Cytotoxic Activities of Total Saponins from Plena Clematis on Human Tumor Cell Lines In Vitro / 中国结合医学杂志

OBJECTIVE@#To investigate the anti-proliferative effects of saponins prepared from Plena Clematis (PC) cultured in Fujian Province, China on 4 human tumor cell lines and its possible anti-tumor mechanism.@*METHODS@#The growth inhibition assays of saponins on human esophageal squamous carcinoma cell line (EC9706), human hepatoma cell line (HepG-2), human oral cancer cell line (KB) and human gastric cancer cell line (BGC-823) were evaluated in vitro by thiazolyl blue (MTT) method. The inhibitory effects on EC9706 treated with different concentrations of saponins (15.62, 31.25, 62.50, 125, 250 and 500 μg/mL) were performed in vitro by MTT method. The morphology and nuclear staining with acridine orange/ethidium bromide of EC9706 cells treated with saponins were illustrated under an inverted phase fluorescence microscope. The apoptotic effects of saponins were further evaluated by annexin-V/propidium iodide dual staining experiment to examine the occurrence of phosphatidylserine externalization onto the cell surface by a flflow cytometer.@*RESULTS@#MTT assay showed that the saponins could inhibit the proliferation of 4 tumor cell lines. Among them, the maximum inhibition rate of 73.1% was detected in EC9706 cells at the saponins concentration of 250 μg/mL for 24 h. Further investigation indicated that the saponins induced EC9706 cells apoposis. The EC9706 cells presented apoptotic characteristics when treated with saponins, including that the morphologies of EC9706 cells were appeared round-shaped with higher refraction, and the cell nuclear stained orange with EB after 250 μg/mL saponins exposure. The flow cytometry analysis results showed that the induction of cell cycle arrest in apoptotic system may participate in the anti-proliferative activity of saponins on EC9706 cells.@*CONCLUSION@#The saponins from PC exhibited significant cytotoxicity against human EC9706, KB, BGC-823, and HepG-2 cells and might be beneficial to development of ethnic pharmaceutical plant for potential anti-tumor drugs.

Subchronic Oral Toxicity of Silica Nanoparticles and Silica Microparticles in Rats / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the subchronic oral toxicity of silica nanoparticles (NPs) and silica microparticles (MPs) in rats and to compare the difference in toxicity between two particle sizes.</p><p><b>METHODS</b>Sprague-Dawley rats were randomly divided into seven groups: the control group; the silica NPs low-, middle-, and high-dose groups; and the silica MPs low-, middle-, and high-dose groups [166.7, 500, and 1,500 mg/(kg•bw•day)]. All rats were gavaged daily for 90 days, and deionized water was administered to the control group. Clinical observations were made daily, and body weights and food consumption were determined weekly. Blood samples were collected on day 91 for measurement of hematology and clinical biochemistry. Animals were euthanized for necropsy, and selected organs were weighed and fixed for histological examination. The tissue distribution of silicon in the blood, liver, kidneys, and testis were determined.</p><p><b>RESULTS</b>There were no toxicologically significant changes in mortality, clinical signs, body weight, food consumption, necropsy findings, and organ weights. Differences between the silica groups and the control group in some hematological and clinical biochemical values and histopathological findings were not considered treatment related. The tissue distribution of silicon was comparable across all groups.</p><p><b>CONCLUSION</b>Our study demonstrated that neither silica NPs nor silica MPs induced toxicological effects after subchronic oral exposure in rats.</p>