The Influence of the Cholesterol Level in Cells on Endovanilloid Cytotoxicity.

The influence of the cellular cholesterol content on the cytotoxicity of endovanilloids acyldopamines was studied in MDA-MB-231 and MCF 10A cells. The activity of acyldopamines depends on the cellular cholesterol content, and a decrease in cholesterol content increases the cytotoxicity of acyldopamines.

Neuroprotective and Antioxidant Activity of Arachidonoyl Choline, Its Bis-Quaternized Analogues and Other Acylcholines.

The antioxidant activity and protective effect in the toxicity model of H2O2 were studied for arachidonic (AA-CHOL), docosahexaenoic (DHA-CHOL), linoleic (Ln-CHOL), and oleic (Ol-CHOL) fatty acids, as well as arachidonoyl dicholine (AA-diCHOL) and O-arachidonoyl bistetramethylaminoisopropanol (ABTAP). AA-CHOL, DHA-CHOL and Ln-CHOL provided a 20% increase in cell survival. AA-CHOL, AA-diCHOL, Ol-CHOL, and ABTAP had a radical-scavenging effect in the ABTS test, approximately equal to the activity of a standard radical scavenger Trolox.

Selective Action of N-Arachidonoyl Dopamine on Viability and Proliferation of Stromal Cells from Eutopic and Ectopic Endometrium.

We performed a comparative study of the cytotoxic effect of endocannabinoid N-arachidonoyl dopamine (AA-DA) on cultured stromal cells of ectopic and eutopic endometrium. It was found that AA-DA in the concentration range of 1-20 µM produces more selective cytotoxic effect on the stromal cells of the ectopic endometrium due to interaction with cannabinoid type 1 receptor. In concentrations below 1 µM, AA-DA stimulated the proliferation of stromal cells of the eutopic endometrium and did not affect the division of ectopic endometrium cells. This effect was realized due to its interaction with cannabinoid type 2 receptor.

Neuroprotective Action of Amidic Neurolipins in Models of Neurotoxicity on the Culture of Human Neural-Like Cells SH-SY5Y.

It was established that in neurodegeneration models in the human neuron-like cell line SH-SY5Y, amide derivatives of arachidonic and docosahexaenoic acids were inactive in experiments with MPP+ and CoCl2 but protected from H2O2. The protective activity of neurolipins decreased in the series DHA-DA > AA-SER ≥ AA-GLY > AA-GABA ≥ AA-EA and was manifested starting from a concentration of 0.5 nM.

N-acyl dopamines induce apoptosis in PC12 cell line via the GPR55 receptor activation.

Dopamine amides of arachidonic, docosahexaenoic, and oleic acids were found to induce apoptosis in PC12 cells, which was blocked exclusively by antagonists and preincubation agonists of the receptor GPR55, belonging to the group of non-CB1/CB2 receptors.

N-acyl dopamines induce cell death in PC12 cell line via induction of nitric oxide generation and oxidative stress.

It was shown that dopamine amides of arachidonic, oleic, and docosahexaenoic acids exhibit toxicity with respect to PC12 pheochromocytoma cell line. The mechanism of realization of the cytotoxic effect of acyl dopamines is the induction of oxidative stress. This event is preceded by triggering the synthesis of nitric oxide.

Binding assessment of two arachidonic-based synthetic derivatives of adrenalin with ß-lactoglobulin: Molecular modeling and chemometrics approach.

A computational approach to predict the main binding modes of two adrenalin derivatives, arachidonoyl adrenalin (AA-AD) and arachidonoyl noradrenalin (AA-NOR) with the ß-lactoglubuline (BLG) as a nano-milk protein carrier is presented and assessed by comparison to the UV-Vis absorption spectroscopic data using chemometric analysis. Analysis of the spectral data matrices by using the multivariate curve resolution-alternating least squares (MCR-ALS) algorithm led to the pure concentration calculation and spectral profiles resolution of the chemical constituents and the apparent equilibrium constants computation. The negative values of entropy and enthalpy changes for both compound indicated the essential role of hydrogen bonding and van der Waals interactions as main driving forces in stabilizing protein-ligand complex. Computational studies predicted that both derivatives are situated in the calyx pose and remained in that pose during the whole time of simulation with no any significant protein structural changes which pointed that the BLG could be considered as a suitable carrier for these catecholamine compounds.

[STUDYING NEUROPROTECTIVE ACTIVITY OF GABA CONJUGATE WITH ARACHIDONIC ACID UNDER CONDITIONS OF LOCAL PERMANENT BRAIN ISCHEMIA IN RATS].

We have studied the effect of a GABA conjugate with arachidonic acid (AA) on the morphological state of rat brain tissues after left median cerebral artery occlusion. The results showed that a 6- and 12-day course administration of the GABA - AA conjugate at dose of 2 mg/kg (i.p.) in rats with this model of local permanent brain ischemia led to significant recovery processes in brain tissues. The tissue morphology pattern in the group of animals treated with the GABSA - AA conjugate for 12 days was almost identical to that in intact tissues.

In vitro effects of anandamide and prostamide e2 on normal and transformed nerve cells.

We studied the effects of endocannabinoid anandamide and its cyclooxygenase derivative prostamide E2 on cultured cerebellar granular cells and C6 glioma cells from rats. Prostamide E2 prevented apoptosis in cerebellar neurons induced by potassium deprivation of cultures, while anandamide had no neuroprotective properties. Prostamide E2 did not modulate the survival rate of glioma cells, while anandamide produced a cytotoxic effect. Our results indicate that cyclooxygenase transformation of anandamide is followed by the loss of antitumor activity of this agent. By contrast, prostamide E2 exhibited strong neuroprotective properties.

Sulfation of N-acyl dopamines in rat tissues.

Sulfation of N-acyl dopamines has been shown for the first time in cytosolic fractions of rat liver and nervous system. Sulfation of dopamine amides of docosahexaenoic and oleic acids occurred in all tissues studied, N-arachidonoyl dopamine was sulfated in the liver and spinal cord, and N-stearoyl dopamine was sulfated only in the liver. Depending on the substrate and tissue, the sulfation activity varied from 0.5 to 3.5 nmol/min per mg total protein. Kinetic parameters of N-docosahexaenoyl dopamine sulfation in the brain were determined. The findings characterize the sulfation system as the most productive metabolic pathway of N-acyl dopamines, but the role of this system in the body is unclear because of high K(m) value.

[Nanocomplexes of recombinant proteins and polysialic acid: preparation, characteristics, and biological activity].

A preparation of nanocomplexes containing recombinant proteins (interferons alpha2b and beta1b, insulin, and human granulocyte colony stimulating factor) and natural polysialic acid (PSA) has been described. The incorporation of protein into the complex changes its electrophoretic mobility. Atomic force microscopy reveals the average size of 23-kD insulin complexes with PSA of 10-20 nm and demonstrates that more than 60% of glycopolymer molecules carry a single protein molecule. Experiments with cultured cells show that cytokines bound to polysialic acid retain their ability to regulate cell proliferation. Insulin bound to PSA has a prolonged hypoglycemic effect in vivo.

Antioxidant and neuroprotective properties of N-docosahexaenoyl dopamine.

N-Docosahexaenoyl dopamine exhibited antioxidant activity in the test with a stable oxygen radical galvinoxyl. This compound produced a dose-dependent protective effect on cultured granular cells from rat cerebellum under conditions of oxidative stress. N-Docosahexaenoyl dopamine decelerated the development of symptoms of Parkinson's disease in mice receiving neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine.

N-acyl-dopamines: novel synthetic CB(1) cannabinoid-receptor ligands and inhibitors of anandamide inactivation with cannabimimetic activity in vitro and in vivo.

We reported previously that synthetic amides of polyunsaturated fatty acids with bioactive amines can result in substances that interact with proteins of the endogenous cannabinoid system (ECS). Here we synthesized a series of N-acyl-dopamines (NADAs) and studied their effects on the anandamide membrane transporter, the anandamide amidohydrolase (fatty acid amide hydrolase, FAAH) and the two cannabinoid receptor subtypes, CB(1) and CB(2). NADAs competitively inhibited FAAH from N18TG2 cells (IC(50)=19-100 microM), as well as the binding of the selective CB(1) receptor ligand, [(3)H]SR141716A, to rat brain membranes (K(i)=250-3900 nM). The arachidonoyl (20:4 omega 6), eicosapentaenoyl (20:5 omega 3), docosapentaenoyl (22:5 omega 3), alpha-linolenoyl (18:3 omega 3) and pinolenoyl (5c,9c,12c 18:3 omega 6) homologues were also found to inhibit the anandamide membrane transporter in RBL-2H3 basophilic leukaemia and C6 glioma cells (IC(50)=17.5-33 microM). NADAs did not inhibit the binding of the CB(1)/CB(2) receptor ligand, [(3)H]WIN55,212-2, to rat spleen membranes (K(i)>10 microM). N-arachidonyl-dopamine (AA-DA) exhibited 40-fold selectivity for CB(1) (K(i)=250 nM) over CB(2) receptors, and N-docosapentaenoyl-dopamine exhibited 4-fold selectivity for the anandamide transporter over FAAH. AA-DA (0.1-10 microM) did not displace D1 and D2 dopamine-receptor high-affinity ligands from rat brain membranes, thus suggesting that this compound has little affinity for these receptors. AA-DA was more potent and efficacious than anandamide as a CB(1) agonist, as assessed by measuring the stimulatory effect on intracellular Ca(2+) mobilization in undifferentiated N18TG2 neuroblastoma cells. This effect of AA-DA was counteracted by the CB(1) antagonist SR141716A. AA-DA behaved as a CB(1) agonist in vivo by inducing hypothermia, hypo-locomotion, catalepsy and analgesia in mice (1-10 mg/kg). Finally, AA-DA potently inhibited (IC(50)=0.25 microM) the proliferation of human breast MCF-7 cancer cells, thus behaving like other CB(1) agonists. Also this effect was counteracted by SR141716A but not by the D2 antagonist haloperidol. We conclude that NADAs, and AA-DA in particular, may be novel and useful probes for the study of the ECS.

Hydrolysis of anandamide and eicosapentaenoic acid ethanolamide in mouse splenocytes.

The hydrolysis of anandamide has been studied in mouse splenocytes using tritiated anandamide analogs labeled in the acyl- or ethanolamide parts of the molecule. [3H]Anandamide undergoes rapid (t(1/2) = 2.5 min) uptake and hydrolysis, yielding ethanolamine and arachidonic acid. The anandamide hydrolysis in splenocytes is sensitive to inhibition by phenylmethylsulfonyl fluoride, and it is assumed that the observed activity is due to fatty acid amide hydrolase, which inactivates anandamide in central and peripheral tissues. Eicosapentaenoic acid ethanolamide and the 15-hydroxy-derivative of anandamide are shown to be amidohydrolase substrates as well. The fatty acids derived from hydrolytic cleavage of acylethanolamines undergo rapid oxidation by splenocyte lipoxygenase, yielding the corresponding 12-hydroxy-derivatives. Oxygenated ethanolamide derivatives were not found. The data suggest that polyenoic fatty acid ethanolamides are metabolic precursors of eicosanoids in splenocytes and that amide bond hydrolysis is the key point in switching of biological activity spectra between endocannabinoids and oxylipins.

Arachidonoylserotonin and other novel inhibitors of fatty acid amide hydrolase.

Fatty acid amide hydrolase (FAAH) catalyzes the hydrolysis of bioactive fatty acid amides and esters such as the endogenous cannabinoid receptor ligands, anandamide (N-arachidonoyl-ethanolamine) and 2-arachidonoylglycerol, and the putative sleep inducing factor cis-9-octadecenoamide (oleamide). Most FAAH blockers developed to date also inhibit cytosolic phospholipase A2 (cPLA2) and/or bind to the CB1 cannabinoid receptor subtype. Here we report the finding of four novel FAAH inhibitors, two of which, malhamensilipin A and grenadadiene, were screened out of a series of thirty-two different algal natural products, and two others, arachidonoylethylene glycol (AEG) and arachidonoyl-serotonin (AA-5-HT) were selected out of five artificially functionalized polyunsaturated fatty acids. When using FAAH preparations from mouse neuroblastoma N18TG2 cells and [14C]anandamide as a substrate, the IC50s for these compounds ranged from 12.0 to 26 microM, the most active compound being AA-5-HT. This substance was also active on FAAH from rat basophilic leukaemia (RBL-2H3) cells (IC50 = 5.6 microM), and inhibited [14C]anandamide hydrolysis by both N18TG2 and RBL-2H3 intact cells without affecting [14C]anandamide uptake. While AEG behaved as a competitive inhibitor and was hydrolyzed to arachidonic acid (AA) by FAAH preparations, AA-5-HT was resistant to FAAH-catalyzed hydrolysis and behaved as a tight-binding, albeit non-covalent, mixed inhibitor. AA-5-HT did not interfere with cPLA2-mediated, ionomycin or antigen-induced release of [3H]AA from RBL-2H3 cells, nor with cPLA2 activity in cell-free experiments. Finally, AA-5-HT did not activate CB1 cannabinoid receptors since it acted as a very weak ligand in in vitro binding assays, and, at 10-15 mg/kg body weight, it was not active in the 'open field', 'hot plate' and rectal hypothermia tests carried out in mice. Conversely AEG behaved as a cannabimimetic substance in these tests as well as in the 'ring' immobility test where AA-5-HT was also active. AA-5-HT is the first FAAH inhibitor reported to date which is inactive both against cPLA2 and at CB1 receptors, whereas AEG represents a new type of cannabinoid receptor agonist.