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L. Xu S. S. He D. Y. Li C. Mei X. L. Hou L. S. Jiang F. H. Liu 《Molecular Biology》2016,50(2):270-277
In order to investigate the mechanism of apoptosis in rat intestinal epithelial cells (IEC-6) induced by hydrogen peroxide (H2O2), IEC-6 cells were subjected to 20 μmol/L H2O2 and cell proliferation activity was determined using 3-(4,5-dimethyl-2-yl)-2,5-diphenyltetrazolium bromide. Cell morphology was observed by microscopy and cell apoptosis was detected by acridine orange and ethidium bromide staining and the portion of apoptotic cells was measured by flow cytometry. Genes and proteins related to cell apoptosis were detected by RT-PCR and Western blotting, and the mitochondrial membrane potential was evaluated by fluorescence probes. Results: Significant morphology damage was caused by exposure to H2O2, and results showed that ROS generation significantly increased (P < 0.01). The activity of superoxide dismutase decreased significantly (P < 0.05), malondialdehyde content increased (P < 0.05), and expression of both catalase and glutathione peroxidase decreased significantly (P < 0.05) in the H2O2 treatment group. Mitochondrion membrane potential was reduced, cytochrome released into the cytoplasm and caspase-9 and caspase-3 were significantly increased (P < 0.01) after treatment with H2O2. Moreover, the ratio of Bax/Bcl-2 and apoptosis were significantly increased (P < 0.01) in the H2O2 group. In conclusion, the present study indicated that the mitochondrial pathway plays a vital role in H2O2 induced IEC-6 cell apoptosis. 相似文献
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Lukuan Hou Shuyao Wang Huiming Huang Huayue Li Wei Wang Wenli Li 《Bioorganic & medicinal chemistry letters》2018,28(17):2865-2868
Heterologous expression of the type III polyketide synthase (PKS) gene vioA in marine-derived Streptomyces youssoufiensis OUC6819 led to production of six violapyrones (VLPs), including four novel compounds VLPs Q–T (1–4) and two known compounds VLPs B and I (5 and 6). The structures of 1–4 were elucidated by a combination of spectroscopic analyses, including HR-ESIMS and 1D and 2D NMR data, demonstrating that 1–4 are novel VLPs which are methylated at 4-OH with their corresponding non-methylated counterparts to be VLP A, 5 and 6 and VLP C, respectively. Anti-influenza A [H1N1 (A/Virginia/ATCC1/2009) and H3N2 (A/Aichi/2/1968)] virus activity of compounds 1–6 as well as VLPs A and C were then evaluated using ribavirin as a positive control (IC50?=?66.7 and 99.6?μM). The results revealed that these VLPs showed considerable anti-H1N1 and anti-H3N2 activities with IC50 values of 30.6–132.4?μM and 45.3–150.0?μM, respectively. Notably, all the methylated VLPs displayed better anti-virus activity than their non-methylated counterparts, among which compound 3 (VLP S) exhibited the best activities. Interestingly, methylation at 4-OH has negative effect on the anti-MRSA (methicillin-resistant Staphylococcus aureus) activity instead, with methylated VLPs displaying decreased (2) or abolished (3 and 4) activities in comparison with each of their non-methylated counterparts. 相似文献
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Meng Hou Jinjin Cui Jingjin Liu Fang Liu Rui Jiang Kai Liu Yongshun Wang Li Yin Wenhua Liu Bo Yu 《PloS one》2014,9(1)
Angiopoietin-like 4 (ANGPTL4) is a potential anti-apoptotic agent for various cells. We examined the protective effect of ANGPTL4 on hypoxia/serum deprivation (SD)-induced apoptosis of MSCs, as well as the possible mechanisms. MSCs were obtained from rat bone marrow and cultured in vitro. Apoptosis was induced by hypoxia/SD for up to 24 hr, and assessed by flow cytometry and TUNEL assay. Expression levels of Akt, ERK1/2, focal adhesion kinase (FAK), Src, Bcl-2, Bax, cytochrome C and cleaved caspase-3 were detected by Western blotting. Integrin β1 mRNA was detected by qRT-PCR. Mitochondrial membrane potential was assayed using a membrane-permeable dye. Hypoxia/SD-induced apoptosis was significantly attenuated by recombinant rat ANGPTL4 in a concentration dependent manner. Moreover, ANGPTL4 decreased the hypoxia/SD-induced caspase-3 cleavage and the cytochrome C release, but increased the Bcl-2/Bax ratio and the mitochondrial membrane potential. Decreased expression of integrin β1, the ANGPTL4 receptor was observed during hypoxia/SD conditions, however, such decrease was reversed by ANGPTL4. In addition, ANGPTL4 induced integrin β1-associated FAK and Src phosphorylation, which was blocked by anti-integrin β1 antibody. ANGPTL4 also reversed the hypoxia/SD-induced decrease of Akt and ERK 1/2 phosphorylation, and the effect of ANGPTL4 was abolished by inhibitors of either integrins, ERK1/2, or phosphatidylinositol 3-kinase (PI3K). Blocking integrinβ1, Akt or ERK largely attenuated anti-apoptotic effect of ANGPTL4. ANGPTL4 protects MSCs from hypoxia/SD-induced apoptosis by interacting with integrins to stimulate FAK complex, leading to downstream ERK1/2 and PI3K/Akt signaling pathways and mimicking the pathway in which MSCs contact with the extracellular matrix. 相似文献
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Zhang Yi Li Shuo Liang Ying Zhao Hailiang Hou Leiping Shi Yu Ahammed Golam Jalal 《Journal of Plant Growth Regulation》2019,38(1):357-357
Journal of Plant Growth Regulation - The original version of this article unfortunately contained errors in two authors' names. The given and family names of the authors were incorrectly... 相似文献
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Kai Wang Yuchen Hou Bed Poudel Dong Yang Yuanyuan Jiang Min‐Gyu Kang Ke Wang Congcong Wu Shashank Priya 《Liver Transplantation》2019,9(37)
Biomacromolecular pigments, such as melanin, play an essential role in the survival of all living beings. Melanin absorbs sunlight and transforms it into heat, which is crucial for avoiding damage to skin cells. Light absorption produces excited electrons, which could either fall back to ground states by releasing the heat (photothermal effect) and/or light (photoluminescence), or stay at higher energy levels within its lifetime period, which can be captured through external electronic circuitry (photovoltaic effect). In this study, it is demonstrated that the combination of melanin with halide perovskite light absorber in the form of a composite exhibits high absorbance from the UV to NIR region in the solar spectrum. And the composite displays significantly reduced photoluminescence and minimized density of residual excited states (verified by photovoltaic measurement) owing to the significantly enhanced nonradiant quenching by the melanin. As a result, the composite shows an ultrahigh solar‐thermal quantum yield of 99.56% and solar‐thermal conversion efficiency of ≈81% under one‐sun illumination (AM1.5), which is superior to typical carbon materials such as graphene (≈70%). By coating the photothermal composite film on the hot‐side of thermoelectric devices, a 7000% increase in output power as compared to the blank device under illumination is observed. 相似文献
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