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1.
Sci Rep ; 7(1): 1728, 2017 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-28496142

RESUMEN

This study aimed to investigate the role of src-homology protein tyrosine phosphatase-1 (SHP-1)-signal transducer and activator of transcription 3 (STAT3) pathway in liver fibrogenesis and the anti-fibrotic effect of SHP-1 agonist. The antifibrotic activity of SC-43, a sorafenib derivative with an enhanced SHP-1 activity, was evaluated in two fibrosis mouse models by carbon tetrachloride induction and bile duct ligation. Rat, human, and primary mouse hepatic stellate cells (HSCs) were used for mechanistic investigations. The results showed that SHP-1 protein primarily localized in fibrotic areas of human and mouse livers. SC-43 treatment reduced the activated HSCs and thus effectively prevented and regressed liver fibrosis in both fibrosis mouse models and improved mouse survival. In vitro studies revealed that SC-43 promoted HSC apoptosis, increased the SHP-1 activity and inhibited phospho-STAT3. The enhanced SHP-1 activity in HSCs significantly inhibited HSC proliferation, whereas SHP-1 inhibition rescued SC-43-induced HSC apoptosis. Furthermore, SC-43 interacted with the N-SH2 domain of SHP-1 to enhance the activity of SHP-1 as its antifibrotic mechanism. In conclusion, the SHP-1-STAT3 pathway is crucial in fibrogenesis. SC-43 significantly ameliorates liver fibrosis through SHP-1 upregulation. A SHP-1-targeted antifibrotic therapy may represent a druggable strategy for antifibrotic drug discovery.


Asunto(s)
Cirrosis Hepática/tratamiento farmacológico , Éteres Fenílicos/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Proteína Tirosina Fosfatasa no Receptora Tipo 6/metabolismo , Animales , Apoptosis/efectos de los fármacos , Conductos Biliares/patología , Tetracloruro de Carbono , Línea Celular , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Células Estrelladas Hepáticas/efectos de los fármacos , Células Estrelladas Hepáticas/metabolismo , Humanos , Ligadura , Cirrosis Hepática/patología , Cirrosis Hepática/prevención & control , Masculino , Ratones Endogámicos C57BL , Mutación/genética , Éteres Fenílicos/química , Éteres Fenílicos/farmacología , Compuestos de Fenilurea/química , Compuestos de Fenilurea/farmacología , Dominios Proteicos , Proteína Tirosina Fosfatasa no Receptora Tipo 6/química , Ratas , Factor de Transcripción STAT3/metabolismo , Sorafenib/química , Sorafenib/farmacología , Sorafenib/uso terapéutico
2.
Biol Pharm Bull ; 33(5): 816-24, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20460760

RESUMEN

Shikonin, a major ingredient in the Chinese traditional herb Lithospermum erythrorhixon, exhibits multiple biological functions including antimicrobial, anti-inflammatory, and antitumor effects. In this study, we delineated the molecular mechanisms of shikonin in the apoptosis of 143B osteosarcoma cells. Shikonin reduced the cell viability of 143B cells in a dose- and time-dependent manner. The IC(50) at 24 h and 48 h for 143B cells was 4.55 and 2.01microM, respectively. A significantly elicited hypodiploid cell population was found in cells treated with 2, 4, and 8microM shikonin for 24 h. Moreover, treatment with shikonin induced reactive oxygen species (ROS) generation, increased extracellular signal-regulated kinase (ERK) phosphorylation, decreased B-cell lymphoma-2 (Bcl2) expression, and was accompanied by poly(ADP-ribose) polymerase (PARP) cleavage. Pretreatment with the antioxidant agent N-acetyl cysteine (NAC) not only reversed shikonin-induced ROS generation but also significantly attenuated the cytotoxic effects of shikonin in 143B cells. Furthermore, NAC attenuated shikonin-induced ERK phosphorylation. Taken together, our results reveal that shikonin increased ROS generation and ERK activation, and reduced Bcl2, which consequently caused the cells to undergo apoptosis. Therefore, shikonin may be a promising chemotherapeutic agent for osteosarcoma treatment.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Apoptosis/efectos de los fármacos , Neoplasias Óseas/tratamiento farmacológico , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Naftoquinonas/farmacología , Osteosarcoma/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Antineoplásicos Fitogénicos/uso terapéutico , Antioxidantes/farmacología , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Humanos , Concentración 50 Inhibidora , Naftoquinonas/uso terapéutico , Osteosarcoma/metabolismo , Fosforilación , Fitoterapia , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
3.
Food Chem Toxicol ; 48(2): 716-21, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19963029

RESUMEN

Ludwigia octovalvis is an aquatic plant widely distributed in Taiwan. It is traditionally used as a diuretic and is consumed as health drink. In this study, we evaluated the anti-proliferative activity of extracts and active constituent (chlorophyll a; CHL-a) of L. octovalvis in 3T3-L1 adipocytes; its mode of action on apoptosis was also investigated. Results showed that, among the different extracts and fractions, the ethylacetate layer (EAL) possessed the most potent anti-proliferative activity. Activity guided fractionation of the EAL obtained the bioactive constituent CHL-a (IC50: 24.10+/-0.83 nM). At concentrations 5-30 nM, CHL-a exhibited a dose-dependent accumulation of the Sub-G1 peak and caused cell cycle arrest at the G0/G1 phase. At 30 nM, it significantly reduced the cell viability, induced the appearance of DNA fragments, and enhanced the activation of caspase-3. Western blot data revealed that CHL-a decreased the level of Bcl-2, and increased the expression of CD95 (APO-1/CD95) and Bax. Furthermore, CHL-a up-regulated the AMPK and p-AMPK levels, and down-regulated the expression of PPAR-gamma. These results conclude that CHL-a possesses potent anti-proliferative activity, and its apoptotic effects on 3T3-L1 adipocytes are mediated through the activation of CD95 (APO-1/CD95) system and the AMPK signaling pathway.


Asunto(s)
Células 3T3-L1/efectos de los fármacos , Fármacos Antiobesidad/farmacología , Clorofila/farmacología , Onagraceae/química , Proteínas Quinasas/efectos de los fármacos , Receptor fas/efectos de los fármacos , Células 3T3-L1/metabolismo , Células 3T3-L1/patología , Quinasas de la Proteína-Quinasa Activada por el AMP , Adipocitos/efectos de los fármacos , Adipocitos/metabolismo , Adipocitos/patología , Animales , Fármacos Antiobesidad/química , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Fraccionamiento Químico , Clorofila/química , Clorofila A , Ratones , PPAR gamma/efectos de los fármacos , PPAR gamma/metabolismo , Extractos Vegetales/química , Proteínas Quinasas/metabolismo , Receptor fas/metabolismo
4.
Environ Monit Assess ; 151(1-4): 251-8, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18415693

RESUMEN

Industrial wastewater typically contains various metal ions. Traditional metal ion treatment processes such as chemical precipitation generate large volumes of toxic sludge which needs to be further solidified or disposed of. The ferrite process (FP), which is another effective approach of treating metal ion-containing wastewater, can crystallize metal ions into ferrites; the sludge easily precipitates, is stable and can be recycling. This investigation explores the feasibility of the Fenton process and the FP (FFP) for treating wastewater that contains metal ions. It considers one factor that adds noise to the FP, ethylenediaminetetraacetic acid, and establishes the optimum parameters of each procedure. The analytical results demonstrate that the proper conditions for Fenton process were pH = 2, [Fe(2+)] = 10(-2) M, H(2)O(2) dosing rate = 5 x 10(-4) mol min(-1), reaction time = 12 min. For the proposed multi-stage FP, the preferred Fe(2+) dosage was 0.098 mol in each stage and the sludge met the toxicity characteristic leaching procedure standards. Following the FFP, the effluent water or the sludge easily met Taiwan's standards. Finally, the SEM test demonstrated that size of the sludge particles was 50-110 nm.


Asunto(s)
Compuestos Férricos/química , Residuos Industriales/análisis , Aguas del Alcantarillado/análisis , Eliminación de Residuos Líquidos/métodos , Quelantes/química , Ácido Edético/química , Humanos , Concentración de Iones de Hidrógeno , Metales/análisis , Oxidación-Reducción , Tamaño de la Partícula , Taiwán , Purificación del Agua/instrumentación , Purificación del Agua/métodos
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