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1.
J Korean Med Sci ; 39(3): e32, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38258364

RESUMO

BACKGROUND: Understanding adolescents' mental health during the coronavirus disease 2019 (COVID-19) pandemic and identifying those most at risk is an urgent public health challenge. This study explored the trend of suicide attempts and the association between loneliness, family financial stress, and suicide attempts during the COVID-19 pandemic among adolescents. METHODS: Data of the 2020 to 2022 Korea Youth Risk Behavior Surveys for adolescents aged 13-18 years were used. Multivariate logistic regression analyses were performed to examine the association between suicide attempts, family financial stress, and loneliness during the COVID-19 pandemic. RESULTS: The trend of suicide attempt rates was lowest in 2020 (1.9%, 1,034 out of 53,534) and it showed an increasing trend with rates of 2.2% (1,159 out of 53,445) in 2021 and 2.5% (1,271 out of 50,455) in 2022. The risk of suicide attempt was higher among adolescents who experienced financial stress (in 2020: adjusted odds ratio [AOR], 1.53, 95% confidence interval [CI], 1.26-1.88; in 2021: AOR, 1.63, 95% CI, 1.03-1.54) and felt lonely (in 2020: AOR, 2.19, 95% CI, 1.78-2.70; in 2021: AOR, 2.65, 95% CI, 2.16-3.26; in 2022: AOR, 1.3, 95% CI, 1.04-1.55) than those who did not. CONCLUSION: The COVID-19 pandemic affected the suicide attempts of adolescents, with financial stress and feelings of loneliness closely linked to this impact. Although the pandemic nears its end, the persistent risk of suicide attempts among adolescents remains a concern. Therefore, it is imperative to implement targeted screening and interventions to address adolescent suicide risk.


Assuntos
COVID-19 , Pandemias , Adolescente , Humanos , Tentativa de Suicídio , COVID-19/epidemiologia , Fatores de Risco , Emoções
2.
J Pharmacol Exp Ther ; 384(2): 277-286, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36410792

RESUMO

Extensive bowel resection caused by various diseases that affect the intestines, such as Crohn's disease, volvulus, and cancer, leads to short bowel syndrome (SBS). Teduglutide is the only approved glucagon-like peptide-2 (GLP-2) drug for SBS; however, it requires daily administration. A novel GLP-2 analog with a prolonged duration of action to reduce dosing frequency and promote a greater efficacy may provide patients with a better quality of life. In the present study, the sustained exposure of HM15912 was characterized in normal male rats. The efficacy of HM15912 on intestinal growth and absorption capacity was also evaluated in normal male mice, rats, and SBS rats. HM15912 exhibited a remarkably extended half-life (42.3 hours) compared with teduglutide (0.6 hours) in rats. Despite somewhat lower in vitro potency on GLP-2 receptor than human GLP-2 or teduglutide, this longer-lasting mode of action promotes HM15912 to be more effective in terms of small intestinal growth than existing GLP-2 analogs even with a less frequent dosing interval of as little as once a week in rodents, including SBS rats. Furthermore, the small intestinal weight was approximately doubled, and the D-xylose absorption was significantly increased after pre-treatment of existing GLP-2 analogs on the market or under clinical development followed by HM15912 in rodents. These results indicate that HM15912 possesses a significant small bowel trophic effect driven by continuously increased exposure, supporting that HM15912 may be a novel treatment option with greater efficacy and the longest dosing interval among existing GLP-2 analogs for SBS with intestinal failure. SIGNIFICANCE STATEMENT: HM15912, a novel long-acting glucagon-like peptide-2 (GLP-2) analog, has a significant small bowel hypertrophic effect in rodents with a reduced frequency of administration compared to the existing GLP-2 analogs on the market or currently under clinical development. This study supports the possibility that HM15912 could be administered much less frequently than other long-acting GLP-2 analogs for patients with short bowel syndrome.


Assuntos
Síndrome do Intestino Curto , Animais , Humanos , Masculino , Camundongos , Ratos , Peptídeo 2 Semelhante ao Glucagon/farmacologia , Absorção Intestinal , Intestino Delgado , Intestinos , Qualidade de Vida , Síndrome do Intestino Curto/tratamento farmacológico
3.
Neuroimage ; 264: 119748, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370957

RESUMO

Although conscious perception is a fundamental cognitive function, its neural correlates remain unclear. It remains debatable whether thalamocortical interactions play a decisive role in conscious perception. To clarify this, we used functional magnetic resonance imaging (fMRI) where flickering red and green visual cues could be perceived either as a non-fused colour or fused colour. Here we show significantly differentiated fMRI neurodynamics only in higher-order thalamocortical regions, compared with first-order thalamocortical regions. Anticorrelated neurodynamic behaviours were observed between the visual stream network and default-mode network. Its dynamic causal modelling consistently provided compelling evidence for the involvement of higher-order thalamocortical iterative integration during conscious perception of fused colour, while inhibitory control was revealed during the non-fusion condition. Taken together with our recent magnetoencephalography study, our fMRI findings corroborate a thalamocortical inhibitory model for consciousness, where both thalamic inhibitory regulation and integrative signal iterations across higher-order thalamocortical regions are essential for conscious perception.


Assuntos
Estado de Consciência , Tálamo , Humanos , Estado de Consciência/fisiologia , Tálamo/fisiologia , Imageamento por Ressonância Magnética , Percepção
4.
Anticancer Drugs ; 33(1): e370-e380, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34419957

RESUMO

The dysregulation of glycolysis regardless of oxygen availability is one of the major characteristics of cancer cells. While the drug resistance of ovarian cancer cells has been extensively studied, the molecular mechanism of anticancer drug resistance under low-glucose conditions remains unknown. In this study, we investigated the pathway mediating drug resistance under low-glucose conditions by examining the relationship between embryonic lethal abnormal vision Drosophila homolog-like (ELAVL) protein and glycolysis-related enzymes. Ovarian cancer cells resistant to 2.5 nM paclitaxel were exposed to low-glucose media for 2 weeks, and the expression levels of ELAVL2, ELAVL4, glycolytic enzymes, and drug resistance-related proteins were elevated to levels comparable to those in cells resistant to 100 nM paclitaxel. Gene silencing of ELAVL2/4 using small interfering RNA prevented the upregulation of glycolysis-related enzymes, reduced lactate production, and sensitized 2.5 nM paclitaxel-resistant ovarian cancer cells to anticancer agents under hypoglycemic conditions. Furthermore, pharmacological inhibition of glycolytic enzymes with 2-deoxyglucose, a specific inhibitor of glycolysis, triggered caspase-dependent apoptosis, reduced lactate generation, and blocked the expression of drug resistance-related proteins under low-glucose conditions. These results suggest that the level of ELAVL2/4 is responsible for the development of chemoresistance through activation of the glycolysis pathway under glucose deprivation conditions.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Proteína Semelhante a ELAV 2/genética , Proteína Semelhante a ELAV 4/genética , Glicólise/genética , Neoplasias Ovarianas/genética , Antineoplásicos/farmacologia , Caspases/metabolismo , Linhagem Celular Tumoral , Feminino , Glucose/metabolismo , Humanos , Ácido Láctico/metabolismo , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia
5.
Bioorg Med Chem Lett ; 34: 127676, 2021 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-33166687

RESUMO

We recently reported the biological evaluations of monovalent IAP antagonist 7 with good potency (MDA-MB-231, IC50 = 19 nM). In an effort to increase cellular activity and improve favorable drug-like properties, we newly designed and synthesized bivalent analogues based on quinazoline structure of 7. Optimization of cellular potency and CYP inhibition led to the identification of 27, which showed dramatic increase of over 100-fold (IC50 = 0.14 nM) and caused substantial tumor regressions in MDA-MB-231 xenograft model. These results strongly support 27 as a promising bivalent antagonist for the development of an effective anti-tumor approaches.


Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Quinazolinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Camundongos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Quinazolinas/síntese química , Quinazolinas/química , Ratos , Relação Estrutura-Atividade
6.
Biologicals ; 69: 49-58, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33277119

RESUMO

FGF21 (Fibroblast Growth Factor 21), which is expressed in the liver, adipose tissue, and pancreas, has been widely known as a therapeutic candidate for metabolic diseases. Though FGF21 is crucial to glucose, lipid, and energy homeostasis, it is not straightforward to develop a new drug with FGF21 due to its short half-life in serum. Here, we derived a novel long-acting FGF21 (LAPS-FGF21), which is chemically conjugated to the human IgG4 Fc fragment for longer half-life in serum. The recombinant human IgG4 Fc fragment and FGF21 were prepared by the refolding of inclusion body and periplasmic expression in Escherichia coli overexpression systems, respectively. The efficacy study of LAPS-FGF21 in a Diet-Induced Obesity (DIO) mouse model revealed that LAPS-FGF21 reduced body weight effectively accompanied by improved glucose tolerance in a dose-dependent manner. The administration of LAPS-FGF21 also improved the blood profiles with a significant reduction in cholesterol and triglyceride levels. Additionally, the pharmacokinetic (PK) studies of LAPS-FGF21 using normal ICR mice demonstrated that the half-life of LAPS-FGF21 was approximately 64-fold longer than FGF21. Taken together, the LAPS-FGF21 could be a feasible drug candidate with excellent bodyweight loss efficacy and longer dosing interval by half-life increase in serum.


Assuntos
Fatores de Crescimento de Fibroblastos/uso terapêutico , Obesidade , Animais , Glucose , Humanos , Fragmentos Fc das Imunoglobulinas , Imunoglobulina G , Camundongos , Camundongos Endogâmicos ICR , Obesidade/tratamento farmacológico , Proteínas Recombinantes
7.
Carcinogenesis ; 41(10): 1329-1340, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32649737

RESUMO

In cancer, resistance to chemotherapy is one of the main reasons for therapeutic failure. Cells that survive after treatment with anticancer drugs undergo various changes, including in cell metabolism. In this study, we investigated the effects of AKT-mediated miR-125b-5p alteration on metabolic changes and examined how these molecules enhance migration and induce drug resistance in colon cancer cells. AKT1 and AKT3 activation in drug-resistant colon cancer cells caused aberrant downregulation of miR-125b-5p, leading to GLUT5 expression. Targeted inhibition of AKT1 and AKT3 restored miR-125b-5p expression and prevented glycolysis- and lipogenesis-related enzyme activation. In addition, restoring the level of miR-125b-5p by transfection with the mimic sequence not only significantly blocked the production of lactate and intracellular fatty acids but also suppressed the migration and invasion of chemoresistant colon cancer cells. GLUT5 silencing with small interfering RNA attenuated mesenchymal marker expression and migratory activity in drug-resistant colon cancer cells. Additionally, treatment with 2,5-anhydro-d-mannitol resensitized chemoresistant cancer cells to oxaliplatin and 5-fluorouracil. In conclusion, our findings suggest that changes in miR-125b-5p and GLUT5 expression after chemotherapy can serve as a new marker to indicate metabolic change-induced migration and drug resistance development.


Assuntos
Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Transportador de Glucose Tipo 5/metabolismo , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Antineoplásicos/farmacologia , Movimento Celular , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Regulação para Baixo , Ativação Enzimática , Glicólise/genética , Células HT29 , Humanos , Lipogênese/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/uso terapêutico , Receptores Toll-Like/metabolismo
8.
Hum Brain Mapp ; 41(11): 3119-3132, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32250008

RESUMO

Abnormalities of cerebellar function have been implicated in the pathophysiology of schizophrenia. Since the cerebellum has afferent and efferent projections to diverse brain regions, abnormalities in cerebellar lobules could affect functional connectivity with multiple functional systems in the brain. Prior studies, however, have not examined the relationship of individual cerebellar lobules with motor and nonmotor resting-state functional networks. We evaluated these relationships using resting-state fMRI in 30 patients with a schizophrenia-spectrum disorder and 37 healthy comparison participants. For connectivity analyses, the cerebellum was parcellated into 18 lobular and vermal regions, and functional connectivity of each lobule to 10 major functional networks in the cerebrum was evaluated. The relationship between functional connectivity measures and behavioral performance on sensorimotor tasks (i.e., finger-tapping and postural sway) was also examined. We found cerebellar-cortical hyperconnectivity in schizophrenia, which was predominantly associated with Crus I, Crus II, lobule IX, and lobule X. Specifically, abnormal cerebellar connectivity was found to the cerebral ventral attention, motor, and auditory networks. This cerebellar-cortical connectivity in the resting-state was differentially associated with sensorimotor task-based behavioral measures in schizophrenia and healthy comparison participants-that is, dissociation with motor network and association with nonmotor network in schizophrenia. These findings suggest that functional association between individual cerebellar lobules and the ventral attentional, motor, and auditory networks is particularly affected in schizophrenia. They are also consistent with dysconnectivity models of schizophrenia suggesting cerebellar contributions to a broad range of sensorimotor and cognitive operations.


Assuntos
Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Conectoma , Rede Nervosa/fisiopatologia , Desempenho Psicomotor/fisiologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Cerebelo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Rede Nervosa/diagnóstico por imagem , Equilíbrio Postural/fisiologia , Transtornos Psicóticos/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/fisiopatologia , Adulto Jovem
9.
Mol Carcinog ; 59(2): 154-167, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31746054

RESUMO

CD248, also called endosialin or tumor endothelial marker-1, is markedly upregulated in almost all cancers, including colon cancers. Changes in microRNA profiles are one of the direct causes of cancer development and progression. In this study, we investigated whether a change in CD248 expression in colon cancer cells could induce drug resistance after chemotherapy, and we explored the relationship between miR-125b-5p levels and CD248 expression in Toll-like receptor (TLR)-modified chemoresistant colon cancer cells. TLR2/6 and TLR5 upregulation in drug-resistant colon cancer cells contributed to miR-125b-5p downregulation and specificity protein 1 (Sp1)-mediated CD248 upregulation via nuclear factor-kappa B (NF-κB) activation. Exposure to specific TLR2/6 or TLR5 ligands enhanced the expression of mesenchymal markers as well as the migratory activity of oxaliplatin- or 5-fluorouracil-resistant colon cancer cells. The transfection of a synthetic miR-125b-5p mimic into chemoresistant cells prevented Sp1 and CD248 activation and significantly impaired invasive activity. Furthermore, Sp1 or CD248 gene silencing as well as miR-125b-5p overexpression markedly reversed drug resistance and inhibited epithelial-mesenchymal transition in colon cancer cells. Taken together, these results suggest that changes in miR-125b-5p levels play an important role in Sp1-mediated CD248 expression and the development of drug resistance in TLR-mutated colon cancer cells.


Assuntos
Antígenos CD/genética , Antígenos de Neoplasias/genética , Neoplasias Colorretais/genética , Fluoruracila/farmacologia , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/genética , Receptores Toll-Like/genética , Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , NF-kappa B/metabolismo , Interferência de RNA , Receptores Toll-Like/metabolismo
10.
Toxicol Appl Pharmacol ; 402: 115126, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32645313

RESUMO

Anemia is a frequent complication of chronic kidney disease (CKD) that causes an increase in morbidity and mortality and accelerates the rate of disease progression. Treatment with recombinant human erythropoietin (rhEPO) is a major breakthrough in the therapy of renal anemia. HM10760A, a long-acting EPO, has been developed as a treatment for anemia in CKD patients. A series of preclinical toxicology studies, such as acute, 4 week repeat-dose, and 13 week repeat-dose, was completed to support the safety of human exposure to HM10760A for up to 13 weeks. The rodent and non-rodent species used in the pivotal preclinical general toxicity studies were rats and monkeys, respectively. A once-a-week or once-every-two-week i.v dosing regimen was applied for 4 week and 13 week repeat-dose toxicity studies, respectively, in consideration of the expected administration frequency in humans. Based on the 13 week repeat-dose toxicity studies, 2.61 µg/kg and 22.03 µg/kg can be considered as the NOAELs (no observed adverse effect levels) in rats and monkeys, respectively. Almost all observations recorded at the low- and mid-dose levels are typical pharmacological effects of EPO and not uniquely attributed HM10760A toxicity. To account for the differences between human being and animal physiologies, the safety of HM10760A needs to be further confirmed in future clinical studies.


Assuntos
Eritropoetina/análogos & derivados , Eritropoetina/farmacologia , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Eritropoetina/administração & dosagem , Eritropoetina/efeitos adversos , Macaca fascicularis , Ratos , Ratos Sprague-Dawley
11.
Neuroimage ; 184: 409-416, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30237035

RESUMO

Socioeconomic disadvantage is associated with atypical development in specific brain regions, yet the relation between poverty and whole brain network organization (i.e., the connectome, a set of brain regions connected with neuronal pathways) has not been characterized. Developmental studies indicate that the connectome undergoes rapid change during childhood and is consequently likely to be highly sensitive to both salutary and detrimental influences. We investigated associations between the socioeconomic disparities measured by the income-to-needs ratio (INR) in childhood and structural brain network organization with 144 healthy children between 6 and 11 years of age (mean age = 8 years). INR of girls was positively and logarithmically associated with the extent to which brain networks were efficiently organized, suggesting that girls in more impoverished environments had less efficient brain network organization. Lower INR was associated with network inefficiency in multiple cortical regions including prefrontal cortex, cingulate, and insula, and in subcortical regions including the hippocampus and amygdala. These findings suggest that childhood poverty may result in wide-spread disruptions of the brain connectome among girls, particularly at the lowest INR levels, and are differentially expressed in females and males.


Assuntos
Encéfalo/crescimento & desenvolvimento , Conectoma , Rede Nervosa/crescimento & desenvolvimento , Pobreza , Criança , Conectoma/métodos , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Caracteres Sexuais
12.
Hum Brain Mapp ; 40(1): 252-261, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30203892

RESUMO

Cellular studies indicate that endocannabinoid type-1 retrograde signaling plays a major role in synaptic plasticity. Disruption of these processes by delta-9-tetrahydrocannabinol (THC) could produce alterations either in structural and functional brain connectivity or in their association in cannabis (CB) users. Graph theoretic structural and functional networks were generated with diffusion tensor imaging and resting-state functional imaging in 37 current CB users and 31 healthy non-users. The primary outcome measures were coupling between structural and functional connectivity, global network characteristics, association between the coupling and network properties, and measures of rich-club organization. Structural-functional (SC-FC) coupling was globally preserved showing a positive association in current CB users. However, the users had disrupted associations between SC-FC coupling and network topological characteristics, most perturbed for shorter connections implying region-specific disruption by CB use. Rich-club analysis revealed impaired SC-FC coupling in the hippocampus and caudate of users. This study provides evidence of the abnormal SC-FC association in CB users. The effect was predominant in shorter connections of the brain network, suggesting that the impact of CB use or predispositional factors may be most apparent in local interconnections. Notably, the hippocampus and caudate specifically showed aberrant structural and functional coupling. These structures have high CB1 receptor density and may also be associated with changes in learning and habit formation that occur with chronic cannabis use.


Assuntos
Núcleo Caudado , Hipocampo , Abuso de Maconha , Uso da Maconha , Rede Nervosa , Adulto , Núcleo Caudado/diagnóstico por imagem , Núcleo Caudado/patologia , Núcleo Caudado/fisiopatologia , Conectoma , Imagem de Tensor de Difusão , Feminino , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Masculino , Abuso de Maconha/diagnóstico por imagem , Abuso de Maconha/patologia , Abuso de Maconha/fisiopatologia , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Rede Nervosa/fisiopatologia , Adulto Jovem
13.
Mar Drugs ; 17(7)2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31336860

RESUMO

Death-associated protein kinase 1 (DAPK1) expression induced by diverse death stimuli mediates apoptotic activity in various cancers, including ovarian cancer. In addition, mutual interaction between the tumor suppressor p53 and DAPK1 influences survival and death in several cancer cell lines. However, the exact role and connection of DAPK1 and p53 family proteins (p53, p63, and p73) in drug-resistant ovarian cancer cells have not been studied previously. In this study, we investigated whether DAPK1 induction by gliotoxin derived from marine fungus regulates the level of transcriptionally active p63 (TAp63) to promote apoptosis in an autophagy-dependent manner. Pre-exposure of paclitaxel-resistant ovarian cancer cells to gliotoxin inhibited the expression of multidrug resistant-associated proteins (MDR1 and MRP1-3), disrupted the mitochondrial membrane potential, and induced caspase-dependent apoptosis through autophagy induction after subsequent treatment with paclitaxel. Gene silencing of DAPK1 prevented TAp63-mediated downregulation of MDR1 and MRP1-3 and autophagic cell death after sequential treatment with gliotoxin and then paclitaxel. However, pretreatment with 3-methyladenine (3-MA), an autophagy inhibitor, had no effect on the levels of DAPK1 and TAp63 or on the inhibition of MDR1 and MRP1-3. These results suggest that DAPK1-mediated TAp63 upregulation is one of the critical pathways that induce apoptosis in chemoresistant cancer cells.


Assuntos
Morte Celular Autofágica/efeitos dos fármacos , Gliotoxina/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Proteínas Quinases Associadas com Morte Celular/genética , Proteínas Quinases Associadas com Morte Celular/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica , Gliotoxina/uso terapêutico , Humanos , Neoplasias Ovarianas/patologia , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , RNA Interferente Pequeno/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Regulação para Cima/efeitos dos fármacos
14.
Mar Drugs ; 17(9)2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31505769

RESUMO

Intracellular reactive oxygen species (ROS) play an important role in the proliferation and differentiation of hematopoietic stem and progenitor cells (HSPCs). HSPCs are difficult to be expanded ex vivo while maintaining their stemness when they are exposed to oxidative damage after being released from the bone marrow. There have been efforts to overcome this limitation by using various cytokine cocktails and antioxidants. In this study, we investigated the effects of echinochrome A (Ech A)-a well-established and non-toxic antioxidant-on the ex vivo expansion of HSPCs by analyzing a CD34+ cell population and their biological functions. We observed that Ech A-induced suppression of ROS generation and p38-MAPK/JNK phosphorylation causes increased expansion of CD34+ cells. Moreover, p38-MAPK/JNK inhibitors SB203580 and SP600125 promoted ex vivo expansion of CD34+ cells. We also demonstrated that the activation of Lyn kinase and p110δ is a novel mechanism for Ech A to enhance ex vivo expansion of CD34+ cells. Ech A upregulated phospho-Src, phospho-Lyn, and p110δ expression. Furthermore, the Ech A-induced ex vivo expansion of CD34+ cells was inhibited by pretreatment with the Src family inhibitor PP1 and p110δ inhibitor CAL-101; PP1 blocked p110δ upregulation and PI3K/Akt activation, whereas CAL-101 and PI3K/Akt pathway inhibitor LY294002 did not block Src/Lyn activation. These results suggest that Ech A initially induces Src/Lyn activation, upregulates p110δ expression, and finally activates the PI3K/Akt pathway. CD34+ cells expanded in the presence of Ech A produced equal or more hematopoietic colony-forming cells than unexpanded CD34+ cells. In conclusion, Ech A promotes the ex vivo expansion of CD34+ cells through Src/Lyn-mediated p110δ expression, suppression of ROS generation, and p38-MAPK/JNK activation. Hence, Ech A is a potential candidate modality for the ex vivo, and possibly in vivo, expansion of CD34+ cells.


Assuntos
Antígenos CD34/metabolismo , Células Sanguíneas/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Naftoquinonas/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/metabolismo , Antracenos/farmacologia , Antioxidantes/metabolismo , Células Sanguíneas/metabolismo , Células Cultivadas , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imidazóis/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Piridinas/farmacologia , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
15.
Proc Natl Acad Sci U S A ; 113(3): 710-5, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26715758

RESUMO

Despite the appreciable success of synthetic nanomaterials for targeted cancer therapy in preclinical studies, technical challenges involving their large-scale, cost-effective production and intrinsic toxicity associated with the materials, as well as their inability to penetrate tumor tissues deeply, limit their clinical translation. Here, we describe biologically derived nanocarriers developed from a bioengineered yeast strain that may overcome such impediments. The budding yeast Saccharomyces cerevisiae was genetically engineered to produce nanosized vacuoles displaying human epidermal growth factor receptor 2 (HER2)-specific affibody for active targeting. These nanosized vacuoles efficiently loaded the anticancer drug doxorubicin (Dox) and were effectively endocytosed by cultured cancer cells. Their cancer-targeting ability, along with their unique endomembrane compositions, significantly enhanced drug penetration in multicellular cultures and improved drug distribution in a tumor xenograft. Furthermore, Dox-loaded vacuoles successfully prevented tumor growth without eliciting any prolonged immune responses. The current study provides a platform technology for generating cancer-specific, tissue-penetrating, safe, and scalable biological nanoparticles for targeted cancer therapy.


Assuntos
Bioengenharia , Terapia de Alvo Molecular , Especificidade de Órgãos , Saccharomyces cerevisiae/metabolismo , Vacúolos/metabolismo , Animais , Antineoplásicos/sangue , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Morte Celular/efeitos dos fármacos , Doxorrubicina/sangue , Doxorrubicina/farmacocinética , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/sangue , Neoplasias/tratamento farmacológico , Células RAW 264.7 , Receptor ErbB-2/metabolismo , Distribuição Tecidual/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Mol Cell Biochem ; 439(1-2): 199-211, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28819788

RESUMO

The activation of phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) is critical for the induction of epithelial-mesenchymal transition (EMT) by growth factors, including insulin-like growth factor 1 (IGF-1). The activation of intracellular lipogenesis provides proliferative and survival signals for cancer cells. In this study, we investigated the connection between lipogenesis-related EMT processes and IGF-1-mediated PI3K p110 isoform activation in primary (SW480 cells) and metastatic (SW620) colon carcinoma cells. We also examined the underlying signaling pathway that promotes fatty acid synthesis in IGF-1-activated colon cancer cells. IGF-1 stimulation upregulated the expression of lipogenic enzymes as well as the activation of Nardilysin (N-arginine dibasic convertase, NRD1) and its downstream targets, a disintegrin and metalloproteases 10 (ADAM10) and ADAM17. The upregulation of the Lyn/Syk-mediated PI3K p110δ isoform in SW480 cells and the Lyn-dependent PI3K p110α isoform in SW620 cells triggered fatty acid production and cell motility in IGF-1-activated colon cancer cells. Pharmacological inhibition with A66 (PI3K p110α specific inhibitor) and CAL-101 (PI3K p110δ specific inhibitor) efficiently inhibited EMT in colon cancer cells by blocking the NRD1/ADAM family protein signaling pathway. Gene silencing of NRD1 and ADAM family proteins attenuated the generation of intracellular fatty acid and the migratory activity of colon cancer cells. Our results suggest that the different isoforms of the PI3K p110 subunit could be therapeutic targets for primary and metastatic colon cancer and that regulation of the NRD1/ADAM signaling pathway controls lipogenesis-mediated EMT in IGF-1-stimulated colon cancer cells.


Assuntos
Proteína ADAM10/metabolismo , Proteína ADAM17/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias do Colo/metabolismo , Transição Epitelial-Mesenquimal , Fator de Crescimento Insulin-Like I/metabolismo , Lipogênese , Proteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína ADAM10/genética , Proteína ADAM17/genética , Secretases da Proteína Precursora do Amiloide/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Humanos , Fator de Crescimento Insulin-Like I/genética , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética
17.
Cereb Cortex ; 27(11): 5230-5241, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27664961

RESUMO

Elevated maternal cortisol concentrations have the potential to alter fetal development in a sex-specific manner. Female brains are known to show adaptive behavioral and anatomical flexibility in response to early-life exposure to cortisol, but it is not known how these sex-specific effects manifest at the whole-brain structural networks. A prospective longitudinal study of 49 mother child dyads was conducted with serial assessments of maternal cortisol levels from 15 to 37 gestational weeks. We modeled the structural network of typically developing children (aged 6-9 years) and examined its global connectome properties, rich-club organization, and modular architecture. Network segregation was susceptible only for girls to variations in exposure to maternal cortisol during pregnancy. Girls generated more connections than boys to maintain topologically capable and efficient neural circuits, and this increase in neural cost was associated with higher levels of internalizing problems. Maternal cortisol concentrations at 31 gestational weeks gestation were most strongly associated with altered neural connectivity in girls, suggesting a sensitive period for the maternal cortisol-offspring brain associations. Our data suggest that girls exhibit an adaptive response by increasing the neural network connectivity necessary for maintaining homeostasis and efficient brain function across the lifespan.


Assuntos
Encéfalo/crescimento & desenvolvimento , Hidrocortisona/sangue , Efeitos Tardios da Exposição Pré-Natal , Caracteres Sexuais , Encéfalo/diagnóstico por imagem , Criança , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/crescimento & desenvolvimento , Gravidez , Comportamento Problema , Estudos Prospectivos
18.
Health Commun ; 33(8): 1013-1019, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-28622026

RESUMO

Do graphic pictorial health warnings (GPHWs) on cigarette packaging work better for some people than others? According to the Extended Parallel Process Model (EPPM), fear appeals should heighten positive change only if a person believes he or she is capable of change (i.e., self-efficacy). We exposed 242 smokers and 241 nonsmokers (aged 18-29) in the Republic of Korea to either a GPHW or a text-only warning in a between-subjects experiment. Results indicated that the GPHW increased intentions and motivations to quit smoking (for smokers) and intentions and motivations to not start smoking (for nonsmokers). However, these effects were moderated by self-efficacy related to quitting or not starting smoking. For smokers, a GPHW was especially effective in increasing desires and intentions to quit for people high in self-efficacy and high in self-esteem. However, for nonsmokers, a GPHW was effective only when self-efficacy was high, regardless of self-esteem level. For smokers and nonsmokers, results were mediated by heightened perceived health estimation. Implications for understanding the effectiveness of warning labels on cigarettes, for the introduction of GPHWs in the Republic of Korea, and for the Extended Parallel Process Model, are discussed.


Assuntos
não Fumantes/estatística & dados numéricos , Rotulagem de Produtos/métodos , Autoimagem , Autoeficácia , Fumantes/estatística & dados numéricos , Produtos do Tabaco/efeitos adversos , Adolescente , Adulto , Atitude Frente a Saúde , Feminino , Humanos , Intenção , Masculino , Motivação , República da Coreia , Abandono do Hábito de Fumar/psicologia , Prevenção do Hábito de Fumar , Adulto Jovem
19.
J Korean Med Sci ; 33(52): e347, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30584419

RESUMO

BACKGROUND: Smartphone addiction has recently been highlighted as a major health issue among adolescents. In this study, we assessed the degree of agreement between adolescents' and parents' ratings of adolescents' smartphone addiction. Additionally, we evaluated the psychosocial factors associated with adolescents' and parents' ratings of adolescents' smartphone addiction. METHODS: In total, 158 adolescents aged 12-19 years and their parents participated in this study. The adolescents completed the Smartphone Addiction Scale (SAS) and the Isolated Peer Relationship Inventory (IPRI). Their parents also completed the SAS (about their adolescents), SAS-Short Version (SAS-SV; about themselves), Generalized Anxiety Disorder-7 (GAD-7), and Patient Health Questionnaire-9 (PHQ-9). We used the paired t-test, McNemar test, and Pearson's correlation analyses. RESULTS: Percentage of risk users was higher in parents' ratings of adolescents' smartphone addiction than ratings of adolescents themselves. There was disagreement between the SAS and SAS-parent report total scores and subscale scores on positive anticipation, withdrawal, and cyberspace-oriented relationship. SAS scores were positively associated with average minutes of weekday/holiday smartphone use and scores on the IPRI and father's GAD-7 and PHQ-9 scores. Additionally, SAS-parent report scores showed positive associations with average minutes of weekday/holiday smartphone use and each parent's SAS-SV, GAD-7, and PHQ-9 scores. CONCLUSION: The results suggest that clinicians need to consider both adolescents' and parents' reports when assessing adolescents' smartphone addiction, and be aware of the possibility of under- or overestimation. Our results cannot only be a reference in assessing adolescents' smartphone addiction, but also provide inspiration for future studies.


Assuntos
Comportamento Aditivo/patologia , Pais/psicologia , Smartphone , Adolescente , Criança , Feminino , Humanos , Internet , Masculino , Psicologia do Adolescente , Inquéritos e Questionários , Adulto Jovem
20.
Mol Pharm ; 14(11): 3772-3779, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28969419

RESUMO

Tumor necrosis factor-α has shown potent antitumor effects in preclinical and clinical studies. However, severe side effects at less than therapeutic doses have limited its systemic delivery, prompting the need for a new strategy for targeted delivery of the protein to tumors. Here, we report a fusion protein of mouse tumor necrosis factor (TNF)-α (mTNFα) and a cancer-targeting, high-affinity aptide and investigate its therapeutic efficacy in tumor-bearing mice. A fusion protein consisting of mTNFα, a linker, and an aptide specific to extra domain B (EDB) of fibronectin (APTEDB), designated mTNFα-APTEDB, was successfully produced by expression in Escherichia coli. mTNFα-APTEDB retained specificity and affinity for its target, EDB. In mice bearing EDB-overexpressing fibrosarcomas, mTNFα-APTEDB showed greater efficacy in inhibiting tumor growth than mTNFα alone or mTNFα linked to a nonrelevant aptide, without causing an appreciable loss in body weight. Moreover, in vivo antitumor efficacy was further significantly increased by combination treatment with the chemotherapeutic drug, melphalan, suggesting a synergistic effect attributable to enhanced drug uptake into the tumor as a result of TNFα-mediated enhanced vascular permeability. These results suggest that a fusion protein of mTNFα with a cancer-targeting peptide could be a new anticancer therapeutic option for ensuring potent antitumor efficacy after systemic delivery.


Assuntos
Fibronectinas/metabolismo , Peptídeos/metabolismo , Proteínas Recombinantes de Fusão/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Animais , Fibronectinas/química , Fibrossarcoma/tratamento farmacológico , Melfalan/química , Melfalan/metabolismo , Camundongos , Peptídeos/química , Proteínas Recombinantes de Fusão/metabolismo , Fator de Necrose Tumoral alfa/química
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