The effect of Mahkota Dewa (Phaleria macrocarpa L.) leaf extract encapsulated in chitosan nanoparticles on inos and COX-2 expression in dextran sodium sulphate-induced colitis mice model

Mahkota Dewa (Phaleria macrocarpa L) is indigenous shrub found in Indonesia commonly used in traditional medicine for its anti-inflammatory effects. This study was conducted to assay Mahkota Dewa leaf extract packaged in chitosan nanoparticles provides superior anti-inflammatory effects on ulcerative colitis induced by dextran sodium sulphate (DSS) compared to Mahkota Dewa leaf extract alone. This study used 36 mice divided into 6 groups: normal, negative control, leaf extract dose 12.5 mg, leaf extract dose 25 mg, leaf extract chitosan nanoparticle dose 6.25 mg, and leaf extract chitosan nanoparticle dose 12.5 mg. Colitis was induced by administering DSS (2 % w/v) through drinking water at 1, 3, and 5 weeks of treatment. At the end of the study, colon samples were taken from the mice for immunohistochemical analysis; the anti-inflammatory effects of each extract were evaluated by determining the expression of cyclooxygenase-2 (COX-2) and induducible mitric oxide synthase (iNOS) score 0 - 4 in the mouse colon using the image G profiler method. Mice administered Mahkota Dewa leaf extract at doses of 12.5 and 25 mg and Mahkota Dewa leaf extract in chitosan nanoparticles at doses of 6.25 and 12.5 mg all demonstrated significantly decreased expression of COX-2 and iNOS (p < 0.001). No significant differences between Mahkota Dewa leaf extract and Mahkota Dewa leaf extract in chitosan nanoparticles were observed. Mahkota Dewa leaf extract and Mahkota Dewa leaf extract in chitosan nanoparticles are equally effective at suppressing COX-2 and iNOS expression in mice with DSS-induced colitis.