The effects of enteral nutrition supplemented with octanoic acid on LPS-induced intestinal injury: role of PPARγ/STAT-1/MyD88 pathway

Objective Enteral nutrition (EN) is the key therapy in septic patients. Different formulas of EN have various effects on gastrointestinal sepsis. Therefore, we investigated the effects of EN supplemented with octanoic acid (OA) on lipopolysaccharide (LPS) induced intestinal injury and explored the potential mechanism. Methods First, to investigate the effects of EN supplemented with OA on LPS-induced intestinal injury, rats were randomly divided into four groups: the sham, LPS, LPS + EN, and LPS + EN + OA groups. Then, to explore whether EN supplemented with OA can prevent LPS-induced intestinal injury via the PPARγ/STAT-1/MyD88 pathway, rats were randomly divided into five groups: the sham, LPS, LPS + EN + OA, LPS + EN + OA +SR202, and LPS + pioglitazone groups. All rats received nutritional support for three days. We examined the serum levels of inflammatory factors, pathological changes, goblet cell density, intestinal tight junction protein expression, and the PPARγ/STAT-1/MyD88 pathway in the ileum and colon. In addition, the effect of OA on intestinal epithelium injury was also explored in vitro. Results EN supplemented with OA significantly decreased the serum levels of inflammatory factors and prevented intestinal barrier dysfunction compared with EN alone (P < 0.05). Inhibiting the PPARγ/STAT-1/MyD88 pathway exacerbated effects of EN supplemented with OA on intestinal injury (P < 0.05). Activation of the PPARγ/STAT-1/MyD88 pathway prevented intestinal injury (P < 0.05). OA also exerted a similar effect on intestinal epithelium injury in vitro. Conclusion EN supplemented with OA prevents LPS-induced intestinal injury via the PPARγ/STAT-1/MyD88 pathway.