Maternal organic selenium supplementation during gestation enhances muscle fiber area and muscle fiber maturation of offspring in porcine model

Background:Organic selenium supplementation during gestation improves the antioxidant status and reproduc-tive performance of sows and increases the antioxidative capacity of the intestines of their offspring.This study was conducted to investigate the effect of maternal basel diet(control)supplemented with an organic Se,2-hydroxy-4-methylselenobutanoic acid(HMSeBA),or inorganic sodium selenite(Na_(2)SeO_(3))during gestation on the antioxidant status and development of muscle in newborn and weaned piglets.Newborn piglets before colostrum intake and weaned piglets were selected for longissimus dorsi(LD)muscle collection and analysis.Results:The results showed that maternal HMSeBA supplementation increased the muscle area and content of Se in the LD muscle of newborn piglets,improved gene expression of selenoproteins,and decreased oxidative status in the LD muscle of both newborn and weaned piglets compared with the control.The expression of muscle development-related genes of newborn piglets in the HMSeBA group was lower than in the control group,whereas the expression of MRF4 in weaned piglets was higher in the HMSeBA group than in the control and Na_(2)SeO_(3)groups.In addition,HMSeBA supplementation decreased the mRNA expressions of myosin heavy chains(MyHC)IIx and MyHC IIb and the percentage of MyHC IIb;increased the expression of PGC-1αin the LD muscle of newborn piglets;increased the gene expression of MyHC IIa;and decreased the protein expression of slow MyHC and the activity of malate dehydrogenase in the LD muscle of weaned piglets compared with the control group.Conclusions:Maternal HMSeBA supplementation during gestation can improve the antioxidative capacity of the muscle of their offspring and promote the maturity of muscle fibres in weaned offspring.

Selenogenome and AMPK signal insight into the protective effect of dietary selenium on chronic heat stress-induced hepatic metabolic disorder in growing pigs

Background:Chronic heat stress(CHS)disrupts hepatic metabolic homeostasis and jeopardizes product quality of pigs.Selenium(Se)may regulate the metabolic state through affect selenoprotein.Thus,we investigate the protective effect of dietary hydroxy-4-methylselenobutanoic acid(HMSeBA)on CHS induced hepatic metabolic disorder in growing pigs,and the corresponding response of selenoprotein.Methods:Forty crossbreed growing pigs were randomly assigned to five groups:control group raised in the thermoneutral environment(22±2℃)with basal diet;four CHS groups raised in hyperthermal condition(33±2℃)with basal diet and supplied with 0.0,0.2,0.4,and 0.6 mg Se/kg HMSeBA,respectively.The trial lasted 28 d.The serum biochemical,hepatic metabolism related enzyme,protein and gene expression and 25 selenoproteins in liver tissue were determined by real-time PCR,ELISA and western blot.Results:CHS significantly increased the rectal temperature,respiration rate,serum aspartate aminotransferase(AST)and low-density lipoprotein cholesterol(LDL-C)of pigs,up-regulated hepatic heat shock protein 70(HSP70)and induced lower liver weight,glycogen content,hepatic glucokinase and glutathione peroxidase(GSH-Px).The CHSinduced liver metabolic disorder was associated with the aberrant expression of 6 metabolism-related gene and 11 selenoprotein encoding genes,and decreased the protein abundance of GCK,GPX4 and SELENOS.HMSeBA improved anti-oxidative capacity of liver.0.4 or 0.6 mg Se/kg HMSeBA supplementation recovered the liver weight,glycogen content and rescue of mRNA abundance of genes related to metabolism and protein levels of GCK.HMSeBA supplementation changed expressions of 15 selenoprotein encoding genes,and enhanced protein expression of GPX1,GPX4 and SELENOS in the liver affected by CHS.CHS alone showed no impact while HMSeBA supplementation increased protein levels of p-AMPKαin the liver.Conclusions:In summary,HMSeBA supplementation beyond nutrient requirement mitigates CHS-induced hepatic metabolic disorder,recovered the liver glycogen content and the processes that are associated with the activation of AMPK signal and regulation of selenoproteins in the liver of growing pigs.