Double Cherry Blossom Leaf Extract Effects Tumor Cell-Cycle and Induces Apoptosis
An interesting study by Shibato, Junko et al., “Towards identification of bioactive compounds in cold vacuum extracted double cherry blossom (Gosen-Sakura) leaves.”, has investigated the composition of Gosen-Sakura (Double Cherry Blossom) leaf extract and its effects on tumor cells.
Component analysis results of the Gosen-Sakura leaf extract
The study confirmed that the Gosen-Sakura extract contains the known anti-tumor compounds coumarin and benzyl alcohol. Further, it compared the anti-tumor effects of the Gosen-Sakura extract on HeLa cells with those of coumarin, benzyl alcohol, and coumarin combined with benzyl alcohol. Per the below figure, the results suggested that the Gosen-Sakura extract contains a novel third substance with anti-tumor activity.
Effect of Gosen-Sakura leaf extract on the cell cycle
The study then examined the effect of Gosen-Sakura leaf extract on the cell cycle in HeLa (immortal cervical cancer cell line) and A549 (adenocarcinomic human alveolar basal epithelial cell line) cells. Using the Biocolor Cell-Clock™ Cell Cycle Assay, cells were stained and the cell percentages in G1 stage, S phase, G2 and M phase were determined as below:
"Staining of the HeLa and A549 cells by the cell-clock cell cycle assay kit after treatment with the double cherry blossom leaf extract for 48 housing. The bar pattern represents the cells percentages in G1 stage: slant, S phase: filled, G2 and M phase: horizontal, respectively, and the number of cells per cell cycle was calculated as a ratio from the ratio of each color tone to the total pixel value."
After treatment with the Gosen-Sakura extract, the proportion of cells in G1 and S phases increased by stagnation in G1 and S phases. As G1 and S phases are the preparation period for DNA synthesis and the period of DNA replication, the results imply that inhibition of tumor cell proliferation by Gosen-Sakura extract is occurring during the DNA synthesis process.
Gosen-Sakura leaf extract induces apoptosis
HeLa and A549 cells were treated with H2O2 (hydrogen peroxide) as a positive control, with 0% Gosen-Sakura leaf extract (negative control), and with 3%, 5% and 7% Gosen-Sakura leaf extract. Using the Biocolor Cell-APOPercentage™ Apoptosis Assay, apoptotic cells were stained red, and the results confirmed increased in apoptosis incidence as the concentration of Gosen-Sakura extract increased.
The study verified the that the Gosen-Sakura extract contains two known compounds with anti-tumor activity and at least one additional novel bioactive compound. Further, it made important observations towards understanding the underlying mechanism of action for the anti-tumor effects that were demonstrated. The researchers concluded that their results warrant further study to isolate and identify the novel compound that was as yet unknown at the time of publication.
Shibato, Junko et al. “Towards identification of bioactive compounds in cold vacuum extracted double cherry blossom (Gosen-Sakura) leaves.” Plant signaling & behavior vol. 14,10 (2019): e1644594. doi:10.1080/15592324.2019.1644594
The Biocolor Cell-Clock™ Cell Cycle Assay is a live cell detection and measurement system that can be employed to monitor the four major phases of the mammalian cell cycle during in vitro culture. The assay uses a redox dye that is imported by cycling cells.
The Biocolor Cell-APOPercentage™ Apoptosis Assay is a detection and MEASUREMENT system which allows the user to monitor the incidence of apoptosis (programmed cell death) in mammalian, anchorage dependent cells during in vitro culture. The assay uses a dye that is selectively imported by cells undergoing apoptosis. Necrotic cells cannot retain the dye and therefore are not stained.