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1.
Am J Chin Med ; 48(8): 1915-1940, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33308096

RESUMEN

Autophagy is an important tightly controlled cellular process that regulates cellular homeostasis and is involved in deciding cell fate such as cell survival and death. The role of autophagy in many intracellular signaling pathways explains its interaction with other different types of cell death, including apoptosis and immunogenic cell death (ICD). The reports showed the complex and intriguing relationship existing between autophagy and immune system signaling pathways. However, the role of autophagy in ICD remains to be clearly elucidated. In this study, we demonstrated that Brucine, a clinically-used small molecule in traditional Chinese medicine, elicited autophagy inhibition. Brucine also triggered cell stress and induced features of ICD, including calreticulin (CRT) exposure and high-mobility group box 1 (HMGB1) release in MDA-MB-231 and CT26 cancer cells. Brucine impaired autolysosomal degradation and exerted a feedback regulation of ERK1/2-mTOR-p70S6K signaling cascade. Brucine-elicited ICD was confirmed by the rejection of CT26 tumor cells, implanted in the mice after vaccination with Brucine-treated CT26 cells. The impaired autophagy contributed to Brucine-induced ICD, as knock-down of Atg5 significantly reduced Brucine-elicited CRT exposure and HMGB1 release. Our results revealed Brucine as a novel autophagy regulator, ICD inducer and hitherto undocumented role of autophagy in ICD. Thus, these results imply the importance of Brucine in cancer immunotherapy. Therefore, Brucine may be used as an ICD inducer and improve its application in cancer treatment with minimized toxicity.


Asunto(s)
Autofagia/efectos de los fármacos , Muerte Celular/genética , Muerte Celular/inmunología , Medicamentos Herbarios Chinos , Lisosomas/efectos de los fármacos , Estricnina/análogos & derivados , Animales , Autofagia/fisiología , Proteína 5 Relacionada con la Autofagia/genética , Calreticulina , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Proteína HMGB1/metabolismo , Humanos , Inmunoterapia , Lisosomas/fisiología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Neoplasias/tratamiento farmacológico , Fitoterapia , Estricnina/farmacología , Estricnina/uso terapéutico
2.
Nat Commun ; 9(1): 4236, 2018 10 12.
Artículo en Inglés | MEDLINE | ID: mdl-30315154

RESUMEN

Chemo-PTT, which combines chemotherapy with photothermal therapy, offers a viable approach for the complete tumor eradication but would likely fail in drug-resistant situations if conventional chemotherapeutic agents are used. Here we show that a type of copper (Cu)-palladium (Pd) alloy tetrapod nanoparticles (TNP-1) presents an ideal solution to the chemo-PTT challenges. TNP-1 exhibit superior near-infrared photothermal conversion efficiency, thanks to their special sharp-tip structure, and induce pro-survival autophagy in a shape- and composition-dependent manner. Inhibition of autophagy with 3-methyl adenine or chloroquine has a remarkable synergistic effect on TNP-1-mediated PTT in triple-negative (4T1), drug-resistant (MCF7/MDR) and patient-derived breast cancer models, achieving a level of efficacy unattainable with TNP-2, the identically-shaped CuPd nanoparticles that have a higher photothermal conversion efficiency but no autophagy-inducing activity. Our results provide a proof-of-concept for a chemo-PTT strategy, which utilizes autophagy inhibitors instead of traditional chemotherapeutic agents and is particularly useful for eradicating drug-resistant cancer.


Asunto(s)
Aleaciones/química , Aleaciones/farmacología , Autofagia/efectos de los fármacos , Cobre/química , Nanopartículas/química , Nanopartículas/uso terapéutico , Paladio/química , Fototerapia/métodos , Aleaciones/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Western Blotting , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Supervivencia Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Femenino , Células HeLa , Humanos , Etiquetado Corte-Fin in Situ , Células MCF-7 , Ratones , Ratones Endogámicos BALB C , Ratones SCID , Especies Reactivas de Oxígeno/metabolismo
3.
Small ; 13(7)2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27925395

RESUMEN

The diverse biological effects of nanomaterials form the basis for their applications in biomedicine but also cause safety issues. Induction of autophagy is a cellular response after nanoparticles exposure. It may be beneficial in some circumstances, yet autophagy-mediated toxicity raises an alarming concern. Previously, it has been reported that upconversion nanoparticles (UCNs) elicit liver damage, with autophagy contributing most of this toxicity. However, the detailed mechanism is unclear. This study reveals persistent presence of enlarged autolysosomes in hepatocytes after exposure to UCNs and SiO2 nanoparticles both in vitro and in vivo. This phenomenon is due to anomaly in the autophagy termination process named autophagic lysosome reformation (ALR). Phosphatidylinositol 4-phosphate (PI(4)P) relocates onto autolysosome membrane, which is a key event of ALR. PI(4)P is then converted into phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2 ) by phosphatidylinositol-4-phosphate 5-kinase. Clathrin is subsequently recruited by PI(4,5)P2 and leads to tubule budding of ALR. Yet it is observed that PI(4)P cannot be converted in nanoparticle-treated hepatocytes cells. Exogenous supplement of PI(4,5)P2 suppresses the enlarged autolysosomes in vitro. Abolishment of these enlarged autolysosomes by autophagy inhibitor relieves the hepatotoxicity of UCNs in vivo. The results provide evidence for disrupted ALR in nanoparticle-treated hepatocytes, suggesting that the termination of nanoparticle-induced autophagy is of equal importance as the initiation.


Asunto(s)
Autofagia , Hepatocitos/citología , Hepatocitos/metabolismo , Lisosomas/metabolismo , Nanopartículas/química , Animales , Autofagia/efectos de los fármacos , Células Cultivadas , Hepatocitos/efectos de los fármacos , Hígado/metabolismo , Lisosomas/efectos de los fármacos , Masculino , Ratones Endogámicos C57BL , Modelos Biológicos , Nanopartículas/toxicidad , Fosfatos de Fosfatidilinositol/metabolismo
4.
Trials ; 17(1): 512, 2016 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-27769284

RESUMEN

BACKGROUND: Although Traditional Chinese Medicine (TCM) has been widely used in clinical settings, a major challenge that remains in TCM is to evaluate its efficacy scientifically. This randomized controlled trial aims to evaluate the efficacy and safety of berberine in the treatment of patients with polycystic ovary syndrome. In order to improve the transparency and research quality of this clinical trial, we prepared this statistical analysis plan (SAP). METHODS: The trial design, primary and secondary outcomes, and safety outcomes were declared to reduce selection biases in data analysis and result reporting. We specified detailed methods for data management and statistical analyses. Statistics in corresponding tables, listings, and graphs were outlined. DISCUSSION: The SAP provided more detailed information than trial protocol on data management and statistical analysis methods. Any post hoc analyses could be identified via referring to this SAP, and the possible selection bias and performance bias will be reduced in the trial. TRIAL REGISTRATION: This study is registered at ClinicalTrials.gov, NCT01138930 , registered on 7 June 2010.


Asunto(s)
Berberina/uso terapéutico , Interpretación Estadística de Datos , Medicamentos Herbarios Chinos/uso terapéutico , Resistencia a la Insulina , Síndrome del Ovario Poliquístico/tratamiento farmacológico , Adolescente , Adulto , Berberina/efectos adversos , Protocolos Clínicos , Medicamentos Herbarios Chinos/efectos adversos , Femenino , Humanos , Modelos Estadísticos , Síndrome del Ovario Poliquístico/diagnóstico , Proyectos de Investigación , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
5.
BMC Complement Altern Med ; 16: 201, 2016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27402016

RESUMEN

BACKGROUND: Qili Qiangxin capsule is a standardized Chinese herbal treatment that is commonly used in China for heart failure (HF) alongside conventional medical care. In 2014, Chinese guidelines for the treatment of chronic HF highlighted Qili Qiangxin capsules as a potentially effective medicine. However, there is at present no high quality review to evaluate the effects and safety of Qili Qiangxin for patients with HF. METHODS: We conducted a systematic review and meta-analysis and followed methods described in our registered protocol [PROSPERO registration: CRD42013006106]. We searched 6 electronic databases to identify randomized clinical trials (RCTs) irrespective of blinding or placebo control of Qili Qiangxin used as an adjuvant treatment for HF. RESULTS: We included a total of 129 RCTs published between 2005 and 2015, involving 11,547 patients, aged 18 to 98 years. Meta-analysis showed no significant difference between Qili Qiangxin plus conventional treatment and conventional treatment alone for mortality (RR 0.53, 95 % CI 0.27 to 1.07). However, compared with conventional treatment alone, Qili Qiangxin plus conventional treatment demonstrated a significant reduction in major cardiovascular events (RR 0.46, 95 % CI 0.34 to 0.64) and a significant reduction in re-hospitalization rate due to HF (RR 0.49, 95 % CI 0.38 to 0.64). Qili Qiangxin also showed significant improvement in cardiac function measured by the New York Heart Association scale (RR 1.38, 95 % CI 1.29 to 1.48) and quality of life as measured by Minnesota Living with Heart Failure Questionnaire (MD -8.48 scores, 95 % CI -9.56 to -7.39). There were no reports of serious adverse events relating to Qili Qiangxin administration. The majority of included trials were of poor methodological quality. CONCLUSIONS: When compared with conventional treatment alone, Qili Qiangxin combined with conventional treatment demonstrated a significant effect in reducing cardiovascular events and re-hospitalization rate, though not in mortality. It appeared to significantly improve quality of life in patients with HF and data from RCTs suggested that Qili Qiangxin is likely safe. This data was drawn from low quality trials and the results of this review must therefore be interpreted with caution. Further research is warranted, ideally involving large, prospective, rigorous trials, in order to confirm these findings.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Insuficiencia Cardíaca/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Humanos , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Adulto Joven
6.
Nanoscale ; 8(25): 12826-33, 2016 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-27297334

RESUMEN

T1-T2 dual modal magnetic resonance imaging (MRI) has attracted considerable interest because it offers complementary diagnostic information, leading to more precise diagnosis. To date, a number of nanostructures have been reported as T1-T2 dual modal MR contrast agents (CAs). However, hybrids of nanocubes with both iron and gadolinium (Gd) elements as T1-T2 dual modal CAs have not been reported. Herein, we report the synthesis of novel core/shell Fe3O4/Gd2O3 nanocubes as T1-T2 dual-modal CAs and their application for enhanced T1-T2 MR imaging of rat livers. A relaxivity study at 1.5 T indicated that our Fe3O4/Gd2O3 nanocubes have an r1 value of 45.24 mM(-1) s(-1) and an r2 value of 186.51 mM(-1) s(-1), which were about two folds of those of Gd2O3 nanoparticles and Fe3O4 nanocubes, respectively. In vivo MR imaging of rats showed both T1-positive and T2-negative contrast enhancements in the livers. We envision that our Fe3O4/Gd2O3 nanocubes could be applied as T1-T2 dual modal MR CAs for a wide range of theranostic applications in the near future.

7.
Int J Syst Evol Microbiol ; 62(Pt 1): 173-178, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21378136

RESUMEN

A Gram-negative, aerobic, short rod-shaped and non-motile bacterium, strain A-1(T), was isolated from a saline soil contaminated with crude oil in Xianhe, Shangdong Province, China. Strain A-1(T) formed yellow colonies, was moderately halophilic and grew with 0.05-27.5% (w/v) total salts (optimum 5-8%), at 10-42 °C (optimum 30 °C) and at pH 5.5-9.0 (optimum pH 7.2). The dominant fatty acids (>5%) were C(16:0), summed feature 3 (comprising C(16:1)ω7c and/or iso-C(15:0) 2-OH), C(18:1)ω7c, C(19:0) cyclo ω8c and C(12:0) 3-OH and the predominant ubiquinone was Q-9. The genomic DNA G+C content was 67.1 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain A-1(T) belonged to the genus Halomonas in the class Gammaproteobacteria. The closest relatives were Halomonas lutea YIM 91125(T) (97.7% 16S rRNA gene sequence similarity), H. muralis LMG 20969(T) (95.6%), H. pantelleriensis AAP(T) (95.5%) and H. kribbensis BH843(T) (95.2%). DNA-DNA relatedness between strain A-1(T) and H. lutea CCTCC AB 206093(T) was 27±3%. On the basis of phenotypic, chemotaxonomic and phylogenetic features, strain A-1(T) should be placed in the genus Halomonas as a representative of a novel species. The name Halomonas xianhensis sp. nov. is proposed, with strain A-1(T) (=CGMCC 1.6848(T) =JCM 14849(T)) as the type strain.


Asunto(s)
Halomonas/clasificación , Halomonas/aislamiento & purificación , Microbiología del Suelo , Técnicas de Tipificación Bacteriana , Composición de Base , China , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Halomonas/genética , Halomonas/fisiología , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Petróleo , Filogenia , Quinonas/análisis , ARN Ribosómico 16S/genética , Sales (Química)/metabolismo , Análisis de Secuencia de ADN , Contaminantes del Suelo , Temperatura
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