Cytotoxicity and Apoptosis Induced by Chenopodium ambrosioides L. Essential Oil in Human Normal Liver Cell Line L02 via the Endogenous Mitochondrial Pathway Rather Than the Endoplasmic Reticulum Stress.

Chenopodium ambrosioides L. (C. ambrosioides) has been used as dietary condiments and as traditional medicine in South America. The oil of Chenopodium ambrosioides L. (C. ambrosioides) can be used as a natural antioxidant in food processing. It also has analgesic, sedating, and deworming effects, and can be used along with the whole plant for its medical effects: decongestion, as an insecticide, and to offer menstruation pain relief. This study was conducted to investigate the cytotoxicity and apoptosis effects of an essential oil from C. ambrosioides in vitro. The cytotoxicity evaluation of the essential oil from C. ambrosioides on human normal liver cell line L02 was assessed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay. AO/EB dual fluorescent staining assay and Annexin V-FITC were used for apoptosis analysis. The changes in mitochondrial membrane potential (MMP) were analyzed with 5,5,6,6'-tetrachloro-1,1,3,3,-tetraethyl-imidacarbocyanine iodide (JC-1) dye under a fluorescence microscope. The level of apoptosis related protein expression was quantified by Western blot. The L02 cells were treated with the essential oil from C. ambrosioides at 24, 48, and 72 h, and the IC50 values were 65.45, 58.03, and 35.47 µg/mL, respectively. The AO/EB staining showed that viable apoptotic cells, non-viable apoptotic cells, and non-viable non-apoptotic cells appeared among the L02 cells under the fluorescence microscope. Cell cycle arrest at the S phase and cell apoptosis increased through flow cytometry in the L02 cells treated with the essential oil. MMP decreased in a concentration-dependent manner, as seen through JC-1 staining under the fluorescence microscope. In the L02 cells as shown by Western blot and qPCR, the amount of the apoptosis-related proteins and the mRNA expression levels of cytochrome C, Bax, Caspase-9, and Caspase-3 increased, Bcl-2 decreased, and Caspase-12, which is expressed in the endoplasmic reticulum, showed no obvious changes in protein amount or mRNA expression level. The essential oil form C. ambrosioides had a cytotoxic effect on L02 cells. It could inhibit L02 cell proliferation, arrest the cell cycle at the S phase, and induce L02 cell apoptosis through the endogenous mitochondrial pathway.

[Essential Oil of Chenopodium ambrosioides Induced Caspase-Dependent Apoptosis in SMMC-7721 Cells].

Objective: To investigate the inhibition of cell proliferation by essential oil of Chenopodium ambrosioides on the human liver cancer SMMC-7721 cells and human liver LO2 cells,and to study the mechanism of anti-tumor in vitro. Methods: The inhibition of cell proliferation by essential oil of Chenopodium ambrosioides was determined by MTT assay; the distribution of cell cycle was analyzed by flow cytometry( FCM) with PI staining; cell morphology and apoptosis effect of SMMC-7721 cells were observed by microscope; the apoptotic rate was quantified by FCM with Annexin V / PI double staining. Results: Essential oil of Chenopodium ambrosioides could significantly inhibit the cell proliferation in a concentration-time-dependent manner( P < 0. 05),and the IC50 values on SMMC-7721 cells were lower than human liver LO2 cells at 24,48 and 72 h,respectively( P < 0. 05); cell cycle of SMMC-7721 cells was arrested in G0/G1phase; morphological observation revealed that the cells were wrinkled and the cellular cohesiveness of cells was reduced; nuclear was condensed and in orange colour,of which were the late apoptotic features; and the apoptotic rate increased in a concentration-dependent manner( P < 0. 05),non-viable apoptotic rate was obviously decreased with caspase inhibitor in 100 µg / m L essential oil of Chenopodium ambrosioides( P < 0. 01). Conclusion: Essential oil of Chenopodium ambrosioides can inhibit SMMC-7721 cell proliferation, which may be related to inducing cell cycle arrest and caspase-dependent apoptosis.