Inhibition of mouse embryonic stem cell proliferation and induction of differentiation by natural products isolated from Rhazya stricta Decne.

Embryonic stem cells provide an ideal system to study various therapies for serious human diseases such as juvenile diabetes, neurodegenerative diseases, heart diseases and cancer. Synthetic or natural compounds that affect cell proliferation and/or differentiation of embryonic stem cells are of great value. Focus of the current project was upon the isolation and evaluation of natural components from a medicinal plant; Rhazya stricta on proliferation/ differentiation potential of embryonic stem cells. For this purpose, after a series of fractionation and purification steps, 7 compounds named as RS1-RS7 were isolated from aerial parts of the plant. The effects of these compounds were evaluated on the morphology and rate of cell proliferation of mouse naive embryonic stem cells. Only RS7 inhibited the proliferation of cell and reduced the induction of differentiation of cell. The qPCR analysis confirmed that the expression of the selected pluripotency markers (Oct4, Nanog and Sox2) was down regulated by RS7 treatment as compared to control. Furthermore, upon withdraw of Leukemia inhibitory factor (lif) from medium; effect of RS7 to promote differentiation was enhanced. Through structure elucidation studies, RS7 was found to be ursolic acid. This study first time shows the effect of natural compounds of Rhazya stricta Decne. on mouse embryonic stem cells.