Inhibitive Effects Of The Solasonine Extracted From Solanum Nigrum On Lung Cancer Cells

Solanum nigrum is a fairly common plant with a high nutritional content. It is ofrelatively high medicinal value and is usually used as a traditional medicine againsttumor. Solanum nigrum is also used as food. It is an edible plant as well as amedicinal one. All parts of the plant can be used as drugs. Its bioactive componentsmainly include steroid alkaloid, polysaccharide, vitamin A, vitamin C and so on,among which, steroid alkaloid demonstrates antineoplastic activity. Solanum nigrumis therefore listed as one of top10anti-tumor herbs. With the advantages of beingwidely found, easy processing, inexpensiveness and convenience, solanum nigrum isa natural drug with good prospects for medicinal application.Human lung adenocarcinoma A549cells and mouse Lewis lung carcinomas cellshave been widely used in cell models of lung cancer to conduct the in vitropulmonary toxicological study and the antitumous effect study, which has become akey field in the anticancer research.The MTT method was applied to detect the inhibitive effects of the solasoninefrom solanum nigrum on A549and LLC cells. Cell morphological observation wascarried out after the two types of lung cancer cells have been treated by solasoninewith a dose slightly higher than the median lethal dose. The flow cytometry inAnnexin V/PI double staining and the fluorescence quantitative PCR analysis wereconducted after A549cells have been treated by solasonine with a dose slightlyhigher than the median lethal dose. In the end, the MTT method was adopted tocompare the effect of solasonine and the aglycone (solasodine) after its hydrolysis oninhibiting the same two types of lung cancer cell in the same experimentalconditions.The research finding shows that the solasonine can significantly inhibits bothA549and LLC cell growth; and the inhibitive effect is basically proportional to theconcentration of solasonine. Their IC50after24hours’ treatment were about18μg/mL and20μg/mL respectively; most of A549cells treated by20μg/mLsolasonine show a shrinking dying form, and the flow cytometry in Annexin V/PI double staining show the total cell death rate after24hours is42.43%((Q2+Q3)/(Q2+Q3+Q4)), among which the ratio of early apoptosis cells wasabout22.08%(Q3/(Q2+Q3)), the ratio of late apoptosis or late apoptosis andnecrosis cells was about77.92%(Q2/(Q2+Q3)); the SYBR green fluorescencequantitative PCR analysis data show that solasonine significantly enhanced theexpression level of Puma gene；The solasodine can significantly inhibits both A549and LLC cell growth, and the inhibitive effect is basically proportional to theconcentration of solasodine; and both of their IC50values after24hours’ treatmentare about7.5μg/mL.The results show that the solasonine from solanum nigrum evidently inhibits thegrowth of lung cancer cells, mainly by inducing cell apoptosis or cell apoptosis andnecrosis; and it is closely connected with the greatly enhanced expression level ofPuma in the p53pathway; The change of the structure in which the hydrolysis ofsolasonine causes the release of aglycone improves efficiency of inhibiting tumorcells, which demonstrates that the aglycone is the effective component of solasodineand solasonine which inhibits the growth of tumor cells.