Purpose: The effective treatment of ulcerative colitis (UC) poses substantial challenges, and the aetiopathogenesis of UC is closely related to infectious, immunological and environmental factors. Currently, there is a considerable need for the development of orally bioavailable dosage forms that enable the effective delivery of therapeutic drugs to local diseased lesions in the gastrointestinal tract.
Methods: Berberine (BBR) and Atractylodes macrocephala  Koidz (AM) volatile oil, derived from the Chinese herbs Coptis chinensis  Franch and Atractylodes macrocephala  Koidz, have anti-inflammatory and immunomodulatory activities. In this study, we prepared colon-targeted pellets loaded with BBR and stomach-targeted pellets loaded with AM volatile oil for the synergistic treatment of UC. The Box–Behnken design and β-cyclodextrin inclusion technique were used to optimize the enteric coating formula and prepare volatile oil inclusion compounds.
Results: The two types of pellets were spherical and had satisfactory physical properties. The pharmacokinetic results showed that the AUC and MRT values of the dual-targeted (DPs) pellets were higher than those of the control pellets. In addition, in vivo animal imaging confirmed that the DPs could effectively deliver BBR to the colon. Moreover, compared with sulfasalazine and monotherapy, DPs exerted a more significant anti-inflammatory effect by inhibiting the expression of inflammatory factors including IL-1β, IL-4, IL-6, TNF-α and MPO both in serum and tissues and enhancing immunity by decreasing the production of IgA and IgG.
Conclusion: The DPs play a synergistic anti-UC effect by exerting systemic and local anti-inflammatory and provide an effective oral targeted preparation for the treatment of UC.
Keywords: ulcerative colitis, oral dual-targeted pellets, synergistic treatment, berberine, AM volatile oil