Caffeic acid phenethyl ester is a potent inhibitor of HIF prolyl hydroxylase: structural analysis and pharmacological implication.

Caffeic acid phenethyl ester (CAPE) is an active component of propolis from honeybee. We investigated a potential molecular mechanism underlying a CAPE-mediated protective effect against ischemia/reperfusion (I/R) injury and analyzed the structure contributing to the CAPE effect. CAPE induced hypoxia-inducible factor-1 (HIF-1) alpha protein, concomitantly transactivating the HIF-1 target genes vascular endothelial growth factor and heme oxygenase-1, which play a protective role in I/R injury.

N,N'-Bis(5-aminosalicyl)-L-cystine is a potential colon-specific 5-aminosalicylic acid prodrug with dual therapeutic effects in experimental colitis.

To evaluate N,N'-bis(5-aminosalicyl)-L-cystine (5-ASA-Cys) as a potential colon-specific 5-aminosalicylic acid prodrug with dual therapeutic effects in experimental colitis, the pharmacokinetics and therapeutic activity were investigated after oral administration of 5-ASA-Cys and amelioration of experimental colitis was compared after rectal administration of 5-aminosalicylic acid (5-ASA) and/or cysteine. In addition, the gluthathione (GSH) level in the inflamed colonic tissue was examined after administration of cysteine or 5-ASA-Cys. Oral administration of 5-ASA-Cys delivered much greater amount of 5-ASA to the large intestine and excreted lower amount of 5-ASA via urine than that of free 5-ASA.

Synthesis and properties of N,N'-bis(5-aminosalicyl)-L-cystine as a colon-specific deliverer of 5-aminosalicylic acid and cystine.

N,N(')-bis(5-aminosalicyl)-L-cystine (5-ASA-Cys) was prepared by a simple synthetic route. 5-ASA-Cys was not degraded in pH 1.2 and 6.

Quercetin activates an angiogenic pathway, hypoxia inducible factor (HIF)-1-vascular endothelial growth factor, by inhibiting HIF-prolyl hydroxylase: a structural analysis of quercetin for inhibiting HIF-prolyl hydroxylase.

We investigated a molecular mechanism underlying quercetin-mediated amelioration of colonic mucosal injury and analyzed chemical structure contributing to the quercetin's effect. Quercetin up-regulated vascular endothelial growth factor (VEGF), an ulcer healing factor, not only in colon epithelial cell lines but also in the inflamed colonic tissue. VEGF derived from quercetin-treated colon epithelial cells promoted tube formation.

A molecular mechanism for the anti-inflammatory effect of taurine-conjugated 5-aminosalicylic acid in inflamed colon.

In previous reports, a novel colon-specific prodrug, 5-aminosalicyltaurine (5-ASA-Tau) administered orally, is successfully delivered to and liberates 5-aminosalicylic acid (5-ASA) and taurine in the inflamed large intestine of rats. Furthermore, the prodrug ameliorates the 2,4,6-trinitrobenzene-sulfonic acid-induced colitis, and taurine acts not only as a carrier but also as an active therapeutic agent. In this study, we investigated the anti-inflammatory properties of the prodrug at a molecular level.