Biological Effects of Salvia Officinalis Leaf Extract on Murine Myeloma Cells

Background: In the Mediterranean region, Salvia officinalis plant is widely used and routinely added to food for a traditional culinary utilization, and moreover, from long time, it is recognized to possess pharmacological activities. Objectives: In the present study, we investigated the biological properties of S. officinalis leaf ethanol extracts and a thin layer chromatography‑isolated spot on murine myeloma cells. Materials and Methods: 3‑(4,5‑dimethylthiazol‑2‑yl)‑2, 5‑diphenyltetrazolium bromide tests were carried out to determinate the EC50 of both the leaf extracts and the isolated spot; the isolated spot was also investigated by liquid chromatography–mass spectrometry (LC‑MS) and nuclear magnetic resonance (NMR). Electron microscopy and immunofluorescence were used for morphological studies on treated P3X murine myeloma cells. Results: LC‑MS and NMR techniques identified methyl carnosate, a methyl derivative of carnosic acid, as the main component of spot B. Moreover, scanning electron microscopy, transmission electron microscopy, and immunofluorescence investigations carried out on murine myeloma cells treated for 20 h with EC50 values of spot B revealed some changes both in the cellular morphology and in the microtubular array. Conclusions: The present studies indicate that S. officinalis extracts have biological effects on murine myeloma cells and identify methyl carnosate as an interesting molecule for further investigations on human cell lines and possibly on cancer prevention.