Apoptosis-inducing Effect Of Polygonum Orientale L Extract On A549

Objective: To study proliferation-inhibitory and apoptosis-inducing effects ofPolygonum orientale L extract on human lung carcinoma cell line A549 in vitro andits mechanism.Methods: The proliferation inhibitory effect and cytotoxic activity of Polygonurnorientale L extract on A549 cell line were detected by MTT assay; morphological andultrastructural changes of apoptotic cells were investigated by inverted microscope,HE staining and transmission electron microscope (SEM); expression ofapoptosis-associated gene Bcl-2, Bax and P53 were determined byimmunohistochemical method (S-P method).Results: (1) MTT colorimetric assay revealed that the extract of Polygonum orientaleL had a significant inhibitory effect on A549 in vitro in a concentration andtime-dependent manner; (2) morphological changes: inverted microscope, HE stainingand TEM results indicated that the typical morphological and ultrastrucmral alterationof apoptosis were observed in Polygonum orientale L extract treated A549 cells, suchas cell body shrinkage, cytoplasm condensation, microvilli decrease or loss, chromatincondensing to the periphery of the nucleus forming crescents, nucleus disintegration,nuclear fragmentation and apoptotic body formation; (3) the expression ofapoptosis-associated gene bcl-2, bax and p53 had significantly changed as determinedby immunohistochemical method (P＜0.01).Conclusions: Polygonum orientale L extract has proliferation-inhibitory andapoptosis-inducing effect on hepatic carcinoma cell A549. Its apoptotic mechanismmay be mediated with the alteration of expression of apoptosis-associated gene bcl-2,bax and p53.