Oleamide

Unsaturated fatty acid amides represent a unique class of signaling molecules within the central nervous system (Lerner et al 1994, Cravatt et al 1995, Basile et al 1999). The fatty acid amides appear to be simple molecules with a great deal of diversity based on differing alkane chain lengths, stereochemistry, and locations of double bonds (Cravatt et al 1995). 

Oleamide, a lipid originally named cerebrodiene, was first iso lated from partially sleep-deprived cats (Lerner et al 1994). The molecule, with the chemical formula C18H35NO, is a long-chain base structurally related to sphingosine and sphinganine (Lerner et al 1994). Oleamide, or cerebrodiene, is chemically characterized as cis-9,10-octadecenoamide (Cravatt et al 1995). Oleamide is degraded by the brain enzyme fatty acid amide hydrolase (FAAH), which also degrades anandamide (Cravatt et al. Nature 1996). 

Synthetic cts-9,10-octadecenoamide induced 1-2.5 h of sleep in rats when injected intraperitoneally in doses between 5 and 50 mg (Cravatt et al 1995). Doses between 5 and 150 mg reduce sleep latency in rats while sleep-deprived rats develop two- to three-fold increases in CSF oleamide levels (Basile et al 1999). 

See Boring 1996 Lerner 1994 for oleamide cannabinoid activity. Anti-cancer Activity See Di Marzo et al Palmitoylethanolamide Inhibits the Expression of Fatty Acid Amide Hydrolase and Enhances the anti-proliferative Effect of Anandamide in Human Breast Cancer Cells. Biochem J. (2001) 358 (Pt 1) 249-55. 

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Although, the enzymatic reaction of esters with amines or ammonia have been well documented, the corresponding aminolysis with carboxylic acids are rarer, because of the tendency of the reactants to form unreactive salts. For this reason some different strategies have been used to avoid this problem. Normally, this reaction has been used for the preparation of amides of industrial interest, for instance, one of the most important amides used in the polymer industry like oleamide has been produced by enzymatic amidation of oleic acid with ammonia and CALB in different organic solvents [10]. 

Inhibition of [ CJ-oleamide hydrolysis in rat liver plasma membranes. 

Applications Shake-flask extraction nowadays finds only limited application in polymer/additive analysis. Carlson et al. [108] used this technique to extract antioxidants from rubber vulcanisates for identification purposes (NMR, IR, MS). Wrist-action shaking at room temperature was also used as the sample preparation step for the UV and IR determination of Ionol CP, Santonox R and oleamide extracted from pelletised polyethylene using different solvents [78]. BHT could be extracted in 98 % yield from powdered PP by shaking at room temperature for 30 min with carbon disulfide. 

Hunt et al. [354] used cSFC for the separation of extracts of poly(alkylene glycol) lubricants and sorbitan ester formulations. Doehl et al. [337] have compared the performance of cSFC-FID and pSFC-FID with both scC02 and scN20 in the analysis of the antiblocking agents oleamide and erucamide, the antistatic Armostat 400 and antioxidant Hostanox SE-10, none of which can be detected by UV absorption. By using open-tubular capillary columns, PAs as well as (un)substituted heavy carboxylic acids (> C ) can be eluted. 

Both PC and TEC have been used as analytical methods for QC of oleamide production from urea and oleic acid [383]. Polyamide-impregnated PC is effective in separating fatty amides of different carbon contents [384],... 

Squirrell [469] has mentioned TLC of commercial polymer additives (Topanol OC, DLTDP, DSTDP, Ionox 330, Irganox 259/288/1010/1076, Nonox WSP, Polygard, Santonox R, Tinuvin 326/327/328, Topanol CA, UV531, Hoechst D 55, oleamide, erucamide, Ethomeen T12, stearic acid, and others). A TLC procedure has also been described for identification of... 

SEC-RI/UV has also been used to analyse some 26 thioorganotin compounds, organotin carboxylates and chlorides, essentially PVC stabilisers, and some of their main by-products and related compounds (thioesters and dithioesters, n-alkanes) [803]. Not all organotin chlorides were stable in the adopted analysis conditions. N, Ai -ethylene-bis-stearamide and -oleamide in common plastics (ABS, SAN, PUR, LDPE, PA6.6) can be analysed by SEC after derivatisation with trifluo-roacetic anhydride. SEC analysis of fatty alcohol ethoxy-lates (FAE), used as nonionic surfactants, has also been described [759]. 

Figure 7.41 Microcolumn size-exclusion separation of a four-component mixture using THF as the mobile phase and UV detection at 230 nm. Legend (1) Irganox 1010 (2) oleamide (3) AO 2246 (4) Cyasorb UV9 (5) sample solvent (CHCI3). After Fujimoto et al. [931], Reprinted from Journal of Chromatography, 438, C. Fujimoto et al., 329-337, Copyright (1988), with permission from Elsevier...

Also, the usefulness of IR analysis of dissolved polymer/additive matrices is thus quite restricted. When the specific additive used is known when only qualitative results are required and when the polymer matrix is appropriate, FUR can provide a much easier, faster alternative to NMR spectroscopy. A rare example of additive analysis in dissolution by means of infrared has been reported for PE/oleamide [43]. 

Boger DL, Sato H, Lerner AE, Hedrick MP, Fesik RA, Miyauchi H, Wilkie GD, Austin BJ, Patricelli MP, Cravatt BF. Exceptionally potent inhibitors of fatty acid amide hydrolase the enzyme responsible for degradation of endogenous oleamide and anandamide. Proc Natl Acad Sci USA 2000 97 5044-5049. 

Lubricants and slip Erucamide, oleamide, calcium stearate, zinc... 

To examine slip additive concentrations in packaging films (typically 300-700 ppm), solvent extraction is used to remove the additive from the film. Hexane/ isopropanol (30/70 v/v) can be used to extract oleamide (fast bloom slip), stearamide and erucamide (slow bloom slip) from polyolefin films. GC or LC-MS is then employed to analyse the concentration of the extracted slip additive. 

Mendelson, W. B. and Basile, A. S. The hypnotic actions of the fatty acid amide, oleamide. Neuropsychopharmacology 25(5 Suppl.) S36-S39,2001... 

Slip additives act at the surface of a polymer film or article to reduce the friction between it and another surface. In a variety of plastics, such as polyolefins, polystyrene, and polyvinyl chloride, fatty-acid amides are applied as slip additives. Fatty-acid amides, such as oleamide, stearamide, erucamide, and oleyl palmitamide, are added to plastic formulations where they gradually tend to bloom to the surface, imparting useful properties including lubrication, prevention of films sticking together, and reduction of static charge. 

Within the European Union there are no restrictions regarding these additives. However, primary fatty-acid amides have been shown to have hormone-like activity, e.g., oleamide (c -9,10-octadecenoamide) is an endogenous bioregulator that acts like a sleep-inducing factor (Cravatt et al., 1995 Bezuglov et al., 1998). 

Oleamide, an unsaturated fatty acid amide, which can modulate central nervous system fiinctions, was isolated from the cerebrospinal fluid of sleep deprived cats. Nanogram amounts of oleamide in biological fluids (using GC/MS) were measured. This quantitative assay may help determine the role of oleamide in additional physiological processes. 

Its hypnotic properties were characterized. Its mechanism of action is far from being understood. Although it does not bind with high affinity to CB] or CB2 receptors, it exhibits some cannabimimetic actions, which could be explained at least in part by entourage effects. It is likely that oleamide and anandamide have common as well as distinct pathways of action. The 5-HT2A receptor appears to be a target for oleamide but the possibility of the existence of specific receptors for this compound is still open. Legget et have reported that oleamide is a full cannabi-... 

Hanus LO, Fales HM, Spande TF, Basile AS, A Gas Chromatographic-Mass Spectral Assay for the Quantitative Determination of Oleamide in Biological Y x 6, Anal Biochem 270 159—166, 1999. 

Basile AS, Hanus L, Mendelson WB, Characterization of the hypnotic properties of oleamide, NeuroReport 10 947—951, 1999. 

Lambert DM, Di Marzo V, The palmitoylethanolamide and oleamide enigmas Are these two fatty acid amides cannabimimetic Curr Med Chem 6 757-773, 1999. 

Leggett JD, Aspley S, Beckett SRG, D Antona AM, Kendall DA, Kendall DA, Oleamide is a selective endogenous agonist of rat and human CBl cannabinoid receptors, Brit JPharmacol 141 253—262, 2004. 

Hoi PM, Hiley CR, Vasorelaxant effects of oleamide in rat small mesenteric artery indicate action at a novel cannabinoid receptor, Brit J Pharmacol 147 560-568, 2006. 

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