Transmissible gastroenteritis virus infection decreases arginine uptake by downregulating CAT-1 expression

Transmissible gastroenteritis virus (TGEV) is a coronavirus that causes severe diarrhea in suckling piglets. TGEV primarily targets and infects porcine intestinal epithelial cells, which play an important role in nutrient absorption. However, the effects of TGEV infection on nutrient absorption in swine have not yet been investigated. In this study, we evaluated the impact of TGEV infection on arginine uptake using the porcine small intestinal epithelial cell line IPEC-J2 as a model system. High performance liquid chromatography (HPLC) analyses showed that TGEV infection leads to reduced arginine uptake at 48 hours post-infection (hpi). Expression of cationic amino acid transporter 1 (CAT-1) was attenuated as well. TGEV infection induced activation of phospho-protein kinase C α (p-PKC α), phospho-epidermal growth factor receptor (p-EGFR), and enhanced the expression of caveolin-1, all of which appear to be involved in down-regulating arginine uptake and CAT-1 expression. These results illuminate the relationship between TGEV infection and nutrient absorption, and further our understanding of the mechanisms of TGEV infection.