Oxidized 5-aminosalicylic acid activates Nrf2-HO-1 pathway by covalently binding to Keap1: Implication in anti-inflammatory actions of 5-aminosalicylic acid.

Mesalazine (5-aminosalicylic acid, 5-ASA), a currently used drug for anti-inflammatory bowel disease, is easily oxidized by HOCl, a strong oxidant generated in gut inflammation, to produce electrophilic quinones. We investigated whether this chemical feature has an implication in the anti-inflammatory pharmacology of 5-ASA. Human colon carcinoma HCT116 cells were treated with HOCl-reacted 5-ASA.

Colon-targeted cell-permeable NFκB inhibitory peptide is orally active against experimental colitis.

For the purpose of development of orally active peptide therapeutics targeting NFκB for treatment of inflammatory bowel disease (IBD), two major barriers in oral delivery of therapeutic peptides, metabolic lability and tissue impermeability, were circumvented by introduction of a colon-targeted delivery system and cell permeable peptides (CPP) to NFκB inhibitory peptides (NIP). Suppression of NFκB activation was compared following treatment with various CPP conjugated NIPs (CPP-NIP). The most potent CPP-NIP was loaded in a capsule coated with a colon specific polymer, which was administered orally to colitic rats.

N-succinylaspart-1-yl celecoxib is a potential colon-specific prodrug of celecoxib with improved therapeutic properties.

To develop a colon-specific prodrug of celecoxib, a cyclooxygenase-2 selective inhibitor, which could improve cardiovascular toxicity and therapeutic effectiveness for chemoprevention of colorectal cancer, aspart-1-yl celecoxib (A1C) or aspart-4-yl celecoxib (A4C), succinyl celecoxib (SC), and N-succinylaspart-1-yl celecoxib (SA1C) or N-succinylaspart-4-yl celecoxib (SA4C) were prepared and evaluated as a prodrug with such beneficial properties. On incubation with the small intestinal contents while SC, SA1C, and SA4C were stable, A1C and A4C were degraded to liberate celecoxib. In the cecal contents, the other conjugates except for SC and SA4C were cleaved to release celecoxib.

Structure-activity relationship of salicylic acid derivatives on inhibition of TNF-α dependent NFκB activity: Implication on anti-inflammatory effect of N-(5-chlorosalicyloyl)phenethylamine against experimental colitis.

To develop a more potent NFκB inhibitor from salicylic acid which is known to inhibit activity of NFκB, a transcription factor regulating genes involved in immunity, inflammation and tumorigenesis, derivatives of salicylic acid (SA) where the 5 position, carboxyl or hydroxyl group was modified were treated in HCT116 cells transfected with an NFκB dependent luciferase gene and LPS-stimulated RAW264.7 cells. Amidation of the carboxylic group or substitution of chlorine at the 5 position increased the ability of SA to suppress the expression of NFκB dependent luciferase and inducible nitric oxide synthase, a product of an NFκB target gene.