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1.
Front Pharmacol ; 12: 685265, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34630078

RESUMEN

Background: Previous studies have shown that anesthetic techniques can affect outcomes of cancer surgery. We investigated the association between anesthetic techniques and patient outcomes after elective epithelial ovarian cancer surgery. Methods: This was a retrospective cohort study of patients who received elective open surgery for epithelial ovarian cancer between January 2009 and December 2014. Patients were grouped according to the administration of propofol or desflurane anesthesia. Kaplan-Meier analysis was performed, and survival curves were constructed from the date of surgery to death. Univariate and multivariate Cox regression models were used to compare hazard ratios for death after propensity matching. Subgroup analyses were performed for age, body mass index, preoperative carbohydrate antigen-125 level, International Federation of Gynecology and Obstetrics staging, and operation and anesthesia time. Results: In total, 165 patients (76 deaths, 46.1%) who received desflurane anesthesia and 119 (30 deaths, 25.2%) who received propofol anesthesia were eligible for analysis. After propensity matching, 104 patients were included in each group. In the matched analysis, patients who received propofol anesthesia had better survival with a hazard ratio of 0.52 (95% confidence interval, 0.33-0.81; p = 0.005). Subgroup analyses also showed significantly better survival with old age, high body mass index, elevated carbohydrate antigen-125 level, advanced International Federation of Gynecology and Obstetrics stage, and prolonged operation and anesthesia time in the matched propofol group. In addition, patients administered with propofol anesthesia had less postoperative recurrence and metastasis than those administered with desflurane anesthesia in the matched analysis. Conclusion: Propofol anesthesia was associated with better survival in patients who underwent elective epithelial ovarian cancer open surgery. Prospective studies are warranted to evaluate the effects of propofol anesthesia on oncological outcomes in patients with epithelial ovarian cancer.

2.
Theranostics ; 8(22): 6322-6349, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30613300

RESUMEN

Cancer theranostics is one of the most important approaches for detecting and treating patients at an early stage. To develop such a technique, accurate detection, specific targeting, and controlled delivery are the key components. Various kinds of nanoparticles have been proposed and demonstrated as potential nanovehicles for cancer theranostics. Among them, polymer-like dendrimers and copolymer-based core-shell nanoparticles could potentially be the best possible choices. At present, magnetic resonance imaging (MRI) is widely used for clinical purposes and is generally considered the most convenient and noninvasive imaging modality. Superparamagnetic iron oxide (SPIO) and gadolinium (Gd)-based dendrimers are the major nanostructures that are currently being investigated as nanovehicles for cancer theranostics using MRI. These structures are capable of specific targeting of tumors as well as controlled drug or gene delivery to tumor sites using pH, temperature, or alternating magnetic field (AMF)-controlled mechanisms. Recently, Gd-based pseudo-porous polymer-dendrimer supramolecular nanoparticles have shown 4-fold higher T1 relaxivity along with highly efficient AMF-guided drug release properties. Core-shell copolymer-based nanovehicles are an equally attractive alternative for designing contrast agents and for delivering anti-cancer drugs. Various copolymer materials could be used as core and shell components to provide biostability, modifiable surface properties, and even adjustable imaging contrast enhancement. Recent advances and challenges in MRI cancer theranostics using dendrimer- and copolymer-based nanovehicles have been summarized in this review article, along with new unpublished research results from our laboratories.


Asunto(s)
Dendrímeros/química , Imagen por Resonancia Magnética/instrumentación , Nanopartículas/química , Neoplasias/diagnóstico por imagen , Polímeros/química , Nanomedicina Teranóstica/instrumentación , Animales , Sistemas de Liberación de Medicamentos/instrumentación , Sistemas de Liberación de Medicamentos/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Neoplasias/tratamiento farmacológico , Nanomedicina Teranóstica/métodos
3.
Int J Nanomedicine ; 12: 6273-6287, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28894366

RESUMEN

Magnetic resonance (MR) nano-theranostic hyperthermia uses magnetic nanoparticles to target and accumulate at the lesions and generate heat to kill lesion cells directly through hyperthermia or indirectly through thermal activation and control releasing of drugs. Preclinical and translational applications of MR nano-theranostic hyperthermia are currently limited by a few major theoretical difficulties and experimental challenges in in vivo conditions. For example, conventional models for estimating the heat generated and the optimal magnetic nanoparticle sizes for hyperthermia do not accurately reproduce reported in vivo experimental results. In this work, a revised cluster-based model was proposed to predict the specific loss power (SLP) by explicitly considering magnetic nanoparticle aggregation in in vivo conditions. By comparing with the reported experimental results of magnetite Fe3O4 and cobalt ferrite CoFe2O4 magnetic nanoparticles, it is shown that the revised cluster-based model provides a more accurate prediction of the experimental values than the conventional models that assume magnetic nanoparticles act as single units. It also provides a clear physical picture: the aggregation of magnetic nanoparticles increases the cluster magnetic anisotropy while reducing both the cluster domain magnetization and the average magnetic moment, which, in turn, shift the predicted SLP toward a smaller magnetic nanoparticle diameter with lower peak values. As a result, the heating efficiency and the SLP values are decreased. The improvement in the prediction accuracy in in vivo conditions is particularly pronounced when the magnetic nanoparticle diameter is in the range of ~10-20 nm. This happens to be an important size range for MR cancer nano-theranostics, as it exhibits the highest efficacy against both primary and metastatic tumors in vivo. Our studies show that a relatively 20%-25% smaller magnetic nanoparticle diameter should be chosen to reach the maximal heating efficiency in comparison with the optimal size predicted by previous models.


Asunto(s)
Hipertermia Inducida/métodos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapéutico , Modelos Teóricos , Nanomedicina Teranóstica/métodos , Animales , Anisotropía , Cobalto/química , Compuestos Férricos/química , Óxido Ferrosoférrico/química , Humanos , Hipertermia Inducida/instrumentación , Ratones , Neoplasias/terapia , Nanomedicina Teranóstica/instrumentación , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Proc Natl Acad Sci U S A ; 114(16): 4207-4212, 2017 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-28373545

RESUMEN

Global distribution of hepatocellular carcinomas (HCCs) is dominated by its incidence in developing countries, accounting for >700,000 estimated deaths per year, with dietary exposures to aflatoxin (AFB1) and subsequent DNA adduct formation being a significant driver. Genetic variants that increase individual susceptibility to AFB1-induced HCCs are poorly understood. Herein, it is shown that the DNA base excision repair (BER) enzyme, DNA glycosylase NEIL1, efficiently recognizes and excises the highly mutagenic imidazole ring-opened AFB1-deoxyguanosine adduct (AFB1-Fapy-dG). Consistent with this in vitro result, newborn mice injected with AFB1 show significant increases in the levels of AFB1-Fapy-dG in Neil1-/- vs. wild-type liver DNA. Further, Neil1-/- mice are highly susceptible to AFB1-induced HCCs relative to WT controls, with both the frequency and average size of hepatocellular carcinomas being elevated in Neil1-/- The magnitude of this effect in Neil1-/- mice is greater than that previously measured in Xeroderma pigmentosum complementation group A (XPA) mice that are deficient in nucleotide excision repair (NER). Given that several human polymorphic variants of NEIL1 are catalytically inactive for their DNA glycosylase activity, these deficiencies may increase susceptibility to AFB1-associated HCCs.


Asunto(s)
Aflatoxinas/toxicidad , Carcinoma Hepatocelular/prevención & control , Aductos de ADN/efectos de los fármacos , ADN Glicosilasas/fisiología , Neoplasias Hepáticas Experimentales/prevención & control , Sustancias Protectoras/farmacología , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Femenino , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/metabolismo , Neoplasias Hepáticas Experimentales/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Venenos/toxicidad
5.
Int J Mol Sci ; 17(12)2016 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-27941627

RESUMEN

Cuscuta seeds and whole plant have been used to nourish the liver and kidney. This study was aimed to investigate the hepatoprotective activity of the ethanol extract of Cuscuta campestris Yunck. whole plant (CCEtOH). The hepatoprotective effect of CCEtOH (20, 100 and 500 mg/kg) was evaluated on carbon tetrachloride (CCl4)-induced chronic liver injury. Serum alanine aminotransferase, aspartate aminotransferase, triglyceride and cholesterol were measured and the fibrosis was histologically examined. CCEtOH exhibited a significant inhibition of the increase of serum alanine aminotransferase, aspartate aminotransferase, triglyceride and cholesterol. Histological analyses showed that fibrosis of liver induced by CCl4 were significantly reduced by CCEtOH. In addition, 20, 100 and 500 mg/kg of the extract decreased the level of malondialdehyde (MDA) and enhanced the activities of anti-oxidative enzymes including superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRd) in the liver. We demonstrate that the hepatoprotective mechanisms of CCEtOH were likely to be associated to the decrease in MDA level by increasing the activities of antioxidant enzymes such as SOD, GPx and GRd. In addition, our findings provide evidence that C. campestris Yunck. whole plant possesses a hepatoprotective activity to ameliorate chronic liver injury.


Asunto(s)
Antioxidantes/uso terapéutico , Cuscuta/química , Hígado/efectos de los fármacos , Hígado/metabolismo , Extractos Vegetales/farmacología , Alanina Transaminasa/sangre , Animales , Antioxidantes/química , Aspartato Aminotransferasas/sangre , Intoxicación por Tetracloruro de Carbono , Catalasa/metabolismo , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Hígado/lesiones , Masculino , Malondialdehído/metabolismo , Ratones , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Semillas/química , Superóxido Dismutasa/metabolismo
6.
Proc Natl Acad Sci U S A ; 113(48): 13774-13779, 2016 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-27849610

RESUMEN

Routine dietary consumption of foods that contain aflatoxins is the second leading cause of environmental carcinogenesis worldwide. Aflatoxin-driven mutagenesis is initiated through metabolic activation of aflatoxin B1 (AFB1) to its epoxide form that reacts with N7 guanine in DNA. The resulting AFB1-N7-dG adduct undergoes either spontaneous depurination or imidazole-ring opening yielding formamidopyrimidine AFB1 (AFB1-Fapy-dG). Because this latter adduct is known to persist in human tissues and contributes to the high frequency G-to-T mutation signature associated with many hepatocellular carcinomas, we sought to establish the identity of the polymerase(s) involved in processing this lesion. Although our previous biochemical analyses demonstrated the ability of polymerase ζ (pol ζ) to incorporate an A opposite AFB1-Fapy-dG and extend from this mismatch, biological evidence supporting a unique role for this polymerase in cellular tolerance following aflatoxin exposure has not been established. Following challenge with AFB1, survival of mouse cells deficient in pol ζ (Rev3L-/-) was significantly reduced relative to Rev3L+/- cells or Rev3L-/- cells complemented through expression of the wild-type human REV3L. Furthermore, cell-cycle progression of Rev3L-/- mouse embryo fibroblasts was arrested in late S/G2 following AFB1 exposure. These Rev3L-/- cells showed an increase in replication-dependent formation of γ-H2AX foci, micronuclei, and chromosomal aberrations (chromatid breaks and radials) relative to Rev3L+/- cells. These data suggest that pol ζ is essential for processing AFB1-induced DNA adducts and that, in its absence, cells do not have an efficient backup polymerase or a repair/tolerance mechanism facilitating survival.


Asunto(s)
Carcinoma Hepatocelular/genética , Proteínas de Unión al ADN/genética , ADN Polimerasa Dirigida por ADN/genética , Neoplasias Hepáticas/genética , Aflatoxina B1/análogos & derivados , Aflatoxina B1/genética , Aflatoxina B1/toxicidad , Aflatoxinas/toxicidad , Animales , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/patología , Supervivencia Celular/efectos de los fármacos , Aberraciones Cromosómicas/efectos de los fármacos , Citidina/análogos & derivados , Citidina/genética , Citidina/toxicidad , Aductos de ADN/efectos de los fármacos , Aductos de ADN/genética , Daño del ADN/efectos de los fármacos , Reparación del ADN/genética , ADN Polimerasa Dirigida por ADN/química , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/patología , Ratones , Mutagénesis/efectos de los fármacos , Mutagénesis/genética , Mutación
7.
Curr Pharm Des ; 21(36): 5256-66, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26412354

RESUMEN

Glioblastoma multiforme (GBM) is one of the most challenging diseases to treat in clinical oncology due to its high mortality rates and inefficient conventional treatment methods. Difficulties with early detection, post-surgical recurrences, and resistance to chemotherapy and/or radiotherapy are important reasons for the poor prognosis of those with GBM. Over the past few decades, magnetic resonance (MR) theranostics using magnetic nanoparticles has shown unique advantages and great promises for the diagnosis and treatment of cancers. Magnetic nanoparticles not only serve as "molecular beacons" to enhance tumor contrast in magnetic resonance imaging (MRI), but also serve as "molecular bullets" for targeted drug delivery, controlled release, and induced hyperthermia. Moreover, multiple functions of magnetic nanoparticles can be synergistically engineered into a single nanoplatform, making it possible to simultaneously image, treat, target, and monitor the targeted lesions. The multi-functionality of nanoparticles, also called nano-theranostics, gives rises to effective new approaches for combating GBM. In this work, recent research and progress concerning the applications of MR nano-theranostics on GBM using magnetic nanoparticles will be highlighted, focusing on topics such as diagnosis, therapy, targeting, and hyperthermia, as well as outstanding challenges for MR nanotheranostics in treating GBM. The conclusions are generally applicable to other types of brain tumors.


Asunto(s)
Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Nanopartículas de Magnetita , Nanomedicina Teranóstica/métodos , Animales , Antineoplásicos/administración & dosificación , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Sistemas de Liberación de Medicamentos , Glioblastoma/diagnóstico , Glioblastoma/patología , Humanos , Imagen por Resonancia Magnética/métodos
8.
J Biol Chem ; 289(26): 18497-506, 2014 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-24838242

RESUMEN

Hepatocellular carcinomas (HCCs) are the third leading cause of cancer deaths worldwide. The highest rates of early onset HCCs occur in geographical regions with high aflatoxin B1 (AFB1) exposure, concomitant with hepatitis B infection. Although the carcinogenic basis of AFB1 has been ascribed to its mutagenic effects, the mutagenic property of the primary AFB1-DNA adduct, AFB1-N7-Gua, in mammalian cells has not been studied extensively. Taking advantage of the ability to create vectors containing a site-specific DNA adduct, the mutagenic potential was determined in primate cells. This adduct was highly mutagenic following replication in COS-7 cells, with a mutation frequency of 45%. The spectrum of mutations was predominantly G to T base substitutions, a result that is consistent with previous mutation data derived from aflatoxin-associated HCCs. To assess which DNA polymerases (pol) might contribute to the mutational outcome, in vitro replication studies were performed. Unexpectedly, replicative pol δ and the error-prone translesion synthesis pol ζ were able to accurately bypass AFB1-N7-Gua. In contrast, replication bypass using pol κ was shown to occur with low fidelity and could account for the commonly detected G to T transversions.


Asunto(s)
Aflatoxina B1/toxicidad , Carcinoma Hepatocelular/genética , Aductos de ADN/genética , Replicación del ADN , Neoplasias Hepáticas/genética , Aflatoxina B1/genética , Aflatoxina B1/metabolismo , Animales , Células COS , Carcinoma Hepatocelular/inducido químicamente , Chlorocebus aethiops , Aductos de ADN/metabolismo , Daño del ADN , Reparación del ADN , ADN Polimerasa Dirigida por ADN/metabolismo , Humanos , Neoplasias Hepáticas/inducido químicamente , Mutación Puntual
9.
Carcinogenesis ; 35(7): 1461-8, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24398669

RESUMEN

Aflatoxin B1 (AFB1) is a known carcinogen associated with early-onset hepatocellular carcinoma (HCC) and is thought to contribute to over half a million new HCCs per year. Although some of the fundamental risk factors are established, the molecular basis of AFB1-induced mutagenesis in primate cells has not been rigorously investigated. To gain insights into genome instability that is produced as a result of replicating DNAs containing AFB1 adducts, site-specific mutagenesis assays were used to establish the mutagenic potential of the persistent ring-opened AFB1 adduct, AFB1-formamidopyrimidine (AFB1-FAPY). This lesion was highly mutagenic, yielding replication error frequencies of 97%, with the predominant base substitution being a G to T transversion. This transversion is consistent with previous mutational data derived from aflatoxin-associated HCCs. In vitro translesion synthesis assays demonstrated that polymerase (pol) ζ was the most likely candidate polymerase that is responsible for the G to T mutations induced by this adduct.


Asunto(s)
Aflatoxina B1/efectos adversos , Carcinoma Hepatocelular/genética , Aductos de ADN/efectos adversos , Replicación del ADN/genética , Neoplasias Hepáticas/genética , Mutación/genética , Pirimidinas/efectos adversos , Animales , Células COS , Carcinoma Hepatocelular/inducido químicamente , Carcinoma Hepatocelular/patología , Chlorocebus aethiops , ADN de Cadena Simple/genética , Humanos , Neoplasias Hepáticas/inducido químicamente , Neoplasias Hepáticas/patología , Mutagénesis Sitio-Dirigida , Reacción en Cadena de la Polimerasa
10.
Am J Chin Med ; 42(1): 223-42, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24467546

RESUMEN

The seeds of Cuscuta chinensis, Cuscutae Semen, are commonly used as a medicinal material for treating the aching and weakness of the loins and knees, tonifying the defects of the liver and the kidney, and treating the diarrhea due to hypofunction of the kidney and the spleen. Since aching and inflammation are highly correlated with such diseases, the aim of this study is to investigate the possible antinociceptive and anti-inflammatory mechanisms of the seeds of C. chinensis. The antinociceptive effect of the seeds of C. chinensis was evaluated via the acetic acid-induced writhing response and formalin-induced paw licking methods. The anti-inflammatory effect was evaluated via the λ-carrageenan induced mouse paw edema method. The results found that 100 and 500 mg/kg of the methanol extract of the seeds of C. chinensis( CC MeOH ) significantly decreased (p < 0.01 and p < 0.001, respectively) the writhing response in the acetic acid assay. Additionally, 20-500 mg/kg of CC MeOH significantly decreased licking time at the early (20 and 100 mg/kg, p < 0.001) and late phases (100 mg/kg, p < 0.01; 500 mg/kg, p < 0.001) of the formalin test, respectively. Furthermore, CC MeOH (100 and 500 mg/kg) significantly decreased (p < 0.01 and p < 0.001, respectively) edema paw volume four hours after λ-carrageenan had been injected. The results in the following study also revealed that the anti-inflammatory mechanism of CC MeOH may be due to declined levels of NO and MDA in the edema paw by increasing the activities of SOD, GPx and GRd in the liver. In addition, CC MeOH also decreased IL-1ß, IL-6, NF-κB, TNF-α, and COX-2 levels. This is the first study to demonstrate the possible mechanisms for the antinociceptive and anti-inflammatory effects of CC MeOH in vivo. Thus, it provides evidence for the treatment of Cuscutae Semen in inflammatory diseases.


Asunto(s)
Analgésicos , Antiinflamatorios , Cuscuta , Edema/tratamiento farmacológico , Extractos Vegetales/farmacología , Extractos Vegetales/uso terapéutico , Animales , Carragenina , Modelos Animales de Enfermedad , Edema/inducido químicamente , Edema/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Hígado/enzimología , Masculino , Ratones , Ratones Endogámicos ICR , FN-kappa B/metabolismo , Óxido Nítrico/metabolismo , Prostaglandina-Endoperóxido Sintasas/metabolismo , Semillas , Superóxido Dismutasa/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo
11.
Am J Chin Med ; 41(2): 405-23, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23548129

RESUMEN

Actinidia callosa var. ephippioides (ACE) has been widely used to treat anti-pyretic, antinociceptive, anti-inflammation, abdominal pain and fever in Taiwan. This study aims to determine the mechanism of anti-inflammatory activities of ethyl acetate fraction of ACE (EA-ACE) using a model of λ-carrageenan (Carr)-induced paw edema in mouse model. In HPLC analysis, chemical characterization of EA-ACE was established. In order to investigate the anti-inflammatory mechanism of EA-ACE, we have detected the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) and the levels of malondialdehyde (MDA) in the paw edema. Serum NO, tumor necrosis factor α (TNF-α), and interleukin-1ß (IL-1ß) were evaluated. Chemical characterization from HPLC indicated that EA-ACE contains betulinic acid, ursolic acid and oleanolic acid. In the anti-inflammatory test, EA-ACE decreased the paw edema after Carr administration, increased the activities of CAT, SOD, and GPx and decreased the MDA level in the edema paw at the 5th hr after Carr injection. EA-ACE affects the serum NO, TNF-α, and IL-1ß levels at the 5th hr after Carr injection. EA-ACE decreased Carr-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions by Western blotting. Actinidia callosa var. ephippioides have the potential to provide a therapeutic approach to inflammation-associated disorders.


Asunto(s)
Actinidia/química , Antiinflamatorios/administración & dosificación , Citocinas/sangre , Medicamentos Herbarios Chinos/administración & dosificación , Edema/tratamiento farmacológico , Mediadores de Inflamación/sangre , Animales , Antiinflamatorios/química , Regulación hacia Abajo/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Edema/sangre , Edema/inmunología , Humanos , Interleucina-1beta/sangre , Masculino , Malondialdehído/inmunología , Ratones , Ratones Endogámicos ICR , Óxido Nítrico/sangre , Superóxido Dismutasa/inmunología , Factor de Necrosis Tumoral alfa/sangre
12.
Am J Chin Med ; 40(2): 335-48, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22419427

RESUMEN

Inflammation is related to several chronic diseases, including cancer and atherosclerosis. Taxillus sutchuenensis (Lecomte) Danser is a special folk medicinal plant in Taiwan. The aim of this study was to evaluate the antioxidant, anti-inflammatory, and antiproliferative activities of the aqueous-thanol extract from T. sutchuenensis (AETS) and its fractions. TEAC, DPPH radicals, total phenolic compounds, total flavonoid content, inhibition of NO production in LPS-induced RAW264.7 cells, and inhibition of cancer cell proliferation were tested. Among all fractions, the ethyl-acetate (EA) fraction showed the highest TEAC and DPPH radical scavenging activities. The EA fraction also had the highest polyphenol and flavonoid content. The EA fractions also decreased LPS-induced NO production and the expression of iNOS and COX-2 in RAW264.7 cells. The antiproliferative activities of the aqueous/ethanol extract and fractions were studied in vitro using A549 cells, and the results were consistent with their antioxidant capacities. EA fractions had the highest antiproliferative activity with an IC(50) of 454.38 ± 1.48 µg/ml. Quercetin also had antioxidant, anti-inflammatory, and antiproliferative activities. Quercetin might be an important bioactive compound in T. sutchuenensis. The experimental data indicated that T. sutchuenensis is a potent antioxidant medicinal plant, and such efficacy may be mainly attributed to its polyphenolic compounds.


Asunto(s)
Antiinflamatorios/inmunología , Antioxidantes/farmacología , Proliferación Celular/efectos de los fármacos , Inhibidores de Crecimiento/farmacología , Loranthaceae/química , Extractos Vegetales/farmacología , Animales , Línea Celular , Humanos , Ratones , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Quercetina/farmacología
13.
Artículo en Inglés | MEDLINE | ID: mdl-23346188

RESUMEN

The aim of this study was to investigate the possible analgesic and anti-inflammatory mechanisms of the ethanolic extract of A. morrisonensis Hayata (AM(EtOH)). Two models were employed for evaluation of the analgesic effects: acetic acid-induced writhing response and formalin-induced paw licking. The results demonstrated that AM(EtOH) decreased writhing response for both the acetic acid assay and the licking time in the formalin test. The anti-inflammatory effect was evaluated by paw edema of mice induced by λ-carrageenan. AM(EtOH) significantly decreased induced paw edema three to four hours after λ-carrageenan injection. Additionally, the results indicated that the anti-inflammatory mechanism of AM(EtOH) may be due to the declined levels of nitric oxide (NO) and malondialdehyde (MDA) in the edematous paw. Furthermore, AM(EtOH) decreased the tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) levels, leading to the reduction of prostaglandins and subsequently alleviated edema. Isolation and purification of the AM(EtOH) extract determined p-hydroxyacetophenone to be a major component at 130 mg/g of extract. No mortality was observed in the acute toxicity test given at the dose of 10 g/kg. This study demonstrated the possible mechanisms for the analgesic and anti-inflammatory effects of AM(EtOH) for mice and provided evidence for the ethnobotanical uses of A. morrisonensis in treating inflammatory diseases.

14.
DNA Repair (Amst) ; 10(12): 1282-93, 2011 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-22041025

RESUMEN

Inflammation associated reactive oxygen and nitrogen species (RONs), including peroxynitrite (ONOO(-)) and nitric oxide (NO), create base lesions that potentially play a role in the toxicity and large genomic rearrangements associated with many malignancies. Little is known about the role of base excision repair (BER) in removing these endogenous DNA lesions. Here, we explore the role of X-ray repair cross-complementing group 1 (XRCC1) in attenuating RONs-induced genotoxicity. XRCC1 is a scaffold protein critical for BER for which polymorphisms modulate the risk of cancer. We exploited CHO and human glioblastoma cell lines engineered to express varied levels of BER proteins to study XRCC1. Cytotoxicity and the levels of DNA repair intermediates (single-strand breaks; SSB) were evaluated following exposure of the cells to the ONOO(-) donor, SIN-1, and to gaseous NO. XRCC1 null cells were slightly more sensitive to SIN-1 than wild-type cells. We used small-scale bioreactors to expose cells to NO and found that XRCC1-deficient CHO cells were not sensitive. However, using a molecular beacon assay to test lesion removal in vitro, we found that XRCC1 facilitates AAG-initiated excision of two key NO-induced DNA lesions: 1,N(6)-ethenoadenine and hypoxanthine. Furthermore, overexpression of AAG rendered XRCC1-deficient cells sensitive to NO-induced DNA damage. These results show that AAG is a key glycosylase for BER of NO-induced DNA damage and that XRCC1's role in modulating sensitivity to RONs is dependent upon the cellular level of AAG. This demonstrates the importance of considering the expression of other components of the BER pathway when evaluating the impact of XRCC1 polymorphisms on cancer risk.


Asunto(s)
Reparación del ADN/efectos de los fármacos , Proteínas de Unión al ADN/metabolismo , Óxido Nítrico/toxicidad , Animales , Células CHO , Extractos Celulares , Línea Celular Tumoral , Cricetinae , Cricetulus , Inestabilidad Genómica/efectos de los fármacos , Humanos , Metilmetanosulfonato/toxicidad , N-Glicosil Hidrolasas/metabolismo , Ácido Peroxinitroso/toxicidad , Proteína 1 de Reparación por Escisión del Grupo de Complementación Cruzada de las Lesiones por Rayos X
15.
Artículo en Inglés | MEDLINE | ID: mdl-21584194

RESUMEN

Asiatic acid (AA), a pentacyclic triterpene compound in the medicinal plant Centella asiatica, was evaluated for antinociceptive and anti-inflammatory effects. Treatment of male ICR mice with AA significantly inhibited the numbers of acetic acid-induced writhing responses and the formalin-induced pain in the late phase. In the anti-inflammatory test, AA decreased the paw edema at the 4th and 5th h after λ-carrageenan (Carr) administration and increased the activities of catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx) in the liver tissue. AA decreased the nitric oxide (NO), tumor necrosis factor-α (TNF-α), and interleukin-1ß (IL-1ß) levels on serum level at the 5th h after Carr injection. Western blotting revealed that AA decreased Carr-induced inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), and nuclear factor-κB (NF-κB) expressions at the 5th h in the edema paw. An intraperitoneal (i.p.) injection treatment with AA also diminished neutrophil infiltration into sites of inflammation as did indomethacin (Indo). The anti-inflammatory mechanisms of AA might be related to the decrease in the level of MDA, iNOS, COX-2, and NF-κB in the edema paw via increasing the activities of CAT, SOD, and GPx in the liver.

16.
Cancer Res ; 71(6): 2308-17, 2011 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-21406402

RESUMEN

Glioblastoma multiforme (GBM) is a devastating brain tumor with poor prognosis and low median survival time. Standard treatment includes radiation and chemotherapy with the DNA alkylating agent temozolomide (TMZ). However, a large percentage of tumors are resistant to the cytotoxic effects of the TMZ-induced DNA lesion O(6)-methylguanine due to elevated expression of the repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) or a defect in the mismatch repair (MMR) pathway. Although a majority of the TMZ-induced lesions (N7-methylguanine and N3-methyladenine) are base excision repair (BER) substrates, these DNA lesions are also readily repaired. However, blocking BER can enhance response to TMZ and therefore the BER pathway has emerged as an attractive target for reversing TMZ resistance. Our lab has recently reported that inhibition of BER leads to the accumulation of repair intermediates that induce energy depletion-mediated cell death via hyperactivation of poly(ADP-ribose) polymerase. On the basis of our observation that TMZ-induced cell death via BER inhibition is dependent on the availability of nicotinamide adenine dinucleotide (NAD(+)), we have hypothesized that combined BER and NAD(+) biosynthesis inhibition will increase TMZ efficacy in glioblastoma cell lines greater than BER inhibition alone. Importantly, we find that the combination of BER and NAD(+) biosynthesis inhibition significantly sensitizes glioma cells with elevated expression of MGMT and those deficient in MMR, two genotypes normally associated with TMZ resistance. Dual targeting of these two interacting pathways (DNA repair and NAD(+) biosynthesis) may prove to be an effective treatment combination for patients with resistant and recurrent GBM.


Asunto(s)
Reparación del ADN/efectos de los fármacos , Dacarbazina/análogos & derivados , Resistencia a Antineoplásicos/efectos de los fármacos , NAD/biosíntesis , Acrilamidas/farmacología , Adenosina Trifosfato/metabolismo , Antineoplásicos Alquilantes/farmacología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , ADN Glicosilasas/genética , ADN Glicosilasas/metabolismo , Dacarbazina/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/patología , Humanos , Hidroxilaminas/farmacología , Immunoblotting , Metilmetanosulfonato/farmacología , Piperidinas/farmacología , Poli(ADP-Ribosa) Polimerasas/genética , Poli(ADP-Ribosa) Polimerasas/metabolismo , Interferencia de ARN , Temozolomida
17.
Dalton Trans ; 40(14): 3748-53, 2011 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-21380404

RESUMEN

Intermolecular [2+2+2] cycloaddition reaction employing an air-stable ruthenium perchloro-cyclobutenonyl complex as a catalyst is reported. A series of internal alkynes were incorporated with dimethyl acetylene-dicarboxylate in a ratio of 1:2 to give various substituted benzenes in high yield and high chemoselectivity.

18.
Artículo en Inglés | MEDLINE | ID: mdl-19933324

RESUMEN

Pogostemon cablin (PC) is a herbal medicine traditionally applied to treat not only common cold, nausea and diarrhea but also headache and fever. The aim of this study was to investigate the analgesic and anti-inflammatory properties of standardized PC methanol extract (PCMeOH) in vivo. Investigations were performed in mice with two analgesic models. One was acetic acid-induced writhing response and the other formalin-induced paw licking. The anti-inflammatory effect was tested by λ-carrageenan (Carr)-induced mice paw edema. These analgesic experimental results indicated that PCMeOH (1.0 g/kg) decreased the acetic acid-induced writhing responses and PCMeOH (0.5 and 1.0 g/kg) decreased the licking time in the second phase of the formalin test. Moreover, Carr-induced paw edema inflammation was significantly reduced in a dose-dependent manner when PCMeOH (0.5 and 1.0 g/kg) was administered 3 and 4 h after the Carr injection. Mechanistic studies showed that PCMeOH decreased the levels of malondialdehyde in the edema paw by increasing the activities of anti-oxidant enzymes, such as superoxide dismutase, glutathione peroxidase and glutathione reductase, in the liver and decreasing the cyclooxygenase 2 and tumor necrosis factor-α activities in the edema paw. This study has demonstrated the analgesic and anti-inflammatory effects of PCMeOH, thus verifying its popular use in traditional medicine.

19.
Am J Chin Med ; 38(2): 279-91, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20387225

RESUMEN

The present study investigated the effects of luteolin on Abeta (1-40)-induced impairment of Morris water maze (MWM) spatial performance, reference memory, and passive avoidance (PA) behavior in rats. Luteolin treatment was started 4 days before the initiation of behavioral testing (passive avoidance on treatment day of 4-5; MWM spatial performance memory testing on treatment day of 5-7 and MWM reference memory testing on treatment day of 7) and continued until the end of the study. We also measured the activity of Mn-SOD, copper/zinc (Cu/Zn)-SOD and glutathione (GSH) levels in rat cortex and hippocampus to understand the ameliorating effect of luteolin on Abeta (1-40) induced memory impairment. The present results showed that luteolin (5, 10 mg/kg) has a protective effect on Abeta (1-40)-induced memory dysfunction in spatial performance, reference memory, and inhibitory avoidance response impairment. Finally, luteolin also increases the level of Mn-SOD, (Cu/Zn)-SOD and glutathione (GSH) in the cortex and hippocampus to reduce the oxidative stress by Abeta (1-40). Taken together, the results in this study suggest that luteolin (5, 10 mg/kg) treatment improves the learning and memory in Abeta (1-40)-induced cognition deficit in rats. The ameliorating mechanisms of luteolin on Abeta (1-40)-induced amnesia may be related to activating the anti-oxidation system.


Asunto(s)
Péptidos beta-Amiloides/farmacología , Reacción de Prevención/efectos de los fármacos , Luteolina/farmacología , Aprendizaje por Laberinto/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Animales , Relación Dosis-Respuesta a Droga , Glutatión/metabolismo , Masculino , Memoria/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo
20.
Biochem Biophys Res Commun ; 391(1): 1043-8, 2010 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-19995552

RESUMEN

By regulating the amount of protein receptors on the cell membrane and the metabolisms of receptor-bound ligands, endocytosis represents one of the fundamental biological activities that regulate how cells respond to the environment. We report here that a Fab1-YotB-Vac1p-EEA1 (FYVE) domain-containing lipid associated protein, called Phafin2, is preferentially expressed in the human hepatocellular carcinoma (HCC) and is involved in the biogenesis of endosomes. Over-expression of Phafin2 or its FYVE domain results in the formation of enlarged endosomes that are still functional for endocytosis; the biogenesis of such abnormal organelles is mediated by phosphoinositide 3-kinases (PI3K) and Rab5 signaling. Using fluorescence resonance energy transfer measured by fluorescence lifetime imaging microscopy (FLIM-FRET), we further demonstrate in live cells that Phafin2 can directly activate Rab5. By modulating the receptor internalization/recycling and Rab5 activation, Phafin2 affects the density of membranous insulin receptors, and regulates the transcriptional activity of AP-1 that is downstream of the insulin signaling pathway. These results provide a vivid example that an endosome modulator, such as Phafin2, may control the cells' responses to the extracellular cues.


Asunto(s)
Endosomas/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Unión al GTP rab5/metabolismo , Línea Celular Tumoral , Endosomas/ultraestructura , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Receptor de Insulina/metabolismo , Transducción de Señal , Factor de Transcripción AP-1/metabolismo , Proteínas de Transporte Vesicular/genética , Proteínas de Unión al GTP rab5/genética
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