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1.
J Korean Med Sci ; 39(3): e32, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38258364

RESUMEN

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.


Asunto(s)
COVID-19 , Pandemias , Adolescente , Humanos , Intento de Suicidio , COVID-19/epidemiología , Factores de Riesgo , Emociones
2.
J Pharmacol Exp Ther ; 384(2): 277-286, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36410792

RESUMEN

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.


Asunto(s)
Síndrome del Intestino Corto , Animales , Humanos , Masculino , Ratones , Ratas , Péptido 2 Similar al Glucagón/farmacología , Absorción Intestinal , Intestino Delgado , Intestinos , Calidad de Vida , Síndrome del Intestino Corto/tratamiento farmacológico
3.
Neuroimage ; 264: 119748, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36370957

RESUMEN

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.


Asunto(s)
Estado de Conciencia , Tálamo , Humanos , Estado de Conciencia/fisiología , Tálamo/fisiología , Imagen por Resonancia Magnética , Percepción
4.
Anticancer Drugs ; 33(1): e370-e380, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34419957

RESUMEN

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.


Asunto(s)
Resistencia a Antineoplásicos/genética , Proteína 2 Similar a ELAV/genética , Proteína 4 Similar a ELAV/genética , Glucólisis/genética , Neoplasias Ováricas/genética , Antineoplásicos/farmacología , Caspasas/metabolismo , Línea Celular Tumoral , Femenino , Glucosa/metabolismo , Humanos , Ácido Láctico/metabolismo , Neoplasias Ováricas/patología , Paclitaxel/farmacología
5.
Bioorg Med Chem Lett ; 34: 127676, 2021 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-33166687

RESUMEN

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.


Asunto(s)
Antineoplásicos/farmacología , Diseño de Fármacos , Proteínas Inhibidoras de la Apoptosis/antagonistas & inhibidores , Quinazolinas/farmacología , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Perros , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Ratones , Estructura Molecular , Neoplasias Experimentales/tratamiento farmacológico , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Quinazolinas/síntesis química , Quinazolinas/química , Ratas , Relación Estructura-Actividad
6.
Biologicals ; 69: 49-58, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33277119

RESUMEN

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.


Asunto(s)
Factores de Crecimiento de Fibroblastos/uso terapéutico , Obesidad , Animales , Glucosa , Humanos , Fragmentos Fc de Inmunoglobulinas , Inmunoglobulina G , Ratones , Ratones Endogámicos ICR , Obesidad/tratamiento farmacológico , Proteínas Recombinantes
7.
Carcinogenesis ; 41(10): 1329-1340, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32649737

RESUMEN

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.


Asunto(s)
Neoplasias Colorrectales/metabolismo , Resistencia a Antineoplásicos , Transportador de Glucosa de Tipo 5/metabolismo , MicroARNs/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Antineoplásicos/farmacología , Movimiento Celular , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Regulación hacia Abajo , Activación Enzimática , Glucólisis/genética , Células HT29 , Humanos , Lipogénesis/genética , MicroARNs/genética , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/uso terapéutico , Receptores Toll-Like/metabolismo
8.
Hum Brain Mapp ; 41(11): 3119-3132, 2020 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-32250008

RESUMEN

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.


Asunto(s)
Cerebelo/fisiopatología , Corteza Cerebral/fisiopatología , Conectoma , Red Nerviosa/fisiopatología , Desempeño Psicomotor/fisiología , Trastornos Psicóticos/fisiopatología , Esquizofrenia/fisiopatología , Adulto , Cerebelo/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Red Nerviosa/diagnóstico por imagen , Equilibrio Postural/fisiología , Trastornos Psicóticos/diagnóstico por imagen , Esquizofrenia/diagnóstico por imagen , Corteza Sensoriomotora/diagnóstico por imagen , Corteza Sensoriomotora/fisiopatología , Adulto Joven
9.
Mol Carcinog ; 59(2): 154-167, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31746054

RESUMEN

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.


Asunto(s)
Antígenos CD/genética , Antígenos de Neoplasias/genética , Neoplasias Colorrectales/genética , Fluorouracilo/farmacología , Regulación Neoplásica de la Expresión Génica/genética , MicroARNs/genética , Receptores Toll-Like/genética , Antígenos CD/metabolismo , Antígenos de Neoplasias/metabolismo , Antimetabolitos Antineoplásicos/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Regulación hacia Abajo/efectos de los fármacos , Resistencia a Antineoplásicos/genética , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Células HT29 , Humanos , FN-kappa B/metabolismo , Interferencia de ARN , Receptores Toll-Like/metabolismo
10.
Toxicol Appl Pharmacol ; 402: 115126, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32645313

RESUMEN

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.


Asunto(s)
Eritropoyetina/análogos & derivados , Eritropoyetina/farmacología , Animales , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Eritropoyetina/administración & dosificación , Eritropoyetina/efectos adversos , Macaca fascicularis , Ratas , Ratas Sprague-Dawley
11.
Neuroimage ; 184: 409-416, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30237035

RESUMEN

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.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Conectoma , Red Nerviosa/crecimiento & desarrollo , Pobreza , Niño , Conectoma/métodos , Imagen de Difusión Tensora , Femenino , Humanos , Masculino , Caracteres Sexuales
12.
Hum Brain Mapp ; 40(1): 252-261, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30203892

RESUMEN

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.


Asunto(s)
Núcleo Caudado , Hipocampo , Abuso de Marihuana , Uso de la Marihuana , Red Nerviosa , Adulto , Núcleo Caudado/diagnóstico por imagen , Núcleo Caudado/patología , Núcleo Caudado/fisiopatología , Conectoma , Imagen de Difusión Tensora , Femenino , Hipocampo/diagnóstico por imagen , Hipocampo/patología , Hipocampo/fisiopatología , Humanos , Masculino , Abuso de Marihuana/diagnóstico por imagen , Abuso de Marihuana/patología , Abuso de Marihuana/fisiopatología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/patología , Red Nerviosa/fisiopatología , Adulto Joven
13.
Mar Drugs ; 17(7)2019 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-31336860

RESUMEN

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.


Asunto(s)
Muerte Celular Autofágica/efectos de los fármacos , Gliotoxina/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Línea Celular Tumoral , Proteínas Quinasas Asociadas a Muerte Celular/genética , Proteínas Quinasas Asociadas a Muerte Celular/metabolismo , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Silenciador del Gen , Gliotoxina/uso terapéutico , Humanos , Neoplasias Ováricas/patología , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , ARN Interferente Pequeño/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Regulación hacia Arriba/efectos de los fármacos
14.
Mar Drugs ; 17(9)2019 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-31505769

RESUMEN

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.


Asunto(s)
Antígenos CD34/metabolismo , Células Sanguíneas/efectos de los fármacos , Regulación hacia Abajo/efectos de los fármacos , Naftoquinonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Familia-src Quinasas/metabolismo , Antracenos/farmacología , Antioxidantes/metabolismo , Células Sanguíneas/metabolismo , Células Cultivadas , Células Madre Hematopoyéticas/efectos de los fármacos , Células Madre Hematopoyéticas/metabolismo , Humanos , Imidazoles/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Piridinas/farmacología , Células Madre/efectos de los fármacos , Células Madre/metabolismo
15.
Proc Natl Acad Sci U S A ; 113(3): 710-5, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26715758

RESUMEN

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.


Asunto(s)
Bioingeniería , Terapia Molecular Dirigida , Especificidad de Órganos , Saccharomyces cerevisiae/metabolismo , Vacuolas/metabolismo , Animales , Antineoplásicos/sangre , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Muerte Celular/efectos de los fármacos , Doxorrubicina/sangre , Doxorrubicina/farmacocinética , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Cinética , Ratones , Ratones Endogámicos C57BL , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Células RAW 264.7 , Receptor ErbB-2/metabolismo , Distribución Tisular/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
16.
Mol Cell Biochem ; 439(1-2): 199-211, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28819788

RESUMEN

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.


Asunto(s)
Proteína ADAM10/metabolismo , Proteína ADAM17/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Neoplasias del Colon/metabolismo , Transición Epitelial-Mesenquimal , Factor I del Crecimiento Similar a la Insulina/metabolismo , Lipogénesis , Proteínas de la Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Proteína ADAM10/genética , Proteína ADAM17/genética , Secretasas de la Proteína Precursora del Amiloide/genética , Fosfatidilinositol 3-Quinasa Clase I/genética , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Humanos , Factor I del Crecimiento Similar a la Insulina/genética , Proteínas de la Membrana/genética , Proteínas de Neoplasias/genética
17.
Cereb Cortex ; 27(11): 5230-5241, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27664961

RESUMEN

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.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Hidrocortisona/sangre , Efectos Tardíos de la Exposición Prenatal , Caracteres Sexuales , Encéfalo/diagnóstico por imagen , Niño , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/crecimiento & desarrollo , Embarazo , Problema de Conducta , Estudios Prospectivos
18.
Health Commun ; 33(8): 1013-1019, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-28622026

RESUMEN

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.


Asunto(s)
No Fumadores/estadística & datos numéricos , Etiquetado de Productos/métodos , Autoimagen , Autoeficacia , Fumadores/estadística & datos numéricos , Productos de Tabaco/efectos adversos , Adolescente , Adulto , Actitud Frente a la Salud , Femenino , Humanos , Intención , Masculino , Motivación , República de Corea , Cese del Hábito de Fumar/psicología , Prevención del Hábito de Fumar , Adulto Joven
19.
J Korean Med Sci ; 33(52): e347, 2018 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-30584419

RESUMEN

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.


Asunto(s)
Conducta Adictiva/patología , Padres/psicología , Teléfono Inteligente , Adolescente , Niño , Femenino , Humanos , Internet , Masculino , Psicología del Adolescente , Encuestas y Cuestionarios , Adulto Joven
20.
Mol Pharm ; 14(11): 3772-3779, 2017 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-28969419

RESUMEN

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.


Asunto(s)
Fibronectinas/metabolismo , Péptidos/metabolismo , Proteínas Recombinantes de Fusión/uso terapéutico , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Fibronectinas/química , Fibrosarcoma/tratamiento farmacológico , Melfalán/química , Melfalán/metabolismo , Ratones , Péptidos/química , Proteínas Recombinantes de Fusión/metabolismo , Factor de Necrosis Tumoral alfa/química
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