Maternal organic selenium supplementation alleviates LPS induced inflammation, autophagy and ER stress in the thymus and spleen of offspring piglets by improving the expression of selenoproteins

Thymus and spleen are the main reservoir for T lymphocytes, which can regulate innate immune response and provides protection against pathogens and tissue damage. Oxidative stress, excessive inflammation, abnormal autophagy and endoplasmic reticulum (ER) stress can all lead to dysfunction of thymus and spleen. This study was conducted to investigate the effect of maternal 2-hydroxy-4-methylselenobutanoic acid (HMSeBA, an organic Se source) supplementation during pregnancy on the selenoproteins expression, inflammation, ER stress and autophagy of their young offspring’s thymus and spleen. Thirty sows were randomly assigned to receive one of the following two diets during gestation: control diet (Control, basal diet, n = 15) or HMSeBA supplemented diet (HMSeBA, basal diet + 0.3 mg Se/kg as HMSeBA, n = 15). Tissues of thymus and spleen were collected from the offspring at birth and weaning after lipopolysaccharide challenge. Results showed that maternal HMSeBA supplementation significantly up-regulated the gene expression of selenoproteins in the thymus and spleen of newborn piglets compared with basal diet (p < 0.05), as well as the protein abundance of GPX1 and GPX4 (p < 0.05). In addition, maternal HMSeBA supplementation effectively decreased the expression of inflammation and autophagy related proteins in the thymus and spleen of newborn piglets as compared with control group (p < 0.05). In weaning piglets, maternal HMSeBA significantly increased the antioxidative capacity of thymus and spleen (p < 0.05), and reversed LPS induced MDA content as compared with control group (p < 0.05). Furthermore, maternal HMSeBA supplementation during gestation reversed the activation of MAPK/NF-κB pathway, ER stress and autophagy induced by LPS challenge in the thymus and spleen of weaning piglets (p < 0.05). In conclusion, maternal HMSeBA supplementation during gestation could decrease the level of inflammation, autophagy and ER stress in the thymus and spleen of young offspring by improving the antioxidative capacity and selenoproteins expression in these tissues. Therefore, maternal HMSeBA supplementation during gestation might be benefit for the immune function of their offspring by alleviating inflammation, autophagy and ER stress levels in the thymus and spleen. This study showed more evidences for the function of Se on mater-offspring integrated nutrition.