Luteolin and Chrysin Could Prevent <i>E. coli</i> Lipopolysaccharide-Ochratoxin A Combination-Caused Inflammation and Oxidative Stress in In Vitro Porcine Intestinal Model

Abstract

Ochratoxin A (OTA) and lipopolysaccharide (LPS) intake can cause gastrointestinal disorders. Polyphenolic chrysin (CHR) and luteolin (LUT) display anti-inflammatory and antioxidant properties. Porcine intestinal epithelial (jejunal) IPEC-J2 cells were treated with OTA (1 µM, 5 µM and 20 µM), E. coli LPS (10 µg/mL), CHR (1 µM) and LUT (8.7 µM) alone and in their combinations. Cell viabilities (MTS assay) and extracellular (EC) hydrogen-peroxide (H2O2) production (Amplex red method) were evaluated. Intracellular (IC) reactive oxygen species (ROS) were assessed using a 2′-7′dichlorodihydrofluorescein diacetate (DCFH-DA) procedure. ELISA assay was used to evaluate IL-6 and IL-8 secretion. OTA decreased cell viabilities (p 0.001) which could not be alleviated by LUT or CHR (p > 0.05); however, EC H2O2 production was successfully suppressed by LUT in IPEC-J2 cells (p 0.001). OTA with LPS elevated the IC ROS which was counteracted by CHR and LUT (p 0.001). IL-6 and IL-8 secretion was elevated by LPS + OTA (p 0.001) which could be inhibited by LUT (p 0.01 for IL-6; p 0.001 for IL-8). Based on our results, CHR and LUT exerted beneficial effects on IC ROS levels and on cytokine secretion (LUT) in vitro; thus, they might be used as dietary and feed supplements to avoid OTA- and LPS-related health risks.

Keywords

• ochratoxin
• IPEC-J2 cells
• oxidative stress
• interleukins
• flavonoids
• lipopolysaccharide