(-)-Menthol

(-)-Menthol is a key component of peppermint oil that binds and activates transient receptor potential melastatin 8 (TRPM8), a Ca²⁺-permeable nonselective cation channel, to increase [Ca²⁺]_i^[1]. Antitumor activity^[1]. IC50 & Target: TRPM8^[1] In Vitro: (-)-Menthol (Menthol ) per se does not exhibit antiproliferative activity, but it is able to enhance 1α,25(OH)₂D₃-mediated growth inhibition in LNCaP cells. At high (-)-Menthol concentrations above 1.6 mM, the cells begin to detach from the culture dish^[1].
(-)-Menthol (0.8 mM) can increase [Ca²⁺]i via transmembrane influx or store release pathways. Peak increase in [Ca²⁺]_i was 102.3±39 nM (n=3) in (-)-Menthol alone and 124.5±51 nM (n=3) in combination of 1α,25(OH)₂D₃ with (-)-Menthol, respectively^[1].
Combination of 1α,25(OH)₂D₃ with (-)-Menthol (0.8 mM) cooperatively modulates bcl-2 and p21 expression^[1].