Development of Colon-Targeted Naringin-Loaded Microbeads in Acetic Acid-Induced Colitis Model in Rats for the Management of Inflammatory Bowel Disease

Abstract

Purpose

The study aimed to develop naringin (NAR)-loaded microbeads coated with Eudragit-S100 polymer for colon-targeted drug delivery, focusing on effectively treating inflammatory bowel disease (IBD).

Methods

NAR-loaded microbeads were formulated by ionic gelation technique. The formulation variables (concentration of chitosan, sodium alginate and sodium tripolyphosphate) were optimized by using Box-Behnken's Design (BBB). Morphological and characterization of the microbeads were performed. Additionally, the therapeutic potential of the microbeads was evaluated in the acetic-acid-induced colitis model by assessing colitis severity, inflammatory markers and histological examination of colonic tissue.

Results

The optimized formulation exhibited a particle size (PS) (258.42 ± 2.98 µm), drug entrapment efficacy (DEE) (87.04 ± 1.67%), % yield (88.45 ± 2.87%), swelling index (SI) (1.21 ± 0.08) in pH 7.4, and zeta potential (-26.24 ± 0.21 mV). Maximum drug release (93.07 ± 3.67%) was achieved in simulated colonic fluid at pH 7.4 over 24 h, following a non-Fickian mechanism involving diffusion, matrix erosion, and bacterial degradation. The results demonstrated that optimized formulation significantly alleviated colitis symptoms by reducing oxidative stress and inflammatory cytokines in colon tissue.

Conclusion

NAR-loaded microbeads, optimized by Box–Behnken design, showed strong therapeutic potential in an acetic acid (AA)-induced colitis model. They reduced tissue necrosis factor-α and myeloperoxidase while improving antioxidant levels such as catalase and superoxide dismutase, offering a promising targeted therapy for IBD.