Anti-Inflammatory Local Effect of Hydroxytyrosol Combined with Pectin-Alginate and Olive Oil on Trinitrobenzene Sulfonic Acid-Induced Colitis in Wistar Rats

ABSTRACT

Purpose: Evaluate the efficacy of hydroxytyrosol in the local treatment of inflammatory colitis. Currently, the existing treatments for inflammatory bowel diseases does not cure the disease and it is associated with high rates of side effects and complications. Hydroxytyrosol is a phenyl-ethyl-alcohol derived from the hydrolysis of oleuropein and present in olive oil, previous studies have demonstrated the anti-inflammatory effect of dietary hydroxytyrosol supplement, with no toxicity. Materials & Methods: Colitis has been induced by using Trinitrobenzene Sulfonic Acid at 40 rats. They were divided into four groups randomly: 10 rats without treatment; 10 rats with pectin/alginate mixture; 10 rats treated with pectin/alginate + olive oil; 10 rats treated with pectin/alginate + olive oil + hydroxytyrosol. Animals were sacrificed 10 days after induction of trinitrobenzene sulfonic acid, receiving 5 days of continuous treatment. Samples of the rectal area were studied and observed under a microscope to determine the damage by Hunter scoring modified, assessing inflammatory infiltration, number of intestinal walls involved, damage to the mucosal architecture, and edema. Results: When the rectum was analyzed in a global way, nonsignificant differences were observed; however, when performing an individualized analysis, statistically significant differences in the inflammatory infiltrate are present in the samples, which were evaluated using the ANOVA and Student-T statistics. Conclusions: Local treatment with the natural antioxidant hydroxytyrosol combined with pectin/alginate and olive oil of inflammatory bowel disease has been shown to be effective against inflammatory infiltration of TNBS-induced colitis.

Keywords::

• colitis
• hydroxytyrosol
• inflammatory bowel disease
• olive oil
• pectin/alginate

DECLARATION OF INTEREST

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Acknowledgments

This research was supported by the Spanish Ministry of Economy, Industry and Competitiveness and cofunded by a European Social Fund (ESF) (Ramon y Cajal Programme RyC 2012–10456; project AGL2013–48291-R and project AGL2016-79088-R) and A. Bermúdez-Oria received funding from the Spanish FPI program (MEIC) (BES-2014-068508).

Research involving human participants and/or animals

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. The animals have been treated throughout the experimental process according to the Council of Europe agreements on the protection of animals used in animal experiments.

This article does not contain any studies with human participants performed by any of the authors.