ABSTRACT
ObjectiveTo study the effect and underlying mechanism of Stemona tuberosa alkaloids on the proliferation and apoptosis of human non-small cell lung cancer NCI-H460 cells. MethodNon-small cell lung cancer NCI-H460 cells were divided into a blank group and S. tuberosa alkaloids groups （50， 100， 150， 200， and 250 mg·L-1）. The effect of S. tuberosa alkaloids on the proliferation of human NCI-H460 cells was observed by thiazolyl blue tetrazolium bromide （MTT） assay and colony formation assay. Cell apoptosis was observed by Hoechst 33258 staining and flow cytometry. Real-time fluorescence-based polymerase chain reaction （Real-time PCR） was used to detect the effect of S. tuberosa alkaloids on the mRNA expression of cysteinyl aspartate-specific protease 3 （Caspase-3）， B-cell lymphoma-2 （Bcl-2）， Bcl-2-associated X protein （Bax）， and epidermal growth factor receptor （EGFR）. The protein expression levels of Caspase-3， Bax， Bcl-2， protein kinase B （Akt）， phosphorylated （p-）Akt， EGFR， c-Jun N-terminal kinase （JNK）， p-JNK， p38 mitogen-activated protein kinase （p38 MAPK）， and p-p38 MAPK were measured by Western blot. ResultCompared with the blank group， the S. tuberosa alkaloids groups showed increased inhibition rate on cell proliferation （P<0.01）， reduced number of cell clones formed and the rate of cell clonal formation （P<0.05， P<0.01）， and increased karyopyknosis， cytoplasmic aggregation， and cell apoptosis rate （P<0.01）. The S. tuberosa alkaloids groups at 100， 150， 200， and 250 mg·L-1 showed increased Caspase-3 mRNA expression （P<0.05）， decreased EGFR mRNA expression （P<0.05， P<0.01）， up-regulated protein expression of Caspase-3 and p-JNK （P<0.01）， and down-regulated protein expression of EGFR and p-Akt （P<0.05， P<0.01）. Additionally， compared with the blank group， the S. tuberosa alkaloids groups showed increased expression of Bax mRNA （P<0.01）， decreased expression of Bcl-2 mRNA （P<0.01）， up-regulated protein expression of Bax and p-p38 MAPK （P<0.01）， and down-regulated protein expression of Bcl-2 （P<0.01）. ConclusionsS. tuberosa alkaloids can inhibit proliferation and induce apoptosis of human non-small cell lung cancer NCI-H460 cells， and the mechanism may be related to the inhibition of EGFR protein expression and phosphorylation of Akt protein， as well as the activation of the JNK/p38 MAPK signaling pathway.
ABSTRACT
ObjectiveTo investigate the effect of Stemona tuberosa alkaloids （STA） on apoptosis and phosphatidylinositol 3-kinase/protein kinase B （PI3K/Akt） and c-Jun N-terminal kinase/p38 mitogen-activated protein kinase （JNK/p38 MAPK） signaling pathways in human lung cancer A549 cells. MethodA549 cells were classified into blank group and STA groups （100， 150， 200， 250， 300 mg⋅L-1）. Thiazole blue （MTT） assay and colony formation assay were used to evaluate the proliferation of A549 cells. Apoptosis was observed based on Hoechst 33258 staining， flow cytometry， and Annexin V-FITC/PI staining. Western blot was employed to detect the expression of apoptosis-related proteins cysteine-aspartic acid protease-3 （Caspase-3）， B-cell lymphoma-2 （Bcl-2）-associated X protein （Bax）， and Bcl-2， and the expression of PI3K， phosphorylated （p）-PI3K， Akt， p-Akt， JNK， p-JNK， p38 MAPK， and p-p38 MAPK. ResultCompared with the blank group， STA groups （150， 200， 250， 300 mg⋅L-1） demonstrated the increase in inhibition rate of cell proliferation （P<0.01） and cell clone inhibition rate， and decrease in cell clone formation rate （P<0.01）. In comparison with the blank group， STA groups showed typical characteristics of apoptosis， such as chromatin condensation and enhanced fluorescence reaction. The apoptosis rate of STA groups was significantly higher than that of the blank group （P<0.01）. Compared with the blank group， STA （150， 200， 250， 300 mg⋅L-1） significantly up-regulated the protein expression of Caspase-3 and Bax （P<0.05， P<0.01） and down-regulated the expression of Bcl-2 protein （P<0.01）. Compared with the blank group， STA had no significant influence on the total protein expression of PI3K， Akt， JNK， and p38 MAPK. However， STA （150， 200， 250， 300 mg⋅L-1） significantly decreased the levels of p-PI3K and p-Akt （P<0.05， P<0.01） and increased the level of p-p38 MAPK （P<0.05， P<0.01）. Compared with the blank group， STA （200， 250， 300 mg⋅L-1） significantly raised the level of p-JNK （P<0.05， P<0.01）. ConclusionSTA can inhibit the proliferation and induce the apoptosis of A549 cells by inhibiting PI3K/Akt signaling pathway and activating JNK/p38 MAPK signaling pathway.
ABSTRACT
Objective To analyze the chemical constituents of kumquat essential oil(KEO)and the acute toxicity of KEO in mice. Methods The chemical constituents of KEO were analyzed by GC-MS. After preliminary test,KM mice were randomly divided into control and KEO groups with 20 mice in each group(10 male and 10 female). The doses of KEO were designed with ratio 0.758 be?tween the 100%and 0%mortality amount as 10,7.60,5.70,4.40,3.30 and 2.50 ml/kg. The acute toxicity was evaluated by examina?tion of the mice for 14 days after single administration of KEO. Results The principal constituents in KEO wereα-pinene(0.46%),β-phellandrene(0.11%),β-myrcene(2.34%),D-limonene(95.62%),geranyl acetate(0.10%),β-copaene(0.67%),andγ-elemene (0.13%),which accounted for 99.43%of the total chemical content of KEO. The half-lethal dose(LD50)of KEO in mice by the acute toxicity test was 6.24 ml/kg with the 95%confidence limit of(5.39-7.33)ml/kg in female mice and 5.73 ml/kg with the 95%confi?dence limit of(4.91-6.79)ml/kg in male mice. The possible toxic target organs were liver,spleen and gastrointestinal tract. Conclu?sion KEO with the content of D-limonene was obtained from kumquat for the first time,and the toxicity of the KEO was low accord?ing to the toxicity classification standard of World Health Organization.