(P03-061-23) Effect of Crude Blueberry Phenolic Extracts on Improving Gut Barrier Integrity and Inflammation In Vitro

Objectives: The swine industry weans piglets from sows as early as three weeks when they start to digest complex feed. However, an immature gastrointestinal tract coupled with stressors results in post-weaning diarrhea (PWD). Nutraceutical feed containing functional compounds has been recently touted as a new therapy. Here, the capability of blueberry phenolic extracts to mitigate gut barrier disruption using porcine intestinal epithelial cells (IPEC-J2) was evaluated.

Methods: Blueberry phenolic compounds (BPE) were extracted and quantified via LC-MS. Porcine intestinal (IPEC-J2) cells were pretreated with 1 or 2.5 ug/ml BPE for 24 h and challenged with 10 ug/ml lipopolysaccharide for 6 h. Antioxidant status was screened via a catalase (CAT) enzyme ELISA. Paracellular permeability was measured via FITC-dextran. Relative mRNA abundance of proinflammatory cytokines and tight junction proteins was determined through RT-PCR and tight junction protein expression was confirmed by western blot analysis.

Results: Pretreatment with 1 ug/ml BPE (p = 0.0005) preserved CAT activity. Reduced paracellular permeability of FITC-dextran was observed in a dose-dependent manner (p =0.002, p < 0.001 respectively). 1 ug/ml BPE increased the relative abundance of occludin (p= 0.026) and reduced IL-8 expression (p = 0.046) following LPS challenge. LPS reduced gene expression of occludin, but pretreatment was able to preserve the protein levels (p =0.016, p = 0.0382).

Conclusions: Preliminary results indicate that addition of blueberry phenolic compounds can be an effective management plan for PWD through the conservation of antioxidant status, reduction of intestinal permeability and inflammation, and preservation of tight junction proteins. The study must be replicated in vivo for physiologically relevant results.

Funding Sources: USDA-NIFA Foundation Award 2022