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Objective To investigate the effects of Loropetalum chinense extracts on the proliferation of lung adenocarcinoma A549 cells cultured in vitro. Methods CCK-8 assay was performed to evaluate the effect of Loropetalum chinense extracts on the proliferation of A549 cells, and the clonal growth ability of A549 cells was determined by clone formation assay. Flow cytometry Annexin V-APC/PI double staining was used to measure the apoptosis of A549 cells. Western blot was used to measure the expressions of apoptosis-related proteins Bax, Fas, Bcl-2 Caspase3 and cleaved-Caspase 3. Results Loropetalum chinense extracts significantly inhibited the proliferation and colony formation of A549 cells in a time- and dose-dependent manner. The viability of A549 cells decreased by 50% after 48h treatment of 0.5mg/ml extracts, and 100% inhibition of colony formation rate achieved when the cells were treated with 40μg/ml extracts for 14 days. When A549 cells were treated with Loropetalum chinense extracts for 24h, apoptotic rates increased in a dose-dependent manner. Compared with the control group, the protein levels of Fas, Bax, Caspase3 and cleaved-Caspase3 were up-regulated, while Bcl-2 was down-regulated. Conclusion Loropetalum chinense extracts inhibit the growth of human lung adenocarcinoma cells in vitro, and the mechanisms may be related to the activation of mitochondrial and death receptor apoptosis pathway.
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Objective To investigate the protective effects of isopimaric acid ( ISO), the BKCa channel activator, on cognitive function and synaptic plasticity in APP/PS1 mice. Methods Alzet osmotic pump was loaded with ISO or DMSO only and assembled with ALZET Brain Infusion Kit III. The cannula was implanted into the lateral ventricle of 4-month-old male APP/PS1 mice or matched wild type ( WT) mice. Two weeks later, open field test and Morris water maze were conducted. Paired-pulse facilitation ( PPF) and TBS-induced long-term potentiation ( LTP ) were recorded in CA1 region of hippocampus. Results The open field test showed that there was no significant difference among the four groups in spontaneous activities and vertical plane movement distance within 30 minutes. Floor plane movement distance was significantly greater in APP/PS1+DMSO group than that in WT+DMSO group(P<0.05) . Compared with the WT+DMSO group, APP/PS1+DMSO group had significantly longer escape latency from the third to fifth day and lower percentage of time spent in the target quadrant ((43.27±3.24)% vs (34.19±2.56)%) and the number of crossing through the platform ((4.25±0.66)times vs (1.93±0.33)times)(P<0.05). Compared with the APP/PS1+DMSO group, the APP/PS1+ISO group had significantly shorter escape latency from the fourth to fifth day and higher percentage of time spent in the target quadrant ((46.16±3.51)%) and the number of crossing through the platform ((3.41±0.34) times) (P<0.05). PPF in APP/PS1+DMSO group significantly reduced compared with that in WT+DMSO group at 30-50ms interstimulus interval(P<0.05). PPF in APP/PS1+ISO group((224.50±13.79)%) was significantly augment compared with APP/PS1+DMSO ((174.99 ±6.68)%) group at 40 ms interstimulus interval (P<0.05). The LTP at 60 min post-TBS was significantly smaller in the APP/PS1+DMSO group ((135.19±1.32)%) than that in the WT+DMSO group ((172.17± 4.15)%)(P<0.001). The LTP of the APP/PS1+ISO group((160.48±1.19)%) became significantly in-creased compared with that in the APP/PS1+DMSO group(P<0.001).Conclusion BKCa channel activator ISO improve the learning and memory function of APP/PS1 mice by promoting PPF and increasing LTP to recover synaptic plasticity in the hippocampus.
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Objective To investigate the dose-response relationship of the treatment temperatures and heating time on human cervical carcinoma hela cells,aiming at providing experimental evidences for clinical hy-perthermia. Methods Hela cells were heated at 37 ～ 70 ℃ in temperature-controlled water baths, the tempera-ture was divided into nine groups,each time was divided into eight subgroups (1 ～ 30 min). The morphology changes of cells after hyperthermia were detected by inverted microscope. Proliferation rates were measured by MTT colorimetric assay. The apoptesis rates were determined by flow eytometric analyse. The levels of prolifera-ring cell nuclear antigen (PCNA) were measured with immunohistochemistry. Results lnereaseing the heating time at the same temperature, or increaseing heating temperature at the same time, the cell proliferation, survival rates and PCNA expression decreased. There was no significant morphological change about cells ,but have small amount of apoptosis and a direct role of the suppression and destruction at 41 ℃ and 43 ℃ group. A large num-ber of cells shrinked to round and a major role for apoptosis at 46℃ group. Cell necrosis was major role at 50 ℃and 55 ℃ group. More than 55 ℃ for necrotic cells. Conclusion With the increase of heating temperature and heating time, its treatment of Hela cells gradually enhance. So combining dose-effect relationship of hyperthermia temperature and time can reach the best therapeutic effects.
ABSTRACT
As a quantitative evaluation approach for tumor hyperthermia,thermal dosimetry is a critieat part of the treatment planning system and plays a key role in governing the relationships between thermal exposure(temperature and time of exposure)and thermal damage.Its principal theories,parameters as well as thermal dosimetry models are potentially to accurately describe the tumor hyperthermia effectiveness and therefore greatly improve the clinical experience and prescription for tumor hyperthermia.The deep study and wide clinical application of thermal dosimetry in hyperthermia will further standardize tumor hyperthermia and benefit the patients more.