Efficient In Vitro and In Vivo Anti‐Inflammatory Activity of a Diamine‐PEGylated Oleanolic Acid Derivative

Abstract

Recent evidence has shown that inflammation can contribute to all tumorigenic states. We have investigated the anti‐inflammatory effects of a diamine‐PEGylated derivative of oleanolic acid (OADP), in vitro and in vivo with inflammation models. In addition, we have determined the sub‐cytotoxic concentrations for anti‐inflammatory assays of OADP in RAW 264.7 cells. The in‐ flammatory process began with incubation with lipopolysaccharide (LPS). Nitric oxide production levels were also determined, exceeding 75% inhibition of NO for a concentration of 1 μg/mL of OADP. Cell‐cycle analysis showed a reversal of the arrest in the G0/G1 phase in LPS‐stimulated RAW 264.7 cells. Furthermore, through Western blot analysis, we have determined the probable molecular mechanism activated by OADP; the inhibition of the expression of cytokines such as TNF‐α, IL‐1β, iNOS, and COX‐2; and the blocking of p‐IκBα production in LPS‐stimulated RAW 264.7 cells. Finally, we have analyzed the anti‐inflammatory action of OADP in a mouse acute ear edema, in male BL/6J mice treated with OADP and tetradecanoyl phorbol acetate (TPA). Treatment with OADP induced greater suppression of edema and decreased the ear thickness 14% more than diclofenac. The development of new derivatives such as OADP with powerful anti‐inflammatory effects could represent an effective therapeutic strategy against inflammation and tumorigenic processes.