RESUMEN
A novel nanoscale molecular probe is formulated in order to reduce toxicity and side effects of antitumor drug doxorubicin (DOX) in normal tissues and to enhance the detection sensitivity during early imaging diagnosis. The mechanism involves a specific targeting of Arg-Gly-Asp peptide (RGD)-GX1 heterogeneous dimer peptide-conjugated dendrigraft poly-l-lysine (DGL)-magnetic nanoparticle (MNP) composite by αvß3-integrin/vasculature endothelium receptor-mediated synergetic effect. The physicochemical properties of the nanoprobe were characterized by using transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, dynamic light scattering (DLS), and vibrating sample magnetometer. The average diameter of the resulting MNP-DGL-RGD-GX1-DOX nanoparticles (NPs) was ~150-160 nm by DLS under simulate physiological medium. In the present experimental system, the loading amount of DOX on NPs accounted for 414.4 mg/g for MNP-DGL-RGD-GX1-DOX. The results of cytotoxicity, flow cytometry, and cellular uptake consistently indicated that the MNP-DGL-RGD-GX1-DOX NPs were inclined to target HepG2 cells in selected three kinds of cells. In vitro exploration of molecular mechanism revealed that cell apoptosis was associated with the overexpression of Fas protein and the significant activation of caspase-3. In vivo magnetic resonance imaging and biodistribution study showed that the MNP-DGL-RGD-GX1-DOX formulation had high affinity to the tumor tissue, leading to more aggregation of NPs in the tumor. In vivo antitumor efficacy research verified that MNP-DGL-RGD-GX1-DOX NPs possessed significant antitumor activity and the tumor inhibitory rate reached 78.5%. These results suggested that NPs could be promising in application to early diagnosis and therapy in hepatocellular carcinoma as a specific nanoprobe.
Asunto(s)
Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/tratamiento farmacológico , Dendrímeros/química , Diagnóstico Precoz , Neoplasias Hepáticas/tratamiento farmacológico , Nanopartículas de Magnetita/química , Sondas Moleculares/química , Péptidos/química , Polilisina/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Liberación de Fármacos , Citometría de Flujo , Células Hep G2 , Humanos , Neoplasias Hepáticas/diagnóstico , Imagen por Resonancia Magnética , Nanopartículas de Magnetita/ultraestructura , Masculino , Ratones Endogámicos BALB C , Espectroscopía Infrarroja por Transformada de Fourier , Distribución Tisular/efectos de los fármacos , Receptor fas/metabolismoRESUMEN
A decrease in pyloric myoelectrical activity and pyloric substance P (SP) content following intrasphincteric injection of botulinum toxin type A (BTX-A) in free move rats have been demonstrated in our previous studies. The aim of the present study was to investigate the inhibitory effect of BTX-A on rat pyloric muscle contractile response to SP in vitro and the distributions of SP and neurokinin 1 receptor (NK1R) immunoreactive (IR) cells and fibers within pylorus. After treatment with atropine, BTX-A (10 U/mL), similar to [D-Arg¹, D-Phe5, D-Trp(7,9), Leu(11)]-SP (APTL-SP, 1 µmol/L) which is an NK1R antagonist, decreased electric field stimulation (EFS)-induced contractile tension and frequency, whereas, subsequent administration of APTL-SP did not act on contractility. Incubation with BTX-A at 4 and 10 U/mL for 4 h respectively decreased SP (1 µmol/L)-induced contractions by 26.64% ± 5.12% and 74.92% ± 3.62%. SP-IR fibers and NK1R-IR cells both located within pylorus including mucosa and circular muscle layer. However, fewer SP-fibers were observed in pylorus treated with BTX-A (10 U/mL). In conclusion, BTX-A inhibits SP release from enteric terminals in pylorus and EFS-induced contractile responses when muscarinic cholinergic receptors are blocked by atropine. In addition, BTX-A concentration- and time-dependently directly inhibits SP-induced pyloric smooth muscle contractility.
Asunto(s)
Toxinas Botulínicas Tipo A/farmacología , Contracción Muscular/efectos de los fármacos , Músculo Liso/efectos de los fármacos , Píloro/efectos de los fármacos , Sustancia P/análogos & derivados , Sustancia P/metabolismo , Animales , Estimulación Eléctrica , Técnicas In Vitro , Músculo Liso/metabolismo , Músculo Liso/fisiopatología , Complejo Mioeléctrico Migratorio/efectos de los fármacos , Píloro/metabolismo , Píloro/fisiopatología , Ratas Sprague-Dawley , Sustancia P/farmacologíaRESUMEN
Autophagy is crucial in the maintenance of homeostasis and regenerated energy of mammalian cells. Macroautophagy and chaperone-mediated autophagy(CMA) are the two best-identified pathways. Recent research has found that in normal cells, decline of macroautophagy is appropriately parallel with activation of CMA. However, whether it is also true in cancer cells has been poorly studied. Here we focused on cross-talk and conversion between macroautophagy and CMA in cultured Burkitt lymphoma Raji cells when facing serum deprivation and exposure to a toxic compound, arsenic trioxide. The results showed that both macroautophagy and CMA were activated sequentially instead of simultaneously in starvation-induced Raji cells, and macroautophagy was quickly activated and peaked during the first hours of nutrition deprivation, and then gradually decreased to near baseline. With nutrient deprivation persisted, CMA progressively increased along with the decline of macroautophagy. On the other hand, in arsenic trioxide-treated Raji cells, macroautophagy activity was also significantly increased, but CMA activity was not rapidly enhanced until macroautophagy was inhibited by 3-methyladenine, an inhibitor. Together, we conclude that cancer cells exhibit differential responses to diverse stressor-induced damage by autophagy. The sequential switch of the first-aider macroautophagy to the homeostasis-stabilizer CMA, whether active or passive, might be conducive to the adaption of cancer cells to miscellaneous intracellular or extracellular stressors. These findings must be helpful to understand the characteristics, compensatory mechanisms and answer modes of different autophagic pathways in cancer cells, which might be very important and promising to the development of potential targeting interventions for cancer therapies via regulation of autophagic pathways.
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Antineoplásicos/farmacología , Arsenicales/farmacología , Autofagia/efectos de los fármacos , Chaperonas Moleculares/metabolismo , Óxidos/farmacología , Inanición , Adenina/análogos & derivados , Adenina/farmacología , Trióxido de Arsénico , Linfoma de Burkitt/tratamiento farmacológico , Linfoma de Burkitt/patología , Línea Celular Tumoral , HumanosRESUMEN
Although it is generally acknowledged that auto-phagy plays an important role in tumorigenesis and therapy, studies of autophagy in different cell types and under different conditions have led to conflicting theories regarding the influence of autophagy on cell death. In the present study, we explored the role of autophagy and its underlying mechanism in the inhibitory effects of arsenic trioxide (As2O3) on Burkitt's lymphoma Raji cells. The results showed that As2O3 significantly inhibited the proliferation of Raji cells in a dose- and time-dependent manner, induced G2/M phase cell cycle arrest and apoptosis. Moreover, As2O3 also promoted the formation of autophagic vacuoles, as well as increased the degradation of autophagy substrate P62 protein, which was accompanied by an upregulation of Beclin-1 gene and a downregulation of Bcl-2 gene expression. 3-Methyladenine, an autophagy inhibitor, not only increased cell viability through inhibiting autophagic cell death and apoptosis, but also reversed the upregulation of Beclin-1 gene and the downregulation of Bcl-2 gene in the Raji cells induced by As2O3. These results may lead to a better understanding of the action of As2O3 and may provide evidence that autophagy plays an important role in the regulation of cell death. Therefore, regulation of autophagic activity may be a promising therapy for patients with Burkitt's lymphoma.
Asunto(s)
Antineoplásicos/farmacología , Arsenicales/farmacología , Autofagia/efectos de los fármacos , Linfoma de Burkitt , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Óxidos/farmacología , Adenina/análogos & derivados , Adenina/farmacología , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/metabolismo , Trióxido de Arsénico , Beclina-1 , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Ensayos de Selección de Medicamentos Antitumorales , Genes bcl-2/efectos de los fármacos , Humanos , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Regulación hacia ArribaRESUMEN
BACKGROUND: Botulinum toxin type A (BTX-A) has been reported to be effective for the therapy for migraine. The purpose of this study was to investigate the effect of BTX-A on the immunoreactive levels of calcitonin gene-related peptide (CGRP) and substance P (SP) in the jugular plasma and medulla oblongata of migraine in rats induced by nitroglycerin (NTG), and then to evaluate and compare the effectiveness of fixed (muscle)-sites and acupoint-sites injection of BTX-A for migraine therapy of patients in a randomly controlled trial extending over four months. MATERIALS AND METHODS: Rats with NTG-induced migraine were subcutaneously injected with vehicle or BTX-A (5 U/kg or 10 U/kg bodyweight). CGRP- and SP-like immunoreactivity (CGRP-LI and SP-LI) were determined by radioimmunoassay. In clinical trials, sixty patients respectively received BTX-A (2.5 U each site, 25 U per patient) at fixed-sites (group F, n = 30) including occipitofrontalis, corrugator supercili, temporalis and trapezius or at acupoint-sites (group A, n = 30) including EX-HN3, EX-HN5, GV20, GB8, GB20 and BL10. RESULTS: Local BTX-A injection suppressed NTG-induced CGRP-LI and SP-LI levels in jugular plasma and oblongata. BTX-A injection for both groups with migraine significantly reduced the attack frequency, intensity, duration and associated symptoms. The efficacy of BTX-A for migraine in group A (93% improvement) was more significant than that in group F (83% improvement) (P < 0.01). CONCLUSIONS: The evidence that BTX-A decreases NTG-induced CGRP-LI and SP-LI levels in trigeminovascular system suggests that BTX-A attenuates migraine by suppression of neuropeptide release. BTX-A injections for migraine at acupoint-sites and fixed-sites are effective. Acupoint-sites BTX-A administration shows more efficacy for migraine than fixed-sites application.
RESUMEN
In the title hydroxamic acid derivative, C22H16Cl2N2O5, the nitro-substituted benzene ring forms dihedral angles of 26.95â (15) and 87.06â (15)°, with the 4-chloro- and 2-chloro-substituted benzene rings, respectively. The dihedral angle between the chloro-substituted benzene rings is 68.19â (13)°. The O atoms of the nitro group were refined as disordered over two sets of sites with equal occupancies. In the crystal, weak C-Hâ¯O(=C) hydrogen bonds link mol-ecules along [100].
RESUMEN
OBJECTIVE: To investigate the efficacy of multi-frequency focused ultrasound (MfFU) in the treatment of alveolar hydatid disease in mice. METHODS: Thirty Kunming mice infected subcutaneously with alveolar protoscoleces were divided into 3 groups randomly of 10 mice each and irradiated with different intensity of MfFU. Mice in the experiment groups B and C were irradiated only once for 5 min and group A served as control. The irradiation power of the 3 transducers in the low-power group (group B) was 4 W + 4 W + 5 W; that in the high-power group (group C) was 10 W + 11 W + 10 W. After the irradiation, the morphological change of alveolar tissues was observed with transmission electron microscope. The survival rate of protoscoleces was evaluated with methylene blue staining. The mitochondrial content in the alveolar tissues was detected with laser confocal microscope. The Coomassie brilliant blue staining and succinate dehydrogenase (SDH) kit were applied for measuring the amount of general proteins and the activity of succinate dehydrogenase of the alveolar hydatid cyst respectively. RESULTS: After irradiated by MfFU, transmission electron microscopy showed that in groups B and C the cells on the germinal layer decreased. The mitochondria swelled or broke. The endo cytoplasmic reticulum became swollen markedly. The karyotheca looked unclear. The microvilli shortened or disappeared. All the damages in group C displayed more seriously than in group B. The survival rate of protoscoleces in groups B (70.50%) and C (59.83%) was statistically lower than that of group A (82.33%) (P < 0.05). And there was also a statistical difference between groups B and C (P < 0.05). The amount of general proteins and the activity of SDH in groups B (3.07 mg/ml and 2.15 U/mg respectively) and C (2.87 mg/ml and 1.87 U/mg) were lower significantly than those in group A (3.83 mg/ml and 3.50 U/mg) (P < 0.05), but no statistical difference between B and C (P > 0.05). The mitochondria content in groups B (105.46 a.u/a) and C (70.90 a.u/a) was lower than that in group A (133.45 a.u/a). Group C showed statistical difference than A and B (P < 0.05), but there was no statistical difference between A and B (P > 0.05). CONCLUSION: It is evident that the cysts of Echinococcus multilocularis in mice can be damaged by MfFU which shows certain curative effect.