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2.
Food Funct ; 13(6): 3621-3631, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35262138

RESUMO

Mast cells (MCs) are the main effector cells in the onset of high-affinity receptor for IgE (FcεRI)-mediated allergic diseases. The aim of this study was to test whether dihydrocoumarin (DHC), a food flavoring agent derived from Melilotus officinalis, can block IgE-induced MC activation effects and to examine the potential molecular mechanisms by which DHC affects MC activation. Rat basophilic leukemia cells (RBLs) and mouse bone marrow-derived mast cells (BMMCs) were sensitized with anti-dinitrophenol (DNP) immunoglobulin (Ig)E antibodies, stimulated with DNP-human serum albumin antigen, and treated with DHC. Western blot analyses were performed to detect the expression of signaling proteins. Murine IgE-mediated passive cutaneous anaphylaxis (PCA) and ovalbumin (OVA)-induced active systemic anaphylaxis (ASA) models were used to examine DHC effects on allergic reactions in vivo. DHC inhibited MC degranulation, as evidenced by reduced ß-hexosaminidase activity and histamine levels, and reduced morphological changes associated with MC activation, namely cellular elongation and F-actin reorganization. DHC inhibited the activation of MAPK, NF-κB, and AP-1 pathways in IgE-activated MCs. Additionally, DHC could attenuate IgE/Ag-induced allergic reactions (dye extravasation and ear thickening) in PCA as well as OVA challenge-induced reactions in ASA mice (body temperature, serum histamine and IL-4 secretion changes). In conclusion, DHC suppressed MC activation. DHC may represent a new MC-suppressing treatment strategy for the treatment of IgE-mediated allergic diseases.


Assuntos
Anafilaxia , Mastócitos , Anafilaxia/tratamento farmacológico , Animais , Degranulação Celular , Aromatizantes/metabolismo , Imunoglobulina E/metabolismo , Inflamação/metabolismo , Camundongos , Anafilaxia Cutânea Passiva , Ratos
3.
J Transl Med ; 19(1): 261, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130714

RESUMO

BACKGROUND: Activator protein-1 (AP1), a c-Fos-JUN transcription factor complex, mediates many cytobiological processes. c-Fos has been implicated in immunoglobulin (Ig)E activation of mast cells (MCs) via high-affinity IgE Fc receptor (FcεRI) binding. This study examined c-Fos involvement in MC activation and tested the effects of the c-Fos/AP1 inhibitor T-5224 on MCs activation and allergic responses. METHODS: In vitro studies were conducted with two MC model systems: rat basophilic leukemia cells (RBLs) and mouse bone marrow derived mast cells (BMMCs). MC degranulation and effector functions were examined with ß-hexosaminidase release and cytokine secretion assays. c-Fos/AP1 was inhibited with T-5224. c-Fos activity was suppressed with short hairpin RNA targeting c-Fos (shFos). In vivo immune responses were evaluated in passive cutaneous anaphylaxis (PCA) and ovalbumin-induced active systemic anaphylaxis (ASA) models, as well as in an oxazolone (OXA)-induced model of atopic dermatitis, a common allergic disease. RESULTS: c-Fos expression was elevated transcriptionally and translationally in IgE-stimulated MCs. c-Fos binding of the Egr1 (early growth response 1) promoter upregulated Egr1 transcription, leading to production of interleukin (IL)4. T-5224 reduced FcεRI-mediated MC degranulation (evidenced by ß-hexosaminidase activity and histamine levels) and diminished EGR1 and IL4 expression. T-5224 attenuated IgE-mediated allergic responses in PCA and ASA models, and it suppressed MC-mediated atopic dermatitis in mice. CONCLUSION: IgE binding can activate MCs via a c-Fos/Egr1/IL-4 axis. T-5224 suppresses MC activation in vitro and in vivo and thus represents a promising potential strategy for targeting MC activation to treat allergic diseases.


Assuntos
Anafilaxia , Mastócitos , Animais , Degranulação Celular , Proteína 1 de Resposta de Crescimento Precoce , Imunoglobulina E , Inflamação , Interleucina-4 , Camundongos , Ratos , Fator de Transcrição AP-1
4.
Pharmacol Res ; 152: 104618, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31891789

RESUMO

Several decades have passed since resveratrol (RSV) was first identified in red wine. Researchers have reported the pleiotropic anti-oxidant, anti-inflammatory, anti-cancer, anti-aging, and neuronal protective effects of resveratrol and its glycosylated derivative. However, few studies have distinguished the minute differences in the properties between resveratrol and its glycosylated derivative in terms of synaptic plasticity. As an abundant natural product of glycosylated resveratrol, the derivative 2,3,4',5-tetrahydroxystilbene-2-O-ß-d-glucoside (TSG) has been determined to be a better option for long-term potentiation (LTP) in the hippocampus under physiological and pathological conditions than resveratrol. TSG, as well as its parent molecule RSV, could elicit early-LTP and recover fast excitatory postsynaptic potentials (EPSPs) in the hippocampus. Using various modalities, including pre- and post-whole-cell patch clamping techniques in the calyx of Held, pharmacological inhibition of the N-methyl-d-aspartic acid receptor (NMDAr) and the α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor (AMPAr) as well as protein kinase C (PKC) activation, we demonstrated that TSG, unlike RSV, could merely promote NMDA-mediated EPSC via PKCß cascade. Our results provide new knowledge that glycosylation of resveratrol could significantly improve its specificity in promoting sole NMDAr mediation of EPSPs, in addition to improving solubility and resistance against oxidation in vivo. These observations could contribute to further exploration of pharmaceutical evaluation of glycosylated stilbene in the future.


Assuntos
Glucosídeos/farmacologia , Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Estilbenos/farmacologia , Animais , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Hipocampo/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteína Quinase C beta/fisiologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/fisiologia
5.
Chin J Integr Med ; 25(6): 431-438, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28497394

RESUMO

OBJECTIVES: To evaluate the characteristics of Bletilla striata microspheres (BSMs) and its effects as an embolic agent in a rabbit model. METHODS: BSMs were prepared with an emulsification-cool condensation-chemical cross-linking method. The characteristics of BSMs in vitro were observed. Embolization experiments were performed in renal artery of rabbit and in a rabbit liver VX2 carcinoma model. Seventy-two New Zealand rabbits were divided into 2 groups, and the right renal artery was embolized with BSMs (200 µm in diameter) in the experimental group and with polyvinyl alcohol (PVA) of the same size in the control group. The pathological findings were examined with hematoxylin-eosin and Masson stainings. Liver and renal functions were tested before and after embolization. VX2 tumor was transplanted in 15 New Zealand rabbits, which were randomly divided into 3 groups (n=5). Group A were treated with saline, group B with a mixture of doxorubicin and lipiodol, and group C with hepatic arterial infusion of BSMs (200 µm in diameter). Tumor growth rate was evaluated by magnetic resonance imaging scan. Apoptosis-related factors (bax, bcl-2) and tumor vascular endothelial cell growth factor (VEGF) were evaluated through immunohistochemical staining. RESULTS: The characteristics of BSMs in vitro were in full compliance with the requirements for use in interventional procedures. In the renal artery embolization experiment, after BSMs intervention, it was more difficult to form collateral circulation than that with PVAs, and the kidney manifested atrophy and calcification. There were no significant difference of liver and renal functions in rabbits between groups. In the liver VX2 carcinoma embolization experiment, compared with group A, the growth rate of VX2 liver tumor and Bcl-2 levels was reduced, while apoptosis index, Bax, and VEGF were increased in group B (P<0.05). There were no significant difference between groups B and C (P>0.05). CONCLUSIONS: The characteristics of BSMs in vitro and in vivo meet the requirements for its use as an embolic agent in interventional approaches.


Assuntos
Embolização Terapêutica , Neoplasias Hepáticas/terapia , Microesferas , Transplante de Neoplasias , Orchidaceae/química , Artéria Renal/patologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Coelhos
6.
Oncotarget ; 8(1): 610-623, 2017 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-27888812

RESUMO

The antitumor effect of Lentinan is thought rely on the activation of immune responses; however, little is known about whether Lentinan also directly attacks cancer cells. We therefore investigated the direct antitumor activity of SLNT (a water-extracted polysaccharide from Lentinus edodes) and its probable mechanism. We showed that SLNT significantly inhibited proliferation of HT-29 colon cancer cells and suppressed tumor growth in nude mice. Annxein V-FITC/PI, DAPI, AO/EB and H&E staining assays all showed that SLNT induced cell apoptosis both in vitro and in vivo. SLNT induced apoptosis by activating Caspase-3 via both intrinsic and extrinsic pathways, which presented as the activation of Caspases-9 and -8, upregulation of cytochrome c and the Bax/Bcl-2 ratio, downregulation of NF-κB, and overproduction of ROS and TNF-α in vitro and in vivo. Pretreatment with the caspase-3 inhibitor Ac-DEVD-CHO or antioxidant NAC blocked SLNT-induced apoptosis. These findings suggest that SLNT exerts direct antitumor effects by inducing cell apoptosis via ROS-mediated intrinsic and TNF-α-mediated extrinsic pathways. SLNT may thus represent a useful candidate for colon cancer prevention and treatment.


Assuntos
Antineoplásicos/farmacologia , Polissacarídeos Fúngicos/farmacologia , Cogumelos Shiitake/química , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Biológicos , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Nat Commun ; 7: 11406, 2016 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-27147225

RESUMO

Immune checkpoint blockade of the inhibitory immune receptors PD-L1, PD-1 and CTLA-4 has emerged as a successful treatment strategy for several advanced cancers. Here we demonstrate that miR-424(322) regulates the PD-L1/PD-1 and CD80/CTLA-4 pathways in chemoresistant ovarian cancer. miR-424(322) is inversely correlated with PD-L1, PD-1, CD80 and CTLA-4 expression. High levels of miR-424(322) in the tumours are positively correlated with the progression-free survival of ovarian cancer patients. Mechanistic investigations demonstrated that miR-424(322) inhibited PD-L1 and CD80 expression through direct binding to the 3'-untranslated region. Restoration of miR-424(322) expression reverses chemoresistance, which is accompanied by blockage of the PD-L1 immune checkpoint. The synergistic effect of chemotherapy and immunotherapy is associated with the proliferation of functional cytotoxic CD8+ T cells and the inhibition of myeloid-derived suppressive cells and regulatory T cells. Collectively, our data suggest a biological and functional interaction between PD-L1 and chemoresistance through the microRNA regulatory cascade.


Assuntos
Antígeno B7-H1/imunologia , Resistencia a Medicamentos Antineoplásicos , MicroRNAs/imunologia , Neoplasias Ovarianas/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Antígeno B7-1/genética , Antígeno B7-1/imunologia , Antígeno B7-H1/genética , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Proliferação de Células , Feminino , Humanos , Camundongos , MicroRNAs/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/fisiopatologia , Linfócitos T Citotóxicos/citologia
8.
J Thorac Dis ; 7(10): 1725-31, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26623094

RESUMO

BACKGROUND: To investigate the effect of long-term smoking on the activity and mRNA expression of cytochrome P450 (CYP) enzymes. METHODS: Sprague-Dawley rats were exposed to passive smoking 6 cigarettes per day for 180 days. A cocktail solution which contained phenacetin (20 mg/kg), tolbutamide (5 mg/kg), chlorzoxazone (20 mg/kg) and midazolam (10 mg/kg) was given orally to rats. Blood samples were collected at pre-specified time points and the concentrations of probe drugs in plasma were determined by HPLC-MS/MS. The corresponding pharmacokinetic parameters were calculated by DAS 3.0. In addition, real-time RT-PCR was used to analyze the mRNA expression of CYP1A2, CYP2C11, CYP2E1 and CYP3A1 in rat liver. RESULTS: There were no significant influences of pharmacokinetic profiles of chlorzoxazone in long-term smoking pretreated rats. But many pharmacokinetic profiles of phenacetin, tolbutamide, and midazolam in long-term smoking pretreated rats were affected significantly (P<0.05). The results suggested that long-term smoking had significant inhibition effects on CYP2C11 and CYP3A1 while CYP1A2 enzyme activity was induced. Furthermore, Long-term smoking had no effects on rat CYP2E1. The mRNA expression results were consistent with the pharmacokinetic results. CONCLUSIONS: Alterations of CYP450 enzyme activities may fasten or slow down excretion with corresponding influence on drug efficacy or toxicity in smokers compared to nonsmokers, which may lead to clinical failures of lung cancer therapy or toxicity in smokers.

9.
Oncol Lett ; 10(1): 291-296, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26171017

RESUMO

Long non-coding RNAs (lncRNAs) have previously been reported to be involved in cancer invasion, proliferation and apoptosis. However, the association between the lncRNA, H19, and esophageal cancer (EC) has remained elusive. In the present study, reverse transcription quantitative-polymerase chain reaction revealed that the expression of H19 was significantly increased and associated with tumor depth and metastasis in 133 EC samples. Furthermore, MTT and Transwell assays revealed that overexpression of H19 in vitro promoted the proliferation and invasion of EC cell lines, whereas knockdown of H19 inhibited the proliferation and invasion of EC cell lines. In addition, it was identified that an upregulation of H19 induced epithelial-to-mesenchymal transition, while the opposite effect was observed following the downregulation of H19. In conclusion, H19 has a significant role in the development of EC and may serve as a potential prognostic marker and therapeutic target for EC.

10.
Oncotarget ; 5(21): 10293-306, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25296973

RESUMO

Castration resistance is a major obstacle to hormonal therapy for prostate cancer patients. Although androgen independence of prostate cancer growth is a known contributing factor to endocrine resistance, the mechanism of androgen receptor deregulation in endocrine resistance is still poorly understood. Herein, the CAMK2N1 was shown to contribute to the human prostate cancer cell growth and survival through AR-dependent signaling. Reduced expression of CAMK2N1 was correlated to recurrence-free survival of prostate cancer patients with high levels of AR expression in their tumor. CAMK2N1 and AR signaling form an auto-regulatory negative feedback loop: CAMK2N1 expression was down-regulated by AR activation; while CAMK2N1 inhibited AR expression and transactivation through CAMKII and AKT pathways. Knockdown of CAMK2N1 in prostate cancer cells alleviated Casodex inhibition of cell growth, while re-expression of CAMK2N1 in castration-resistant cells sensitized the cells to Casodex treatment. Taken together, our findings suggest that CAMK2N1 plays a tumor suppressive role and serves as a crucial determinant of the resistance of prostate cancer to endocrine therapies.


Assuntos
Carcinoma/metabolismo , Neoplasias da Próstata/metabolismo , Proteínas/metabolismo , Receptores Androgênicos/metabolismo , Antagonistas de Androgênios/farmacologia , Anilidas/farmacologia , Antineoplásicos/farmacologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Carcinogênese/genética , Carcinoma/genética , Carcinoma/mortalidade , Processos de Crescimento Celular/genética , Resistência a Medicamentos/genética , Retroalimentação Fisiológica , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Masculino , Nitrilas/farmacologia , Proteína Oncogênica v-akt/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/mortalidade , Proteínas/genética , RNA Interferente Pequeno/genética , Transdução de Sinais/genética , Análise de Sobrevida , Compostos de Tosil/farmacologia , Células Tumorais Cultivadas
11.
Oncotarget ; 5(11): 3611-21, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25003983

RESUMO

Prostate cancer at advanced stages including metastatic and castration-resistant cancer remains incurable due to the lack of effective therapies. The CAMK2N1 gene, cloned and characterized as an inhibitor of CaMKII (calcium/calmodulin-dependent protein kinase II), has been shown to affect tumorigenesis and tumor growth. However, it is still unknown whether CAMK2N1 plays a role in prostate cancer development. We first examined the protein and mRNA levels of CAMK2N1 and observed a significant decrease in human prostate cancers comparing to normal prostate tissues. Re-expression of CAMK2N1 in prostate cancer cells reduced cellular proliferation, arrested cells in G0/G1 phases, and induced apoptotic cell death accompanied by down-regulation of IGF-1, ErbB2, and VEGF downstream kinases PI3K/AKT, as well as the MEK/ERK-mediated signaling pathways. Conversely, knockdown of CAMK2N1 had a significant opposite effects on these phenotypes. Our analyses suggest that CAMK2N1 plays a tumor suppressive role in prostate cancer cells. Reduced CAMK2N1 expression correlates to human prostate cancer progression and predicts poor clinical outcome, indicating that CAMK2N1 may serve as a biomarker. The inhibition of tumor growth by expressing CAMK2N1 established a role of CAMK2N1 as a therapeutic target.


Assuntos
Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Proteínas/genética , Proteínas/metabolismo , Animais , Apoptose/fisiologia , Proliferação de Células/fisiologia , Progressão da Doença , Genes Supressores de Tumor , Xenoenxertos , Humanos , Masculino , Camundongos Nus , Neoplasias de Próstata Resistentes à Castração/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais
12.
Ultrasound Med Biol ; 40(8): 1769-77, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24768485

RESUMO

Ultrasonography (US) is the preferred imaging modality for papillary thyroid microcarcinoma (PTMC). The aim of this study was to evaluate the importance of gray-scale ultrasound combined with elastography to predict extrathyroidal extension and cervical lymph node (LN) metastasis in patients with PTMC. We retrospectively evaluated gray-scale ultrasonic and elastographic results from 119 consecutive cases of PTMC with 138 nodules and correlated the histopathological findings. The results indicated that pathological extrathyroidal extension was significantly associated with T staging on US, extrathyroidal extension on US, bilaterality on US, boundary, strain ratio and hard malignancy as measured with the Rago score. Central LN metastasis on pathology was significantly associated with central LN metastasis on US, lateral LN metastasis on US, multifocality on US and bilaterality on US. Lateral LN metastasis on US was significantly associated with lateral LN metastasis on pathology. On multivariate analysis, T staging on US, extrathyroidal extension on US and hard malignancy as measured with the Rago score were significantly associated with pathological extrathyroidal extension. Lateral LN metastasis on US and bilaterality on US were independent factors in predicting central LN metastasis on pathology. Lateral LN metastasis on US was the predictive factor for lateral LN metastasis on pathology. US should be helpful in the diagnosis of PTMC and in the evaluation of possible PTMC recurrence on US in routine clinical practice.


Assuntos
Carcinoma Papilar/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Linfonodos/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Adolescente , Adulto , Idoso , Carcinoma Papilar/patologia , Criança , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Pescoço , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/patologia , Adulto Jovem
13.
J Appl Toxicol ; 33(11): 1268-76, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22976841

RESUMO

Perfluorooctane sulfonate (PFOS) is a widespread environmental contaminant that is detected in the lung of mammals. The mechanisms underlying PFOS-induced lung cytotoxicity remain unclear. The main purpose of this study was to evaluate the cytotoxic effects of PFOS on human lung cancer A549 cells and its possible molecular mechanism. A549 cells were treated with PFOS (0, 25, 50, 100 and 200 µm) and the cellular apoptosis, mitochondrial membrane potential as well as intracellular reactive oxygen species were determined. In this study, PFOS induced a dose-dependent increase in A549 cell toxicity via an apoptosis pathway as characterized by increased percentage of sub-G1, activation of caspase-3 and -9, and increased ratio of Bax/bcl-2 mRNA expression. In addition, there was obvious oxidative stress, represented by decreased glutathione level, increased malondialdehyde level and superoxide dismutase activity. N-Acetylcysteine, as an antioxidant that is a direct reactive oxygen species scavenger, can effectively block PFOS-induced reactive oxygen species generation, mitochondrial membrane potential loss and cell apoptosis. These data indicate that PFOS induces apoptosis in A549 cells through a reactive oxygen species-mediated mitochondrial dysfunction pathway mechanism.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Apoptose/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Fluorocarbonos/toxicidade , Pulmão/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Pulmão/enzimologia , Pulmão/metabolismo , Pulmão/patologia , Mitocôndrias/enzimologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia
14.
J Endocrinol ; 215(2): 303-11, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22946080

RESUMO

Phenolic estrogen pollutants, a class of typical endocrine-disrupting chemicals, have attracted public attention due to their estrogenic activities of imitating steroid hormone 17ß-estradiol (E(2)) effects. Exposure to these pollutants may disrupt insulin secretion and be a risk factor for type 2 diabetes. In this study, we investigated the direct effects of phenolic estrogen diethylstilbestrol (DES), octylphenol (OP), nonylphenol (NP), and bisphenol A (BPA) on rat pancreatic islets in vitro, whose estrogenic activities were DES>NP>OP>BPA. Isolated ß-cells were exposed to E(2), DES, OP, NP, or BPA (0, 0.1, 0.5, 2.5, 25, and 250 µg/l) for 24 h. Parameters of insulin secretion, content, and morphology of ß-cells were measured. In the glucose-stimulated insulin secretion test, E(2) and DES increased insulin secretion in a dose-dependent manner in a 16.7 mM glucose condition. However, for BPA, NP, or OP with lower estrogenic activity, the relationship between the doses and insulin secretion was an inverted U-shape. Moreover, OP, NP, or BPA (25 µg/l) impaired mitochondrial function in ß-cells and induced remarkable swelling of mitochondria with loss of distinct cristae structure within the membrane, which was accompanied by disruption of mRNA expression of genes playing a key role in ß-cell function (Glut2 (Slc2a2), Gck, Pdx1, Hnf1α, Rab27a, and Snap25), and mitochondrial function (Ucp2 and Ogdh). Therefore, these phenolic estrogens can disrupt islet morphology and ß-cell function, and mitochondrial dysfunction is suggested to play an important role in the impairment of ß-cell function.


Assuntos
Poluentes Ambientais/toxicidade , Estrogênios/toxicidade , Ilhotas Pancreáticas/efeitos dos fármacos , Fenóis/toxicidade , Animais , Diabetes Mellitus Tipo 2 , Masculino , Mitocôndrias/metabolismo , Análise Serial de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Estrogênio/metabolismo , Fatores de Risco
15.
J Nanosci Nanotechnol ; 11(4): 3651-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21776750

RESUMO

In recent years, much attention has been given to liposomal formulation as an efficient drug loading system (DDS) in chemotherapy of cancer. In this study, the advantages of magnetic nanoparticles and Polyethylene Glyco (PEG) materials were considered to synthesize magnetic gemcitabine long-circulating liposomes (MGLL) and the potential of MGLL as a brand new delivery system was evaluated. MGLL was prepared using the reverse-phase evaporation method. In the optimized preparation, MGLL had an average diameter of 201 nm with a narrow size distribution measured by dynamic light scattering (DLS), which could be easily dispersed in ultrapure water under a stable state for 90 days. The encapsulation efficiency of gemcitabine in MGLL reached 87.2% as determined by HPLC. In vitro MTT assay showed that MGLL had significant cytotoxicity to MCF-7 cells compared with the conventional modalities. In vivo, the inhibition of tumor growth in MGLL group was more remarkable than that of other groups (P < 0.05). In conclusion, MGLL under optimized condition could be used as an effective carrier for tumor-targeted therapy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Desoxicitidina/administração & dosagem , Desoxicitidina/química , Teste de Materiais , Ratos , Resultado do Tratamento , Gencitabina
16.
Yao Xue Xue Bao ; 44(2): 181-7, 2009 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-19408690

RESUMO

The magnetic responsibility and antitumor effect of magnetic gemcitabine stealth nano-liposomes (MGSL) on breast cancer cell line MCF-7 in vitro and in vivo was evaluated. The magnetic response and targeting effect of MGSL in vivo were investigated. Morphological feature and ultrastructure changes of apoptosis of MCF-7 cells were observed. The effect of MGSL on proliferation inhibitory rate of MCF-7 cells was measured with MTT method. The FCM analysis was carried out to examine the cell cycle distribution and cell apoptotic rate. The antitumor effect on human breast cancer xenografts in nude mice was also studied. MGSL was able to converge at the targeting tissue under tridimensional magnetic field and the gemcitabine concentration around it increased, while the amount of gemcitabine in other organs decreased, such as in kidneys and heart. MCF-7 cell line was sensitive to MGSL and the cytotoxity was correlated with the loaded drug dose. The effect of MGSL on apoptosis of MCF-7 was obvious and the rate of apoptosis was 51.62%. The growth speed of tumor in the group of MGSL (+) significantly slowed down than that of other groups. MGSL prepared by reverse-phase evaporation method met with the demand of targeted delivery system, and it might be an effective antitumor agent.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Desoxicitidina/análogos & derivados , Magnetismo , Animais , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacocinética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacocinética , Desoxicitidina/farmacologia , Relação Dose-Resposta a Droga , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Lipossomos/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/administração & dosagem , Transplante de Neoplasias , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos , Gencitabina
17.
Int J Pharm ; 295(1-2): 213-9, 2005 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-15848006

RESUMO

This research note demonstrates the simultaneous quantitation of a pharmaceutical active ingredient and three excipients in a simulated powder blend containing acetaminophen, Prosolv and Crospovidone. An experimental design approach was used in generating a 5-level (%, w/w) calibration sample set that included 125 samples. The samples were prepared by weighing suitable amount of powders into separate 20-mL scintillation vials and were mixed manually. Partial least squares (PLS) regression was used in calibration model development. The models generated accurate results for quantitation of Crospovidone (at 5%, w/w) and magnesium stearate (at 0.5%, w/w). Further testing of the models demonstrated that the 2-level models were as effective as the 5-level ones, which reduced the calibration sample number to 50. The models had a small bias for quantitation of acetaminophen (at 30%, w/w) and Prosolv (at 64.5%, w/w) in the blend. The implication of the bias is discussed.


Assuntos
Excipientes/análise , Pós/análise , Acetaminofen/análise , Calibragem , Análise Multivariada , Povidona/análise , Espectroscopia de Luz Próxima ao Infravermelho , Ácidos Esteáricos/análise
19.
J Chromatogr A ; 1046(1-2): 297-301, 2004 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-15387202

RESUMO

A capillary gas chromatographic method using flame ionization detection was developed and validated for the trace analysis (ppm level) of methyl methanesulfonate, ethyl methanesulfonate, and isopropyl methanesulfonate in pharmaceutical drug substance. The method utilizes a megabore capillary column with bonded and crosslinked polyethylene glycol stationary phase. A dissolve-and-injection approach was adopted for sample introduction in a splitless mode. The investigated sample solvents include acetonitrile, ethyl acetate, methylene chloride, 1,2-dichloromethane, and toluene. Aqueous mixtures of acetonitrile and water can also be used as sample solvent. A limit of detection of about 1 microg/g (1 ppm) and limit of quantitation of 5 microg/g (5 ppm) were achieved for the mesylate esters in drug substance samples. The method optimization and validation are also discussed in this paper.


Assuntos
Cromatografia Gasosa/métodos , Metanossulfonato de Etila/análise , Mesilatos/análise , Metanossulfonato de Metila/análise , Preparações Farmacêuticas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
World J Gastroenterol ; 9(12): 2676-80, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14669311

RESUMO

AIM: To evaluate and compare the effect of combined transarterial chemoembolization (TACE) and arterial administration of Bletilla striata (a Chinese traditional medicine against liver tumor) versus TACE alone for the treatment of hepatocellular carcinoma (HCC) in ACI rats. METHODS: Subcapsular implantation of a solid Morris hepatoma 3 924A (2 mm3) in the liver was carried out in 30 male ACI rats. Tumor volume (V1) was measured by magnetic resonance imaging (MRI) on day 13 after implantation. The following different agents of interventional treatment were injected after retrograde catheterization via gastroduodenal artery (on day 14), namely, (A) TACE (0.1 mg mitomycin + 0.1 ml Lipiodol) + Bletilla striata (1.0 mg) (n=10); (B) TACE + Bletilla striata (1.0 mg) + ligation of hepatic artery (n=10), (C) TACE alone (control group, n=10). Tumor volume (V2) was assessed by MRI (on day 13 after treatment) and the tumor growth ratio (V2/V1) was calculated. RESULTS: The mean tumor volume before (V1) and after (V2) treatment was 0.0355 cm3 and 0.2248 cm3 in group A, 0.0374 cm3 and 0.0573 cm3 in group B, 0.0380 cm3 and 0.3674 cm3 in group C, respectively. The mean ratio (V2/V1) was 6.2791 in group A, 1.5324 in group B and 9.1382 in group C. Compared with the control group (group C), group B showed significant inhibition of tumor growth (P<0.01), while group A did not (P>0.05). None of the animals died during implantation or in the postoperative period. CONCLUSION: Combination of TACE and arterial administration of Bletilla striata plus ligation of hepatic artery is more effective than TACE alone in the treatment of HCC in rats.


Assuntos
Quimioembolização Terapêutica , Neoplasias Hepáticas/terapia , Orchidaceae , Fitoterapia , Animais , Terapia Combinada , Modelos Animais de Doenças , Neoplasias Hepáticas/patologia , Masculino , Ratos , Ratos Endogâmicos ACI
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