Structure-activity relationship for antiinflammatory effect of luteolin and its derived glycosides

Abstract

Luteolin and its derived glycosides such as a cynaroside, cesioside, isoorientin and stereolensin have been isolated and identified from different kinds of plant species. A (13)C NMR spectroscopic analysis of stereolensin has been done for the first time. These structurally related flavonoids were examined in vitro for their abilities to inhibit enzymes for the synthesis of thromboxane B(2) and leukotriene B(4) as well as hydrogen peroxide scavenging activity. Luteolin exhibited a high inhibitory activity against both thromboxane and leukotriene synthesis. In particular, a remarkable inhibitory effect was observed against leukotriene enzyme activity. The glycosides, cynaroside and cesioside, possessed a moderate inhibition activity against both enzyme synthesis pathways, while isoorientin and stereolensin exhibited selectively good activity against thromboxane synthesis. All the flavonoids showed excellent scavenging activity for the hydrogen peroxide at all the concentrations tested. The results demonstrated that the reactivities of luteolin and its related glycosides against arachidonic acid synthesis and hydrogen peroxide scavenging are dependent on their molecular structures. The presence of ortho-dihydroxy groups at the B ring and OH substitution pattern at C-5 position of the A ring could significantly contribute to the antiinflammatory and antioxidant activities of flavonoids.

Inhibition of 5-Lipoxygenase Product Synthesis by Natural Compounds of Plant Origin

“…Regarding the C-3-OH in ring B, luteolin 19 (lacking this moiety) is even more potent than its direct counterpart quercetin 11, a flavon-3-ol derivative [108]. Of interest, the prenylated flavonoids including payriflavonol 20, morusin 21, artonin E 22, sanggenon D 26, sophoraflavanone G 30 and kenusanone A 31 are highly efficient direct 5-LO inhibitors with IC 50 values 0.09 to 7 mM in cellfree assays [105].…”

Preliminary study on the anti-inflammatory and antioxidant activities of the leave extract of Hyptis fruticosa Salzm. ex Benth., Lamiaceae

“…Flavonoids are the major secondary metabolites class with several descriptions of antioxidant property which confers a therapeutic potential with anti-inflammatory effect (Rajendran et al, 2000;Li et al, 2002;Matsuda et al, 2003). Flavonoids have been shown to inhibit the inducible isoforms of cyclo-oxygenase (COX-2) and nitric oxide synthase (iNOS), lipooxygenase, microsomal monooxygenase, glutathione S-transferase, and nicotinamide adenine dinucleotide phosphate (NADPH)-oxidase, all involved in reactive oxygen species generation (Odontuya et al, 2005;Soobrattee et al, 2005). Others anti-inflammatory properties of flavonoids are their suggested ability to inhibit neutrophil degranulation and reduce complement activation, thereby decreasing the adhesion of inflammatory cells to the endothelium (Nijveldt et al, 2001).…”

Chemical composition and anti-arthritic activity of Anacyclus valentinus extract on adjuvant-induced arthritis in rats

“…Quercetin, myricetin, kaempferol and apigenin identified in the extract have an effect on the synthesis of cyclooxygenase and lipoxygenase [36,37]. Luteolin 3-O-β-glucopyranoside also identified has an inhibitory effect on the synthesis of thromboxanes and consequently on the synthesis of the main arachidonic acid actor of the proinflammatory process [38].…”