Lycopene improves maternal reproductive performance by modulating milk composition and placental antioxidative and immune status.

Placental health and milk quality are important for maternal reproductive performance during pregnancy and lactation. Lycopene plays an important role in antioxidation, anti-inflammation and regulating lipid metabolism. The goal of the present study was to investigate the effects of dietary lycopene supplementation in the pig model on reproductive performance, placental health and milk composition during maternal gestation and lactation. In the present study, the litter size of live piglets was increased and the litter size of dead piglets was decreased by lycopene supplementation of the diet of sows. The litter weight at birth and weaning were increased in the lycopene group. Through placental proteomics, we enriched differentially expressed proteins (DEPs), gene ontology (GO) terms, and Kyoto encyclopedia of proteins and genomes (KEGG) pathways involved in immunity, anti-inflammation, antioxidants, and lipid metabolism and transport. Furthermore, in terms of placental health, we analyzed the levels of related enzymes, metabolites and mRNA expression in the placenta. Lycopene was shown to reduce mRNA expression and the levels of placental inflammatory factors, increase the content of immunoglobulin, improve the antioxidant capacity, and improve lipid metabolism and lipid transport in the placenta. In terms of sow milk composition, lycopene increased the levels of immunoglobulins in colostrum and lactose in colostrum and milk. Overall, the results of the present study demonstrate that dietary lycopene supplementation of sows during gestation and lactation improves the reproductive performance to a certain extent; this may be due to lycopene improving the placental health and milk composition of sows.