Uso de nanoemulsão de curcumina em modelo animal de dano intestinal induzido por indometacina

Abstract

Micronization emerges as a strategy to improve physical properties and consequently the absorption of natural products with potential health benefits, such as curcumin. Given this context, this study evaluated the anti-inflammatory and intestinal modulation effects of a curcumin-loaded nanoemulsion in an animal model of indomethacin-induced intestinal damage. Nanoemulsions containing curcumin were prepared by the spontaneous emulsification method with castor oil, soybean lecithin, and curcumin in ethanol (≥99.8%, HPLC grade). The nanoemulsion was then characterized by dynamic light scattering (DLS) and zeta potential, and its morphology was evaluated by scanning electron microscopy (SEM). Its stability was tested under different pH conditions (2.0, 7.0, and 8.0) and storage temperatures (8, 30, and 37°C) at time points of 0, 7, 14, 21, and 28 days. For the animal experiments, 36 male Mus musculus mice (C57BL/6) were used. The animals were randomly divided into 4 groups of 9 mice for an adaptation phase of 7 days, pre-induction for 10 days, followed by intestinal damage induction + treatment for 4 days. Its impact on intestinal inflammation was assessed through macroscopic, histopathological, and metagenomic analyses. The results were compiled into graphs and tables; statistical analysis was performed considering a significance level of 0.05. In the present study, a stable nanoemulsion with a size of 409.8 nm, PDI of 0.132, and zeta potential of -18.8 mV was obtained. However, the emulsions lost charge in pH 2, showing instability in acidic environments (p<0.05). In the animal experiment, it was demonstrated that curcumin reduced inflammation by 50% and lymphoid hyperplasia by 100% (p<0.05). The nanoemulsion did not show a significant improvement in indomethacin-induced intestinal inflammation. Metagenomic analysis showed that indomethacin reduced the relative frequency of the Firmicutes phylum (p<0.05). The group treated with curcumin nanoemulsion showed a higher relative abundance of the Lactobacillus genus (p<0.05). In conclusion, the efficacy of curcumin in reducing intestinal inflammation was confirmed. Although the curcumin nanoemulsion did not show a functional effect on intestinal damage, it was relevant in modulating the intestinal microbiota. Therefore, further studies are needed to improve the nanoemulsion formulation and enable its future application in the treatment of inflammatory bowel disease.