interleukin-8 and pregna-4-17-diene-3-16-dione

Bile acids have recently been associated with the pathogenesis of irritable bowel syndrome (IBS). We therefore evaluated the expression of bile acid receptors in the intestinal mucosa of IBS patients as well as the effects of bile acids on small intestinal epithelial cells.. Intestinal biopsy specimens were obtained from 15 IBS patients and 15 healthy controls. The effects of bile acid stimulation on trans-epithelial electrical resistance (TEER) and permeability in differentiated Caco-2 cells were measured. Proinflammatory cytokines were measured by enzyme-linked immunosorbent assay. mRNA levels of bile acid receptors, including farnesoid X receptor (FXR), and cytokines were determined by real-time reverse transcription-PCR. Caco-2 cells were pre-incubated with the FXR antagonist guggulsterone.. FXR mRNA expression at the terminal ileum was increased in IBS patients. Chenodeoxycholic acid (CDCA) significantly decreased TEER, increased permeability, and increased interleukin-8 (IL-8) release from Caco-2 cells. Pre-incubation with guggulsterone blocked CDCA-mediated IL-8 release; however, the decrease in TEER was not reversed. CDCA-induced IL-6 and IL-8 mRNA levels were blocked by guggulsterone. CDCA increased IL-6, tumor necrosis factor-α (TNF-α), and vascular endothelial growth factor release, whereas guggulsterone significantly blocked IL-6 and TNF-α release.. FXR expression was elevated at the terminal ileum in IBS patients. CDCA increased proinflammatory cytokines, while guggulsterone blocked these increases.

Topics: Adult; Aged; Biopsy; Caco-2 Cells; Case-Control Studies; Chenodeoxycholic Acid; Enterocytes; Female; Healthy Volunteers; Humans; Ileum; Interleukin-6; Interleukin-8; Irritable Bowel Syndrome; Male; Middle Aged; Permeability; Pregnenediones; Receptors, Cytoplasmic and Nuclear; RNA, Messenger; Tumor Necrosis Factor-alpha

We already showed that the plant sterol guggulsterone has been reported to inhibit nuclear factor-kappaB (NF-kappaB) 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-kappaB signals and the upregulated expression of interleukin-8 (IL-8) in COLO 205 cells stimulated with tumor necrosis factor-alpha (TNF-alpha). Pretreatment with GG-50B and GG-52 attenuated the increased IkappaB kinase (IKK) and IkappaBalpha phsophorylation induced by TNF-alpha. 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-kappaB 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.

Topics: Animals; Anti-Inflammatory Agents; Cell Line, Tumor; Chemokine CCL2; Colitis; Dextran Sulfate; Epithelial Cells; Humans; I-kappa B Kinase; Interleukin-8; Intestinal Mucosa; Mice; Mice, Inbred C57BL; NF-kappa B; Prednisolone; Pregnenediones; Pregnenes; Sulfasalazine; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha