Effects of dietary leucine supplementation on the hepatic mitochondrial biogenesis and energy metabolism in normal birth weight and intrauterine growth-retarded weanling piglets

BACKGROUND/OBJECTIVES: The study was conducted to evaluate the effects of dietary leucine supplementation on mitochondrial biogenesis and energy metabolism in the liver of normal birth weight (NBW) and intrauterine growth-retarded (IUGR) weanling piglets. MATERIALS/METHODS: A total of sixteen pairs of NBW and IUGR piglets from sixteen sows were selected according to their birth weight. At postnatal day 14, all piglets were weaned and fed either a control diet or a leucine-supplemented diet for 21 d. Thereafter, a 2 × 2 factorial experimental design was used. Each treatment consisted of eight replications with one piglet per replication. RESULTS: Compared with NBW piglets, IUGR piglets had a decreased (P < 0.05) hepatic adenosine triphosphate (ATP) content. Also, IUGR piglets exhibited reductions (P < 0.05) in the activities of hepatic mitochondrial pyruvate dehydrogenase (PDH), citrate synthase (CS), α-ketoglutarate dehydrogenase (α-KGDH), malate dehydrogenase (MDH), and complexes I and V, along with decreases (P < 0.05) in the concentration of mitochondrial DNA (mtDNA) and the protein expression of hepatic peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α). Dietary leucine supplementation increased (P < 0.05) the content of ATP, and the activities of CS, α-KGDH, MDH, and complex V in the liver of piglets. Furthermore, compared to those fed a control diet, piglets given a leucine-supplemented diet exhibited increases (P < 0.05) in the mtDNA content and in the mRNA expressions of sirtuin 1, PGC-1α, nuclear respiratory factor 1, mitochondrial transcription factor A, and ATP synthase, H+ transporting, mitochondrial F1 complex, β polypeptide in liver. CONCLUSIONS: Dietary leucine supplementation may exert beneficial effects on mitochondrial biogenesis and energy metabolism in NBW and IUGR weanling piglets.

EFFECTS OF SELENIUM ENRICHED PROBIOTICS ON ANTIOXIDATIVE ACTIVITIES AND IMMUNE FUNCTIONS IN WEANLING PIGLETS / 营养学报

Objective: To investigate the effects of selenium enriched probiotics on antioxidative activities and immune functions in weanling piglets. Methods: Twenty-four healthy weanling piglets (Duroc?Landrace?Yorkshire ) were divided into 3 groups. One served as control group (C) and two were supplemented different selenium (Se) sources namely selenium enriched probiotics (T1) and Na selenite (T2) as test groups respectively . The experiment lasted for 60 days. The blood GSH-Px activity, blood Se concentration, serum superoxide dismutase (SOD) activity, serum malonaldehyde (MDA) level, serum antibody level of swine fever, and the tissue content of selenium were determined. Results: Blood GSH-Px , Se concentration and serum SOD activity of T1, T2 groups were higher than those of control group after 60 d Se supplementation, and serum MDA content was markedly lower than control group. At the same time, the serum antibody level of swine fever, the tissue content of selenium in T1, T2 group were much higher than control group, and T1 group was higher than T2 group. Conclusion: Organic Se supplementation could significantly enhance immune function and antioxidative activities of weanling piglets.