P507 - EFFECTIVE PREBIOTICS REDUCE WATER INFLUX INTO THE CECAL LUMEN AND IMPROVE STOOL CONSISTENCIES IN LIQUID DIET-FED RATS

P507

EFFECTIVE PREBIOTICS REDUCE WATER INFLUX INTO THE CECAL LUMEN AND IMPROVE STOOL CONSISTENCIES IN LIQUID DIET-FED RATS

Y. Miki^1,*, I. Yamaoka¹

¹OS-1 Division, Otsuka Pharmaceutical Factory, Inc., Naruto, Japan

Rationale: This study investigates the impact of pectin, a prebiotic, on stool consistencies in rats under a liquid diet, addressing the clinical question of whether pectin can help prevent diarrhea associated with enteral nutrition.

Methods: Seven types of test meals were fed to male Wistar rats (each group n = 9) for 7 days ad libitum. The test meals were as follows: Standard Solid-Diet; HF (high-fat liquid diet); HF-LMP (HF containing low methoxy pectin); HF-HMP (HF containing high methoxy pectin); LF (low-fat liquid diet); LF-LMP; LF-HMP. Stool consistencies were observed during the test meal period. Microarray, qPCR and immunostaining of cecum tissues, as well as colloid osmotic pressure of cecum contents, were also measured.

Results: Diarrhea was clearly observed in the HF, HF-HMP, LF, and LF-HMP groups (groups without LMP). On the other hand, the HF-LMP and LF-LMP groups (groups with LMP) were able to maintain favorable stool consistencies at different fat content ratios. In the microarray analysis, Aqp8 (aquaporin-8, water-transporting gene) was present in the gene group that significantly decreased in the groups with favorable stool consistencies compared to the diarrhea groups. A quantitative and histological analysis of Aqps using qPCR and immunostaining revealed an evident decrease of AQP8 in the groups with LMP. Furthermore, the cecum content of the groups with LMP had lower colloid osmotic pressure levels compared to that of the groups without LMP.

Conclusion: Under a liquid diet, the colloid osmotic pressure in the intestinal lumen increases notably, inducing an AQP8-dependent water influx into the intestinal lumen that results in diarrhea. However, prebiotic LMP inhibits the elevation of colloid osmotic pressure in the liquid diet at different fat content ratios, and promotes normal fecal excretion.

Disclosure of Interest: Y. Miki Other: An employee of Otsuka Pharmaceutical Factory, Inc., I. Yamaoka Other: An employee of Otsuka Pharmaceutical Factory, Inc.