Novel guggulsterone derivative GG-52 inhibits NF-κB signaling in intestinal epithelial cells and attenuates acute murine colitis

Abstract

We already showed that the plant sterol guggulsterone has been reported to inhibit nuclear factor-κB (NF-κB) signaling in intestinal epithelial cells (IECs) and to attenuate dextran sulfate sodium (DSS)-induced colitis. This study investigates the anti-inflammatory effects of novel guggulsterone derivatives on IEC and preventive and therapeutic murine models of DSS-induced colitis. Novel guggulsterone derivates with high lipophilicity were designed and four derivates, including GG-46, GG-50B, GG-52, and GG-53, were synthesized. Two guggulsterone derivatives, GG-50B and GG-52, significantly inhibited the activated NF-κB signals and the upregulated expression of interleukin-8 (IL-8) in COLO 205 cells stimulated with tumor necrosis factor-α (TNF-α). Pretreatment with GG-50B and GG-52 attenuated the increased I κB kinase (IKK) and I κBα phsophorylation induced by TNF-α. In preventive and therapeutic models of murine colitis, administration of GG-52 significantly reduced the severity of DSS-induced colitis, as assessed by disease activity index, colon length, and histology. In contrast, GG-50B did not show a significant reduction in the colitis severity. Moreover, the efficacy on attenuating colitis by GG-52 was comparable to that by sulfasalazine or prednisolone. These results indicate that the novel guggulsterone derivative GG-52 blocks NF-κB activation in IEC and ameliorates DSS-induced acute murine colitis, which suggests that GG-52 is a potential therapeutic agent for the treatment of inflammatory bowel diseases. Laboratory Investigation (2010) 90, 1004-1015; doi: 10.1038/labinvest.2010.54; published online 1 March 2010