The present study investigated the material basis of Urtica fissa for the inhibition of benign prostatic hyperplasia(BPH). The active fractions were screened, and the extracts of dichloromethane and ethyl acetate exhibited significantly inhibitory activities against 5α-reductase in vitro and BPH in model rats. The chemical constituents in the active fractions were systematically investigated, and 28 compounds were obtained, which were identified as lobechine methyl ester(1), dibutyl-O-phthalate(2), 1-monolinolein(3), epipinoresinol(4), 5-hydroxy-3,4-dimethyl-5-pentanyl-2(5H)-furanone(5), E-7,9-diene-11-methenyl palmitic acid(6), evofolin B(7), ficusal(8), threo-2,3-bis-(4-hydroxy-3-methoxyphenyl)-3-ethoxypropan-1-ol(9), α-viniferin(10),(9R,7E)-9-hydroxy-5,7-mengatigmadien-4-one-9-O-β-D-glucopyranoside(11), indole-3-carboxaldehyde(12), p-hydroxy ethyl cinnamate(13), benzyl alcohol-O-β-D-glucoside(14), L-methionine(15), 4-methoxyaniline(16), 6-aminopurine(17), 8'-acetyl oilvil(18), 4-methoxyl-8'-acetyl oilvil(19), vanillic acid(20), β-hydroxypropiovanillone(21), 7-hydroxy-6-methoxycoumarin(22), p-hydroxybenzaldehyde(23), pinoresinol(24), erythro-1,2-bis-(4-hydroxy-3-methoxyphenyl)-1,3-propanediol(25), urticol(26), urticol-7-O-β-D-glucopyranoside(27), and lobechine(28). Compounds 1-17 were isolated from U. fissa for the first time. Meanwhile, compound 1 was a new natural product. Compounds 10, 11, 19, 21, and 27 exhibited significant inhibitory effects on 5α-reductase.
Keywords: 5α-reductase; Urtica fissa; active constituents; benign prostatic hyperplasia.