Study on inhibition of Dendrobium officinale extract on gastric carcinogenesis / 中草药

ABSTRACT

Objective: To explore the inhibitory effects of Dendrobium officinale extract (DOE) on gastric carcinogenesis and its related molecular mechanism. Methods: The rats were randomly divided into normal group, model group, positive drug group, low-dose and high-dose DOE groups. The gastric carcinogenesis model was induced by ig giving 200 mg/kg N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) at doses of 200 mg/kg every 10 days for 3 months. Meanwhile, the rats in the treatment groups were given the corresponding doses of drug while the rats in the control group were given normal saline. At the end of the experiment, the degree of gastric tissue carcinogenesis was calculated by HE staining analysis. The expression levels of EGF, EGFR, Bax, and Bcl-2 mRNA were detected by RT-PCR test in gastric tissue. The levels of EGF and EGFR in plasma were detected by ELISA. Apoptosis was detected by TUNEL assay. Results: Compared with the model group, the high-dose DOE could inhibit the degree of carcinogenesis significantly (P < 0.01). Both high-dose and low-dose DOE could significantly reduce the levels of EGF, EGFR mRNA, and Bcl-2 mRNA, and increase the levels of Bax mRNA in gastric tissue, with statistical significance compared with the model group (P < 0.05, 0.01). In addition, they also reduced the levels of EGF and EGFR in plasma significantly and induced apoptosis. Conclusion: DOE could inhibit the gastric carcinogenesis, which might be related to effects of decreasing the expression of EGF and EGFR mRNA in gastric tissue and EGF and EGFR in plasma and inducing the apoptosis through reducing the expression of Bcl-2 mRNA and increasing Bax mRNA.