甘氨酰谷氨酰胺二肽对断奶仔猪生长性能及血液激素水平的影响

将21日龄断奶仔猪40头随机分为4个组,每组3个重复,Ⅰ组为对照组,饲喂基础日粮.Ⅱ、Ⅲ、Ⅳ组在基础日粮的基础上分别添加w=0 50%谷氨酰胺、w=0 25%甘氨酰谷氨酰胺、w=0 50%甘氨酰谷氨酰胺.观察甘氨酰谷氨酰胺二肽对断奶仔猪生长性能和血液激素水平的影响.结果表明,添加w=0 25%和w=0 50%的甘氨酰谷氨酰胺组仔猪体质量、采食量和饲料转化率都有所提高,能降低断奶仔猪腹泻率,显著降低血液中皮质醇水平(P<0 05),血液中FT3和FT4水平各组差异不显著.提示断奶仔猪饲粮中添加甘氨酰谷氨酰胺二肽可提高仔猪的生长性能.

甘氨酰谷氨酰胺二肽对黄羽肉鸡肝脏脂肪代谢的影响及其机制的研究

选择360只1日龄优质黄羽肉鸡,随机分为4组,分别饮用凉开水配制的浓度为0、0.01、0.05和0.10mg/L的甘氨酰谷氨酰胺(Gly-Gln)二肽溶液,连续饮用41 d。用甘油三酯试剂盒测定肝脏总甘油三酯的含量。采用相对定量RT-PCR的方法来检测ACC(acetyl-CoA carboxylase)和PPARα(peroxisome proliferatoractivated receptorsα)mRNA的表达水平。试验结果表明:①Gly-Gln二肽能够呈现剂量依赖性的降低肝脏ACC mRNA的表达水平,0.10 mg/L Gly-Gln二肽处理组较对照组差异显著(P<0.05)。②Gly-Gln二肽能够显著上调PPARα基因mRNA的表达水平,其中0.05 mg/L Gly-Gln二肽处理组较对照组差异显著(P<0.05)。③Gly-Gln二肽具有提高肝脏甘油三酯含量的趋势,但差异不显著(P>0.05)。以上结果提示,Gly-Gln二肽能够通过降低肝脏甘油三酯的合成,促进代谢,从而减少脂肪沉积水平。

甘氨酰谷氨酰胺二肽对烧伤大鼠心功能的保护作用

目的了解甘氨酰谷氨酰胺二肽(简称甘谷二肽)对严重烧伤大鼠心肌力学功能的保护作用,并探讨其机制。方法将136只Wistar大鼠分成对照组8只(不予烧伤)、烧伤组32只、谷氨酰胺组32只、甘氨酸组32只、甘谷二肽组32只。后4组均造成30%TBSAⅢ度烧伤。5组大鼠依次给予酪氨酸1.5g·kg^(-1)·d^(-1)、酪氨酸1.5 g·kg^(-1)·d^(-1)、谷氨酰胺1.0 g·kg^(-1)·d^(-1)+酪氨酸0.5 g·kg^(-1)·d^(-1)、甘氨酸0.5 g·kg^(-1)·d^(-1)+酪氨酸1.0g·kg^(-1)·d^(-1)、甘谷二肽1.5 g·kg^(-1)·d^(-1)。伤后12、24、48、72 h检测大鼠心肌组织还原型谷胱甘肽(GSH)、腺苷一磷酸(AMP)、腺苷二磷酸(ADP)、腺苷三磷酸(ATP)、细胞能荷(EC)的含量和主动脉收缩压(AOSP)、主动脉舒张压(AODP)及左心室收缩压(LVSP)、左心室压力变化最大上升速率(+dp/dtmax)。结果后4组大鼠伤后心肌组织GSH、ATP和EC含量以及AOSP、AODP、LVSP、+dp/dtmax检测值普遍低于对照组(P<0.01),AMP、ADP含量则普遍高于对照组(P<0.01)。与烧伤组比较,后3组上述指标均有明显改变。伤后12h甘谷二肽组的GSH含量为(72.7±1.7)μmol/g,高于谷氨酰胺组(67.8±3.8)μmol/g(P<0.01);该时相点EC、AOSP的检测值亦高于谷氨酰胺组(P<0.01)。伤后48 h甘谷二肽组GSH、EC、AOSP的检测值高于甘氨酸组(P<0.01)。结论大鼠烧伤后给予谷氨酰胺、甘氨酸和甘谷二肽,能不同程度改善心肌组织GSH、高能磷酸化合物含量,缓解心肌力学功能的下降。甘谷二肽的疗效明显优于谷氨酰胺或甘氨酸,提示它对烧伤后心脏功能的保护作用具有协同效应。

The Effect of Glycyl-Glutamine Dipeptide Concentration on Enzyme Activity, Cell Proliferation and Apoptosis of Jejunal Tissues from Weaned Piglets

An experiment was conducted in a singly factorial design to study the effect of glycyl-glutamine dipeptide on enzyme activity, cell proliferation and apoptosis of jejunal tissues from weaned piglets at different glycyl-glutamine concentration levels of 2, 4, 10, 20, and 30 mmol L-1, respectively. The glutaminase activity, diamine oxidase (DAO) activity, cell peoliferation, apoptosis, and perotein metabolism were measured by the tissue culture method in vitro using jejunal tissues. The immunohistochemical method was used to study the cell proliferation and apoptosis of jejunal tissues. The results showed that compared to the blank control, the percentage and MOD value of BrdU-positicve cells incubated with glycyl-glutamine dipeptide solution were significantly (P<0.05) increased. Accordingly, the percentage and MOD value of caspase-3-positive cells from tissue incubated with glycyl-glutamine dipeptide were notably lower (P<0.05) than that from the control treatment. The glycyl-glutamine dipeptide increased the glutaminase activity, DAO activity and protein content of jejunal tissues, as the dipeptide concentration was on the rise (P<0.05). These results indicated that glycyl-glutamine dipeptide affected the jejunum development and adaptation of weaned piglets, and the function might be fulfilled by enhancing the glutamine-related enzyme activity, thereby increasing the consumption of glutamine, and then improving the jejunal cell proliferation and suppressing cell apoptosis. The effects of glycyl-glutamine dipeptide relied in a dose-dependent manner, and the maximum effect was achieved at 20-30 mmol L-1 glycyl-glutamine dipeptide.