Identification of biosynthetic precursors for the endocannabinoid anandamide in the rat brain
Identification of biosynthetic precursors for the endocannabinoid anandamide in the rat brain
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DOI：
10.1194/jlr.m700354-jlr200
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发表时间：
2008-01-01
影响因子：
6.5
通讯作者：
Piomelli, Daniele
中科院分区：
文献类型：
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作者：
Astarita, Giuseppe;Ahmed, Faizy;Piomelli, Daniele
Anandamide是一种内源性信号脂质，结合并激活大脑和外周组织中的大麻素受体。anandamide的内源性前体n-花生四烯酰基磷脂酰乙醇胺（NArPEs）是一类复杂的甘油磷脂，它是由花生四烯酰基在n-酰基转移酶的催化下，在磷脂酰胆碱的sn-1位置与磷脂酰乙醇胺的伯胺之间发生交换反应而产生的。一种精确表征的分子组成的NArPE物种产生阿南达胺尚未报道。在本研究中，我们利用液相色谱耦合电喷雾离子阱质谱法鉴定了主要的内源性NArPE物种，它们主要含有sn-1烯基（C16:0, C18:0, C18:1）和甘油主链sn-2位置的单不饱和（C18:1）或多不饱和（C20:4, C22:4, C22:6）酰基。使用大鼠脑颗粒组分，我们观察到在37℃孵育30分钟后，NArPEs和anandamide形成的钙依赖性增加。此外，一项针对性的脂质组学分析表明，Ca2+特异性地刺激了含有pufa的NArPE物种的形成。
Anandamide is an endogenous signaling lipid that binds to and activates cannabinoid receptors in the brain and peripheral tissues. The endogenous precursors of anandamide, N-arachidonoyl phosphatidylethanolamines (NArPEs), are a family of complex glycerophospholipids that derive from the exchange reaction of an arachidonoyl group between the sn-1 position of phosphatidylcholine and the primary amine of phosphatidylethanolamine catalyzed by N-acyl transferase activity. A precise characterization of the molecular composition of NArPE species generating anandamide has not yet been reported. In the present study, using liquid chromatography coupled to electrospray ionization ion-trap mass spectrometry, we identified the major endogenous NArPE species, which mainly contained sn-1 alkenyl groups (C16:0, C18:0, C18:1) and monounsaturated (C18:1) or polyunsaturated (C20:4, C22:4, C22:6) acyl groups at the sn-2 position of the glycerol backbone. Using rat brain particulate fractions, we observed a calcium-dependent increase in both NArPEs and anandamide formation after incubation at 37 degrees C for 30 min. Furthermore, a targeted lipidomic analysis showed that Ca2+ specifically stimulated the formation of PUFA-containing NArPE species.