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1.
Vitae (Medellín) ; 29(3): 1-7, 2022-08-18. Ilustraciones
Artículo en Inglés | LILACS, COLNAL | ID: biblio-1393174

RESUMEN

Background: Hepatocellular carcinoma (HCC) is one of the most diagnosed cancers worldwide. Chemoprevention of HCC can be achieved using natural or synthetic compounds that reverse, suppress, detect, or prevent cancer progression. Objectives: In this study, both the antiproliferative effects and luminescent properties of 2'-hydroxychalcones were evaluated. Methods: Cell viability was evaluated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay, spectroscopy assays, and density functional theory (DFT) calculations were used to determine the luminescent properties of 2 ́-hydroxychalcones. Results: Cytotoxic effects of 2 ́-hydroxychalcones were observed over the HepG2 and EA.hy926 cells. Since the chalcone moiety could be used as a fluorescent probe, these compounds may be helpful in cancer diagnosis and tumor localization. They may enable tumor observation and regression through the fluorescence during treatment; therefore, the compounds are a potential candidate as novel anticancer agents acting on human hepatomas. Conclusions: This report describes the chalcones' use as a specific luminescent biomarker in tumor cells. We also report the cellular uptake of 2'-hydroxychalcones, their cellular distribution, and the mechanisms that may be responsible for their cytotoxic effects


ANTECEDENTES: El carcinoma hepatocelular (CHC) es uno de los cánceres más diagnosticados en todo el mundo. La quimio prevención del CHC se puede lograr utilizando compuestos naturales o sintéticos que reviertan, supriman, detecten o prevengan la progresión del cáncer. OBJETIVOS: En este estudio, se investigó tanto los efectos antiproliferativos como las propiedades luminiscentes de las 2'-hidroxicalconas. MÉTODOS: La viabilidad celular se evaluó usando el ensayo colorimétrico (MTT), los ensayos de espectroscopia y los cálculos DFT se usaron para determinar las propiedades luminiscentes de las 2 ́-hidroxichalconas. RESULTADOS: Se observaron efectos citotóxicos sobre las líneas celulares del tipo HepG2 y EA.hy926. Dado que la estructura de la 2 ́-hidroxichalcona puede ser usada como sonda fluorescente, estos compuestos pueden ser útiles en el diagnóstico del cáncer y la localización del tumor, ya que pueden permitir la observación a través de la fluorescencia y la regresión del tumor durante el tratamiento, por lo que son candidatas potenciales como nuevos agentes anticancerígenos que podrían actuar sobre hepatomas humanos. CONCLUSIONES: Este trabajo describe el uso de las 2 ́-hidroxichalconas como un biomarcador luminiscente específico para células tumorales. También informamos la captación celular de 2>-hidroxicalconas, su distribución celular y los mecanismos que pueden ser responsables de sus efectos citotóxicos


Asunto(s)
Humanos , Biomarcadores de Tumor , Supervivencia Celular/efectos de los fármacos , Chalconas/farmacología , Sustancias Luminiscentes , Antineoplásicos/farmacología , Células Hep G2/efectos de los fármacos
2.
Int. j. med. surg. sci. (Print) ; 9(2): 1-9, June 2022. ilus, graf
Artículo en Inglés | LILACS | ID: biblio-1512600

RESUMEN

Cisplatin, the first platinum compound approved for cancer treatment, is widely used in the treatment of various cancers including hepatocellular carcinoma (HCC). HCC incidence rates rise globally. Epithelial mesenchymal transition (EMT) is implicated in cancer invasion and metastasis, which are associated with increased mortality. Cisplatin dose might influence cancer invasion and metastatic behavior of the cells. The aim of the study was to investigate the effect of low-dose cisplatin treatment on EMT- related changes in HepG2 cells. Following treatment with 4 µM cisplatin, HepG2 cells were evaluated morphologically. Gene expression of E-cadherin, Vimentin, Snail1 was assessed by quantitative PCR. Immunofluorescence analyses of NA-K ATPase were performed. Although the low-dose cisplatin treated cells exhibited a more stretched morphology, no statistical difference was detected in gene expression of E-cadherin, Vimentin, Snail1 and immunofluorescence of NA-K ATPase. Findings on low-dose cisplatin effects in HepG2 might contribute to the knowledge of antineoplastic inefficacy by further understanding the molecular mechanisms of drug action.


El cisplatino, el primer compuesto de platino aprobado para el tratamiento del cáncer, es ampliamente utilizado en el tratamiento de varios tipos de cáncer, incluido el carcinoma hepatocelular (CHC). Las tasas de incidencia de CHC aumentan a nivel mundial. La transición mesenquimal epitelial (EMT) está implicada en la invasión del cáncer y la metástasis, que se asocian con un aumento de la mortalidad. La dosis de cisplatino podría influir en la invasión del cáncer y el comportamiento metastásico de las células. El objetivo del estudio fue investigar el efecto del tratamiento con dosis bajas de cisplatino en los cambios relacionados con la EMT en las células HepG2. Tras el tratamiento con cisplatino de 4 µM, se evaluaron morfológicamente las células HepG2. La expresión génica de E-cadherina, vimentina, caracol1 se evaluó mediante PCR cuantitativa. Se realizaron análisis de inmunofluorescencia de NA-K ATPasa . Aunque las células tratadas con cisplatino en dosis bajas exhibieron una morfología más estirada, no se detectaron diferencias estadísticas en la expresión génica de E-cadherina, vimentina, Snail1 e inmunofluorescencia de NA-K ATPasa. Los hallazgos sobre los efectos del cisplatino en dosis bajas en HepG2 podrían contribuir al conocimiento de la ineficacia antineoplásica al comprender mejor los mecanismos moleculares de la acción del fármaco.


Asunto(s)
Humanos , Cisplatino/administración & dosificación , Antineoplásicos/administración & dosificación , Vimentina/efectos de los fármacos , Vimentina/genética , Vimentina/metabolismo , Cadherinas/efectos de los fármacos , Cadherinas/genética , Cadherinas/metabolismo , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Microscopía Confocal , Células Hep G2 , Transición Epitelial-Mesenquimal , Reacción en Cadena en Tiempo Real de la Polimerasa , Factores de Transcripción de la Familia Snail/efectos de los fármacos , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo , Invasividad Neoplásica
3.
Bol. latinoam. Caribe plantas med. aromát ; 21(1): 108-122, ene. 2022. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1372494

RESUMEN

Cota tinctoria is a medicinal plant which has been used for management of cancer in folk medicine of various regions. The aim of present study is to investigate cytotoxic activity of different concentrations of hydroalcoholic extract of C. tinctoria flowers on gastric (AGS) and liver (Hep-G2) cancer cell lines as well as Human Natural GUM fibroblast (HUGU) cells. Cell mortality rates were examined after 24, 48 and 72 h incubations using the MTT assay. IC50of extract on AGS cells after 24, 48 and 72h was 1.46, 1.29 and 1.14 µg/mL respectively. The extract demonstrated IC50 of 5.15, 3.92 and 2.89 µg/mL on Hep-G2 cells after 24, 48 and 72 h respectively. No cytotoxic effect was detected on HUGU (Human Natural GUM fibroblast) cells. C. tinctoria seems to have a promising potential to be considered as a source for anticancer drug discovery. However, more experimental and clinical studies are required.


Cota tinctoria es una planta medicinal que se ha utilizado para el tratamiento del cáncer en la medicina popular de varias regiones. El objetivo del presente estudio es investigar la actividad citotóxica de diferentes concentraciones de extracto hidroalcohólico de flores de C. tinctoria en líneas celulares de cáncer gástrico (AGS) e hígado (Hep-G2), así como en células de fibroblasto GUM humano natural (HUGU). Se examinaron las tasas de mortalidad celular después de incubaciones de 24, 48 y 72 h utilizando el ensayo MTT. La CI50 del extracto en células AGS después de 24, 48 y 72 h fue de 1,46; 1,29 y 1,14 µg respectivamente. El extracto demostró una CI50 de 5,15, 3,92 y 2,89 µg/mL en células Hep-G2 después de 24, 48 y 72 h, respectivamente. No se detectó ningún efecto citotóxico en las células HUGU (fibroblasto GUM humano natural). C. tinctoria parece tener un potencial prometedor para ser considerada como una fuente de descubrimiento de fármacos contra el cáncer. Sin embargo, se requieren más estudios experimentales y clínicos.


Asunto(s)
Extractos Vegetales/administración & dosificación , Asteraceae/química , Línea Celular Tumoral/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Antineoplásicos Fitogénicos/administración & dosificación , Neoplasias Gástricas/tratamiento farmacológico , Flavonoides/análisis , Extractos Vegetales/farmacología , Extractos Vegetales/química , Técnicas de Cultivo de Célula , Anthemis/química , Compuestos Fenólicos/análisis , Células Hep G2/efectos de los fármacos , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química
4.
Braz. J. Pharm. Sci. (Online) ; 58: e19902, 2022. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1383970

RESUMEN

Abstract Xuezhikang (XZK) is an extract of Chinese red yeast rice. It has multiple protective effects in cardiovascular systems. However, the underlying mechanism by which XZK affects free fatty acid (FFA)-induced lipogenesis in hepatocellular steatosis model is still unknown. Herein, we investigated this mechanism in HepG2 cells. The HepG2 cells were treated with palmitate acid (PA) to induce lipogenesis. Then the PA-induced HepG2 cells were subsequently treated with XZK. After 24 h of treatment, we determined the intracellular triglyceride (TG) contents and average areas of lipid droplets. To study the involvement of AMPK signaling pathway, we pre-treated the PA-induced HepG2 cells with Compound C, an AMPK inhibitor, before XZK treatment. Expressions of p-AMPK and AMPK were determined by Western blot. The results showed that XZK decreased TG content and lipid accumulation in hepatocellular steatosis model. Compound C abolished the effects of XZK. These results demonstrated for the first time that XZK protects hepatocytes against lipid accumulation induced by free fatty acids. Its effects may be mediated by the activation of AMPK pathway.


Asunto(s)
Oryza/anatomía & histología , Quinasas de la Proteína-Quinasa Activada por el AMP/metabolismo , Lípidos/efectos adversos , Pueblo Asiatico/clasificación , Células Hep G2
5.
Journal of Southern Medical University ; (12): 518-527, 2022.
Artículo en Chino | WPRIM | ID: wpr-936343

RESUMEN

OBJECTIVE@#To explore the mechanism underlying the hepatoprotective effect of dihydromyricetin (DMY) against lipid accumulation in light of the lipophagy pathway and the inhibitory effect of DMY on HepG2 cell proliferation.@*METHODS@#LO2 cells were cultured in the presence of 10% FBS for 24 h and treated with 100 μg/mL DMY, or exposed to 50% FBS for 24 h followed by treatment with 50, 100, or 200 μg/mL DMY; the cells in recovery group were cultured in 50% FBS for 24 h and then in 10% FBS for another 24 h. Oil red O staining was used to observe the accumulation of lipid droplets in the cells, and the levels of TC, TG, and LDL and activities of AST, ALT and LDH were measured. The expression of LC3 protein was detected using Western blotting. AO staining and transmission electron microscopy were used to determine the numbers of autophagolysosomes and autophagosomes, respectively. The formation of autophagosomes was observed with MDC staining, and the mRNA expression levels of LC3, ATG7, AMPK, mTOR, p62 and Beclin1 were determined with q-PCR. Flow cytometry was performed to analyze the effect of 50, 100, and 200 μg/mL DMY on cell cycle and apoptosis of HepG2 cells; DNA integrity in the treated cells was examined with cell DNA fragmentation test.@*RESULTS@#DMY treatment and pretreatment obviously inhibited lipid accumulation and reduced the levels of TC, TG, LDL and enzyme activities of AST, ALT and LDH in LO2 cells (P < 0.05). In routinely cultured LO2 cells, DMY significantly promoted the formation of autophagosomes and autophagolysosomes and upregulated the expression of LC3 protein. DMY obviously attenuated high FBS-induced inhibition of autophagosome formation in LO2 cells, up- regulated the mRNA levels of LC3, ATG7, Beclin1 and AMPK, and downregulated p62 and mTOR mRNA levels (P < 0.05 or 0.01). In HepG2 cells, DMY caused obvious cell cycle arrest, inhibited cell proliferation, and induced late apoptosis and DNA fragmentation.@*CONCLUSION@#DMY reduces lipid accumulation in LO2 cells by regulating the AMPK/ mTOR-mediated lipophagy pathway and inhibits the proliferation of HepG2 by causing cell cycle arrest and promoting apoptosis.


Asunto(s)
Humanos , Proteínas Quinasas Activadas por AMP/metabolismo , Autofagia , Beclina-1 , Proliferación Celular , Flavonoles , Células Hep G2 , Lípidos , ARN Mensajero , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
6.
Braz. J. Pharm. Sci. (Online) ; 58: e201148, 2022. graf
Artículo en Inglés | LILACS | ID: biblio-1420444

RESUMEN

Abstract Hepatocellular carcinoma (HCC) is a common cause of cancer-related death. Sorafenib is the first approved drug for the treatment of advanced HCC. Depression is frequent in cancer patients. Moreover, sorafenib might exert depression as an adverse drug reaction and paroxetine, a selective serotonin reuptake inhibitor, is a recommended pharmacotherapy. This study aimed to investigate the potential synergistic effects of paroxetine and sorafenib on HepG2 cell proliferation and death. Paroxetine and sorafenib were administered to HepG2 cells as single-agents or in combination. Cell viability was determined with XTT cell viability assay. Cellular apoptosis and DNA content were assessed by flow cytometry. The expression of anti-apoptotic Bcl-2 was examined by immunofluorescence confocal microscopy. A lower dose of sorafenib was found to be required to inhibit cell proliferation when in combination with paroxetine. Similarly, the coadministration enhanced cellular apoptosis and resulted in cell cycle arrest. Confocal imaging revealed a remarkably lower cell density and increased expression of Bcl-2 following combined treatment of paroxetine with sorafenib. To our knowledge, this is the first study demonstrating the synergistic effect of paroxetine and sorafenib in HCC and might provide a potentially promising therapeutic strategy.


Asunto(s)
Paroxetina/efectos adversos , Células Hep G2/clasificación , Sorafenib/agonistas , Preparaciones Farmacéuticas/análisis , Carcinoma Hepatocelular/patología , Quimioterapia/instrumentación , Citometría de Flujo/métodos
7.
Int. j. med. surg. sci. (Print) ; 8(2): 1-12, jun. 2021. graf, ilus
Artículo en Inglés | LILACS | ID: biblio-1284445

RESUMEN

Background/aim: Autophagic cell death and apoptosis of tumor cells has become one of the main objectives in cancer treatment, whereas tumor cell lines are mainly used in studies for providing important data for the evaluation of potential anti cancer substances. In this study, our objective was to evaluate morphological and biochemical changes including rate of apoptosis and Alpha Fetoprotein (AFP) levels at different concentrations of Carnosic Acid (CA) on Human Hepatocellular Carcinoma HepG2 Cells.Materials and methods: Human Hepatocellular Carcinoma (7th passage HepG2 cells) Cell lines were cultured on 11 µM D263M schott glass coverslips placed in 12-well plates and were treated with DMSO, 1, 2.5, 5 and 10 µM concentrations of CA for 24, 48 and 72 hours. Morphological and biochemical data were recorded daily including apoptosis rates demonstrated by Caspase 3, Annexin V expressions under inverted light and Immunofluorescence microscopy, then data were analyzed for statistical significance. AFP, albumin and total protein levels were analyzed spectrophotometricaly for biochemical evaluation.Results: Our results showed that CA significantly inhibited HepG2 cell proliferation in a dose and time dependant manner and significantly caused the formation of autophagic vacuoles starting from 5µM and reaching significance at 10 µM concentrations. Significant decrease was observed in AFP when 48 and 72 hours expressions were examined, with the lowest level reached at 72 hours in the 10 µM CA group. Additionally, increase in albumin levels reached significance only in the 48 h group whereas non-significant increases were also observed in 24 h and 72 h groups.Conclusion: Our current study demonstrates significant increase in apoptosis rates by Carnosic Acid mainly at 10µM concentrations, supporting its anticancer effect on HepG2 cells. These findings are also supported by changes in biochemical analyses of Albumin and AFP levels at 10 µM concentrations.


Antecedentes / objetivos: La muerte celular autofágica y la apoptosis de células tumorales se ha convertido en uno de los principales objetivos en el tratamiento del cáncer, mientras que las líneas celulares tumorales se utilizan principalmente en estudios para proporcionar datos importantes para la evaluación de posibles sustancias anticancerígenas. En este estudio, nuestro objetivo fue evaluar los cambios morfológicos y bioquímicos, incluida la tasa de apoptosis y los niveles de alfa fetoproteína (AFP) a diferentes concentraciones de ácido carnósico (CA) en células de carcinoma hepatocelular humano HepG2.Materiales y métodos: Carcinoma hepatocelular humano (HepG2).Las líneas celulares se cultivaron en cubreobjetos de vidrio Schott D263M de 11 µM colocados en placas de 12 pocillos y se trataron con DMSO, concentraciones de CA 1, 2,5, 5 y 10 µM durante 24, 48 y 72 horas. Los datos morfológicos y bioquímicos se registraron diariamente, incluidas las tasas de apoptosis demostradas por Caspasa 3, las expresiones de Anexina V bajo luz invertida y microscopía de inmunofluorescencia, luego se analizaron los datos para determinar la significación estadística. Los niveles de AFP, albúmina y proteínas totales se analizaron espectrofotométricamente para evaluación bioquímica.Resultados: Nuestros resultados mostraron que CA inhibió significativamente la proliferación de células HepG2 de una manera dependiente de la dosis y el tiempo y causó significativamente la formación de vacuolas autofágicas comenzando desde 5 µM y alcanzando significancia a concentraciones de 10 µM. Se observó una disminución significativa en la AFP cuando se examinaron las expresiones de 48 y 72 horas, alcanzando el nivel más bajo a las 72 horas en el grupo de CA 10 µM. Además, el aumento en los niveles de albúmina alcanzó significación solo en el grupo de 48 h, mientras que también se observaron aumentos no significativos en los grupos de 24 hy 72 h.Conclusión: Nuestro estudio demuestra un aumento significativo en las tasas de apoptosis por el ácido carnósico principalmente a concentraciones de 10 µM, lo que respalda su efecto anticancerígeno en las células HepG2. Estos hallazgos también están respaldados por cambios en los análisis bioquímicos de los niveles de albúmina y AFP a concentraciones de 10 µM.


Asunto(s)
Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Abietanos/administración & dosificación , Células Hep G2/efectos de los fármacos , Neoplasias Hepáticas/tratamiento farmacológico , Supervivencia Celular , Células Cultivadas , Apoptosis/efectos de los fármacos , Microscopía Fluorescente
8.
Acta Academiae Medicinae Sinicae ; (6): 366-370, 2021.
Artículo en Chino | WPRIM | ID: wpr-887868

RESUMEN

Objective To observe the effect of cryptotanshinone on the ferroptosis of human liver cancer HepG2 cells. Methods The viability of the HepG2 cells cultured


Asunto(s)
Humanos , Ferroptosis , Células Hep G2 , Neoplasias Hepáticas , Fenantrenos/farmacología , Especies Reactivas de Oxígeno
9.
China Journal of Chinese Materia Medica ; (24): 2474-2480, 2021.
Artículo en Chino | WPRIM | ID: wpr-879150

RESUMEN

To explore the effect of light intensity in cultivating environment on the hepetoprotective activity of Sedum sarmentosum, S. sarmentosum were planted under five water treatments for 60 days, namely 100% full sunlight(G1), 77% full sunlight(G2), 60% full sunlight(G3), 38% full sunlight(G4), and 16% full sunlight(G5) and CCl_4 drug-induced liver injury model in vitro was used. Cell viability, cell cycle, and cell apoptosis were individually detected by MTT, PI single staining, and Annexin-V FITC/PI double staining assays. Additionally, ALT, AST and antioxidant index in supernatant were determined by colorimetry. And the relationship among the protective effects, chemical composition and antioxidant activity were also analyzed. The results showed that S. sarmentosum aqueous extract could significantly improve the HepG2 cell viability. Among the five S. sarmentosum groups, the cell viability of G1(100% full sunlight) treatment was the highest, and the cell apoptosis was the least. Meanwhile, the level of ALT, AST, and MDA in G1 was the lowest, but it achieved the highest level of SOD and GSH. Moderate light shading(60% full light) also improved the effect of protecting liver and reducing the enzyme. It was found that cell viability was positively correlated with ferricion reducing capacity. ALT activity was positively correlated with isorhamnetin content. Taken together, different light intensity had great influence on hepatoprotective effect of S. sarmentosum, which may be related to its antioxidant capacity. From the perspective of hepetoprotective activity, S. sarmentosum should be planted under full light.


Asunto(s)
Humanos , Antioxidantes , Enfermedad Hepática Inducida por Sustancias y Drogas , Células Hep G2 , Hígado , Extractos Vegetales/farmacología , Sedum , Agua
10.
Journal of Zhejiang University. Medical sciences ; (6): 582-590, 2021.
Artículo en Inglés | WPRIM | ID: wpr-922261

RESUMEN

To investigate the molecular mechanism of resveratrol inhibiting the metastasis of liver cancer . HepG2 and Huh7 cells were treated with different concentrations of resveratrol, and the cell viability was determined by CCK-8 assay to determine the optimal concentration of resveratrol for subsequent experiments. The expressions of miR-186-5p in liver cancer tissues and liver cancer cells were determined by quantitative real-time RT-PCR. The migration and invasion of HepG2 and Huh7 cells were detected by wound healing assay and Transwell assay, and the expression levels of epithelial-mesenchymal transition (EMT) related proteins were determined by Western blotting. Resveratrol with concentration of had no effect on the viability of HepG2 and Huh7 cells, so the concentration of resveratrol in subsequent experiments was 6.25 μmol/L. Resveratrol inhibited the wound healing and invasion of liver cancer cells; increased the expression of E-cadherin, and decreased the expression of vimentin and Twist1. The expression of miR-186-5p was significantly down-regulated in liver cancer tissues and cells compared with the adjacent tissues and normal liver cells (both <0.05). Furthermore, resveratrol induced the expression of miR-186-5p in liver cancer cells (both <0.01). Overexpression of miR-186-5p suppressed the migration, invasion and EMT of liver cancer cells. Knockdown of miR-186-5p blocked the inhibition effects of resveratrol on the migration, invasion and EMT of liver cancer cells. Resveratrol could inhibit the metastasis of liver cancer , which might be associated with up-regulating miR-186-5p.


Asunto(s)
Humanos , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Neoplasias Hepáticas/genética , MicroARNs/genética , Invasividad Neoplásica/genética , Resveratrol/farmacología
11.
Acta Physiologica Sinica ; (6): 813-820, 2021.
Artículo en Chino | WPRIM | ID: wpr-921284

RESUMEN

This study aimed to investigate the effect of lipopolysaccharide (LPS) on lipophagy in hepatocytes and the underlying mechanism. Human hepatoma cell line HepG2 was cultured in vitro, treated with 0.1 mmol/L palmitic acid (PA), and then divided into control group (0 μg/mL LPS), LPS group (10 μg/mL LPS), LPS+DMSO group and LPS+RAPA (rapamycin, 10 μmol/L) group. Lipid accumulation in hepatocytes was observed by oil red O staining. The autophagic flux of the cells was assessed using confocal laser scanning microscope after being transfected with autophagy double-labeled adenovirus (mRFP-GFP-LC3). The level of intracellular lipophagy was visualized by the colocalization of lipid droplets (BODIPY 493/503 staining) and lysosomes (lysosome marker, lysosomal associated membrane protein 1, LAMP1). The expression levels of mammalian target of rapamycin (mTOR), phosphorylated mTOR (p-mTOR), ribosome protein subunit 6 kinase 1 (S6K1), p-S6K1, LC3II/I and P62 protein were examined by Western blot. The results showed that the number of red lipid droplets stained with oil red O was significantly increased in LPS group compared with that in control group (P < 0.001). Moreover, in LPS group, the number of autophagosomes was increased, while the number of autophagolysosomes and the colocalization rate of LAMP1 and BODIPY were significantly decreased (P < 0.05). Meanwhile, the ratios of p-mTOR/mTOR and p-S6K1/S6K1, the ratio of LC3II/LC3I and the protein expression of P62 were significantly increased (P < 0.05) in LPS group. Furthermore, compared with LPS+DMSO group, RAPA treatment obviously reduced the number of lipid droplets and autophagosomes, and raised the number of autophagolysosomes and the colocalization rate of LAMP1 and BODIPY (P < 0.05). In conclusion, the results demonstrate that LPS inhibits lipophagy in HepG2 cells via activating mTOR signaling pathway, thereby aggravating intracellular lipid accumulation.


Asunto(s)
Humanos , Autofagia , Células Hep G2 , Lipopolisacáridos , Ácido Palmítico , Transducción de Señal , Serina-Treonina Quinasas TOR
12.
Journal of Peking University(Health Sciences) ; (6): 1107-1114, 2021.
Artículo en Chino | WPRIM | ID: wpr-942305

RESUMEN

OBJECTIVE@#To investigate evodiamine (EVO)-induced hepatotoxicity and the underlying mechanism.@*METHODS@#HepG2 cells were treated with EVO (0.04-25 μmol/L) for different time intervals, and the cell survival rate was examined by cell counting kit-8 (CCK-8) method. After HepG2 cells were treated with EVO (0.2, 1 and 5 μmol/L) for 48 h, the alanine transaminase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP) activities and total bilirubin (TBIL) content of supernatant were detected. A multifunctional microplate reader was used to detect the intracellular superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in HepG2 cells to evaluate the level of cell lipid peroxidation damage. The interactions between EVO and apoptosis, autophagy or ferroptosis-associated proteins were simulated by molecular docking. The HepG2 cells were stained by mitochondrial membrane potential (MMP) fluorescent probe (JC-10) and annexin V-fluorescein isothiocyanate/propidium iodide (Annexin V-FITC/PI), and MMP and apoptosis in HepG2 cells were detected by flow cytometry. The protein expression levels of caspase-9, caspase-3, bile salt export pump (BSEP) and multidrug resistance-associated protein 2 (MRP2) were detected by Western blot.@*RESULTS@#The cell survival rate was significantly reduced after the HepG2 cells were exposed to EVO (0.04-25 μmol/L) in a time- and dose-dependent manner. The half maximal inhibitory concentration (IC50) of the HepG2 cells treated with EVO for 24, 48 and 72 h were 85.3, 6.6 and 4.7 μmol/L, respectively. After exposure to EVO (0.2, 1 and 5 μmol/L) for 48 h, the ALT, AST, LDH, ALP activities and TBIL content in the HepG2 cell culture supernatant, and the MDA content in the cells were increased, and SOD enzyme activity was decreased. Molecular docking results showed that EVO interacted with apoptosis-associated proteins (caspase-9 and caspase-3) better. JC-10 and Annexin V-FITC/PI staining assays demonstrated that EVO could decrease MMP and promote apoptosis in the HepG2 cells. Western blot results indicated that the protein expressions of cleaved caspase-9 and cleaved caspase-3 were upregulated in the HepG2 cell treated with EVO for 48 h. In contrast, the protein expressions of pro-caspase-3, BSEP and MRP2 were downregulated.@*CONCLUSION@#These results suggested that 0.2, 1 and 5 μmol/L EVO had the potential hepatotoxicity, and the possible mechanism involved lipid peroxidation damage, cell apoptosis, and cholestasis.


Asunto(s)
Humanos , Miembro 11 de la Subfamilia B de Transportador de Casetes de Unión al ATP , Apoptosis , Caspasa 3 , Caspasa 9 , Colestasis , Células Hep G2/efectos de los fármacos , Peroxidación de Lípido , Hígado/efectos de los fármacos , Simulación del Acoplamiento Molecular , Proteína 2 Asociada a Resistencia a Múltiples Medicamentos , Quinazolinas/toxicidad
13.
Rev. chil. endocrinol. diabetes ; 14(1): 7-13, 2021. tab, ilus
Artículo en Español | LILACS | ID: biblio-1146465

RESUMEN

INTRODUCCIÓN: La enfermedad del hígado graso no alcohólico (EHGNA) es la forma más común de enfermedad hepática. A nivel celular se caracteriza por la acumulación de triglicéridos (TG) en forma de gotas lipídicas (GL) dando lugar a esteatosis e inflamación. Entre los factores relevantes para la síntesis de TG se encuentran las enzimas DGAT1/2 que catalizan la etapa final de la síntesis de TG, y la proteína FABP4 que transporta lípidos intracelulares y se expresa en modelos de enfermedad hepática dependiente de obesidad. Por otra parte, TNF-α es una reconocida citoquina involucrada en el proceso inflamatorio en la EHGNA. La medicina popular del norte de Chile ha utilizado la planta Lampaya medicinalis Phil. (Verbenaceae) para el tratamiento de algunas enfermedades inflamatorias. OBJETIVO: Evaluar el efecto de un extracto hidroalcóholico de lampaya (EHL) sobre la esteatosis y expresión de marcadores de inflamación en hepatocitos tratados con ácidos grasos. Diseño experimental: Estudio in vitro en cultivos de la línea celular humana HepG2 tratadas con ácido oleico (AO) y ácido palmítico (AP). MÉTODOS: Se incubó hepatocitos HepG2 con AO/AP por 24 horas en presencia o no de EHL. Se evaluó la presencia de GL y el contenido de TG intracelulares por Oil Red O y Nile Red, respectivamente. La expresión de DGAT1/2, FABP4 y TNF-α fue evaluada por qPCR. RESULTADOS: Los hepatocitos tratados con AO/AP mostraron un aumento en las GL y TG, así como una mayor expresión de DGAT2 en comparación al control. El cotratamiento con EHL revirtió los efectos inducidos por AO/AP. CONCLUSIONES: EHL revierte el incremento en las GL, TG y en la expresión de DGAT2 inducido por AO/AP en células HepG2. Estos hallazgos sugieren un efecto hepatoprotector de la Lampaya contra la esteatosis, y apoyarían su uso complementario en el tratamiento de patologías con componente inflamatorio como la EHGNA.


Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease. At the cellular level, it is characterized by the accumulation of triglycerides (TG) in the form of lipid droplets (LD), which leads to steatosis and inflammation. Among relevant factors for TG synthesis are the enzymes DGAT1/2 catalyzing the final stage of TG synthesis, and the protein FABP4 which transports intracellular lipids and is expressed in cell models of obesity-dependent liver disease. Additionally, TNF-α is a cytokine involved in the inflammatory process associated to NAFDL. Lampaya medicinalis Phil. (Verbenaceae) is a plant used in folk medicine in northern Chile to treat some inflammatory diseases. OBJECTIVE: To evaluate the effect of the hydroalcoholic extract of lampaya (HEL) on steatosis and the expression of inflammatory markers in hepatocytes treated with fatty acids. Study design: In vitro study in cultures of the human HepG2 cell line treated with oleic acid (OA) and palmitic acid (PA). METHODS: HepG2 hepatocytes were incubated with OA/PA for 24 hours in the presence and absence of HEL. The formation of LD and the accumulation of intracellular TG were assessed by Oil Red O and Nile Red, respectively. The expression of DGAT1/2, FABP4 and TNF-α was assessed by qPCR. RESULTS: The treatment with OA/PA increased the levels of LD and TG as well as the expression of DGAT2 in HepG2 hepatocytes compared to control cells. HEL cotreatment counteracted OA/PA-induced effects. CONCLUSIONS: HEL prevents the increase in LD and TG levels and DGAT2 expression induced by OA/PA in HepG2 cells. These findings suggest that lampaya may have a protective effect against hepatic steatosis, which would support its complementary use in the treatment of pathologies associated with inflammation, such as NAFLD.


Asunto(s)
Humanos , Extractos Vegetales/farmacología , Hepatocitos/efectos de los fármacos , Verbenaceae/química , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Triglicéridos/análisis , Técnicas In Vitro , Extractos Vegetales/uso terapéutico , Supervivencia Celular , Reacción en Cadena de la Polimerasa , Técnicas de Cultivo de Célula , Ácido Oléico , Etanol/química , Células Hep G2/efectos de los fármacos , Inflamación
14.
Appl. cancer res ; 40: 1-13, Oct. 19, 2020. ilus
Artículo en Inglés | LILACS, Inca | ID: biblio-1283485

RESUMEN

Background: Cell culture (spheroid and 2D monolayer cultures) is an essential tool in drug discovery. Piperlongumine (PLN), a naturally occurring alkaloid present in the long pepper (Piper longum), has been implicated in the regulation of GSTP1 activity. In vitro treatment of cancer cells with PLN increases ROS (reactive oxygen species) levels and induces cell death, but its molecular mode of action has not been entirely elucidated. Methods: In this study, we correlated the antiproliferative effects (2D and 3D cultures) of PLN (CAS 20069­09-4, Sigma-Aldrich) with morphological and molecular analyses in HepG2/C3A cell line. We performed assays for cytotoxicity (MTT), comet assays for genotoxicity, induction of apoptosis, analysis of the cell cycle phase, and analysis of the membrane integrity by flow cytometry. Relative expression of mRNA of genes related to proliferation, apoptosis, cell cycle control, metabolism of xenobiotics, and reticulum endoplasmic stress. Results: PLN reduced the cell proliferation by the cell cycle arrest in G2/M. Changes in the mRNA expression for CDKN1A (4.9x) and CCNA2 (0.5x) of cell cycle control genes were observed. Cell death occurred due to apoptosis, which may have been induced by increased expression of proapoptotic mRNAs (BAK1, 3.1x; BBC3, 2.4x), and by an increase in 9 and 3/7 active caspases. PLN induced cellular injury by ROS generation and DNA damage. DNA damage induced MDM2 signaling (3.0x) associated with the appearance of the monastral spindle in mitosis. Genes associated with ROS degradation also showed increased mRNA expression (GSR, 2.0x; SOD1, 2.1x). PLN induce endoplasmic reticulum stress with the increase in the mRNA expression of ERN1 (4.5x) and HSPA14 (2.2x). The xenobiotic metabolism showed increased mRNA expression for CYP1A2 (2.2x) and CYP3A4 (3.4x). In addition to 2D culture, PLN treatment also inhibited the growth of 3D culture (spheroids). Conclusion: Thus, the findings of our study show that several gene expression biomarkers (mRNAs) and monastral spindle formation indicated the many pathways of damage induced by PLN treatment that contributes to its antiproliferative effects


Asunto(s)
Humanos , ARN Mensajero/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Técnicas de Cultivo de Célula , Proliferación Celular/efectos de los fármacos , Dioxolanos/farmacología , Antineoplásicos/farmacología , Biomarcadores/análisis , Expresión Génica/efectos de los fármacos , Esferoides Celulares/efectos de los fármacos , Células Hep G2/efectos de los fármacos
15.
China Journal of Chinese Materia Medica ; (24): 6028-6035, 2020.
Artículo en Chino | WPRIM | ID: wpr-878866

RESUMEN

Epithelial-mesenchymal transformation(EMT) exists in embryonic development and is closely related to cell migration and invasion. The increased EMT level in tumors showed that E-cadherin was replaced by N-cadherin, and the expression of interstitial markers such as α-SMA and vimentin was up-regulated. It has been reported that lupeol can reduce the expression of matrix metalloproteinase-2(MMP-2), matrix metalloproteinase-9(MMP-9) and N-cadherin to inhibit the metastasis of osteoma cells. However lupeol has been less studied in liver cancer. Therefore, this paper investigated the effect of lupanol on invasion and metastasis of human hepatoma cell line HepG2 and SK-HEP-1 and its possible mechanism. MTT assay and Annexin V/PI double staining were used to investigate the effect of lupeol on activity and apoptosis of HepG2 cells and SK-HEP-1 cells. Moreover, the effect of lupeol on the invasion of HepG2 cells and SK-HEP-1 cells were evaluated by Transwell assay. The expressions of E-cadherin, N-cadherin, α-SMA, vimentin and MMP-9 were measured by Western blot. The model of subcutaneous transplantation of nude mice and the lung metastasis model of H22 hepatocellular carcinoma cells were established to evaluate the efficacy of lupeol in vivo on tumor growth and lung metastasis by HE staining combined with immunohistochemical assay. The results showed that lupeol inhibited the activity and invasion of HepG2 cells and SK-HEP-1 cells in a dose-dependent manner and induced apoptosis. Western blot showed that the expression of E-cadherin, a landmark protein for EMT, was induced by lupeol, and the expressions of N-cadherin, α-SMA, vimentin and MMP-9 were decreased. In vivo experiments showed that lupeol inhibited tumor growth in mice bearing xenograft. In addition, immunohistochemical experiments confirmed that lupeol could up-regulate the expression of E-cadherin in tumor tissues of nude mice, reduce the expression of N-cadherin, and inhibit the metastasis of liver cancer H22 cells in the lungs of mice. The above results indicated that the mechanism of lupeol inhibiting the invasion and metastasis of HCC cells may be related to the regulation of EMT process.


Asunto(s)
Animales , Humanos , Ratones , Carcinoma Hepatocelular , Línea Celular Tumoral , Movimiento Celular , Transición Epitelial-Mesenquimal , Regulación Neoplásica de la Expresión Génica , Células Hep G2 , Neoplasias Hepáticas , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones Desnudos , Invasividad Neoplásica , Triterpenos Pentacíclicos
16.
China Journal of Chinese Materia Medica ; (24): 2151-2157, 2020.
Artículo en Chino | WPRIM | ID: wpr-827968

RESUMEN

To investigate the inhibitory effects of two xanthone compounds, 1-hydroxy-2,3,4,8-4 methoxy xanthone(here in after referred to as Fr15) and 1-hydroxy-2,3,4,6-4 methoxy xanthone(here in after referred to as Fr17), on the proliferation of hepatocellular carcinoma cells HepG2, and to further investigate their mechanism in combination with transcriptomics. Cell counting was used to detect the effects of two kinds of xanthone compounds Fr15 and Fr17(0, 0.03, 0.15, 0.3 mmoL·L~(-1)) on the proliferation of HepG2 cells; the effects of the two compounds Fr15 and Fr17 on HepG2 cell cycle were detected by flow cytometry; the changes of autophagosomes count in cells were observed under fluorescence microscope; the expression of autophagy marker proteins autophagy marker proteins SQSTM 1(p62) and microtubule associated protein 1 light chain 3 Ⅰ/Ⅱ(LC3 Ⅰ/Ⅱ) in the cells was detected by Western blot; the differentially expressed genes between the control group and the experimental group were analyzed by RNA-seq transcriptome sequencing; qRT-PCR was used to verify the differentially expressed genes in sequencing. The results showed that compounds Fr15 and Fr17 inhibited the proliferation of HepG2 cells with the increase of drug concentration and time. Flow cytometry showed that compounds Fr15 and Fr17 had little effect on HepG2 cell cycle. Fluorescence microscopy results showed that the number of autophagosomes in cells increased with the increase of drug concentration. Western blot showed that the expression of p62 protein was decreased and the expression of LC3-Ⅱ protein was significantly increased after drug addition. The results of RNA sequencing showed that 26 102 and 52 351 differentially expressed genes were obtained in Fr15 and Fr17 respectively. Analysis of KEGG showed that drug treatment had a great effect on autophagy pathway. qRT-PCR verified that 6 up-regulated genes were related to autophagy, and their trend was consis-tent with sequencing results, where all 6 genes showed an up-regulated trend. Two xanthone compounds Fr15 and Fr17 may inhibit proliferation of HepG2 cells by inducing autophagy.


Asunto(s)
Apoptosis , Autofagia , Ciclo Celular , Células Hep G2 , Xantonas
17.
Acta Physiologica Sinica ; (6): 157-166, 2020.
Artículo en Chino | WPRIM | ID: wpr-827072

RESUMEN

This study was aimed to investigate the regulatory mechanism of heat shock protein 90 (Hsp90) on transcription factor EB (TFEB) during autophagy in liver cancer cells. Human hepatocellular carcinoma cell line HepG2 was treated with Hsp90 N- and C-terminal inhibitors (STA9090 and Novobiocin), respectively. Western blot and RT-PCR were used to detect the expression levels of TFEB and autophagy-related proteins. Chromatin immunoprecipitation (ChIP) assay was used to observe the ability of Hsp90α binding to the TFEB proximal promoter region. The double-luciferase gene reporter experiment was used to determine the activity of TFEB promoter. The results showed that hypoxia induced up-regulation of TFEB protein and mRNA expression levels in the HepG2 cells. The protein expression levels of TFEB, LC3 and P62 were down-regulated significantly by either STA9090 or Novobiocin, under both normoxic and hypoxic conditions. Transfection of Hsp90α-overexpressing plasmids up-regulated TFEB protein levels in either wild-type or Hsp90α knockout HepG2 cells. Hsp90 bound to the TFEB proximal promoter region and was involved in regulating TFEB transcriptional process. Whereas both STA9090 and Novobiocin inhibited Hsp90 to bind to the TFEB proximal promoter region, and decreased the activity of TFEB promoter. These results suggest that Hsp90 promotes TFEB transcription in human hepatocellular carcinoma cells by binding to the proximal promoter region, thereby up-regulating the expression levels of autophagy-related proteins.


Asunto(s)
Humanos , Autofagia , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice , Metabolismo , Carcinoma Hepatocelular , Metabolismo , Patología , Proteínas HSP90 de Choque Térmico , Metabolismo , Células Hep G2 , Neoplasias Hepáticas , Metabolismo , Patología , Regiones Promotoras Genéticas
18.
Chinese Journal of Biotechnology ; (12): 763-771, 2020.
Artículo en Chino | WPRIM | ID: wpr-826900

RESUMEN

The recombinant adenoviruses expressing miR-22 (Ad-miR-22) was constructed and the effect of Ad-miR-22 on insulin signal pathway and glucose uptake in HepG2 cells was analyzed. MiR-22 gene was amplified by PCR from human hepatocytes and cloned into the pAdTrack-CMV vector to generate the shuttle plasmid pAdT-22. The positive colonies were confirmed by PCR and sequencing. The resultant shuttle plasmid was linearized with Pme I, followed by co-transformation into competent BJ5183 cells containing an adenoviral backbone plasmid (pAdEasy-1) to create the recombinant plasmid pAd-miR-22. After digested with Pac I, the linearized pAd-miR-22 was transfected into 293A packaging cell line to generate recombinant adenoviruses Ad-miR-22. HepG2 cells were infected with Ad-miR-22 or control Ad-GFP (adenoviruses expressing green fluorescent protein), and then the miR-22 expression levels were analyzed by qPCR. The result shows that adenovirus-mediated overexpression of miR-22 significantly decreased insulin-induced glucose uptake in HepG2 cells. Moreover, overexpression of miR-22 markedly decreased insulin-induced phosphorylation of GSK-3β. miR-22 also increased the mRNA levels of gluconeogenic genes in HepG2 cells. Furthermore, Western blotting results indicate that the protein expression of SIRT1 decreased in Ad-miR-22 infected HepG2 cells as compared with Ad-GFP infected HepG2 cells. In summary, overexpressing of miR-22 significantly increased gluconeogenesis while decreased glucose uptake in HepG2 cells. The effect of miR-22 on glucose metabolism may be mediated by SIRT1.


Asunto(s)
Humanos , Adenoviridae , Genética , Glucosa , Metabolismo , Glucógeno Sintasa Quinasa 3 beta , Metabolismo , Células Hep G2 , MicroARNs , Genética , Metabolismo , Transducción de Señal , Genética , Transfección
19.
Adv Rheumatol ; 59: 28, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1088624

RESUMEN

Abstract Background: The V Brazilian Consensus for determination of autoantibodies against cellular constituents on HEp-2 cells, held in Brasilia (DF, Brazil) on August 27, 2016, discussed the harmonization between the Brazilian Consensus on ANA (BCA) guidelines and the International Consensus on ANA Patterns (ICAP) recommendations (www.anapatterns.org). Initial guidelines were formulated by the group of Brazilian experts with the purpose of guiding and enabling Brazilian clinical laboratories to adopt recommendations and to provide a common standard for national and international consensuses. Mainbody: Twenty Brazilian researchers and experts from universities and clinical laboratories representing the various geographical regions of the country participated in the meeting. Three main topics were discussed, namely the harmonization between the BCA guidelines and latest recommendations of the ICAP initiative, the adjustment of the terminology and report on HEp-2 patterns, and a reassessment of quality assurance parameters. For the three topics, our aim was to establish specific guidelines. All recommendations were based on consensus among participants. There was concrete progress in the adjustment of the BCA guidelines to match the ICAP guidelines. To a certain extent, this derives from the fact that ICAP recommendations were largely based on the algorithm and recommendations of the IV Brazilian ANA Consensus, as consistently recognized in the ICAP publications and presentations. However, although there is great overlap between the two Consensuses, there are some point divergences. These specific items were individually and extensively discussed, and it was acknowledged that in several points ICAP improved recommendations previously issued by the Brazilian ANA Consensus and these changes were readily implemented. Regarding some specific topics, the BCA panel of experts felt that the previously issued recommendations remained relevant and possibly will require further discussion with ICAP. The term anti-cell antibodies was adopted as the recommended designation, recognizing that the assay addresses antibodies against antigens in the nucleus and in other cell compartments. However, the acronym ANA HEp-2 was maintained due to historical and regulatory reasons. It was also signalized that the latest trend in ICAP is to adopt the term Indirect Immunofluorescent Assay on HEp-2 cell substrate (HEp-2 IIFA). In addition, the quality assurance strategies previously presented were ratified and emphasized. Conclusion: The V BCA edition was successful in establishing an overall harmonization with the ICAP recommendations for interpretation of the HEp-2 IIFA test, pinpointing the perspectives in filling the remaining gaps between both initiatives.


Asunto(s)
Autoanticuerpos/análisis , Células Hep G2 , Anticuerpos Antinucleares , Guías como Asunto/normas , Técnica del Anticuerpo Fluorescente Indirecta/instrumentación
20.
Journal of Nutrition and Health ; : 176-184, 2019.
Artículo en Inglés | WPRIM | ID: wpr-740562

RESUMEN

PURPOSE: Protein overloading in the endoplasmic reticulum (ER) leads to endoplasmic reticulum stress, which exacerbates various disease conditions. Emodin, an anthraquinone compound, is known to have several health benefits. The effect of emodin against palmitic acid (PA) - induced ER stress in HepG2 cells was investigated. METHODS: HepG2 cells were treated with varying concentrations of palmitic acid to determine the working concentration that induced ER stress. ER stress associated genes such as ATF4, XBP1s, CHOP and GRP78 were checked using RT- PCR. In addition, the expression levels of unfolded protein response (UPR) associated proteins such as IRE1α, eIF2α and CHOP were checked using immunoblotting to confirm the induction of ER stress. The effect of emodin on ER stress was analyzed by treating HepG2 cells with 750 µM palmitic acid and varying concentrations of emodin, then analyzing the expression of UPR associated genes. RESULTS: It was evident from the mRNA and protein expression results that palmitic acid significantly increased the expression of UPR associated genes and thereby induced ER stress. Subsequent treatment with emodin reduced the mRNA expression of ATF4, GRP78, and XBP1s. Furthermore, the protein levels of p-IRE1α, p-elF2α and CHOP were also reduced by the treatment of emodin. Analysis of sirtuin mRNA expression showed that emodin increased the levels of SIRT4 and SIRT7, indicating a possible role in decreasing the expression of UPR-related genes. CONCLUSION: Altogether, the results suggest that emodin could exert a protective effect against fatty acid-induced ER stress and could be an agent for the management of various ER stress related diseases.


Asunto(s)
Emodina , Estrés del Retículo Endoplásmico , Retículo Endoplásmico , Células Hep G2 , Immunoblotting , Beneficios del Seguro , Ácido Palmítico , Reacción en Cadena de la Polimerasa , ARN Mensajero , Sirtuinas , Respuesta de Proteína Desplegada
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