Inhibitory And Apoptosis-inducing Effects Of The Serum Of Rabbit Taking Orally Cobra Venom On Hepatocarcinoma

AIM To investigate the inhibitory and apoptosis-inducing effect of the serum of rabbit taking orally cobra venom (SRCV) on hepatocarcinoma.METHOD We used the human HepG-2 cells and human fetal lung fibroblast as target cells and established the animal model of mice transplanted hepatoma. The inhibitory effect was observed by means of trypan blue dye exclusion test in vitro and inhibitory rate test in vivo. The toxicity of SRCV was studied by using the acute toxicity and EDso test. In addition, the flow cytometry (FCM), transmission electron microscopy (TEM) and the method of TUNEL were applied to observe the apoptosis-inducing effect of SRCV in vivo.RESULT 1) The cytotoxicity action of SRCV was markedly stronger than that of the normal rabbit serum at the same dosage, and SRCV 5 mg/ml showed striking opposing-proliferation action on HepG-2 cells. Meanwhile, SRCV also displayed some auxo-action on proliferation of human fetal lung fibroblast. 2) The results of LDso and EDso tests showed that the toxicity of SRCV was the lowest among three cobra venom (CV) preparations. Comparing the inhibitory rate (IR) of three CV preparations in a dose of the 1/3 of their LDi, we found that IR of SRCV was the highest and IR of the other CV preparation which was denatured by the acid and heat was no more than that of the CV. 3) By FCM and TUNEL assay, we found that the apoptosis rate of tumor tissue was significantly increased by the SRCV. Under the TEM, the apoptosis cells could be observed. And we could, also see the apoptosis cells on the TUNEL slice.CONCLUSION 1) SRCV selectively inhibits the growth of HepG-2 cells but has no cytotoxicity on human fetal lung fibroblast. And this action is related to its suppressing proliferation of tumor cells. 2) After the CV is denatured or digested, its anticancer activity is still remained. And the toxicity of SRCV is lower than that of the others, but the tumor inhibitory effect more remarkable. 3) SRCV can induce apoptosis of tumor cells in vivo, which is identical with the results of apoptosis-inducing effect research in vitro, and hints that the tumor inhibitory effect of SRCV is related to its apoptosis-inducing effect. 4) The toxicity of SRCV is still remained to the extent, so it is necessary that SRCV would be separated and purified to reduce its toxicity.