A biosynthetic pathway for anandamide. Proc Natl Acad Sci U S A

Laboratories of Physiologic Studies, National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.67). 10/2006; 103(36):13345-50. DOI: 10.1073/pnas.0601832103
Source: PubMed

ABSTRACT The endocannabinoid arachidonoyl ethanolamine (anandamide) is a lipid transmitter synthesized and released "on demand" by neurons in the brain. Anandamide is also generated by macrophages where its endotoxin (LPS)-induced synthesis has been implicated in the hypotension of septic shock and advanced liver cirrhosis. Anandamide can be generated from its membrane precursor, N-arachidonoyl phosphatidylethanolamine (NAPE) through cleavage by a phospholipase D (NAPE-PLD). Here we document a biosynthetic pathway for anandamide in mouse brain and RAW264.7 macrophages that involves the phospholipase C (PLC)-catalyzed cleavage of NAPE to generate a lipid, phosphoanandamide, which is subsequently dephosphorylated by phosphatases, including PTPN22, previously described as a protein tyrosine phosphatase. Bacterial endotoxin (LPS)-induced synthesis of anandamide in macrophages is mediated exclusively by the PLC/phosphatase pathway, which is up-regulated by LPS, whereas NAPE-PLD is down-regulated by LPS and functions as a salvage pathway of anandamide synthesis when the PLC/phosphatase pathway is compromised. Both PTPN22 and endocannabinoids have been implicated in autoimmune diseases, suggesting that the PLC/phosphatase pathway of anandamide synthesis may be a pharmacotherapeutic target.

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Available from: George Kunos, Sep 26, 2015
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    • "AEA: anandamide, NAPE: N-acylphosphatidylethanolamine, NAPE-PLD: N-acylphosphatidylethanolamine phospholipase D, GDE1: glycerophosphodiester phosphodiesterase 1, ABHD4: í µí»¼/í µí»½ hydrolase domain containing protein 4, PTPN22: protein tyrosine phosphatase nonreceptor type 22, sPLA2: soluble phospholipase A2, INPP5D: inositol 5-phosphatase, PLC: phospholipase C, FAAH: fatty acid amide hydrolase, COX-2: cycloxygenase 2, LOX-12: arachidonate 12-lipoxygenase, LOX-15: arachidonate 15-lipoxygenase, gp- AEA: glycerophosphoanandamide, p-AEA: phospho-anandamide, lysoNAPE: lyso-N-acylphosphatidylethanolamine, AA: arachidonic acid, ETA: ethanolamine, PG: prostaglandins, PM: prostamides, and 12/15-hAEA: 12/15-hydroxyanandamide. phospholipid precursor N-arachidonoylphosphatidylethanolamine (NAPE) through hydrolysis by a N-arachidonoylphosphatidylethanolamine phospholipase D (NAPE-PLD) [27] in a Ca 2+ -sensitive manner, recent evidence [28] indicates the existence of two parallel, additional, phospholipase C (PLC) and secreted phospholipase A2 (sPLA2)—catalyzed, Ca 2+ -independent pathways. The PLC pathway involves PLC itself and two other enzymes with parallel activity: protein tyrosine phosphatase non-receptor type 22 (PTPN22) and phosphatidylinositol-3,4,5-trisphosphate 5-phosphatase 1 (INPP5D) [29] [30]. The sPLA2 pathway also includes the í µí»¼/í µí»½ hydrolase domain containing protein 4 (ABHD4) and glycerophosphodiesterphosphodiesterase 1 (GDE1) [31] (Figure 1). "
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    ABSTRACT: Endocannabinoids (EC), particularly anandamide (AEA), released constitutively in pain pathways might be accountable for the inhibitory effect on nociceptors. Pathogenesis of neuropathic pain may reflect complex remodeling of the dorsal root ganglia (DRGs) and spinal cord EC system. Multiple pathways involved both in the biosynthesis and degradation of AEA have been suggested. We investigated the local synthesis and degradation features of AEA in DRGs and spinal cord during the development and maintenance of pain in a model of chronic constriction injury (CCI). All AEA synthesis and degradation enzymes are present on the mRNA level in DRGs and lumbar spinal cord of intact as well as CCI-treated animals. Deregulation of EC system components was consistent with development of pain phenotype at days 3, 7, and 14 after CCI. The expression levels of enzymes involved in AEA degradation was significantly upregulated ipsilateral in DRGs and spinal cord at different time points. Expression of enzymes of the alternative, sPLA2-dependent and PLC-dependent, AEA synthesis pathways was elevated in both of the analyzed structures at all time points. Our data have shown an alteration of alternative AEA synthesis and degradation pathways, which might contribute to the variation of AEA levels and neuropathic pain development.
    BioMed Research International 09/2014; 2014(686908):12 pages. DOI:10.1155/2014/686908 · 3.17 Impact Factor
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    • "Several studies show opposing effects of ovarian hormones in the regulation of NAPE-PLD and FAAH [34,49–52] suggesting that it is hard to predict the effects of the hormones involved in the regulation of the oestrous cycle on AEA levels based upon the expression of its metabolic enzymes. Also, a number of other synthetic pathways such as a phospholipase C or a secretory phospholipase A2 have been proposed in neuronal tissues [53,54] and that have not been investigated in reproductive tissues which may be modulating AEA levels. Thus, we thought that direct measurement of AEA content may be more appropriate. "
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    ABSTRACT: Mammalian oviduct acts as a reservoir for spermatozoa and provides an environment in which they may compete for the opportunity to fertilize the oocyte. Whilst in the oviduct spermatozoa undergo capacitation essential for fertilization. Sperm-oviduct interaction is essential for sperm capacitation and is a tightly regulated process influenced by the local microenvironment. Previously we reported that the endocannabinoid anandamide (AEA) regulates sperm release from epithelial oviductal cells by promoting sperm capacitation. The aims of this work were to measure the AEA content and to characterize the main AEA metabolic pathway in the bovine oviduct and determine how these change through the oestrous cycle. In this study, the levels of AEA and two other N-acylethanolamines, N-oleoylethanolamine and N-palmitoylethanolamine, were measured in bovine oviduct collected during different stages of oestrous cycle by ultra high performance liquid chromatography tandem mass spectrometry. Results indicated that intracellular oviductal epithelial levels of all three N-acylethanolamines fluctuate during oestrous cycle. Anandamide from oviductal fluid also varied during oestrous cycle, with the highest values detected during the periovulatory period. Endocannabinoid levels from ipsilateral oviduct to ovulation were higher than those detected in the contralateral one, suggesting that levels of oviductal AEA may be regulated by ovarian hormones. The expression and localization of N-acylethanolamines metabolizing enzymes in bovine oviduct were also determined by RT-PCR, Western blot, and immunohistochemistry but no change was found during the oestrous cycle. Furthermore, nanomolar levels of AEA were detected in follicular fluids, suggesting that during ovulation the mature follicle may contribute to oviductal AEA levels to create an endocannabinoid gradient conducive to the regulation of sperm function for successful fertilization.
    PLoS ONE 08/2013; 8(8):e72521. DOI:10.1371/journal.pone.0072521 · 3.23 Impact Factor
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    • "Author's personal copy (NAPE) (Di Marzo et al., 1994; Okamoto, Morishita, Tsuboi, Tonai, & Ueda, 2004). The second pathway mediates anandamide synthesis in mouse brain and RAW264.7 mouse macrophages, in which phospholipase C catalyzes the cleavage of NAPE to produce phosphoanandamide (Liu et al., 2006), which is then dephosphorylated into anandamide by a protein tyrosine phosphatase PTPN22 (Cohen, Dadi, Shaoul, Sharfe, & Roifman, 1999). This pathway is upregulated by endotoxins in macrophages and may be responsible for the hypotension of septic shock and advanced liver cirrhosis (Liu et al., 2006). "
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    ABSTRACT: A safe and effective antiobesity drug is needed to combat the global obesity epidemic. The discovery of cannabinoids from medicinal herbs has revealed the endocannabinoid system (ECS) in animals and humans, which regulates various physiological activities such as feeding, thermogenesis, and body weight (BW). Although cannabinoid receptors 1 (CB1) antagonists have shown antiobesity efficacies in animal models and in the clinic, they failed to establish as a treatment due to their psychological side effects. Recent studies indicate that CB1 in various peripheral tissues may mediate some of the therapeutic effects of CB1 antagonists, such as improved lipid and glucose homeostasis. It rationalizes the development of compounds with limited brain penetration, for minimizing the side effects while retaining the therapeutic efficacies. A survey of the literature has revealed some controversies about how the ECS affects obesity. This review summarizes the research progresses and discusses some future perspectives.
    Vitamins & Hormones 02/2013; 91:325-68. DOI:10.1016/B978-0-12-407766-9.00014-6 · 2.04 Impact Factor
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