Evaluation of Budesonide–hydroxypropyl-β-cyclodextrin inclusion complex in thermoreversible gels for ulcerative colitis

Abstract

Background New formulations for topical treatment of ulcerative colitis with budesonide inclusion complex (BUDHP-β-CD) and poloxamers (PL) were developed for future clinical use. Aims This study evaluated the efcacy of such novel formulations in a rat model of colitis. Methods The PL-BUDHP-β-CD systems were prepared by direct dispersion of the complex (BUD concentration 0.5 mg mL−1) in solutions with PL407 or PL403. Male Wistar rats underwent TNBS-induced colitis and were treated for 5 days by a rectal route, as follows: BUD 1: BUDHP-β-CD +PL407 (18%); BUD 2: BUDHP-β-CD +PL407 (20%); BUD 3: BUDHP-β-CD +PL407 (18%)+PL403 (2%); BUD 4: plain BUD; BUD 5: BUDHP-β-CD; C1: HP-β-CD+PL407 (18%); C2: HP-β-CD+PL407 (20%); C3: HP-β-CD+PL407 (18%)+PL403 (2%); C4: saline. A negative control group without colitis was also used. Colitis was assessed via myeloperoxidase (MPO) activity, and macroscopic and microscopic damage score in colon tissues. Protein levels of TNF-α, IL-1β, IL-10 and endogenous glucocorticoids were obtained using ELISA. Results BUDHP-β-CD poloxamer formulations had similar MPO activity when compared with the negative control group. All formulations presented lower MPO activity than BUDHP-β-CD and plain BUD (p<0.001). BUD 2 produced lower microscopic score values than plain BUD and BUDHP-β-CD (p<0.01). All formulations with BUDHP-β-CD poloxamers reduced TNF-α levels (p<0.05). Conclusion Novel budesonide inclusion complex formulations improved microscopic damage and reduced colonic MPO activity and TNF-α levels