Expressiong of Slc6a19 and Slc1a5. Data are expressed as mean 6 SD, n = 5. 1HBW, high birth weight; 2 LBW, low birth weight. doi:10.1371/journal.pone.0050921.gNeutral Amino Acids in Mini-PigletsFigure 2. Protein abundances of jejunum B0AT1 (A) and ASCT2 (B) in sucking Huanjiang mini-JI 101 web piglets with HBW1 and LBW2 from days 0 to 21 of age. Samples were obtained from Huanjiang mini-pigs on Days 0, 7, 14 and 21 of age, respectively. The protein amounts of B0AT1 and ASCT2 were normalized using b-actin as an inner control. Values without a common letter on bars differ (P,0.05). The P value showed the effects of age, BW, and age and BW interaction on protein expressiong of B0AT1 and ASCT2. Data are expressed as mean 6 SD, n = 5. 1HBW, high birth weight; 2LBW, low birth weight. doi:10.1371/journal.pone.0050921.g[3]. In addition, the LBW pigs exhibited less lean mass and more fat at market Arg8-vasopressin custom synthesis weight than the HBW pigs [4]. Here our data indicated that the LBW piglets had alterations in the contents of NAA in plasma, liver and skeletal muscle during the early sucking period, with lower contents in plasma and higher contents in liver and skeletal muscle of some NAA. Moreover, age6BW interaction effects were observed for plasma, liver and skeletal muscle contents of some NAA in sucking piglets. It has been reported that arterial concentration of Ile was significantly reduced in the IUGR sheep fetuses [14]. According to our results, there were no differences in the contents of Ile in plasma and muscle between the HBW and LBW piglets, but a higher content in liver of LBW piglets. Amino acids and peptides are mainly absorbed by the enterocytes of the small intestine, with the proximal 18297096 jejunum as the major absorption site of AA and peptides. However, other studies showed that, compared with the normal BW piglets, IUGR reduced the height of villi and the average number of villi per unit area, which resulted in a lower intestinal surface area for nutrient absorption [28]. Moreover, the LBW piglets’ small intestine exhibited signs of immaturity, which may reduce the digestive and absorptive capacities [12]. To test whether the alterations of NAA contents in plasma, liver and skeletal muscle were related to the absorption process, the mRNA expression levels and protein abundances of two major NAA transporters, including Slc6a19 (B0AT1) and Slc1a5 (ASCT2), were examined. Consistent with the content alterations of NAA, the expression levels of both Slc6a19 (B0AT1) and Slc1a5 (ASCT2) were changed at early suckling period. These findings suggested a relationship between intestine dysfunction and physiological change of other organs in the LBW piglets. Further work should be conducted to confirm this relationship. Other studies demonstrated that LBW in piglets correlates with decreased survival rates [2,5,6]. Two-thirds of piglets with BW lessthan 0.8 kg died during suckling, the mortality for piglets with BW of 0.81 to 1.0 kg is 34 and less than 10 for piglets above 1.6 kg BW [6]. More than Seventy-five percent of post-natal deaths for LBW piglets occurred within the first week after birth. According to the results of the present study, LBW piglets had alterations in contents of some of NAA in plasma, liver and skeletal muscle, and lower jejunal expression of Slc6a19 (B0AT1) and Slc1a5 (ASCT2) during the first week after birth, which suggested that the intestinal dysfunction may be one of the reason for the high mortality of LBW piglets. Other studies showed that t.Expressiong of Slc6a19 and Slc1a5. Data are expressed as mean 6 SD, n = 5. 1HBW, high birth weight; 2 LBW, low birth weight. doi:10.1371/journal.pone.0050921.gNeutral Amino Acids in Mini-PigletsFigure 2. Protein abundances of jejunum B0AT1 (A) and ASCT2 (B) in sucking Huanjiang mini-piglets with HBW1 and LBW2 from days 0 to 21 of age. Samples were obtained from Huanjiang mini-pigs on Days 0, 7, 14 and 21 of age, respectively. The protein amounts of B0AT1 and ASCT2 were normalized using b-actin as an inner control. Values without a common letter on bars differ (P,0.05). The P value showed the effects of age, BW, and age and BW interaction on protein expressiong of B0AT1 and ASCT2. Data are expressed as mean 6 SD, n = 5. 1HBW, high birth weight; 2LBW, low birth weight. doi:10.1371/journal.pone.0050921.g[3]. In addition, the LBW pigs exhibited less lean mass and more fat at market weight than the HBW pigs [4]. Here our data indicated that the LBW piglets had alterations in the contents of NAA in plasma, liver and skeletal muscle during the early sucking period, with lower contents in plasma and higher contents in liver and skeletal muscle of some NAA. Moreover, age6BW interaction effects were observed for plasma, liver and skeletal muscle contents of some NAA in sucking piglets. It has been reported that arterial concentration of Ile was significantly reduced in the IUGR sheep fetuses [14]. According to our results, there were no differences in the contents of Ile in plasma and muscle between the HBW and LBW piglets, but a higher content in liver of LBW piglets. Amino acids and peptides are mainly absorbed by the enterocytes of the small intestine, with the proximal 18297096 jejunum as the major absorption site of AA and peptides. However, other studies showed that, compared with the normal BW piglets, IUGR reduced the height of villi and the average number of villi per unit area, which resulted in a lower intestinal surface area for nutrient absorption [28]. Moreover, the LBW piglets’ small intestine exhibited signs of immaturity, which may reduce the digestive and absorptive capacities [12]. To test whether the alterations of NAA contents in plasma, liver and skeletal muscle were related to the absorption process, the mRNA expression levels and protein abundances of two major NAA transporters, including Slc6a19 (B0AT1) and Slc1a5 (ASCT2), were examined. Consistent with the content alterations of NAA, the expression levels of both Slc6a19 (B0AT1) and Slc1a5 (ASCT2) were changed at early suckling period. These findings suggested a relationship between intestine dysfunction and physiological change of other organs in the LBW piglets. Further work should be conducted to confirm this relationship. Other studies demonstrated that LBW in piglets correlates with decreased survival rates [2,5,6]. Two-thirds of piglets with BW lessthan 0.8 kg died during suckling, the mortality for piglets with BW of 0.81 to 1.0 kg is 34 and less than 10 for piglets above 1.6 kg BW [6]. More than Seventy-five percent of post-natal deaths for LBW piglets occurred within the first week after birth. According to the results of the present study, LBW piglets had alterations in contents of some of NAA in plasma, liver and skeletal muscle, and lower jejunal expression of Slc6a19 (B0AT1) and Slc1a5 (ASCT2) during the first week after birth, which suggested that the intestinal dysfunction may be one of the reason for the high mortality of LBW piglets. Other studies showed that t.
