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Endocannabinoid anandamide (AEA) and paracannabinoid lysophosphatidylinositol (LPI) play a significant role in cancer cell proliferation regulation. While anandamide inhibits the proliferation of cancer cells, LPI is known as a cancer stimulant. Despite the known endocannabinoid receptor crosstalk and simultaneous presence in the cancer microenvironment of both molecules, their combined activity has never been studied. We evaluated the effect of LPI on the AEA activity in six human breast cancer cell lines of different carcinogenicity (MCF-10A, MCF-7, BT-474, BT-20, SK-BR-3, MDA-MB-231) using resazurin and LDH tests after a 72 h incubation. AEA exerted both anti-proliferative and cytotoxic activity with EC50 in the range from 31 to 80 µM. LPI did not significantly affect the cell viability. Depending on the cell line, the response to the LPI–AEA combination varied from a decrease in AEA cytotoxicity to an increase in it. Based on the inhibitor analysis of the endocannabinoid receptor panel, we showed that for the former effect, an active GPR18 receptor was required and for the latter, an active CB2 receptor. The data obtained for the first time are important for the understanding the manner by which endocannabinoid receptor ligands acting simultaneously can modulate cancer growth at different stages. [ABSTRACT FROM AUTHOR]

Despite the wide variety of available cationic lipid platforms for the delivery of nucleic acids into cells, the optimization of their composition has not lost its relevance. The purpose of this work was to develop multi-component cationic lipid nanoparticles (LNPs) with or without a hydrophobic core from natural lipids in order to evaluate the efficiency of LNPs with the widely used cationic lipoid DOTAP (1,2-dioleoyloxy-3-[trimethylammonium]-propane) and the previously unstudied oleoylcholine (Ol-Ch), as well as the ability of LNPs containing GM3 gangliosides to transfect cells with mRNA and siRNA. LNPs containing cationic lipids, phospholipids and cholesterol, and surfactants were prepared according to a three-stage procedure. The average size of the resulting LNPs was 176 nm (PDI 0.18). LNPs with DOTAP mesylate were more effective than those with Ol-Ch. Core LNPs demonstrated low transfection activity compared with bilayer LNPs. The type of phospholipid in LNPs was significant for the transfection of MDA-MB-231 and SW 620 cancer cells but not HEK 293T cells. LNPs with GM3 gangliosides were the most efficient for the delivery of mRNA to MDA-MB-231 cells and siRNA to SW620 cells. Thus, we developed a new lipid platform for the efficient delivery of RNA of various sizes to mammalian cells. [ABSTRACT FROM AUTHOR]

GPR55 is a non-canonical cannabinoid receptor, important for cancer proliferation. Depending on the ligand, it induces either cell proliferation or death. The objective of the study was to establish the mechanisms of this multidirectional signaling. Using the CRISPR-Cas9 system, the GPR55, CB1, CB2, and GPR18 receptor knockouts of the MDA-MB-231 line were obtained. After the CB2 receptor knockout, the pro-apoptotic activity of the pro-apoptotic ligand docosahexaenoyl dopamine (DHA-DA) slightly increased, while the pro-proliferative activity of the most active synthetic ligand of the GPR55 receptor (ML-184) completely disappeared. On the original cell line, the stimulatory effect of ML-184 was removed by the CB2 receptor blocker and by GPR55 receptor knockout. Thus, it can be confidently assumed that when proliferation is stimulated with the participation of the GPR55 receptor, a signal is transmitted from the CB2 receptor to the GPR55 receptor due to the formation of a heterodimer. GPR18 was additionally involved in the implementation of the pro-apoptotic effect of DHA-DA, while the CB1 receptor is not involved. In the implementation of the pro-apoptotic action of DHA-DA, the elimination of Gα13 led to a decrease in cytotoxicity. The obtained data provide novel details to the mechanism of the pro-proliferative action of GPR55. [ABSTRACT FROM AUTHOR]

This is the first study aiming to develop a method for the long-term visualization of living nigrostriatal dopaminergic neurons using 1-(2-(bis(4-fluorophenyl)methoxy)ethyl)-4-(3-phenylpropyl)piperazine-BODIPY (GBR-BP), the original fluorescent substance, which is a derivative of GBR-12909, a dopamine uptake inhibitor. This method is based on the authors' hypothesis about the possibility of specifically internalizing into dopaminergic neurons substances with a high affinity for the dopamine transporter (DAT). Using a culture of mouse embryonic mesencephalic and LUHMES cells (human embryonic mesencephalic cells), as well as slices of the substantia nigra of adult mice, we have obtained evidence that GBR-BP is internalized specifically into dopaminergic neurons in association with DAT via a clathrin-dependent mechanism. Moreover, GBR-BP has been proven to be nontoxic. As we have shown in a primary culture of mouse metencephalon, GBR-BP is also specifically internalized into some noradrenergic and serotonergic neurons, but is not delivered to nonmonoaminergic neurons. Our data hold great promise for visualization of dopaminergic neurons in a mixed cell population to study their functioning, and can also be considered a new approach for the development of targeted drug delivery to dopaminergic neurons in pathology, including Parkinson's disease. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the study was to compare the neuroprotective and cerebrovascular effects of bioactive, endogenous lipid -- N-arachidonoyl-GABA (AA-GABA) and GABA conjugate with prostaglandin E2 (PGE2-GABA) by evaluation of a morphological state of rat brain tissue and lipofuscin levels under the condition of permanent focal brain ischemia, as well as cerebral circulation under the condition of global transient ischemia. Materials and methods: The study has been implemented using the models of the left middle cerebral artery occlusion (MCAO) and global transient ischemia of the brain. A morphological examination of the brain tissue, a registration of local blood flow by laser flowmeter, and quantitative measurement of lipofuscin by fluorescence spectroscopy were used. Results and discussion: AA-GABA and the putative COX-2 metabolite PGE2-GABA showed significant neuroprotective and cerebrovascular effects in rat models of global and focal cerebral ischemia. In the MCAO model, AA-GABA and PGE2-GABA at a dose of 2 mg/kg/day administered i.p. for 6 or 12 days led to: 1) significant restoration of neurons and glial cells with intracellular regeneration of cytoplasmic and nuclear structures, 2) decrease in brain tissue edema; 3) attenuated thrombosis and stasis, and 4) absence of large necrotic foci in rat brain tissue. AA-GABA and PGE2-GABA at the same dose prevented excessive accumulation of lipofuscin in both brain hemispheres in rats with MCAO. All the studied compounds increase cerebral blood circulation in rats subjected to global transient ischemia. However, the cerebrovascular effect of PGE2-GABA was superior to the activity of AA-GABA and all other tested compounds. AA-GABA and PGE2-GABA, unlike PGE2 and nimodipine, increase the cerebral blood flow in rats with global transient brain ischemia and have no influence on the intact animals. Apparently, the GABAergic vascular system of the brain is involved in the mechanisms of the neuroprotective action of AA-GABA and PGE2-GABA. Conclusion: For the first time, we demonstrated the ability of AA-GABA and its putative metabolite COX-2 PGE2-GABA to improve cerebral circulation, attenuate structural damage and lipofuscin accumulation during cerebral ischemia. The natural origin of AA-GABA, which possesses neuroprotective and cerebrovascular activity, as well as anti-aggregatory activity, allows considering AA-GABA as one of the endogenous protective factors in ischemic brain lesions. [ABSTRACT FROM AUTHOR]

N‐acyl dopamines (NADAs) are bioactive lipids of the endovanilloid family with known cytotoxicity for the cancer cells; however, the available data on the participation of the endovanilloids in epithelial–mesenchymal transition (EMT) and cancer stemness are controversial. This study unveils the inhibitory role of N‐arachidonoyl dopamine (AA‐DA), a typical representative of the NADA family, in breast cancer cell migration, EMT, and stemness. AA‐DA treatment also led to a decrease in cholesterol biosynthesis gene expressions, and addition of exogenous cholesterol reverted these AA‐DA‐mediated inhibitory effects. Notably, AA‐DA treatment inhibited the key regulatory gene of the cholesterol biosynthesis pathway, sterol regulatory element‑binding protein 1 (SREBP1), with concurrent repression of the endoplasmic reticulum kinase 1/2 (ERK1/2) pathway. Furthermore, U0126, an ERK inhibitor, inhibited SREBP1 and decreased cellular cholesterol level, unwinding the molecular mechanism behind AA‐DA‐mediated anticancer activity. Thus, we, for the first time, revealed that AA‐DA counteracts breast cancer EMT via inhibition of ERK signaling and cholesterol content. [ABSTRACT FROM AUTHOR]

β-Lactoglobulin (β-LG) is a lipocalin, which is the major whey protein of cow's milk and the milk of other mammals. However, it is absent from human milk. The biological function of β-LG is not clear, but its potential role in carrying fatty acids through the digestive tract has been suggested. β-LG has been found in complexes with lipids such as butyric and oleic acids and has a high affinity for a wide variety of compounds. Serotonin (5-hydroxytryptamine, 5-HT), an important compound found in animals and plants, has various functions, including the regulation of mood, appetite, sleep, muscle contraction, and some cognitive functions such as memory and learning. In this study, the interaction of serotonin and one of its derivatives, arachidonyl serotonin (AA-5HT), with β-LG was investigated using circular dichroism (CD) and fluorescence intensity measurements. These two ligands interact with β-LG forming equimolar complexes. The binding constant for the serotonin/β-LG interaction is between 105 and 106 M−1, whereas for the AA-5HT/β-LG complex it is between 104 and 105 M−1 as determined by measurements of either protein or ligand fluorescence. The observed binding affinities were higher in hydroethanolic media (25% EtOH). The interactions between serotonin/β-LG and AA-5HT/β-LG may compete with self-association (micellization) of both the ligand and the protein. According to far- and near-UV CD results, these ligands have no apparent influence on β-LG secondary structure, however they partially destabilize its tertiary structure. Their binding by β-LG may be one of the peripheral mechanisms of the regulation of the content of serotonin and its derivatives in the bowel of milk-fed animals. © 2011 Wiley Periodicals, Inc. Biopolymers 95: 871-880, 2011. [ABSTRACT FROM AUTHOR]

Endometriosis is characterized by the formation and development of endometrial tissues outside the uterus, based on an imbalance between proliferation and cell death, leading to the uncontrolled growth of ectopic foci. The potential target for the regulation of these processes is the endocannabinoid system, which was found to be involved in the migration, proliferation, and survival of tumor cells. In this paper, we investigated the effect of endocannabinoid-like compounds from the N-acyl dopamine (NADA) family on the viability of stromal cells from ectopic and eutopic endometrium of patients with ovarian endometriosis. N-arachidonoyldopamine, N-docosahexaenoyldopamine, and N-oleoyldopamine have been shown to have a five-times-more-selective cytotoxic effect on endometrioid stromal cells. To study the mechanisms of the toxic effect, inhibitory analysis, measurements of caspase-3/9 activity, reactive oxygen species, and the mitochondrial membrane potential were performed. It was found that NADA induced apoptosis via an intrinsic pathway through the CB1 receptor and downstream serine palmitoyltransferase, NO synthase activation, increased ROS production, and mitochondrial dysfunction. The higher selectivity of NADA for endometriotic stromal cells and the current lack of effective drug treatment can be considered positive factors for further research of these compounds as possible therapeutic agents against endometriosis. [ABSTRACT FROM AUTHOR]

Stabilized melanocortin analog peptide ACTH(6–9)PGP (HFRWPGP) possesses a wide range of neuroprotective activities. However, its mechanism of action remains poorly understood. In this paper, we present a study of the proproliferative and cytoprotective activity of the adrenocorticotropic hormone fragment 6–9 (HFRW) linked with the peptide prolyine–glycyl–proline on the SH-SY5Y cells in the model of oxidative stress-related toxicity. The peptide dose-dependently protected cells from H2O2, tert-butyl hydroperoxide, and KCN and demonstrated proproliferative activity. The mechanism of its action was the modulation of proliferation-related NF-κB genes and stimulation of prosurvival NRF2-gene-related pathway, as well as a decrease in apoptosis. [ABSTRACT FROM AUTHOR]

GPR55 is a GPCR of the non-CB1/CB2 cannabinoid receptor family, which is activated by lysophosphatidylinositol (LPI) and stimulates the proliferation of cancer cells. Anandamide, a bioactive lipid endocannabinoid, acts as a biased agonist of GPR55 and induces cancer cell death, but is unstable and psychoactive. We hypothesized that other endocannabinoids and structurally similar compounds, which are more hydrolytically stable, could also induce cancer cell death via GPR55 activation. We chemically synthesized and tested a set of fatty acid amides and esters for cell death induction via GPR55 activation. The most active compounds appeared to be N-acyl dopamines, especially N-docosahexaenoyl dopamine (DHA-DA). Using a panel of cancer cell lines and a set of receptor and intracellular signal transduction machinery inhibitors together with cell viability, Ca2+, NO, ROS (reactive oxygen species) and gene expression measurement, we showed for the first time that for these compounds, the mechanism of cell death induction differed from that published for anandamide and included neuronal nitric oxide synthase (nNOS) overstimulation with concomitant oxidative stress induction. The combination of DHA-DA with LPI, which normally stimulates cancer proliferation and is increased in cancer setting, had an increased cytotoxicity for the cancer cells indicating a therapeutic potential. [ABSTRACT FROM AUTHOR]

Prostanit is a novel drug developed for the treatment of peripheral arterial diseases. It consists of a prostaglandin E1 (PGE1) moiety with two nitric oxide (NO) donor fragments, which provide a combined vasodilation effect on smooth muscles and vascular spastic reaction. Prostanit pharmacokinetics, however, remains poorly investigated. Thus, the object of this study was to investigate the pharmacokinetics of Prostanit-related and -affected metabolites in rabbit plasma using the liquid chromatography-mass spectrometry (LC-MS) approach. Besides, NO generation from Prostanit in isolated rat aorta and human smooth muscle cells was studied using the Griess method. In plasma, Prostanit was rapidly metabolized to 1,3-dinitroglycerol (1,3-DNG), PGE1, and 13,14-dihydro-15-keto-PGE1. Simultaneously, the constant growth of amino acid (proline, 4-hydroxyproline, alanine, phenylalanine, etc.), steroid (androsterone and corticosterone), and purine (adenosine, adenosine-5 monophosphate, and guanosine) levels was observed. Glycine, aspartate, cortisol, and testosterone levels were decreased. Ex vivo Prostanit induced both NO synthase-dependent and -independent NO generation. The observed pharmacokinetic properties suggested some novel beneficial activities (i.e., effect prolongation and anti-inflammation). These properties may provide a basis for future research of the effectiveness and safety of Prostanit, as well as for its characterization from a clinical perspective. [ABSTRACT FROM AUTHOR]

Cholines acylated with unsaturated fatty acids are a recently discovered family of endogenous lipids. However, the data on the biological activity of acylcholines remain very limited. We hypothesized that acylcholines containing residues of arachidonic (AA-CHOL), oleic (Ol-CHOL), linoleic (Ln-CHOL), and docosahexaenoic (DHA-CHOL) acids act as modulators of the acetylcholine signaling system. In the radioligand binding assay, acylcholines showed inhibition in the micromolar range of both α7 neuronal nAChR overexpressed in GH4C1 cells and muscle type nAChR from Torpedo californica, as well as Lymnaeastagnalis acetylcholine binding protein. Functional response was checked in two cell lines endogenously expressing α7 nAChR. In SH-SY5Y cells, these compounds did not induce Ca2+ rise, but inhibited the acetylcholine-evoked Ca2+ rise with IC50 9 to 12 μM. In the A549 lung cancer cells, where α7 nAChR activation stimulates proliferation, Ol-CHOL, Ln-CHOL, and AA-CHOL dose-dependently decreased cell viability by up to 45%. AA-CHOL inhibited human erythrocyte acetylcholinesterase (AChE) and horse serum butyrylcholinesterase (BChE) by a mixed type mechanism with Ki= 16.7 ± 1.5 μM and αKi= 51.4 ± 4.1 μM for AChE and Ki= 70.5 ± 6.3 μM and αKi= 214 ± 17 μM for BChE, being a weak substrate of the last enzyme only, agrees with molecular docking results. Thus, long-chain unsaturated acylcholines could be viewed as endogenous modulators of the acetylcholine signaling system. [ABSTRACT FROM AUTHOR]

Abstract: Accumulation of β-amyloid protein is an Alzheimer''s disease hallmark but also may be mechanistically involved in neurodegeneration. One of its cleavage peptides, Aβ42, has been used to evaluate the mechanisms underlying amyloid-induced cytotoxicity and targeting of acetylcholine systems. We studied Sphaerechinus granularis sea urchin embryos which utilize acetylcholine and other neurotransmitters as morphogens. At a threshold concentration of 0.1μM Aβ42, there was damage to the larval skeleton, accumulation of ectodermal cells in the blastocoele and underdevelopment of larval arms. Raising the Aβ42 concentration to 0.2–0.4μM produced anomalies depending on the stage at which Aβ42 was introduced: at the first cleavage divisions, abnormalities appeared within 1–2 cell cycles; at the mid-blastula stage, the peak period of sensitivity to Aβ42, gastrulation was blocked; at later stages, there was progressive damage to the larval skeleton, digestive tract and larval spicules, as well as regression of larval arms. Each of these anomalies could be offset by the addition of lipid-permeable analogs of acetylcholine (arachidonoyl dimethylaminoethanol), serotonin (arachidonoyl serotonin) and cannabinoids (arachidonoyl vanillylamine), with the greatest activity exhibited by the acetylcholine analog. These results indicate that sea urchin embryos provide a model suitable to characterize the mechanisms underlying the cytotoxicity of Aβ42, as well as providing a system that enables the rapid screening of potential therapeutic interventions. The protection provided by neurotransmitter analogs, especially that for acetylcholine, points to unsuspected advantages of existing therapies that enhance cholinergic function, as well as indicating novel approaches that may prove protective in Alzheimer''s disease. [Copyright &y& Elsevier]

Abstract: Amyloid precursor protein (APP) is overexpressed in the developing brain and portions of its extracellular domain, especially amino acid residues 96–110, play an important role in neurite outgrowth and neural cell differentiation. In the current study, we evaluated the developmental abnormalities caused by administration of exogenous APP96–110 in sea urchin embryos and larvae, which, like the developing mammalian brain, utilize acetylcholine and other neurotransmitters as morphogens; effects were compared to those of β-amyloid 1–42 (Aβ42), the neurotoxic APP fragment contained within neurodegenerative plaques in Alzheimer''s Disease. Although both peptides elicited dysmorphogenesis, Aβ42 was far more potent; in addition, whereas Aβ42 produced abnormalities at developmental stages ranging from early cleavage divisions to the late pluteus, APP96–110 effects were restricted to the intermediate, mid-blastula stage. For both agents, anomalies were prevented or reduced by addition of lipid-permeable analogs of acetylcholine, serotonin or cannabinoids; physostigmine, a carbamate-derived cholinesterase inhibitor, was also effective. In contrast, agents that act on NMDA receptors (memantine) or α-adrenergic receptors (nicergoline), and that are therapeutic in Alzheimer''s Disease, were themselves embryotoxic, as was tacrine, a cholinesterase inhibitor from a different chemical class than physostigmine. Protection was also provided by agents acting downstream from receptor-mediated events: increasing cyclic AMP with caffeine or isobutylmethylxanthine, or administering the antioxidant, a-tocopherol, were all partially effective. Our findings reinforce a role for APP in development and point to specific interactions with neurotransmitter systems that act as morphogens in developing sea urchins as well as in the mammalian brain. [Copyright &y& Elsevier]

Abstract: N-Acyldopamines were recently described as putative endogenous substances in the rat brain. Among them, N-arachidonoyldopamine (AADA) was characterized as cannabinoid CB1 and vanilloid TRPV1 receptor ligand. The physiological significance of such compounds is yet poorly understood. In this study, we describe the novel properties of AADA as antioxidant and neuroprotectant. Antioxidant potential of AADA and its analogs were first tested in the galvinoxyl assay. It was found that N-acyldopamines are potent antioxidants and that the number of free hydroxyl groups in the phenolic moiety of dopamine is essential for the activity. AADA dose dependently (0.1–10μM) protected cultured cerebellar granule neurons (CGN) in the model of oxidative stress induced by hydrogen peroxide. N-Oleoyldopamine, another endogenous substance, was much less potent in these conditions while the natural antioxidant α-tocopherol was inactive. In this test, AADA decreased the peroxide level in CGN preparations and its neuroprotection was independent of cannabinoid/vanilloid receptors blockade. AADA (10μM) also protected CGN from death induced by K+/serum deprivation and glutamate exitotoxicity. These data indicate that AADA may act as endogenous antioxidant in different pathological conditions. [Copyright &y& Elsevier]

Abstract: Lower organisms show promise for the screening of neurotoxicants that might target mammalian brain development. Sea urchins use neurotransmitters as embryonic growth regulatory signals, so that adverse effects on neural substrates for mammalian brain development can be studied in this simple organism. We compared the effects of the organophosphate insecticide, chlorpyrifos in sea urchin embryos with those of the monoamine depleter, reserpine, so as to investigate multiple neurotransmitter mechanisms involved in developmental toxicity and to evaluate different therapeutic interventions corresponding to each neurotransmitter system. Whereas reserpine interfered with all stages of embryonic development, the effects of chlorpyrifos did not emerge until the mid-blastula stage. After that point, the effects of the two agents were similar. Treatment with membrane permeable analogs of the monoamine neurotransmitters, serotonin and dopamine, prevented the adverse effects of either chlorpyrifos or reserpine, despite the fact that chlorpyrifos works simultaneously through actions on acetylcholine, monoamines and other neurotransmitter pathways. This suggests that different neurotransmitters, converging on the same downstream signaling events, could work together or in parallel to offset the developmental disruption caused by exposure to disparate agents. We tested this hypothesis by evaluating membrane permeable analogs of acetylcholine and cannabinoids, both of which proved effective against chlorpyrifos- or reserpine-induced teratogenesis. Invertebrate test systems can provide both a screening procedure for mammalian neuroteratogenesis and may uncover novel mechanisms underlying developmental vulnerability as well as possible therapeutic approaches to prevent teratogenesis. [Copyright &y& Elsevier]

Glioblastoma (GBM) is an aggressive and lethal form of brain cancer with a high invasion capacity and a lack of effective chemotherapeutics. Retinoid bexarotene (BXR) inhibits the neurospheroidal colony formation and migration of primary glioblastoma cells but has side effects. To enhance the BXR glioblastoma selectivity and cytotoxicity, we chemically modified it at the carboxyl group with either nitroethanolamine (NEA) bearing a NO-donating group (a well-known bioactivity enhancer; BXR-NEA) or with a dopamine (DA) moiety (to represent the highly toxic for various tumor cells N-acyldopamine family; BXR-DA). These two novel compounds were tested in the 2D (monolayer culture) and 3D (multicellular tumor spheroids) in vitro models. Both BXR-DA and BXR-NEA were found to be more toxic for rat C6 and human U-87MG glioma cells than the initial BXR. After 24 h incubation of the cells (monolayer culture) with the drugs, the IC 50 values were in the range of 28–42, and 122–152 μM for BXR derivatives and BXR, respectively. The cell death occurred via apoptosis according to the annexin staining and caspase activation. The tumor spheroids demonstrated higher resistance to the treatment compared to that one of the monolayer cultures. BXR-DA and BXR-NEA were more specific against tumor cells than the parental drug, in particular the selectivity index was 1.8–2.7 vs. 1.3–1.5, respectively. Moreover, they inhibited cell migration more effectively than parental BXR according to a scratch assay. Cell spreading from the tumor spheroids was also inhibited. Thus, the obtained BXR derivatives could be promising for glioblastoma treatment. Image 1 [ABSTRACT FROM AUTHOR]

Oxidative stress (OS) is implicated in the pathogenesis of several neurodegenerative diseases. We have previously shown that N-acyl dopamines (N-ADA and N-DDA) protect the neural cells of healthy donors and patients with Parkinson's disease from OS. In this study, we assessed the effects of N-acyl dopamines on the expression of neurotrophic factors in human-induced pluripotent stem cell-derived neuronal cultures enriched with dopaminergic neurons under conditions of OS induced by hydrogen peroxide. We showed that hydrogen peroxide treatment increased BDNF but not GDNF mRNA levels, while it did not affect the secretion of corresponding proteins into the culture medium of these cells. Application of N-acyl dopamines promoted BDNF release into the culture medium. Under conditions of OS, N-DDA also increased TRKB, TRKC and RET mRNA levels. Furthermore, N-acyl dopamines prevented cell death 24 h after OS induction and promoted the expression of antioxidant enzymes GPX1, GPX7, SOD1, SOD2 and CAT, as well as reduced the BAX/BCL2 mRNA ratio. These findings indicate that stimulation of the expression of neurotrophic factors and their receptors may underlie the neuroprotective effects of N-acyl dopamines in human neurons.

Transient receptor potential vanilloid channel 2 (TRPV2) is required for normal cardiac contractility. The stimulation of TRPV1 in isolated cardiomyocytes can aggravate the effect of hypoxia/ reoxygenation (H/R) on H9C2 cells. The knockout of the TRPV1 gene promotes increased tolerance of the isolated perfused heart to the impact of ischemia/reperfusion (I/R). However, activation of TRPV1 increases the resistance of the heart to I/R due to calcitonin gene-related peptide (CGRP) release from afferent nerve endings. It has been established that TRPV1 and TRPV2 are involved in the pathogenesis of myocardial infarction and, in all likelihood, ensure the cardiac tolerance to the ischemia/reperfusion. It has also been documented that the activation of TRPV4 negatively affects the stability of cardiomyocytes to the H/R. The blockade of TRPV4 can be considered as a new approach to the prevention of I/R injury of the heart. Studies also indicate that TRPV1 is involved in the pathogenesis of cardiac hypertrophy and that TRPV2 channels participate in the pathogenesis of dilated cardiomyopathy. Excessive expression of TRPV2 leads to chronic Ca2+- overload of cardiomyocytes, which may contribute to the development of cardiomyopathy., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Background: Nitroproston is a novel prostaglandin-based compound modified by NOdonating groups with potential application in obstructive respiratory diseases such as asthma and obstructive bronchitis. Nitroproston has been extensively studied using various pharmacological models. Its biological stability is still uncertain., Objective: The aim of the present study was to evaluate Nitroproston stability in vitro, as well as to identify and characterize its major biodegradation products., Methods: The principal biodegradation products of Nitroproston were identified in vitro using liquid chromatography/ion trap - time-of-flight mass-spectrometry. The postulated structure of metabolites was confirmed using authentic reference standards. Rat, rabbit and human plasma and human whole blood samples were used for comparative in vitro degradation study. Nitroproston and its biodegradation products in biological samples were measured by liquid chromatography/triple -stage quadrupole mass spectrometry., Results: Nitroproston is rapidly hydrolyzed in rat plasma to generate glycerol-1,3-dinitrate and prostaglandin E2. The latter can undergo conversion to cyclopentenone prostaglandins A2 and B2. Thereby less than 5% of the parent compound was observed in rat plasma at the first moment of incubation. A similar pattern was observed for rabbit plasma where half-life (T1/2) of Nitroproston was about 2.0 minutes. Nitroproston biodegradation rate for human plasma was the slowest (T1/2 = 2.1 h) among tested species, occurred more rapidly in whole blood (T1/2 = 14.8 min)., Conclusion: It was found that Nitroproston is rapidly hydrolyzed in rodent compared to human plasma incubations. Whereas Nitroproston is relatively stable in human plasma an enhanced hydrolytic activity was observed in whole human blood incubations. Extensive metabolism of Nitroproston in human whole blood was mainly associated with red blood cells. The observed interspecies variability highlights the need of suitable animal model selection for Nitroproston follow-up PK/PD studies., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background/aim: Dopamine amides of long chain fatty acids are a family of endogenous mammalian lipids with an unknown function; they are anti-proliferative for the C6 glioblastoma cell line. To assess their possible anti-cancer activity we evaluated their cytotoxicity for a set of cancer cell lines., Materials and Methods: Anti-proliferative and cytotoxic actions of these substances were evaluated in HOS, IMR-32, MCF-7, Namalwa, K-562 and HEK 293 cell lines (18 h incubation time) using MTT and lactate dehydrogenase (LDH) tests, accordingly., Results: All N-acyl dopamines (NADA) induced cell death in all cell lines tested with a 50% lethal dose (LD50) in the range of 0.5-80 μM, except for HEK-293. For HEK-293 only N-arachidonoyl epinephrine demonstrated an LD50 below 100 μM., Conclusion: According to the structure-activity relationship, N-acyl dopamines with an intact catechol group and a non-modified hydrophobic fatty acid residue are cytotoxic to cancer cell lines of various histological origins., (Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)