ABSTRACT
Oridonin, which is isolated from Chinese herb Rabdosia rubescens (Hemsl.) Hara, has been implicated in regulation of tumor cell migration and invasion. In this study, treatment with oridonin enhanced the phosphorylation of myosin regulatory light chain (T18/S19) that regulates the ATPase activity of myosin IIA. Meanwhile, stress fibers were significantly more prominent after oridonin incubation, which impaired cell migration in transwell migration assays. All of these effects may be caused by the decreased interaction between myosin IIA and myosin phosphatase complex, but not kinases. Our data provide clear evidence of this novel pharmacological function for oridonin in treating cancer cell migration.
ABSTRACT
Complexations between three oridonin derivatives and ß-cyclodextrin (ßCD) were studied by nuclear magnetic resonance (NMR) method. Job's plots for complexes were depicted by (1)H NMR spectra chemical shifts, which proved the 1:1 stoichiometry inclusion complex formation between each derivative and ßCD. Two-dimensional rotating frame overhauser effect spectroscopy (2D ROESY) support the above conclusion and also proved that ring A of each oridonin derivative deeply enters into hydrophobic cavity from the wider rim and the other parts are outside the cavity. Apparent formation constants (Ka) of complexes between three oridonin derivatives and two CDs are calculated according to Scott's equation.
