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ABSTRACT: Metabolic alteration in cancer cells is one of the most conspicuous characteristics that distinguish cancer cells from normal cells. Many studies suggest that several underlying mechanisms lead to the Warburg effect (increased aerobic glycolysis) during cancer development. Here, we explored how oroxylin A affected the glycolytic metabolism in cancer cells and the underlying mechanism involved in this process. Our data revealed that both oroxylin A and adriamycin could inhibit lactate generation and glucose uptake in HepG2 cells at mild concentrations, without causing robust cell apoptosis. Oroxylin A has exerted little influence on the oxygen consumption, whereas adriamycin decreased oxygen consumption in a concentration-dependent manner. Moreover, oroxylin A could increase protein and mRNA expression of TP53-induced glycolysis and apoptosis regulator (TIGAR) and synthesis of cytochrome c oxidase 2 (SCO2), which are the key metabolic modulators regulated by p53. Meanwhile adriamycin could increase protein and mRNA expression of TIGAR and SCO2, but decrease that of phosphoglycerate mutase (PGM). Oroxylin A and adriamycin also modulated the stability and activity of p53 through inducing phosphorylation of p53 at Ser15 and suppressing the expression of MDM2. Furthermore, p53 siRNA and p53 inhibitor assay in wild-type p53 HepG2 cells both revealed the key role of p53 in oroxylin A and adriamycin-mediated glycolytic metabolism regulation. Transfecting wt p53 plasmid to p53-deficient H11299 cells could inverse some of the metabolic characteristics regulated by oroxylin A. This study revealed a new aspect of glucose metabolism regulation of oroxylin A, which may contribute to its new anticancer mechanism.
The international journal of biochemistry & cell biology 04/2013; · 4.89 Impact Factor
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ABSTRACT: Abstract Volatile organic compounds (VOCs) are widely used as constituents of household chemicals. Although adverse health effects have been reported, long-term exposure to low-level VOCs mixture has not been studied. Especially, there is a lack of substantial information on the sensitive biomarkers and carcinogenic markers. In the present study, we examined oxidative stress and genotoxic effects of sub-chronic low-dose VOCs mixture (formaldehyde, benzene, toluene and xylene). Male Kunming mice were exposed to 0 (control) and three different doses of VOCs mixture (group 1S, 5S and 10S) for 90 d (2 h/d). Group 1S is 0.10, 0.11, 0.20 and 0.20 mg/m(3), group 5S is 0.50, 0.55, 1.00 and 1.00 mg/m(3), group 10S is 1.00, 1.10, 2.00 and 2.00 mg/m(3), which, respectively, corresponded to 1, 5 and 10 times of indoor air quality standard (IAQS) in China. One day following VOCs exposure, oxidative stress markers in lung, 8-hydroxy-2'-deoxyguanosine in bronchoalveolar lavage fluid and genotoxicity (DNA damage) in liver were examined. Results showed that exposure to VOCs (IAQS dose) resulted in oxidative damages of lung, which were supported by the significant changes on reactive oxygen species, reduced glutathione (GSH), GSH S-transferase, total antioxidative capacity, malondialdehyde, protein carbonyl and nitric oxide (NO). Moreover, oxidative stress markers in group 5S and 10S (except NO) in lung were affected significantly. In addition, VOCs exposure also induced significantly DNA damage in liver. Our study suggested long-term VOCs inhalation at low levels caused oxidative stress and genotoxicity response in mice. Since effects were seen at the current IAQS level, further studies below this level are necessary.
Inhalation Toxicology 04/2013; 25(5):235-42. · 1.92 Impact Factor
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ABSTRACT: Inflammatory lung diseases are characterized by chronic inflammation and oxidant/antioxidant imbalance. Exposure to some kinds of volatile organic compounds (VOCs) leads to lung inflammation, oxidative stress, and immune modulation. However, it is suspected that sub-chronic exposure to low-dose VOCs mixture induces or aggravates lung inflammation. To clarify the effect of this exposure on lung inflammatory responses, 40 male Kunming mice were exposed in four similar static chambers, 0 (control) and three different doses of VOCs mixture (groups 1-3). The concentrations of VOCs mixture were as follows: formaldehyde, benzene, toluene, and xylene 0.10 + 0.11 + 0.20 + 0.20 mg/m(3) , 0.50 + 0.55 + 1.00 + 1.00 mg/m(3) , 1.00 + 1.10 + 2.00 + 2.00 mg/m(3) , respectively, which corresponded to 1, 5, and 10 times of indoor air quality standard in China. After 90 consecutive days of exposure (2 h/day), oxidative stress markers in lung, cellular infiltration and cytokines, chemokine, neurotrophin in bronchoalveolar lavage fluid (BALF), and immunoglobulin (Ig) in serum were examined. VOCs exposure could increase significantly reactive oxygen species (ROS) in lung, the levels of interleukin-8 (IL-8), IL-4, eotaxin, nerve growth factor (NGF), and various types of leukocytes in BALF, IgE concentration in serum. In contrast, GSH to GSSG ratio and interferon-gamma were significantly decreased following the VOCs exposure. These results indicate that the VOCs mixture-induced inflammatory response is at least partly caused by release of the ROS and mediators from the activated eosinophils, neutrophils, alveolar macrophages and epithelial cells. © 2013 Wiley Periodicals, Inc. Environ Toxicol 2013.
Environmental Toxicology 02/2013; · 2.41 Impact Factor
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Xuelian Li, Wei Liu,
Jie Wang,
Dayang Zou,
Xuesong Wang,
Zhan Yang,
Zhitao Yin,
Qian Cui,
Wei Shang,
Huan Li,
Xiao Wei,
Jing Cui,
Zhongquan Wang,
Liuyu Huang,
Jing Yuan
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ABSTRACT: Trichinellaspiralisis a tissue-dwelling nematode parasite. A loop-mediated isothermal amplification (LAMP) assay was developed and validated for the sensitive and rapid detection of T. spiralis larvae in muscle samples. Sixteen sets of primers were designed to recognize distinct sequences of a conserved gene, a 1.6kb repetitive element of the Trichinella genome. One set of primers was selected as the most appropriate for rapid detection. The specificity and sensitivity of the primers in LAMP reactions for T. spiralis larvae and muscle samples of mice infected with T. spiraliswere determined. Another 10 heterologous parasites were selected for specificity assays. The results showed that target DNA was amplified and visualized by monitoring turbidity and adding calcein detection methods within 70 min at an isothermal temperature of 63°C. The sensitivity of LAMP with the detection limit of 362 fg/μl was >10 times higher than that for PCR. The designed primers had a good specificity. No cross-reactivity was found with the DNA of any other parasites. The assay was able to detect T. spiralis in all mouse muscle samples infected with 10 T. spiralis larvae on day 20 p.i. We believe this is the first report regarding the application of the LAMP assay for detection of T. spiralis larvae in muscle samples from experimentally infected mice. This method demonstrates a potentially valuable means for the direct detection of T. spiralis larvae in meat inspection.
International journal for parasitology 11/2012; · 3.39 Impact Factor
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Changlin Shao,
Wei Shang,
Zhan Yang,
Zhongke Sun,
Yunmei Li,
Jing Guo,
Xuesong Wang,
Dayang Zou,
Simiao Wang,
Hong Lei, [......],
Xuelian Li,
Xiao Wei, Wei Liu,
Xiang He,
Zheng Jiang,
Shuangkui Du,
Xiangru Liao,
Liuyu Huang,
Yufei Wang,
Jing Yuan
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ABSTRACT: Bacteria utilize a quorum sensing (QS) system to coordinate gene expression by monitoring the concentration of molecules known as autoinducers (AI). In the present study, we confirmed the presence of a LuxS/AI-2 dependent QS system in vancomycin-resistant Enterococcus faecalis V583. Then, the cellular targets controlled by AI-2 were identified by comparative proteomics analysis in order to elucidate the possible role of AI-2 in E. faecalis. Results demonstrated 15 proteins that are differentially expressed upon the addition of AI-2, including proteins involved in metabolism, translation, energy production and/or conversion, and cell wall biogenesis. Glyceraldehyde-3-phosphate dehydrogenase and malate dehydrogenase associated with carbohydrate metabolism and energy production were up-regulated upon inducing by AI-2. In addition, externally added AI-2 could down-regulate acetyl-coenzyme A carboxylase and ornithine carbamoyltransferase, two key enzyme involved in metabolism. All these data suggest that AI-2 signaling may play a role in the regulation of a number of important metabolic properties of E. faecali. We further investigated the role of AI-2 in biofilm formation by E. faecalis, showing the addition of AI-2 to E. faecalis V583 cultures resulted in increased biofilm formation. Our results provide important clues to the role of a LuxS/AI-2 dependent QS system in vancomycin-resistant E. faecalis.
Journal of Proteome Research 08/2012; 11(9):4465-75. · 5.11 Impact Factor
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ABSTRACT: We report here a narrowband high-spectral resolution sodium temperature/wind lidar recently developed at the University of Science and Technology of China (USTC) in Hefei, China (31.5 °N, 117 °E). Patterned after the Colorado State University (CSU) narrowband sodium lidar with a dye laser-based transmitter, the USTC sodium temperature/wind lidar was deployed with a number of technical improvements that facilitate automation and ease of operation; these include a home constructed pulsed dye amplifier (PDA), a beam-steering system, a star-tracking program, and an electronic timing control. With the averaged power of ∼1.2 W output from PDA and the receiving telescope diameter of 0.76 m, our lidar system has a power aperture product of ∼0.55 Wm(2) and is comparable to the CSU and the University of Illinois at Urbana-Champaign (UIUC) sodium lidar systems. The uncertainties of typical measurements induced by photon noise and laser locking fluctuation for the temperature and wind with a 2 km vertical and 15 min temporal resolutions under the nighttime clear sky condition are estimated to be ∼1.0 K and ∼1.5 m/s, respectively, at the sodium peak (e.g., 91 km), and 8 K and 10 m/s, respectively, at both sodium layer edges (e.g., 81 km and 105 km). The USTC narrowband sodium lidar has been operated regularly during the night since November 2011. Using the initial data collected, we demonstrate the reliability and suitability of these high resolution and precision datasets for studying the wave perturbations in the mesopause region.
Applied Optics 08/2012; 51(22):5401-11. · 1.41 Impact Factor
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ABSTRACT: Autophagy is a tightly-regulated catabolic process that involves the degradation of intracellular components via lysosomes. Although the pivotal role of autophagy in cell growth, development, and homeostasis has been well understood, its function in cancer prevention and intervention remains to be delineated. The aim of this study was to investigate the function and mechanism of autophagy induced by oroxylin A, a natural mono-flavonoid extracted from Scutellariae radix. We found for the first time that oroxylin A induced Beclin 1-mediated autophagy in human hepatocellular carcinoma HepG2 cells. Time-lapse video microscopy and western blotting studies showed that treatment of cells with 80 μM oroxylin A resulted in the conversion of water soluble MAP-LC3 (LC3-I) to the lipidated and autophagosome-associated form (LC3-II) after 12hours; then autophagosome-lysosome fusion and lysosome degradation after 24 hours was required in oroxylin A-mediated cell death. This induction was associated with the suppressing of PI3K-PTEN-Akt-mTOR signaling pathway by oroxylin A. Our results also showed that autophagy took place before noticeable apoptosis can be observed. It was further demonstrated that oroxylin A-triggered autophagy contributed to cell death using over-expression of autophagy-related gene (Atg5 and Atg7) and inhibition of autophagy by siBeclin 1 and 3-methyladenine (3-MA). In vivo study, oroxylin A inhibited xenograft tumor growth and induced obvious autophagy in tumors. Taken together, we conclude that oroxylin A exhibits autophagy-mediated antitumor activity in a dose and time-dependent manner in vivo and in vitro. These findings define and support a novel function of autophagy in promoting death of hepatocellular carcinoma cells.
Cellular signalling 04/2012; 24(8):1722-32. · 4.09 Impact Factor
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ABSTRACT: Volatile organic compounds (VOCs) are the main substances causing multiple chemical sensitivity reactions in human. The effects of single VOCs exposure on airway inflammatory responses in mice lung have been reported. Previous studies have demonstrated the role of reactive oxygen species (ROS) in lung inflammation induced by single VOCs inhalation. However, effects of VOCs exposure on NO signaling and neurological signaling pathways in airway remain less clear. We exposed male Kunming mice to filtered air (0) and four types of VOCs mixture (formaldehyde, benzene, toluene, and xylene) treated air. Group 1 is 1.0, 1.1, 2.0 and 2.0 mg/m(3), group 2 is 3.0, 3.3, 6.0 and 6.0 mg/m(3), group 3 is 5.0, 5.5, 10.0 and 10.0 mg/m(3), group 4 is 10.0, 11.0, 20.0 and 20.0 mg/m(3), which respectively corresponded to 10, 30, 50 and 100 times of indoor air quality standard in China 2 hr per day, 5 days per week, for 2 weeks in the whole body exposure chamber. One day following VOCs exposure, we collected lung, bronchoalveolar lavage fluid (BALF) from each mouse and examined oxidative stress markers, cellular infiltration and production of cytokines, neurotrophin and substance P. We found that VOCs exposure influenced significantly NOS activity, GSH, or IL-6 concentration. The number of total cells, macrophages and eosinophils increased significantly in group 4. In addition, the production of interferon-gamma (IFN-γ) and substance P were significantly decreased. In contrast, neurotrophin-3 production in BALF was significantly increased in group 3 and 4. Our findings suggest that NO signaling pathways may induce airway inflammatory in short term VOCs exposure mice and the airway inflammatory response may be modulated by neurological signaling.
The Journal of Toxicological Sciences 01/2012; 37(4):739-48. · 1.52 Impact Factor
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ABSTRACT: We recently established that LYG-202, a new flavonoid with a piperazine substitution, exerts an anti-tumor effect in vivo and in vitro. In the present study, we demonstrate that LYG-202 induces G1/S phase arrest and apoptosis in human colorectal carcinoma HCT-116 cells. Data showed that the blockade of the cell cycle was associated with increased p21(WAF1/Cip1) and Rb levels and reduced expression of cyclin D1, cyclin E, and CDK4. Moreover, PARP cleavage, activation of caspase-3, caspase-8, and caspase-9, and an increased ratio of Bax/Bcl-2 were detected in LYG-202-induced apoptosis. Additionally, activation of p53 resulted in the up-regulation of its downstream targets PUMA and p21(WAF1/Cip1), as well as the down-regulation of its negative regulator MDM2, suggesting that the p53 pathway may play a crucial role in LYG-202-induced cell cycle arrest and apoptosis. Furthermore, siRNA knockdown of p53 attenuated the G1 cell cycle arrest and apoptosis induced by LYG-202, as the effects of LYG-202 on up-regulation of p21(WAF1/Cip1) and down-regulation of Bcl-2 and pro-caspase-3 were partly inhibited in p53 siRNA transfected cells compared with control siRNA transfected cells. Collectively, these data indicate that LYG-202 exerts its anti-tumor potency by activating the p53-p21 pathway for G1/S cell cycle arrest and apoptosis in colorectal cancer cells.
Biochemistry and Cell Biology 04/2011; 89(3):287-98. · 2.67 Impact Factor
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ABSTRACT: We recently established that NCPMF-60, a newly synthesized flavonoid, is an active cytotoxic component. The molecular mechanisms by which NCPMF-60 exerts its cytotoxic activity are currently unknown. In this study, we show that NCPMF-60 induces G2/M phase arrest and apoptosis in human hepatocellular carcinoma HepG2 cells. After treatment of HepG2 cells with NCPMF-60, cell cycle-related proteins, such as cyclin B1, cyclin H, CDK7, and p-CDK1 (Thr161), were downregulated, whereas p21 and p-CDK1 (Thr14/Tyr15) were upregulated. The activity of CDK1/cyclinB complex was also inhibited by NCPMF-60. In addition, we observed poly(ADP-ribose) polymerase cleavage and activation of caspase 3 and caspase 9. The expression ratio of Bax/Bcl-2 was increased in the treated cells, in which Bax was also upregulated. We also found that the expression of p53 and its phosphorylation at Ser15 accumulated after the treatment of NCPMF-60. Moreover, upregulation of p21, p53-upregulated modifier of apoptosis, and Bax, three p53-target gene products, and the downregulation of Bcl-2 and MDM2, were observed in NCPMF-60-treated cells. However, p53 is not the only regulator in the stimulation of NCPMF-60 on p21 transcriptional level and posttranscriptional level. These results suggested that NCPMF-60 indeed activated the p53 pathway, which may contribute to its induction of cell cycle arrest and apoptosis in HepG2 cells. Collectively, our findings show that cell cycle arrest and apoptosis induced by NCPMF-60 was associated with the activation of p53 pathway and the inhibition of CDK-activating kinase activity in HepG2 cells.
Anti-cancer drugs 01/2011; 22(1):46-57. · 2.23 Impact Factor
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ABSTRACT: Wogonin, a naturally occurring flavonoid, has been shown to have tumor therapeutic potential both in vitro and in vivo. To better understand its anticancer mechanism, we examined the effect of wogonin on human cervical carcinoma HeLa cells. In this study, we observed that G1 phase arrest was involved in wogonin-induced growth inhibition in HeLa cells. Over a 24 h exposure of HeLa cells to 90 micromol x L(-1) wogonin, the promoters of G1-S transition, including cyclin D1/Cdk4 and pRb, decreased within 12 h and E2F-1 depleted in the nucleus at the same time. As the G1 phase arrest developed, p53 and the Cdk inhibitor p21Cip1 elevated both at protein and mRNA levels. Furthermore, the up-regulation of p21Cip1 induced by wogonin was dramatically inhibited by siRNA-mediated p53 gene silencing. Collectively, our data suggested that wogonin induced G1 phase arrest in HeLa cells by modulating several key G1 regulatory proteins, such as Cdk4 and cyclin D1, as well as up-regulation of a p53-mediated p21Cip1 expression. This mechanism of wogonin may play an important role in the killing of cancerous cells and offer a potential mechanism for its anticancer action in vivo.
Biochemistry and Cell Biology 12/2009; 87(6):933-42. · 2.67 Impact Factor
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Ying Gao,
Na Lu,
Yun Ling,
Yan Chen,
Ling Wang,
Qing Zhao,
Qi Qi, Wei Liu,
Haiwei Zhang,
Qidong You,
Qinglong Guo
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ABSTRACT: In this study, we examined the antiangiogenic effect of oroxylin A in vitro and in vivo and explored the potential mechanisms for this effect.
Transwell assay and tube formation assay were used to evaluate the effects of oroxylin A on vascular endothelial growth factor (VEGF)-induced migration and tube formation of human umbilical vein endothelial cells (HUVECs). Rat aortic ring assay was also employed to assess the effect of oroxylin A on microvessel outgrowth from rat aorta. Human tumor xenografts model in nude mice was further used to investigate the antiangiogenic activity of oroxylin A in vivo. Western blot analysis was used to investigate the related mechanism.
Oroxylin A remarkably suppressed the VEGF-stimulated migration and tube formation of HUVECs. It also inhibited microvessel sprouting from rat aortic ring in vitro. In addition, it suppressed the angiogenesis of xenograft tumor in nude mice, which concurred with the inhibition of tumor growth. Moreover, oroxylin A blocked VEGF-induced phosphorylation of KDR/Flk-1 and related downstream signaling molecules, including p38 mitogen-activated protein kinase, extracellular signal-regulated kinase and Akt.
Oroxylin A possessed antiangiogenic activities in vitro and in vivo, which could be an underlying mechanism of its anticancer effect.
Journal of Cancer Research and Clinical Oncology 11/2009; 136(5):667-75. · 2.56 Impact Factor
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Shi Zeng, Wei Liu,
Fei-Fei Nie,
Qing Zhao,
Jing-Jing Rong,
Jia Wang,
Lei Tao,
Qi Qi,
Na Lu,
Zhi-Yu Li,
Qing-Long Guo
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ABSTRACT: LYG-202 is a newly synthesized flavonoid with a piperazine substitution. We investigated the antitumor effect of LYG-202 in vivo and in vitro. We show that, LYG-202 significantly decreases tumor growth in mice inoculated with S180 sarcoma cells, compared with the control group. Meanwhile, the viabilities of various kinds of tumor cells were inhibited by LYG-202 with IC(50) values in the range of 4.80 to 27.70 microM. Then apoptosis induced by LYG-202 in HepG2 cells was characterized by DAPI staining and Annexin V/PI double staining and degradation of PARP was observed. Activation of the caspase cascade for both the extrinsic and intrinsic pathways was demonstrated, including caspase-8, -9, and -3. The results also showed that the expression of Bcl-2 protein decreased whereas that of Bax protein increased, leading to an increase of the Bax/Bcl-2 ratio. Our results demonstrated that LYG-202 exhibited strong antitumor effect in vivo and in vitro, involving with apoptosis induction.
Biochemical and Biophysical Research Communications 09/2009; 385(4):551-6. · 2.48 Impact Factor
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ABSTRACT: Oroxylin A, a naturally occurring monoflavonoid extracted from Scutellariae radix, exhibits anticancer activity and induces apoptosis in human hepatocellular carcinoma HepG2 cells according to our previous data. In this study, we investigate whether p53 is involved in oroxylin A-triggered viability inhibition and apoptosis induction in cancer cells. In a panel of different cancer cell lines, more potent inhibitory effects of oroxylin A were observed in wtp53 cells than those in mtp53 or p53-null cells. Moreover, p53-siRNA-transfected HepG2 cells showed lower levels of apoptosis induced by oroxylin A than control-siRNA-transfected cells. Likewise, after oroxylin A treatment, p53-null K-562 cells displayed promoted apoptosis rate when transfected with wtp53 plasmid. Western blot and real-time RT-PCR assay revealed that oroxylin A markedly upregulated p53 protein expression in HepG2 and p53-overexpressing K-562 cells, but had no influence on p53 mRNA synthesis. Furthermore, after co-treatment with cycloheximide, oroxylin A still exerted a little effect on p53 expression. The negative regulator of p53, MDM2 protein was detected, and downregulated expression was observed. In the presence of MG132, an inhibitor of proteasome-mediated proteolysis, no change in p53 expression was obtained. Additionally, the antioxidant N-acetyl-L-cysteine could obviously abrogate p53 stabilization triggered by oroxylin A. Therefore, it is summarized that oroxylin A stabilized p53 expression and induced apoptosis at the posttranslational level via downregulating MDM2 expression and interfering MDM2-modulated proteasome-related p53 degradation. This indicated that oroxylin A could be served as a potential, novel agent candidate for cancer therapy.
Molecular Carcinogenesis 08/2009; 48(12):1159-69. · 3.16 Impact Factor
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ABSTRACT: It is reported that gambogic acid (GA), the main active compound of gamboge which is a dry resin extracted from Garcinia hanburyi tree, has potent antitumor activity both in vivo and in vitro. Activation of mitochondrial apoptotic pathway in cancer cells is one effective therapy for cancer treatment. In the present study, we focus on the effect of GA on induction of reactive oxygen species (ROS) accumulation and triggering the mitochondrial signaling pathway in human hepatoma SMMC-7721 cells. The results indicated that GA induced ROS accumulation and collapse of mitochondrial membrane potential in SMMC-7721 cells in a concentration-dependent manner and subsequently induced that release of Cytochrome c and apoptosis-inducing factor from mitochondria to cytosol, which inhibited ATP generation and induced apoptosis in the cells. Moreover, GA elevated the phosphorylation of c-Jun-N-terminal protein kinase (JNK) and p38, which was the downstream effect of ROS accumulation. Furthermore, N-acetylcysteine, a ROS production inhibitor, partly reversed the activation of JNK and p38 and the induction of apoptosis in GA-treated cells. Collectively, our study demonstrated that accumulation of ROS played an important role in GA-induced mitochondrial signaling pathway, which provided further theoretical support for the application of GA as a promising anticancer agent.
Toxicology 07/2009; 260(1-3):60-7. · 3.68 Impact Factor
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Yan Chen,
Na Lu,
Yun Ling,
Ying Gao,
Ling Wang,
Yu Sun,
Qi Qi,
Feng Feng,
Wenyuan Liu, Wei Liu,
Qidong You,
Qinglong Guo
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ABSTRACT: Wogonoside, one flavonoid derived from the root of Scutellaria baicalensis Georgi, has been reported for its anti-inflammation activity; however, whether it can inhibit inflammation-induced angiogenesis is still unclear. In the present study, we evaluated the effect of wogonoside on lipopolysaccharide (LPS)-induced angiogenesis in vitro and in vivo. Wogonoside suppressed the LPS-stimulated migration and tube formation of human umbilical vein endothelial cells (HUVECs), as well as microvessel sprouting from rat aortic rings in vitro. Moreover, wogonoside also inhibited LPS-stimulated vessel growth of Chicken chorioallantoic membrane (CAM) in vivo. The mechanism revealed that wogonoside inhibited LPS-induced toll-like receptor 4 (TLR4) up-regulation and its downstream mitogen-activated protein kinases (MAPKs) activation, by decreasing the phosphorylation of c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and p38 mitogen-activated protein kinase. The results suggest that wogonoside inhibits LPS-induced angiogenesis both in vitro and in vivo, and that it might have a therapeutic potential for the diseases associated with the development of both inflammation and angiogenesis progress.
Toxicology 06/2009; 259(1-2):10-7. · 3.68 Impact Factor
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Wei Liu,
Rong Mu,
Fei-Fei Nie,
Yong Yang,
Jun Wang,
Qin-Sheng Dai,
Na Lu,
Qi Qi,
Jing-Jing Rong,
Rong Hu,
Xiao-Tang Wang,
Qi-Dong You,
Qing-Long Guo
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ABSTRACT: Oroxylin A is a flavonoid isolated from the root of Scutellaria baicalensis Georgi. Our previous work demonstrated that the anti-tumor activity of oroxylin A was mainly attributed to its apoptosis inducing effect in cells. The present study explores the exact molecular mechanism of oroxylin A-induced apoptosis in tumor cells. We showed that oroxylin A-induced apoptosis in HepG2 cells was achieved through mitochondrial pathway. We also investigated which mitochondrial channels, PTP or MAC or both, were involved in the permeabilization of the mitochondrial outer membrane after treatment with oroxylin A. The results showed that oroxylin A-induced apoptosis in a PTP-independent manner; therefore, we focused our attention on MAC. As Bax is an essential constituent of MAC in certain systems, we examined the activation, subcellular location, oligomeric structure of Bax in HepG2 cells treated with oroxylin A. Moreover, our results showed that overexpression of Bcl-2 inhibited oroxylin A-induced apoptosis. In summary, we have demonstrated that opening of MAC, but not PTP, played a key role in oroxylin A-induced activation of mitochondrial apoptotic pathway in HepG2 cells.
Cancer letters 06/2009; 284(2):198-207. · 4.86 Impact Factor
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ABSTRACT: We recently established that asparanin A, a steroidal saponin extracted from Asparagus officinalis L., is an active cytotoxic component. The molecular mechanisms by which asparanin A exerts its cytotoxic activity are currently unknown. In this study, we show that asparanin A induces G(2)/M phase arrest and apoptosis in human hepatocellular carcinoma HepG2 cells. Following treatment of HepG2 cells with asparanin A, cell cycle-related proteins such as cyclin A, Cdk1 and Cdk4 were down-regulated, while p21(WAF1/Cip1) and p-Cdk1 (Thr14/Tyr15) were up-regulated. Additionally, we observed poly (ADP-ribose) polymerase (PARP) cleavage and activation of caspase-3, caspase-8 and caspase-9. The expression ratio of Bax/Bcl-2 was increased in the treated cells, where Bax was also up-regulated. We also found that the expression of p53, a modulator of p21(WAF1/Cip1) and Bax, was not affected in asparanin A-treated cells. Collectively, our findings demonstrate that asparanin A induces cell cycle arrest and triggers apoptosis via a p53-independent manner in HepG2 cells. These data indicate that asparanin A shows promise as a preventive and/or therapeutic agent against human hepatoma.
Biochemical and Biophysical Research Communications 05/2009; 381(4):700-5. · 2.48 Impact Factor
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Lei Qiang,
Yong Yang,
Yan-Jun Ma,
Fei-Hong Chen,
Ling-Bo Zhang, Wei Liu,
Qi Qi,
Na Lu,
Lei Tao,
Xiao-Tang Wang,
Qi-Dong You,
Qing-Long Guo
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ABSTRACT: To identify and compare the features of stem like cells in human glioblastoma cell lines U251, U87MG, A172 with primary cultured glioblastoma stem cells, the ratio of CD133+ cells, the ability of tumor sphere formation, and self-renewing capacity of U251, U87MG, A172 cells in serum free medium plus EGF, bFGF and B27 supplement were detected. The results suggested that there might be more cancer stem like cells in U251 cells compared with others. CD133+ cells enriched in SP cells and in U251 cells cultured with the serum free medium. They expressed the neural stem cell markers CD133 and Nestin, but lacked of neuronal and astrocyte marker MAP2, beta-III tubulin and GFAP. They could apparently generate both neurons and glial cells after serum retrieved in vitro. Gli1, Bmi1, Notch2 and PTEN were also found expressed highly in them. Moreover, CD133+ cells were more resistant to hypoxia, irradiations and some chemotherapeutics than CD133-cells. So we suggested that glioblastoma stem like cells were existed in CD133+ cells in U251 cell line with characteristics of self-renew and generation of an unlimited progeny of non-tumorigenic cells. Molecular and functional characterization of such a tumorigenic population may be exploited in the development of novel cancer therapeutic drugs.
Cancer letters 03/2009; 279(1):13-21. · 4.86 Impact Factor
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ABSTRACT: Oroxylin A is a flavonoid that is found in the roots of Scutellaria baicalensis Georgi. Here, we investigated the antitumor effect of oroxylin A in human cervical cancer HeLa cell line in vitro and in vivo. We found that after inoculated with the HeLa cells the mice treated with oroxylin A showed a significant decrease of tumor volumes and tumor weight compared with the control. Meanwhile, the growth inhibition of oroxylin A on HeLa cells were observed by MTT assay and the value of IC(50) was 19.4+/-0.7 microM after treatment for 48h. Upon our previous research, the inhibition by oroxylin A might be through apoptosis. Then apoptosis induced by oroxylin A in HeLa cells was characterized by DAPI staining and Annexin V/PI double staining, and degradation of PARP (poly-ADP-ribose polymerase) was both found in HeLa cells and tumor tissue. Next, activation of the caspase cascade for both the extrinsic and intrinsic pathways were demonstrated in vivo and in vitro, including caspase-8, -9 and -3. We also found that the expression of Bcl-2 protein decreased, which leading to an increase of the Bax/Bcl-2 ratio. Our results showed that oroxylin A exhibited strong antitumor effect in HeLa cell line and apoptosis induction involved in it.
Toxicology 01/2009; 257(1-2):80-5. · 3.68 Impact Factor
