Cyclooxygenase-2 inhibitory cerebrosides from phytolaccae radix

A mixture of cerebrosides, called poke-weed cerebrosides, was purified from Phytolaccae Radix (Phytolaccaceae) and characterized as 1-O-beta-D-glucopyranosides of phytosphingosine type ceramides comprised of a common long chain base (2S,3S,4R,8Z)-2-amino-8-octadecene-1,3,4-triol and fatty acids. The fatty acyl chain of ceramide moieties was determined as (2R)-2-hydroxypentacosanoic acid, (2R)-2-hydroxylignoceric acid, (2R)-2-hydroxytricosanoic acid, (2R)-2-hydroxybehenic acid, (2R)-2-hydroxypalmitic acid, and palmitic acid. The pokeweed cerebroside inhibited the cyclooxygenase-2 dependent phase of prostaglandin D2 generation in bone marrow-derived mast cells in a concentration dependent manner with an IC50 of 6.2 microg/ml.