Inhibition of nitric oxide production in lipopolysaccharide-activated RAW264.7 macrophages by isolated xanthones from the roots of Cratoxylum formosum ssp. pruniflorum

Abstract

The inhibitory activity of extract and compounds isolated from the roots of Cratoxylum formosum ssp. pruniflorum against nitric oxide (NO) was evaluated using RAW264.7 cells. Isolation of the CH2Cl2 extract of C. formosum ssp. pruniflorum roots afforded ten known xanthones including six tri-oxygenated xanthones (1-6) and four tetra-oxygenated xanthones (7-10), respectively. Compound 7 showed the highest inhibitory activity against NO release with an IC50 value of 3.9 μM, followed by compound 8 with an IC50 value of 4.3 μM, respectively. In order to understand the mechanism of this anti-inflammatory activity, the transcriptional level of 7 was found to down regulate mRNA expressions of iNOS and COX-2 in dose-dependent manners, whereas 8 inhibited only iNOS mRNA expression but did not affect on that of COX-2 gene. Xanthones might be the main anti-inflammatory components in C. formosum ssp. pruniflorum.

Xanthones, A Promising Anti-Inflammatory Scaffold: Structure, Activity, and Drug Likeness Analysis

“…Among the xanthones isolated from the roots of Cratoxylum formosum ssp. pruniflorum, several compounds (6, 15-18, 21, 26-28, and 37) showed anti-inflammatory activity in LPS-induced RAW 264.7 macrophages [37]. Dulxisxanthone F (21) was found to downregulate the mRNA expression of iNOS and COX-2 in dose-dependent manners, and 5,9-dihydroxy-8-methoxy-2,2-dimethyl-7-(3-methylbut-2-enyl)-2H,6H-pyrano- [3,2b]-xanthone (27) only inhibited the mRNA expression of iNOS but not COX-2.…”

Chemical and Biological Research on Herbal Medicines Rich in Xanthones

“…During the past ten years, plants belonging to the Artocarpus [ 154 ], Calophyllum [ 185 ], Cratoxylum [ 41 ], and Garcinia [ 46 ] genera have been reported to display anti-inflammatory activity. Pyranocycloartobiloxanthone A ( 96 , Figure 9 ), a novel xanthone isolated from A. obtusus [ 154 ] presented not only anti-inflammatory and anti-oxidant activities, but also anti-apoptotic and anti-bacterial effects against Helicobacter pylori .…”

“…The inhibitory effects of 1,7-dihydroxy-8-methoxyxanthone ( 97 ), cochinchinone A ( 98 ), formoxanthone A ( 99 ), macruraxanthone ( 4 ), cochinxanthone E ( 100 ), pruniflorone L ( 101 ), dulcisxanthone F ( 102 ), 5,9-dihydroxy-8-methoxy-2,2-dimethyl-7-(3-methyl-but-2-enyl)-2 H ,6 H -pyrano-[3,2 b ]-xanthone ( 103 ), pruniflorone K ( 104 ), and garcinone B ( 105 ) ( Figure 9 ) obtained from C. formosum ssp. pruniflorum showed inhibitory effects on NO production by murine macrophage-like RAW264.7 cells [ 41 ]. Among them, compounds 99 , 102 , 103 displayed good suppressive ability on NO production with IC 50 values of 8.0, 3.9, and 4.3 μM, respectively, while 98 , 100 and 105 showed moderate activity with IC 50 values of 12.6, 12.8 and 11.8 μM, respectively.…”

Chemopreventive Effect of Cratoxylum formosum (Jack) ssp. pruniflorum on Initial Stage Hepatocarcinogenesis in Rats

“…Pruniflorone K/L, cochinchinone A/I, formoxanthone B, braxilixanthone, garcinone B, vieillardiixanthone B, and gerontoxanthone I were also found in CP roots [ 30 , 31 , 32 , 33 ], in addition to xanthene and anthraquinone derivatives [ 18 , 34 ]. Dulcisxanthone B from the root displayed anti-inflammation activity in a lipopolysaccharide-activated RAW264.7 cell line by inhibiting nitric oxide production [ 35 ], whereas cochinchinone C inhibits cancer phenotypes by downregulating NF-κB in multidrug-resistant A549 lung cancer cell line [ 36 ]. The green fruit of CP contains formoxanthone C, pruniflorone M-O, xanthonolignoid, and flavonoid derivative [ 37 , 38 , 39 ].…”