Cancer: Leukemia, colorectal., oral., esophageal
Action: Apoptosis,inhibits cell proliferation and migration
Gypenosides (Gyp), found in Gynostemma pentaphyllum Makino [(Thunb) Makino], have been used as folk medicine for centuries and have exhibited diverse pharmacological effects, including anti-leukemia effects in vitro and in vivo.
Gyp have been used to examine effects on cell viability, cell-cycle, and induction of apoptosis in vitro. They were administered in the diet to mice injected with WEHI-3 cells in vivo. Gyp inhibited the growth of WEHI-3 cells. These effects were associated with the induction of G0/G1 arrest, morphological changes, DNA fragmentation, and increased sub-G1 phase. Gyp promoted the production of reactive oxygen species, increased Ca2+ levels, and induced the depolarization of the mitochondrial membrane potential.
The effects of Gyp were dose- and time-dependent. Moreover, Gyp increased levels of the pro-apoptotic protein Bax, reduced levels of the anti-apoptotic proteins Bcl-2, and stimulated release of cytochrome c, AIF (apoptosis-inducing factor), and Endo G (endonuclease G) from mitochondria. The levels of GADD153, GRP78, ATF6-α, and ATF4-α were increased by Gyp, resulting in ER (endoplasmic reticular) stress in WEHI-3 cells. Oral consumption of Gyp increased the survival rate of mice injected with WEHI-3 cells used as a mouse model of leukemia.
Results of these experiments provide new information on understanding mechanisms of Gyp-induced effects on cell-cycle arrest and apoptosis in vitro and in an in vivo animal model (Hsu et al., 2011).
Inhibits Cell Proliferation and Migration
Results indicated that Gypenosides (Gyp) inhibited cell proliferation and migration in SW620 and Eca-109 cells in dose- and time-dependent manner. Gyp elevated intracellular ROS level, decreased the Δψ m, and induced apoptotic morphology such as cell shrinkage and chromatin condensation, suggesting oxidative stress and mitochondria-dependent cell apoptosis that might be involved in Gyp-induced cell viability loss in SW620 and Eca-109 cells. The findings indicate Gyp may have valuable application in clinical colon cancer and esophageal cancer treatments (Yan et al., 2013).
Gyp-induced cell death occurs through caspase-dependent and caspase-independent apoptotic signaling pathways, and the compound reduced tumor size in a xenograft nu/nu mouse model of oral cancer.
Gyp induced morphological changes, decreased the percentage of viable cells, caused G0/G1 phase arrest, and triggered apoptotic cell death in SAS cells. Cell-cycle arrest induced by Gyp was associated with apoptosis. The production of ROS, increased intracellular Ca(2+) levels, and the depolarization of ΔΨ(m) were observed. Gyp increased levels of the pro-apoptotic protein Bax but inhibited the levels of the anti-apoptotic proteins Bcl-2 and Bcl-xl. Gyp also stimulated the release of cytochrome c and Endo G. Translocation of GADD153 to the nucleus was stimulated by Gyp. Gyp in vivo attenuated the size and volume of solid tumors in a murine xenograft model of oral cancer (Lu et al., 2012).
Cell-cycle Arrest
Lin et al. (2011) have shown that gypenosides (Gyp) induced cell-cycle arrest and apoptosis in many human cancer cell lines. In the present study the effects of Gyp on cell morphological changes and viability, cell-cycle arrest and induction of apoptosis in vitro and effects on Gyp in an in vivo murine xenograft model were demonstrated. Results indicated that Gyp induced morphological changes, decreased cell viability, induced G0/G1 arrest, DNA fragmentation and apoptosis (sub-G1 phase) in HL-60 cells. Gyp increased reactive oxygen species production and Ca(2+) levels but reduced mitochondrial membrane potential in a dose- and time-dependent manner.
Oral consumption of Gyp reduced tumor size of HL-60 cell xenograft mode mice in vivo. These results provide new information on understanding mechanisms by which Gyp induces cell-cycle arrest and apoptosis in vitro and in vivo (Lin et al., 2011).
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