Jun‑Ming Chen,Jue Zhang,Yong‑Mei Xia,Xiao‑Xia Wang,Jian Li
Steviol is the colonic metabolite of the natural sweetener steviol glycosides. It does not diffuse to the blood and the half maximal inhibitory concentration of steviol is longer compared with that of current chemotherapy agents, including 5‑fluorouracil and doxorubicin. The present study demonstrated that steviol inhibits the proliferation of the human osteosarcoma U2OS cell line in a dose‑ and time‑dependent manner, and that the inhibition rate is comparative with that of doxorubicin and 5‑fluorouracil. The mechanism of this anticancer activity is also investigated. The results indicated that steviol inhibits U2OS cells through inducing G1 phase cell cycle arrest, downregulating the ability of colony formation via a mitochondrial apoptotic pathway, which was indicated by an increase of the Bax/Bcl‑2 ratio and activation of cyclin‑dependent kinase inhibitor 1, tumor protein 53 and cyclin‑dependent kinase; whereas a Survivin and Caspase 3‑independent mechanism was involved. Considering that steviol appears minimally in the plasma during metabolism, and possesses a median lethal dose of 100-fold greater compared with that of 5‑fluorouracil, it may become a potential chemotherapy agent.
The diterpenoid isosteviol is one of the stevia derivatives that have reported various activities . In mice inhaling isosteviol, OVA- and ACh-induced bronchial asthma showed a dose-dependent improvement of a decline in the expression of inflammatory cytokines and the infiltration of basophils. Compared with inhalation of budesonide 0.6 mg/kg, sensitized mice inhaling 1.0 mg/kg dosage of isosteviol performed a higher tolerate against the ACh stimulation. In behavior tests, the 1.0 mg/kg isosteviol nebulization reached almost 80% of the level of budesonide with regard to the ameliorative effects on depression-like behavior and improvement in sport ability. In addition, lung and systemic inflammation were markedly prevented by isosteviol with a dosage of more than 0.6 mg/kg, which exhibited limited expression of IL-1β and TNF-α, less infiltration of basophils in lung tissues, and a low level of systemic immunocytes, which showed in hematoxylin and eosin staining, RT-PCR, and ELISA results. On the other hand, none of the abnormal pathology was found in both peripheral and central organs of all the administration groups. Generally, this study implicated that the mechanism could involve effects of isosteviol inhalation on the suppression of IL-1β and TNF-α to restrict a systemic upsurge of immunocytes and infiltration into the lung that prevents the occurrence of depression-like behavior and hypokinesia.
危险品化学品经营许可证（带存储）