Grape seed proanthocyanidins supplementation attenuates diquat-induced intestinal barrier damage in weaned pigs

Grape seed proanthocyanidins (GSP) is a kind of plant polyphenols with a wide variety of biological activities. In the present study, we evaluated whether GSP can alleviate intestinal injury in weaned pigs injected with diquat.

A total of 32 pigs were randomly assigned to four groups (n = 8): (1) nonchallenged control; (2) control + 50 mg/kg GSP; (3) diquat-treated control and (4) diquat + 50 mg/kg GSP. On the morning of day 15, the pigs were injected with diquat (10 mg per kg body weight) or saline, and were then killed to obtain the serum and intestinal segments 7 days later.

The results showed that GSP addition decreased (P < 0.05) the urea concentration and increased (P < 0.05) the total superoxide dismutase activity in serum of diquat-challenged pigs. GSP increased (P < 0.05) the ileal villus height and duodenal and ileal villus height to crypt depth ratio in diquat-challenged pigs. GSP supplementation not only down-regulated (P < 0.05) the cysteinyl aspartic acid-protease-3 (Caspase-3), Caspase-8 and Caspase-9 expression levels but also up-regulated (P < 0.05) the expression levels of Claudin-1 and zonula occludens-1 in the small intestine. Furthermore, GSP supplementation increased (P < 0.05) the cecal Lactobacillus, Bifidobacterium and Bacillus populations and colonic Bacillus population in diquat-challenged pigs.

These findings suggest that GSP can attenuate diquat-induced intestinal mucosa disruption, which was linked to enhancement of the antioxidant capacity and improvement in intestinal microbiota.