Damage effect of Polygonum multiflorum fractions on human normal liver cells L02 and liver cancer cells HepG2 / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the damage effect of different fractions from Polygonum multiflorum on normal human liver and liver cancer cells, in order to seek for fractions that can obviously kill cancer cells but have less impact on normal liver cells, and make a preliminary study on different mechanism of the two kinds of cells.</p><p><b>METHOD</b>P. multiflorum water-eluted fraction (RW), 50% ethanol-eluted fraction (R50) and 95% ethanol-eluted fraction (R95) were successively obtained from 70% ethanol extracts of P. multiflorum, after being eluted by water, 50% ethanol and 95% ethanol and then absorbed by AB-8 macroporous resin. Normal human liver L02 cells and liver cancer HepG2 cells were incubated with cell supernatants from different fractions and cells. MTT method and inverted microscope were adopted to observe the impact of L02 on growth of HepG2 cells, screening fractions with damage effect and detect their doses and time effect. Giemsa stain showed changes in cell nucleus after administration and flow cytometry analysis was used to detect cycle and apoptosis of L02 cells.</p><p><b>RESULT</b>MTT method and inverted microscope showed that R50 had significant growth inhibition effects on L02 and HepG2 cells. According to giemsa stain and flow cytometry analysis, R50 showed different effect on inducing the two cells: there are much more apoptotic HepG2 cells than apoptotic L02 cells in each time phase (the proportion of the apoptosis cells in HepG2 group were 83.62%, 60.52% and 74.49%, and ID2 31.02%, 20.57% and 25.32% after treated with R50 for 24, 48, 72 h. Both cells showed less than 5% of apoptotic cells in the negative control group in each time phase). However, there is no significant impact on cycle of both cells.</p><p><b>CONCLUSION</b>R50 from P. multiflorum extracts had different damage effects on human liver L02 cells and liver cancer HepG2 cells, which was caused by different degree of induction on apoptosis of the two cells in nature.</p>

Effects of extract of Polygonum multiflorum on cell cycle arrest and apoptosis of human liver cell line L02 / 中西医结合学报

Objective: To analyze the chemical constituents of Polygonum multiflorum extract which may cause human liver cell damage and to explore the mechanism. Methods: Raw and processed Polygonum multiflorum were extracted by 70% ethanol, then raw and processed Polygonum multiflorum water-eluted material (RW and PW), 50% ethanol-eluted material (R50 and P50) and 95% ethanol-eluted material (R95 and P95) were obtained by absorbing through AB-8 macroporous resin, followed by water, 50% ethanol and 95% ethanol elution in order. The water extracts of raw and processed Polygonum multiflorum (RWE or PWE) were obtained by boiling them in water as usual. Normal human liver L02 cells were treated by different concentrations of eluted Polygonum multiflorum materials for different time, and the cell growth inhibition of each group was determined by methylthiazolyldiphenyl-tetrazolium bromide method. The chemical constituents which had a significant cytotoxicity to L02 cells were analyzed by high-performance liquid chromatography (HPLC). Morphological changes of L02 cells were observed by Giemsa staining and cell cycle distribution was observed by flow cytometry. Results: It was found that 95% ethanol-eluted extracts of raw and processed Polygonum multiflorum showed significant growth inhibition on normal human liver L02 cells, while the other components showed no significant inhibition on cell growth. HPLC analysis showed that the main component in 95% ethanol-eluted extract of raw and processed Polygonum multiflorum was emodin at content of (18.53+/-2.96)% and (10.28+/-1.34)% respectively. Cell cycle analysis showed that 95% ethanol-eluted material of Polygonum multiflorum and emodin had a similar significant effect of S phase arrest and all could induce L02 cell apoptosis. Conclusion: The main part of Polygonum multiflorum causing liver cell damage is the 95% ethanol-eluted extract, and emodin is one of the important chemical constituents leading to liver cell damage.