Cannabis has been known as a medicine for several thousand years across many cultures and its beneficial effects are mostly due to the presence of cannabinoids, unique natural products, whose ...pharmacology is going to gain increasing interest in the scientific community. The discovery of the main psychoactive constituent of Cannabis sativa L., Delta^sup 9^-tetrahydrocannabinol (Delta^sup 9^-THC), led to the identification of at least 100 additional phytocannabinoids, including cannabidiol (CBD), cannabidivarin (CBDV), Delta^sup 9^-tetrahydrocannabivarin (Delta^sup 9^-THCV), and cannabigerol (CBG). These molecules are gaining growing interest for their medical properties; however, further research is needed to assess the differences in their pharmacokinetic and pharmacodymanic profiles. The aim of this study was to set up a rapid and accurate method, by using the LC-MS-IT-TOF technology, to detect and quantify CBD, CBDV, Delta^sup 9^-THCV, and CBG in biological matrices. Data show that the method developed here is linear in the calibration range; recoveries from mouse tissues were in the 50-60% range and sensitivity was 2 ng/mL for CBDV, 4 ng/mL for CBG and THCV, and 7 ng/mL for CBD. The method is rapid, precise and accurate, and it will represent a fundamental tool to evaluate the pharmacokinetic and pharmacodynamic properties of selected phytocannabinoids in tissues from different animal models, and develop new cannabinoid-based medicine.
Cis-9,10-octadecenoamide (oleamide) was isolated from the cerebrospinal fluid of sleep-deprived mammals and shown to induce sleep in rats. The enzyme catalyzing the hydrolysis of the amide bond of ...oleamide as well as of anandamide, the putative endogenous ligand of cannabinoid receptors, was purified from rat liver, cloned, shown to be expressed also in brain and named fatty acid amide hydrolase (FAAH). The enzymatic synthesis of oleamide from oleic acid and ammonia by rat brain microsomes has been also described. However, no evidence has been reported so far on the neuronal origin of oleamide, necessary in order to postulate for this compound a role as a neuromodulator. Here we show for the first time that oleamide is produced by a neuronal cell type and that its biosynthesis in intact neurons is not likely to occur through the direct condensation of oleic acid and ammonia. A lipid metabolite was extracted and purified from mouse neuroblastoma N18TG2cells through a sequence of chromatographic steps and characterized as oleamide by means of gas chromatography/electron impact mass spectrometry (GC/EIMS). The amount of oleamide, as estimated by GC analyses carried out in comparison with known amounts of synthetic oleamide, was 55.0±09.5 pmols/107cells, compared to less than 0.7 pmol/107cells for anandamide in the same cells. When N18TG2cells were prelabeled with 14Coleic acid and the lipids extracted and purified, a radioactive component with the same chromatographic behavior as oleamide was found whose levels: (1) were not significantly influenced by stimulation with ionomycin; (2) were slightly increased by incubation with FAAH inhibitor phenyl-methyl-sulphonyl-fluoride (PMSF); (3) appeared to correlate with 14Coleic acid incorporation into phospholipids but not with free 14Coleic acid levels. N18TG2cell membranes were shown to contain an enzymatic activity catalyzing the synthesis of oleamide from oleic acid and ammonia. This activity was inhibited by FAAH selective inhibitors arachidonoyltrifluoromethylketone and methylarachidonoylfluorophosphonate, as well as by an excess of anandamide, and by PMSF at the same concentration which increased oleamide formation in intact cells. These data suggest that a FAAH-like enzyme working “in reverse” may be responsible for the formation of oleamide in cell-free preparations but not in whole cells.
Cannabis has been known as a medicine for several thousand years across many cultures and its beneficial effects are mostly due to the presence of cannabinoids, unique natural products, whose ...pharmacology is going to gain increasing interest in the scientific community. The discovery of the main psychoactive constituent of Cannabis sativa L., Delta super( 9)-tetrahydrocannabinol ( Delta super( 9)-THC), led to the identification of at least 100 additional phytocannabinoids, including cannabidiol (CBD), cannabidivarin (CBDV), Delta super( 9)-tetrahydrocannabivarin ( Delta super( 9)-THCV), and cannabigerol (CBG). These molecules are gaining growing interest for their medical properties; however, further research is needed to assess the differences in their pharmacokinetic and pharmacodymanic profiles. The aim of this study was to set up a rapid and accurate method, by using the LC-MS-IT-TOF technology, to detect and quantify CBD, CBDV, Delta super( 9)-THCV, and CBG in biological matrices. Data show that the method developed here is linear in the calibration range; recoveries from mouse tissues were in the 50-60% range and sensitivity was 2 ng/mL for CBDV, 4 ng/mL for CBG and THCV, and 7 ng/mL for CBD. The method is rapid, precise and accurate, and it will represent a fundamental tool to evaluate the pharmacokinetic and pharmacodynamic properties of selected phytocannabinoids in tissues from different animal models, and develop new cannabinoid-based medicine.
The endogenous cannabimimetic substance, anandamide (
N-arachidonoyl-ethanolamine) and the recently isolated sleep-inducing factor, oleoyl-amide (
cis-9,10-octadecenoamide), belong to two neuroactive ...fatty acid amide classes whose action in mammals has been shown to be controlled by enzymatic amide bond hydrolysis. Here we report the partial characterisation and purification of ‘anandamide amidohydrolase’ from membrane fractions of N18 neuroblastoma cells, and provide evidence for a further and previously unsuspected role of this enzyme. An enzymatic activity catalysing the hydrolysis of
14Canandamide was found in both microsomal and 10,000 ×
g pellet fractions. The latter fractions, which displayed the highest
V
max for anandamide, were used for further characterisation of the enzyme, and were found to catalyse the hydrolysis also of
14Coleoyl-amide, with an apparent
K
m of 9.0 ± 2.2
μM.
14Canandamide- and
14Coleoyl-amide-hydrolysing activities: (i) exhibited identical pH- and temperature-dependency profiles; (ii) were inhibited by alkylating agents; (iii) were competitively inhibited by the phospholipase A
2 inhibitor arachidonyl-trifluoromethyl-ketone with the same IC
50 (3 μM); (iv) were competitively inhibited by both anandamide (or other polyunsaturated fatty acid-ethanolamides) and oleoyl-amide. Proteins solubilised from 10,000 ×
g pellets were directly analysed by isoelectric focusing, yielding purified fractions capable of catalysing the hydrolysis of both
14Canandamide and
14Coleoyl-amide. These data suggest that ‘anandamide amidohydrolase’ enzymes, such as that characterised in this study, may be used by neuronal cells also to hydrolyse the novel sleep-inducing factor oleoyl-amide.
Anandamide (N‐arachidonoylethanolamine) and 2‐arachidonoylglycerol are the two endogenous agonists of cannabinoid receptors discovered to date. Like other eicosanoids, and unlike classical ...neuromodulators, these two compounds are synthesized by neurons on demand, i.e., their biosynthesis, rather than release, is stimulated by Ca2+ influx and cell membrane depolarization. Both endocannabinoids can be produced from membrane phosphoglycerides through the action of phospholipases, althoughde novo pathways have also been suggested. Once released by cells, the action of both anandamide and 2‐arachidonoylglycerol is terminated—after their diffusion through the cell membrane—by the hydrolysis of the amide or ester bonds to yield arachidonic acid, which is then immediately reincorporated into phospholipids. One enzyme, fatty acid amide hydrolase, catalyzes the hydrolysis of both endocannabinoids in nervous and nonnervous cells. This enzyme also recognizesN‐palmitoylethanolamine, an antiinflammatory congener of anandamide, with a catalytic efficiency that depends on the cell type under study. However, the existence of different isozymes with different affinity for anandamide andN‐palmitoylethanolamine has not been investigated. Moreover, little work has been performed on the regulation of anandamide formation and breakdown, and several open questions remain as to the possible biosynthetic and degradative mechanisms of cannabimimetic 2‐arachidonoylglycerol in nucleated blood cells such as macrophages. Finally, the co‐existence of both endocannabinoids in invertebrates has not been fully established. Here we briefly review the state of the art, and present new data from our laboratory, on these four largely unexplored aspects of endocannabinoid metabolism.
Endocannabinoids are endogenous agonists of the mammalian cannabinoid receptors CB(1) and CB(2), and they appear to be produced in tissues as an adaptive reaction to re-establish normal homeostasis ...when this is acutely altered. However, the production of endocannabinoids can be altered pathologically. The two most widely studied endocannabinoids are anandamide and 2-arachidonoyl glycerol. The levels of these endogenous modulators are regulated in different and sometimes opposing ways, and alterations in cerebrospinal fluid and/or spinal cord levels have been documented in animal models of neurodegenerative diseases and in samples from patients with multiple sclerosis (MS). Modulation of the endocannabinoid system has been shown to have therapeutic potential in a number of disease states. Sativex(®) (nabiximols, USAN name) contains the two main phytocannabinoids from Cannabis sativa, tetrahydrocannabinol and cannabidiol in a 1:1 ratio, and it acts as an endocannabinoid system modulator. In an experimental mouse model of MS-related spasticity, Sativex dose-dependently improved hind limb flexion/stiffness and a dosage of 10 mg/kg was shown to be as effective as the most widely established anti-spasticity treatment baclofen (5 mg/kg). These findings with Sativex are very promising and offer encouragement for MS patients, the majority of whom will develop spasticity-related disabling and recalcitrant symptoms. Furthermore, research into the endocannabinoid system may offer potential in other neurodegenerative, inflammatory and pain disorders.
We synthesized new N-phenylethyl-1H-indole-2-carboxamides as the first SAR study of allosteric modulators of the CB1 receptor. The presence of the carboxamide functionality was required in order to ...obtain a stimulatory effect. The maximum stimulatory activity on CB1 was exerted by carboxamides 13 (EC50 = 50 nM) and 21 (EC50 = 90 nM) bearing a dimethylamino or piperidinyl group, respectively, at position 4 of the phenethyl moiety and a chlorine atom at position 5 of the indole.
The tissue concentrations of the endocannabinoids, 2-arachidonoylglycerol (2-AG) and
N-arachidonoyl-ethanolamine (anandamide), are altered in the adipose tissue of mice fed a high fat diet. We have ...investigated here the effect on endocannabinoid levels of incubation of mouse 3T3-F442A adipocytes with several free polyunstaurated fatty acids (PUFAs), including linolenic acid (LA), α-linolenic acid (ALA), arachidonic acid (AA) and docosahexaenoic acid (DHA), as well as oleic acid (OA) and palmitic acid (PA). By using mass spectrometric methods, we quantified the levels of endocannabinoids, of two anandamide congeners,
N-palmitoyl-ethanolamine (PEA) and
N-oleoyl-ethanolamine (OEA), and of fatty acids esterified in triacylglycerols or phospholipids, which act as 2-AG and/or
N-acyl-ethanolamine precursors. Incubation with AA strongly elevated 2-AG levels and the amounts of AA esterified in triacylglycerols and on glycerol carbon atom 2 (
sn-2), but not 1 (
sn-1), in phospholipids. Incubation with DHA decreased 2-AG and anandamide levels and the amounts of AA esterified on both the
sn-2 and
sn-1 position of phospholipids, but not on triacylglycerols. PEA levels augmented following incubation of adipocytes with OA and PA, with no corresponding changes in phospholipids and triacylglycerols. We suggest that dietary PUFAs might modulate the levels of adipocyte phospholipids that act as endocannabinoid precursors.
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