New lanostanes and naphthoquinones isolated from Antrodia salmonea and their anti-oxidative burst activity in human leukocytes

Four new compounds were isolated from the basidiomata of the fungus Antrodia salmonea, a newly identified species of Antrodia (Aphyllophorales) in Taiwan. These new compounds are named as lanosta-8,24-dien-3,15,21-triol (1), 24-methylene-lanosta-8-en-3,15,21-triol (2), 2,3-dimethoxy-5-(2’,5’-dimethoxy- 3’,4’-methylenedioxy-phenyl)-7-methyl-[1,4]-naphthoquinone (3), and 2,3-dimethoxy-6-(2’,5’-dimethoxy-3’,4’-methylenedioxy-phenyl)-7-methyl-[1,4]-naphthoquinone (4), respectively. Their structures were elucidated by spectroscopic methods. An in vitro cellular functional assay was performed to evaluate their anti-oxidative burst activity in human leukocytes. They showed inhibitory effect against phorbol-12-myristate-13-acetate (PMA), a direct protein kinase C activator, -induced oxidative burst in neutrophils (PMN) and mononuclear cells (MNC) with 50% inhibitory concentration (IC50) ranging from 3.5 to 25.8 µM. The potency order of these compounds in PMA-activated leukocytes was as 1>3>4>2. They were relatively less effective in formyl-Met-Leu-Phe (fMLP), a G-protein coupled receptor agonist, -induced oxidative burst, except for compounds 3 and 4 in fMLP-activated PMN. These results indicated that three (1, 3 and 4) of these four newly identified compounds displayed anti-oxidative effect in human leukocytes with different potency and might confer anti-inflammatory activity to these drugs.