RESUMEN
RATIONALE: Accurate quantitative analysis of bromine and iodine in serum is an important aspect of monitoring body condition, but the volatile loss of halogen in sample pretreatment is a troublesome problem. We present a validated and flexible high-throughput method for quantification of bromine and iodine in dried serum spots (DSS) using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and an external aqueous standard calibration curve. The influence of serum matrix and laser ablation (LA) conditions on the analysis of bromine and iodine in DSS was researched systematically. METHODS: Aqueous standards without matrix matching were used for calibration to analyze bromine and iodine in serum by LA-ICP-MS. 5-µL volumes of the aqueous standard solution and serum samples in 10 times diluted concentration were deposited on the PTFE paper to form dried standard calibration spots (DSCS) and DSS, of less than 2 mm in diameter. LA was performed using a focused Nd:YAG laser beam in raster lineal scan mode. RESULTS: The limits of detection (LODs) for bromine and iodine in DSS were 0.23 and 0.03 mg L-1 , respectively. The relative standard deviation (RSD) for this method was less than 10%. The samples were also detected with matrix matching calibration by ICP-MS. The accuracy of the method was verified by statistical analysis of these results from ICP-MS and LA-ICP-MS. The accuracy is satisfactory with recoveries ranging from 81.5% to 118%. CONCLUSIONS: A novel and simple approach for high-throughput screening of bromine and iodine in DSS has been established by LA-ICP-MS. Calibration could be achieved using an aqueous standard solution instead of a matrix-matching solution. The method allowed analysis of low-volume biological samples without derivatization and decreased the risk of contamination or loss.
Asunto(s)
Bromo/sangre , Yodo/sangre , Terapia por Láser/métodos , Espectrometría de Masas/métodos , HumanosRESUMEN
Many curcumin derivatives were produced and characterized to improve the physiochemical instability and low solubility of curcumin. Here, MHMM-41 (a novel curcumin derivative) was used to treat non-small lung cancer cells of human (known as A549) and to identify its anti-proliferative activities. Our results suggested that MHMM-41 display no significant cytotoxicity toward normal human lung fibroblast 2BS cells and mouse embryonal fibroblast 3T3 cells. It also had better anti-proliferative activity than curcumin in A549 cells. Further study showed a significant increase of apoptotic A549 cells in time and dose dependent manners. The activation of caspase-3, 8, 9, 12, Bax and PARP proteins were detected. Consequently, MHMM-41 treatment led to the reduction of mitochondrial membrane potential by JC-1 staining and characteristic nuclei fragmentation by Hoechst 33,342 staining, respectively, which showed that A549 apoptosis could be triggered by the extrinsic and intrinsic mitochondrial pathways. The release of ROS was also measured by flow cytometry. Further, wound healing assay and transwell experiments confirmed the anti-migration ability of MHMM-41 in A549 cells. Our current study suggested the potentials of MHMM-41 to inhibit the A549 cell proliferation. However, the intensive mechanical research on the anti-proliferation of A549 cells needs to be performed in the future.
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Apoptosis/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Curcumina/análogos & derivados , Curcumina/farmacología , Neoplasias Pulmonares/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Células 3T3 , Células A549 , Animales , Apoptosis/fisiología , Movimiento Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Curcumina/uso terapéutico , Relación Dosis-Respuesta a Droga , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , RatonesRESUMEN
Oxymatrine is one of the primary natural compounds extracted from the Sophora flavescens, and has been reported to exhibit numerous pharmacological properties including cancerpreventive and anticancer effects, however the mechanisms as to how oxymatrine exhibits antiproliferative activity in nonsmall cell lung carcinoma cells remains uncertain. The present study aimed to explore the mechanism of its anticancer effect, and whether it is due to apoptosis induction and antimigration in the A549 lung cancer cell line. Detection of morphological alterations, MTT analysis, Hoechst/propidium iodide dual staining and terminal deoxynucleotidyl transferase dUTP nick end labeling assays verified that oxymatrine induced A549 cell apoptosis. The caspase paninhibitor zVADFMK resulted in disappearance of oxymatrineelicited nuclei fragmentation via Hoechst 33342 staining. JC1 staining demonstrated a decrease in mitochondrial membrane potential which further verified the induction of apoptosis by oxymatrine. The caspase3, 8 and 9 activities of oxymatrinetreated cells were activated, which suggested that extrinsic and intrinsic apoptotic pathways were involved in the antiproliferative effects of oxymatrine in A549 cells. Furthermore, the wound healing assay verified the antimigratory effects of oxymatrine in A549 cells.
Asunto(s)
Alcaloides/farmacología , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Neoplasias Pulmonares/metabolismo , Quinolizinas/farmacología , Transducción de Señal/efectos de los fármacos , Caspasas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , HumanosRESUMEN
Tet methylcytosine dioxygenase 2 (TET2) mediates the conversion of 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC). The loss of TET2 is associated with advanced atherosclerotic lesions. Our previous study showed that TET2 improves endothelial cell function by enhancing endothelial cell autophagy. Accordingly, this study determined the role of TET2 in atherosclerosis and potential mechanisms. In ApoE-/- mice fed high-fat diet, TET2 overexpression markedly decreased atherosclerotic lesions with uniformly increased level of 5hmC and decreased level of 5mC in genomic DNA. TET2 overexpression also promoted autophagy and downregulated inflammation factors, such as vascular cell adhesion molecule 1, intercellular adhesion molecule 1, monocyte chemotactic protein 1, and interleukin-1. Consistently, TET2 knockdown with small hairpin RNA (shRNA) in ApoE-/- mice decreased 5hmC and increased 5mC levels in atherosclerotic lesions. Meanwhile, autophagy was inhibited and atherosclerotic lesions progressed with an unstable lesion phenotype characterized by large lipid core, macrophage accumulation, and upregulated inflammation factor expression. Experiments with the cultured endothelial cells revealed that oxidized low-density lipoprotein (ox-LDL) inhibited endothelial cell autophagy. TET2 shRNA strengthened impaired autophagy and autophagic flux in the ox-LDL-treated endothelial cells. TET2 overexpression reversed these effects by decreasing the methylation level of the Beclin 1 promoter, which contributed to the downregulation of inflammation factors. Overall, we identified that TET2 was downregulated during the pathogenesis of atherosclerosis. The downregulation of TET2 promotes the methylation of the Beclin 1 promoter, leading to endothelial cell autophagy, impaired autophagic flux, and inflammatory factor upregulation. Upregulation of TET2 may be a novel therapeutic strategy for treating atherosclerosis.