Uridine monophosphate (UMP) is a major nucleotides analogue in mammal’s milk and uridine (UR) is its gastro-intestinal metabolite in vivo. Previous study showed that UMP concentration in mammal milk differs from species and stages of lactation in a particular species. Interestingly, UMP makes up the majority of the total nucleotides composition in sows’ milk. Moreover, numerous studies have showed that pigs have more similar development patterns as humans than other common animal models and are thought to be a proper model for human nutrition. Therefore, assessing the effects of oral administration with UMP and UR on early-weaned piglets thereby starting a point for future studies with single nucleotide supplementation to diets for neonatal pigs and providing reference for infant nutrition plays a great significance.

Researchers from the Institute of Subtropical Agriculture (ISA) of the Chinese Academy of Sciences found that oral administration of UMP and UR affected the small intestinal morphology, improved the intestinal barrier integrity and modified the apoptosis levels of intestine thus reduced the incidence of diarrhea and improved growth performance of weaned piglets. And the intestinal morphological analysis of the piglets showed that UR increased the villus length/crypt depth ratio (V/C) in jejunum, and UR also increased the relative expression of Claudin-3 and E-cadherin in duodenum mucosa.

The researchers also found that the relative mRNA expressions of pyrimidine nucleotide metabolic enzymes, such as UMPS, CMPK1, RRM2, UPRT, CTPS1 and CTPS2, were increased significantly in duodenum mucosa in UR group (P < 0.05). Compared to the control group, both UMP and UR decreased the expression of CAD and RRM2 at jejunum mucosa (P < 0.05). They also found that UMP and UR increased the apoptosis level of intestinal epithelial cells in villus tips of duodenum and jejunum in vivo when compared to the control, respectively. Those results were confirmed by the in vitro experiments. Both UMP and UR decreased the viability of IPEC-J2 cells significantly with values of 10 mM (P < 0.001) and 50 mM (P < 0.001) and extremely increased late apoptosis ratio (%) in cells relative to the vehicle-treated cells (P < 0.001).

The study entitled “Uridine/UMP metabolism and their function on gut in segregated early weaned piglets” was published in Food & Function, and details can be found with https://pubs.rsc.org/en/content/articlelanding/2019/FO/C9FO00360F#!divAbstract. Funding for this study was provided by the National Key Research and Development Program of China (2016YFD0500504), the STS program of Chinese Academy of Sciences (KFJ-STS-QYZX-031) and CAS President’s International Fellowship for Visiting Scientists (2019VBA0015).

Contact: Xin Wu

E-mail: wuxin@isa.ac.cn 

Institute of Subtropical Agriculture, Chinese Academy of Sciences