# Monitoring of Vitamin C Plasma Levels in a Reversible Model of Malabsorption Generated in Mice by Ebulin-f

## TL;DR

Researchers developed a reversible mouse model of intestinal malabsorption using ebulin-f and used vitamin C plasma levels to monitor absorption changes over time.

## Contribution

A novel reversible model of intestinal malabsorption using sublethal ebulin-f doses in mice is introduced and validated.

## Key findings

- Ebulin-f caused reversible intestinal damage in mice, with peak damage on day 3 and regeneration by day 22.
- Vitamin C absorption increased significantly on days 1 and 3 post-treatment compared to controls.
- The model shows potential for studying inflammatory bowel disease and reducing animal use in research.

## Abstract

The development of reversible animal models for the study of intestinal pathologies is essential to reduce the number of animals used in research and to better understand disease mechanisms. In this study, we present a reversible model of intestinal malabsorption through the administration of sublethal doses of ebulin-f, a ribosome-inactivating protein, and validate its usefulness by monitoring vitamin C absorption. The scientific community increasingly recognizes the importance of rationalizing experimental designs, optimizing treatment protocols, and minimizing the use of animals in research models. Thus, new methodologies are needed to minimize invasive sampling and to develop reversible animal models that recover physiologically post-study. Such models are essential for in vivo studies of human pathologies. Sublethal doses of ebulin-f (2.5 mg/kg) administered intraperitoneally to female Swiss CD1 mice (n = 6 per group) can cause reversible intestinal alterations in the small intestine, which offer the possibility of having a valuable reversible study model of malabsorption for the investigation of this syndrome. To verify whether nutrient absorption is altered, we used vitamin C as a traceable nutrient that can be quantified in the blood. Peripheral blood samples were collected through the retro-orbital area at 30, 80, 120, 180, and 1440 min post-administration, treated with DTT and MPA, and analyzed using a validated UV/Vis–HPLC method to indirectly determine vitamin C absorption by enterocytes. Pharmacokinetic analysis revealed significantly increased vitamin C absorption on days 1 and 3 post-treatment (AUC values of 3.65 × 104 and 7.10 × 104, respectively) compared to control (0.94 × 104), with partial recovery by day 22 (3.27 × 104). Blood concentration profiles indicate that intestinal damage peaks at day 3, followed by significant regeneration by day 22, establishing this as a viable reversible model for inflammatory bowel disease research.