Torilin is an inhibitor of testosterone 5 alpha-reductase, it (IC50 = 31.7 +/- 4.23 microM) shows a stronger inhibition of 5 alpha-reductase than alpha-linolenic acid (IC50 = 160.3 +/- 24.62 microM) but is weaker than finasteride (IC50 = 0.38 +/- 0.06 microM). Torilin has immunomodulatory, hepatoprotective, and anti-inflammatory properties, it inhibits inflammation by limiting TAK1-mediated MAP kinase and NF-κB activation, it can attenuate arthritis severity, modify leukocyte activations in dLNs or joints, and restore serum and splenocyte cytokine imbalances. Torilin inhibits melanin production in alpha-melanocyte stimulating hormone-activated B16 melanoma cells, with an IC(50) value of 25 microM. Torilin shows excellent antimicrobial activity against Bacillus subtilis ATCC 6633 spores and vegetative cells. Torilin has a potent anti-angiogenic activity both in vivo and in vitro, and it may have a strong activity to suppress tumorigenesis by inhibition of tumor invasion, it reverses multidrug-resistance in cancer cells, it can potentiate the cytotoxicities of adriamycin, vinblastine, taxol and colchicine against multidrug-resistant KB-V1 and MCF7/ADR cells.

Epidermal melanocytes synthesize melanin pigments and transfer them to keratinocytes, which is responsible for skin pigmentation. However, abnormal accumulation of melanin pigments causes hyperpigmentation disorders, which are substantially improved with treatment of tyrosinase inhibitor. In our ongoing study, Torilis japonica DC. (Umbelliferae) was found to inhibit melanin production. A goal of this study is to elucidate the hypopigmenting principle of T. japonica. METHODS AND RESULTS:A sesquiterpene structure of Torilin was isolated from the plant extracts via bioassay-guided phytochemical analysis. Torilin dose-dependently inhibited melanin production, with an IC(50) value of 25 microM, in alpha-melanocyte stimulating hormone (alpha-MSH)-activated B16 melanoma cells. Arbutin, a positive control of skin whitener, also inhibited alpha-MSH-induced melanin production with an IC(50) value of 170 microM. As to the mode of action, Torilin downregulated alpha-MSH-induced protein levels of tyrosinase without directly inhibiting catalytic activity of the enzyme. CONCLUSIONS: Taken together, this study shows that Torilin contributes to the hypopigmenting principle of T. japonica, and suggests its pharmacological potential in melanin-associated hyperpigmentation disorders[1].