Presence of heterocyclic aromatic amines (HAs) in smoked “Provola” cheese from Calabria (Italy)

This study evaluated the residual levels of heterocyclic aromatic amines (HAs) in “Provola” cheese samples from Calabria, smoked using natural methods and using commercial buffered smoke. A comparative study of HAs concentrations was carried out on different portions of these samples: the rind, exterior part, core and on slice. Quantitative determination of HAs was carried out by HPLC using a fluorescence detector and analysis in HPLC–MS was conduced to confirm the presence of these amines. Residual levels of HAs were found in all naturally smoked “Provola” cheese samples. The results obtained showed that the smoking process performed using traditional methods contributes to HAs contamination while the use of commercial buffered smoke can be considered a safer technique for smoking of food.     

Effect of 2-amino-9H-pyrido[2,3-b]indole (AαC), a carcinogenic heterocyclic amine present in food,on atherosclerotic plaque development in apoE deficient mice

There is experimental and epidemiological evidence demonstrating that polycyclic aromatic hydrocarbons (PAHs) are involved in the pathogenesis of cardiovascular diseases. However, heterocyclic amines (HAs), a class of carcinogenic compounds present in food, which share many biochemical features with PAHs, have not received much attention. Previous reports have shown that the heterocyclic amine 2-amino-9H-pyrido[2,3-b]indole (AαC) binds and metabolically affects endothelial cells in animal models suggesting a potential role in vascular remodeling. The present study investigates the effect of exposure to HAs on atherosclerotic plaque development in the apoE^−/− mice. We observed that animals treated with AαC developed atherosclerotic lesions characterized by lower lipid content but richer in inflammatory cells and collagen content when compared with control animals. Moreover, atherosclerotic plaques from AαC-treated apoE^−/− mice were also smaller with a marked reduction in the tunica media thickness. Furthermore, total cholesterol levels were significantly reduced in AαC-treated apoE^−/− mice. In contrast to what has been previously reported for PAHs, we provide for the first time evidence that HAs may protect against cardiovascular disease by inducing stable atherosclerotic plaques and reducing circulating cholesterol levels. These results open new avenues to further investigate the role of these food-borne carcinogens in cardiovascular physiology and pathology.     

Neonatal co-lesion by DSP-4 and 5,7-DHT produces adulthood behavioral sensitization to dopamine D2 receptor agonists

To assess the possible modulatory effects of noradrenergic and serotoninergic neurons on dopaminergic neuronal activity, the noradrenergic and serotoninergic neurotoxins DSP-4 N-(2-chlorethyl)-N-ethyl-2-bromobenzylamine (50.0 mg/kg, sc) and 5,7-dihydroxytryptamine (5,7-DHT) (37.5 μg icv, half in each lateral ventricle), respectively, were administered toWistar rats on the first and third days of postnatal ontogeny, and dopamine (DA) agonist-induced behaviors were assessed in adulthood. At eight weeks, using an HPLC/ED technique, DSP-4 treatment was associated with a reduction in NE content of the corpus striatum (> 60%), hippocampus (95%), and frontal cortex (> 85%), while 5,7-DHT was associated with an 80–90% serotonin reduction in the same brain regions. DA content was unaltered in the striatum and the cortex. In the group lesioned with both DSP-4 and 5,7-DHT, quinpirole-induced (DA D₂ agonist) yawning, 7-hydroxy-DPAT-induced (DA D₃ agonist) yawning, and apomorphine-induced (non-selective DAagonist) stereotypies were enhanced. However, SKF 38393-induced (DA D₁ agonist) oral activity was reduced in the DSP-4 + 5,7-DHT group. These findings demonstrate that DA D₂-and D₃-agonist-induced behaviors are enhanced while DA D₁-agonist-induced behaviors are suppressed in adult rats in which brain noradrenergic and serotoninergic innervation of the brain has largely been destroyed. This study indicates that noradrenergic and serotoninergic neurons have a great impact on the development of DA receptor reactivity (sensitivity).     

Synthesis, antidepressant and antifungal evaluation of novel 2-chloro-8-methylquinoline amine derivatives

A new series of N-[(2-chloro-8-methylquinolin-3-yl)methyl]-(substituted)-aniline/butylamine/cyclohexylamine/benzylamine derivatives (4a-p) was synthesized by nucleophilic substitution reaction of 2-chloro-3-(chloromethyl)-8-methylquinoline 3 with various aliphatic and aromatic amines in absolute ethanol in the presence of triethylamine (TEA). The newly synthesized secondary amines were characterized by the combined use of IR, ¹H NMR, ¹³C NMR, mass spectral data and microanalyses. The antidepressant activity of the synthesized compounds (4a-p) was evaluated by Forced swim test in rats and their neurotoxicity was evaluated by the rotarod test. Test compounds and clomipramine were administered intraperitoneally at dose of 100 mg/kg and 20 mg/kg respectively. Preliminary antidepressant screening of compounds (4a-p) revealed that compounds 4b, 4c, 4d, 4e, 4i and 4o significantly (P < 0.01) reduces the duration of immobility time. These compounds were also tested in-vitro for MAO inhibitory effect. All the compounds were also screened for antifungal activity against Aspergillus niger MTCC 281, Aspergillus flavus MTCC 277, Monascus purpureus MTCC 369 and Penicillium citrinum NCIM 768 strains.     

Vacuum‐Ultraviolet Photopolymerisation of Amine‐Rich Thin Films

Nitrogen‐rich organic thin films were deposited by VUV‐assisted photochemical polymerisation of flowing C₂H₄/NH₃ mixtures. The fundamental reaction mechanisms of these binary gas mixtures were investigated as a function of the wavelength of two almost monochromatic VUV sources. Compositions of these “UV‐PE:N” films close to the surface were determined by XPS, and the amine concentrations and selectivities were quantified via chemical derivatisation. The UV‐PE:N films were compared with plasma polymers deposited using low‐pressure glow discharges in similar gas flow mixtures, “L‐PPE:N”; it is shown that VUV photochemistry is superior to plasma chemistry in producing almost monofunctional organic thin films.

     

Finding a place and leaving a mark in memory formation

Abstract

Preference for spatial locations to maximize favorable outcomes and minimize aversive experiences helps animals survive and adapt to the changing environment. Both visual and non-visual cues play a critical role in spatial navigation and memory of a place supports and guides these strategies. Here we present the neural, genetic and behavioral processes involved in place memory formation using Drosophila melanogaster with a focus on non-visual cue based spatial memories. The work presented here highlights the work done by Dr. Troy Zars and his colleagues with an emphasis on role of biogenic amines in learning, cell biological mechanisms of neural systems and behavioral plasticity of place conditioning.     

Serotonin is Critical for Rewarded Olfactory Short-Term Memory in Drosophila

Abstract: The biogenic amines dopamine, octopamine, and serotonin are critical in establishing normal memories. A common view for the amines in insect memory performance has emerged in which dopamine and octopamine are largely responsible for aversive and appetitive memories. Examination of the function of serotonin begins to challenge the notion of one amine type per memory because altering serotonin function also reduces aversive olfactory memory and place memory levels. Could the function of serotonin be restricted to the aversive domain, suggesting a more specific dopamine/serotonin system interaction? The function of the serotonergic system in appetitive olfactory memory was examined. By targeting the tetanus toxin light chain (TNT) and the human inwardly rectifying potassium channel (Kir2.1) to the serotonin neurons with two different GAL4 driver combinations, the serotonergic system was inhibited. Additional use of the GAL80^ts1 system to control expression of transgenes to the adult stage of the life cycle addressed a potential developmental role of serotonin in appetitive memory. Reduction in appetitive olfactory memory performance in flies with these transgenic manipulations, without altering control behaviors, showed that the serotonergic system is also required for normal appetitive memory. Thus, serotonin appears to have a more general role in Drosophila memory, and implies an interaction with both the dopaminergic and octopaminergic systems.