OBJECTIVE：The relative content of trichosanthin (TCS) of the calli induced from the leaves of Trichosanthes kirilowii Maxim. was measured and a comparison between the calli and the root was made. METHODS：TCS was obtained by the fractional precipitate with acetone from the homogenate of the root or the calli. To examine and measure TCS, several methods, such as immuno-precipitation reaction, SDS-PAGE and electrophoregram scanning, were usde. RESULTS：The results of immuno-precipitation reaction and SDS-PAGE showde that TCS existed in the calli and in the root of T.kirilowii Maxim.. It was found that TCS was the richest component in the acetone precipitated crude extract of the calli with a relative content of 44.22% TCS in the extract, though the absolute content of TCS in the calli was less than that in the root. CONCLUSION:Extracting TCS from the calli derived from leaves has not been reported previously. The absolute content of TCS in the root is 2.66 times more than that in the calli.

Objective To investigate the effect of pyrroloquinoline quinone(PQQ) on the aging of rat hippocampal neurons induced by D-galactose(D-gal).Methods Hippocampal neurons were cultured in vitro.The aging of the hippocampal neurons was induced by high dose D-gal,PQQ protection were used 30 min before D-gal.The metamorphosis of hippocampal neurons was observed under the microscope.The contents of free radical was measured.The incidence of apoptosis of hippocampus cells was tested with the flow cytometry.The expression of Bax was detected with immunohistochemical staining.Results After the cells cultured in vitro exposed to D-gal,the content of free radical and the expression of Bax of the hippocampal neurons increased.After pretreatment of the cultured neurons with PQQ,the contents of free radical and the expression of Bax decreased,the survival of hippocampal neurons increased.Conclusion PQQ may slow the aging progress of hippocamal neurons induced by D-gal.

Objective To investigate the effects of gambogic acid on proliferation,invasion and protein expression of MMP-2 in LoVo human colon cancer cell line.Methods The CCK-8 assay was used to determine the anti-proliferation ability.Transwell chamber assay was used to study the invasion of LoVo colon cancer cells.Western Blot was applied to examine the protein expression of MMP-2.Results CCK-8 assay showed that after cells treated with 1,2,4 μmol/L GA for 24 h,48 h the inhibition rates were(0.16±0.11)％,(0.24±0.08)％,(0.58±0.01)％,(0.67±0.03)％,(0.79±0.01)％ and (0.27±0.05)％,(0.69±0.09)％,(0.85±0.01)％,(0.87±0.01)％,(0.89±0.01)％,and there had statistically significant differences between control group (0 μmo/L) with experimental group (P＜0.05).Gambogic acid can effectively inhibit LoVo cells invasion at a low-dose concentration,which the numbers of cells that digested the matrigel in control group (0 μmo/L)was 120.50± 8.69 and 69.83 ±4.75 in experimental group (1 μnol/L),P＜ 0.05).Western Blot revealed that Gambogic acid can down-regulate the expression of MMP-2,which the levels of down-regulating the expression of MMP-2 after treated with 1,2,4 umol/L GA were 48.67％,74.72％and 82.70％ (P＜0.05) Conclusion Gambogic acid can effectively inhibit the growth and invasion of the LoVo cells,which may be related with down-regulating the expression of MMP-2.

IF1 (ATPIF1) is a nuclear DNA-encoded mitochondrial protein whose activity is inhibition of the F