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1.
Ecotoxicol Environ Saf ; 280: 116516, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38820819

RESUMEN

The assessment of neurotoxicity for environmental chemicals is of utmost importance in ensuring public health and environmental safety. Multielectrode array (MEA) technology has emerged as a powerful tool for assessing disturbances in the electrophysiological activity. Although human embryonic stem cell (hESC)-derived neurons have been used in MEA for neurotoxicity screening, obtaining a substantial and sufficiently active population of neurons from hESCs remains challenging. In this study, we successfully differentiated neurons from a large population of human neuronal precursor cells (hNPC) purified using a polysialylated neural cell adhesion molecule (PSA-NCAM), referred to as hNPCPSA-NCAM+. The functional characterization demonstrated that hNPCPSA-NCAM+-derived neurons improve functionality by enhancing electrophysiological activity compared to total hNPC-derived neurons. Furthermore, three-dimensional (3D) neurons derived from hNPCPSA-NCAM+ exhibited reduced maturation time and enhanced electrophysiological activity on MEA. We employed subdivided population analysis of active mean firing rate (MFR) based on electrophysiological intensity to characterize the electrophysiological properties of hNPCPSA-NCAM+-3D neurons. Based on electrophysiological activity including MFR and burst parameters, we evaluated the sensitivity of hNPCPSA-NCAM+-3D neurons on MEA to screen both inhibitory and excitatory neuroactive environmental chemicals. Intriguingly, electrophysiologically active hNPCPSA-NCAM+-3D neurons demonstrated good sensitivity to evaluate neuroactive chemicals, particularly in discriminating excitatory chemicals. Our findings highlight the effectiveness of MEA approaches using hNPCPSA-NCAM+-3D neurons in the assessment of neurotoxicity associated with environmental chemicals. Furthermore, we emphasize the importance of selecting appropriate signal intensity thresholds to enhance neurotoxicity prediction and screening of environmental chemicals.


Asunto(s)
Fenómenos Electrofisiológicos , Contaminantes Ambientales , Células-Madre Neurales , Humanos , Células-Madre Neurales/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Fenómenos Electrofisiológicos/efectos de los fármacos , Neuronas/efectos de los fármacos , Ácidos Siálicos , Diferenciación Celular/efectos de los fármacos , Molécula L1 de Adhesión de Célula Nerviosa , Pruebas de Toxicidad/métodos
2.
Anal Chem ; 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34132523

RESUMEN

Human pluripotent stem cell (hPSC)-derived intestinal organoids (HIOs) hold unprecedented promise for basic biology and translational applications. However, developing a quantitative method to evaluate the epithelial cell membrane integrity of HIOs as an in vitro intestinal barrier model is a major challenge because of their complex three-dimensional (3D) structure. In this study, we developed an impedance system to measure the change in electrical resistance of 3D HIOs depending on the integrity of the intestinal epithelial cell membrane, which can reflect functionality and maturity. The expression of intestinal maturation- and tight junction-related markers was significantly higher in HIOs matured in vitro by treatment with IL-2 than in control HIOs. Analysis of gap junction size indicated that mature HIOs have greater integrity, with approximately 30% more compact gaps than immature HIOs. We designed a multi-microchannel system controlled by the inhalation pressure where the HIO is loaded, which enhances the stability and sensitivity of the impedance signal. We demonstrated the applicability of the impedance system by showing the difference in resistance between control and mature HIOs, reflecting the expression of tight junction proteins and their maturation status. We also validated the impedance system by monitoring its resistance in real time during junctional damage to HIOs induced by a digestive agent. In summary, we suggest a quantitative method to directly quantify the physiological changes in complex 3D organoid structures based on impedance spectroscopy, which can be applied to noninvasively monitor live cells and therefore enable their use in subsequent experiments.

3.
Int J Mol Sci ; 22(22)2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34830083

RESUMEN

Ifosfamide is an alkylating agent, a synthetic analogue of cyclophosphamide, used to treat various solid cancers. In this study, the toxicity of ifosfamide was evaluated using single-and multiple-dose intraperitoneal administration in rats under Good Laboratory Practice guidelines, and an additional microarray experiment was followed to support toxicological findings. A single dose of ifosfamide (50 mg/kg) did not induce any pathological changes. Meanwhile, severe renal toxicity was observed in the 7 and 28 days consecutively administered groups, with significant increases in blood urea nitrogen and creatinine levels. In the tox-list analysis, cholesterol synthesis-related genes were mostly affected in the liver and renal failure-related genes were affected in the kidney after ifosfamide administration. Moreover, interferon regulatory factor 7 was selected as the main upstream regulator that changed in both the liver and kidney, and was found to interact with other target genes, such as ubiquitin specific peptidase 18, radical S-adenosyl methionine domain containing 2, and interferon-stimulated gene 15, which was further confirmed by real-time RT-PCR analysis. In conclusion, we confirmed kidney-biased ifosfamide organ toxicity and identified identically altered genes in both the liver and kidney. Further comprehensive toxicogenomic studies are required to reveal the exact relationship between ifosfamide-induced genes and organ toxicity.


Asunto(s)
Enfermedad Hepática Inducida por Sustancias y Drogas , Regulación de la Expresión Génica/efectos de los fármacos , Ifosfamida/efectos adversos , Enfermedades Renales , Riñón , Hígado , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/metabolismo , Enfermedad Hepática Inducida por Sustancias y Drogas/patología , Ifosfamida/farmacología , Riñón/metabolismo , Riñón/patología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Hígado/metabolismo , Hígado/patología , Masculino , Ratas , Ratas Sprague-Dawley
4.
Breast Cancer Res Treat ; 173(2): 255-266, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30324273

RESUMEN

PURPOSE: The value of tumor-infiltrating lymphocytes (TILs) for prediction of pathologic complete response (pCR) in breast cancer (BC) patients treated with neoadjuvant chemotherapy (NAC) has received increasing attention. In human epidermal growth factor receptor 2 (HER2)-positive BC, advances in HER2-targeted therapy have not yet clarified the clinical implications of pre-NAC TILs. Likewise, the prognostic role of TILs for long-term survival is not well established. METHODS: Pre- and post-NAC TIL levels were evaluated in 248 pair-matched pre-NAC biopsy and post-NAC resection samples, and analyzed for predictive and prognostic significance with other clinicopathologic parameters. Additional 60 pre-NAC biopsy samples of HER2-positive BC treated with a TCHP regimen (docetaxel, carboplatin, and a combination of trastuzumab and pertuzumab) were also assessed. RESULTS: High pre-NAC TILs, clinical nodal stage 0-1 (cN0-1), and negative ER expression were shown to be strong predictive markers for pCR. A nomogram based on these significant clinicopathologic predictors was developed, providing integrated probability of achieving pCR after NAC. The association between high pre-NAC TIL levels and significantly increased pCR rate was also confirmed in HER2-positive BC patients treated with a TCHP regimen. After chemotherapy, increased quantity of post-NAC TILs was shown to have extended BC-specific survival and disease-free survival in univariable and multivariable analyses. CONCLUSIONS: High pre-NAC TIL levels were significantly predictive of pCR in BC, and can act as a surrogate marker for predicting therapeutic effects of a TCHP regimen for HER2-positive BC. Post-NAC TILs in residual disease were a new prognostic marker of risk stratification for long-term survival.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/terapia , Linfocitos Infiltrantes de Tumor/inmunología , Nomogramas , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Biopsia , Mama/patología , Mama/cirugía , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Mastectomía , Terapia Neoadyuvante/métodos , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/metabolismo
5.
Toxicol Mech Methods ; 29(7): 531-541, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31099283

RESUMEN

Ketoconazole (KTZ) and itraconazole (ITZ) are antifungal agents that have a broad spectrum of activity against fungal pathogens. However, the therapeutic indications of many antifungal drugs, including those of the azole group, are restricted due to possible hepatotoxicity. We performed toxicogenomic analyses using in vivo and in vitro models to investigate the molecular mechanisms underlying the hepatotoxicity of two azole antifungal drugs. C57BL/6 male mice were treated daily with KTZ or ITZ, sacrificed at days 1 or 7, and the serum biochemistry and histopathology results showed that the KTZ-treated mice exhibited hepatotoxicity. Primary hepatocytes from C57BL/6 mice also exposed to KTZ or ITZ, and the cytotoxic effects of KTZ and ITZ were evaluated; KTZ exerted a greater cytotoxic effect than ITZ. The gene expression profiles in the livers of the 7-day-treated group and primary hepatocytes of the 24-h-treated group for both KTZ and ITZ were comparatively analyzed. Differentially expressed genes were selected based on the fold-changes and statistical significance, and the biological functions were analyzed using ingenuity pathways analysis. The results revealed that genes related to cholesterol synthesis were overexpressed in the liver in the KTZ-treated group, whereas expression of those related to acute phase injury was significantly altered in the ITZ-treated group. Causal gene analyses suggested that sterol regulatory element-binding transcription factors are key regulators that activate the transcription of target genes associated with the hepatotoxicity induced by oral KTZ. These findings enhance our understanding of the molecular mechanisms underlying the hepatotoxicity of azole drugs.


Asunto(s)
Antifúngicos/toxicidad , Azoles/toxicidad , Hepatocitos/efectos de los fármacos , Hígado/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Animales , Supervivencia Celular/efectos de los fármacos , Perfilación de la Expresión Génica , Hepatocitos/metabolismo , Hepatocitos/patología , Itraconazol/toxicidad , Cetoconazol/toxicidad , Hígado/metabolismo , Hígado/patología , Masculino , Metabolómica , Ratones Endogámicos C57BL , Cultivo Primario de Células
6.
Breast Cancer Res Treat ; 160(3): 475-489, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27730423

RESUMEN

PURPOSE: Several pathologic classification systems have been developed to evaluate tumor response after neoadjuvant chemotherapy (NAC) for breast cancer. We aimed to compare pathologic classification systems and to investigate prognostic factors and risk stratification according to molecular subtype in relation to survival. METHODS: We retrospectively evaluated pathologic response after NAC in 485 breast cancer patients by applying the National Surgical Adjuvant Breast and Bowel Project B18 trial (NSABP-B18), Miller and Payne system, Chevallier's classification, Sataloff's classification, residual cancer burden (RCB), residual disease in breast and nodes (RDBN), and clinical-pathologic stage + estrogen receptor status and grade staging system (CPS + EG). RESULTS: All seven classification systems were significantly associated with overall survival (OS) and distant disease-free survival (DDFS). Regarding intrinsic subtypes, all systems were significantly associated with OS and DDFS for triple-negative tumors. Only RCB had prognostic significance for all four subtypes in relation to both OS and DDFS, and RDBN in DDFS only for all subtypes. In risk factor analyses, lymphovascular invasion (LVI), as well as other classic pathologic prognostic factors such as tumor size, lymph node status, and hormonal receptor status, was significantly associated with both OS and DDFS for the entire study group. Regarding subtypes, LVI was associated with DDFS for each subtype except Luminal B-like tumors. CONCLUSIONS: Our results suggest that pathologic classification systems that evaluate residual tumors in both breast and lymph nodes after NAC show better association with clinical outcome. Furthermore, combining LVI with other classic prognostic factors might have prognostic value for the assessment of treatment response after NAC.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/mortalidad , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor , Biopsia , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Persona de Mediana Edad , Imagen Multimodal/métodos , Terapia Neoadyuvante , Clasificación del Tumor , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento , Carga Tumoral
7.
Toxicol Appl Pharmacol ; 299: 8-23, 2016 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-26551752

RESUMEN

Given the rapid growth of engineered and customer products made of silver nanoparticles (Ag NPs), understanding their biological and toxicological effects on humans is critically important. The molecular developmental neurotoxic effects associated with exposure to Ag NPs were analyzed at the physiological and molecular levels, using an alternative cell model: human embryonic stem cell (hESC)-derived neural stem/progenitor cells (NPCs). In this study, the cytotoxic effects of Ag NPs (10-200µg/ml) were examined in these hESC-derived NPCs, which have a capacity for neurogenesis in vitro, at 6 and 24h. The results showed that Ag NPs evoked significant toxicity in hESC-derived NPCs at 24h in a dose-dependent manner. In addition, Ag NPs induced cell cycle arrest and apoptosis following a significant increase in oxidative stress in these cells. To further clarify the molecular mechanisms of the toxicological effects of Ag NPs at the transcriptional and post-transcriptional levels, the global expression profiles of genes and miRNAs were analyzed in hESC-derived NPCs after Ag NP exposure. The results showed that Ag NPs induced oxidative stress and dysfunctional neurogenesis at the molecular level in hESC-derived NPCs. Based on this hESC-derived neural cell model, these findings have increased our understanding of the molecular events underlying developmental neurotoxicity induced by Ag NPs in humans.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Células Madre Embrionarias Humanas/fisiología , Nanopartículas del Metal/toxicidad , MicroARNs/genética , Células-Madre Neurales/fisiología , Plata/toxicidad , Animales , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Estudios de Asociación Genética/métodos , Células Madre Embrionarias Humanas/efectos de los fármacos , Humanos , Ratones , Células-Madre Neurales/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
8.
Chemistry ; 20(10): 2895-900, 2014 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-24488727

RESUMEN

The hydroxyphenyl chiral ketone, (S)-3, reacts with D-amino acids bearing hydrophobic side chains exclusively over the L-amino acids in a two-phase liquid-liquid extraction, and thus acts as a highly stereoselective extractant. Calculations for the energy-minimized structures for the imine diastereomers and the comparison of the selectivities with other phenyl ketones, (S)-4 and (S)-5, demonstrate that the hydrogen bond between the carboxylate group and the phenolic hydroxyl group contributes to the remarkable enantioselectivities. The multiple hydrogen bonds present in the imine of (S)-3 reinforce the rigidity, and results in the difference between the stabilities of the imine diastereomers. The imine could be hydrolyzed in methanolic HCl solution, and the extraction of the evaporated residues revived the organic layer of (S)-3, which could enter into a new extractive cycle and leaves the D-amino acid with enantiomeric excess (ee) values of over 97 % in the aqueous layer.


Asunto(s)
Aminoácidos/química , Iminas/química , Cetonas/química , Naftoles/química , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Espectroscopía de Resonancia Magnética , Estructura Molecular , Estereoisomerismo
9.
J Appl Toxicol ; 34(6): 628-36, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23677851

RESUMEN

Nonylphenol (NP), a representative endocrine disruptor, interferes with reproductive function in aquatic organisms and animals. Although many previous studies have focused on apoptotic cell death by NP, the fundamental mechanism of NP on apoptosis remains poorly understood. Here, we investigated the molecular mechanism on NP-induced apoptotic cell death in mouse TM4 Sertoli cells. To evaluate NP treatment on cell viability, formazan and lactate dehydrogenase (LDH) assays were performed. Results indicate that NP reduced cell viability and increased the release of LDH in dose- and time-dependent manners. The reduction of cell viability by NP treatment appeared to involve necrosis as well as apoptosis based on nuclear fragmentation, an increase in the sub G1 population, and the detection of poly(ADP ribose) polymerase and caspase-3 cleavage. Additionally, the anti-apoptotic protein Bcl-2 diminished, whereas the pro-apoptotic protein Bax increased in a time-dependent manner. Note that NP-induced apoptotic cell death was enhanced by the generation of reactive oxygen species (ROS) and activation of extracellular signal-regulated kinase (ERK) signaling. Pretreatment with N-acetylcysteine, an antioxidant, attenuated NP-induced apoptotic cell death. Moreover, NP caused a transient activation of the MAPK pathway. In particular, NP-induced cell death was significantly suppressed by U0126, a specific inhibitor of ERK. Taken together, our results suggest that NP induces apoptosis in mouse TM4 Sertoli cells via ROS generation and ERK activation.


Asunto(s)
Apoptosis/efectos de los fármacos , Disruptores Endocrinos/toxicidad , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Estrés Oxidativo/efectos de los fármacos , Fenoles/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Células de Sertoli/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Antioxidantes/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Masculino , Ratones , Inhibidores de Proteínas Quinasas/farmacología , Células de Sertoli/enzimología , Células de Sertoli/patología , Factores de Tiempo
10.
Sci Rep ; 14(1): 4319, 2024 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-38383711

RESUMEN

In the field of drug discovery, natural products have emerged as therapeutic agents for diseases such as cancer. However, their potential toxicity poses significant obstacles in the developing effective drug candidates. To overcome this limitation, we propose a pathway-screening method based on imaging analysis to evaluate cellular stress caused by natural products. We have established a cellular stress sensing system, named Hepa-ToxMOA, which utilizes HepG2 cells expressing green fluorescent protein (GFP) fluorescence under the control of transcription factor response elements (TREs) for transcription factors (AP1, P53, Nrf2, and NF-κB). Additionally, to augment the drug metabolic activity of the HepG2 cell line, we evaluated the cytotoxicity of 40 natural products with and without S9 fraction-based metabolic activity. Our finding revealed different activities of Hepa-ToxMOA depending on metabolic or non-metabolic activity, highlighting the involvement of specific cellular stress pathways. Our results suggest that developing a Hepa-ToxMOA system based on activity of drug metabolizing enzyme provides crucial insights into the molecular mechanisms initiating cellular stress during liver toxicity screening for natural products. The pathway-screening method addresses challenges related to the potential toxicity of natural products, advancing their translation into viable therapeutic agents.


Asunto(s)
Regulación de la Expresión Génica , FN-kappa B , Humanos , FN-kappa B/metabolismo , Células Hep G2 , Proteínas Fluorescentes Verdes/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo
11.
Sci Rep ; 14(1): 5657, 2024 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-38454018

RESUMEN

Cerium oxide nanoparticles (CeO2 NPs, NM-212) are well-known for their catalytic properties and antioxidant potential, and have many applications in various industries, drug delivery, and cosmetic formulations. CeO2 NPs exhibit strong antimicrobial activity and can be used to efficiently remove pathogens from different environments. However, knowledge of the toxicological evaluation of CeO2 NPs is too limited to support their safe use. In this study, CeO2 NPs were orally administered to Sprague Dawley rats for 13 weeks at the doses of 0, 10, 100, and 1000 mg/kg bw/day, followed by a four week recovery period. The hematology values for the absolute and relative reticulocyte counts in male rats treated with 1000 mg/kg bw/day CeO2 NPs were lower than those in control rats. The clinical chemistry values for sodium and chloride in the treated male rat groups (100 and 1000 mg/kg/day) and total protein and calcium in the treated female rat groups (100 mg/kg/day) were higher than those in the control groups. However, these changes were not consistent in both sexes, and no abnormalities were found in the corresponding pathological findings. The results showed no adverse effects on any of the parameters assessed. CeO2 NPs accumulated in the jejunum, colon, and stomach wall of rats administered 1000 mg/kg CeO2 NPs for 90 days. However, these changes were not abnormal in the corresponding histopathological and immunohistochemical examinations. Therefore, 1000 mg/kg bw/day may be considered the "no observed adverse effect level" of CeO2 NPs (NM-212) in male and female SD rats under the present experimental conditions.


Asunto(s)
Cerio , Nanopartículas del Metal , Nanopartículas , Ratas , Masculino , Femenino , Animales , Ratas Sprague-Dawley , Nanopartículas/química , Cerio/toxicidad , Cerio/química , Sistemas de Liberación de Medicamentos , Nanopartículas del Metal/toxicidad , Nanopartículas del Metal/química
12.
J Am Chem Soc ; 135(7): 2653-8, 2013 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-23317343

RESUMEN

The chiral ketone (S)-3 shows high kinetic enantioselectivities toward the L form for general underivatized amino acids with hydrophobic side chains and a high thermodynamic enantioselectivity toward the D form for cysteine with its -SH polar side chain when used as an extractant in enantioselective liquid-liquid extractions in the presence of Aliquat 336. Consecutive extractions by imine formation and hydrolysis increase the enantiopurity of the amino acid, as both of these reactions are L-form-selective.


Asunto(s)
Aminoácidos/química , Cetonas/química , Teoría Cuántica , Cinética , Extracción Líquido-Líquido , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular , Estereoisomerismo , Termodinámica
13.
J Biochem Mol Toxicol ; 26(6): 213-23, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22711419

RESUMEN

Ethane dimethanesulfonate (EDS), a well-known alkylating agent, selectively destroys Leydig cells. To clarify the molecular pathways underlying EDS action on Leydig cells, we analyzed gene expression profiles of an EDS-treated TM3 Leydig cell line. In this study, we analyzed the representative canonical pathways and toxicity pathways/gene lists using the Ingenuity Pathways Analysis program. In TM3 cells, 677 and 6756 genes were identified as being up- or downregulated after 3 and 24 h EDS treatments, respectively, (>1.3-fold changes, p < 0.05). Toxicological pathway analysis revealed that expression of genes related to Nrf2-mediated oxidative stress response showed remarkable changes in early or later stage of EDS-treated TM3 cells. Several genes related to steroidogenesis and apoptosis were also differentially expressed at 24 h in EDS-treated TM3 cells. Overall, toxicological pathway analysis using gene expression profiling showed that oxidative stress might be an important factor in cell death in TM3 cells affected by EDS treatment.


Asunto(s)
Perfilación de la Expresión Génica , Células Intersticiales del Testículo/efectos de los fármacos , Mesilatos/toxicidad , Animales , Apoptosis/genética , Línea Celular , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Análisis de Secuencia por Matrices de Oligonucleótidos , Estrés Oxidativo , Esteroides/biosíntesis
14.
Exp Mol Med ; 54(9): 1461-1471, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36056186

RESUMEN

Mitochondria in neural progenitors play a crucial role in adult hippocampal neurogenesis by being involved in fate decisions for differentiation. However, the molecular mechanisms by which mitochondria are related to the genetic regulation of neuronal differentiation in neural progenitors are poorly understood. Here, we show that mitochondrial dysfunction induced by amyloid-beta (Aß) in neural progenitors inhibits neuronal differentiation but has no effect on the neural progenitor stage. In line with the phenotypes shown in Alzheimer's disease (AD) model mice, Aß-induced mitochondrial damage in neural progenitors results in deficits in adult hippocampal neurogenesis and cognitive function. Based on hippocampal proteome changes after mitochondrial damage in neural progenitors identified through proteomic analysis, we found that lysine demethylase 5A (KDM5A) in neural progenitors epigenetically suppresses differentiation in response to mitochondrial damage. Mitochondrial damage characteristically causes KDM5A degradation in neural progenitors. Since KDM5A also binds to and activates neuronal genes involved in the early stage of differentiation, functional inhibition of KDM5A consequently inhibits adult hippocampal neurogenesis. We suggest that mitochondria in neural progenitors serve as the checkpoint for neuronal differentiation via KDM5A. Our findings not only reveal a cell-type-specific role of mitochondria but also suggest a new role of KDM5A in neural progenitors as a mediator of retrograde signaling from mitochondria to the nucleus, reflecting the mitochondrial status.


Asunto(s)
Enfermedad de Alzheimer , Neuronas , Proteoma , Proteína 2 de Unión a Retinoblastoma/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Diferenciación Celular , Lisina/metabolismo , Ratones , Mitocondrias/metabolismo , Neuronas/citología , Neuronas/metabolismo , Proteoma/metabolismo , Proteómica
15.
Reprod Biol Endocrinol ; 9: 126, 2011 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-21914226

RESUMEN

BACKGROUND: It is known that some environmental chemicals affect the human endocrine system. The harmful effects of endocrine disrupting chemical (EDC) nonylphenol (NP) have been studied since the 1980s. It is known that NP adversely affects physiological functions by mimicking the natural hormone 17 beta-estradiol. In the present study, we analyzed the expression of miRNAs and their target genes in mouse Sertoli TM4 cells to better understand the regulatory roles of miRNAs on Sertoli cells after NP exposure. METHODS: Mouse TM4 Sertoli cells were treated with NP for 3 or 24 h, and global gene and miRNA expression were analyzed using Agilent mouse whole genome and mouse miRNA v13 arrays. RESULTS: We identified genes that were > 2-fold differentially expressed in NP-treated cells and control cells (P < 0.05) and analyzed their functions through Gene Ontology analysis. We also identified miRNAs that were differentially expressed in NP-treated and control cells. Of the 186 miRNAs the expression of which differed between NP-treated and control cells, 59 and 147 miRNAs exhibited 1.3-fold increased or decreased expression at 3 and 24 h, respectively. Network analysis of deregulated miRNAs suggested that Ppara may regulate the expression of certain miRNAs, including miR-378, miR-125a-3p miR-20a, miR-203, and miR-101a, after exposure to NP. Additionally, comprehensive analysis of predicted target genes for miRNAs showed that the expression of genes with roles in cell proliferation, the cell cycle, and cell death were regulated by miRNA in NP-treated TM4 cells. Levels of expression of the miRNAs miR-135a* and miR-199a-5p were validated by qRT-PCR. Finally, miR-135a* target gene analysis suggests that the generation of reactive oxygen species (ROS) following exposure to NP exposure may be mediated by miR-135a* through regulation of the Wnt/beta-catenin signaling pathway. CONCLUSIONS: Collectively, these data help to determine NP's actions on mouse TM4 Sertoli cells and increase our understanding of the molecular mechanisms underlying the adverse effects of xenoestrogens on the reproductive system.


Asunto(s)
Disruptores Endocrinos/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , MicroARNs/metabolismo , Fenoles/toxicidad , Células de Sertoli/efectos de los fármacos , Células de Sertoli/metabolismo , Animales , Ciclo Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Perfilación de la Expresión Génica , Masculino , Ratones , MicroARNs/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Concentración Osmolar , PPAR alfa/genética , PPAR alfa/metabolismo , ARN Mensajero/metabolismo , Células de Sertoli/patología , Factores de Tiempo
16.
Am J Trop Med Hyg ; 104(6): 1955-1959, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33891560

RESUMEN

World Malaria Day 2021 coincides with the 15th anniversary of the United States President's Malaria Initiative (PMI) and follows the first anniversary of the declaration of the coronavirus disease (COVID-19) pandemic. From 2006 to the present, the PMI has led to considerable country-managed progress in malaria prevention, care, and treatment in 24 of the highest-burden countries in sub-Saharan Africa and three countries in the Southeast Asia Greater Mekong subregion. Furthermore, it has contributed to a 29% reduction in malaria cases and a 60% reduction in the death rates in sub-Saharan Africa. In this context of progress, substantial heterogeneity persists within and between countries, such that malaria control programs can seek subnational elimination in some populations but others still experience substantial malaria disease and death. During the COVID-19 pandemic, most malaria programs have shown resilience in delivering prevention campaigns, but many experienced important disruptions in their care and treatment of malaria illness. Confronting the COVID-19 pandemic and building on the progress against malaria will require fortitude, including strengthening the quality and ensuring the safety and resiliency of the existing programs, extending services to those currently not reached, and supporting the people and partners closest to those in need.


Asunto(s)
COVID-19/epidemiología , Salud Global , Malaria/epidemiología , Malaria/prevención & control , Servicios Preventivos de Salud , SARS-CoV-2 , África del Sur del Sahara , Niño , Mortalidad del Niño , Humanos , Malaria/mortalidad , Control de Mosquitos , Estados Unidos , Organización Mundial de la Salud
17.
Nat Commun ; 12(1): 125, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33402682

RESUMEN

Scalable and economical methods for the production of optically pure amino acids, both natural and unnatural, are essential for their use as synthetic building blocks. Currently, enzymatic dynamic kinetic resolution (DKR) underpins some of the most effective processes. Here we report the development of enantioselective extraction coupled with racemization (EECR) for the chirality conversion of underivatized amino acids. In this process, the catalytic racemization of amino acids in a basic aqueous solution is coupled with the selective extraction of one enantiomer into an organic layer. Back-extraction from the organic layer to an acidic aqueous solution then completes the deracemization of the amino acid. The automation of the EECR process in a recycling flow reactor is also demonstrated. Continuous EECR is made possible by the sterically hindered chiral ketone extractant 5, which prevents the coextraction of the copper racemization catalyst because of its nonplanar geometry. Furthermore, the extractant 5 unexpectedly forms imines with amino acids faster and with greater enantioselectivity than less bulky derivatives, even though 5 cannot participate in intramolecular resonance-assisted hydrogen bonding. These features may allow EECR to challenge the preponderance of enzymatic DKR in the production of enantiomerically enriched amino acids.


Asunto(s)
Aminoácidos/química , Técnicas de Química Sintética , Iminas/química , Cetonas/química , Extracción Líquido-Líquido/métodos , Catálisis , Cobre/química , Cinética , Solventes/química , Estereoisomerismo
18.
Toxicol Lett ; 342: 73-84, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33609687

RESUMEN

Trovafloxacin (TVX) is associated with idiosyncratic drug-induced liver injury (iDILI) and inflammation-mediated hepatotoxicity. However, the inflammatory stress-regulated mechanisms in iDILI remain unclear. Herein, we elucidated the novel role of tumor-necrosis factor alpha (TNFα), an inflammatory stress factor, in TVX-induced in vitro hepatotoxicity and synergistic toxicity. TVX specifically induced synergistic toxicity in HepG2 cells with TNFα, which inhibits autophagy. TVX-treated HepG2 cells induced protective autophagy by inhibiting the expression of mTOR signaling proteins, while ATG5 knockdown in HepG2 cells, responsible for the impairment of autophagy, enhanced TVX-induced toxicity due to the increase in cytochrome C release and JNK pathway activation. Interestingly, the expression of mTOR signal proteins, which were suppressed by TVX, disrupted the negative feedback of the PI3K/AKT pathway and TNFα rebounded p70S6K phosphorylation. Co-treatment with TVX and TNFα inhibited protective autophagy by maintaining p70S6K activity, which enhanced TVX-induced cytotoxicity. Phosphorylation of p70S6K was inhibited by siRNA knockdown and rapamycin to restore TNFα-inhibited autophagy, which prevented the synergistic effect on TVX-induced cytotoxicity. These results indicate that TVX activates protective autophagy in HepG2 cells exposed to toxicity and an imbalance in negative feedback regulation of autophagy by TNFα synergistically enhanced the toxicity. The finding from this study may contribute to a better understanding of the mechanisms underlying iDILI associated with inflammatory stress.


Asunto(s)
Autofagia/efectos de los fármacos , Fluoroquinolonas/toxicidad , Hepatocitos/efectos de los fármacos , Naftiridinas/toxicidad , Factor de Necrosis Tumoral alfa/farmacología , Antimaláricos/toxicidad , Supervivencia Celular , Cloroquina/toxicidad , Regulación de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Humanos , Levofloxacino/farmacología , MAP Quinasa Quinasa 4/genética , MAP Quinasa Quinasa 4/metabolismo , Piperazinas/toxicidad , Proteínas Quinasas S6 Ribosómicas 70-kDa/genética , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Inhibidores de Captación de Serotonina y Norepinefrina/toxicidad , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Triazoles/toxicidad
19.
J Aging Health ; 32(9): 937-948, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31347451

RESUMEN

Objective: To examine the effect of access to outdoor space and buildings and social or community events on elders' perceived disconnectedness. Method: Data were from a representative survey conducted as part of an age-friendly community initiative in a large midwestern city in the United States. Hierarchical logistic regression was employed to examine the relationships between environment, engagement, and connection. Results: Having access to ramps to enter buildings reduced the odds of perceived disconnectedness by 79%, participation in social or community events reduced the odds of perceived disconnectedness by 83%. The odds of perceived disconnectedness for elders "not sure" of their access to public buildings were around 6 times that of those without access, holding all else constant. Discussion: Ensuring access to ramps to enter buildings, disseminating information about the accessibility of parks and buildings, and social or community events may reduce elders' perceived disconnectedness.


Asunto(s)
Entorno Construido/normas , Aislamiento Social/psicología , Participación Social/psicología , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ohio , Encuestas y Cuestionarios
20.
J Cerebrovasc Endovasc Neurosurg ; 21(3): 152-157, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31886150

RESUMEN

Stereotactic radiosurgery has become excellent alternative treatment for cerebral arteriovenous malformations (AVM). This technique has expanded to treatment of larger AVM which is not amenable to surgical management. However, its variable adverse effects should be also taken into considerations sincerely because of radiobiological characteristics such as delayed onset and progressive neurological deteriorations. Herein, we report a case in which progressively expanding hemorrhagic cyst with repeated bleedings so called chronic encapsulated expanding hematoma was developed on several years after radiosurgery treatment. Neurological and radiological findings were improved by surgical removal.

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