Enantiomer-specific selection of amino acids.
Enantiomer-specific selection of amino acids.
复制标题
氨基酸的对映体特异性选择。
DOI：
10.1007/s00726-013-1595-9
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发表时间：
2013
期刊：
影响因子：
3.5
通讯作者：
deAraujo,IvanE
中科院分区：
文献类型：
--
作者：
Ren,Xueying;Tellez,LuisA;deAraujo,IvanE
膳食摄入的氨基酸影响几种生理功能，包括控制胃肠动力，胰腺分泌和食欲。然而，调节对某些氨基酸类型的行为偏好的生物学机制仍然知之甚少。我们测试了这一假设，即在小鼠中，给定的生糖氨基酸增加葡萄糖利用的效力反映了其奖励特性。我们发现：（1）在长期而非短期偏好性试验中，L-丙氨酸和L-丝氨酸比它们的对映体更受青睐，而L-苏氨酸对D-苏氨酸没有这种效应;（2）这些行为模式与α-氨基酸促进呼吸交换率增加的能力密切相关，使得那些，并且只有那些，l-氨基酸能够促进呼吸交换率的增加，优于其异构体;（3）这些行为偏好独立于味觉的影响，因为味觉缺陷Trpm 5基因敲除小鼠表现出与野生型小鼠非常相似的摄食反应。我们的结论是，促进呼吸交换率增加的能力增强了营养相关的氨基酸的奖励价值，并建议底物利用率和氨基酸偏好之间的机械联系。
Dietary intake ofl-amino acids impacts on several physiological functions, including the control of gastrointestinal motility, pancreatic secretion, and appetite. However, the biological mechanisms regulating behavioral predilections for certain amino acid types remain poorly understood. We tested the hypothesis that, in mice, the potency with which a given glucogenic amino acid increases glucose utilization reflects its rewarding properties. We have found that: (1) during long-, but not short-, term preference tests,l-alanine andl-serine were preferred over theird-enantiomer counterparts, while no such effect was observed forl-threonine vs.d-threonine; (2) these behavioral patterns were closely associated with the ability ofl-amino acids to promote increases in respiratory exchange ratios such that those, and only those,l-amino acids able to promote increases in respiratory exchange ratios were preferred over theird-isomers; (3) these behavioral preferences were independent of gustatory influences, since taste-deficientTrpm5knockout mice displayed ingestive responses very similar to those of their wild-type counterparts. We conclude that the ability to promote increases in respiratory exchange ratios enhances the reward value of nutritionally relevant amino acids and suggest a mechanistic link between substrate utilization and amino acid preferences.