谷氨酸对脂多糖刺激断奶仔猪肠道能量代谢的影响

本试验旨在研究谷氨酸(Glu)对脂多糖(LPS)刺激断奶仔猪肠道能量代谢的影响。选择24头断奶仔猪分为4个组,分别为对照组、LPS组、LPS+1.0%Glu组和LPS+2.0%Glu组,每组6个重复,每个重复1头猪。于试验第28天,试验组猪注射100μg/kg BW LPS,对照组注射等量的生理盐水,4 h后屠宰,取肠道样品待测。结果表明:1)与对照组相比,LPS刺激导致断奶仔猪空肠三磷酸腺苷(ATP)、腺苷酸池(TAN)含量和能荷(EC)显著降低(P0.05),一磷酸腺苷(AMP)/ATP值显著升高(P0.05);与LPS组相比,LPS+2.0%Glu组显著提高了空肠ATP、二磷酸腺苷(ADP)和TAN含量(P0.05)。2)与对照组相比,LPS刺激导致断奶仔猪回肠柠檬酸合成酶和α-酮戊二酸脱氢酶系活性极显著降低(P0.01),空肠α-酮戊二酸脱氢酶系活性有降低趋势(P=0.092);与LPS组相比,除LPS+1.0%Glu组回肠柠檬酸合成酶活性显著降低(P0.05)外,Glu对空肠和回肠三羧酸循环关键酶活性无显著影响(P0.05)。3)与对照组相比,LPS刺激导致空肠过氧化物酶体增殖物激活受体γ辅激活因子1α(PGC1α)及回肠沉默信号调控因子1(Sirt1)和PGC1α的mRNA表达量极显著降低(P0.01);与LPS组相比,LPS+2.0%Glu组有提高空肠PGC1α(P=0.067)和回肠Sirt1(P=0.053)mRNA表达量的趋势,LPS+1.0%Glu组有提高回肠Sirt1 mRNA表达量的趋势(P=0.070)。由此可见,Glu可以改善LPS刺激导致的肠道能量损耗状态。

Effects of Glutamate on Intestinal Energy Metabolism in the Lipopolysaccharide-Challenged Weaned Piglets

This study was aimed to investigate the effects of glutamate ( Glu) on intestinal energy metabolism in the lipopolysaccharide ( LPS)?challenged weaned piglets. Twenty?four weaned pigs were assigned to four groups as control group, LPS group, LPS+1.0% Glu group and LPS+2.0% Glu group with 6 replicates each and 1 pig in per replicate. On the 28th day of the trial, the piglets in the experimental groups were injected with 100 μg/kg BW LPS, and the piglets in the control group were injected with the same amount of 0.9% NaCl solution. At 4 h post?injection, pigs were slaughtered and intestinal samples were collected for further analysis. The results showed as follows: 1 ) LPS challenge significantly decreased ATP and total adenine nucleotide (TAN) contents and energy charge (P<0.05), but significantly increased the ratio of AMP to ATP (P<0.05) in jejunum compared with the control group; LPS+2.0% Glu group significantly increased the contents of ATP, ADP and TAN ( P<0. 05) in jejunum compared with LPS group. 2) Compared with the control group, LPS challenge had a tendency to decrease the alpha?oxoglutarate dehydrogenase complex activity ( P=0.092) in jejunum and extremely significantly decreased the activities of citrate synthase and alpha?oxoglutarate dehydrogenase complex ( P<0.01) in ileum; compared with LPS group, Glu had no significant effects on the activities of tricarboxylic acid cycle key enzymes ( P>0.05) in jejunum and ileum, except for the citrate syn?thase activity in ileum was significantly reduced in LPS+1.0% Glu group (P<0.05). 3) LPS challenge ex?tremely significantly decreased the mRNA expressions of peroxisome proliferator?activated receptor gamma co?activator?1α ( PGC1α) in jejunum and silent information regulator 1 ( Sirt1) and PGC1α in ileum ( P<0.01) compared with the control group;compared with LPS group, LPS+2.0% Glu group had a tendency to increase the mRNA expressions of PGC1α in jejunum ( P=0.067) and Sirt1 in ileum ( P=0.053) , while LPS+1.0%Glu group had a tendency to increase the Sirt1 mRNA expression in ileum ( P=0.070) . These results indicate that dietary supplementation of Glu can improve energy loss status in LPS injured intestine.