Ming-Gang Bi

Peking Union Medical College Hospital, Peping, Beijing, China

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Publications (5)10.13 Total impact

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    Rong Ma · Ming-Gang Bi · Xiao-Lan Cui
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    ABSTRACT: Murine xenotropic leukemia virus-related virus (XMulV) is used as a model virus in the evaluation of viral inactivation in Chinese hamster ovary (CHO) cell-derived pharmaceutical proteins. Mus dunni cells and mink lung cells are used to produce XMulV particles. In consideration of the characteristics of XMulV, we tried to propagate the viruses on CHO cells, a nonmurine cell line. The viruses were harvested from CHO cells from Day 2 to Day 7 postinfection, and reverse transcription-quantitative polymerase chain reaction was performed to quantify the viruses on different days. A cell-based infectivity assay was used to evaluate the XMulV titers. The content of the XMulV virions began to increase on Day 5 and grew exponentially from Day 6 to Day 7 postinfection. The growth curve was a typical single-step growth curve. Titers of the viral stock harvested on Day 7 were assayed on PG-4 cells, and the titers were 8.78 ± 0.25 log10 PFU/mL. Based on these data, we conclude that CHO cells could be a host cell line for XMulV particles. XMulV produced on Day 7 in CHO cells could be used at a laboratory scale for the evaluation of XMulV clearance in pharmaceutical proteins derived from CHO cells.
    Full-text · Article · Oct 2013 · Journal of the Chinese Medical Association
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    ABSTRACT: Ethnopharmacological relevance: Numerous efforts have been conducted in searching for effective agents against cancer, in particular from herbal medicines. Justicia procumbens is a traditional herbal remedy which was produced in the south-western and southern provinces of China and Taiwan province used to treat fever, pain, and cancer. Here, we identified a new compound 6'-hydroxy justicidin A (JR6) from Justicia procumbens, which showed obvious anti-cancer effects. Materials and methods: The cytotoxicity activity was assayed using MTT and SRB. Intracellular ROS visualization and quantification were acquired by using a laser scanning confocal microscopy. Apoptosis was measured using a propidium iodide (PI) apoptosis detection kit by flow cytometry. Activation of caspases (caspase-3, caspase-8, and caspase-9) was evaluated respectively using GloMax luminescence detector and Caspase-Glo 3,8,9 assay kits. Loss of mitochondrial membrane potential was observed by microscopy using JC-1 dye. Quantitative real-time PCR analysis was employed to detect the expression of protein associated with cell death. Results: JR6 remarkably inhibited growth in human bladder cancer EJ cells by decreasing cell proliferation, reduced the SOD activity, increased the content of reactive oxygen species (ROS), and induced apoptosis. Activation of caspase-8, caspase-9, and the subsequent activation of caspase-3 indicated that JR6 may be inducing intrinsic and extrinsic apoptosis pathways. Caspase-3, caspase-8, and caspase-9 inhibition rendered this extract ineffective, thus JR6-induced apoptosis is caspase-dependent. JR6 also disrupted the mitochondrial membrane potential (Δψm) and unregulated the Bax and p53 expressions in EJ cells. Conclusion: These observations suggest that JR6 induce apoptosis through caspase-dependent pathway in human bladder cancer EJ cells, emphasizing the importance of this traditional medicine and thus presents a potential novel alternative to bladder cancer therapy.
    No preview · Article · Sep 2012 · Journal of ethnopharmacology
  • Source
    Xiao-Li He · Yue-Hua Wang · Ming-Gang Bi · Guan-Hua Du
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    ABSTRACT: Chronic cerebral hypoperfusion, induced by permanent occlusion of bilateral common carotid arteries (2VO), is related to neurological disorders and contributes to cognitive decline. Chrysin (5,7-dihydroxyflavone) is an important member of the flavonoid family. The aim of this study is to investigate the effects of chrysin on cognitive deficits and brain damage in this rat 2VO model. At 52days after ligation, the escape latency in Morris water maze was significantly increased in rats subjected to 2VO, the neuronal damage was also increased accompanied by a large proliferation in glial fibrillary acidic protein (GFAP) immunoreactivity with marked white matter lesions, and neuronal cell apoptosis, all of which were significantly alleviated by long treatment of chrysin (30mg/kg). Biochemical examinations revealed that chrysin decreased lipid peroxide, reduced the increased activities of superoxide dismutase, and attenuated the decreased activities of glutathione peroxidase in 2VO rats. The results suggest that chrysin may have therapeutic potential for the treatment of neurodegeneration and dementia caused by decreased cerebral blood flow, which is most likely related, at least in part, to its anti-inflammatory and antioxidant properties.
    Full-text · Article · Apr 2012 · European journal of pharmacology
  • Lu Xiong · Ming-Gang Bi · Song Wu · Yuan-Feng Tong
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    ABSTRACT: The first total synthesis of 6'-hydroxyjusticidin A, isolated from Justicia procumbens L. with good inhibitory activity against cancer cells, has been accomplished. The structure was confirmed by ¹H NMR, ¹³C NMR, and HR-ESI-MS. The key steps involved a Diels-Alder cycloaddition reaction and a reduction in NaBH₄.
    No preview · Article · Apr 2012 · Journal of Asian natural products research
  • Xiao-Li He · Wei-Qin Zhou · Ming-Gang Bi · Guan-Hua Du
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    ABSTRACT: The senescence-accelerated mouse prone 8 (SAMP8) is a novel aging model characterized by early onset and rapid advancement of senescence. In the present study, 6-month-old male SAMP8 mice were orally administered icariin (75, 150mg/kg) for 15weeks. Mice were submitted to passageway water maze test and step-down passive avoidance test for evaluating cognitive impairments. The HPLC-EC technique was used to determine the monoamine contents in the brain. The effects of icariin on oxidative stress and the acetylcholinesterase (AChE) activity of SAMP8 mice were also investigated. We found that icariin treatment significantly prevented learning and memory impairments of SAMP8 mice in passageway water maze test and step-down test. Icariin could partly reverse alterations of monoamines and metabolites levels in the cortex and hippocampus of SAMP8 mice. Furthermore, icariin-treated SAMP8 mice had significantly decreased malondialdehyde (MDA), nitric oxide (NO) contents, lowered nitric oxide synthase (NOS) activity and higher glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities in the brain homogenates and serum. Meanwhile, the acetylcholinesterase activity was markedly inhibited after icariin administration. However, the positive control piracetam did not show significant beneficial effects. In conclusion, the present findings demonstrated that the improvement of icariin on cognitive impairments in SAMP8 mice may be due to increasing monoamines levels, inhibiting oxidative damage and decreasing acetylcholinesterase activity.
    No preview · Article · Apr 2010 · Brain research