Dietary Tributyrin Attenuates Intestinal Inflammation, Enhances Mitochondrial Function, and Induces Mitophagy in Piglets Challenged with Diquat

The study evaluated the effects of butyric acid, in the form of tributyrin on the oxidative stress, inflammation, and mitochondrial function in diquat-challenged pigs. Twenty-four weaned pigs were allocated to four treatments in a 2 × 2 factorial arrangement with the main effects of tributyrin supplementation and diquat challenge. The results showed that supplemental tributyrin increased ( P < 0.05) average daily gain and average daily feed intake of diquat-challenged pigs. Tributyrin elevated ( P < 0.05) the activities of total antioxidant capacity and superoxide dismutase, reduced ( P < 0.05) malondialdehyde content, and increased ( P < 0.05) mRNA levels of copper and zinc superoxide dismutase and manganese-containing superoxide dismutase of diquat-challenged pigs. Tributyrin relieved ( P < 0.05) intestinal inflammation reflected by decreased mRNA abundances of tumor necrosis factor-α, interferon-γ, and interleukin-6 in the intestine. Tributyrin reduced ( P < 0.05) serum diamine oxidase activity and d-lactate content, increased ( P < 0.05) transepithelial electrical resistance, decreased paracellular flux of dextran (4 kDa), and prevented the diquat-induced decrease ( P < 0.05) in the expressions of claudin-1, occludin, and zonula occludens-1. Tributyrin alleviated ( P < 0.05) diquat-induced mitochondrial dysfunction shown by lowered reactive oxygen species, increased mitochondrial membrane potential, and increased adenosine triphosphate content. Furthermore, tributyrin increased ( P < 0.05) expressions of mitophagy proteins (PTEN-induced putative kinase 1 and Parkin), and ratio of light chain 3-II to light chain 3-I in intestine. Collectively, tributyrin attenuated oxidative stress and intestinal inflammation, improved mitochondrial function, and induced mitophagy in diquat-challenged pigs.