Objective - （ ） To investigate the effects of nuclear factor erythroid 2 related factor 2 NRF2 on the oxidative stress （ ） Methods ） ，， induced by trichloromethane TCM in human normal hepatocyte L02 cells. i L02 cells were stimulated with 1 2 ， ， ， （ ）， 4 8 12 16 and 20 mmol/L TCM solution dissolved in dimethyl sulfoxide and the control group and blank group were set ， - ， up. After culturing for 24 hours the cell viability was detected by CCK 8 colorimetric method and the concentration of TCM ） -， - stimulation was screened. ii L02 cells in logarithmic growth phase were randomly divided into control group and low medium - ， ， ， and high dose groups. After 24 hours of exposure to 0 4 8 and 12 mmol/L TCM the cells were collected. The activity of （ ）， （ ）， （ - ） （ ） superoxide dismutase SOD catalase CAT glutathione peroxidase GSH Px and the level of malondialdehyde MDA NRF2， - （HO-1）， were detected by colorimetric analysis. The mRNA expression levels of heme oxygenase 1 glutamate cysteine （GCLC） （） （NQO1） - ligase catalytic subunit and NAD P H quinone dehydrogenase 1 were detected by real time fluorescence ， - ， polymerase chain reaction. The protein levels of NRF2 HO 1 GCLC and NQO1 were detected by Western blotting.Results ） ， ， ， ， i When the concentration of TCM was 4 8 12 16 and 20 mmol/L the survival rate of L02 cells decreased （ P ） ， ， significantly compared with the control group all <0.05 . The concentration of 0 4 8 and 12 mmol/L were selected as the ） ， - stimulation doses for subsequent experiments. ii Compared with the control group the activities of SOD and GSH Px in L02 （ P ） （ P ）， - cells in the three doses groups decreased all <0.05 and the levels of MAD increased all <0.05 with a dose effect - （P ）， relationship. The CAT activity of L02 cells in the medium dose group was lower than that in the control group <0.05 and the - （ P ） CAT activity of L02 cells in the high dose group was lower than that in the others three groups all <0.05 . Compared with the ， NRF2 - （P ），NRF2 control group the relative expression levels of mRNA in L02 cells in the low dose group decreased <0.05 - （P ）， NRF2 mRNA in L02 cells in the medium dose group increased <0.05 mRNA and NRF2 protein expression in L02 cells in （ P ） HO-1，GCLC， NQO1 ， the highdose group increased both <0.05 . The relative expression level of mRNA and GCLC NQO1 （ P ） protein expression in L02 cells in the three doses groups increased compared with the control group all <0.05 . The relative NRF2 - - - expression level of mRNA in L02 cells in the high dose group was higher than that in the low and medium dose groups （ P ）， - （P ）， both <0.05 and the relative expression of NRF2 protein was higher than that in the low dose group <0.05 but the HO-1 GCLC - - （ relative expression levels of and mRNA and HO 1 protein level were lower than those in the medium dose group all P ）Conclusion - <0.05 . TCM exposure can inhibit the proliferation of L02 cells by inducing oxidative stress with a dose effect ， relationship. In this process the antioxidant mechanism mediated by NRF2 was activated. The expression of antioxidant defense ， - ， and detoxification related target genes downstream of NRF2 signaling pathway was activated and the expression of HO 1 - GCLC and NQO1 was up regulated to alleviate the oxidative damage caused by TCM.

OBJECTIVETo determine the plasma protein binding rate of arctiin and arctigenin.

METHODThe ultrafiltration combined with HPLC was employed to determine the plasma protein binding rate of arctiin and arctigenin as well as rat plasma and healthy human plasma proteins.

RESULTThe plasma protein binding rate of arctiin with rat plasma at the concentrations of 64. 29, 32.14, 16.07 mg x L(-1) were (71.2 +/- 2.0)%, (73.4 +/- 0.61)%, (78.2 +/- 1.9)%, respectively; while the plasma protein binding rate of arctiin with healthy human plasma at the above concentrations were (64.8 +/- 3.1)%, (64.5 +/- 2.5)%, (77.5 +/- 1.7)%, respectively. The plasma protein binding rate of arctigenin with rat plasma at the concentrations of 77.42, 38.71, 19.36 mg x L(-1) were (96.7 +/- 0.41)%, (96.8 +/- 1.6)%, (97.3 +/- 0.46)%, respectively; while the plasma protein binding rate of arctigenin with normal human plasma at the above concentrations were (94.7 +/- 3.1)%, (96.8 +/- 1.6)%, (97.9 +/- 1.3)%, respectively.

CONCLUSIONThe binding rate of arctiin with rat plasma protein was moderate, which is slightly higher than the binding rate of arctiin with healthy human plasma protein. The plasma protein binding rates of arctigenin with both rat plasma and healthy human plasma are very high.

Animals ; Binding, Competitive ; Blood Proteins ; metabolism ; Chromatography, High Pressure Liquid ; Furans ; metabolism ; Glucosides ; metabolism ; Humans ; Lignans ; metabolism ; Male ; Protein Binding ; Rats ; Rats, Sprague-Dawley ; Ultrafiltration ; methods