Inhibitory Effects of Xanthones from Guttiferae Plants on PAF-Induced Hypotension in Mice

Abstract

The inhibitory effects of 22 xanthones from three Guttiferae plants (Hypericum patulum, Calophyllum inophyllum and C. austroindium) on exogenous platelet activating factor (PAF)-induced hypotension were examined using a blood pressure monitoring in vivo assay method. Guanandin (2), caloxanthone E (3), 1,3,5,6-tetrahydroxy-2-isoprenylxanthone (8), 6-deoxyjacareubin (11) and patulone (18) showed strong inhibition of PAF-induced hypotension, with inhibitory effects of more than 60 %. Their ID50 values were greater than that of ginkgolide B (BN-52 021), a natural PAF-antagonist from the Ginkgo biloba.

Review on mechanisms and interactions in concomitant use of herbs and warfarin therapy

“…Many members of this group contain compounds that have already been identified, such as lignans and sesquiterpenes from burdock, xanthones from hidcote [23], flavonoids from garcinia [24], and the widely reported ginkgolide B from ginkgo [25].…”

The Genus Calophyllum: Review of Ethnomedicinal Uses, Phytochemistry and Pharmacology

“…Xanthones isolated form C. inophyllum exhibited in vivo anti-inflammatory activity when administered through intraperitoneal or oral routes in rats (Gopalakrishnan et al 1980). Oku et al (2005) studied inhibitory effects of 22 xanthones on exogenous plateletactivating factor (PAF)-induced hypotension in in vivo assay. The result of the study showed that caloxanthone E, 1,3,5,6-tetrahydroxy-2-isoprenylxanthone, 6-deoxyjacareubin and guanidine showed 60% inhibition in PAF-induced hypotension (Oku et al 2005).…”

Prenylated xanthones from Hypericum ascyron

“…Various constituents of H. ascyron have been reported to date, and flavonoids [3][4][5][6] and xanthones [7] have been confirmed as components of this plant. The family Clusiaceae is a known rich source of xanthones [8,9], which have been shown to have various bioactivities, including those of anti-methicillin-resistant Staphylococcus aureus (MRSA) [10][11][12], anti-vancomycin-resistant Enterococci (VRE) [13], anti-malarial [14], tumor-promoting inhibition [15], selective cyclooxygenase-2 inhibition [16], and inhibitory effects on platelet-activating factor (PA-F)-induced hypotension [17]. In the course of our search for bioactive natural products from plants, we became interested in Hypericum plants and their chemical constituents.…”