therapy was initiated. RESULTS: Subsequent treatment with anti-TB treatment resulted rapid clinical response and disease remission. CONCLUSION: It is important to consider TB as one of the underlying cause of HLH in high-risk patients, particularly those in immunodeficient states. Early diagnosis and treatment can improve the survival rates of patients with tuberculosis-associated HLH.


Assuntos
Sangue Fetal/transplante , Linfo-Histiocitose Hemofagocítica/complicações , Transplantados , Tuberculose/complicações , Adulto , Feminino , Humanos , Linfo-Histiocitose Hemofagocítica/sangue , Linfo-Histiocitose Hemofagocítica/diagnóstico , Linfo-Histiocitose Hemofagocítica/terapia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/fisiologia , Tuberculose/tratamento farmacológico
13.
J Biol Chem ; 291(29): 14939-53, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27226619

RESUMO

Mutations of HSPB5 (also known as CRYAB or αB-crystallin), a bona fide heat shock protein and molecular chaperone encoded by the HSPB5 (crystallin, alpha B) gene, are linked to multisystem disorders featuring variable combinations of cataracts, cardiomyopathy, and skeletal myopathy. This study aimed to investigate the pathological mechanisms involved in an early-onset myofibrillar myopathy manifesting in a child harboring a homozygous recessive mutation in HSPB5, 343delT. To study HSPB5 343delT protein dynamics, we utilize model cell culture systems including induced pluripotent stem cells derived from the 343delT patient (343delT/343delT) along with isogenic, heterozygous, gene-corrected control cells (WT KI/343delT) and BHK21 cells, a cell line lacking endogenous HSPB5 expression. 343delT/343delT and WT KI/343delT-induced pluripotent stem cell-derived skeletal myotubes and cardiomyocytes did not express detectable levels of 343delT protein, contributable to the extreme insolubility of the mutant protein. Overexpression of HSPB5 343delT resulted in insoluble mutant protein aggregates and induction of a cellular stress response. Co-expression of 343delT with WT prevented visible aggregation of 343delT and improved its solubility. Additionally, in vitro refolding of 343delT in the presence of WT rescued its solubility. We demonstrate an interaction between WT and 343delT both in vitro and within cells. These data support a loss-of-function model for the myopathy observed in the patient because the insoluble mutant would be unavailable to perform normal functions of HSPB5, although additional gain-of-function effects of the mutant protein cannot be excluded. Additionally, our data highlight the solubilization of 343delT by WT, concordant with the recessive inheritance of the disease and absence of symptoms in carrier individuals.


Assuntos
Cardiomiopatias/genética , Cardiomiopatias/metabolismo , Catarata/genética , Catarata/metabolismo , Doenças Musculares/genética , Doenças Musculares/metabolismo , Cadeia B de alfa-Cristalina/genética , Cadeia B de alfa-Cristalina/metabolismo , Cardiomiopatias/etiologia , Catarata/etiologia , Feminino , Homozigoto , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Masculino , Modelos Biológicos , Fibras Musculares Esqueléticas/metabolismo , Doenças Musculares/etiologia , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Miócitos Cardíacos/metabolismo , Linhagem , Agregação Patológica de Proteínas/genética , Agregação Patológica de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Deleção de Sequência , Solubilidade , Cadeia B de alfa-Cristalina/química
14.
Cell Physiol Biochem ; 38(4): 1288-302, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27008269

RESUMO

BACKGROUND/AIMS: Resistance of leukemia stem cells (LSCs) to chemotherapy in patients with acute myeloid leukemia (AML) causes relapse of disease. Hedgehog (Hh) signaling plays a critical role in the maintenance and differentiation of cancer stem cells. Yet its role in AML remains controversial. The purpose of the present study is to investigate the role of GLI1, the transcriptional activator of Hh signaling, in AML progenitor cells and to explore the anti-AML effects of GLI small-molecule inhibitor GANT61. METHODS: The expression of GLI1 mRNA and protein were examined in AML progenitor cells and normal cells. The proliferation, colony formation, apoptosis and differentiation of AML progenitor cells were also analyzed in the presence of GANT61. RESULTS: Kasumi-1 and KG1a cells, containing more CD34+ cells, expressed higher level of GLI1 compared to U937 and NB4 cells with fewer CD34+ cells. Consistently, a positive correlation between the protein levels of GLI1 and CD34 was validated in the bone marrow mononuclear cells (BMMC) of AML patients tested. GANT61 inhibited the proliferation and colony formation in AML cell lines. Importantly, GANT61 induced apoptosis in CD34+ enriched Kasumi-1 and KG1a cells, whereas it induced differentiation in U937 and NB4 cells. Furthermore, GANT61 enhanced the cytotoxicity of cytarabine (Ara-c) in primary CD34+ AML cells, indicating that inhibition of GLI1 could be a promising strategy to enhance chemosensitivity. CONCLUSIONS: The present findings suggested that Hh signaling was activated in AML progenitor cells. GLI1 acted as a potential target for AML therapy.


Assuntos
Antígenos CD34/metabolismo , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/metabolismo , Proteína GLI1 em Dedos de Zinco/antagonistas & inibidores , Proteína GLI1 em Dedos de Zinco/metabolismo , Adolescente , Adulto , Idoso , Apoptose/efeitos dos fármacos , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , Pessoa de Meia-Idade , Células-Tronco Neoplásicas/citologia , Piridinas/farmacologia , Pirimidinas/farmacologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Adulto Jovem , Proteína GLI1 em Dedos de Zinco/genética
15.
ACS Med Chem Lett ; 6(1): 63-7, 2015 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-25589932

RESUMO

Pim-1 has emerged as an attractive target for developing therapeutic agents for treating disorders involving abnormal cell growth, especially cancers. Herein we present lead optimization, chemical synthesis and biological evaluation of pyrazolo[1,5-a]pyrimidine compounds as potent and selective inhibitors of Pim-1 starting from a hit from virtual screening. These pyrazolo[1,5-a]pyrimidine compounds strongly inhibited Pim-1 and Flt-3 kinases. Selected compounds suppressed both the phosphorylation of BAD protein in a cell-based assay and 2-dimensional colony formation in a clonogenic cell survival assay at submicromolar potency, suggesting that cellular activity was mediated through inhibition of Pim-1. Moreover, these Pim-1 inhibitors did not show significant hERG inhibition at 30 µM concentration. The lead compound proved to be highly selective against a panel of 119 oncogenic kinases, indicating it had an improved safety profile compared with the first generation Pim-1 inhibitor SGI-1776.

16.
Am J Physiol Heart Circ Physiol ; 307(9): H1370-7, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25172899

RESUMO

Human induced pluripotent stem cell-derived cardiomyocyte (iPSC-CM)-based assays are emerging as a promising tool for the in vitro preclinical screening of QT interval-prolonging side effects of drugs in development. A major impediment to the widespread use of human iPSC-CM assays is the low throughput of the currently available electrophysiological tools. To test the precision and applicability of the near-infrared fluorescent voltage-sensitive dye 1-(4-sulfanatobutyl)-4-{ß[2-(di-n-butylamino)-6-naphthyl]butadienyl}quinolinium betaine (di-4-ANBDQBS) for moderate-throughput electrophysiological analyses, we compared simultaneous transmembrane voltage and optical action potential (AP) recordings in human iPSC-CM loaded with di-4-ANBDQBS. Optical AP recordings tracked transmembrane voltage with high precision, generating nearly identical values for AP duration (AP durations at 10%, 50%, and 90% repolarization). Human iPSC-CMs tolerated repeated laser exposure, with stable optical AP parameters recorded over a 30-min study period. Optical AP recordings appropriately tracked changes in repolarization induced by pharmacological manipulation. Finally, di-4-ANBDQBS allowed for moderate-throughput analyses, increasing throughput >10-fold over the traditional patch-clamp technique. We conclude that the voltage-sensitive dye di-4-ANBDQBS allows for high-precision optical AP measurements that markedly increase the throughput for electrophysiological characterization of human iPSC-CMs.


Assuntos
2-Naftilamina/análogos & derivados , Potenciais de Ação , Corantes Fluorescentes , Células-Tronco Pluripotentes Induzidas/fisiologia , Miócitos Cardíacos/fisiologia , Compostos de Quinolínio/química , Imagens com Corantes Sensíveis à Voltagem/métodos , 2-Naftilamina/química , Diferenciação Celular , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Raios Infravermelhos , Miócitos Cardíacos/citologia
17.
Stem Cell Reports ; 3(1): 131-41, 2014 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-25068127

RESUMO

Advances in induced pluripotent stem cell (iPSC) technology have set the stage for routine derivation of patient- and disease-specific human iPSC-cardiomyocyte (CM) models for preclinical drug screening and personalized medicine approaches. Peripheral blood mononuclear cells (PBMCs) are an advantageous source of somatic cells because they are easily obtained and readily amenable to transduction. Here, we report that the electrophysiological properties and pharmacological responses of PBMC-derived iPSC CM are generally similar to those of iPSC CM derived from other somatic cells, using patch-clamp, calcium transient, and multielectrode array (MEA) analyses. Distinct iPSC lines derived from a single patient display similar electrophysiological features and pharmacological responses. Finally, we demonstrate that human iPSC CMs undergo acute changes in calcium-handling properties and gene expression in response to rapid electrical stimulation, laying the foundation for an in-vitro-tachypacing model system for the study of human tachyarrhythmias.


Assuntos
Células-Tronco Pluripotentes Induzidas/citologia , Leucócitos Mononucleares/citologia , Miócitos Cardíacos/citologia , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Eletrofisiologia , Citometria de Fluxo , Humanos , Cariótipo
18.
Neoplasia ; 16(5): 403-12, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24953177

RESUMO

The proto-oncogene proviral integration site for moloney murine leukemia virus (PIM) kinases (PIM-1, PIM-2, and PIM-3) are serine/threonine kinases that are involved in a number of signaling pathways important to cancer cells. PIM kinases act in downstream effector functions as inhibitors of apoptosis and as positive regulators of G1-S phase progression through the cell cycle. PIM kinases are upregulated in multiple cancer indications, including lymphoma, leukemia, multiple myeloma, and prostate, gastric, and head and neck cancers. Overexpression of one or more PIM family members in patient tumors frequently correlates with poor prognosis. The aim of this investigation was to evaluate PIM expression in low- and high-grade urothelial carcinoma and to assess the role PIM function in disease progression and their potential to serve as molecular targets for therapy. One hundred thirty-seven cases of urothelial carcinoma were included in this study of surgical biopsy and resection specimens. High levels of expression of all three PIM family members were observed in both noninvasive and invasive urothelial carcinomas. The second-generation PIM inhibitor, TP-3654, displays submicromolar activity in pharmacodynamic biomarker modulation, cell proliferation studies, and colony formation assays using the UM-UC-3 bladder cancer cell line. TP-3654 displays favorable human ether-à-go-go-related gene and cytochrome P450 inhibition profiles compared with the first-generation PIM inhibitor, SGI-1776, and exhibits oral bioavailability. In vivo xenograft studies using a bladder cancer cell line show that PIM kinase inhibition can reduce tumor growth, suggesting that PIM kinase inhibitors may be active in human urothelial carcinomas.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células de Transição/enzimologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-pim-1/antagonistas & inibidores , Neoplasias da Bexiga Urinária/enzimologia , Animais , Western Blotting , Feminino , Humanos , Imidazóis/farmacologia , Masculino , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase Multiplex , Oligopeptídeos/farmacologia , Proto-Oncogene Mas , Piridazinas/farmacologia , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução Genética , Peptídeo Intestinal Vasoativo/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
20.
Yi Chuan ; 25(5): 549-51, 2003 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-15639927

RESUMO

The HLA-Cw loci polymorphism in Uygur population was investigated using the PCR- sequence specific oligonucleotide probe (SSOP) method,and the genetic database on the distribution of gene frequency of the HLA-Cw loci was established. From 146 individuals of Uygur population,18 HLA-Cw alleles were detected. The gene frequency was from 0.0069 to 0.2460. The four most common alleles were HLA-Cw*04(24.60%),07(11.51%),08(10 10%),14(12.02%),and they covered 58.23% of total alleles detected from Uygur population.We have made a survey of HLA-Cw alleles frequencies in a Uygur population,with blank frequency being lowered to 0.0064. The distribution of genotype frequencies met the law of Hardy-Weinberg equilibrium by hi-square test. The frequency data can be used in forensic and paternity tests to estimate the frequency of a DNA profile in the Uygur population,transplant matching and anthropology.

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