The anti-rheumatoid arthritis property of the folk medicine Dianbaizhu (Gaultheria leucocarpa var. yunnanensis, Ericaceae).

The Chinese folk medicine Dianbaizhu, consisting of Gaultheria species, is widely used for the treatment of rheumatoid arthritis by several minority nationalities. The species and plant parts of this genus used as Dianbaizhu in clinical application are confused. In order to elucidate the species and the medicinal parts, as well as to ascertain the effective components and the probable optimal source of Dianbaizhu, the different plant parts and polarity fractions of its mainstream species, G. leucocarpa var. yunnanensis were investigated. The inhibition of nitric oxide and tumor necrosis factor produced in macrophage J774 were used to assess the anti-inflammatory effect of those samples. G. leucocarpa var. yunnanensis may be the preferred species for anti-RA effect. The underground parts of this taxon showed the best anti-inflammatory and anti-RA activities; the n-butanol and water fractions of the underground parts may be the most anti-RA active.