UPLC-ESI-QTOF-MS/MS and 1 H-NMR identification of alkaloids in potent fraction of Catharanthus roseus leaves inhibits migration and invasion of MDA-MB-231 cells

Catharanthus roseus is well-known for the discovery of some important pharmaceuticals used for the treatment of many diseases including tumors and cancer. The anti-migratory and anti-invasive properties of C. roseus leaves extract on MDA-MB-231 breast cancer cells were reported from previous project. Therefore, the present study was carried out to identify the metabolites of C. roseus leaves through bioassay-guided fractionation using UPLC-ESI-QTOF-MS/MS spectrometric and 1 H-NMR spectroscopic data analysis. The scratch assay showed that the bioactive fractions significantly inhibited the migration of MDA-MB-231 cells. The transwell migration and invasion assays showed that the most potent fraction significantly inhibited the migration and invasion of MDA-MB-231 cells in a concentration-dependent manner. The enzymatic study on the proteolytic activity of MMP-2 and MMP-9 enzymes using gelatin zymography and ELISA indicated that the inhibitory activity of the potent fraction on MDA-MB-231 cell migration and invasion is possibly through the inhibition of MMP-2 and MMP-9 enzymes. The HPLC-DAD, UPLC-ESI-QTOF-MS-MS and 1 H-NMR data identified vindoline as the most abundant alkaloid and vindorosine, vincristine and norseredamine (isomer) as the minor alkaloids in the most potent fraction. Docking study of vindoline, vindorosine and vincristine showed strong binding interactions to the active sites of MMP-2 and MMP-9 proteins. The results from the present study will lead to further anticancer studies of identified alkaloids individually or in combination, thereby supports the traditional uses of C. roseus leaves for cancer treatment.