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Sample records for ache activity increased

  1. Hypocretin-1 causes G protein activation and increases ACh release in rat pons.

    PubMed

    Bernard, René; Lydic, Ralph; Baghdoyan, Helen A

    2003-10-01

    The effects of the arousal-promoting peptide hypocretin on brain stem G protein activation and ACh release were examined using 16 adult Sprague-Dawley rats. In vitro[35S]GTPgammaS autoradiography was used to test the hypothesis that hypocretin-1-stimulated G protein activation is concentration-dependent and blocked by the hypocretin receptor antagonist SB-334867. Activated G proteins were quantified in dorsal raphe nucleus (DR), locus coeruleus (LC) and pontine reticular nucleus oral part (PnO) and caudal part (PnC). Concentration-response data revealed a significant (P < 0.001) effect of hypocretin-1 (2-2000 nm) in all brain regions examined. Maximal increases over control levels of [35S]GTPgammaS binding were 37% (DR), 58% (LC), 52% (PnO) and 44% (PnC). SB-334867 (2 micro m) significantly (P < 0.002) blocked hypocretin-1 (200 nm)-stimulated [35S]GTPgammaS binding in all four nuclei. This is the first autoradiographic demonstration that hypocretin-1 activates G proteins in arousal-related brain stem nuclei as a result of specific receptor interactions. This finding suggests that some hypocretin receptors in brain stem couple to inhibitory G proteins. In vivo microdialysis was used to test the hypothesis that PnO administration of hypocretin-1 increases ACh release in PnO. Dialysis delivery of hypocretin-1 (100 micro m) significantly (P < 0.002) increased (87%) ACh release. This finding is consistent with the interpretation that one mechanism by which hypocretin promotes arousal is by enhancing cholinergic neurotransmission in the pontine reticular formation.

  2. Circannual rhythms of acetylcholinesterase (AChE) activity in the freshwater fish Cnesterodon decemmaculatus.

    PubMed

    Menéndez-Helman, Renata J; Ferreyroa, Gisele V; dos Santos Afonso, Maria; Salibián, Alfredo

    2015-01-01

    The use of biomarkers as a tool to assess responses of organisms exposed to pollutants in toxicity bioassays, as well as in aquatic environmental risk assessment protocols, requires the understanding of the natural fluctuation of the particular biomarker. The aim of this study was to characterize the intrinsic variations of acetylcholinesterase (AChE) activity in tissues of a native freshwater teleost fish to be used as biomarker in toxicity tests, taking into account both seasonal influence and fish size. Specific AChE activity was measured by the method of Ellman et al. (1961) in homogenates of fish anterior section finding a seasonal variability. The highest activity was observed in summer, decreasing significantly below 40% in winter. The annual AChE activity cycle in the anterior section was fitted to a sinusoidal function with a period of 11.2 months. Moreover, an inverse relationship between enzymatic activity and the animal size was established. The results showed that both the fish length and seasonal variability affect AChE activity. AChE activity in fish posterior section showed a similar trend to that in the anterior section, while seasonal variations of the activity in midsection were observed but differences were not statistically significant. In addition, no relationship between AChE and total tissue protein was established in the anterior and posterior sections suggesting that the circannual rhythms observed are AChE-specific responses. Results highlight the importance of considering both the fish size and season variations to reach valid conclusions when AChE activity is employed as neurotoxicity biomarker.

  3. Integrative Characterization of Toxic Response of Zebra Fish (Danio rerio) to Deltamethrin Based on AChE Activity and Behavior Strength

    PubMed Central

    Ren, Qing; Zhang, Tingting; Li, Shangge; Yang, Meiyi; Pan, Hongwei; Xu, Shiguo; Qi, Li; Chon, Tae-Soo

    2016-01-01

    In order to characterize the toxic response of zebra fish (Danio rerio) to Deltamethrin (DM), behavior strength (BS) and muscle AChE activity of zebra fish were investigated. The results showed that the average values of both BS and AChE activity showed a similarly decreased tendency as DM concentration increased, which confirmed the dose-effect relationship, and high and low levels of AChE and BS partly matched low and high levels of exposure concentrations in self-organizing map. These indicated that AChE and BS had slight different aspects of toxicity although overall trend was similar. Behavior activity suggested a possibility of reviving circadian rhythm in test organisms after exposure to the chemical in lower concentration (0.1 TU). This type of rhythm disappeared in higher concentrations (1.0 TU and 2.0 TU). Time series trend analysis of BS and AChE showed an evident time delayed effect of AChE, and a 2 h AChE inhibition delay with higher correlation coefficients (r) in different treatments was observed. It was confirmed that muscle AChE inhibition of zebra fish is a factor for swimming behavior change, though there was a 2 h delay, and other factors should be investigated to illustrate the detailed behavior response mechanism. PMID:27999812

  4. Increased ratio of rapsyn to ACh receptor stabilizes postsynaptic receptors at the mouse neuromuscular synapse

    PubMed Central

    Gervásio, Othon L; Phillips, William D

    2005-01-01

    The metabolic turnover of nicotinic ACh receptors (AChR) at the neuromuscular synapse is regulated over a tenfold range by innervation status, muscle electrical activity and neural agrin, but the downstream effector of such changes has not been defined. The AChR-associated protein rapsyn is essential for forming AChR clusters during development. Here, rapsyn was tagged with enhanced green fluorescent protein (EGFP) to begin to probe its influence at the adult synapse. In C2 myotubes, rapsyn–EGFP participated with AChR in agrin-induced AChR cluster formation. When electroporated into the tibialis anterior muscle of young adult mice, rapsyn–EGFP accumulated in discrete subcellular structures, many of which colocalized with Golgi markers, consistent with the idea that rapsyn assembles with AChR in the exocytic pathway. Rapsyn–EGFP also targeted directly to the postsynaptic membrane where it occupied previously vacant rapsyn binding sites, thereby increasing the rapsyn to AChR ratio. At endplates displaying rapsyn–EGFP, the metabolic turnover of AChR (labelled with rhodamine-α-bungarotoxin) was slowed. Thus, the metabolic half-life of receptors at the synapse may be modulated by local changes in the subsynaptic ratio of rapsyn to AChR. PMID:15550459

  5. Effect of pharmaceuticals exposure on acetylcholinesterase (AchE) activity and on the expression of AchE gene in the monogonont rotifer, Brachionus koreanus.

    PubMed

    Rhee, Jae-Sung; Kim, Bo-Mi; Jeong, Chang-Bum; Park, Heum Gi; Leung, Kenneth Mei Yee; Lee, Young-Mi; Lee, Jae-Seong

    2013-11-01

    Pharmaceuticals are widely used in human and veterinary medicine. However, they are emerging as a significant contaminant in aquatic environments through wastewater. Due to the persistent and accumulated properties of pharmaceuticals via the food web, their potential harmful effects on aquatic animals are a great concern. In this study, we investigated the effects of six pharmaceuticals: acetaminophen, ATP; atenolol, ATN; carbamazepine, CBZ; oxytetracycline, OTC; sulfamethoxazole, SMX; and trimethoprim, TMP on acetylcholinesterase (AChE; EC 3.1.1.7) activity and its transcript expression with chlorpyrifos (as a positive control) in the monogonont rotifer, Brachionus koreanus. ATP, CBZ, and TMP exposure also remarkably inhibited Bk-AChE activity at 100 μg/L (24 h) and 1000 μg/L (12 h and 24 h). ATP, CBZ, and TMP exposure showed a significant decrease in the Bk-AChE mRNA level in a concentration-dependent manner. However, in the case of OTC and SMX, a slight decrease in Bk-AChE mRNA expression was found but only at the highest concentration. The time-course experiments showed that ATP positively induced Bk-AChE mRNA 12 h after exposure at both 100 and 1000 μg/L, while the Bk-AChE mRNA expression was significantly downregulated over 6 to 24 h after exposure to 1000 μg/L of CBZ, OTC, SMX, and TMP. Our findings suggest that Bk-AChE would be a useful biomarker for risk assessment of pharmaceutical compounds as an early signal of their toxicity in aquatic environments. Particularly, ATP, CBZ, and TMP may have a toxic cholinergic effect on rotifer B. koreanus by inhibiting AChE activity.

  6. Design, synthesis, and AChE inhibitory activity of new benzothiazole-piperazines.

    PubMed

    Demir Özkay, Ümide; Can, Özgür Devrim; Sağlık, Begüm Nurpelin; Acar Çevik, Ulviye; Levent, Serkan; Özkay, Yusuf; Ilgın, Sinem; Atlı, Özlem

    2016-11-15

    In the current study, 14 new benzothiazole-piperazine compounds were designed to meet the structural requirements of acetylcholine esterase (AChE) inhibitors. The target compounds were synthesised in three steps. Structures of the newly synthesised compounds (7-20) were confirmed using IR, (1)H NMR, (13)C NMR, and HRMS methods. The inhibitory potential of the compounds on AChE (E.C.3.1.1.7, from electric eel) was then investigated. Among the compounds, 19 and 20 showed very good activity on AChE enzyme. Kinetics studies were performed to observe the effects of the most active compounds on the substrate-enzyme relationship. Cytotoxicity studies, genotoxicity studies, and theoretical calculation of pharmacokinetics properties were also carried out. The compounds 19 and 20 were found to be nontoxic in both of the toxicity assays. A good pharmacokinetics profile was predicted for the synthesised compounds. Molecular docking studies were performed for the most active compounds, 19 and 20, and interaction modes with enzyme active sites were determined. Docking studies indicated a strong interaction between the active sites of AChE enzyme and the analysed compounds.

  7. Extracts and constituents of Leontopodium alpinum enhance cholinergic transmission: Brain ACh increasing and memory improving properties

    PubMed Central

    Hornick, Ariane; Schwaiger, Stefan; Rollinger, Judith M.; Vo, Nguyen Phung; Prast, Helmut; Stuppner, Hermann

    2012-01-01

    Leontopodium alpinum (‘Edelweiss’) was phytochemically investigated for constituents that might enhance cholinergic neurotransmission. The potency to increase synaptic availability of acetylcholine (ACh) in rat brain served as key property for the bioguided isolation of cholinergically active compounds using different chromatographic techniques. The dichlormethane (DCM) extract of the root, fractions and isolated constituents were injected i.c.v. and the effect on brain ACh was detected via the push–pull technique. The DCM extract enhanced extracellular ACh concentration in rat brain and inhibited acetylcholinesterase (AChE) in vitro. The extracellular level of brain ACh was significantly increased by the isolated sesquiterpenes, isocomene and 14-acetoxyisocomene, while silphiperfolene acetate and silphinene caused a small increasing tendency. Only silphiperfolene acetate showed in vitro AChE inhibitory activity, thus suggesting the other sesquiterpenes to stimulate cholinergic transmission by an alternative mechanism of action. Isocomene was further investigated with behavioural tasks in mice. It restored object recognition in scopolamine-impaired mice and showed nootropic effects in the T-maze alternation task in normal and scopolamine-treated mice. Additionally, this sesquiterpene reduced locomotor activity of untreated mice in the open field task, while the activity induced by scopolamine was abolished. The enhancement of synaptic availability of ACh, the promotion of alternation, and the amelioration of scopolamine-induced deficit are in accordance with a substance that amplifies cholinergic transmission. Whether the mechanism of action is inhibition of AChE or another pro-cholinergic property remains to be elucidated. Taken together, isocomene and related constituents of L. alpinum deserve further interest as potential antidementia agents in brain diseases associated with cholinergic deficits. PMID:18541221

  8. A selective molecularly imprinted polymer for immobilization of acetylcholinesterase (AChE): an active enzyme targeted and efficient method.

    PubMed

    Demirci, Gökhan; Doğaç, Yasemin İspirli; Teke, Mustafa

    2015-11-01

    In the present study, we immobilized acetylcholinesterase (AChE) enzyme onto acetylcholine removed imprinted polymer and acetylcholine containing polymer. First, the polymers were produced with acetylcholine, substrate of AChE, by dispersion polymerization. Then, the enzyme was immobilized onto the polymers by using two different methods: In the first method (method A), acetylcholine was removed from the polymer, and then AChE was immobilized onto this polymer (acetylcholine removed imprinted polymer). In the second method (method B), AChE was immobilized onto acetylcholine containing polymer by affinity. In method A, enzyme-specific species (binding sites) occurred by removing acetylcholine from the polymer. The immobilized AChE reached 240% relative specific activity comparison with free AChE because the active enzyme molecules bounded onto the polymer. Transmission electron microscopy results were taken before and after immobilization of AChE for the assessment of morphological structure of polymer. Also, the experiments, which include optimum temperature (25-65 °C), optimum pH (3-10), thermal stability (4-70 °C), kinetic parameters, operational stability and reusability, were performed to determine the characteristic of the immobilized AChE.

  9. In vitro effect of H2O 2, some transition metals and hydroxyl radical produced via fenton and fenton-like reactions, on the catalytic activity of AChE and the hydrolysis of ACh.

    PubMed

    Méndez-Garrido, Armando; Hernández-Rodríguez, Maricarmen; Zamorano-Ulloa, Rafael; Correa-Basurto, José; Mendieta-Wejebe, Jessica Elena; Ramírez-Rosales, Daniel; Rosales-Hernández, Martha Cecilia

    2014-11-01

    It is well known that the principal biomolecules involved in Alzheimer's disease (AD) are acetylcholinesterase (AChE), acetylcholine (ACh) and the amyloid beta peptide of 42 amino acid residues (Aβ42). ACh plays an important role in human memory and learning, but it is susceptible to hydrolysis by AChE, while the aggregation of Aβ42 forms oligomers and fibrils, which form senile plaques in the brain. The Aβ42 oligomers are able to produce hydrogen peroxide (H2O2), which reacts with metals (Fe(2+), Cu(2+), Cr(3+), Zn(2+), and Cd(2+)) present at high concentrations in the brain of AD patients, generating the hydroxyl radical ((·)OH) via Fenton (FR) and Fenton-like (FLR) reactions. This mechanism generates high levels of free radicals and, hence, oxidative stress, which has been correlated with the generation and progression of AD. Therefore, we have studied in vitro how AChE catalytic activity and ACh levels are affected by the presence of metals (Fe(3+), Cu(2+), Cr(3+), Zn(2+), and Cd(2+)), H2O2 (without Aβ42), and (·) OH radicals produced from FR and FLR. The results showed that the H2O2 and the metals do not modify the AChE catalytic activity, but the (·)OH radical causes a decrease in it. On the other hand, metals, H2O2 and (·)OH radicals, increase the ACh hydrolysis. This finding suggests that when H2O2, the metals and the (·)OH radicals are present, both, the AChE catalytic activity and ACh levels diminish. Furthermore, in the future it may be interesting to study whether these effects are observed when H2O2 is produced directly from Aβ42.

  10. Downregulated expression of microRNA-124 in pediatric intestinal failure patients modulates macrophages activation by inhibiting STAT3 and AChE

    PubMed Central

    Xiao, Yong-Tao; Wang, Jun; Lu, Wei; Cao, Yi; Cai, Wei

    2016-01-01

    Intestinal inflammation plays a critical role in the pathogenesis of intestinal failure (IF). The macrophages are essential to maintain the intestinal homeostasis. However, the underlying mechanisms of intestinal macrophages activation remain poorly understood. Since microRNAs (miRNAs) have pivotal roles in regulation of immune responses, here we aimed to investigate the role of miR-124 in the activation of intestinal macrophages. In this study, we showed that the intestinal macrophages increased in pediatric IF patients and resulted in the induction of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). The miRNA fluorescence in situ hybridization analysis showed that the expression of miR-124 significantly reduced in intestinal macrophages in IF patients. Overexpression of miR-124 was sufficient to inhibit intestinal macrophages activation by attenuating production of IL-6 and TNF-α. Further studies showed that miR-124 could directly target the 3′-untranslated region of both signal transducer and activator of transcription 3 (STAT3) and acetylcholinesterase (AChE) mRNAs, and suppress their protein expressions. The AChE potentially negates the cholinergic anti-inflammatory signal by hydrolyzing the acetylcholine. We here showed that intestinal macrophages increasingly expressed the AChE and STAT3 in IF patients when compared with controls. The inhibitors against to STAT3 and AChE significantly suppressed the lipopolysaccharides-induced IL-6 and TNF-α production in macrophages. Taken together, these findings highlight an important role for miR-124 in the regulation of intestinal macrophages activation, and suggest a potential application of miR-124 in pediatric IF treatment regarding as suppressing intestinal inflammation. PMID:27977009

  11. Evaluation of the Toxicity, AChE Activity and DNA Damage Caused by Imidacloprid on Earthworms, Eisenia fetida.

    PubMed

    Wang, Kai; Qi, Suzhen; Mu, Xiyan; Chai, Tingting; Yang, Yang; Wang, Dandan; Li, Dongzhi; Che, Wunan; Wang, Chengju

    2015-10-01

    Imidacloprid is a well-known pesticide and it is timely to evaluate its toxicity to earthworms (Eisenia fetida). In the present study, the effect of imidacloprid on reproduction, growth, acetylcholinesterase (AChE) and DNA damage in earthworms was assessed using an artificial soil medium. The median lethal concentration (LC50) and the median number of hatched cocoons (EC50) of imidacloprid to earthworms was 3.05 and 0.92 mg/kg respectively, the lowest observed effect concentration of imidacloprid about hatchability, growth, AChE activity and DNA damage was 0.02, 0.5, 0.1 and 0.5 mg/kg, respectively.

  12. Nerolidol-loaded nanospheres prevent behavioral impairment via ameliorating Na(+), K(+)-ATPase and AChE activities as well as reducing oxidative stress in the brain of Trypanosoma evansi-infected mice.

    PubMed

    Baldissera, Matheus D; Souza, Carine F; Grando, Thirssa H; Moreira, Karen L S; Schafer, Andressa S; Cossetin, Luciana F; da Silva, Ana P T; da Veiga, Marcelo L; da Rocha, Maria Izabel U M; Stefani, Lenita M; da Silva, Aleksandro S; Monteiro, Silvia G

    2017-02-01

    The aim of this study was to investigate the effect of nerolidol-loaded nanospheres (N-NS) on the treatment of memory impairment caused by Trypanosoma evansi in mice, as well as oxidative stress, and Na(+), K(+)-ATPase and acetylcholinesterase (AChE) activities in brain tissue. Animals were submitted to behavioral tasks (inhibitory avoidance task and open-field test) 4 days postinfection (PI). Reactive oxygen species (ROS) and thiobarbituric acid-reactive substance (TBARS) levels and catalase (CAT), superoxide dismutase (SOD), Na(+), K(+)-ATPase and AChE activities were measured on the fifth-day PI. T. evansi-infected mice showed memory deficit, increased ROS and TBARS levels and SOD and AChE activities, and decreased CAT and Na(+), K(+)-ATPase activities compared to uninfected mice. N-NS prevented memory impairment and oxidative stress parameters (except SOD activity), while free nerolidol (N-F) restored only CAT activity. Also, N-NS treatment was able to prevent alterations in Na(+), K(+)-ATPase and AChE activities caused by T. evansi infection. A significantly negative correlation was observed between memory and ROS production (p < 0.001; r = -0.941), as well as between memory and AChE activity (p < 0.05; r = -0.774). On the contrary, a significantly positive correlation between memory and Na(+), K(+)-ATPase activity was observed (p < 0.01; r = 0.844). In conclusion, N-NS was able to reverse memory impairment and to prevent increased ROS and TBARS levels due to amelioration of Na(+), K(+)-ATPase and AChE activities and to activation of the antioxidant enzymes, respectively. These results suggest that N-NS treatment may be a useful strategy to treat memory dysfunction and oxidative stress caused by T. evansi infection.

  13. AChE and EROD activities in two echinoderms, Holothuria leucospilota and Holoturia atra (Holothuroidea), in a coral reef (Reunion Island, South-western Indian Ocean).

    PubMed

    Kolasinski, Joanna; Taddei, Dorothée; Cuet, Pascale; Frouin, Patrick

    2010-01-01

    AChE and EROD activities were investigated in two holothurian species, Holothuria leucospilota and Holoturia atra, from a tropical coral reef. These organisms were collected from 3 back-reef stations, where temperature and salinity were homogeneous. The activity levels of both AChE and EROD varied significantly between the two species, but were in the range of values determined in other echinoderm species. AChE activity levels were higher in the longitudinal muscle than in the tentacle tegument. Among the several tissues tested, the digestive tract wall exhibited higher EROD activity levels. Sex did not influence AChE and EROD activity levels in both species. Animal biomass and EROD activity levels were only correlated in the tegument tissue of H. atra, and we hypothesize a possible influence of age. EROD activity did not show intraspecific variability. A significant relationship was found between AChE activity and Cuvierian tubules time of expulsion in Holothuria leucospilota. Individuals collected at the southern site presented both lower AChE activity levels and Cuvierian tubules time of expulsion, indicating possible neural disturbance. More information on holothurians biology and physiology is needed to further assess biomarkers in these key species. This study is the first of its kind performed in the coastal waters of Reunion Island and data obtained represent reference values.

  14. Selective activation of α7 nicotinic acetylcholine receptor (nAChRα7) inhibits muscular degeneration in mdx dystrophic mice.

    PubMed

    Leite, Paulo Emílio Correa; Gandía, Luís; de Pascual, Ricardo; Nanclares, Carmen; Colmena, Inés; Santos, Wilson C; Lagrota-Candido, Jussara; Quirico-Santos, Thereza

    2014-07-21

    Amount evidence indicates that α7 nicotinic acetylcholine receptor (nAChRα7) activation reduces production of inflammatory mediators. This work aimed to verify the influence of endogenous nAChRα7 activation on the regulation of full-blown muscular inflammation in mdx mouse with Duchenne muscular dystrophy. We used mdx mice with 3 weeks-old at the height myonecrosis, and C57 nAChRα7(+/+) wild-type and nAChRα7(-/-) knockout mice with muscular injury induced with 60µL 0.5% bupivacaine (bp) in the gastrocnemius muscle. Pharmacological treatment included selective nAChRα7 agonist PNU282987 (0.3mg/kg and 1.0mg/kg) and the antagonist methyllycaconitine (MLA at 1.0mg/kg) injected intraperitoneally for 7 days. Selective nAChRα7 activation of mdx mice with PNU282987 reduced circulating levels of lactate dehydrogenase (LDH, a marker of cell death by necrosis) and the area of perivascular inflammatory infiltrate, and production of inflammatory mediators TNFα and metalloprotease MMP-9 activity. Conversely, PNU282987 treatment increased MMP-2 activity, an indication of muscular tissue remodeling associated with regeneration, in both mdx mice and WTα7 mice with bp-induced muscular lesion. Treatment with PNU282987 had no effect on α7KO, and MLA abolished the nAChRα7 agonist-induced anti-inflammatory effect in both mdx and WT. In conclusion, nAChRα7 activation inhibits muscular inflammation and activates tissue remodeling by increasing muscular regeneration. These effects were not accompanied with fibrosis and/or deposition of non-functional collagen. The nAChRα7 activation may be considered as a potential target for pharmacological strategies to reduce inflammation and activate mechanisms of muscular regeneration.

  15. Novel assay utilizing fluorochrome-tagged physostigmine (Ph-F) to in situ detect active acetylcholinesterase (AChE) induced during apoptosis.

    PubMed

    Huang, Xuan; Lee, Brian; Johnson, Gary; Naleway, John; Guzikowski, Anthony; Dai, Wei; Darzynkiewicz, Zbigniew

    2005-01-01

    It was recently reported that acetylcholinesterase (AChE) is expressed in cells undergoing apoptosis and that its presence is essential for assembly of the apoptosome and subsequent caspase-9 activation. To obtain a marker of active AChE that could assay this enzyme in live intact cells and be applicable to fluorescence microscopy and cytometry, the fluorescein-tagged physostigmine (Ph-F), high affinity ligand (inhibitor) reactive with the active center of AChE, was constructed and tested for its ability to in situ label AChE and measure its induction during apoptosis. Ph-F inhibited cholinesterase activity in vitro (IC50 = 10(-6) and 5 x 10(-6) M for equine butyrylcholinesterase and human erythrocyte AChE, respectively) and was a selective marker of cells and structures that were AChE-positive. Thus, exposure of mouse bone marrow cells to Ph-F resulted in the exclusive labeling of megakaryocytes, and of the diaphragm muscle, preferential labeling of the nerve-muscle junctions (end-plates). During apoptosis of carcinoma HeLa cells and leukemic HL-60 or Jurkat cells triggered either by the DNA topoisomerase 1 inhibitor topotecan (TPT) or by oxidative stress (H2O2), the cells become reactive with Ph-F. Their Ph-F derived fluorescence was measured by flow and laser scanning cytometry. The appearance of Ph-F binding sites during apoptosis was preceded by the loss of mitochondrial potential, was concurrent with the presence of activated caspases, and was followed by loss of membrane integrity. At a very early stage of apoptosis, when nucleolar segregation was apparent, the Ph-F binding sites were distinctly localized within the nucleolus and at later stages of apoptosis in the cytoplasm. During apoptosis triggered by TPT, Ph-F binding was preferentially induced in S-phase cells. Our data on megakaryocytes and end-plates indicate that Ph-F reacts with active sites of AChE, and can be used to reveal the presence of this enzyme in live cells and possibly to study its

  16. Activity of nAChRs containing alpha9 subunits modulates synapse stabilization via bidirectional signaling programs.

    PubMed

    Murthy, Vidya; Taranda, Julián; Elgoyhen, A Belén; Vetter, Douglas E

    2009-12-01

    Although the synaptogenic program for cholinergic synapses of the neuromuscular junction is well known, little is known of the identity or dynamic expression patterns of proteins involved in non-neuromuscular nicotinic synapse development. We have previously demonstrated abnormal presynaptic terminal morphology following loss of nicotinic acetylcholine receptor (nAChR) alpha9 subunit expression in adult cochleae. However, the molecular mechanisms underlying these changes have remained obscure. To better understand synapse formation and the role of cholinergic activity in the synaptogenesis of the inner ear, we exploit the nAChR alpha9 subunit null mouse. In this mouse, functional acetylcholine (ACh) neurotransmission to the hair cells is completely silenced. Results demonstrate a premature, effusive innervation to the synaptic pole of the outer hair cells in alpha9 null mice coinciding with delayed expression of cell adhesion proteins during the period of effusive contact. Collapse of the ectopic innervation coincides with an age-related hyperexpression pattern in the null mice. In addition, we document changes in expression of presynaptic vesicle recycling/trafficking machinery in the alpha9 null mice that suggests a bidirectional information flow between the target of the neural innervation (the hair cells) and the presynaptic terminal that is modified by hair cell nAChR activity. Loss of nAChR activity may alter transcriptional activity, as CREB binding protein expression is decreased coincident with the increased expression of N-Cadherin in the adult alpha9 null mice. Finally, by using mice expressing the nondesensitizing alpha9 L9'T point mutant nAChR subunit, we show that increased nAChR activity drives synaptic hyperinnervation.

  17. Biochemical effects of glyphosate based herbicide, Excel Mera 71 on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content on teleostean fishes.

    PubMed

    Samanta, Palas; Pal, Sandipan; Mukherjee, Aloke Kumar; Ghosh, Apurba Ratan

    2014-09-01

    Effects of glyphosate based herbicide, Excel Mera 71 at a dose of 17.20mg/l on enzyme activities of acetylcholinesterase (AChE), lipid peroxidation (LPO), catalase (CAT), glutathione-S-transferase (GST) and protein content were measured in different tissues of two Indian air-breathing teleosts, Anabas testudineus (Bloch) and Heteropneustes fossilis (Bloch) during an exposure period of 30 days under laboratory condition. AChE activity was significantly increased in all the investigated tissues of both fish species and maximum elevation was observed in brain of H. fossilis, while spinal cord of A. testudineus showed minimum increment. Fishes showed significant increase LPO levels in all the tissues; highest was observed in gill of A. testudineus but lowest LPO level was observed in muscle of H. fossilis. CAT was also enhanced in both the fishes, while GST activity in liver diminished substantially and minimum was observed in liver of A. testudineus. Total protein content showed decreased value in all the tissues, maximum reduction was observed in liver and minimum in brain of A. testudineus and H. fossilis respectively. The results indicated that Excel Mera 71 caused serious alterations in the enzyme activities resulting into severe deterioration of fish health; so, AChE, LPO, CAT and GST can be used as suitable indicators of herbicidal toxicity.

  18. The structure-AChE inhibitory activity relationships study in a series of pyridazine analogues.

    PubMed

    Saracoglu, M; Kandemirli, F

    2009-07-01

    The structure-activity relationships (SAR) are investigated by means of the Electronic-Topological Method (ETM) followed by the Neural Networks application (ETM-NN) for a class of anti-cholinesterase inhibitors (AChE, 53 molecules) being pyridazine derivatives. AChE activities of the series were measured in IC(50) units, and relative to the activity levels, the series was partitioned into classes of active and inactive compounds. Based on pharmacophores and antipharmacophores calculated by the ETM-software as sub-matrices containing important spatial and electronic characteristics, a system for the activity prognostication is developed. Input data for the ETM were taken as the results of conformational and quantum-mechanics calculations. To predict the activity, we used one of the most well known neural networks, namely, the feed-forward neural networks (FFNNs) trained with the back propagation algorithm. The supervised learning was performed using a variant of FFNN known as the Associative Neural Networks (ASNN). The result of the testing revealed that the high ETM's ability of predicting both activity and inactivity of potential AChE inhibitors. Analysis of HOMOs for the compounds containing Ph1 and APh1 has shown that atoms with the highest values of the atomic orbital coefficients are mainly those atoms that enter into the pharmacophores. Thus, the set of pharmacophores and antipharmacophores found as the result of this study forms a basis for a system of the anti-cholinesterase activity prediction.

  19. The acetylcholinesterase (AChE) inhibition analysis of medaka (Oryzias latipes) in the exposure of three insecticides.

    PubMed

    Zhu, Jianping; Huan, Cheng; Si, Guiyun; Yang, Haitang; Yin, Li; Ren, Qing; Ren, Baixiang; Fu, Rongshu; Miao, Mingsheng; Ren, Zongming

    2015-03-01

    The continuous effects on Acetylcholinesterase (AChE) activity of medaka (Oryzias latipes) caused by dichlorvos, methomyl and deltamethrin in vivo were investigated, and the trends of AChE activity inhibition due to the influence of these insecticides were discussed. The LC50-24h of dichlorvos, methomyl and deltamethrin on medaka were 2.3 mg/L, 0.2 mg/L, and 2.9×10(-3) mg/L respectively. The result suggested that at the beginning of the exposure, the AChE activity might increase, and the AChE activity in dead individuals was obviously lower than the live individuals. Though the de novo synthesis of AChE in medaka might help the AChE activity recover, the trends during the exposure in different treatments were downward, and it showed both exposure time and concentration dependent. Meanwhile, higher temperature might cause the AChE inhibition earlier due to the higher metabolic rate. Therefore, as a specific biomarker for organophosphate, carbamate pesticides and pyrethroids, the degree of the AChE inhibition with in vivo conditions is a good tool in continuous monitoring of insecticides, which may induce the nerve conduction disorders.

  20. Activation of volume-regulated Cl− channels by ACh and ATP in Xenopus follicles

    PubMed Central

    Pérez-Samartín, Alberto L; Miledi, Ricardo; Arellano, Rogelio O

    2000-01-01

    Osmolarity-dependent ionic currents from follicle-enclosed Xenopus oocytes (follicles) were studied using electrophysiological techniques. Whole follicle currents were monitored using a two-electrode voltage clamp and single-channel activity was measured using the patch-clamp technique.In follicles held at -60 mV two chloride currents were activated in external hyposmotic solutions. One was the habitual volume-regulated current elicited by external hyposmolarity (ICl,swell), and the second was a slow and smooth current (Sin) generated by ACh or ATP application.In follicles, the permeability ratios for different anions with respect to Cl− were similar for both ICl,swell and Sin, with a sequence of: SCN− > I− > Br−≥ NO3−≥ Cl− > gluconate ≥ cyclamate > acetate > SO42−.Extracellular ATP blocked the outward component of Sin. Also, extracellular pH modulated the inactivation kinetics of Sin elicited by ACh; e.g. inactivation at +80 mV was ∼100% slower at pH 8.0 compared with that at pH 6.0.Lanthanides inhibited ICl,swell and Sin. La3+ completely inhibited ICl,swell with a half-maximal inhibitory concentration (IC50) of 17 ± 1.9 μm, while Sin was blocked up to 55% with an apparent IC50 of 36 ± 2.6 μm.Patch-clamp recordings in follicular cells showed that hyposmotic challenge opened inward single-channel currents. The single channel conductance (4.7 ± 0.4 pS) had a linear current-voltage relationship with a reversal membrane potential close to −20 mV. This single-channel activity was increased by application of ACh or ATP.The ICl,swell generation was not affected by pirenzepine or metoctramine, and did not affect the purinergic activation of the chloride current named Fin. Thus, ICl,swell was not generated via neurotransmitters released during cellular swelling.All together, equal discrimination for different anions, similar modulatory effects by extracellular pH, the blocking effects by ATP and La3+, and the same single-channel activity

  1. AChE and the amyloid precursor protein (APP) - Cross-talk in Alzheimer's disease.

    PubMed

    Nalivaeva, Natalia N; Turner, Anthony J

    2016-11-25

    The amyloid precursor protein (APP) and acetylcholinesterase (AChE) are multi-faceted proteins with a wide range of vital functions, both crucially linked with the pathogenesis of Alzheimer's disease (AD). APP is the precursor of the Aβ peptide, the pathological agent in AD, while AChE is linked to its pathogenesis either by increasing cholinergic deficit or exacerbating Aβ fibril formation and toxicity. As such, both proteins are the main targets in AD therapeutics with AChE inhibitors being currently the only clinically available AD drugs. In our studies we have demonstrated an important inter-relation in functioning of these proteins. Both can be released from the cell membrane and we have shown that AChE shedding involves a metalloproteinase-mediated mechanism which, like the α-secretase dependent cleavage of APP, is stimulated by cholinergic agonists. Overexpression of the neuronal specific isoform APP695 in neuronal cells substantially decreased levels of the AChE mRNA, protein and catalytic activity accompanied by a similar decrease in mRNA levels of the AChE membrane anchor, PRiMA (proline rich membrane anchor). We further established that this regulation does not involve APP processing and its intracellular domain (AICD) but requires the E1 region of APP, specifically its copper-binding domain. On the contrary, siRNA knock-down of APP in cholinergic SN56 cells resulted in a significant upregulation of AChE mRNA levels. Hence APP may influence AChE physiology while released AChE may regulate amyloidogenesis through multiple mechanisms suggesting novel therapeutic targets.

  2. Further studies on the control of ACh sensitivity by muscle activity in the rat.

    PubMed Central

    Lomo, T; Westgaard, R H

    1975-01-01

    1. Denervated rat soleus muscles were stimulated directly through chronically implanted electrodes and the influence of different amounts and patterns of stimuli on the acetylcholine (ACh) sensitivity of the muscle was studied. The number of stimuli was varied by giving similar trains of stimuli (10 Hz for 10 sec) at different intervals (0 to 12 hr). The pattern of stimulation was varied by giving different trains of stimuli (100 Hz for 1 sec, 10 Hz for 10 sec and 1 Hz continuously) as the same average frequency of stimulation (1 Hz). 2. Stimulation usually started 5 days after the denervation when ACh hypersensitivity was fully developed. Most stimulation procedures reduced extrajunctional ACh sensitivity to normal or below normal values within 5-21 days, and these levels were maintained on prolonged stimulation. 3. The rate at which ACh hypersensitivity disappeared increased with increasing amount and frequency of stimulation. However, as few as 100 stimuli given every 5-5 hr for 3 weeks caused a tenfold reduction of sensitivity. 4. The stimulation had little or no effect on the ACh sensitivity at the end plate. Along the rest of the fibre the sensitivity was reduced at approximately the same rate except near the tendons where it appeared to fall more slowly in some fibres. 5. The stimulation restored the resting membrane potential of the denervated fibres to normal. PMID:1206569

  3. A facile stereoselective synthesis of dispiro-indeno pyrrolidine/pyrrolothiazole-thiochroman hybrids and evaluation of their antimycobacterial, anticancer and AchE inhibitory activities.

    PubMed

    Bharkavi, Chelliah; Vivek Kumar, Sundaravel; Ashraf Ali, Mohamed; Osman, Hasnah; Muthusubramanian, Shanmugam; Perumal, Subbu

    2016-11-15

    A facile stereoselective synthesis of novel dispiro indeno pyrrolidine/pyrrolothiazole-thiochroman hybrids has been achieved by 1,3-dipolar cycloaddition of azomethine ylides, generated in situ from ninhydrin and sarcosine/thiaproline, on a series of 3-benzylidenethiochroman-4-ones. The synthesised compounds were screened for their antimycobacterial, anticancer and AchE inhibition activities. Compound 4l (IC50 1.07μM) has been found to exhibit the most potent antimycobacterial activity compared to cycloserine (12 times), pyrimethamine (37 times) and ethambutol (IC50 <1.56μM) and 6l (IC50=2.87μM) is more active than both cycloserine (4 times) and pyrimethamine (12 times). Three compounds, 4a, 6b and 6i, display good anticancer activity against CCRF-CEM cell lines. Compounds 6g and 4g display maximum AchE inhibitory activity with IC50 values of 1.10 and 1.16μmol/L respectively.

  4. Remarkably increased resistin levels in anti-AChR antibody-positive myasthenia gravis.

    PubMed

    Zhang, Da-Qi; Wang, Rong; Li, Ting; Li, Xin; Qi, Yuan; Wang, Jing; Yang, Li

    2015-06-15

    Resistin is a pro-inflammatory cytokine involved in the pathogenesis of autoimmune diseases. To investigate serum resistin levels in patients with myasthenia gravis (MG) and determine if there are associations between resistin levels and disease severity, we measured serum resistin levels in 102 patients with anti-acetylcholine receptor antibody-positive MG (AChR-MG). We further analyzed associations between serum resistin levels and clinical variables in patients with MG. Our findings demonstrate that serum resistin levels are elevated in patients with AChR-generalized MG and AChR-MG with thymoma and are correlated with disease severity. Resistin has potential as a useful serum biomarker for inflammation in AChR-MG.

  5. Intracellular activity of tedizolid phosphate and ACH-702 versus Mycobacterium tuberculosis infected macrophages

    PubMed Central

    2014-01-01

    Background Due to the emergency of multidrug-resistant strains of Mycobacterium tuberculosis, is necessary the evaluation of new compounds. Findings Tedizolid, a novel oxazolidinone, and ACH-702, a new isothiazoloquinolone, were tested against M. tuberculosis infected THP-1 macrophages. These two compounds significantly decreased the number of intracellular mycobacteria at 0.25X, 1X, 4X and 16X the MIC value. The drugs were tested either in nanoparticules or in free solution. Conclusion Tedizolid and ACH-702 have a good intracellular killing activity comparable to that of rifampin or moxifloxacin. PMID:24708819

  6. Varenicline enhances oxidized LDL uptake by increasing expression of LOX-1 and CD36 scavenger receptors through α7 nAChR in macrophages.

    PubMed

    Kanaoka, Yuki; Koga, Mitsuhisa; Sugiyama, Keita; Ohishi, Kaoru; Kataoka, Yasufumi; Yamauchi, Atsushi

    2017-04-01

    Varenicline is a widely used and effective drug for smoking cessation. It is a partial agonist of the α4β2 nicotinic acetylcholine receptor (nAChR) and full agonist of α7 nAChR. We have reported that varenicline aggravates formation of atherosclerotic plaques through α7 nAChR in apolipoprotein E knockout mice. However, little is known about its effects on macrophages in atherosclerotic plaques. Here, we ascertained whether varenicline promotes oxidized low-density lipoprotein (oxLDL) uptake in mouse peritoneal macrophages in vitro and clarified its mechanism. We investigated the effects of varenicline (1-10μM) on expression of scavenger receptors (lectin-like oxidized LDL receptor-1 (LOX-1), cluster of differentiation (CD) 36 and scavenger receptor class A (SR-A)) in RAW264.7 cells. Expression of protein and mRNA was determined by western blotting and real-time quantitative reverse transcription-polymerase chain reaction, respectively. Effects of varenicline (10μM) on oxLDL uptake were examined by counting the number of macrophages stained with oil red O and hematoxylin. Varenicline significantly increased expression of the protein and mRNA of LOX-1 and CD36, but not SR-A, in RAW264.7 cells, and increased oxLDL uptake in macrophages. These effects of varenicline were blocked significantly by an α7 nAChR antagonist, methyllycaconitine (MLA) (50nM), but not by an α4β2 nAChR antagonist, dihydro-β-erythroidine hydrobromide (DHβE) (1μM). These data suggest that varenicline promotes oxLDL uptake by upregulating expression of LOX-1 and CD36 through α7 nAChR in macrophages. We found that varenicline significantly activated extracellular signal-regulated kinase 1/2 (ERK1/2) and nuclear factor-kappa B (NF-κB) signaling pathways in RAW264.7 cells. This activation was blocked by MLA but not DHβE. Therefore, ERK1/2-NF-κB signaling pathway is highly likely to be responsible for varenicline-induced upregulation of LOX-1 and CD36 expression through α7 nAChR in

  7. Interactions of AChE with Aβ Aggregates in Alzheimer's Brain: Therapeutic Relevance of IDN 5706.

    PubMed

    Carvajal, Francisco J; Inestrosa, Nibaldo C

    2011-01-01

    Acetylcholinesterase (AChE; EC 3.1.1.7) plays a crucial role in the rapid hydrolysis of the neurotransmitter acetylcholine, in the central and peripheral nervous system and might also participate in non-cholinergic mechanism related to neurodegenerative diseases. Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive deterioration of cognitive abilities, amyloid-β (Aβ) peptide accumulation and synaptic alterations. We have previously shown that AChE is able to accelerate the Aβ peptide assembly into Alzheimer-type aggregates increasing its neurotoxicity. Furthermore, AChE activity is altered in brain and blood of Alzheimer's patients. The enzyme associated to amyloid plaques changes its enzymatic and pharmacological properties, as well as, increases its resistant to low pH, inhibitors and excess of substrate. Here, we reviewed the effects of IDN 5706, a hyperforin derivative that has potential preventive effects on the development of AD. Our results show that treatment with IDN 5706 for 10 weeks increases brain AChE activity in 7-month-old double transgenic mice (APP(SWE)-PS1) and decreases the content of AChE associated with different types of amyloid plaques in this Alzheimer's model. We concluded that early treatment with IDN 5706 decreases AChE-Aβ interaction and this effect might be of therapeutic interest in the treatment of AD.

  8. Natural AChE Inhibitors from Plants and their Contribution to Alzheimer’s Disease Therapy

    PubMed Central

    Murray, Ana Paula; Faraoni, María Belén; Castro, María Julia; Alza, Natalia Paola; Cavallaro, Valeria

    2013-01-01

    As acetylcholinesterase (AChE) inhibitors are an important therapeutic strategy in Alzheimer’s disease, efforts are being made in search of new molecules with anti-AChE activity. The fact that naturally-occurring compounds from plants are considered to be a potential source of new inhibitors has led to the discovery of an important number of secondary metabolites and plant extracts with the ability of inhibiting the enzyme AChE, which, according to the cholinergic hypothesis, increases the levels of the neurotransmitter acetylcholine in the brain, thus improving cholinergic functions in patients with Alzheimer’s disease and alleviating the symptoms of this neurological disorder. This review summarizes a total of 128 studies which correspond to the most relevant research work published during 2006-2012 (1st semester) on plant-derived compounds, plant extracts and essential oils found to elicit AChE inhibition. PMID:24381530

  9. Salivary Acetylcholinesterase Activity Is Increased in Parkinson's Disease: A Potential Marker of Parasympathetic Dysfunction

    PubMed Central

    Fedorova, Tatyana; Knudsen, Cindy Soendersoe; Mouridsen, Kim; Nexo, Ebba; Borghammer, Per

    2015-01-01

    Introduction. Decreased salivary flow and xerostomia are frequent findings in Parkinson's disease (PD), possibly caused by alterations in the parasympathetic tonus. Here we explore salivary acetylcholinesterase (AChE) activity as a potential biomarker in PD. Methods. We measured salivary flow, AChE activity, and total protein concentration in 30 PD patients and 49 healthy controls. We also performed exploratory correlation analyses with disease duration, motor symptom severity, autonomic complaints, and other nonmotor symptoms. Results. PD patients displayed significantly decreased salivary flow rate, significantly increased salivary AChE activity, and total protein concentration. Importantly, the AChE activity/total protein ratio was significantly increased in PD patients, suggesting that increased AChE activity cannot be explained solely by upconcentration of saliva. The Unified PD Rating Scale (UPDRS) score displayed significant correlation with total salivary protein (P = 0.002) and near-significant correlation with salivary flow (P = 0.07). Color vision test scores were also significantly correlated with AChE activity (P = 0.04) and total protein levels (P = 0.002). Conclusion. Salivary AChE activity is increased in PD patients compared to healthy controls. Future studies are needed to elucidate whether this parameter reflects the extent of neuronal damage and parasympathetic denervation in the salivary glands of PD patients. PMID:25767737

  10. Mechanism of interaction of novel uncharged, centrally active reactivators with OP-hAChE conjugates.

    PubMed

    Radić, Zoran; Sit, Rakesh K; Garcia, Edzna; Zhang, Limin; Berend, Suzana; Kovarik, Zrinka; Amitai, Gabriel; Fokin, Valery V; Barry Sharpless, K; Taylor, Palmer

    2013-03-25

    A library of more than 200 novel uncharged oxime reactivators was used to select and refine lead reactivators of human acetylcholinesterase (hAChE) covalently conjugated with sarin, cyclosarin, VX, paraoxon and tabun. N-substituted 2-hydroxyiminoacetamido alkylamines were identified as best reactivators and reactivation kinetics of the lead oximes, RS41A and RS194B, were analyzed in detail. Compared to reference pyridinium reactivators, 2PAM and MMB4, molecular recognition of RS41A reflected in its Kox constant was compromised by an order of magnitude on average for different OP-hAChE conjugates, without significant differences in the first order maximal phosphorylation rate constant k(2). Systematic structural modifications of the RS41A lead resulted in several-fold improvement with reactivator, RS194B. Kinetic analysis indicated K(ox) reduction for RS194B as the main kinetic constant leading to efficient reactivation. Subtle structural modifications of RS194B were used to identify essential determinants for efficient reactivation. Computational molecular modeling of RS41A and RS194B interactions with VX inhibited hAChE, bound reversibly in Michaelis type complex and covalently in the pentacoordinate reaction intermediate suggests that the faster reactivation reaction is a consequence of a tighter RS194B interactions with hAChE peripheral site (PAS) residues, in particular with D74, resulting in lower interaction energies for formation of both the binding and reactivation states. Desirable in vitro reactivation properties of RS194B, when coupled with its in vivo pharmacokinetics and disposition in the body, reveal the potential of this oxime design as promising centrally and peripherally active antidotes for OP toxicity.

  11. Nicotine activates YAP1 through nAChRs mediated signaling in esophageal squamous cell cancer (ESCC).

    PubMed

    Zhao, Yue; Zhou, Wei; Xue, Liyan; Zhang, Weimin; Zhan, Qimin

    2014-01-01

    Cigarette smoking is an established risk factor for esophageal cancers. Yes-associated protein 1 (YAP1), the key transcription factor of the mammalian Hippo pathway, has been reported to be an oncogenic factor for many cancers. In this study, we find nicotine administration can induce nuclear translocation and activation of YAP1 in ESCC. Consistently, we observed nuclear translocation and activation of YAP1 by knockdown of CHRNA3, which is a negative regulator of nicotine signaling in bronchial and esophageal cancer cells. Nicotine administration or CHRNA3 depletion substantially increased proliferation and migration in esophageal cancer cells. Interestingly, we find that YAP1 physically interacts with nAChRs, and nAChRs-signaling dissociates YAP1 from its negative regulatory complex composed with α-catenin, β-catenin and 14-3-3 in the cytoplasm, leading to upregulation and nuclear translocation of YAP1. This process likely requires PKC activation, as PKC specific inhibitor Enzastaurin can block nicotine induced YAP1 activation. In addition, we find nicotine signaling also inhibits the interaction of YAP1 with P63, which contributes to the inhibitory effect of nicotine on apoptosis. Using immunohistochemistry analysis we observed upregulation of YAP1 in a significant portion of esophageal cancer samples. Consistently, we have found a significant association between YAP1 upregulation and cigarette smoking in the clinical esophageal cancer samples. Together, these findings suggest that the nicotine activated nAChRs signaling pathway which further activates YAP1 plays an important role in the development of esophageal cancer, and this mechanism may be of a general significance for the carcinogenesis of smoking related cancers.

  12. The pharmacological activity of nicotine and nornicotine on nAChRs subtypes: relevance to nicotine dependence and drug discovery.

    PubMed

    Papke, Roger L; Dwoskin, Linda P; Crooks, Peter A

    2007-04-01

    Cigarette smoking and other forms of tobacco use deliver an array of pharmacologically active alkaloids, including nicotine and ultimately various metabolites of these substances. While nornicotine is a significant component in tobacco as well as a minor systemic metabolite of nicotine, nornicotine appears to be N-demethylated locally in the brain where it accumulates at relatively high levels after chronic nicotine administration. We have now examined the effects of nornicotine on specific combinations of neuronal nicotinic acetylcholine receptor (nAChR) subunits expressed in Xenopus oocytes and compared these responses to those evoked by acetylcholine and nicotine. Of the nAChR subtypes studied, we have found that alpha7 receptors are very responsive to nornicotine (EC50 approximately 17 micromol/L I(max) 50%, compared with acetylcholine (ACh)). nAChRs containing the ligand-binding domain of the alpha6 subunits (in the form of an alpha6/alpha3 chimera) are also strongly responsive to nornicotine (EC50 approximately 4 micromol/L I(max) 50%, compared with ACh). Alpha7-type nAChRs have been suggested to be potential therapeutic targets for Alzheimer's disease, schizophrenia and possibly other pathologies. nAChRs containing alpha6 subunits have been suggested to have a role in nicotine-evoked dopamine release. Thus, understanding the actions of nornicotine in the brain may have significance for both emerging therapeutics and the management of nicotine dependence.

  13. In Vitro Activity of a New Isothiazoloquinolone, ACH-702, against Mycobacterium tuberculosis and Other Mycobacteria▿

    PubMed Central

    Molina-Torres, Carmen A.; Ocampo-Candiani, Jorge; Rendón, Adrian; Pucci, Michael J.; Vera-Cabrera, Lucio

    2010-01-01

    In this work, we describe the activity of ACH-702 against clinical isolates of Mycobacterium tuberculosis and six different nontuberculous mycobacteria. The MIC50 and MIC90 of both susceptible and drug-resistant M. tuberculosis strains tested were 0.0625 and 0.125 μg/ml, respectively. The MIC50 and MIC90 values for Mycobacterium fortuitum isolates were 0.0625 μg/ml in both cases; Mycobacterium avium complex isolates showed MIC50 and MIC90 values of 0.25 and 4 μg/ml, respectively. PMID:20231398

  14. In Vitro Anti-AChE, Anti-BuChE, and Antioxidant Activity of 12 Extracts of Eleutherococcus Species

    PubMed Central

    2016-01-01

    Neurodegenerative diseases are one of the most occurring diseases in developed and developing countries. The aim of this work focused on the screening of the natural inhibitors of AChE and BuChE and antioxidants in Eleutherococcus species. We found that the ethanol extracts of E. setchuenensis and E. sessiliflorus showed the strongest inhibition towards AChE (IC50: 0.3 and 0.3 mg/mL, resp.). Among chloroform extracts, the most active appeared to be E. gracilistylus (IC50: 0.37 mg/mL). In turn, the ethanol extract of E. henryi inhibited the strongest BuChE with IC50 value of 0.13 mg/mL. Among chloroform extracts, E. gracilistylus, E. setchuenensis, and E. sessiliflorus appeared to be the strongest with IC50 values of 0.12, 0.18, and 0.19 mg/mL. HPTLC screening confirmed the presence of inhibitors in extracts. All extracts exhibited anti-DPPH⁎ activity and single antioxidants have been identified. To the best of our knowledge, no information was available on this activity of compounds in Eleutherococcus. These studies provide a biochemical basis for the regulation of AChE and BuChE and encourage us to continue isolation of active compounds. PMID:27803761

  15. In Vitro Anti-AChE, Anti-BuChE, and Antioxidant Activity of 12 Extracts of Eleutherococcus Species.

    PubMed

    Załuski, Daniel; Kuźniewski, Rafał

    2016-01-01

    Neurodegenerative diseases are one of the most occurring diseases in developed and developing countries. The aim of this work focused on the screening of the natural inhibitors of AChE and BuChE and antioxidants in Eleutherococcus species. We found that the ethanol extracts of E. setchuenensis and E. sessiliflorus showed the strongest inhibition towards AChE (IC50: 0.3 and 0.3 mg/mL, resp.). Among chloroform extracts, the most active appeared to be E. gracilistylus (IC50: 0.37 mg/mL). In turn, the ethanol extract of E. henryi inhibited the strongest BuChE with IC50 value of 0.13 mg/mL. Among chloroform extracts, E. gracilistylus, E. setchuenensis, and E. sessiliflorus appeared to be the strongest with IC50 values of 0.12, 0.18, and 0.19 mg/mL. HPTLC screening confirmed the presence of inhibitors in extracts. All extracts exhibited anti-DPPH(⁎) activity and single antioxidants have been identified. To the best of our knowledge, no information was available on this activity of compounds in Eleutherococcus. These studies provide a biochemical basis for the regulation of AChE and BuChE and encourage us to continue isolation of active compounds.

  16. Endogenous activation of nAChRs and NMDA receptors contributes to the excitability of CA1 stratum radiatum interneurons in rat hippocampal slices: effects of kynurenic acid.

    PubMed

    Alkondon, Manickavasagom; Pereira, Edna F R; Albuquerque, Edson X

    2011-10-15

    CA1 stratum radiatum interneurons (SRIs) express α7 nicotinic receptors (nAChRs) and receive inputs from glutamatergic neurons/axons that express α3β4β2 nAChRs. To test the hypothesis that endogenously active α7 and/or α3β4β2 nAChRs control the excitability of CA1 SRIs in the rat hippocampus, we examined the effects of selective receptor antagonists on spontaneous fast current transients (CTs) recorded from these interneurons under cell-attached configuration. The frequency of CTs, which represent action potentials, increased in the absence of extracellular Mg(2+) and decreased in the presence of the α3β4β2 nAChR antagonist mecamylamine (3 μM) or the NMDA receptor antagonist APV (50 μM). However, it was unaffected by the α7 nAChR antagonist MLA (10 nM) or the AMPA receptor antagonist CNQX (10 μM). Thus, in addition to synaptically and tonically activated NMDA receptors, α3β4β2 nAChRs that are present on glutamatergic axons/neurons synapsing onto SRIs and are activated by basal levels of acetylcholine contribute to the maintenance of the excitability of these interneurons. Kynurenic acid (KYNA), an astrocyte-derived kynurenine metabolite whose levels are increased in the brains of patients with schizophrenia, also controls the excitability of SRIs. At high micromolar concentrations, KYNA, acting primarily as an NMDA receptor antagonist, decreased the CT frequency recorded from the interneurons. At 2 μM, KYNA reduced the CA1 SRI excitability via mechanisms independent of NMDA receptor block. KYNA-induced reduction of excitability of SRIs may contribute to sensory gating deficits that have been attributed to deficient hippocampal GABAergic transmission and high levels of KYNA in the brain of patients with schizophrenia.

  17. Muscle aches

    MedlinePlus

    ... common cause of muscle aches and pain is fibromyalgia , a condition that causes tenderness in your muscles ... imbalance, such as too little potassium or calcium Fibromyalgia Infections, including the flu, Lyme disease , malaria , muscle ...

  18. Measurement of p-nitrophenyl acetate esterase activity (EA), total antioxidant capacity (TAC), total oxidant status (TOS) and acetylcholinesterase (AChE) in gills and digestive gland of Mytilus galloprovincialis exposed to binary mixtures of Pb, Cd and Cu.

    PubMed

    Franco-Martinez, Lorena; Romero, Diego; García-Navarro, José A; Tecles, Fernando; Teles, Mariana; Tvarijonaviciute, Asta

    2016-12-01

    The aims of the present work were (1) to evaluate oxidative stress biomarkers and AChE in two tissues of wild mussel (Mytilus galloprovincialis) of high biochemical activity and accumulation capacity (gills and digestive gland) and (2) to study the behaviour of these biomarkers in presence of heavy metals. For this, EA, TOS, TAC and AChE were measured in tissues of mussels exposed to binary combination of Pb, Cd and Cu. Mussels (n = 36) were exposed to one of the binary mixtures of Pb (1000 μg L(-1)), Cd (100 μg L(-1)) and Cu (100 μg L(-1)) for 7 days, under controlled conditions. Gills and digestive gland were extracted and frozen at -80 °C until analysis. The automatic methods employed for the measurement of EA, TAC, TOS and AChE in M. galloprovincialis revealed higher levels of these biomarkers in digestive gland than gills. Study results suggest that gills would be the tissue of election for study oxidative stress markers, whereas digestive tissue should be selected for AChE measurements in case of evaluation of combined metal toxicity in mussels.

  19. Analysis of AchE and LDH in mollusc, Lamellidens marginalis after exposure to chlorpyrifos.

    PubMed

    Amanullah, B; Stalin, A; Prabu, P; Dhanapal, S

    2010-07-01

    The enzymes Acetylcholinesterase (AchE) and Lactatedehydrogenase (LDH) are used as biological markers in the present study. Enzymes are highly sensitive and used to evaluate the biological effects of organophosphate pesticide chlorpyrifos in freshwater mussel Lamellidens marginalis. The test organisms were exposed to sub-lethal concentration (5 ppm) of chlorpyrifos for 30 days and allowed to recover for seven days. A distinct reduction of the enzyme AchE (34 +/- 3.3 U l(-1)) was found in the treated hepatopancreas. A significant increase in LDH activity in gill, hepatopancreas and muscle was observed. There was a significant recovery in AchE and LDH in the different tissues, after seven days recovery period.. Hence, the changes in the enzymes are found as the best biomarkering tool to evaluate the effect of organophosphate pesticide chlorpyrifos on the aquatic biota.

  20. Potentiation by tonic A2a-adenosine receptor activation of CGRP-facilitated [3H]-ACh release from rat motor nerve endings.

    PubMed Central

    Correia-de-Sá, P.; Ribeiro, J. A.

    1994-01-01

    1. The effect of calcitonin gene-related peptide (CGRP) on [3H]-acetylcholine ([3H]-ACh) release from motor nerve endings and its interaction with presynaptic facilitatory A2a-adenosine and nicotinic acetylcholine receptors was studied on rat phrenic nerve-hemidiaphragm preparations loaded with [3H]-choline. 2. CGRP (100-400 nM) increased electrically evoked [3H]-ACh release from phrenic nerve endings in a concentration-dependent manner. 3. The magnitude of CGRP excitation increased with the increase of the stimulation pulse duration from 40 microseconds to 1 ms, keeping the frequency, the amplitude and the train length constants. With 1 ms pulses, the evoked [3H]-ACh release was more intense than with 40 microseconds pulse duration. 4. Both the nicotinic acetylcholine receptor agonist, 1,1-dimethyl-4-phenylpiperazinium, and the A2a adenosine receptor agonist, CGS 21680C, increased evoked [3H]-ACh release, but only CGS 21680C potentiated the facilitatory effect of CGRP. This potentiation was prevented by the A2a adenosine receptor antagonist, PD 115,199. 5. Adenosine deaminase prevented the excitatory effect of CGRP (400 nM) on [3H]-ACh release. This effect was reversed by the non-hydrolysable A2a-adenosine receptor agonist, CGS 21680C. 6. The nicotinic antagonist, tubocurarine, did not significantly change, whereas the A2-adenosine receptor antagonist, PD 115,199, blocked the CGRP facilitation. The A1-adenosine receptor antagonist, 1,3-dipropyl-8-cyclopentylxanthine, potentiated the CGRP excitatory effect. 7. The results suggest that the facilitatory effect of CGRP on evoked [3H]-ACh release from rat phrenic motor nerve endings depends on the presence of endogenous adenosine which tonically activates A2a-adenosine receptors.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8004402

  1. Interactions of AChE with Aβ Aggregates in Alzheimer’s Brain: Therapeutic Relevance of IDN 5706

    PubMed Central

    Carvajal, Francisco J.; Inestrosa, Nibaldo C.

    2011-01-01

    Acetylcholinesterase (AChE; EC 3.1.1.7) plays a crucial role in the rapid hydrolysis of the neurotransmitter acetylcholine, in the central and peripheral nervous system and might also participate in non-cholinergic mechanism related to neurodegenerative diseases. Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by a progressive deterioration of cognitive abilities, amyloid-β (Aβ) peptide accumulation and synaptic alterations. We have previously shown that AChE is able to accelerate the Aβ peptide assembly into Alzheimer-type aggregates increasing its neurotoxicity. Furthermore, AChE activity is altered in brain and blood of Alzheimer’s patients. The enzyme associated to amyloid plaques changes its enzymatic and pharmacological properties, as well as, increases its resistant to low pH, inhibitors and excess of substrate. Here, we reviewed the effects of IDN 5706, a hyperforin derivative that has potential preventive effects on the development of AD. Our results show that treatment with IDN 5706 for 10 weeks increases brain AChE activity in 7-month-old double transgenic mice (APPSWE–PS1) and decreases the content of AChE associated with different types of amyloid plaques in this Alzheimer’s model. We concluded that early treatment with IDN 5706 decreases AChE–Aβ interaction and this effect might be of therapeutic interest in the treatment of AD. PMID:21949501

  2. Does time difference of the acetylcholinesterase (AChE) inhibition in different tissues exist? A case study of zebra fish (Danio rerio) exposed to cadmium chloride and deltamethrin.

    PubMed

    Zhang, Tingting; Yang, Meiyi; Pan, Hongwei; Li, Shangge; Ren, Baigang; Ren, Zongming; Xing, Na; Qi, Luhuizi; Ren, Qing; Xu, Shiguo; Song, Jie; Ma, Jingchun

    2017-02-01

    In order to illustrate time difference in toxic effects of cadmium chloride (CdCl2) and deltamethrin (DM), AChE activities were measured in different tissues, liver, muscle, brain, and gill, of Zebra fish (Danio rerio) across different concentrations in this research. The average AChE activity decreased comparing to 0.0 TU with DM (82.81% in 0.1 TU, 56.14% in 1.0 TU and 44.68% in 2.0 TU) and with CdCl2 (74.68% in 0.1 TU, 52.05% in 1.0 TU and 50.14% in 2.0 TU) showed an overall decrease with the increase of exposure concentrations. According to Self-Organizing Map (SOM), the AChE activities were characterized in relation with experimental conditions, showing an inverse relationship with exposure time. As the exposure time was longer, the AChE activities were correspondingly lower. The AChE inhibition showed time delay in sublethal treatments (0.1 TU) in different tissues: the AChE was first inhibited in brain by chemicals followed by gill, muscle and liver (brain > gill > muscle > liver). The AChE activity was almost inhibited synchronously in higher environmental stress (1.0 TU and 2.0 TU). As the AChE inhibition can induce abnormal of behavior movement, these results will be helpful to the mechanism of stepwise behavior responses according to the time difference in different tissues rather than the whole body AChE activity.

  3. Understanding the conformational flexibility and electrostatic properties of curcumin in the active site of rhAChE via molecular docking, molecular dynamics, and charge density analysis.

    PubMed

    Saravanan, Kandasamy; Kalaiarasi, Chinnasamy; Kumaradhas, Poomani

    2017-01-04

    Acetylcholinesterase (AChE) is an important enzyme responsible for Alzheimer's disease, as per report, keto-enol form of curcumin inhibits this enzyme. The present study aims to understand the binding mechanism of keto-enol curcumin with the recombinant human Acetylcholinesterase (rhAChE) from its conformational flexibility, intermolecular interactions, charge density distribution, and the electrostatic properties at the active site of rhAChE. To accomplish this, a molecular docking analysis of curcumin with the rhAChE was performed, which gives the structure and conformation of curcumin in the active site of rhAChE. Further, the charge density distribution and the electrostatic properties of curcumin molecule (lifted from the active site of rhAChE) were determined from the high level density functional theory (DFT) calculations coupled with the charge density analysis. On the other hand, the curcumin molecule was optimized (gas phase) using DFT method and further, the structure and charge density analysis were also carried out. On comparing the conformation, charge density distribution and the electrostatic potential of the active site form of curcumin with the corresponding gas phase form reveals that the above said properties are significantly altered when curcumin is present in the active site of rhAChE. The conformational stability and the interaction of curcumin in the active site are also studied using molecular dynamics simulation, which shows a large variation in the conformational geometry of curcumin as well as the intermolecular interactions.

  4. Activation of α7nAChR Promotes Diabetic Wound Healing by Suppressing AGE-Induced TNF-α Production.

    PubMed

    Dong, Miao-Wu; Li, Ming; Chen, Jie; Fu, Tong-Tong; Lin, Ke-Zhi; Ye, Guang-Hua; Han, Jun-Ge; Feng, Xiang-Ping; Li, Xing-Biao; Yu, Lin-Sheng; Fan, Yan-Yan

    2016-04-01

    Diabetes frequently presents accumulation of advanced glycation end products (AGEs), which might induce excessive TNF-α production from macrophages to cause impaired wound healing. Recent studies have shown that activation of α7 nicotinic acetylcholine receptor (α7nAChR) on macrophages efficiently suppressed TNF-α synthesis. The aim of this study was to investigate the accumulation of AGEs in the wounds and determine whether PNU282987, an α7nAChR agonist, can improve wound repair by inhibiting AGE-mediated TNF-α production in a streptozotocin (STZ)-induced diabetic mouse model. Animals were assigned into four groups: wounded control group, wounded diabetic group, wounded diabetic group treated intraperitoneally with PNU282987, or wounded diabetic group treated intraperitoneally with vehicle. Compared with the non-diabetic control mice, the diabetic mice exhibited delayed wound healing that was characterized by elevated accumulation of AGEs, increased TNF-α level and macrophage infiltration, and decreased fibroblast number and collagen deposition at the late stage of repair. Besides, macrophages of diabetic wounds showed expression of α7nAChR. During late repair, PNU282987 treatment of diabetic mice significantly reduced the level of TNF-α, accelerated wound healing, and elevated fibroblast number and collagen deposition. To investigate the cellular mechanism of these observations, RAW 264.7 cells, a macrophage cell line, were incubated with AGEs in the presence or absence of PNU282987. TNF-α production from AGE-stimulated macrophages was significantly decreased by PNU282987 in a dose-dependent manner. Furthermore, PNU282987 significantly inhibited AGE-induced nuclear factor-κB (NF-κB) activation and receptor for AGE (RAGE) expression. These results strongly suggest that activating α7nAChR can promote diabetic wound healing by suppressing AGE-induced TNF-α production, which may be closely associated with the blockage of NF-κB activation in macrophages.

  5. AChE inhibition: one dominant factor for swimming behavior changes of Daphnia magna under DDVP exposure.

    PubMed

    Ren, Zongming; Zhang, Xu; Wang, Xiaoguang; Qi, Pingping; Zhang, Biao; Zeng, Yang; Fu, Rongshu; Miao, Mingsheng

    2015-02-01

    As a key enzyme that hydrolyzes the neurotransmitter acetylcholine in cholinergic synapses of both vertebrates and invertebrates, acetylcholinesterase (AChE) is strongly inhibited by organophosphates. AChE inhibition may induce the decrease of swimming ability. According to previous research, swimming behavior of different aquatic organisms could be affected by different chemicals, and there is a shortage of research on direct correlation analysis between swimming behavior and biochemical indicators. Therefore, swimming behavior and whole-body AChE activity of Daphnia magna under dichlorvos (DDVP) exposure were identified in order to clarify the relationship between behavioral responses and AChE inhibition in this study. In the beginning, AChE activity was similar in all treatments with the control. During all exposures, the tendency of AChE activity inhibition was the same as the behavioral responses of D. magna. The AChE activity of individuals without movement would decrease to about zero in several minutes. The correlation analysis between swimming behavior of D. magna and AChE activity showed that the stepwise behavioral response was mainly decided by AChE activity. All of these results suggested that the toxicity characteristics of DDVP as an inhibitor of AChE on the swimming behavior of organisms were the same, and the AChE activity inhibition could induce loss of the nerve conduction ability, causing hyperactivity, loss of coordination, convulsions, paralysis and other kinds of behavioral changes, which was illustrated by the stepwise behavioral responses under different environmental stresses.

  6. Effect of metoclopramide and ranitidine on the inhibition of human AChE by VX in vitro.

    PubMed

    Bartling, A; Thiermann, H; Szinicz, L; Worek, F

    2005-01-01

    The repeated misuse of highly toxic organophosphorus-type (OP) chemical warfare agents ('nerve agents') emphasizes the necessity for the development of effective medical countermeasures. The standard treatment with atropine and acetylcholinesterase (AChE) reactivators ('oximes') is considered to be ineffective with certain nerve agents due to low oxime efficacy. Therefore, pretreatment with carbamate-type compounds, e.g. pyridostigmine, was recommended to improve antidotal efficacy. Recently, the clinically used reversible AChE inhibitors metoclopramide (MCP) and ranitidine (RAN) were shown to exhibit some protective effect against the OP pesticide paraoxon in vitro and in vivo. The present study was undertaken to investigate a potential protective effect of MCP and RAN against inhibition of human AChE by the nerve agent VX (O-ethyl S-[2-(diisopropylamino)ethyl)methylphosphonothioate). Hemoglobin-free human erythrocyte membranes were incubated with various, human relevant MCP (0.5-2 microm) and RAN (0.5-5 microm) concentrations starting 1 min before addition of VX (1-40 nm). Both compounds failed to increase VX IC(50) values. In addition, human AChE was incubated with higher than human relevant therapeutic concentrations of MCP (1 microm-1 mm) and RAN (1 microm-2.0 mm) and inhibited by 40 nm VX. At concentrations higher than 100 microm MCP and RAN caused a concentration dependent increase of residual AChE activity 15 min after addition of VX. These data indicate that MCP and RAN may be ineffective in protecting human AChE against inhibition by the nerve agent VX at human relevant doses.

  7. Cotinine exposure increases Fallopian tube PROKR1 expression via nicotinic AChRalpha-7: a potential mechanism explaining the link between smoking and tubal ectopic pregnancy.

    PubMed

    Shaw, Julie L V; Oliver, Elizabeth; Lee, Kai-Fai; Entrican, Gary; Jabbour, Henry N; Critchley, Hilary O D; Horne, Andrew W

    2010-11-01

    Tubal ectopic pregnancy (EP) is the most common cause of maternal mortality in the first trimester of pregnancy; however, its etiology is uncertain. In EP, embryo retention within the Fallopian tube (FT) is thought to be due to impaired smooth muscle contractility (SMC) and alterations in the tubal microenvironment. Smoking is a major risk factor for EP. FTs from women with EP exhibit altered prokineticin receptor-1 (PROKR1) expression, the receptor for prokineticins (PROK). PROK1 is angiogenic, regulates SMC, and is involved in intrauterine implantation. We hypothesized that smoking predisposes women to EP by altering tubal PROKR1 expression. Sera/FT were collected at hysterectomy (n=21). Serum levels of the smoking metabolite, cotinine, were measured by enzyme-linked immunosorbent assay. FTs were analyzed by q-RT-PCR, immunohistochemistry, and Western blotting for expression of PROKR1 and the predicted cotinine receptor, nicotinic acetylcholine receptor α-7 (AChRα-7). FT explants (n=4) and oviductal epithelial cells (cell line OE-E6/E7) were treated with cotinine and an nAChRα-7 antagonist. PROKR1 transcription was higher in FTs from smokers (P<0.01). nAChRα-7 expression was demonstrated in FT epithelium. Cotinine treatment of FT explants and OE-E6/E7 cells increased PROKR1 expression (P<0.05), which was negated by cotreatment with nAChRα-7 antagonist. Smoking targets human FTs via nAChRα-7 to increase tubal PROKR1, leading to alterations in the tubal microenvironment that could predispose to EP.

  8. Activation of Functional α7-Containing nAChRs in Hippocampal CA1 Pyramidal Neurons by Physiological Levels of Choline in the Presence of PNU-120596

    PubMed Central

    Kalappa, Bopanna I.; Gusev, Alexander G.; Uteshev, Victor V.

    2010-01-01

    Background The level of expression of functional α7-containing nicotinic acetylcholine receptors (nAChRs) in hippocampal CA1 pyramidal neurons is believed to be very low compared to hippocampal CA1 interneurons, and for many years this expression was largely overlooked. However, high densities of expression of functional α7-containing nAChRs in CA1 pyramidal neurons may not be necessary for triggering important cellular and network functions, especially if activation of α7-containing nAChRs occurs in the presence of positive allosteric modulators such as PNU-120596. Methodology/Principal Findings An approach previously developed for α7-containing nAChRs expressed in tuberomammillary neurons was applied to investigate functional CA1 pyramidal α7-containing nAChRs using rat coronal hippocampal slices and patch-clamp electrophysiology. The majority (∼71%) of tested CA1 pyramidal neurons expressed low densities of functional α7-containing nAChRs as evidenced by small whole-cell responses to choline, a selective endogenous agonist of α7 nAChRs. These responses were potentiated by PNU-120596, a novel positive allosteric modulator of α7 nAChRs. The density of functional α7-containing nAChRs expressed in CA1 pyramidal neurons (and thus, the normalized net effect of activation, i.e., response net charge per unit of membrane capacitance per unit of time) was estimated to be ∼5% of the density observed in CA1 interneurons. The results of this study demonstrate that despite low levels of expression of functional pyramidal α7-containing nAChRs, physiological levels of choline (∼10 µM) are sufficient to activate these receptors and transiently depolarize and even excite CA1 pyramidal neurons in the presence of PNU-120596. The observed effects are possible because in the presence of 10 µM choline and 1–5 µM PNU-120596, a single opening of an individual pyramidal α7-containing nAChR ion channel appears to transiently depolarize (∼4 mV) the entire pyramidal

  9. Sperm Epidermal Growth Factor Receptor (EGFR) Mediates α7 Acetylcholine Receptor (AChR) Activation to Promote Fertilization

    PubMed Central

    Jaldety, Yael; Glick, Yair; Orr-Urtreger, Avi; Ickowicz, Debby; Gerber, Doron; Breitbart, Haim

    2012-01-01

    To attain fertilization the spermatozoon binds to the egg zona pellucida (ZP) via sperm receptor(s) and undergoes an acrosome reaction (AR). Several sperm receptors have been described in the literature; however, the identity of this receptor is not yet certain. In this study, we suggest that the α7 nicotinic acetylcholine receptor (α7nAChR) might be a sperm receptor activated by ZP to induce epidermal growth factor receptor (EGFR)-mediated AR. We found that isolated ZP or α7 agonists induced the AR in sperm from WT but not α7-null spermatozoa, and the induced AR was inhibited by α7 or EGFR antagonists. Moreover, α7-null sperm showed very little binding to the egg, and microfluidic affinity in vitro assay clearly showed that α7nAChR, as well as EGFR, interacted with ZP3. Induction of EGFR activation and the AR by an α7 agonist was inhibited by a Src family kinase (SFK) inhibitor. In conclusion we suggest that activation of α7 by ZP leads to SFK-dependent EGFR activation, Ca2+ influx, and the acrosome reaction. PMID:22577141

  10. Oxidized low density lipoprotein increases acetylcholinesterase activity correlating with reactive oxygen species production.

    PubMed

    Yamchuen, Panit; Aimjongjun, Sathid; Limpeanchob, Nanteetip

    2014-12-01

    Hyperlipidemia, low density lipoproteins (LDL) and their oxidized forms, and oxidative stress are suspected to be a key combination in the onset of AD and acetylcholinesterase (AChE) plays a part in this pathology. The present study aimed to link these parameters using differentiated SH-SY5Y human neuroblastoma cells in culture. Both mildly and fully oxidized human LDL (mox- and fox-LDL), but not native (non-oxidized) LDL were cytotoxic in dose- and time-dependent patterns and this was accompanied by an increased production of intracellular reactive oxygen species (ROS). Oxidized LDL (10-200 μg/mL) augmented AChE activity after 4 and 24h treatments, respectively while the native LDL was without effect. The increased AChE with oxidized LDLs was accompanied by a proportionate increase in intracellular ROS formation (R=0.904). These findings support the notion that oxidized LDLs are cytotoxic and that their action on AChE may reduce central cholinergic transmission in AD and affirm AChE as a continued rational for anticholinesterase therapy but in conjunction with antioxidant/antihyperlipidemic cotreatments.

  11. ARIA/HRG regulates AChR epsilon subunit gene expression at the neuromuscular synapse via activation of phosphatidylinositol 3-kinase and Ras/MAPK pathway

    PubMed Central

    1996-01-01

    AChR-inducing activity (ARIA)/heregulin, a ligand for erbB receptor tyrosine kinases (RTKs), is likely to be one nerve-supplied signal that induces expression of acetylcholine receptor (AChR) genes at the developing neuromuscular junction. Since some RTKs act through Ras and phosphatidylinositol 3-kinase (PI3K), we investigated the role of these pathways in ARIA signaling. Expression of activated Ras or Raf mimicked ARIA-induction of AChR epsilon subunit genes in muscle cells; whereas dominant negative Ras or Raf blocked the effect of ARIA. ARIA rapidly activated erk1 and erk2 and inhibition of both erks also abolished the effect of ARIA. ARIA stimulated association of PI3K with erbB3, expression of an activated PI3K led to ARIA-independent AChR epsilon subunit expression, and inhibition of PI3K abolished the action of ARIA. Thus, synaptic induction of AChR genes requires activation of both Ras/MAPK and PI3K signal transduction pathways. PMID:8707830

  12. Readthrough acetylcholinesterase (AChE-R) and regulated necrosis: pharmacological targets for the regulation of ovarian functions?

    PubMed Central

    Blohberger, J; Kunz, L; Einwang, D; Berg, U; Berg, D; Ojeda, S R; Dissen, G A; Fröhlich, T; Arnold, G J; Soreq, H; Lara, H; Mayerhofer, A

    2015-01-01

    Proliferation, differentiation and death of ovarian cells ensure orderly functioning of the female gonad during the reproductive phase, which ultimately ends with menopause in women. These processes are regulated by several mechanisms, including local signaling via neurotransmitters. Previous studies showed that ovarian non-neuronal endocrine cells produce acetylcholine (ACh), which likely acts as a trophic factor within the ovarian follicle and the corpus luteum via muscarinic ACh receptors. How its actions are restricted was unknown. We identified enzymatically active acetylcholinesterase (AChE) in human ovarian follicular fluid as a product of human granulosa cells. AChE breaks down ACh and thereby attenuates its trophic functions. Blockage of AChE by huperzine A increased the trophic actions as seen in granulosa cells studies. Among ovarian AChE variants, the readthrough isoform AChE-R was identified, which has further, non-enzymatic roles. AChE-R was found in follicular fluid, granulosa and theca cells, as well as luteal cells, implying that such functions occur in vivo. A synthetic AChE-R peptide (ARP) was used to explore such actions and induced in primary, cultured human granulosa cells a caspase-independent form of cell death with a distinct balloon-like morphology and the release of lactate dehydrogenase. The RIPK1 inhibitor necrostatin-1 and the MLKL-blocker necrosulfonamide significantly reduced this form of cell death. Thus a novel non-enzymatic function of AChE-R is to stimulate RIPK1/MLKL-dependent regulated necrosis (necroptosis). The latter complements a cholinergic system in the ovary, which determines life and death of ovarian cells. Necroptosis likely occurs in the primate ovary, as granulosa and luteal cells were immunopositive for phospho-MLKL, and hence necroptosis may contribute to follicular atresia and luteolysis. The results suggest that interference with the enzymatic activities of AChE and/or interference with necroptosis may be novel

  13. Determination of AChE levels and genotoxic effects in farmers occupationally exposed to pesticides.

    PubMed

    Naravaneni, Rambabu; Jamil, Kaiser

    2007-09-01

    Pesticides can cause cytogenetic effects and lower the acetyl cholinesterase (AChE) levels in farmers exposed to pesticides. In this study, 210 farmers exposed to pesticides and 160 non-exposed individuals were enrolled for determining the genotoxicity and AChE levels. The AChE levels were determined in plasma and RBC lysate from blood samples collected from farmers and control subjects. AChE (true and pseudo) estimation done by the colorimetric method revealed that there was a progressive fall in both the RBC and plasma AChE levels in exposed individuals compared to unexposed individuals, which correlated with the severity of exposure (253.5 versus 311.1 and 142.3 versus 152.1; P < 0.001). Cytogenetic studies showed an increase in DNA damage and higher chromosomal aberrations (CAs) in exposed farmers compared to the control subjects (26.13 versus 07.61 and 21.37 versus 1.52; P < 0.001). When comparing the AChE levels with DNA damage and structural CA frequencies, there was a negative linear correlation. Therefore based on these findings, it is concluded that genotoxic biomarkers like CA frequencies, DNA damage data along with AChE levels are important parameters for determining farmer's health who are exposed to pesticides in any situation.

  14. Engineering α4β2 nAChRs with reduced or increased nicotine sensitivity via selective disruption of consensus sites in the M3-M4 cytoplasmic loop of the α4 subunit

    PubMed Central

    Biaggi-Labiosa, Nilza M.; Avilés-Pagán, Emir; Caballero-Rivera, Daniel; Báez-Pagán, Carlos; Lasalde-Dominicci, José A.

    2015-01-01

    The α4β2 neuronal nicotinic acetylcholine receptor (nAChR) plays a crucial role in nicotine addiction. These receptors are known to desensitize and up-regulate after chronic nicotine exposure, but the mechanism remains unknown. Currently, the structure and functional role of the intracellular domains of the nAChR are obscure. To study the effect of subunit phosphorylation on α4β2 nAChR function and expression, eleven residues located in the M3-M4 cytoplasmic loop were mutated to alanine and aspartic acid. Two-electrode voltage clamp and 125I-labeled epibatidine binding assays were performed on Xenopus oocytes to assess agonist activation and receptor expression. When ACh was used as an agonist, a decrease in receptor activation was observed for the majority of the mutations. When nicotine was used as an agonist, four mutations exhibited a statistically significant hypersensitivity to nicotine (S438D, S469A, Y576A, and S589A). Additionally, two mutations (S516D and T536A) that displayed normal activation with ACh displayed remarkable reductions in sensitivity to nicotine. Binding assays revealed a constitutive up-regulation in these two nicotine mutations with reduced nicotine sensitivity. These results suggest that consensus phosphorylation residues in the M3-M4 cytoplasmic loop of the α4 subunit play a crucial role in regulating α4β2 nAChR agonist selectivity and functional expression. Furthermore, these results suggest that disruption of specific interactions at PKC putative consensus sites can render α4β2 nAChRs almost insensitive to nicotine without substantial effects on normal AChR function. Therefore, these PKC consensus sites in the M3-M4 cytoplasmic loop of the α4 nAChR subunit could be a target for smoking cessation drugs. PMID:25957813

  15. Engineering α4β2 nAChRs with reduced or increased nicotine sensitivity via selective disruption of consensus sites in the M3-M4 cytoplasmic loop of the α4 subunit.

    PubMed

    Biaggi-Labiosa, Nilza M; Avilés-Pagán, Emir; Caballero-Rivera, Daniel; Báez-Pagán, Carlos A; Lasalde-Dominicci, José A

    2015-12-01

    The α4β2 neuronal nicotinic acetylcholine receptor (nAChR) plays a crucial role in nicotine addiction. These receptors are known to desensitize and up-regulate after chronic nicotine exposure, but the mechanism remains unknown. Currently, the structure and functional role of the intracellular domains of the nAChR are obscure. To study the effect of subunit phosphorylation on α4β2 nAChR function and expression, eleven residues located in the M3-M4 cytoplasmic loop were mutated to alanine and aspartic acid. Two-electrode voltage clamp and 125I-labeled epibatidine binding assays were performed on Xenopus oocytes to assess agonist activation and receptor expression. When ACh was used as an agonist, a decrease in receptor activation was observed for the majority of the mutations. When nicotine was used as an agonist, four mutations exhibited a statistically significant hypersensitivity to nicotine (S438D, S469A, Y576A, and S589A). Additionally, two mutations (S516D and T536A) that displayed normal activation with ACh displayed remarkable reductions in sensitivity to nicotine. Binding assays revealed a constitutive up-regulation in these two nicotine mutations with reduced nicotine sensitivity. These results suggest that consensus phosphorylation residues in the M3-M4 cytoplasmic loop of the α4 subunit play a crucial role in regulating α4β2 nAChR agonist selectivity and functional expression. Furthermore, these results suggest that disruption of specific interactions at PKC putative consensus sites can render α4β2 nAChRs almost insensitive to nicotine without substantial effects on normal AChR function. Therefore, these PKC consensus sites in the M3-M4 cytoplasmic loop of the α4 nAChR subunit could be a target for smoking cessation drugs.

  16. Identification of novel α4β2-nicotinic acetylcholine receptor (nAChR) agonists based on an isoxazole ether scaffold that demonstrate antidepressant-like activity.

    PubMed

    Yu, Li-Fang; Tückmantel, Werner; Eaton, J Brek; Caldarone, Barbara; Fedolak, Allison; Hanania, Taleen; Brunner, Dani; Lukas, Ronald J; Kozikowski, Alan P

    2012-01-26

    There is considerable evidence to support the hypothesis that the blockade of nAChR is responsible for the antidepressant action of nicotinic ligands. The nicotinic acetylcholine receptor (nAChR) antagonist, mecamylamine, has been shown to be an effective add-on in patients that do not respond to selective serotonin reuptake inhibitors. This suggests that nAChR ligands may address an unmet clinical need by providing relief from depressive symptoms in refractory patients. In this study, a new series of nAChR ligands based on an isoxazole-ether scaffold have been designed and synthesized for binding and functional assays. Preliminary structure-activity relationship (SAR) efforts identified a lead compound 43, which possesses potent antidepressant-like activity (1 mg/kg, IP; 5 mg/kg, PO) in the classical mouse forced swim test. Early stage absorption, distribution, metabolism, excretion, and toxicity (ADME-Tox) studies also suggested favorable drug-like properties, and broad screening toward other common neurotransmitter receptors indicated that compound 43 is highly selective for nAChRs over the other 45 neurotransmitter receptors and transporters tested.

  17. PACAP induces plasticity at autonomic synapses by nAChR-dependent NOS1 activation and AKAP-mediated PKA targeting.

    PubMed

    Jayakar, Selwyn S; Pugh, Phyllis C; Dale, Zack; Starr, Eric R; Cole, Samantha; Margiotta, Joseph F

    2014-11-01

    Pituitary adenylate cyclase-activating polypeptide (PACAP) is a pleiotropic neuropeptide found at synapses throughout the central and autonomic nervous system. We previously found that PACAP engages a selective G-protein coupled receptor (PAC1R) on ciliary ganglion neurons to rapidly enhance quantal acetylcholine (ACh) release from presynaptic terminals via neuronal nitric oxide synthase (NOS1) and cyclic AMP/protein kinase A (PKA) dependent processes. Here, we examined how PACAP stimulates NO production and targets resultant outcomes to synapses. Scavenging extracellular NO blocked PACAP-induced plasticity supporting a retrograde (post- to presynaptic) NO action on ACh release. Live-cell imaging revealed that PACAP stimulates NO production by mechanisms requiring NOS1, PKA and Ca(2+) influx. Ca(2+)-permeable nicotinic ACh receptors composed of α7 subunits (α7-nAChRs) are potentiated by PKA-dependent PACAP/PAC1R signaling and were required for PACAP-induced NO production and synaptic plasticity since both outcomes were drastically reduced following their selective inhibition. Co-precipitation experiments showed that NOS1 associates with α7-nAChRs, many of which are perisynaptic, as well as with heteromeric α3*-nAChRs that generate the bulk of synaptic activity. NOS1-nAChR physical association could facilitate NO production at perisynaptic and adjacent postsynaptic sites to enhance focal ACh release from juxtaposed presynaptic terminals. The synaptic outcomes of PACAP/PAC1R signaling are localized by PKA anchoring proteins (AKAPs). PKA regulatory-subunit overlay assays identified five AKAPs in ganglion lysates, including a prominent neuronal subtype. Moreover, PACAP-induced synaptic plasticity was selectively blocked when PKA regulatory-subunit binding to AKAPs was inhibited. Taken together, our findings indicate that PACAP/PAC1R signaling coordinates nAChR, NOS1 and AKAP activities to induce targeted, retrograde plasticity at autonomic synapses. Such

  18. Active ghrelin levels across time and associations with leptin and anthropometrics in healthy ache Amerindian women of Paraguay.

    PubMed

    Bribiescas, Richard G; Betancourt, Jaime; Torres, Angélica M; Reiches, Meredith

    2008-01-01

    Active (acylated) ghrelin is a peptide hormone secreted primarily by the stomach, positively associated with fasting, orexigenic, and promotes growth hormone secretion. It is therefore important to energy intake management. The objective of this pilot research was to (1) compare active ghrelin with previous measurements of leptin and anthropometrics; (2) assess the consistency of active ghrelin across time in this population; (3) extend our understanding of potential population variation in active ghrelin. Two serum samples separated by 10 days at the same time between meals were collected from healthy Ache women (n = 12, mean age 32.2 +/- 14.0 SD) to determine consistency over time, associations with leptin, and anthropmetric values. Mean active ghrelin was 72.9 +/- 23.0 pg/ml, highly correlated (r(2) = 0.95, P < 0.0001) between collections, and showed no paired mean differences (P < 0.18). There was no significant correlation with leptin, age, or anthropometric measures. Active ghrelin appears to be consistent over time in this population, perhaps reflecting regimented meal schedules and less interpopulation variation compared to leptin.

  19. Acetylsalicylic acid and ascorbic acid combination improves cognition; via antioxidant effect or increased expression of NMDARs and nAChRs?

    PubMed

    Kara, Yusuf; Doguc, Duygu Kumbul; Kulac, Esin; Gultekin, Fatih

    2014-05-01

    Chronic inflammation occurs systematically in the central nervous system during ageing, it has been shown that neuroinflammation plays an important role in the pathogenesis of many neurodegenerative disorders. Aspirin, a nonselective COX inhibitor, as well as ascorbic acid, has been purported to protect cerebral tissue. We investigated the effects of subchronic aspirin and ascorbic acid usage on spatial learning, oxidative stress and expressions of NR2A, NR2B, nAChRα7, α4 and β2. Forty male rats (16-18 months) were divided into 4 groups, namely, control, aspirin-treated, ascorbic acid-treated, aspirin+ascorbic acid-treated groups. Following 10-weeks administration period, rats were trained and tested in the Morris water maze. 8-Hydroxy-2-deoxyguanosine and malondialdehyde were evaluated by ELISA and HPLC, respectively. Receptor expressions were assessed by western blotting of hippocampi. Spatial learning performance improved partially in the aspirin group, but significant improvement was seen in the aspirin+ascorbic acid group (p < 0.05). While 8-hydroxy-2-deoxyguanosine and malondialdehyde levels were significantly decreased, NR2B and nAChRα7 expressions were significantly increased in the aspirin+ascorbic acid group as compared to the control group (p < 0.05). Subchronic treatment with aspirin+ascorbic acid in aged rats was shown to enhance cognitive performance and increase the expressions of several receptors related to learning and memory process.

  20. Structural modifications of 4-aryl-4-oxo-2-aminylbutanamides and their acetyl- and butyrylcholinesterase inhibitory activity. Investigation of AChE-ligand interactions by docking calculations and molecular dynamics simulations.

    PubMed

    Vitorović-Todorović, Maja D; Koukoulitsa, Catherine; Juranić, Ivan O; Mandić, Ljuba M; Drakulić, Branko J

    2014-06-23

    Congeneric set of thirty-eight 4-aryl-4-oxo-2-(N-aryl/cycloalkyl)butanamides has been designed, synthesized and evaluated for acetyl- and butyrylcholinesterase inhibitory activity. Structural variations included cycloalkylamino group attached to C2 position of butanoyl moiety, and variation of amido moiety of molecules. Twelve compounds, mostly piperidino and imidazolo derivatives, inhibited AChE in low micromolar range, and were inactive toward BChE. Several N-methylpiperazino derivatives showed inhibition of BChE in low micromolar or submicromolar concentrations, and were inactive toward AChE. Therefore, the nature of the cycloalkylamino moiety governs the AChE/BChE selectivity profile of compounds. The most active AChE inhibitor showed mixed-type inhibition modality, indicating its binding to free enzyme and to enzyme-substrate complex. Thorough docking calculations of the seven most potent AChE inhibitors from the set, showed that the hydrogen bond can be formed between amide -NH- moiety of compounds and -OH group of Tyr 124. The 10 ns unconstrained molecular dynamic simulation of the AChE-compound 18 complex shows that this interaction is the most persistent. This is, probably, the major anchoring point for the binding.

  1. Inhibition of AChE by malathion and some structurally similar compounds.

    PubMed

    Krstić, Danijela Z; Colović, Mirjana; Kralj, Mojca Bavcon; Franko, Mladen; Krinulović, Katarina; Trebse, Polonca; Vasić, Vesna

    2008-08-01

    Inhibition of bovine erythrocyte acetylcholinesterase (free and immobilized on controlled pore glass) by separate and simultaneous exposure to malathion and malathion transformation products which are generally formed during storage or through natural or photochemical degradation was investigated. Increasing concentrations of malathion, its oxidation product malaoxon, and its isomerisation product isomalathion inhibited free and immobilized AChE in a concentration-dependent manner. KI, the dissociation constant for the initial reversible enzyme inhibitor-complex, and k3, the first order rate constant for the conversion of the reversible complex into the irreversibly inhibited enzyme, were determined from the progressive development of inhibition produced by reaction of native AChE with malathion, malaoxon and isomalathion. KI values of 1.3 x 10(-4) M(-1), 5.6 x 10(-6) M(-1) and 7.2 x 10(-6)M(-1) were obtained for malathion, malaoxon and isomalathion, respectively. The IC50 values for free/immobilized AChE, (3.7 +/- 0.2) x 10(-4) M/(1.6 +/-0.1) x 10(-4), (2.4 +/- 0.3) x 10(-6)/(3.4 +/- 0.1) x 10(-6)M and (3.2 +/- 0.3) x 10(-6) M/(2.7 +/- 0.2) x 10(-6) M, were obtained from the inhibition curves induced by malathion, malaoxon and isomalathion, respectively. However, the products formed due to photoinduced degradation, phosphorodithioic O,O,S-trimethyl ester and O,O-dimethyl thiophosphate, did not noticeably affect enzymatic activity, while diethyl maleate inhibited AChE activity at concentrations > 10mM. Inhibition of acetylcholinesterase increased with the time of exposure to malathion and its inhibiting by-products within the interval from 0 to 5 minutes. Through simultaneous exposure of the enzyme to malaoxon and isomalathion, an additive effect was achieved for lower concentrations of the inhibitors (in the presence of malaoxon/isomalathion at concentrations 2 x 10(-7) M/2 x 10(-7) M, 2 x 10(-7) M/3 x 10(-7)M and 2 x 10(-7) M/4.5 x 109-7) M), while an

  2. Synthesis and structure-activity relationship study of tacrine-based pyrano[2,3-c]pyrazoles targeting AChE/BuChE and 15-LOX.

    PubMed

    Pourabdi, Ladan; Khoobi, Mehdi; Nadri, Hamid; Moradi, Alireza; Moghadam, Farshad Homayouni; Emami, Saeed; Mojtahedi, Mohammad M; Haririan, Ismaeil; Forootanfar, Hamid; Ameri, Alieh; Foroumadi, Alireza; Shafiee, Abbas

    2016-11-10

    A series of tacrine-based pyrazolo[4',3':5,6]pyrano[2,3-b]quinolines and related compounds were designed and synthesized for targeting AChE, BuChE and 15-LOX enzymes in the field of Alzheimer's disease therapy. Most of compounds showed potent activity against cholinesterases and mild potency toward 15-LOX enzyme. In particular, compounds 29, 32 and 40 displayed inhibition at nano-molar level against AChE and BuChE (IC50s = 0.005-0.08 μM), being more potent than reference drug tacrine. Moreover, compound 32 with IC50 value of 31 μM was the most potent compound against 15-LOX. The cytotoxicity assay on HepG2 cells revealed that compounds 29 and 32 showed no significant cytotoxic activity even at concentration of 50 μM. The cytotoxicity of compounds 29 and 32 was significantly less than that of tacrine at higher concentrations.

  3. Activation of muscarinic receptors by ACh release in hippocampal CA1 depolarizes VIP but has varying effects on parvalbumin-expressing basket cells

    PubMed Central

    Bell, L Andrew; Bell, Karen A; McQuiston, A Rory

    2015-01-01

    We investigated the effect of acetylcholine release on mouse hippocampal CA1 perisomatically projecting interneurons. Acetylcholine was optogenetically released in hippocampal slices by expressing the excitatory optogenetic protein oChIEF-tdTomato in medial septum/diagonal band of Broca cholinergic neurons using Cre recombinase-dependent adeno-associated virally mediated transfection. The effect of optogenetically released acetylcholine was assessed on interneurons expressing Cre recombinase in vasoactive intestinal peptide (VIP) or parvalbumin (PV) interneurons using whole cell patch clamp methods. Acetylcholine released onto VIP interneurons that innervate pyramidal neuron perisomatic regions (basket cells, BCs) were depolarized by muscarinic receptors. Although PV BCs were also excited by muscarinic receptor activation, they more frequently responded with hyperpolarizing or biphasic responses. Muscarinic receptor activation resulting from ACh release increased the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) in downstream hippocampal CA1 pyramidal neurons with peak instantaneous frequencies occurring in both the gamma and theta bandwidths. Both PV and VIP BCs contributed to the increased sIPSC frequency in pyramidal neurons and optogenetic suppression of PV or VIP BCs inhibited sIPSCs occurring in the gamma range. Therefore, we propose acetylcholine release in CA1 has a complex effect on CA1 pyramidal neuron output through varying effects on perisomatically projecting interneurons. PMID:25556796

  4. Induction of long-term oscillations in the γ frequency band by nAChR activation in rat hippocampal CA3 area.

    PubMed

    Zhang, X; Ge, X Y; Wang, J G; Wang, Y L; Wang, Y; Yu, Y; Li, P P; Lu, C B

    2015-08-20

    The hippocampal neuronal network oscillation at γ frequency band (γ oscillation) is generated by the precise interaction between interneurons and principle cells. γ oscillation is associated with attention, learning and memory and is impaired in the diseased conditions such as Alzheimer's disease (AD) and schizophrenia. Nicotinic acetylcholine receptor (nAChR) plays an important role in the regulation of hippocampal neurotransmission and network activity. It is not known whether nicotine modulates plasticity of network activity at γ oscillations in the hippocampus. In this study we investigated the effects of nicotine on the long-term changes of KA-induced γ oscillations. We found that hippocampal γ oscillations can be enhanced by a low concentration of nicotine (1μM), such an enhancement lasts for hours after washing out of nicotine, suggesting a form of synaptic plasticity, named as long-term oscillation at γ frequency band (LTOγ). Nicotine-induced LTOγ was mimicked by the selective α4β2 but not by α7 nAChR agonist and was involved in N-methyl-d-aspartate (NMDA) receptor activation as well as depended on excitatory and inhibitory neurotransmission. Our results indicate that nAChR activation induced plasticity in γ oscillation, which may be beneficial for the improvement of cognitive deficiency in AD and schizophrenia.

  5. Menthol Alone Upregulates Midbrain nAChRs, Alters nAChR Subtype Stoichiometry, Alters Dopamine Neuron Firing Frequency, and Prevents Nicotine Reward.

    PubMed

    Henderson, Brandon J; Wall, Teagan R; Henley, Beverley M; Kim, Charlene H; Nichols, Weston A; Moaddel, Ruin; Xiao, Cheng; Lester, Henry A

    2016-03-09

    Upregulation of β2 subunit-containing (β2*) nicotinic acetylcholine receptors (nAChRs) is implicated in several aspects of nicotine addiction, and menthol cigarette smokers tend to upregulate β2* nAChRs more than nonmenthol cigarette smokers. We investigated the effect of long-term menthol alone on midbrain neurons containing nAChRs. In midbrain dopaminergic (DA) neurons from mice containing fluorescent nAChR subunits, menthol alone increased the number of α4 and α6 nAChR subunits, but this upregulation did not occur in midbrain GABAergic neurons. Thus, chronic menthol produces a cell-type-selective upregulation of α4* nAChRs, complementing that of chronic nicotine alone, which upregulates α4 subunit-containing (α4*) nAChRs in GABAergic but not DA neurons. In mouse brain slices and cultured midbrain neurons, menthol reduced DA neuron firing frequency and altered DA neuron excitability following nAChR activation. Furthermore, menthol exposure before nicotine abolished nicotine reward-related behavior in mice. In neuroblastoma cells transfected with fluorescent nAChR subunits, exposure to 500 nm menthol alone also increased nAChR number and favored the formation of (α4)3(β2)2 nAChRs; this contrasts with the action of nicotine itself, which favors (α4)2(β2)3 nAChRs. Menthol alone also increases the number of α6β2 receptors that exclude the β3 subunit. Thus, menthol stabilizes lower-sensitivity α4* and α6 subunit-containing nAChRs, possibly by acting as a chemical chaperone. The abolition of nicotine reward-related behavior may be mediated through menthol's ability to stabilize lower-sensitivity nAChRs and alter DA neuron excitability. We conclude that menthol is more than a tobacco flavorant: administered alone chronically, it alters midbrain DA neurons of the nicotine reward-related pathway.

  6. Ligand Binding at the α4-α4 Agonist-Binding Site of the α4β2 nAChR Triggers Receptor Activation through a Pre-Activated Conformational State

    PubMed Central

    Indurthi, Dinesh C.; Lewis, Trevor M.; Ahring, Philip K.; Balle, Thomas; Chebib, Mary; Absalom, Nathan L.

    2016-01-01

    The α4β2 nicotinic acetylcholine receptor (nAChR) is the most abundant subtype in the brain and exists in two functional stoichiometries: (α4)3(β2)2 and (α4)2(β2)3. A distinct feature of the (α4)3(β2)2 receptor is the biphasic activation response to the endogenous agonist acetylcholine, where it is activated with high potency and low efficacy when two α4-β2 binding sites are occupied and with low potency/high efficacy when a third α4-α4 binding site is occupied. Further, exogenous ligands can bind to the third α4-α4 binding site and potentiate the activation of the receptor by ACh that is bound at the two α4-β2 sites. We propose that perturbations of the recently described pre-activation step when a third binding site is occupied are a key driver of these distinct activation properties. To investigate this, we used a combination of simple linear kinetic models and voltage clamp electrophysiology to determine whether transitions into the pre-activated state were increased when three binding sites were occupied. We separated the binding at the two different sites with ligands selective for the α4-β2 site (Sazetidine-A and TC-2559) and the α4-α4 site (NS9283) and identified that when a third binding site was occupied, changes in the concentration-response curves were best explained by an increase in transitions into a pre-activated state. We propose that perturbations of transitions into a pre-activated state are essential to explain the activation properties of the (α4)3(β2)2 receptor by acetylcholine and other ligands. Considering the widespread clinical use of benzodiazepines, this discovery of a conserved mechanism that benzodiazepines and ACh potentiate receptor activation via a third binding site can be exploited to develop therapeutics with similar properties at other cys-loop receptors. PMID:27552221

  7. The characterization of a novel rigid nicotine analog with alpha7-selective nAChR agonist activity and modulation of agonist properties by boron inclusion.

    PubMed

    Papke, Roger L; Zheng, Guangrong; Horenstein, Nicole A; Dwoskin, Linda P; Crooks, Peter A

    2005-09-01

    The alpha7 nAChR subtype is of particular interest as a potential therapeutic target since it has been implicated as a mediator of both cognitive and neuroprotective activity. The rigid nicotine analog ACME and the N-cyanoborane conjugate ACME-B are selective partial agonists of rat alpha7 receptors expressed in Xenopus oocytes, with no significant activation of either alpha3beta4 or alpha4beta2 receptors. ACME-B is both more potent and efficacious than ACME. The efficacies of ACME-B and ACME are approximately 26% and 10% of the efficacy of ACh, respectively. Similar N-conjugation of S(-)nicotine with cyanoborane decreased efficacy for alpha3beta4 and alpha4beta2 receptors, as well as for alpha7 nAChR. Structural comparison of ACME with the benzylidene anabaseines, another class of previously identified alpha7-selective agonists, suggests that they share a similar structural motif that may be applicable to other alpha7-selective agonists.

  8. Docking of 6-chloropyridazin-3-yl derivatives active on nicotinic acetylcholine receptors into molluscan acetylcholine binding protein (AChBP).

    PubMed

    Artali, Roberto; Bombieri, Gabriella; Meneghetti, Fiorella

    2005-04-01

    The crystal structure of Acetylcholine Binding Protein (AChBP), homolog of the ligand binding domain of nAChR, has been used as model for computational investigations on the ligand-receptor interactions of derivatives of 6-chloropyridazine substituted at C3 with 3,8-diazabicyclo[3.2.1]octane, 2,5-diazabicyclo[2.2.1]heptane and with piperazine and homopiperazine, substituted or not at N4. The ligand-receptor complexes have been analyzed by docking techniques using the binding site of HEPES complexed with AChBP as template. The good relationship between the observed binding affinity and the calculated docking energy confirms that this model provides a good starting point for understanding the binding domain of neuronal nicotinic receptors. An analysis of the possible factors significant for the ligand recognition has evidenced, besides the cation-pi interaction, the distance between the chlorine atom of the pyridazinyl group and the carbonylic oxygen of Leu B112 as an important parameter in the modulation of the binding energy.

  9. Reactivation of tabun-hAChE investigated by structurally analogous oximes and mutagenesis.

    PubMed

    Artursson, Elisabet; Akfur, Christine; Hörnberg, Andreas; Worek, Franz; Ekström, Fredrik

    2009-11-30

    The nerve agent tabun inhibits the essential enzyme acetylcholinesterase (AChE) by a rapid phosphoramidation of the catalytic serine residue. Oximes, such as K027 and HLö-7, can reactivate tabun-inhibited human AChE (tabun-hAChE) whereas the activity of their close structural analogue HI-6 is notably low. To investigate HI-6, K027 and HLö-7, residues lining the active-site gorge of hAChE were substituted and the effects on kinetic parameters for reactivation were determined. None of the mutants (Asp74Asn, Asp74Glu, Tyr124Phe, Tyr337Ala, Tyr337Phe, Phe338Val and Tyr341Ala) were able to facilitate HI-6-mediated reactivation of tabun-hAChE. In contrast, Tyr124Phe and Tyr337Phe induce a 2-2.5-fold enhancement of the bimolecular rate constant for K027 and HLö-7. The largest effects on the dissociation constant (3.5-fold increase) and rate constant (20-fold decrease) were observed for Tyr341Ala and Asp74Asn, respectively. These findings demonstrate the importance of residues located distant from the conjugate during the reactivation of tabun-hAChE.

  10. Identical kinetics of human erythrocyte and muscle acetylcholinesterase with respect to carbamate pre-treatment, residual activity upon soman challenge and spontaneous reactivation after withdrawal of the inhibitors.

    PubMed

    Herkert, Nadja M; Eckert, Saskia; Eyer, Peter; Bumm, Rudolf; Weber, Georg; Thiermann, Horst; Worek, Franz

    2008-04-18

    The efficacy of oxime treatment in soman poisoning is limited due to rapid aging of inhibited acetylcholinesterase (AChE). Pre-treatment with carbamates was shown to improve antidotal treatment substantially. Recently, by using a dynamically working in vitro model with real-time determination of membrane-bound AChE activity, we were able to demonstrate that pre-inhibition of human erythrocyte AChE with pyridostigmine or physostigmine resulted in a markedly higher residual AChE activity after inhibition by soman or paraoxon than in the absence of reversible inhibitors. The purpose of the present study was to compare the effect of carbamate pre-treatment and soman challenge with human erythrocyte and muscle homogenate AChE. Both enzyme sources were immobilized on particle filters which were perfused with acetylthiocholine, Ellman's reagent and phosphate buffer. AChE activity was continuously analyzed in a flow-through detector. Pre-inhibition of AChE with pyridostigmine or physostigmine resulted in a concentration-dependent increase in carbamylation, residual activity after soman inhibition and fraction of decarbamylation AChE after discontinuation of the inhibitors without differences between human erythrocyte and muscle AChE. This data support the view that human erythrocyte AChE is an adequate surrogate marker for synaptic AChE in OP poisoning.

  11. Centrally acting oximes in reactivation of tabun-phosphoramidated AChE.

    PubMed

    Kovarik, Zrinka; Maček, Nikolina; Sit, Rakesh K; Radić, Zoran; Fokin, Valery V; Barry Sharpless, K; Taylor, Palmer

    2013-03-25

    Organophosphates (OP) inhibit acetylcholinesterase (AChE, EC 3.1.1.7), both in peripheral tissues and central nervous system (CNS), causing adverse and sometimes fatal effects due to the accumulation of neurotransmitter acetylcholine (ACh). The currently used therapy, focusing on the reactivation of inhibited AChE, is limited to peripheral tissues because commonly used quaternary pyridinium oxime reactivators do not cross the blood brain barrier (BBB) at therapeutically relevant levels. A directed library of thirty uncharged oximes that contain tertiary amine or imidazole protonable functional groups that should cross the BBB as unionized species was tested as tabun-hAChE conjugate reactivators along with three reference oximes: DAM (diacetylmonoxime), MINA (monoisonitrosoacetone), and 2-PAM. The oxime RS150D [N-((1-(3-(2-((hydroxyimino)methyl)-1H-imidazol-1-yl)propyl)-1H-1,2,3-triazol-4-yl)methyl)benzamide] was highlighted as the most promising reactivator of the tabun-hAChE conjugate. We also observed that oximes RS194B [N-(2-(azepan-1-yl)ethyl)-2-(hydroxyimino)acetamide] and RS41A [2-(hydroxyimino)-N-(2-(pyrrolidin-1-yl)ethyl)acetamide], which emerged as lead uncharged reactivators of phosphylated hAChE with other OPs (sarin, cyclosarin and VX), exhibited only moderate reactivation potency for tabun inhibited hAChE. This implies that geometry of oxime access to the phosphorus atom conjugated to the active serine is an important criterion for efficient reactivation, along with the chemical nature of the conjugated moiety: phosphorate, phosphonate, or phosphoramidate. Moreover, modification of the active center through mutagenesis enhances the rates of reactivation. The phosphoramidated-hAChE choline-binding site mutant Y337A showed three-times enhanced reactivation capacity with non-triazole imidazole containing aldoximes (RS113B, RS113A and RS115A) and acetamide derivative (RS194B) than with 2PAM.

  12. Is fast fiber innervation responsible for increased acetylcholinesterase activity in reinnervating soleus muscles?

    NASA Technical Reports Server (NTRS)

    Misulis, K. E.; Dettbarn, W. D.

    1985-01-01

    An investigation was conducted as to whether the predominantly slow SOL, which is low in AChE activity, is initially reinnervated by axons that originally innervated fast muscle fibers with high AChE activity, such as those of the EDL. Local denervation of the SOL in the guinea pig was performed because this muscle is composed solely of slow (type I) fibers; thereby virtually eliminating the possibility of homologous muscle fast fiber innervation. The overshoot in this preparation was qualitatively similar to that seen with distal denervation in the guinea pig and local and distal denervation in the rat. Thus, initial fast fiber innvervation is not responsible for the patterns of change in AChE activity seen with reinnervation in the SOL. It is concluded that the neural control of AChe is different in these two muscles and may reflect specific differences in the characteristics of AChE regulation in fast and slow muscle.

  13. Menthol Alone Upregulates Midbrain nAChRs, Alters nAChR Subtype Stoichiometry, Alters Dopamine Neuron Firing Frequency, and Prevents Nicotine Reward

    PubMed Central

    Henderson, Brandon J.; Wall, Teagan R.; Henley, Beverley M.; Kim, Charlene H.; Nichols, Weston A.; Moaddel, Ruin; Xiao, Cheng

    2016-01-01

    Upregulation of β2 subunit-containing (β2*) nicotinic acetylcholine receptors (nAChRs) is implicated in several aspects of nicotine addiction, and menthol cigarette smokers tend to upregulate β2* nAChRs more than nonmenthol cigarette smokers. We investigated the effect of long-term menthol alone on midbrain neurons containing nAChRs. In midbrain dopaminergic (DA) neurons from mice containing fluorescent nAChR subunits, menthol alone increased the number of α4 and α6 nAChR subunits, but this upregulation did not occur in midbrain GABAergic neurons. Thus, chronic menthol produces a cell-type-selective upregulation of α4* nAChRs, complementing that of chronic nicotine alone, which upregulates α4 subunit-containing (α4*) nAChRs in GABAergic but not DA neurons. In mouse brain slices and cultured midbrain neurons, menthol reduced DA neuron firing frequency and altered DA neuron excitability following nAChR activation. Furthermore, menthol exposure before nicotine abolished nicotine reward-related behavior in mice. In neuroblastoma cells transfected with fluorescent nAChR subunits, exposure to 500 nm menthol alone also increased nAChR number and favored the formation of (α4)3(β2)2 nAChRs; this contrasts with the action of nicotine itself, which favors (α4)2(β2)3 nAChRs. Menthol alone also increases the number of α6β2 receptors that exclude the β3 subunit. Thus, menthol stabilizes lower-sensitivity α4* and α6 subunit-containing nAChRs, possibly by acting as a chemical chaperone. The abolition of nicotine reward-related behavior may be mediated through menthol's ability to stabilize lower-sensitivity nAChRs and alter DA neuron excitability. We conclude that menthol is more than a tobacco flavorant: administered alone chronically, it alters midbrain DA neurons of the nicotine reward-related pathway. SIGNIFICANCE STATEMENT Menthol, the most popular flavorant for tobacco products, has been considered simply a benign flavor additive. However, as we show here

  14. miR-434-3p and DNA hypomethylation co-regulate eIF5A1 to increase AChRs and to improve plasticity in SCT rat skeletal muscle

    PubMed Central

    Shang, Fei-Fei; Xia, Qing-Jie; Liu, Wei; Xia, Lei; Qian, Bao-Jiang; You, Ling; He, Mu; Yang, Jin-Liang; Wang, Ting-Hua

    2016-01-01

    Acetylcholine receptors (AChRs) serve as connections between motor neurons and skeletal muscle and are essential for recovery from spinal cord transection (SCT). Recently, microRNAs have emerged as important potential biotherapeutics for several diseases; however, whether miRNAs operate in the modulation of AChRs remains unknown. We found increased AChRs numbers and function scores in rats with SCT; these increases were reduced following the injection of a eukaryotic translation initiation factor 5A1 (eIF5A1) shRNA lentivirus into the hindlimb muscle. Then, high-throughput screening for microRNAs targeting eIF5A1 was performed, and miR-434-3p was found to be robustly depleted in SCT rat skeletal muscle. Furthermore, a highly conserved miR-434-3p binding site was identified within the mRNA encoding eIF5A1 through bioinformatics analysis and dual-luciferase assay. Overexpression or knockdown of miR-434-3p in vivo demonstrated it was a negative post-transcriptional regulator of eIF5A1 expression and influenced AChRs expression. The microarray-enriched Gene Ontology (GO) terms regulated by miR-434-3p were muscle development terms. Using a lentivirus, one functional gene (map2k6) was confirmed to have a similar function to that of miR-434-3p in GO terms. Finally, HRM and MeDIP-PCR analyses revealed that DNA demethylation also up-regulated eIF5A1 after SCT. Consequently, miR-434-3p/eIF5A1 in muscle is a promising potential biotherapy for SCI repair. PMID:26964899

  15. [Cation ions modulate the ACh-sensitive current in type II vestibular hair cells of guinea pigs].

    PubMed

    Guo, Chang-Kai; Zhang, Song; Kong, Wei-Jia; Li, Qing-Tian; Li, Zhi-Wang

    2006-04-25

    (+). In the Ca(2+)-free external solution, ACh only activated a very small current; however, the ACh-sensitive current demonstrated a Ca(2+)-dependent inhibition effect in high concentration of Ca(2+)solution. In addition, the ACh-sensitive current was inhibited by increasing of the concentration of intracellular Mg(2+). In conclusion, the present results demonstrate that ACh plays an important role in the vestibular efferent system. The fact that Na(+) is not involved in the ACh-sensitive current will not favor the well-known profile of alpha9-nAChR, which is reported to display a small but important permeability to Na(+). It is also suggested that, in vivo, the amplitude of the ACh-induced hyperpolarization may strongly depend on the concentration of extracellular Ca(2+)and intracellular Mg(2+).

  16. Acetylcholinesterase (AChE) gene modification in transgenic animals: functional consequences of selected exon and regulatory region deletion.

    PubMed

    Camp, Shelley; Zhang, Limin; Marquez, Michael; de la Torre, Brian; Long, Jeffery M; Bucht, Goran; Taylor, Palmer

    2005-12-15

    . delaTorre, P. Taylor, Knockout mice with deletions of alternatively spliced exons of Acetylcholinesterase, in: N.C. Inestrosa, E.O. Campus (Eds.), VII International Meeting on Cholinesterases, Pucon-Chile Cholinesterases in the Second Millennium: Biomolecular and Pathological Aspects. P. Universidad Catholica de Chile-FONDAP Biomedicina, 2004, pp. 43-48; R.Y.Y. Chan, C. Boudreau-Larivière, L.A. Angus, F. Mankal, B.J. Jasmin, An intronic enhancer containing an N-box motif is required for synapse- and tissue-specific expression of the acetylcholinesterase gene in skeletal muscle fibers. Proc. Natl. Acad. Sci. USA 96 (1999) 4627-4632], is also presented. The intronic region was floxed and then deleted by mating with Ella-cre transgenic mice. The deletion of this region produced a dramatic phenotype; a mouse with near normal AChE expression in brain and other CNS tissues, but no AChE expression in muscle. Phenotype and AChE tissue activities are compared with the total AChE knockout mouse [W. Xie, J.A. Chatonnet, P.J. Wilder, A. Rizzino, R.D. McComb, P. Taylor, S.H. Hinrichs, O. Lockridge, Postnatal developmental delay and supersensitivity to organophosphate in gene-targeted mice lacking acetylcholinesterase. J. Pharmacol. Exp. Ther. 293 (3) (2000) 896-902].

  17. Activation of muscarinic receptors in porcine airway smooth muscle elicits a transient increase in phospholipase D activity.

    PubMed

    Mamoon, A M; Smith, J; Baker, R C; Farley, J M

    1999-01-01

    Phospholipase D (PLD) is a phosphodiesterase that catalyses hydrolysis of phosphatidylcholine to produce phosphatidic acid and choline. In the presence of ethanol, PLD also catalyses the formation of phosphatidylethanol, which is a unique characteristic of this enzyme. Muscarinic receptor-induced changes in the activity of PLD were investigated in porcine tracheal smooth muscle by measuring the formation of [3H]phosphatidic acid ([3H]PA) and [3H]phosphatidylethanol ([3H]PEth) after labeling the muscle strips with [3H]palmitic acid. The cholinergic receptor agonist acetylcholine (Ach) significantly but transiently increased formation of both [3H]PA and [3H]PEth in a concentration-dependent manner (>105-400% vs. controls in the presence of 10(-6) to 10(-4) M Ach) when pretreated with 100 mM ethanol. The Ach receptor-mediated increase in PLD activity was inhibited by atropine (10(-6) M), indicating that activation of PLD occurred via muscarinic receptors. Activation of protein kinase C (PKC) by phorbol-12-myristate-13-acetate (PMA) increased PLD activity that was effectively blocked by the PKC inhibitors calphostin C (10(-8) to 10(-6) M) and GFX (10(-8) to 10(-6) M). Ach-induced increases in PLD activity were also significantly, but incompletely, inhibited by both GFX and calphostin C. From the present data, we conclude that in tracheal smooth muscle, muscarinic acetylcholine receptor-induced PLD activation is transient in nature and coupled to these receptors via PKC. However, PKC activation is not solely responsible for Ach-induced activation of PLD in porcine tracheal smooth muscle.

  18. Comparative study on short- and long-term behavioral consequences of organophosphate exposure: relationship to AChE mRNA expression.

    PubMed

    López-Granero, Caridad; Cardona, Diana; Giménez, Estela; Lozano, Rafael; Barril, José; Aschner, Michael; Sánchez-Santed, Fernando; Cañadas, Fernando

    2014-01-01

    Organophosphates (OPs) affect behavior by inhibiting acetylcholinesterase (AChE). While the cognitive short-term effects may be directly attributed to this inhibition, the mechanisms that underlie OP's long-term cognitive effects remain controversial and poorly understood. Accordingly, two experiments were designed to assess the effects of OPs on cognition, and to ascertain whether both the short- and long-term effects of are AChE-dependent. A single subcutaneous dose of 250 mg/kg chlorpyrifos (CPF), 1.5mg/kg diisopropylphosphorofluoridate (DFP) or 15 mg/kg parathion (PTN) was administered to male Wistar rats. Spatial learning was evaluated 72 h or 23 weeks after exposure, and impulsive choice was tested at 10 and 30 weeks following OPs administration (experiment 1 and 2, respectively). Brain soluble and membrane-bound AChE activity, synaptic AChE-S mRNA, read-through AChE-R mRNA and brain acylpeptide hydrolase (APH) activity (as alternative non-cholinergic target) were analyzed upon completion of the behavioral testing (17 and 37 weeks after OPs exposure). Both short- and long-term CPF treatment caused statistically significant effects on spatial learning, while PTN treatment led only to statistically significant short-term effects. Neither CPF, DFP nor PTN affected the long-term impulsivity response. Long-term exposure to CPF and DFP significantly decreased AChE-S and AChE-R mRNA, while in the PTN treated group only AChE-S mRNA levels were decreased. However, after long-term OP exposure, soluble and membrane-bound AChE activity was indistinguishable from controls. Finally, no changes were noted in brain APH activity in response to OP treatment. Taken together, this study demonstrates long-term effects of OPs on AChE-S and AChE-R mRNA in the absence of changes in AChE soluble and membrane-bound activity. Thus, changes in AChE mRNA expression imply non-catalytic properties of the AChE enzyme.

  19. Simvastatin prevents β-amyloid(25-35)-impaired neurogenesis in hippocampal dentate gyrus through α7nAChR-dependent cascading PI3K-Akt and increasing BDNF via reduction of farnesyl pyrophosphate.

    PubMed

    Wang, Conghui; Chen, Tingting; Li, Guoxi; Zhou, Libin; Sha, Sha; Chen, Ling

    2015-10-01

    Simvastatin (SV) is reported to improve cognition and slow progression of Alzheimer's disease (AD), however underlying mechanism still remains unclear. In hippocampal dentate gyrus (DG), β-amyloid (Aβ) selectively impairs survival and neurite growth of newborn neurons in the 2(nd) week after birth. The aim of this study was to examine the effects of SV on the impairment of neurogenesis and the spatial cognitive deficits in Aβ25-35 (3 nmol)-injected (i.c.v.) mice (Aβ25-35-mice). Herein, we reported that the SV-treatment (20 mg/kg) on days 2-14 after BrdU-injection could dose-dependently protect the survival and neurite growth of newborn neurons, which was blocked by the α7nAChR antagonist MLA or the farnesol (FOH) that can convert to farnesyl pyrophosphate (FPP), but not the α4β2nAChR antagonist DHβE. The SV-treatment in Aβ25-35-mice rescued the decline of Akt phosphorylation and increased the ERK1/2 phosphorylation in hippocampus, which was sensitive to MLA and FOH. The PI3K inhibitor LY294002 could abolish the SV-protected neurogenesis in Aβ25-35-mice, but the MEK inhibitor U0126 had no effects. The SV-treatment could correct the decline of hippocampal BDNF concentration in Aβ25-35-mice, which was blocked by MLA and FOH. Using Morris water maze and Y-maze tasks, we further observed that the SV-treatment in Aβ25-35-mice could improve their spatial cognitive deficits, which was sensitive to the application of FOH. The results indicate that the SV-treatment in Aβ25-35-mice via reduction of FPP can protect neurogenesis through α7nAChR-cascading PI3K-Akt and increasing BDNF, which may improve spatial cognitive function.

  20. Assessing and Increasing Physical Activity

    ERIC Educational Resources Information Center

    Van Camp, Carole M.; Hayes, Lynda B.

    2012-01-01

    Increasing physical activity is a crucial component of any comprehensive approach to combat the growing obesity epidemic. This review summarizes recent behavioral research on the measurement of physical activity and interventions aimed at increasing physical activity and provides directions for future research.

  1. In Vitro Activity of ACH-702, a New Isothiazoloquinolone, against Nocardia brasiliensis Compared with Econazole and the Carbapenems Imipenem and Meropenem Alone or in Combination with Clavulanic Acid ▿

    PubMed Central

    Vera-Cabrera, Lucio; Campos-Rivera, Mayra Paola; Escalante-Fuentes, Wendy G.; Pucci, Michael J.; Ocampo-Candiani, Jorge; Welsh, Oliverio

    2010-01-01

    The in vitro activities of ACH-702 and other antimicrobials against 30 Nocardia brasiliensis isolates were tested. The MIC50 (MIC for 50% of the strains tested) and MIC90 values of ACH-702 were 0.125 and 0.5 μg/ml. The same values for econazole were 2 and 4 μg/ml. The MIC50 and MIC90 values of imipenem and meropenem were 64 and >64 μg/ml and 2 and 8 μg/ml, respectively; the addition of clavulanic acid to the carbapenems had no effect. PMID:20308390

  2. Acetylcholinesterase Regulates Skeletal In Ovo Development of Chicken Limbs by ACh-Dependent and -Independent Mechanisms

    PubMed Central

    Spieker, Janine; Ackermann, Anica; Salfelder, Anika; Vogel-Höpker, Astrid; Layer, Paul G.

    2016-01-01

    Formation of the vertebrate limb presents an excellent model to analyze a non-neuronal cholinergic system (NNCS). Here, we first analyzed the expression of acetylcholinesterase (AChE) by IHC and of choline acetyltransferase (ChAT) by ISH in developing embryonic chicken limbs (stages HH17-37). AChE outlined formation of bones, being strongest at their distal tips, and later also marked areas of cell death. At onset, AChE and ChAT were elevated in two organizing centers of the limb anlage, the apical ectodermal ridge (AER) and zone of polarizing activity (ZPA), respectively. Thereby ChAT was expressed shortly after AChE, thus strongly supporting a leading role of AChE in limb formation. Then, we conducted loss-of-function studies via unilateral implantation of beads into chicken limb anlagen, which were soaked in cholinergic components. After varying periods, the formation of cartilage matrix and of mineralizing bones was followed by Alcian blue (AB) and Alizarin red (AR) stainings, respectively. Both acetylcholine (ACh)- and ChAT-soaked beads accelerated bone formation in ovo. Notably, inhibition of AChE by BW284c51, or by the monoclonal antibody MAB304 delayed cartilage formation. Since bead inhibition of BChE was mostly ineffective, an ACh-independent action during BW284c51 and MAB304 inhibition was indicated, which possibly could be due to an enzymatic side activity of AChE. In conclusion, skeletogenesis in chick is regulated by an ACh-dependent cholinergic system, but to some extent also by an ACh-independent aspect of the AChE protein. PMID:27574787

  3. Toxicological and Biochemical Characterizations of AChE in Phosalone-Susceptible and Resistant Populations of the Common Pistachio Psyllid, Agonoscena pistaciae

    PubMed Central

    Alizadeh, Ali; Talebi-Jahromi, Khalil; Hosseininaveh, Vahid; Ghadamyari, Mohammad

    2014-01-01

    The toxicological and biochemical characteristics of acetylcholinesterases (AChE) in nine populations of the common pistachio psyllid, Agonoscena pistaciae Burckhardt and Lauterer (Hemiptera: Psyllidae), were investigated in Kerman Province, Iran. Nine A. pistaciae populations were collected from pistachio orchards, Pistacia vera L. (Sapindales: Anacardiaceae), located in Rafsanjan, Anar, Bam, Kerman, Shahrbabak, Herat, Sirjan, Pariz, and Paghaleh regions of Kerman province. The previous bioassay results showed these populations were susceptible or resistant to phosalone, and the Rafsanjan population was most resistant, with a resistance ratio of 11.3. The specific activity of AChE in the Rafsanjan population was significantly higher than in the susceptible population (Bam). The affinity (KM) and hydrolyzing efficiency (Vmax) of AChE on acetylthiocholine iodide, butyrylthiocholine iodide, and propionylthiocholine odide as artificial substrates were clearly lower in the Bam population than that in the Rafsanjan population. These results indicated that the AChE of the Rafsanjan population had lower affinity to these substrates than that of the susceptible population. The higher Vmax value in the Rafsanjan population compared to the susceptible population suggests a possible over expression of AChE in the Rafsanjan population. The in vitro inhibitory effect of several organophosphates and carbamates on AChE of the Rafsanjan and Bam populations was determined. Based on I50, the results showed that the ratios of AChE insensitivity of the resistant to susceptible populations were 23 and 21.7-fold to monocrotophos and phosphamidon, respectively. Whereas, the insensitivity ratios for Rafsanjan population were 0.86, 0.8, 0.78, 0.46, and 0.43 for carbaryl, eserine, propoxur, m-tolyl methyl carbamate, and carbofuran, respectively, suggesting negatively correlated sensitivity to organophosphate-insensitive AChE. Therefore, AChE from the Rafsanjan population showed negatively

  4. Novel AChE Inhibitors for Sustainable Insecticide Resistance Management

    PubMed Central

    Alout, Haoues; Labbé, Pierrick; Berthomieu, Arnaud; Djogbénou, Luc; Leonetti, Jean-Paul; Fort, Philippe; Weill, Mylène

    2012-01-01

    Resistance to insecticides has become a critical issue in pest management and it is particularly chronic in the control of human disease vectors. The gravity of this situation is being exacerbated since there has not been a new insecticide class produced for over twenty years. Reasoned strategies have been developed to limit resistance spread but have proven difficult to implement in the field. Here we propose a new conceptual strategy based on inhibitors that preferentially target mosquitoes already resistant to a currently used insecticide. Application of such inhibitors in rotation with the insecticide against which resistance has been selected initially is expected to restore vector control efficacy and reduce the odds of neo-resistance. We validated this strategy by screening for inhibitors of the G119S mutated acetylcholinesterase-1 (AChE1), which mediates insensitivity to the widely used organophosphates (OP) and carbamates (CX) insecticides. PyrimidineTrione Furan-substituted (PTF) compounds came out as best hits, acting biochemically as reversible and competitive inhibitors of mosquito AChE1 and preferentially inhibiting the mutated form, insensitive to OP and CX. PTF application in bioassays preferentially killed OP-resistant Culex pipiens and Anopheles gambiae larvae as a consequence of AChE1 inhibition. Modeling the evolution of frequencies of wild type and OP-insensitive AChE1 alleles in PTF-treated populations using the selectivity parameters estimated from bioassays predicts a rapid rise in the wild type allele frequency. This study identifies the first compound class that preferentially targets OP-resistant mosquitoes, thus restoring OP-susceptibility, which validates a new prospect of sustainable insecticide resistance management. PMID:23056599

  5. Calcium signalling mediated through α7 and non-α7 nAChR stimulation is differentially regulated in bovine chromaffin cells to induce catecholamine release

    PubMed Central

    del Barrio, Laura; Egea, Javier; León, Rafael; Romero, Alejandro; Ruiz, Ana; Montero, Mayte; Álvarez, Javier; López, Manuela G

    2011-01-01

    BACKGROUND AND PURPOSE Ca2+ signalling and exocytosis mediated by nicotinic receptor (nAChR) subtypes, especially the α7 nAChR, in bovine chromaffin cells are still matters of debate. EXPERIMENTAL APPROACH We have used chromaffin cell cultures loaded with Fluo-4 or transfected with aequorins directed to the cytosol or mitochondria, several nAChR agonists (nicotine, 5-iodo-A-85380, PNU282987 and choline), and the α7 nAChR allosteric modulator PNU120596. KEY RESULTS Minimal [Ca2+]c transients, induced by low concentrations of selective α7 nAChR agonists and nicotine, were markedly increased by the α7 nAChR allosteric modulator PNU120596. These potentiated responses were completely blocked by the α7 nAChR antagonist α-bungarotoxin (α7-modulated-response). Conversely, high concentrations of the α7 nAChR agonists, nicotine or 5-iodo-A-85380 induced larger [Ca2+]c transients, that were blocked by mecamylamine but were unaffected by α-bungarotoxin (non-α7 response). [Ca2+]c increases mediated by α7 nAChR were related to Ca2+ entry through non-L-type Ca2+ channels, whereas non-α7 nAChR-mediated signals were related to L-type Ca2+ channels; Ca2+-induced Ca2+-release contributed to both responses. Mitochondrial involvement in the control of [Ca2+]c transients, mediated by either receptor, was minimal. Catecholamine release coupled to α7 nAChRs was more efficient in terms of catecholamine released/[Ca2+]c. CONCLUSIONS AND IMPLICATIONS [Ca2+]c and catecholamine release mediated by α7 nAChRs required an allosteric modulator and low doses of the agonist. At higher agonist concentrations, the α7 nAChR response was lost and the non-α7 nAChRs were activated. Catecholamine release might therefore be regulated by different nAChR subtypes, depending on agonist concentrations and the presence of allosteric modulators of α7 nAChRs. PMID:20840468

  6. Altruistic cooperation during foraging by the Ache, and the evolved human predisposition to cooperate.

    PubMed

    Hill, Kim

    2002-03-01

    This paper presents quantitative data on altruistic cooperation during food acquisition by Ache foragers. Cooperative activities are defined as those that entail a cost of time and energy to the donor but primarily lead to an increase in the foraging success of the recipient. Data show that Ache men and women spend about 10% of all foraging time engaged in altruistic cooperation on average, and that on some days they may spend more than 50% of their foraging time in such activities. The most time-consuming cooperative activity for both sexes is helping during the pursuit of game animals, a pattern that is probably linked to the widespread sharing of game by Ache foragers. Cooperative food acquisition and subsequent food redistribution in hunter-gatherer societies are critical behaviors that probably helped shape universal, evolved, cooperative tendencies that are well illustrated in modern experimental economics.

  7. Increased Spreading Activation in Depression

    ERIC Educational Resources Information Center

    Foster, Paul S.; Yung, Raegan C.; Branch, Kaylei K.; Stringer, Kristi; Ferguson, Brad J.; Sullivan, William; Drago, Valeria

    2011-01-01

    The dopaminergic system is implicated in depressive disorders and research has also shown that dopamine constricts lexical/semantic networks by reducing spreading activation. Hence, depression, which is linked to reductions of dopamine, may be associated with increased spreading activation. However, research has generally found no effects of…

  8. Acetylcholinesterase (AChE)--amyloid-beta-peptide complexes in Alzheimer's disease. the Wnt signaling pathway.

    PubMed

    Inestrosa, Nibaldo C; Urra, Soledad; Colombres, Marcela

    2004-11-01

    Alzheimer's disease (AD) is characterized by selective neuronal cell death, which is probably caused by amyloid beta-peptide (Abeta) oligomers and fibrils. We have found that acetylcholinesterase (AChE), a senile plaque component, increases amyloid fibril assembly with the formation of highly toxic complexes (Abeta-AChE). The neurotoxic effect induced by Abeta-AChE complexes was higher than that induced by the Abeta peptide alone as shown both in vitro (hippocampal neurons) and in vivo (rats injected with Abeta peptide in the dorsal hippocampus). Interestingly, treatment with Abeta-AChE complexes decreases the cytoplasmic beta-catenin level, a key component of Wnt signaling. Conversely, the activation of this signaling pathway by Wnt-3a promotes neuronal survival and rescues changes in Wnt components (activation or subcellular localization). Moreover Frzb-1, a Wnt antagonist reverses the Wnt-3a neuroprotection effect against Abeta neurotoxicity. Compounds that mimic the Wnt signaling or modulate the cross-talking with this pathway could be used as neuroprotective agents for therapeutic strategies in AD patients.

  9. Chlorpyrifos and Chlorpyrifos-Oxon Inhibit Axonal Growth by Interfering with the Morphogenic Activity of Acetylcholinesterase

    PubMed Central

    Yang, Dongren; Howard, Angela; Bruun, Donald; Ajua-Alemanj, Mispa; Pickart, Cecile; Lein, Pamela J.

    2008-01-01

    A primary role of acetylcholinesterase (AChE) is regulation of cholinergic neurotransmission by hydrolysis of synaptic acetylcholine. In the developing nervous system, however, AChE also functions as a morphogenic factor to promote axonal growth. This raises the question of whether organophosphorus pesticides (OPs) that are known to selectively bind to and inactivate the enzymatic function of AChE also interfere with its morphogenic function to perturb axonogenesis. To test this hypothesis, we exposed primary cultures of sensory neurons derived from embryonic rat dorsal root ganglia (DRG) to chlorpyrifos (CPF) or its oxon metabolite (CPFO). Both OPs significantly decreased axonal length at concentrations that had no effect on cell viability, protein synthesis or the enzymatic activity of AChE. Comparative analyses of the effects of CPF and CPFO on axonal growth in DRG neurons cultured from AChE nullizygous (AChE−/−) versus wildtype (AChE+/+) mice indicated that while these OPs inhibited axonal growth in AChE+/+ DRG neurons, they had no effect on axonal growth in AChE−/− DRG neurons. However, transfection of AChE−/− DRG neurons with cDNA encoding full-length AChE restored the wildtype response to the axon inhibitory effects of OPs. These data indicate that inhibition of axonal growth by OPs requires AChE, but the mechanism involves inhibition of the morphogenic rather than enzymatic activity of AChE. These findings suggest a novel mechanism for explaining not only the functional deficits observed in children and animals following developmental exposure to OPs, but also the increased vulnerability of the developing nervous system to OPs. PMID:18076960

  10. Assessing the reactivation efficacy of hydroxylamine anion towards VX-inhibited AChE: a computational study.

    PubMed

    Khan, Md Abdul Shafeeuulla; Ganguly, Bishwajit

    2012-05-01

    Oximate anions are used as potential reactivating agents for OP-inhibited AChE because of they possess enhanced nucleophilic reactivity due to the α-effect. We have demonstrated the process of reactivating the VX-AChE adduct with formoximate and hydroxylamine anions by applying the DFT approach at the B3LYP/6-311 G(d,p) level of theory. The calculated results suggest that the hydroxylamine anion is more efficient than the formoximate anion at reactivating VX-inhibited AChE. The reaction of formoximate anion and the VX-AChE adduct is a three-step process, while the reaction of hydroxylamine anion with the VX-AChE adduct seems to be a two-step process. The rate-determining step in the process is the initial attack on the VX of the VX-AChE adduct by the nucleophile. The subsequent steps are exergonic in nature. The potential energy surface (PES) for the reaction of the VX-AChE adduct with hydroxylamine anion reveals that the reactivation process is facilitated by the lower free energy of activation (by a factor of 1.7 kcal mol(-1)) than that of the formoximate anion at the B3LYP/6-311 G(d,p) level of theory. The higher free energy of activation for the reverse reactivation reaction between hydroxylamine anion and the VX-serine adduct further suggests that the hydroxylamine anion is a very good antidote agent for the reactivation process. The activation barriers calculated in solvent using the polarizable continuum model (PCM) for the reactivation of the VX-AChE adduct with hydroxylamine anion were also found to be low. The calculated results suggest that V-series compounds can be more toxic than G-series compounds, which is in accord with earlier experimental observations.

  11. [Cl-]i modulation of Ca2+-regulated exocytosis in ACh-stimulated antral mucous cells of guinea pig.

    PubMed

    Shimamoto, Chikao; Umegaki, Eiji; Katsu, Ken-ichi; Kato, Masumi; Fujiwara, Shoko; Kubota, Takahiro; Nakahari, Takashi

    2007-10-01

    The effects of intracellular Cl- concentration ([Cl-]i) on acetylcholine (ACh)-stimulated exocytosis were studied in guinea pig antral mucous cells by video microscopy. ACh activated Ca2+-regulated exocytosis (an initial phase followed by a sustained phase). Bumetanide (20 microM) or a Cl- -free (NO3-) solution enhanced it; in contrast, 5-nitro-2-(3-phenylpropylamino)benzoic acid (NPPB, a Cl- channel blocker) decreased it and eliminated the enhancement induced by bumetanide or NO3- solution. ACh and Ca2+ dose-response studies demonstrated that NO3- solution does not shift their dose-response curves, and ATP depletion studies by dinitrophenol or anoxia demonstrated that exposure of NO3- solution prior to ATP depletion induced an enhanced initial phase followed by a sustained phase, whereas exposure of NO3- solution after ATP depletion induced only a sustained phase. Intracellular Ca2+ concentration ([Ca2+]i) measurements showed that bumetanide and NO3- solution enhanced the ACh-stimulated [Ca2+]i increase. Measurements of [Cl-]i revealed that ACh decreases [Cl-]i and that bumetanide and NO3- solution decreased [Cl-]i and enhanced the ACh-evoked [Cl-]i decrease; in contrast, NPPB increased [Cl-]i and inhibited the [Cl-]i decrease induced by ACh, bumetanide, or NO3- solution. These suggest that [Cl-]i modulates [Ca2+]i increase and ATP-dependent priming. In conclusion, a decrease in [Cl-]i accelerates ATP-dependent priming and [Ca2+]i increase, which enhance Ca2+-regulated exocytosis in ACh-stimulated antral mucous cells.

  12. The dual-acting H3 receptor antagonist and AChE inhibitor UW-MD-71 dose-dependently enhances memory retrieval and reverses dizocilpine-induced memory impairment in rats.

    PubMed

    Khan, Nadia; Saad, Ali; Nurulain, Syed M; Darras, Fouad H; Decker, Michael; Sadek, Bassem

    2016-01-15

    Both the histamine H3 receptor (H3R) and acetylcholine esterase (AChE) are involved in the regulation of release and metabolism of acetylcholine and several other central neurotransmitters. Therefore, dual-active H3R antagonists and AChE inhibitors (AChEIs) have shown in several studies to hold promise to treat cognitive disorders like Alzheimer's disease (AD). The novel dual-acting H3R antagonist and AChEI 7-(3-(piperidin-1-yl)propoxy)-1,2,3,9-tetrahydropyrrolo[2,1-b]quinazoline (UW-MD-71) with excellent selectivity profiles over both the three other HRs as well as the AChE's isoenzyme butyrylcholinesterase (BChE) shows high and balanced in vitro affinities at both H3R and AChE with IC50 of 33.9nM and hH3R antagonism with Ki of 76.2nM, respectively. In the present study, the effects of UW-MD-71 (1.25-5mg/kg, i.p.) on acquisition, consolidation, and retrieval in a one-trial inhibitory avoidance task in male rats were investigated applying donepezil (DOZ) and pitolisant (PIT) as reference drugs. Furthermore, the effects of UW-MD-71 on memory deficits induced by the non-competitive N-methyl-d-aspartate (NMDA) antagonist dizocilpine (DIZ) were tested. Our results indicate that administration of UW-MD-71 before the test session dose-dependently increased performance and enhanced procognitive effect on retrieval. However neither pre- nor post-training acute systemic administration of UW-MD-71 facilitated acquisition or consolidation. More importantly, UW-MD-71 (2.5mg/kg, i.p.) ameliorated the DIZ-induced amnesic effects. Furthermore, the procognitive activity of UW-MD-71 in retrieval was completely reversed and partly abrogated in DIZ-induced amnesia when rats were pretreated with the centrally-acting H2R antagonist zolantidine (ZOL), but not with the CNS penetrant H1R antagonist pyrilamine (PYR). These results demonstrate the procognitive effects of UW-MD-71 in two in vivo memory models, and are to our knowledge the first demonstration in vivo that a potent dual

  13. Effect of acetylcholinesterase (AChE) point-of-care testing in OP poisoning on knowledge, attitudes and practices of treating physicians in Sri Lanka

    PubMed Central

    2014-01-01

    Background Toxicology and Emergency medicine textbooks recommend measurement of acetylcholinesterase (AChE) in all symptomatic cases of organophosphorus (OP) poisoning but laboratory facilities are limited in rural Asia. The accuracy of point-of-care (POC) acetylcholinesterase testing has been demonstrated but it remains to be shown whether results would be valued by clinicians. This study aims to assess the effect of seeing AChE POC test results on the knowledge, attitudes and practices of doctors who frequently manage OP poisoning. Methods We surveyed 23 clinicians, who had different levels of exposure to seeing AChE levels in OP poisoned patients, on a) knowledge of OP poisoning and biomarker interpretation, b) attitudes towards AChE in guiding poison management, oxime therapy and discharge decisions, and c) practices of ordering AChE in poisoning scenarios. Results An overall high proportion of doctors valued the test (68-89%). However, we paradoxically found that doctors who were more experienced in seeing AChE results valued the test less. Lower proportions valued the test in guidance of acute poisoning management (50%, p = 0.015) and guidance of oxime therapy (25%, p = 0.008), and it was apparent it would not generally be used to facilitate early discharge. The highest proportion of respondents valued it on admission (p < 0.001). A lack of correlation of test results with the clinical picture, and a perception that the test was a waste of money when compared to clinical observation alone were also comments raised by some of the respondents. Greater experience with seeing AChE test results was associated with increased knowledge (p = 0.034). However, a disproportionate lack of knowledge on interpretation of biomarkers and the pharmacology of oxime therapy (12-50%) was noted, when compared with knowledge on the mechanism of OP poisoning and management (78-90%). Conclusions Our findings suggest an AChE POC test may not be valued by rural doctors. The practical

  14. Generation of Recombinant Human AChE Op-Scavengers With Extended Circulatory Longevity

    DTIC Science & Technology

    2005-04-01

    AChE PEGylation results in a major reduction of the immunogenicity of the enzyme. In structure -function studies of AChE, we compared the reactivities...BChE). Extensive structural and biochemical analyses of over twenty forms of recombinant AChEs allowed us to determine an hierarchical pattern by...glycan structures that do not conform with the classical complex-type of oligosaccharides typical of animal cell proteins or which were entirely devoid of

  15. Increase in composite binder activity

    NASA Astrophysics Data System (ADS)

    Fediuk, R.; Smoliakov, A.; Stoyushko, N.

    2016-11-01

    The binder of portland cement (51-59 wt.%), fly ash of thermal power stations (3644 wt.%), limestone crushing waste (4-9 wt.%) and dry hyper plasticizer (0.2 wt.%) has been created. It can be used in the building materials industry for production of high-strength concrete. The composite binder is obtained by co-milling of the components in vario-planetary mill to a specific surface area of 550-600 m2/kg. The technical result is the possibility of obtaining a composite binder with significant replacement of cement with industrial waste, cost-effective and superior to portland cement for construction and technical properties, increased activity. This allows producing concrete for walling with a compressive strength of 100 MPa, while using more than 50% of industrial waste.

  16. Impacts of oxidative stress on acetylcholinesterase transcription, and activity in embryos of zebrafish (Danio rerio) following Chlorpyrifos exposure.

    PubMed

    Rodríguez-Fuentes, Gabriela; Rubio-Escalante, Fernando J; Noreña-Barroso, Elsa; Escalante-Herrera, Karla S; Schlenk, Daniel

    2015-01-01

    Organophosphate pesticides cause irreversible inhibition of AChE which leads to neuronal overstimulation and death. Thus, dogma indicates that the target of OP pesticides is AChE, but many authors postulate that these compounds also disturb cellular redox processes, and change the activities of antioxidant enzymes. Interestingly, it has also been reported that oxidative stress plays also a role in the regulation and activity of AChE. The aims of this study were to determine the effects of the antioxidant, vitamin C (VC), the oxidant, t-butyl hydroperoxide (tBOOH) and the organophosphate Chlorpyrifos (CPF), on AChE gene transcription and activity in zebrafish embryos after 72h exposure. In addition, oxidative stress was evaluated by measuring antioxidant enzymes activities and transcription, and quantification of total glutathione. Apical effects on the development of zebrafish embryos were also measured. With the exception of AChE inhibition and enhanced gene expression, limited effects of CPF on oxidative stress and apical endpoints were found at this developmental stage. Addition of VC had little effect on oxidative stress or AChE, but increased pericardial area and heartbeat rate through an unknown mechanism. TBOOH diminished AChE gene expression and activity, and caused oxidative stress when administered alone. However, in combination with CPF, only reductions in AChE activity were observed with no significant changes in oxidative stress suggesting the adverse apical endpoints in the embryos may have been due to AChE inhibition by CPF rather than oxidative stress. These results give additional evidence to support the role of prooxidants in AChE activity and expression.

  17. Chlorpyrifos and chlorpyrifos-oxon inhibit axonal growth by interfering with the morphogenic activity of acetylcholinesterase

    SciTech Connect

    Yang Dongren; Howard, Angela; Bruun, Donald; Ajua-Alemanj, Mispa; Pickart, Cecile; Lein, Pamela J.

    2008-04-01

    A primary role of acetylcholinesterase (AChE) is regulation of cholinergic neurotransmission by hydrolysis of synaptic acetylcholine. In the developing nervous system, however, AChE also functions as a morphogenic factor to promote axonal growth. This raises the question of whether organophosphorus pesticides (OPs) that are known to selectively bind to and inactivate the enzymatic function of AChE also interfere with its morphogenic function to perturb axonogenesis. To test this hypothesis, we exposed primary cultures of sensory neurons derived from embryonic rat dorsal root ganglia (DRG) to chlorpyrifos (CPF) or its oxon metabolite (CPFO). Both OPs significantly decreased axonal length at concentrations that had no effect on cell viability, protein synthesis or the enzymatic activity of AChE. Comparative analyses of the effects of CPF and CPFO on axonal growth in DRG neurons cultured from AChE nullizygous (AChE{sup -/-}) versus wild type (AChE{sup +/+}) mice indicated that while these OPs inhibited axonal growth in AChE{sup +/+} DRG neurons, they had no effect on axonal growth in AChE{sup -/-} DRG neurons. However, transfection of AChE{sup -/-} DRG neurons with cDNA encoding full-length AChE restored the wild type response to the axon inhibitory effects of OPs. These data indicate that inhibition of axonal growth by OPs requires AChE, but the mechanism involves inhibition of the morphogenic rather than enzymatic activity of AChE. These findings suggest a novel mechanism for explaining not only the functional deficits observed in children and animals following developmental exposure to OPs, but also the increased vulnerability of the developing nervous system to OPs.

  18. An acetylcholinesterase (AChE) biosensor with enhanced solvent resistance based on chitosan for the detection of pesticides.

    PubMed

    Warner, John; Andreescu, Silvana

    2016-01-01

    Solvent tolerance of immobilized enzymes is important for many biosensing and biotechnological applications. In this paper we report an acetylcholinesterase (AChE) biosensor based on chitosan that exhibits high solvent resistance and enables sensitive detection of pesticides in presence of a high content of organic solvents. The solvent effect was established comparatively for the enzyme immobilized in chitosan and covalently cross-linked with glutaraldehyde. The activity of the immobilized AChE was dependent on the immobilization method and solvent type. The enzyme entrapped in chitosan fully conserved its activity in up to 25% methanol, 15% acetonitrile and 100% cyclohexane while the enzyme cross-linked with glutaraldehyde gradually lost its activity starting at 5% acetonitrile and methanol, and showed variable levels in cyclohexane. The detection limits of the biosensor for paraoxon were: 7.5 nM in 25% methanol, 100 nM in 15% acetonitrile and 2.5 μM in 100% cyclohexane. This study demonstrates that chitosan provides an excellent immobilization environment for AChE biosensors designed to operate in environments containing high amounts of organic solvents. It also highlights the effect of the immobilization material and solvent type on enzyme stability. These findings can enable future selection of the immobilization matrix and solvent type for the development of organic phase enzyme based systems.

  19. Contribution of α4β2 nAChR in nicotine-induced intracellular calcium response and excitability of MSDB neurons.

    PubMed

    Wang, Jiangang; Wang, Yali; Wang, Yang; Wang, Ran; Zhang, Yunpeng; Zhang, Qian; Lu, Chengbiao

    2014-12-10

    The neurons of medial septal diagonal band of broca (MSDB) project to hippocampus and play an important role in MSDB-hippocampal synaptic transmission, plasticity and network oscillation. Nicotinic acetylcholine receptor (nAChR) subunits, α4β2 and α7 nAChRs, are expressed in MSDB neurons and permeable to calcium ions, which may modulate the function of MSDB neurons. The aims of this study are to determine the roles of selective nAChR activation on the calcium responses and membrane currents in MSDB neurons. Our results showed that nicotine increased calcium responses in the majority of MSDB neurons, pre-treatment of MSDB slices with a α4β2 nAChR antagonist, DhβE but not a α7 nAChR antagonist, MLA prevented nicotine-induced calcium responses. The whole cell patch clamp recordings showed that nicotine-induced inward current and acetylcholine (ACh) induced-firing activity can be largely reduced or prevented by DhβE in MSDB neurons. Surprisingly, post-treatment of α4β2 or α7 nAChR antagonists failed to block nicotine׳s role, they increased calcium responses instead. Application of calcium chelator EGTA reduced calcium responses in all neurons tested. These results suggest that there was a subtype specific modulation of nAChRs on calcium signaling and membrane currents in MSDB neurons and nAChR antagonists were also able to induce calcium responses involving a distinct mechanism.

  20. Treatment with endotracheal therapeutics after sarin microinstillation inhalation exposure increases blood cholinesterase levels in guinea pigs.

    PubMed

    Che, Magnus M; Song, Jian; Oguntayo, Samuel; Doctor, Bhupendra P; Rezk, Peter; Perkins, Michael W; Sciuto, Alfred M; Nambiar, Madhusoodana P

    2012-05-01

    Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities were measured in the blood and tissues of animals that are treated with a number of endotracheally aerosolized therapeutics for protection against inhalation toxicity to sarin. Therapeutics included, aerosolized atropine methyl bromide (AMB), scopolamine or combination of AMB with salbutamol, sphingosine 1-phosphate, keratinocyte growth factor, adenosine A1 receptor antisense oligonucleotide (EPI2010), 2,3-diacetyloxybenzoic acid (2,3 DABA), oxycyte, and survanta. Guinea pigs exposed to 677.4 mg/m(3) or 846.5 mg/m(3) (1.2 LCt(50)) sarin for 4 min using a microinstillation inhalation exposure technique and treated 1 min later with the aerosolized therapeutics. Treatment with all therapeutics significantly increased the survival rate with no convulsions throughout the 24 h study period. Blood AChE activity determined using acetylthiocholine as substrate showed 20% activity remaining in sarin-exposed animals compare to controls. In aerosolized AMB and scopolamine-treated animals the remaining AChE activity was significantly higher (45-60%) compared to sarin-exposed animals (p < 0.05). Similarly, treatment with all the combination therapeutics resulted in significant increase in blood AChE activity in comparison to sarin-exposed animals although the increases varied between treatments (p < 0.05). BChE activity was increased after treatment with aerosolized therapeutics but was lesser in magnitude compared to AChE activity changes. Various tissues showed elevated AChE activity after therapeutic treatment of sarin-exposed animals. Increased AChE and BChE activities in animals treated with nasal therapeutics suggest that enhanced breathing and reduced respiratory toxicity/lung injury possibly contribute to rapid normalization of chemical warfare nerve agent inhibited cholinesterases.

  1. Functional Analysis and Molecular Docking studies of Medicinal Compounds for AChE and BChE in Alzheimer’s Disease and Type 2 Diabetes Mellitus

    PubMed Central

    Kaladhar, Dowluru SVGK; Yarla, Nagendra Sastry; Anusha, N.

    2013-01-01

    Acetylcholinesterase and Butyrylcholinesterase share unravelling link with components of metabolic syndromes that’s characterised by low levels of HDL cholesterol, obesity, high fast aldohexose levels, hyper-trigliceridaemia and high blood pressure, by regulation of cholinergic transmission and therefore the enzyme activity within a living system. The phosphomotifs associated with amino acid and tyrosine binding motifs in AChE and BChE were known to be common. Phylogenetic tree was constructed to these proteins usinf UPGMA and Maximum Likelihood methods in MEGA software has shown interaction of AChE and BChE with ageing diseases like Alzheimer’s disease and Diabetes. AChE has shown closely related to BChE, retinol dehydrogenase and β-polypeptide. The present studies is also accomplished that AChE, BChE, COLQ, HAND1, APP, NLGN2 and NGF proteins has interactions with diseases such as Alzheimer’s and D2M using Pathwaylinker and STRING. Medicinal compounds like Ortho-7, Dibucaine and HI-6 are predicted as good targets for modeled AChE and BChE proteins based on docking studies. Hence perceptive studies of cholinesterase structure and the biological mechanisms of inhibition are necessary for effective drug development. PMID:23936743

  2. Neurophysiological predictors of long term response to AChE inhibitors in AD patients

    PubMed Central

    Di, L; Oliviero, A; Pilato, F; Saturno, E; Dileone, M; Marra, C; Ghirlanda, S; Ranieri, F; Gainotti, G; Tonali, P

    2005-01-01

    Background: In vivo evaluation of cholinergic circuits of the human brain has recently been introduced using a transcranial magnetic stimulation (TMS) protocol based on coupling peripheral nerve stimulation with motor cortex TMS (short latency afferent inhibition, SAI). SAI is reduced in Alzheimer's disease (AD) and drugs enhancing cholinergic transmission increase SAI. Methods: We evaluated whether SAI testing, together with SAI test-retest, after a single dose of the acetylcholinesterase (AChE) inhibitor rivastigmine, might be useful in predicting the response after 1 year treatment with rivastigmine in 16 AD patients. Results: Fourteen AD patients had pathologically reduced SAI. SAI was increased after administration of a single oral dose of rivastigmine in AD patients with abnormal baseline SAI, but individual responses to rivastigmine varied widely, with SAI change ranging from an increase in inhibition of ∼50% of test size to no change. Baseline SAI and the increase in SAI after a single dose of rivastigmine were correlated with response to long term treatment. A normal SAI in baseline conditions, or an abnormal SAI in baseline conditions that was not greatly increased by a single oral dose of rivastigmine, were invariably associated with poor response to long term treatment, while an abnormal SAI in baseline conditions in conjunction with a large increase in SAI after a single dose of rivastigmine was associated with good response to long term treatment in most of the patients. Conclusions: Evaluation of SAI may be useful for identifying AD patients likely to respond to treatment with AChE inhibitors. PMID:16024879

  3. Effects of T-82, a new quinoline derivative, on cholinesterase activity and extracellular acetylcholine concentration in rat brain.

    PubMed

    Isoma, Kazuo; Ishikawa, Masago; Ohta, Megumi; Ogawa, Yoichiro; Hasegawa, Hiroshi; Kohda, Tadayuki; Kamei, Junzo

    2002-02-01

    The effects of T-82 (2-[2-(1-benzylpiperidin-4-yl)ethyl]-2,3-dihydro-9-methoxy-1H-pyrrolo [3,4-b]quinolin-1-one hemifumarate), a new quinoline derivative, on acetylcholinesterase (AChE) activity and acetylcholine (ACh) release were compared with those of the well-known cholinesterase inhibitors tacrine and E2020. T-82, tacrine and E2020 all concentration-dependently inhibited AChE in rat brain homogenate (IC50 = 109.4, 84.2 and 11.8 nM, respectively). In addition, although tacrine strongly inhibited butyrylcholinesterase (BuChE), T-82 and E2020 showed only weak activity on BuChE in human plasma. In ex vivo experiments, intraperitoneal administration of T-82 at a dose of 30 mg/kg inhibited AChE activity in the hippocampus, frontal cortex and parietal cortex of rats. The effect of T-82 on the extracellular ACh concentration in rat brain was measured using in vivo microdialysis. T-82 at doses of 10 and 30 mg/kg, i.p. increased the extracellular ACh concentration in the hippocampus and striatum in a dose-dependent manner. These findings suggest that T-82 activates the central cholinergic system by selectively inhibiting AChE activity, while weakly affecting peripheral BuChE activity, and that T-82 increases the extracellular ACh concentration in the brain, which is followed by inhibited AChE activity.

  4. Differential effects of lysophosphatidylcholine and ACh on muscarinic K+, non-selective cation and Ca2+ currents in guinea-pig atrial cells

    PubMed Central

    Li, Libing; Matsuoka, Isao; Sakamoto, Kazuho; Kimura, Junko

    2016-01-01

    Abstract We compared the effects of lysophosphatidylcholine (LPC) and acetylcholine (ACh) on IK(ACh), ICa and a non-selective cation current (INSC) in guinea-pig atrial myocytes to clarify whether LPC and ACh activate similar Gi/o-coupled effector systems. IK(ACh), ICa and INSC were analyzed in single atrial myocytes by the whole cell patch-clamp. LPC induced INSC in a concentration-dependent manner in atrial cells. ACh activated IK(ACh), but failed to evoke INSC. LPC also activated IK(ACh) but with significantly less potency than ACh. The effects of both ligands on IK(ACh) were inhibited by intracellular loading of pre-activated PTX. This treatment also inhibited LPC-induced INSC, indicating that IK(ACh) and INSC induced by LPC are both mediated by Gi/o. LPC and ACh had similar potencies in inhibiting ICa, which was pre-augmented by forskolin, indicating that LPC and ACh activate similar amounts of α-subunits of Gi/o. The different effects of LPC and ACh on IK(ACh) and INSC may suggest that LPC and ACh activate Gi/o having different types of βγ subunits, and that LPC-induced INSC may be mediated by βγ subunits of Gi/o, which are less effective in inducing IK(ACh). PMID:26911304

  5. Increasing opportunities for physical activity.

    PubMed

    Buckley, Sue

    2007-07-01

    Being physically active can have a number of benefits - having fun, meeting with friends, keeping healthy and experiencing success. For children with Down syndrome the foundations need to be laid early if they are to keep active in school, teenage and adult years and parents ask for more help in this area from professionals.

  6. Intensified vmPFC surveillance over PTSS under perturbed microRNA-608/AChE interaction.

    PubMed

    Lin, T; Simchovitz, A; Shenhar-Tsarfaty, S; Vaisvaser, S; Admon, R; Hanin, G; Hanan, M; Kliper, E; Bar-Haim, Y; Shomron, N; Fernandez, G; Lubin, G; Fruchter, E; Hendler, T; Soreq, H

    2016-05-03

    Trauma causes variable risk of posttraumatic stress symptoms (PTSS) owing to yet-unknown genome-neuronal interactions. Here, we report co-intensified amygdala and ventromedial prefrontal cortex (vmPFC) emotional responses that may overcome PTSS in individuals with the single-nucleotide polymorphism (SNP) rs17228616 in the acetylcholinesterase (AChE) gene. We have recently shown that in individuals with the minor rs17228616 allele, this SNP interrupts AChE suppression by microRNA (miRNA)-608, leading to cortical elevation of brain AChE and reduced cortisol and the miRNA-608 target GABAergic modulator CDC42, all stress-associated. To examine whether this SNP has effects on PTSS and threat-related brain circuits, we exposed 76 healthy Israel Defense Forces soldiers who experienced chronic military stress to a functional magnetic resonance imaging task of emotional and neutral visual stimuli. Minor allele individuals predictably reacted to emotional stimuli by hyperactivated amygdala, a hallmark of PTSS and a predisposing factor of posttraumatic stress disorder (PTSD). Despite this, minor allele individuals showed no difference in PTSS levels. Mediation analyses indicated that the potentiated amygdala reactivity in minor allele soldiers promoted enhanced vmPFC recruitment that was associated with their limited PTSS. Furthermore, we found interrelated expression levels of several miRNA-608 targets including CD44, CDC42 and interleukin 6 in human amygdala samples (N=7). Our findings suggest that miRNA-608/AChE interaction is involved in the threat circuitry and PTSS and support a model where greater vmPFC regulatory activity compensates for amygdala hyperactivation in minor allele individuals to neutralize their PTSS susceptibility.

  7. Intensified vmPFC surveillance over PTSS under perturbed microRNA-608/AChE interaction

    PubMed Central

    Lin, T; Simchovitz, A; Shenhar-Tsarfaty, S; Vaisvaser, S; Admon, R; Hanin, G; Hanan, M; Kliper, E; Bar-Haim, Y; Shomron, N; Fernandez, G; Lubin, G; Fruchter, E; Hendler, T; Soreq, H

    2016-01-01

    Trauma causes variable risk of posttraumatic stress symptoms (PTSS) owing to yet-unknown genome–neuronal interactions. Here, we report co-intensified amygdala and ventromedial prefrontal cortex (vmPFC) emotional responses that may overcome PTSS in individuals with the single-nucleotide polymorphism (SNP) rs17228616 in the acetylcholinesterase (AChE) gene. We have recently shown that in individuals with the minor rs17228616 allele, this SNP interrupts AChE suppression by microRNA (miRNA)-608, leading to cortical elevation of brain AChE and reduced cortisol and the miRNA-608 target GABAergic modulator CDC42, all stress-associated. To examine whether this SNP has effects on PTSS and threat-related brain circuits, we exposed 76 healthy Israel Defense Forces soldiers who experienced chronic military stress to a functional magnetic resonance imaging task of emotional and neutral visual stimuli. Minor allele individuals predictably reacted to emotional stimuli by hyperactivated amygdala, a hallmark of PTSS and a predisposing factor of posttraumatic stress disorder (PTSD). Despite this, minor allele individuals showed no difference in PTSS levels. Mediation analyses indicated that the potentiated amygdala reactivity in minor allele soldiers promoted enhanced vmPFC recruitment that was associated with their limited PTSS. Furthermore, we found interrelated expression levels of several miRNA-608 targets including CD44, CDC42 and interleukin 6 in human amygdala samples (N=7). Our findings suggest that miRNA-608/AChE interaction is involved in the threat circuitry and PTSS and support a model where greater vmPFC regulatory activity compensates for amygdala hyperactivation in minor allele individuals to neutralize their PTSS susceptibility. PMID:27138800

  8. The brain metabolite kynurenic acid inhibits alpha7 nicotinic receptor activity and increases non-alpha7 nicotinic receptor expression: physiopathological implications.

    PubMed

    Hilmas, C; Pereira, E F; Alkondon, M; Rassoulpour, A; Schwarcz, R; Albuquerque, E X

    2001-10-01

    The tryptophan metabolite kynurenic acid (KYNA) has long been recognized as an NMDA receptor antagonist. Here, interactions between KYNA and the nicotinic system in the brain were investigated using the patch-clamp technique and HPLC. In the electrophysiological studies, agonists were delivered via a U-shaped tube, and KYNA was applied in admixture with agonists and via the background perfusion. Exposure (>/=4 min) of cultured hippocampal neurons to KYNA (>/=100 nm) inhibited activation of somatodendritic alpha7 nAChRs; the IC(50) for KYNA was approximately 7 microm. The inhibition of alpha7 nAChRs was noncompetitive with respect to the agonist and voltage independent. The slow onset of this effect could not be accounted for by an intracellular action because KYNA (1 mm) in the pipette solution had no effect on alpha7 nAChR activity. KYNA also blocked the activity of preterminal/presynaptic alpha7 nAChRs in hippocampal neurons in cultures and in slices. NMDA receptors were less sensitive than alpha7 nAChRs to KYNA. The IC(50) values for KYNA-induced blockade of NMDA receptors in the absence and presence of glycine (10 microm) were approximately 15 and 235 microm, respectively. Prolonged (3 d) exposure of cultured hippocampal neurons to KYNA increased their nicotinic sensitivity, apparently by enhancing alpha4beta2 nAChR expression. Furthermore, as determined by HPLC with fluorescence detection, repeated systemic treatment of rats with nicotine caused a transient reduction followed by an increase in brain KYNA levels. These results demonstrate that nAChRs are targets for KYNA and suggest a functionally significant cross talk between the nicotinic cholinergic system and the kynurenine pathway in the brain.

  9. Nicotinic Acetylcholine Receptor (nAChR) Dependent Chorda Tympani Taste Nerve Responses to Nicotine, Ethanol and Acetylcholine.

    PubMed

    Ren, Zuo Jun; Mummalaneni, Shobha; Qian, Jie; Baumgarten, Clive M; DeSimone, John A; Lyall, Vijay

    2015-01-01

    Nicotine elicits bitter taste by activating TRPM5-dependent and TRPM5-independent but neuronal nAChR-dependent pathways. The nAChRs represent common targets at which acetylcholine, nicotine and ethanol functionally interact in the central nervous system. Here, we investigated if the nAChRs also represent a common pathway through which the bitter taste of nicotine, ethanol and acetylcholine is transduced. To this end, chorda tympani (CT) taste nerve responses were monitored in rats, wild-type mice and TRPM5 knockout (KO) mice following lingual stimulation with nicotine free base, ethanol, and acetylcholine, in the absence and presence of nAChR agonists and antagonists. The nAChR modulators: mecamylamine, dihydro-β-erythroidine, and CP-601932 (a partial agonist of the α3β4* nAChR), inhibited CT responses to nicotine, ethanol, and acetylcholine. CT responses to nicotine and ethanol were also inhibited by topical lingual application of 8-chlorophenylthio (CPT)-cAMP and loading taste cells with [Ca2+]i by topical lingual application of ionomycin + CaCl2. In contrast, CT responses to nicotine were enhanced when TRC [Ca2+]i was reduced by topical lingual application of BAPTA-AM. In patch-clamp experiments, only a subset of isolated rat fungiform taste cells exposed to nicotine responded with an increase in mecamylamine-sensitive inward currents. We conclude that nAChRs expressed in a subset of taste cells serve as common receptors for the detection of the TRPM5-independent bitter taste of nicotine, acetylcholine and ethanol.

  10. Nicotinic Acetylcholine Receptor (nAChR) Dependent Chorda Tympani Taste Nerve Responses to Nicotine, Ethanol and Acetylcholine

    PubMed Central

    Ren, Zuo Jun; Mummalaneni, Shobha; Qian, Jie; Baumgarten, Clive M.; DeSimone, John A.; Lyall, Vijay

    2015-01-01

    Nicotine elicits bitter taste by activating TRPM5-dependent and TRPM5-independent but neuronal nAChR-dependent pathways. The nAChRs represent common targets at which acetylcholine, nicotine and ethanol functionally interact in the central nervous system. Here, we investigated if the nAChRs also represent a common pathway through which the bitter taste of nicotine, ethanol and acetylcholine is transduced. To this end, chorda tympani (CT) taste nerve responses were monitored in rats, wild-type mice and TRPM5 knockout (KO) mice following lingual stimulation with nicotine free base, ethanol, and acetylcholine, in the absence and presence of nAChR agonists and antagonists. The nAChR modulators: mecamylamine, dihydro-β-erythroidine, and CP-601932 (a partial agonist of the α3β4* nAChR), inhibited CT responses to nicotine, ethanol, and acetylcholine. CT responses to nicotine and ethanol were also inhibited by topical lingual application of 8-chlorophenylthio (CPT)-cAMP and loading taste cells with [Ca2+]i by topical lingual application of ionomycin + CaCl2. In contrast, CT responses to nicotine were enhanced when TRC [Ca2+]i was reduced by topical lingual application of BAPTA-AM. In patch-clamp experiments, only a subset of isolated rat fungiform taste cells exposed to nicotine responded with an increase in mecamylamine-sensitive inward currents. We conclude that nAChRs expressed in a subset of taste cells serve as common receptors for the detection of the TRPM5-independent bitter taste of nicotine, acetylcholine and ethanol. PMID:26039516

  11. Synaptosomal acetylcholinesterase activity variation pattern in the presence of electromagnetic fields.

    PubMed

    Afrasiabi, Ali; Riazi, Gholam Hossein; Abbasi, Shayan; Dadras, Ali; Ghalandari, Behafarid; Seidkhani, Hossein; Modaresi, Seyed Mohamad Sadegh; Masoudian, Neda; Amani, Amir; Ahmadian, Shahin

    2014-04-01

    Acetylcholinesterase (AChE) is the enzyme that controls the acetylcholine (ACh) concentrations in cholinergic synaptic clefts by hydrolyzing ACh to choline and acetate. Cholinergic synapses are involved in important functions such as learning, memory and cognition. In this study, we investigated the effects of a wide range of extremely low frequency electromagnetic fields (ELF-EMFs) on synaptic ACh concentrations through AChE enzyme activity assay. Synaptosome suspensions were prepared as a neural terminus from cerebral cortex of sheep brain. Prepared synaptosomes were exposed to ELF-EMFs with frequency ranging from 50 Hz to 230 Hz for duration between 15 and 120 min and flux intensity between 0.1 mT and 1.7 mT. Consequently, AChE activity was measured by Ellman method. Raw data were analyzed by neural network based software, Inform 4.02, to predict AChE activity pattern through nine 3D curves. These curves showed that AChE activity decreases when exposed to ELF-EMFs of 1.2 mT to 1.7 mT intensity and 50 Hz to 90 Hz frequency. Thus, it is proposed that exposure to fields of in this range of frequency-intensity would be effective in clinical treatments of cholinergic disorders to increase synaptic ACh concentration. However, more in vivo experiments are needed to develop this suggested treatment.

  12. Increasing Youth Physical Activity with Activity Calendars

    ERIC Educational Resources Information Center

    Eckler, Seth

    2016-01-01

    Physical educators often struggle with ways to get their students to be active beyond the school day. One strategy to accomplish this is the use of physical activity calendars (PACs). The purpose of this article is to support the use of PACs and give practical advice for creating effective PACs.

  13. Design, Synthesis, and Evaluation of Donepezil-Like Compounds as AChE and BACE-1 Inhibitors.

    PubMed

    Costanzo, Paola; Cariati, Luca; Desiderio, Doriana; Sgammato, Roberta; Lamberti, Anna; Arcone, Rosaria; Salerno, Raffaele; Nardi, Monica; Masullo, Mariorosario; Oliverio, Manuela

    2016-05-12

    An ecofriendly synthetic pathway for the synthesis of donepezil precursors is described. Alternative energy sources were used for the total synthesis in order to improve yields, regioselectively, and rate of each synthetic step and to reduce the coproduction of waste at the same time. For all products, characterized by an improved structural rigidity respect to donepezil, the inhibitor activity on AChE, the selectivity vs BuChE, the side-activity on BACE-1, and the effect on SHSY-5Y neuroblastoma cells viability were tested. Two potential new lead compounds for a dual therapeutic strategy against Alzheimer's disease were envisaged.

  14. Muscarinic ACh Receptors Contribute to Aversive Olfactory Learning in Drosophila

    PubMed Central

    Silva, Bryon; Molina-Fernández, Claudia; Ugalde, María Beatriz; Tognarelli, Eduardo I.; Angel, Cristian; Campusano, Jorge M.

    2015-01-01

    The most studied form of associative learning in Drosophila consists in pairing an odorant, the conditioned stimulus (CS), with an unconditioned stimulus (US). The timely arrival of the CS and US information to a specific Drosophila brain association region, the mushroom bodies (MB), can induce new olfactory memories. Thus, the MB is considered a coincidence detector. It has been shown that olfactory information is conveyed to the MB through cholinergic inputs that activate acetylcholine (ACh) receptors, while the US is encoded by biogenic amine (BA) systems. In recent years, we have advanced our understanding on the specific neural BA pathways and receptors involved in olfactory learning and memory. However, little information exists on the contribution of cholinergic receptors to this process. Here we evaluate for the first time the proposition that, as in mammals, muscarinic ACh receptors (mAChRs) contribute to memory formation in Drosophila. Our results show that pharmacological and genetic blockade of mAChRs in MB disrupts olfactory aversive memory in larvae. This effect is not explained by an alteration in the ability of animals to respond to odorants or to execute motor programs. These results show that mAChRs in MB contribute to generating olfactory memories in Drosophila. PMID:26380118

  15. Escherichia coli Protein Expression System for Acetylcholine Binding Proteins (AChBPs)

    PubMed Central

    Abraham, Nikita; Paul, Blessy; Ragnarsson, Lotten; Lewis, Richard J.

    2016-01-01

    Nicotinic acetylcholine receptors (nAChR) are ligand gated ion channels, identified as therapeutic targets for a range of human diseases. Drug design for nAChR related disorders is increasingly using structure-based approaches. Many of these structural insights for therapeutic lead development have been obtained from co-crystal structures of nAChR agonists and antagonists with the acetylcholine binding protein (AChBP). AChBP is a water soluble, structural and functional homolog of the extracellular, ligand-binding domain of nAChRs. Currently, AChBPs are recombinantly expressed in eukaryotic expression systems for structural and biophysical studies. Here, we report the establishment of an Escherichia coli (E. coli) expression system that significantly reduces the cost and time of production compared to the existing expression systems. E. coli can efficiently express unglycosylated AChBP for crystallography and makes the expression of isotopically labelled forms feasible for NMR. We used a pHUE vector containing an N-terminal His-tagged ubiquitin fusion protein to facilitate AChBP expression in the soluble fractions, and thus avoid the need to recover protein from inclusion bodies. The purified protein yield obtained from the E. coli expression system is comparable to that obtained from existing AChBP expression systems. E. coli expressed AChBP bound nAChR agonists and antagonists with affinities matching those previously reported. Thus, the E. coli expression system significantly simplifies the expression and purification of functional AChBP for structural and biophysical studies. PMID:27304486

  16. Novel bis-(−)-nor-meptazinol derivatives act as dual binding site AChE inhibitors with metal-complexing property

    SciTech Connect

    Zheng, Wei; Li, Juan; Qiu, Zhuibai; Xia, Zheng; Li, Wei; Yu, Lining; Chen, Hailin; Chen, Jianxing; Chen, Yan; Hu, Zhuqin; Zhou, Wei; Shao, Biyun; Cui, Yongyao; Xie, Qiong; Chen, Hongzhuan

    2012-10-01

    The strategy of dual binding site acetylcholinesterase (AChE) inhibition along with metal chelation may represent a promising direction for multi-targeted interventions in the pathophysiological processes of Alzheimer's disease (AD). In the present study, two derivatives (ZLA and ZLB) of a potent dual binding site AChE inhibitor bis-(−)-nor-meptazinol (bis-MEP) were designed and synthesized by introducing metal chelating pharmacophores into the middle chain of bis-MEP. They could inhibit human AChE activity with IC{sub 50} values of 9.63 μM (for ZLA) and 8.64 μM (for ZLB), and prevent AChE-induced amyloid-β (Aβ) aggregation with IC{sub 50} values of 49.1 μM (for ZLA) and 55.3 μM (for ZLB). In parallel, molecular docking analysis showed that they are capable of interacting with both the catalytic and peripheral anionic sites of AChE. Furthermore, they exhibited abilities to complex metal ions such as Cu(II) and Zn(II), and inhibit Aβ aggregation triggered by these metals. Collectively, these results suggest that ZLA and ZLB may act as dual binding site AChEIs with metal-chelating potency, and may be potential leads of value for further study on disease-modifying treatment of AD. -- Highlights: ► Two novel bis-(−)-nor-meptazinol derivatives are designed and synthesized. ► ZLA and ZLB may act as dual binding site AChEIs with metal-chelating potency. ► They are potential leads for disease-modifying treatment of Alzheimer's disease.

  17. In silico studies in probing the role of kinetic and structural effects of different drugs for the reactivation of tabun-inhibited AChE.

    PubMed

    Lo, Rabindranath; Chandar, Nellore Bhanu; Kesharwani, Manoj K; Jain, Aastha; Ganguly, Bishwajit

    2013-01-01

    We have examined the reactivation mechanism of the tabun-conjugated AChE with various drugs using density functional theory (DFT) and post-Hartree-Fock methods. The electronic environments and structural features of neutral oximes (deazapralidoxime and 3-hydroxy-2-pyridinealdoxime) and charged monopyridinium oxime (2-PAM) and bispyridinium oxime (Ortho-7) are different, hence their efficacy varies towards the reactivation process of tabun-conjugated AChE. The calculated potential energy surfaces suggest that a monopyridinium reactivator is less favorable for the reactivation of tabun-inhibited AChE compared to a bis-quaternary reactivator, which substantiates the experimental study. The rate determining barrier with neutral oximes was found to be ∼2.5 kcal/mol, which was ∼5.0 kcal/mol lower than charged oxime drugs such as Ortho-7. The structural analysis of the calculated geometries suggest that the charged oximes form strong O(…)H and N(…)H hydrogen bonding and C-H(…)π non-bonding interaction with the tabun-inhibited enzyme to stabilize the reactant complex compared to separated reactants, which influences the activation barrier. The ability of neutral drugs to cross the blood-brain barrier was also found to be superior to charged antidotes, which corroborates the available experimental observations. The calculated activation barriers support the superiority of neutral oximes for the activation of tabun-inhibited AChE compared to charged oximes. However, they lack effective interactions with their peripheral sites. Docking studies revealed that the poor binding affinity of simple neutral oxime drugs such as 3-hydroxy-2-pyridinealdoxime inside the active-site gorge of AChE was significantly augmented with the addition of neutral peripheral units compared to conventional charged peripheral sites. The newly designed oxime drug 2 appears to be an attractive candidate as efficient antidote to kinetically and structurally reactivate the tabun

  18. In Silico Studies in Probing the Role of Kinetic and Structural Effects of Different Drugs for the Reactivation of Tabun-Inhibited AChE

    PubMed Central

    Lo, Rabindranath; Chandar, Nellore Bhanu; Kesharwani, Manoj K.; Jain, Aastha; Ganguly, Bishwajit

    2013-01-01

    We have examined the reactivation mechanism of the tabun-conjugated AChE with various drugs using density functional theory (DFT) and post-Hartree-Fock methods. The electronic environments and structural features of neutral oximes (deazapralidoxime and 3-hydroxy-2-pyridinealdoxime) and charged monopyridinium oxime (2-PAM) and bispyridinium oxime (Ortho-7) are different, hence their efficacy varies towards the reactivation process of tabun-conjugated AChE. The calculated potential energy surfaces suggest that a monopyridinium reactivator is less favorable for the reactivation of tabun-inhibited AChE compared to a bis-quaternary reactivator, which substantiates the experimental study. The rate determining barrier with neutral oximes was found to be ∼2.5 kcal/mol, which was ∼5.0 kcal/mol lower than charged oxime drugs such as Ortho-7. The structural analysis of the calculated geometries suggest that the charged oximes form strong O…H and N…H hydrogen bonding and C-H…π non-bonding interaction with the tabun-inhibited enzyme to stabilize the reactant complex compared to separated reactants, which influences the activation barrier. The ability of neutral drugs to cross the blood-brain barrier was also found to be superior to charged antidotes, which corroborates the available experimental observations. The calculated activation barriers support the superiority of neutral oximes for the activation of tabun-inhibited AChE compared to charged oximes. However, they lack effective interactions with their peripheral sites. Docking studies revealed that the poor binding affinity of simple neutral oxime drugs such as 3-hydroxy-2-pyridinealdoxime inside the active-site gorge of AChE was significantly augmented with the addition of neutral peripheral units compared to conventional charged peripheral sites. The newly designed oxime drug 2 appears to be an attractive candidate as efficient antidote to kinetically and structurally reactivate the tabun-inhibited enzyme

  19. Nicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone induce cyclooxygenase-2 activity in human gastric cancer cells: Involvement of nicotinic acetylcholine receptor (nAChR) and {beta}-adrenergic receptor signaling pathways

    SciTech Connect

    Shin, Vivian Yvonne; Jin, H.C.; Ng, Enders K.O.; Yu Jun; Leung, W.K.; Cho, C.H.; Sung, J.J.Y.

    2008-12-01

    Induction of cyclooxygenase-2 (COX-2) associates with cigarette smoke exposure in many malignancies. Nicotine and its derivative, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), are the two important components in cigarette smoke that contributes to cancer development. However, the molecular mechanism(s) by which nicotine or NNK promotes gastric carcinogenesis remains largely unknown. We found that nicotine and NNK significantly enhanced cell proliferation in AGS cells that expressed both alpha7 nicotinic acetylcholine receptor ({alpha}7 nAChR) and {beta}-adrenergic receptors. Treatment of cells with {alpha}-bungarotoxin ({alpha}-BTX, {alpha}7nAChR antagonist) or propranolol ({beta}-adrenergic receptor antagonist) blocked NNK-induced COX-2/PGE{sub 2} and cell proliferation, while nicotine-mediated cell growth and COX-2/PGE{sub 2} induction can only be suppressed by propranolol, but not {alpha}-BTX. Moreover, in contrast to the dependence of growth promoting effect of nicotine on Erk activation, inhibitor of p38 mitogen-activated protein kinase (MAPK) repressed NNK-induced COX-2 upregulation and resulted in suppression of cell growth. In addition, nicotine and NNK mediated COX-2 induction via different receptors to modulate several G1/S transition regulatory proteins and promote gastric cancer cell growth. Selective COX-2 inhibitor (SC-236) caused G1 arrest and abrogated nicotine/NNK-induced cell proliferation. Aberrant expression of cyclin D1 and other G1 regulatory proteins are reversed by blockade of COX-2. These results pointed to the importance of adrenergic and nicotinic receptors in gastric tumor growth through MAPK/COX-2 activation, which may perhaps provide a chemoprevention strategy for cigarette smoke-related gastric carcinogenesis.

  20. The effects of 3,4-methylenedioxymethamphetamine (MDMA) on nicotinic receptors: Intracellular calcium increase, calpain/caspase 3 activation, and functional upregulation

    SciTech Connect

    Garcia-Rates, Sara; Camarasa, Jordi

    2010-05-01

    Previous work by our group demonstrated that homomeric alpha7 nicotinic acetylcholine receptors (nAChR) play a role in the neurotoxicity induced by 3,4-methylenedioxymethamphetamine (MDMA), as well as the binding affinity of this drug to these receptors. Here we studied the effect of MDMA on the activation of nAChR subtypes, the consequent calcium mobilization, and calpain/caspase 3 activation because prolonged Ca{sup 2+} increase could contribute to cytotoxicity. As techniques, we used fluorimetry in Fluo-4-loaded PC12 cells and electrophysiology in Xenopus oocytes. MDMA produced a rapid and sustained increase in calcium without reaching the maximum effect induced by ACh. It also concentration-dependently inhibited the response induced by ACh, nicotine, and the specific alpha7 agonist PNU 282987 with IC{sub 50} values in the low micromolar range. Similarly, MDMA induced inward currents in Xenopus oocytes transfected with human alpha7 but not with alpha4beta2 nAChR and inhibited ACh-induced currents in both receptors in a concentration-dependent manner. The calcium response was inhibited by methyllycaconitine (MLA) and alpha-bungarotoxin but not by dihydro-beta-erythroidine. These results therefore indicate that MDMA acts as a partial agonist on alpha7 nAChRs and as an antagonist on the heteromeric subtypes. Subsequently, calcium-induced Ca{sup 2+} release from the endoplasmic reticulum and entry through voltage-operated calcium channels are also implicated as proved using specific antagonists. In addition, treatment with MDMA for 24 h significantly increased basal Ca{sup 2+} levels and induced an increase in alpha-spectrin breakdown products, which indicates that calpain and caspase 3 were activated. These effects were inhibited by pretreatment with MLA. Moreover, pretreatment with MDMA induced functional upregulation of calcium responses to specific agonists of both heteromeric and alpha7 nAChR. Sustained calcium entry and calpain activation could favor the

  1. The effects of 3,4-methylenedioxymethamphetamine (MDMA) on nicotinic receptors: intracellular calcium increase, calpain/caspase 3 activation, and functional upregulation.

    PubMed

    Garcia-Ratés, Sara; Camarasa, Jordi; Sánchez-García, Ana I; Gandía, Luis; Escubedo, Elena; Pubill, David

    2010-05-01

    Previous work by our group demonstrated that homomeric alpha7 nicotinic acetylcholine receptors (nAChR) play a role in the neurotoxicity induced by 3,4-methylenedioxymethamphetamine (MDMA), as well as the binding affinity of this drug to these receptors. Here we studied the effect of MDMA on the activation of nAChR subtypes, the consequent calcium mobilization, and calpain/caspase 3 activation because prolonged Ca(2+) increase could contribute to cytotoxicity. As techniques, we used fluorimetry in Fluo-4-loaded PC12 cells and electrophysiology in Xenopus oocytes. MDMA produced a rapid and sustained increase in calcium without reaching the maximum effect induced by ACh. It also concentration-dependently inhibited the response induced by ACh, nicotine, and the specific alpha7 agonist PNU 282987 with IC(50) values in the low micromolar range. Similarly, MDMA induced inward currents in Xenopus oocytes transfected with human alpha7 but not with alpha4beta2 nAChR and inhibited ACh-induced currents in both receptors in a concentration-dependent manner. The calcium response was inhibited by methyllycaconitine (MLA) and alpha-bungarotoxin but not by dihydro-beta-erythroidine. These results therefore indicate that MDMA acts as a partial agonist on alpha7 nAChRs and as an antagonist on the heteromeric subtypes. Subsequently, calcium-induced Ca(2+) release from the endoplasmic reticulum and entry through voltage-operated calcium channels are also implicated as proved using specific antagonists. In addition, treatment with MDMA for 24 h significantly increased basal Ca(2+) levels and induced an increase in alpha-spectrin breakdown products, which indicates that calpain and caspase 3 were activated. These effects were inhibited by pretreatment with MLA. Moreover, pretreatment with MDMA induced functional upregulation of calcium responses to specific agonists of both heteromeric and alpha7 nAChR. Sustained calcium entry and calpain activation could favor the activation of Ca(2

  2. The reactivation of tabun-inhibited mutant AChE with Ortho-7: steered molecular dynamics and quantum chemical studies.

    PubMed

    Lo, Rabindranath; Chandar, Nellore Bhanu; Ghosh, Shibaji; Ganguly, Bishwajit

    2016-04-01

    A highly toxic nerve agent, tabun, can inhibit acetylcholinesterase (AChE) at cholinergic sites, which leads to serious cardiovascular complications, respiratory compromise and death. We have examined the structural features of the tabun-conjugated AChE complex with an oxime reactivator, Ortho-7, to provide a strategy for designing new and efficient reactivators. Mutation of mAChE within the choline binding site by Y337A and F338A and its interaction with Ortho-7 has been investigated using steered molecular dynamics (SMD) and quantum chemical methods. The overall study shows that after mutagenesis (Y337A), the reactivator can approach more freely towards the phosphorylated active site of serine without any significant steric hindrance in the presence of tabun compared to the wild type and double mutant. Furthermore, the poor binding of Ortho-7 with the peripheral residues of mAChE in the case of the single mutant compared to that of the wild-type and double mutant (Y337A/F338A) can contribute to better efficacy in the former case. Ortho-7 has formed a greater number of hydrogen bonds with the active site surrounding residues His447 and Phe295 in the case of the single mutant (Y337A), and that stabilizes the drug molecule for an effective reactivation process. The DFT M05-2X/6-31+G(d) level of theory shows that the binding energy of Ortho-7 with the single mutant (Y337A) is energetically more preferred (-19.8 kcal mol(-1)) than the wild-type (-8.1 kcal mol(-1)) and double mutant (Y337A/F338A) (-16.0 kcal mol(-1)). The study reveals that both the orientation of the oxime reactivator for nucleophilic attack and the stabilization of the reactivator at the active site would be crucial for the design of an efficient reactivator.

  3. LWH and ACH Helmet Hardware Study

    DTIC Science & Technology

    2015-11-30

    screws and nuts used with the Light Weight Helmet (LWH) and Advanced Combat Helmet (ACH). The testing included basic dimensional measurements, Rockwell...laboratory tests to characterize the properties of helmet screws and nuts used with the Light Weight Helmet (LWH) and Advanced Combat Helmet (ACH). The

  4. [Achetylcholinesterase (AChE) inhibition and serum lipokines in Alzheimer's disease: friend or foe?].

    PubMed

    Kovacs, Janos; Pakaski, Magdolna; Juhasz, Anna; Feher, Agnes; Drotos, Gergely; Fazekas, Csilla Orsike; Horvath, Tamas Laszlo; Janka, Zoltan; Kalman, Janos

    2012-03-01

    Throughout the natural progression of Alzheimer's disease (AD), the body mass index (BMI) decreases. This is believed to be brought on by the disturbance in the central lipid metabolism, but the exact mechanism is yet unknown. Adipokines (adiponectin, leptin), hormones produced by the adipose tissue, change glucose and lipid metabolism, and have an anorectic effect through increasing energy consumption in the hypothalamus. The goal of our study was to examine donepezil - an acetylcholinesterase inhibitor (AChEI) currently used in AD therapy -, and to what degree it influences the serum adipokine levels and metabolic parameters of AD patients. During the self-evaluation of 26 clinically diagnosed mild to moderate AD patients, therapy with 10 mg/day donepezil was started according to current protocols. We measured serum adiponectin, leptin, LDL, HDL, trigliceride levels, and BMI and ApoE polymorphism at the beginning of our study, and at 3 and 6-months intervals respectively. All data were analyzed with SPSS 17. In comparison with pre-donepezil therapy values, at the third month interval serum adiponectin levels showed an increasing and leptin levels a decreasing tendency. At the six month interval, adiponectin levels significantly increased (p=0.007), leptin levels decreased (p=0.013), BMI (p=0.001) and abdominal circumference (p=0.017) was significantly lower at 6 months as compared to control values. We did not observe any changes in the lipid profile, and ApoE4 allele carrying showed no association with the parameters. To our knowledge, we are the first to publish that AChEI therapy with donepezil alters lipokine levels, which positively influences the currently known pathomechanism and numerous risk factors of AD. The AChEI treatment-induced weight loss should be considered in the long-term therapy of AD patients.

  5. Cholinesterases in development: AChE as a firewall to inhibit cell proliferation and support differentiation.

    PubMed

    Layer, Paul G; Klaczinski, Janine; Salfelder, Anika; Sperling, Laura E; Thangaraj, Gopenath; Tuschl, Corina; Vogel-Höpker, Astrid

    2013-03-25

    Acetylcholinesterase (AChE) is a most remarkable protein, not only because it is one of the fastest enzymes in nature, but also since it appears in many molecular forms and is regulated by elaborate genetic networks. AChE is expressed in many tissues during development and in mature organisms, as well as in healthy and diseased states. In search for alternative, "non-classical" functions of cholinesterases (ChEs), AChE could either work within the frame of classic cholinergic systems, but in non-neural tissues ("non-synaptic function"), or act non-enzymatically. Here, we review briefly some of the major ideas and advances of this field, and report on some recent progress from our own experimental work, e.g. that (i) non-neural ChEs have pronounced, predominantly enzymatic effects on early embryonic (limb) development in chick and mouse, that (ii) retinal R28 cells of the rat overexpressing synaptic AChE present a significantly decreased cell proliferation, and that (iii) in developing chick retina ACh-synthesizing and ACh-degrading cells originate from the same postmitotic precursor cells, which later form two locally opposing cell populations. We suggest that such distinct distributions of ChAT(+) vs. AChE(+) cells in the inner half retina provide graded distributions of ACh, which can direct cell differentiation and network formation. Thus, as corroborated by works from many labs, AChE can be considered a highly co-opting protein, which can combine enzymatic and non-enzymatic functions within one molecule.

  6. Increased acetylcholine esterase activity produced by the administration of an aqueous extract of the seed kernel of Thevetia peruviana and its role on acute and subchronic intoxication in mice

    PubMed Central

    Marroquín-Segura, Rubén; Calvillo-Esparza, Ricardo; Mora-Guevara, José Luis Alfredo; Tovalín-Ahumada, José Horacio; Aguilar-Contreras, Abigail; Hernández-Abad, Vicente Jesús

    2014-01-01

    Background: The real mechanism for Thevetia peruviana poisoning remains unclear. Cholinergic activity is important for cardiac function regulation, however, the effect of T. peruviana on cholinergic activity is not well-known. Objective: To study the effect of the acute administration of an aqueous extract of the seed kernel of T. peruviana on the acetylcholine esterase (AChE) activity in CD1 mice as well its implications in the sub-chronic toxicity of the extract. Materials and Methods: A dose of 100 mg/kg of the extract was administered to CD1 mice and after 7 days, serum was obtained for ceruloplasmin (CP) quantitation and liver function tests. Another group of mice received a 50 mg/kg dose of the extract 3 times within 1 h time interval and AChE activity was determined for those animals. Heart tissue histological preparation was obtained from a group of mice that received a daily 50 mg/kg dose of the extract by a 30-days period. Results: CP levels for the treated group were higher than those for the control group (Student's t-test, P ≤ 0.001). AChE activity in the treated group was significantly higher than the control group (Tukey test, control vs. T. peruviana, P ≤ 0.001). Heart tissue histological preparations showed leukocyte infiltrates and necrotic areas, consistent with infarcts. Conclusion: The increased levels of AChE and the hearth tissue infiltrative lesions induced by the aqueous seed kernel extract of T. peruviana explains in part the poisoning caused by this plant, which can be related to an inflammatory process. PMID:24914300

  7. Anti-listeria activity of poly(lactic acid)/sawdust particle biocomposite film impregnated with pediocin PA-1/AcH and its use in raw sliced pork.

    PubMed

    Woraprayote, Weerapong; Kingcha, Yutthana; Amonphanpokin, Pannawit; Kruenate, Jittiporn; Zendo, Takeshi; Sonomoto, Kenji; Benjakul, Soottawat; Visessanguan, Wonnop

    2013-10-15

    A novel poly(lactic acid) (PLA)/sawdust particle (SP) biocomposite film with anti-listeria activity was developed by incorporation of pediocin PA-1/AcH (Ped) using diffusion coating method. Sawdust particle played an important role in embedding pediocin into the hydrophobic PLA film. The anti-listeria activity of the PLA/SP biocomposite film incorporated with Ped (PLA/SP+Ped) was detected, while no activity against the tested pathogen was observed for the control PLA films (without SP and/or Ped). Dry-heat treatment of film before coating with Ped resulted in the highest Ped adsorption (11.63 ± 3.07 μg protein/cm(2)) and the highest anti-listeria activity. A model study of PLA/SP+Ped as a food-contact antimicrobial packaging on raw sliced pork suggests a potential inhibition of Listeria monocytogenes (99% of total listerial population) on raw sliced pork during the chilled storage. This study supports the feasibility of using PLA/SP+Ped film to reduce the initial load of L. monocytogenes on the surface of raw pork.

  8. Acrylonitrile has Distinct Hormetic Effects on Acetyl-Cholinesterase Activity in Mouse Brain and Blood that are Modulated by Ethanol

    PubMed Central

    Yuanqing, He; Suhua, Wang; Guangwei, Xing; Chunlan, Ren; Hai, Qian; Wenrong, Xu; Rongzhu, Lu; Aschner, Michael; Milatovic, Dejan

    2013-01-01

    Acrylonitrile(AN) is a neurotoxin both in animals and humans, but its effects on acetylcholinesterase (AChE) activity remain controversial. This study aimed to determine the dose-response effects of AN on AChE activity and the modulatory role of ethanol pre-treatment. A total of 144 Kunming mice were randomly divided into 18 groups: nine groups received 5% ethanol in their drinking water, and the remaining nine groups received regular tap water. One week later, both the ethanol and tap water only groups were given an intraperitoneal injection of AN at the following doses: 0 (control), 0.156, 0.3125, 0.625, 1.25, 2.5, 5, 10 or 20 mg AN/kg body weight. AChE activity was determined on whole blood and brain 24 h later. Blood AChE activity was higher in AN-injected mice than in controls at all doses. AChE activity in blood increased in a dose-dependent manner, peaking at 0.156 mg/kg, after which a gradual decrease ensued, displaying a β-typed dose-response relationship. In contrast, brain AChE activity, following a single AN injection, was consistently lower than in control mice, and continued to fall up to a dose of 0.313 mg/kg, and thereafter increased gradually with higher doses. Mice receiving a 20 mg/kg dose of AN exhibited AChE brain activity indistinguishable from that of control mice, demonstrating a typical U-typed dose-response relationship. The activity of AChE in the blood and brain of the AN + ethanol-treated groups displayed a shift to the right, and the magnitude of the decrease in AChE activity induced by AN was attenuated relative to the AN-only group. These results suggest that AN affects AChE activity in both mouse blood and brain in a hormetic manner. Pretreatment with ethanol modifies the effect of AN on AChE, indicating that parent AN has a more prominent role than its metabolites in modulating enzyme activity. PMID:23550232

  9. Exergames: Increasing Physical Activity through Effective Instruction

    ERIC Educational Resources Information Center

    Rudella, Jennifer L.; Butz, Jennifer V.

    2015-01-01

    Due to the growing obesity epidemic in the United States, educators must consider new ways to increase physical activity in an effort to address obesity. There are a variety of ways educators can increase physical activity in the classroom, and exergames--video games that require physical movement in order to play--are a modern-day approach to…

  10. Synthesis, biological evaluation, and computational studies of Tri- and tetracyclic nitrogen-bridgehead compounds as potent dual-acting AChE inhibitors and hH3 receptor antagonists.

    PubMed

    Darras, Fouad H; Pockes, Steffen; Huang, Guozheng; Wehle, Sarah; Strasser, Andrea; Wittmann, Hans-Joachim; Nimczick, Martin; Sotriffer, Christoph A; Decker, Michael

    2014-03-19

    Combination of AChE inhibiting and histamine H3 receptor antagonizing properties in a single molecule might show synergistic effects to improve cognitive deficits in Alzheimer's disease, since both pharmacological actions are able to enhance cholinergic neurotransmission in the cortex. However, whereas AChE inhibitors prevent hydrolysis of acetylcholine also peripherally, histamine H3 antagonists will raise acetylcholine levels mostly in the brain due to predominant occurrence of the receptor in the central nervous system. In this work, we designed and synthesized two novel classes of tri- and tetracyclic nitrogen-bridgehead compounds acting as dual AChE inhibitors and histamine H3 antagonists by combining the nitrogen-bridgehead moiety of novel AChE inhibitors with a second N-basic fragment based on the piperidinylpropoxy pharmacophore with different spacer lengths. Intensive structure-activity relationships (SARs) with regard to both biological targets led to compound 41 which showed balanced affinities as hAChE inhibitor with IC50 = 33.9 nM, and hH3R antagonism with Ki = 76.2 nM with greater than 200-fold selectivity over the other histamine receptor subtypes. Molecular docking studies were performed to explain the potent AChE inhibition of the target compounds and molecular dynamics studies to explain high affinity at the hH3R.

  11. Synthesis, Biological Evaluation, and Computational Studies of Tri- and Tetracyclic Nitrogen-Bridgehead Compounds as Potent Dual-Acting AChE Inhibitors and hH3 Receptor Antagonists

    PubMed Central

    2014-01-01

    Combination of AChE inhibiting and histamine H3 receptor antagonizing properties in a single molecule might show synergistic effects to improve cognitive deficits in Alzheimer’s disease, since both pharmacological actions are able to enhance cholinergic neurotransmission in the cortex. However, whereas AChE inhibitors prevent hydrolysis of acetylcholine also peripherally, histamine H3 antagonists will raise acetylcholine levels mostly in the brain due to predominant occurrence of the receptor in the central nervous system. In this work, we designed and synthesized two novel classes of tri- and tetracyclic nitrogen-bridgehead compounds acting as dual AChE inhibitors and histamine H3 antagonists by combining the nitrogen-bridgehead moiety of novel AChE inhibitors with a second N-basic fragment based on the piperidinylpropoxy pharmacophore with different spacer lengths. Intensive structure–activity relationships (SARs) with regard to both biological targets led to compound 41 which showed balanced affinities as hAChE inhibitor with IC50 = 33.9 nM, and hH3R antagonism with Ki = 76.2 nM with greater than 200-fold selectivity over the other histamine receptor subtypes. Molecular docking studies were performed to explain the potent AChE inhibition of the target compounds and molecular dynamics studies to explain high affinity at the hH3R. PMID:24422467

  12. AChE Inhibition-based Multi-target-directed Ligands, a Novel Pharmacological Approach for the Symptomatic and Disease-modifying Therapy of Alzheimer's Disease

    PubMed Central

    Wang, Yu; Wang, Hao; Chen, Hong-zhuan

    2016-01-01

    Alzheimer's disease (AD) is the most common form of dementia in elder people, characterised by a progressive decline in memory as a result of an impairment of cholinergic neurotransmission. To date acetylcholinesterase inhibitors (AChEIs) have become the most prescribed drugs for the symptomatic treatment of mild to moderate AD. However, the traditional “one molecule-one target” paradigm is not sufficient and appropriate to yield the desired therapeutic efficacy since multiple factors, such as amyloid-β (Aβ) deposits, neuroinflammation, oxidative stress, and decreased levels of acetylcholine (ACh) have been thought to play significant roles in the AD pathogenesis. New generation of multi-target drugs is earnestly demanded not only for ameliorating symptoms but also for modifying the disease. Herein, we delineated the catalytic and non-catalytic functions of AChE, and summarized the works of our group and others in research and development of novel AChEI-based multi-target-directed ligands (MTDLs), such as dual binding site AChEIs and multi-target AChEIs inhibiting Aβ aggregation, regulating Aβ procession, antagonizing platelet-activating factor (PAF) receptor, scavenging oxygen radical, chelating metal ions, inhibiting monoamine oxidase B (MAO-B), blocking N-methyl-D-aspartic acid (NMDA) receptor and others. PMID:26786145

  13. Gentamicin Blocks the ACh-Induced BK Current in Guinea Pig Type II Vestibular Hair Cells by Competing with Ca2+ at the l-Type Calcium Channel

    PubMed Central

    Yu, Hong; Guo, Chang-Kai; Wang, Yi; Zhou, Tao; Kong, Wei-Jia

    2014-01-01

    Type II vestibular hair cells (VHCs II) contain big-conductance Ca2+-dependent K+ channels (BK) and l-type calcium channels. Our previous studies in guinea pig VHCs II indicated that acetylcholine (ACh) evoked the BK current by triggering the influx of Ca2+ ions through l-type Ca2+ channels, which was mediated by M2 muscarinic ACh receptor (mAChRs). Aminoglycoside antibiotics, such as gentamicin (GM), are known to have vestibulotoxicity, including damaging effects on the efferent nerve endings on VHCs II. This study used the whole-cell patch clamp technique to determine whether GM affects the vestibular efferent system at postsynaptic M2-mAChRs or the membrane ion channels. We found that GM could block the ACh-induced BK current and that inhibition was reversible, voltage-independent, and dose-dependent with an IC50 value of 36.3 ± 7.8 μM. Increasing the ACh concentration had little influence on GM blocking effect, but increasing the extracellular Ca2+ concentration ([Ca2+]o) could antagonize it. Moreover, 50 μM GM potently blocked Ca2+ currents activated by (−)-Bay-K8644, but did not block BK currents induced by NS1619. These observations indicate that GM most likely blocks the M2 mAChR-mediated response by competing with Ca2+ at the l-type calcium channel. These results provide insights into the vestibulotoxicity of aminoglycoside antibiotics on mammalian VHCs II. PMID:24758923

  14. Synthesis and biological activity of a novel class nicotinic acetylcholine receptors (nAChRs) ligands structurally related to anatoxin-a.

    PubMed

    Simoni, Daniele; Rondanin, Riccardo; Marchetti, Paolo; Rullo, Cinzia; Baruchello, Riccardo; Grisolia, Giuseppina; Barbato, Giuseppina; Giovannini, Riccardo; Marchioro, Carla; Capelli, Anna Maria; Virginio, Caterina; Bozzoli, Andrea; Borea, Pier Andrea; Merighi, Stefania; Donati, Daniele

    2011-09-15

    The introduction of the isoxazole ring as bioisosteric replacement of the acetyl group of anatoxin-a led to a new series of derivatives binding to nicotinic acetylcholine receptors. Bulkier substitutions than methyl at the 3 position of isoxazole were shown to be detrimental for the activity. The binding potency of the most interesting compounds with α1, α7 and α3β4 receptor subtypes, was, anyway, only at micromolar level. Moreover, differently from known derivatives with pyridine, isoxazole condensed to azabicyclo ring led to no activity.

  15. Immune responses to HTLV-I(ACH) during acute infection of pig-tailed macaques.

    PubMed

    McGinn, Therese M; Wei, Qing; Stallworth, Jackie; Fultz, Patricia N

    2004-04-01

    Human T cell lymphotropic virus type 1 (HTLV-I) is causally linked to adult T cell leukemia/lymphoma (ATL) and a chronic progressive neurological disease, HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP). A nonhuman primate model that reproduces disease symptoms seen in HTLV-I-infected humans might facilitate identification of initial immune responses to the virus and an understanding of pathogenic mechanisms in HTLV-I-related disease. Previously, we showed that infection of pig-tailed macaques with HTLV-I(ACH) is associated with multiple signs of disease characteristic of both HAM/TSP and ATL. We report here that within the first few weeks after HTLV-I(ACH) infection of pig-tailed macaques, serum concentrations of interferon (IFN)-alpha increased and interleukin-12 decreased transiently, levels of nitric oxide were elevated, and activation of CD4(+) and CD8(+) lymphocytes and CD16(+) natural killer cells in peripheral blood were observed. HTLV-I(ACH) infection elicited virus-specific antibodies in all four animals within 4 to 6 weeks; however, Tax-specific lymphoproliferative responses were not detected until 25-29 weeks after infection in all four macaques. IFN-gamma production by peripheral blood cells stimulated with a Tax or Gag peptide was detected to varying degrees in all four animals by ELISPOT assay. Peripheral blood lymphocytes from one animal that developed only a marginal antigen-specific cellular response were unresponsive to mitogen stimulation during the last few weeks preceding its death from a rapidly progressive disease syndrome associated with HTLV-I(ACH) infection of pig-tailed macaques. The results show that during the first few months after HTLV-I(ACH) infection, activation of both innate and adaptive immunity, limited virus-specific cellular responses, sustained immune system activation, and, in some cases, immunodeficiency were evident. Thus, this animal model might be valuable for understanding early stages of infection

  16. Effects of systemically applied nAChRα7 agonists and antagonists on light-induced phase shifts of hamster circadian activity rhythms.

    PubMed

    Gannon, Robert L; Garcia, David A; Millan, Mark J

    2014-06-01

    Many physiological systems in mammals are linked to the body's master circadian rhythm in the sleep/wake cycle and dysfunctions in this rhythm has been associated with neurological diseases such as major depression, Alzheimer's Disease and schizophrenia. There is some evidence that nicotinic cholinergic input to the master circadian pacemaker, the suprachiasmatic nucleus, may modulate circadian activity rhythms, but data employing in vivo preparations is sparse. Therefore we examined the ability of intraperitoneally applied nicotinic agonists and antagonists relatively selective for the α7 nicotinic receptor to modulate light-induced phase shifts of hamster circadian wheel running rhythms. Hamsters were maintained in constant darkness and exposed to light pulses early and late in their active period, mimicking dusk and dawn respectively, which elicited phase delays and advances of their circadian wheel running rhythms. The α7 receptor antagonists bPiDDB (0.03-3mg/kg) and methyllacaconitine (0.1-1mg/kg) inhibited both light- induced phase advances and delays of circadian wheel running rhythms by as much as 75% versus vehicle injections. In contrast, systemic injections of the α7 agonists PHA 543613 and ABT107, both at 0.156-2.5mg/kg, had no effect on light induced phase advances or delays. Further, α7 nicotinic receptors were identified in the hamster suprachiasmatic nucleus using an antibody that recognizes α7 nicotinic receptors. These results clearly identify the ability of α7 nicotinic receptor antagonists to inhibit light-entrainment of the hamster circadian pacemaker. Therefore, nicotinic compounds may be useful for the treatment of circadian dysfunction associated with neurological diseases.

  17. Analysis of free ACh and 5-HT in milk from four different species and their bioactivity on 5-HT(3) and nACh receptors.

    PubMed

    Gallegos-Perez, Jose-Luis; Limon, Agenor; Reyes-Ruiz, Jorge M; Alshanqeeti, Ali S; Aljohi, Mohammad A; Miledi, Ricardo

    2014-07-25

    Milk is one of the most beneficial aliments and is highly recommended in normal conditions; however, in certain disorders, like irritable bowel syndrome, cow milk and dairy products worsen the gastric symptoms and their use is not recommended. Among the most recognized milk-induced gatrointestinal symptoms are abdominal pain, nausea and vomiting, which are processes controlled by cholinergic and serotonergic transmission. Whether the presence of bioavailable ACh and 5-HT in milk may contribute to normal peristalsis, or to the developing of these symptoms, is not known. In this work we attempt to determine whether the content of free ACh and 5-HT is of physiological significance in milk from four different species: cow (bovine), goat, camel and human. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used to identify and quantify free ACh and 5-HT in milk, and activation of the serotonergic and cholinergic ionotropic receptors was investigated using electrophysiological experiments. Our principal hypothesis was that milk from these four species had sufficient free ACh and 5-HT to activate their correspondent receptors expressed in a heterologous system. Our results showed a more complex picture, in which free ACh and 5-HT and their ability to activate cholinergic and serotonergic receptors are not correlated. This work is a first step to elucidate whether 5-HT and ACh, at the concentrations present in the milk, can be associated to a direct function in the GI.

  18. Discovery of Highly Potent and Selective α4β2-Nicotinic Acetylcholine Receptor (nAChR) Partial Agonists Containing an Isoxazolylpyridine Ether Scaffold that Demonstrate Antidepressant-like Activity. Part II

    PubMed Central

    Yu, Li-Fang; Eaton, J. Brek; Fedolak, Allison; Zhang, Han-Kun; Hanania, Taleen; Brunner, Dani; Lukas, Ronald J.; Kozikowski, Alan P.

    2012-01-01

    In our continued efforts to develop α4β2-nicotinic acetylcholine receptor (nAChR) partial agonists as novel antidepressants having a unique mechanism of action, structure activity relationship (SAR) exploration of certain isoxazolylpyridine ethers is presented. In particular, modifications to both the azetidine ring present in the starting structure 4 and its metabolically liable hydroxyl side chain substituent have been explored to improve compound druggability. The pharmacological characterization of all new compounds has been carried out using [3H]epibatidine binding studies together with functional assays based on 86Rb+ ion flux measurements. We found that the deletion of the metabolically liable hydroxyl group or its replacement by a fluoromethyl group not only maintained potency and selectivity, but also resulted in compounds showing antidepressant-like properties in the mouse forced swim test. These isoxazolylpyridine ethers appear to represent promising lead candidates in the design of innovative chemical tools containing reporter groups for imaging purposes and of possible therapeutics. PMID:23092294

  19. Discovery of highly potent and selective α4β2-nicotinic acetylcholine receptor (nAChR) partial agonists containing an isoxazolylpyridine ether scaffold that demonstrate antidepressant-like activity. Part II.

    PubMed

    Yu, Li-Fang; Eaton, J Brek; Fedolak, Allison; Zhang, Han-Kun; Hanania, Taleen; Brunner, Dani; Lukas, Ronald J; Kozikowski, Alan P

    2012-11-26

    In our continued efforts to develop α4β2-nicotinic acetylcholine receptor (nAChR) partial agonists as novel antidepressants having a unique mechanism of action, structure-activity relationship (SAR) exploration of certain isoxazolylpyridine ethers is presented. In particular, modifications to both the azetidine ring present in the starting structure 4 and its metabolically liable hydroxyl side chain substituent have been explored to improve compound druggability. The pharmacological characterization of all new compounds has been carried out using [(3)H]epibatidine binding studies together with functional assays based on (86)Rb(+) ion flux measurements. We found that the deletion of the metabolically liable hydroxyl group or its replacement by a fluoromethyl group not only maintained potency and selectivity but also resulted in compounds showing antidepressant-like properties in the mouse forced swim test. These isoxazolylpyridine ethers appear to represent promising lead candidates in the design of innovative chemical tools containing reporter groups for imaging purposes and of possible therapeutics.

  20. Repetitive obidoxime treatment induced increase of red blood cell acetylcholinesterase activity even in a late phase of a severe methamidophos poisoning: A case report.

    PubMed

    Steinritz, Dirk; Eyer, Florian; Worek, Franz; Thiermann, Horst; John, Harald

    2016-02-26

    Accidental self-poisoning or deliberate use in suicidal intent of organophosphorus pesticides (OPP), which are widely used in agriculture, represent a health problem worldwide. Symptoms of poisoning are characterized by acute cholinergic crisis caused by inhibition of acetylcholinesterase. A 75-year-old male patient ingested 20ml of an OPP solution containing 10% methamidophos in suicidal intent. In the course of poisoning typical clinical symptoms of cholinergic crisis (miosis, bradycardia, hypotension, hypersalivation and impairment of neurologic status) were evident. Butyryl (plasma) cholinesterase (BChE) and red blood cell acetylcholinesterase (RBC-AChE) revealed decreased activities, thus specific treatment with the enzyme reactivator obidoxime was started. Inhibitory activity of the patient's plasma indicated significant amounts of persisting methamidophos in the circulation and was still found on day 4 after ingestion. Due to missing spontaneous breathing on day 6, obidoxime was administered again. Afterwards a significant increase of RBC-AChE activity was found. The patient was extubated on day 10 and a restitution ad integrum was achieved. In conclusion, obidoxime is a potent reactivator of OPP-inhibited AChE. A repetitive and prolonged administration of obidoxime should be considered in cases of severe methamidophos poisoning and should be tailored with an advanced analytical biomonitoring.

  1. n/Ach Among Agricultural and Business Entrepreneurs of Delhi

    ERIC Educational Resources Information Center

    Singh, Narayan Prasad

    1970-01-01

    Given the wide acceptance of n/Ach in current research as a critical non-economic variable affecting entrepreneurship, the present study tests Atkinson's hypothesis of n/Ach--that individuals with high n/Ach are more susceptible to changes in economic opportunities than their counterparts with low n/Ach. (SE)

  2. Increased Ribozyme Activity in Crowded Solutions*

    PubMed Central

    Desai, Ravi; Kilburn, Duncan; Lee, Hui-Ting; Woodson, Sarah A.

    2014-01-01

    Noncoding RNAs must function in the crowded environment of the cell. Previous small-angle x-ray scattering experiments showed that molecular crowders stabilize the structure of the Azoarcus group I ribozyme, allowing the ribozyme to fold at low physiological Mg2+ concentrations. Here, we used an RNA cleavage assay to show that the PEG and Ficoll crowder molecules increased the biochemical activity of the ribozyme, whereas sucrose did not. Crowding lowered the Mg2+ threshold at which activity was detected and increased total RNA cleavage at high Mg2+ concentrations sufficient to fold the RNA in crowded or dilute solution. After correcting for solution viscosity, the observed reaction rate was proportional to the fraction of active ribozyme. We conclude that molecular crowders stabilize the native ribozyme and favor the active structure relative to compact inactive folding intermediates. PMID:24337582

  3. Electronic structure calculations toward new potentially AChE inhibitors

    NASA Astrophysics Data System (ADS)

    de Paula, A. A. N.; Martins, J. B. L.; Gargano, R.; dos Santos, M. L.; Romeiro, L. A. S.

    2007-10-01

    The main purpose of this study was the use of natural non-isoprenoid phenolic lipid of cashew nut shell liquid from Anacardium occidentale as lead material for generating new potentially candidates of acetylcholinesterase inhibitors. Therefore, we studied the electronic structure of 15 molecules derivatives from the cardanol using the following groups: methyl, acetyl, N, N-dimethylcarbamoyl, N, N-dimethylamine, N, N-diethylamine, piperidine, pyrrolidine, and N-benzylamine. The calculations were performed at RHF level using 6-31G, 6-31G(d), 6-31+G(d) and 6-311G(d,p) basis functions. Among the proposed compounds we found that the structures with substitution by acetyl, N, N-dimethylcarbamoyl, N, N-dimethylamine, and pyrrolidine groups were better correlated to rivastigmine indicating possible activity.

  4. Exploration of the susceptibility of AChE from the poultry red mite Dermanyssus gallinae (Acari: Mesostigmata) to organophosphates in field isolates from France.

    PubMed

    Roy, Lise; Chauve, Claude; Delaporte, Jean; Inizan, Gilbert; Buronfosse, Thierry

    2009-06-01

    The red fowl mite Dermanyssus gallinae (De Geer, 1778) is a hematophagous mite species, which is very commonly found in layer facilities in Europe. The economic and animal health impact of this parasite is quite important. In laying hen houses, organophosphates are almost the only legally usable chemicals. Detecting a target resistance can be useful in order to limit the emergence of resistant populations. The acetylcholinesterase (AChE) activity and the enzyme sensitivity to paraoxon was investigated in 39 field samples and compared to a susceptible reference strain (SSK). Insensitivity factor values (expressed as IC50 ratio) obtained from field isolates compared to SSK revealed some polymorphism but not exceeding a 6-fold difference. The kinetic characteristics of AChE from some field samples showed some difference in KM values for acetylthiocholine and inhibition kinetics performed with diethyl paraoxon exhibited a 5.5-fold difference in the bimolecular rate constant in one field isolate. Taken together, these data suggested that differences in AChE susceptibility to organophosphates may exist in D. gallinae but no resistant population was found.

  5. Design of multi-target compounds as AChE, BACE1, and amyloid-β(1-42) oligomerization inhibitors: in silico and in vitro studies.

    PubMed

    Hernández-Rodríguez, Maricarmen; Correa-Basurto, José; Martínez-Ramos, Federico; Padilla-Martínez, Itzia Irene; Benítez-Cardoza, Claudia G; Mera-Jiménez, Elvia; Rosales-Hernández, Martha Cecilia

    2014-01-01

    Despite great efforts to develop new therapeutic strategies against Alzheimer's disease (AD), the acetylcholinesterase inhibitors (AChEIs): donepezil, rivastigmine, and galantamine, have been used only as a palliative therapeutic approach. However, the pathogenesis of AD includes several factors such as cholinergic hypothesis, amyloid-β (Aβ) aggregation, and oxidative stress. For this reason, the design of compounds that target the genesis and progression of AD could offer a therapeutic benefit. We have designed a set of compounds (M-1 to M-5) with pharmacophore moieties to inhibit the release, aggregation, or toxicity of Aβ, act as AChEIs and have antioxidant properties. Once the compounds were designed, we analyzed their physicochemical parameters and performed docking studies to determine their affinity values for AChE, β-site amyloid-protein precursor cleaving enzyme 1 (BACE1), and the Aβ monomer. The best ligands, M-1 and M-4, were then synthesized, chemically characterized, and evaluated in vitro. The in vitro studies showed that these compounds inhibit AChE (M-1 Ki = 0.12 and M-4 Ki = 0.17 μM) and BACE1 (M-1 IC50 = 15.1 and M-4 IC50 = 15.4 nM). They also inhibit Aβ oligomerization and exhibit antioxidant activity. In addition, these compounds showed low cytotoxicity in microglial cells. For these reasons, they are promising for future use as drugs in AD mice transgenic models.

  6. Modulation of recombinant, α2*, α3* or α4*-nicotinic acetylcholine receptor (nAChR) function by nAChR β3 subunits.

    PubMed

    Dash, Bhagirathi; Bhakta, Minoti; Chang, Yongchang; Lukas, Ronald J

    2012-05-01

    The nicotinic acetylcholine receptor (nAChR) β3 subunit is thought to serve an accessory role in nAChR subtypes expressed in dopaminergic regions implicated in drug dependence and reward. When β3 subunits are expressed in excess, they have a dominant-negative effect on function of selected nAChR subtypes. In this study, we show, in Xenopus oocytes expressing α2, α3 or α4 plus either β2 or β4 subunits, that in the presumed presence of similar amounts of each nAChR subunit, co-expression with wild-type β3 subunits generally (except for α3*-nAChR) lowers amplitudes of agonist-evoked, inward peak currents by 20-50% without having dramatic effects (≤ 2-fold) on agonist potencies. By contrast, co-expression with mutant β3(V9'S) subunits generally (except for α4β2*-nAChR) increases agonist potencies, consistent with an expected gain-of-function effect. This most dramatically demonstrates formation of complexes containing three kinds of subunit. Moreover, for oocytes expressing nAChR containing any α subunit plus β4 and β3(V9'S) subunits, there is spontaneous channel opening sensitive to blockade by the open channel blocker, atropine. Collectively, the results indicate that β3 subunits integrate into all of the studied receptor assemblies and suggest that natural co-expression with β3 subunits can influence levels of expression and agonist sensitivities of several nAChR subtypes.

  7. Ni nanoparticle catalyzed growth of MWCNTs on Cu NPs @ a-C:H substrate

    NASA Astrophysics Data System (ADS)

    Ghodselahi, T.; Solaymani, S.; Akbarzadeh Pasha, M.; Vesaghi, M. A.

    2012-11-01

    NiCu NPs @ a-C:H thin films with different Cu content were prepared by co-deposition by RF-sputtering and RF-plasma enhanced chemical vapor deposition (RF-PECVD) from acetylene gas and Cu and Ni targets. The prepared samples were used as catalysts for growing multi-wall carbon nanotubes (MWCNTs) from liquid petroleum gas (LPG) at 825 °C by thermal chemical vapor deposition (TCVD). By addition of Cu NPs @ a-C:H thin layer as substrate for Ni NPs catalyst, the density of the grown CNTs is greatly enhanced in comparison to bare Si substrate. Furthermore the average diameter of the grown CNTs decreases by decreasing of Cu content of Cu NPs @ a-C:H thin layer. However Cu NPs @ a-C:H by itself has no catalytic property in MWCNTs growth. Morphology and electrical and optical properties of Cu NPs @ a-C:H thin layer is affected by Cu content and each of them is effective parameter on growth of MWCNTs based on Ni NPs catalyst. Moreover, adding of a low amount of Ni NPs doesn't vary optical, electrical and morphology properties of Cu NPs @ a-C:H thin layer but it has a profound effect on its catalytic activity. Finally the density and diameter of MWCNTs can be optimized by selection of the Cu NPs @ a-C:H thin layer as substrate of Ni NPs.

  8. Neurokinin2-R in medial septum regulate hippocampal and amygdalar ACh release induced by intraseptal application of neurokinins A and B.

    PubMed

    Schäble, Sandra; Huston, Joseph P; Silva, Maria A de Souza

    2012-05-01

    The neurokinin receptors (NK-R), NK(2)- and NK(3)-R, have been implicated in behavioral processes, but apparently in opposite ways: while NK(2)-R agonism disrupts memory and has anxiogenic-like action, NK(3) -R agonists facilitate memory and display anxiolytic-like effects. Systemic application of NK(2)-R antagonists block the release of acetylcholine (ACh) in the hippocampus, which is induced by intraseptal administration of the NK(2)-R ligand, neurokinin A (NKA). We investigated the effects of medial septal injection of NKA and a preferred ligand of NK(3)-R, neurokinin B (NKB), on the activity of cholinergic neurons of the basal forebrain and assessed the role of the medial septal NK(2)-R in the control of extracellular ACh levels in cholinergic projection areas. ACh was dialysed in the frontal cortex, amygdala and hippocampus of anesthetized animals and was analysed by HPLC-EC. ACh levels in hippocampus and amygdala, but not in frontal cortex were increased after intraseptal injection of either NKA or NKB (0.1, 1, 10 μM). Application of the nonpeptidic NK(2)-R antagonist, saredutant SR48968 (1, 10, 100 pM), followed by NKA (1 μM) or NKB (10 μM) injection into the medial septum, blocked the ACh increase in hippocampus and amygdala. These results indicate that medial septal NK(2)-R have an important role in mediating ACh release, for one, via the septal-hippocampal cholinergic projection and, secondly, via direct or indirect route to the amygdala, but not frontal cortex. They also support the hypothesis that hippocampal cholinergic neurotransmission controls amygdala function suggesting that this interaction is regulated via NK(2)-R in the medial septum.

  9. Folic acid supplementation increases cutaneous vasodilator sensitivity to sympathetic nerve activity in older adults.

    PubMed

    Stanhewicz, Anna E; Greaney, Jody L; Alexander, Lacy M; Kenney, W Larry

    2017-02-22

    During heat stress, blunted increases in skin sympathetic nervous system activity (SSNA) and reductions in end-organ vascular responsiveness contribute to the age-related reduction in reflex cutaneous vasodilation. In older adults, folic acid supplementation improves the cutaneous vascular conductance (CVC) response to passive heating; however, the influence of folic acid supplementation on SSNA:CVC transduction is unknown. Fourteen older adults (66±1yrs, 8M/6F) ingested folic acid (5mg·day(-1)) or placebo for 6 weeks in a randomized, double-blind, crossover design. In protocol 1, esophageal temperature (Tes) was increased by 1.0ºC (water-perfused suit) while SSNA (peroneal microneurography) and red cell flux in the innervated dermatome (laser Doppler flowmetry; dorsum of the foot) were continuously measured. In protocol 2, two intradermal microdialysis fibers were placed in the skin of the lateral calf for graded infusions of acetylcholine (ACh; 10(-10) to 10(-1)M) with and without nitric oxide synthase (NOS) blockade (20mM L-NAME). Folic acid improved reflex vasodilation (46±4% vs. 31±3 %CVCmax for placebo; P<0.001) without affecting the increase in SSNA (Δ506±104% vs. Δ415±73% for placebo; NS). Folic acid increased the slope of the SSNA:CVC relation (0.08±0.02 vs. 0.05±0.01 for placebo; P<0.05) and extended the response range. Folic acid augmented ACh-induced vasodilation (83±3% vs. 66±4 %CVCmax for placebo; P=0.002); however there was no difference between treatments at the NOS-inhibited site (53±4% vs. 52±4% CVCmax for placebo; NS). These data demonstrate that folic acid supplementation enhances reflex vasodilation by increasing the sensitivity of skin arterioles to central sympathetic nerve outflow during hyperthermia in aged human subjects.

  10. Generation of Recombinant Human AChE OP-Scavengers with Extended Circulatory Longevity

    DTIC Science & Technology

    2006-11-01

    glaucoma or myasthenia gravis (Taylor, 1990). Some organophosphorus (OP) inhibitors of ChEs such as malathion and diazinon, act as efficient...2000); site directed mutagenesis and molecular modeling together with kinetic studies of the 7 AChE muteins with substrates and reversible...of the individual lysine residues does not alter the kinetic performance of the enzyme. Based solely on this criterion, any of the lysine residues

  11. Artemin growth factor increases nicotinic cholinergic receptor subunit expression and activity in nociceptive sensory neurons

    PubMed Central

    2014-01-01

    Background Artemin (Artn), a member of the glial cell line-derived growth factor (GDNF) family, supports the development and function of a subpopulation of peptidergic, TRPV1-positive sensory neurons. Artn (enovin, neublastin) is elevated in inflamed tissue and its injection in skin causes transient thermal hyperalgesia. A genome wide expression analysis of trigeminal ganglia of mice that overexpress Artn in the skin (ART-OE mice) showed elevation in nicotinic acetylcholine receptor (nAChR) subunits, suggesting these ion channels contribute to Artn-induced sensitivity. Here we have used gene expression, immunolabeling, patch clamp electrophysiology and behavioral testing assays to investigate the link between Artn, nicotinic subunit expression and thermal hypersensitivity. Results Reverse transcriptase-PCR validation showed increased levels of mRNAs encoding the nAChR subunits α3 (13.3-fold), β3 (4-fold) and β4 (7.7-fold) in trigeminal ganglia and α3 (4-fold) and β4 (2.8-fold) in dorsal root ganglia (DRG) of ART-OE mice. Sensory ganglia of ART-OE mice had increased immunoreactivity for nAChRα3 and exhibited increased overlap in labeling with GFRα3-positive neurons. Patch clamp analysis of back-labeled cutaneous afferents showed that while the majority of nicotine-evoked currents in DRG neurons had biophysical and pharmacological properties of α7-subunit containing nAChRs, the Artn-induced increase in α3 and β4 subunits resulted in functional channels. Behavioral analysis of ART-OE and wildtype mice showed that Artn-induced thermal hyperalgesia can be blocked by mecamylamine or hexamethonium. Complete Freund’s adjuvant (CFA) inflammation of paw skin, which causes an increase in Artn in the skin, also increased the level of nAChR mRNAs in DRG. Finally, the increase in nAChRs transcription was not dependent on the Artn-induced increase in TRPV1 or TRPA1 in ART-OE mice since nAChRs were elevated in ganglia of TRPV1/TRPA1 double knockout mice. Conclusions

  12. Enhanced synthesis and release of dopamine in transgenic mice with gain-of-function α6* nAChRs.

    PubMed

    Wang, Yuexiang; Lee, Jang-Won; Oh, Gyeon; Grady, Sharon R; McIntosh, J Michael; Brunzell, Darlene H; Cannon, Jason R; Drenan, Ryan M

    2014-04-01

    α6β2* nicotinic acetylcholine receptors (nAChRs)s in the ventral tegmental area to nucleus accumbens (NAc) pathway are implicated in the response to nicotine, and recent work suggests these receptors play a role in the rewarding action of ethanol. Here, we studied mice expressing gain-of-function α6β2* nAChRs (α6L9'S mice) that are hypersensitive to nicotine and endogenous acetylcholine. Evoked extracellular dopamine (DA) levels were enhanced in α6L9'S NAc slices compared to control, non-transgenic (non-Tg) slices. Extracellular DA levels in both non-Tg and α6L9'S slices were further enhanced in the presence of GBR12909, suggesting intact DA transporter function in both mouse strains. Ongoing α6β2* nAChR activation by acetylcholine plays a role in enhancing DA levels, as α-conotoxin MII completely abolished evoked DA release in α6L9'S slices and decreased spontaneous DA release from striatal synaptosomes. In HPLC experiments, α6L9'S NAc tissue contained significantly more DA, 3,4-dihydroxyphenylacetic acid, and homovanillic acid compared to non-Tg NAc tissue. Serotonin (5-HT), 5-hydroxyindoleacetic acid, and norepinephrine (NE) were unchanged in α6L9'S compared to non-Tg tissue. Western blot analysis revealed increased tyrosine hydroxylase expression in α6L9'S NAc. Overall, these results show that enhanced α6β2* nAChR activity in NAc can stimulate DA production and lead to increased extracellular DA levels.

  13. Different pharmacology of N-desmethylclozapine at human and rat M2 and M 4 mAChRs in neocortex.

    PubMed

    Gigout, S; Wierschke, S; Dehnicke, C; Deisz, R A

    2015-05-01

    Cholinergic transmission plays a pivotal role in learning, memory and cognition, and disturbances of cholinergic transmission have been implicated in neurological disorders including Alzheimer's disease, epilepsy and schizophrenia. Pharmacological alleviation of these diseases by drugs including N-desmethylclozapine (NDMC), promising in animal models, often fails in patients. We therefore compared the effects of NDMC on glutamatergic and GABAergic transmission in slices from rat and human neocortex. We used carbachol (CCh; an established agonist at metabotropic muscarinic acetylcholine (ACh) receptors (mAChRs)) as a reference. Standard electrophysiological methods including intracellular and field potential recordings were used. In the rat neocortex, NDMC prevented the CCh-induced decrease of GABAA and GABAB receptor-mediated responses but not the CCh-induced increase of the paired-pulse depression. NDMC reduced neither the amplitude of the excitatory postsynaptic potentials (EPSP) nor antagonized the CCh-induced depression of EPSP. In the human neocortex, however, NDMC failed to prevent CCh-induced decrease of the GABAB responses and directly reduced the amplitude of EPSP. These data suggest distinct effects of NDMC in rat and human at M2 and M4 mAChRs underlying presynaptic modulation of GABA and glutamate release, respectively. In particular, NDMC might be a M2 mAChR antagonist in the rat but has no activity at this receptor in human neocortex. However, NDMC has an agonistic effect at M4 mAChR in the human but no such effect in the rat neocortex. The present study confirms that pharmacology at mAChRs can differ between species and emphasizes the need of studies in human tissue.

  14. Contributions of β2 subunit-containing nAChRs to chronic nicotine-induced alterations in cognitive flexibility in mice

    PubMed Central

    Cole, Robert D.; Poole, Rachel L.; Guzman, Dawn M.; Gould, Thomas J.; Parikh, Vinay

    2014-01-01

    Rationale Deficits in executive functions underlie compulsive drug use and understanding how nicotine influences these cognitive processes may provide important information on neurobiological substrates of nicotine addiction. Accumulating evidence suggests that β2 subunit-containing nicotinic receptors (nAChRs) are involved in the reinforcing process of nicotine addiction. Whether these nAChRs also contributes to the detrimental effects of chronic nicotine on flexible decision-making is not known. Objectives In the present study, the effects of chronic nicotine were assessed in mice with partial or complete deletion of the β2-subunit containing nAChR gene (β2+/- or β2-/-) performing an operant cognitive flexibility task. Results Visual discrimination learning was not affected in saline-treated β2 nAChR mutants as compared to the wild-type (β2+/+) mice; yet, chronic nicotine facilitated acquisition of visual discrimination in all genotypes. The acquisition of new egocentric response strategy set-shifting remained similar in all genotypes and there was no effect of treatment. Chronic nicotine treatment impaired reversal learning in β2+/+ mice by increasing response perseveration to the previously rewarded stimulus. Moreover, the acquisition of inverted stimulus-reward contingencies did not differ between β2+/+ and β2-/- mice exposed to chronic nicotine. Interestingly, nicotine-induced reversal learning deficits were not observed in β2+/- mice. Conclusions Collectively, these findings suggest that β2 subunit-containing nAChRs are not critical for visual discrimination learning and extradimensional rule shift. However, sustained activation of these nAChRs with nicotine may interfere with inhibitory control processes influencing affective shifts in stimulus-reward contingencies. PMID:25281224

  15. America under attack: ACHE affiliates respond.

    PubMed

    Lanser, Ellen G

    2002-01-01

    In the midst of the horror and uncertainty that swept over America on September 11, the healthcare sector helped to keep our nation firmly anchored. Within moments of the terrorist attacks, healthcare organizations in New York, Washington, D.C., and the surrounding areas responded swiftly, calmly, and effectively. Many of these hospitals are led by ACHE affiliates. Following are their accounts of that day, lessons they learned, and plans for the future.

  16. Chronic treatment with varenicline changes expression of four nAChR binding sites in mice

    PubMed Central

    Marks, Michael J.; O’Neill, Heidi C.; Wynalda-Camozzi, Kelly M.; Ortiz, Nick C.; Simmons, Emily E.; Short, Caitlin A.; Butt, Christopher M.; McIntosh, J. Michael; Grady, Sharon R.

    2015-01-01

    Introduction Chronic treatment with nicotine is known to increase the α4β2-nAChR sites in brain, to decrease α6β2-nAChR sites and to have minimal effect on α3β4- and α7-nAChR populations. Varenicline is now used as a smoking cessation treatment, with and without continued smoking or nicotine replacement therapy. Varenicline, like nicotine, upregulates the α4β2-nAChR sites; however, it is not known whether varenicline treatment changes expression of the other nAChR subtypes. Methods Using a mouse model, chronic treatments (10 days) with varenicline (0.12mg/kg/hr) and/or nicotine (1 mg/kg/hr), alone or in combination, were compared for plasma and brain levels of drugs, tolerance to subsequent acute nicotine and expression of four subtypes of nAChR using autoradiography. Results The upregulation of α4β2-nAChR sites elicited by chronic varenicline was very similar to that elicited by chronic nicotine. Treatment with both drugs somewhat increased up-regulation, indicating that these doses were not quite at maximum effect. Similar down-regulation was seen for α6β2-nAChR sites. Varenicline significantly increased both α3β4- and α7-nAChR sites while nicotine had less effect on these sites. The drug combination was similar to varenicline alone for α3β4-nAChR sites, while for α7 sites the drug combination was less effective than varenicline alone. Varenicline had small but significant effects on tolerance to acute nicotine. Conclusions Effects of varenicline in vivo may not be limited to the α4β2*-nAChR subtype. In addition, smoking cessation treatment with varenicline may not allow receptor numbers to be restored to baseline and may, in addition, change expression of other receptor subtypes. PMID:26192545

  17. Brain acetycholinesterase activity in botulism-intoxicated mallards

    USGS Publications Warehouse

    Rocke, T.E.; Samuel, M.D.

    1991-01-01

    Brain acetylcholinesterase (AChE) activity in captive-reared mallards (Anas platyrhynchos) that died of botulism was compared with euthanized controls. AChE levels for both groups were within the range reported for normal mallards, and there was no significant difference in mean AChE activity between birds that ingested botulism toxin and died and those that did not.

  18. Combined administration of anisodamine and neostigmine rescued acute lethal crush syndrome through α7nAChR-dependent JAK2-STAT3 signaling

    PubMed Central

    Xu, Zhe-Qi; Shao, Bo-Zong; Ke, Ping; Liu, Jian-Guo; Liu, Guo-Ku; Chen, Xiong-Wen; Su, Ding-Feng; Liu, Chong

    2016-01-01

    Previously we showed that Ani (anisodamine)/Neo (neostigmine) combination produced anti-shock effect via activating α7 nicotinic acetylcholine receptor (α7nAChR). In this study, we aim to investigate the therapeutic effect and underlying mechanisms of Ani/Neo combination in acute lethal crush syndrome (CS). In rat and rabbit CS models, Ani/Neo combination increased the 24 h survival rates, improved hemodynamics and decreased the levels of creatine kinase, MB isoenzyme of creatine kinase, blood urea nitrogen, creatinine, K+ in serum. It also decreased the levels of H2O2, myeloperoxidase (MPO) and nitric oxide (NO) in serum and compressed muscle in rat CS model. In wild-type (WT) mice with CS, Ani/Neo combination increased 24 h survival rate and decreased the levels of H2O2, MPO, NO, TNFα, IL-6 and IL-10 in compressed muscle. These effects were attenuated by α7nAChR knockout (KO). Moreover, Ani/Neo combination prevented the decrease of phosphorylation of Janus kinase 2 (JAK2) and phosphorylation of signal transducer and activator of transcription 3 (STAT3) induced by CS. These effects of Ani/Neo in CS mice were cancelled by methyllycaconitine (α7nAChR antagonist) and α7nAChR KO. Collectively, our results demonstrate that Ani/Neo combination could produce therapeutic effects in CS. The underlying mechanism involves the activation of α7nAChR-dependent JAK2-STAT3 signaling pathway. PMID:27874086

  19. Demonstration of Increased Permeability as a Factor in the Effect of Acetylcholine on the Electrical Activity of Venom-Treated Axons

    PubMed Central

    Rosenberg, Philip; Hoskin, F. C. G.

    1963-01-01

    D-Tubocurarine (curare) and acetylcholine (ACh) had been found to block electrical activity after treatment of squid giant axons with cottonmouth moccasin venom at a concentration which had no effect on conduction. It has now been demonstrated that this effect is attributable to reduction of permeability barriers. The penetration of externally applied C14-labeled dimethylcurare, ACh, choline, and trimethylamine into the axoplasm of the squid giant axon was determined in axons treated with either cottonmouth, rattlesnake, or bee venom, and in untreated control axons. The lipid-soluble tertiary nitrogen compound trimethylamine readily penetrated into the axoplasm of untreated axons. In contrast, after exposure of the axons to the lipid-insoluble quaternary nitrogen compounds for 1 hour their presence in the axoplasm was hardly detectable (less than 1 per cent). However, following 15µg/ml cottonmouth venom 1 to 5 per cent of their external concentration is found within the axoplasm while following 50µg/ml venom 10 to 50 per cent enters. The penetration of dimethylcurare is also increased by 10 µg/ml bee venom but not by 1 µg/ml bee venom nor 1000 µg/ml rattlesnake venom. The experiments show that when ACh and curare, following venom treatment, affect electrical activity, they also penetrate into the axon. Treatments which do not increase penetration are also ineffective in rendering the compounds active. PMID:13974908

  20. DL0410 Ameliorates Memory and Cognitive Impairments Induced by Scopolamine via Increasing Cholinergic Neurotransmission in Mice.

    PubMed

    Lian, Wenwen; Fang, Jiansong; Xu, Lvjie; Zhou, Wei; Kang, De; Xiong, Wandi; Jia, Hao; Liu, Ai-Lin; Du, Guan-Hua

    2017-03-06

    Deficiency of the cholinergic system is thought to play a vital role in cognitive impairment of dementia. DL0410 was discovered as a dual inhibitor of acetylcholinesterase (AChE) and butyrylcholinestease (BuChE), with potent efficiency in in-vitro experiments, but its in vivo effect on the cholinergic model has not been evaluated, and its action mechanism has also not been illustrated. In the present study, the capability of DL0410 in ameliorating the amnesia induced by scopolamine was investigated, and its effect on the cholinergic system in the hippocampus and its binding mode in the active site of AChE was also explored. Mice were administrated DL0410 (3 mg/kg, 10 mg/kg, and 30 mg/kg), and mice treated with donepezil were used as a positive control. The Morris water maze, escape learning task, and passive avoidance task were used as behavioral tests. The test results indicated that DL0410 could significantly improve the learning and memory impairments induced by scopolamine, with 10 mg/kg performing best. Further, DL0410 inhibited the AChE activity and increased acetylcholine (ACh) levels in a dose-dependent manner, and interacted with the active site of AChE in a similar manner as donepezil. However, no difference in the activity of BuChE was found in this study. All of the evidence indicated that its AChE inhibition is an important mechanism in the anti-amnesia effect. In conclusion, DL0410 could be an effective therapeutic drug for the treatment of dementia, especially Alzheimer's disease.

  1. Exercise Sandals Increase Lower Extremity Electromyographic Activity During Functional Activities

    PubMed Central

    Hirth, Christopher J.; Guskiewicz, Kevin M.

    2003-01-01

    Objective: Anecdotal evidence suggests that use of Exercise Sandals results in a number of positive clinical outcomes. However, little research has been conducted to determine their efficacy objectively. Our purposes were to determine the effect of Exercise Sandals on lower leg electromyography (EMG) during activities in the Exercise Sandals and to compare EMG associated with Exercise Sandals with traditional lower extremity rehabilitation exercises. Design and Setting: Two within-subjects, repeated-measures designs were used to identify differences in lower extremity EMG: (1) between activities with and without Exercise Sandals and (2) between Exercise Sandals activities and traditional rehabilitation activities. All data were collected in the Sports Medicine Research Laboratory. Subjects: Eighteen subjects involved in rehabilitation using Exercise Sandals for at least 2 weeks within the year before data collection. Measurements: Mean EMG amplitudes from the tibialis anterior, peroneus longus, soleus, and lateral gastrocnemius muscles were measured during single-leg stance, side stepping, and “high knees,” all performed with and without the Exercise Sandals, as well as single-leg stance on a foam surface and T-band kicks in the sagittal and frontal planes. Results: Exercise Sandals increased lower leg EMG activity, particularly in the ankle invertors and evertors. Also, activities involving the Exercise Sandals resulted in EMG activity similar to or exceeding that associated with traditional ankle-rehabilitation exercises. Conclusions: These results, coupled with the fact that Exercise Sandals are used in a functional closed kinetic chain manner, suggest that they are an effective means of increasing lower extremity muscle activity. PMID:14608427

  2. RNAi of ace1 and ace2 in Blattella germanica reveals their differential contribution to acetylcholinesterase activity and sensitivity to insecticides.

    PubMed

    Revuelta, L; Piulachs, M D; Bellés, X; Castañera, P; Ortego, F; Díaz-Ruíz, J R; Hernández-Crespo, P; Tenllado, F

    2009-12-01

    Cyclorrhapha insect genomes contain a single acetylcholinesterase (AChE) gene while other insects contain at least two ace genes (ace1 and ace2). In this study we tested the hypothesis that the two ace paralogous from Blattella germanica have different contributions to AChE activity, using RNA interference (RNAi) to knockdown each one individually. Paralogous-specific depletion of Bgace transcripts was evident in ganglia of injected cockroaches, although the effects at the protein level were less pronounced. Using spectrophotometric and zymogram measurements, we obtained evidence that BgAChE1 represents 65-75% of the total AChE activity in nerve tissue demonstrating that ace1 encodes a predominant AChE. A significant increase in sensitivity of Bgace1-interfered cockroaches was observed after 48 h of exposure to chlorpyrifos. In contrast, Bgace2 knockdown had a negligible effect on mortality to this organophosphate. These results point out a key role, qualitative and/or quantitative, of AChE1 as target of organophosphate insecticides in this species. Silencing the expression of Bgace1 but not Bgace2 also produced an increased mortality in insects when synergized with lambda-cyhalothrin, a situation which resembles the synergistic effects observed between organophosphates and pyrethroids. Gene silencing of ace genes by RNAi offers an exciting approach for examining a possible functional differentiation in ace paralogous.

  3. Myasthenia Gravis and the Tops and Bottoms of AChRs Antigenic Structure of the MIR and Specific Immunosuppression of EAMG Using AChR Cytoplasmic Domains

    PubMed Central

    Lindstrom, Jon; Luo, Jie; Kuryatov, Alexander

    2009-01-01

    The main immunogenic region (MIR), against which half or more of the autoantibodies to acetylcholine receptors (AChRs) in myasthenia gravis (MG) or experimental autoimmune MG (EAMG) are directed, is located at the extracellular end of α1 subunits. Rat monoclonal antibodies (mAbs) to the MIR efficiently compete with MG patient autoantibodies for binding to human muscle AChRs. Antibodies bound to the MIR do not interfere with cholinergic ligand binding or AChR function, but target complement and trigger antigenic modulation. Rat mAbs to the MIR also bind to human ganglionic AChR α3 subunits, but MG patient antibodies do not. By making chimeras of α1 subunits with α7 subunits or ACh binding protein, the structure of the MIR and its functional effects are being investigated. Many mAbs to the MIR bind only to the native conformation of α1 subunits because they bind to sequences that are adjacent only in the native structure. The MIR epitopes recognized by these mAbs are not recognized by most patient antibodies whose epitopes must be nearby. The presence of the MIR epitopes in α1/α7 chimeras greatly promotes AChR expression and sensitivity to activation. EAMG can be suppressed by treatment with denatured, bacterially expressed mixtures of extracellular and cytoplasmic domains of human α1, β1, γ, δ, and ε subunits. A mixture of only the cytoplasmic domains not only avoids the potential liability of provoking formation antibodies to pathologically significant epitopes on the extracellular surface, but also potently suppresses the development of EAMG. PMID:18567851

  4. School Programs to Increase Physical Activity

    ERIC Educational Resources Information Center

    Lee, Amelia; Solmon, Melinda

    2007-01-01

    A quality physical education program is at the heart of any plan to promote lifelong participation in physical activity, but it has become evident at many schools that physical education specialists alone cannot address the physical activity needs of children. This is why a series of studies were conducted to develop strategies for the…

  5. Acetylcholinesterase activity in the cerebrospinal fluid of dogs with seizures.

    PubMed

    Chai, Orit; Sommer, Adi; Zimmerman, Gabriel; Soreq, Hermona; Friedman, Alon; Bdolah-Abram, Tali; Aroch, Itamar; Shamir, Merav H

    2013-10-01

    Recent studies in animal models have focused on the role of cholinergic elements, mainly acetylcholinesterase (AChE) and the 'readthrough' acetylcholinesterase isoform (AChE-R), in seizures. A prospective double-masked study was conducted to assess the activity of AChE and AChE-R in cerebrospinal fluid (CSF) of 26 dogs post-seizure, 28 dogs with intervertebral disc disease (IVDD) and 16 healthy dogs. AChE was also measured in the serum in the post-seizure and IVDD groups. The results showed no significant differences in CSF AChE among the three groups. AChE-R was not detected in any dog and AChE in the serum was similar between groups. This preliminary study provides new information on AChE and AChE-R in the CSF and sera of dogs following naturally-occurring seizures.

  6. Acetylcholinesterase Activity and Neurodevelopment in Boys and Girls

    PubMed Central

    Himes, John H.; Jacobs, David R.; Alexander, Bruce H.; Gunnar, Megan R.

    2013-01-01

    BACKGROUND: Organophosphate exposures can affect children’s neurodevelopment, possibly due to neurotoxicity induced by acetylcholinesterase (AChE) inhibition, and may affect boys more than girls. We tested the hypothesis that lower AChE activity is associated with lower neurobehavioral development among children living in Ecuadorian floricultural communities. METHODS: In 2008, we examined 307 children (age: 4–9 years; 52% male) and quantified AChE activity and neurodevelopment in 5 domains: attention/executive functioning, language, memory/learning, visuospatial processing, and sensorimotor (NEPSY-II test). Associations were adjusted for demographic and socioeconomic characteristics and height-for-age, flower worker cohabitation, and hemoglobin concentration. RESULTS: Mean ± standard deviation AChE activity was 3.14 ± 0.49 U/mL (similar for both genders). The range of scores among neurodevelopment subtests was 5.9 to 10.7 U (standard deviation: 2.6–4.9 U). Girls had a greater mean attention/executive functioning domain score than boys. In boys only, there were increased odds ratios of low (<9th percentile) neurodevelopment among those in the lowest tertile versus the highest tertile of AChE activity (odds ratios: total neurodevelopment: 5.14 [95% confidence interval (CI): 0.84 to 31.48]; attention/executive functioning domain: 4.55 [95% CI: 1.19 to 17.38], memory/learning domain: 6.03 [95% CI: 1.17 to 31.05]) after adjustment for socioeconomic and demographic factors, height-for-age, and hemoglobin. Within these domains, attention, inhibition and long-term memory subtests were most affected. CONCLUSIONS: Low AChE activity was associated with deficits in neurodevelopment, particularly in attention, inhibition, and memory in boys but not in girls. These critical cognitive skills affect learning and academic performance. Added precautions regarding secondary occupational pesticide exposure would be prudent. PMID:24249815

  7. Residues Responsible for the Selectivity of α-Conotoxins for Ac-AChBP or nAChRs

    PubMed Central

    Lin, Bo; Xiang, Shihua; Li, Mengsen

    2016-01-01

    Nicotinic acetylcholine receptors (nAChRs) are targets for developing new drugs to treat severe pain, nicotine addiction, Alzheimer disease, epilepsy, etc. α-Conotoxins are biologically and chemically diverse. With 12–19 residues and two disulfides, they can be specifically selected for different nAChRs. Acetylcholine-binding proteins from Aplysia californica (Ac-AChBP) are homologous to the ligand-binding domains of nAChRs and pharmacologically similar. X-ray structures of the α-conotoxin in complex with Ac-AChBP in addition to computer modeling have helped to determine the binding site of the important residues of α-conotoxin and its affinity for nAChR subtypes. Here, we present the various α-conotoxin residues that are selective for Ac-AChBP or nAChRs by comparing the structures of α-conotoxins in complex with Ac-AChBP and by modeling α-conotoxins in complex with nAChRs. The knowledge of these binding sites will assist in the discovery and design of more potent and selective α-conotoxins as drug leads. PMID:27727162

  8. Increased ABCA1 activity protects against atherosclerosis.

    PubMed

    Singaraja, Roshni R; Fievet, Catherine; Castro, Graciela; James, Erick R; Hennuyer, Nathalie; Clee, Susanne M; Bissada, Nagat; Choy, Jonathan C; Fruchart, Jean-Charles; McManus, Bruce M; Staels, Bart; Hayden, Michael R

    2002-07-01

    The ABC transporter ABCA1 plays a key role in the first steps of the reverse cholesterol transport pathway by mediating lipid efflux from macrophages. Previously, it was demonstrated that human ABCA1 overexpression in vivo in transgenic mice results in a mild elevation of plasma HDL levels and increased efflux of cholesterol from macrophages. In this study, we determined the effect of overexpression of ABCA1 on atherosclerosis development. Human ABCA1 transgenic mice (BAC(+)) were crossed with ApoE(-/-) mice, a strain that spontaneously develop atherosclerotic lesions. BAC(+)ApoE(-/-) mice developed dramatically smaller, less-complex lesions as compared with their ApoE(-/-) counterparts. In addition, there was increased efflux of cholesterol from macrophages isolated from the BAC(+)ApoE(-/-) mice. Although the increase in plasma HDL cholesterol levels was small, HDL particles from BAC(+)ApoE(-/-) mice were significantly better acceptors of cholesterol. Lipid analysis of HDL particles from BAC(+)ApoE(-/-) mice revealed an increase in phospholipid levels, which was correlated significantly with their ability to enhance cholesterol efflux.

  9. Can hydroxylamine be a more potent nucleophile for the reactivation of tabun-inhibited AChE than prototype oxime drugs? An answer derived from quantum chemical and steered molecular dynamics studies.

    PubMed

    Lo, Rabindranath; Ganguly, Bishwajit

    2014-07-29

    Organophosphorus nerve agents are highly toxic compounds which strongly inhibit acetylcholinesterase (AChE) in the blood and in the central nervous system (CNS). Tabun is one of the highly toxic organophosphorus (OP) compounds and is resistant to many oxime drugs formulated for the reactivation of AChE. The reactivation mechanism of tabun-conjugated AChE with various drugs has been examined with density functional theory and ab initio quantum chemical calculations. The presence of a lone-pair located on the amidic group resists the nucleophilic attack at the phosphorus center of the tabun-conjugated AChE. We have shown that the newly designed drug candidate N-(pyridin-2-yl)hydroxylamine, at the MP2/6-31+G*//M05-2X/6-31G* level in the aqueous phase with the polarizable continuum solvation model (PCM), is more effective in reactivating the tabun-conjugated AChE than typical oxime drugs. The rate determining activation barrier with N-(pyridin-2-yl)hydroxylamine was found to be ∼1.7 kcal mol(-1), which is 7.2 kcal mol(-1) lower than the charged oxime trimedoxime (one of the most efficient reactivators in tabun poisonings). The greater nucleophilicity index (ω(-)) and higher CHelpG charge of pyridinylhydroxylamine compared to TMB4 support this observation. Furthermore, we have also examined the reactivation process of tabun-inhibited AChE with some other bis-quaternary oxime drug candidates such as methoxime (MMB4) and obidoxime. The docking analysis suggests that charged bis-quaternary pyridinium oximes have greater binding affinity inside the active-site gorge of AChE compared to the neutral pyridinylhydroxylamine. The peripheral ligand attached to the neutral pyridinylhydroxylamine enhanced the binding with the aromatic residues in the active-site gorge of AChE through effective π-π interactions. Steered molecular dynamics (SMD) simulations have also been performed with the charged oxime (TMB4) and the neutral hydroxylamine. From protein-drug interaction

  10. Increased Rho-kinase expression and activity and pulmonary endothelial dysfunction in smokers with normal lung function.

    PubMed

    Duong-Quy, S; Dao, P; Hua-Huy, T; Guilluy, C; Pacaud, P; Dinh-Xuan, A T

    2011-02-01

    Endothelial dysfunction is one of the main consequences of the toxic effects of cigarette smoke on the vascular system. Increasing evidence suggests that the small G-protein RhoA and its downstream effectors, the Rho-kinases (ROCKs), are involved in systemic endothelial dysfunction induced by cigarette smoke. This study aimed to evaluate the role of the RhoA/ROCKs pathway in pulmonary artery endothelial function in current smokers with normal lung function. Lung tissues were obtained from nonsmokers and smokers who underwent lobectomy for lung carcinoma. Arterial relaxation in response to acetylcholine (ACh) was assessed in isolated pulmonary arterial rings. Protein expressions and activities of endothelial nitric oxide synthase (eNOS), ROCKs and the myosin phosphatase subunit 1 (MYPT-1) were sought. Relaxation in response to ACh was significantly lower in smokers as compared with nonsmokers (n = 8 in each group), consistent with reduced eNOS activity in the former compared with the latter. eNOS protein expression remained, however, the same in both groups. Expression of ROCKs, guanosine triphosphate-RhoA and phosphorylated MYPT-1 were significantly increased in smokers compared with controls. Pulmonary endothelial dysfunction is present in smokers whose lung function has not yet been impaired. Reduced activity of eNOS accounts at least in part for this endothelial dysfunction. Increased expression and activity of ROCKs accounts for another part through direct or indirect inhibition of the Rho-A/ROCKs pathway on nitric oxide synthesis and sustained pulmonary vasoconstriction through inhibition of myosin phosphatase.

  11. Constitutively Active Acetylcholine-Dependent Potassium Current Increases Atrial Defibrillation Threshold by Favoring Post-Shock Re-Initiation.

    PubMed

    Bingen, Brian O; Askar, Saïd F A; Neshati, Zeinab; Feola, Iolanda; Panfilov, Alexander V; de Vries, Antoine A F; Pijnappels, Daniël A

    2015-10-21

    Electrical cardioversion (ECV), a mainstay in atrial fibrillation (AF) treatment, is unsuccessful in up to 10-20% of patients. An important aspect of the remodeling process caused by AF is the constitutive activition of the atrium-specific acetylcholine-dependent potassium current (IK,ACh → IK,ACh-c), which is associated with ECV failure. This study investigated the role of IK,ACh-c in ECV failure and setting the atrial defibrillation threshold (aDFT) in optically mapped neonatal rat cardiomyocyte monolayers. AF was induced by burst pacing followed by application of biphasic shocks of 25-100 V to determine aDFT. Blocking IK,ACh-c by tertiapin significantly decreased DFT, which correlated with a significant increase in wavelength during reentry. Genetic knockdown experiments, using lentiviral vectors encoding a Kcnj5-specific shRNA to modulate IK,ACh-c, yielded similar results. Mechanistically, failed ECV was attributed to incomplete phase singularity (PS) removal or reemergence of PSs (i.e. re-initiation) through unidirectional propagation of shock-induced action potentials. Re-initiation occurred at significantly higher voltages than incomplete PS-removal and was inhibited by IK,ACh-c blockade. Whole-heart mapping confirmed our findings showing a 60% increase in ECV success rate after IK,ACh-c blockade. This study provides new mechanistic insight into failing ECV of AF and identifies IK,ACh-c as possible atrium-specific target to increase ECV effectiveness, while decreasing its harmfulness.

  12. Constitutively Active Acetylcholine-Dependent Potassium Current Increases Atrial Defibrillation Threshold by Favoring Post-Shock Re-Initiation

    PubMed Central

    Bingen, Brian O.; Askar, Saïd F. A.; Neshati, Zeinab; Feola, Iolanda; Panfilov, Alexander V.; de Vries, Antoine A. F.; Pijnappels, Daniël A.

    2015-01-01

    Electrical cardioversion (ECV), a mainstay in atrial fibrillation (AF) treatment, is unsuccessful in up to 10–20% of patients. An important aspect of the remodeling process caused by AF is the constitutive activition of the atrium-specific acetylcholine-dependent potassium current (IK,ACh → IK,ACh-c), which is associated with ECV failure. This study investigated the role of IK,ACh-c in ECV failure and setting the atrial defibrillation threshold (aDFT) in optically mapped neonatal rat cardiomyocyte monolayers. AF was induced by burst pacing followed by application of biphasic shocks of 25–100 V to determine aDFT. Blocking IK,ACh-c by tertiapin significantly decreased DFT, which correlated with a significant increase in wavelength during reentry. Genetic knockdown experiments, using lentiviral vectors encoding a Kcnj5-specific shRNA to modulate IK,ACh-c, yielded similar results. Mechanistically, failed ECV was attributed to incomplete phase singularity (PS) removal or reemergence of PSs (i.e. re-initiation) through unidirectional propagation of shock-induced action potentials. Re-initiation occurred at significantly higher voltages than incomplete PS-removal and was inhibited by IK,ACh-c blockade. Whole-heart mapping confirmed our findings showing a 60% increase in ECV success rate after IK,ACh-c blockade. This study provides new mechanistic insight into failing ECV of AF and identifies IK,ACh-c as possible atrium-specific target to increase ECV effectiveness, while decreasing its harmfulness. PMID:26487066

  13. A selective allosteric potentiator of the M1 muscarinic acetylcholine receptor increases activity of medial prefrontal cortical neurons and restores impairments in reversal learning.

    PubMed

    Shirey, Jana K; Brady, Ashley E; Jones, Paulianda J; Davis, Albert A; Bridges, Thomas M; Kennedy, J Phillip; Jadhav, Satyawan B; Menon, Usha N; Xiang, Zixiu; Watson, Mona L; Christian, Edward P; Doherty, James J; Quirk, Michael C; Snyder, Dean H; Lah, James J; Levey, Allan I; Nicolle, Michelle M; Lindsley, Craig W; Conn, P Jeffrey

    2009-11-11

    M(1) muscarinic acetylcholine receptors (mAChRs) may represent a viable target for treatment of disorders involving impaired cognitive function. However, a major limitation to testing this hypothesis has been a lack of highly selective ligands for individual mAChR subtypes. We now report the rigorous molecular characterization of a novel compound, benzylquinolone carboxylic acid (BQCA), which acts as a potent, highly selective positive allosteric modulator (PAM) of the rat M(1) receptor. This compound does not directly activate the receptor, but acts at an allosteric site to increase functional responses to orthosteric agonists. Radioligand binding studies revealed that BQCA increases M(1) receptor affinity for acetylcholine. We found that activation of the M(1) receptor by BQCA induces a robust inward current and increases spontaneous EPSCs in medial prefrontal cortex (mPFC) pyramidal cells, effects which are absent in acute slices from M(1) receptor knock-out mice. Furthermore, to determine the effect of BQCA on intact and functioning brain circuits, multiple single-unit recordings were obtained from the mPFC of rats that showed BQCA increases firing of mPFC pyramidal cells in vivo. BQCA also restored discrimination reversal learning in a transgenic mouse model of Alzheimer's disease and was found to regulate non-amyloidogenic APP processing in vitro, suggesting that M(1) receptor PAMs have the potential to provide both symptomatic and disease modifying effects in Alzheimer's disease patients. Together, these studies provide compelling evidence that M(1) receptor activation induces a dramatic excitation of PFC neurons and suggest that selectively activating the M(1) mAChR subtype may ameliorate impairments in cognitive function.

  14. Modulation of nicotinic receptor activity in the central nervous system: a novel approach to the treatment of Alzheimer disease.

    PubMed

    Albuquerque, E X; Santos, M D; Alkondon, M; Pereira, E F; Maelicke, A

    2001-08-01

    Impaired cholinergic function in the central nervous system is an early feature of Alzheimer disease (AD). Currently, cholinergic deficit is usually corrected by increasing the amount of acetylcholine in the synapse by inhibiting acetylcholinesterase (AChE). One of the most consistent cholinergic deficits in AD is the reduced expression of nicotinic acetylcholine receptors (nAChR) in the brain. Since these receptors are essential for learning and memory, restoring nicotinic cholinergic function is a promising approach to treating AD. Allosteric modulation of nAChR is a novel approach, which circumvents development of tolerance through long-term use of conventional nicotinic agonists. Allosteric modulators interact with receptor-binding sites distinct from those capable of recognizing the natural agonist. Positive allosteric modulation of nAChR activity has no effect on conductance of single channels; instead, by facilitating channel opening, it potentiates responses evoked by the interaction of the natural agonist with presynaptic and postsynaptic nAChR. Allosteric modulation of nAChR activity could therefore potentially produce a significant benefit in AD. One such allosteric modulator is galantamine. In addition to increasing nAChR activity, galantamine also inhibits AChE. This novel, dual mechanism of action distinguishes galantamine from many other AChE inhibitors. Galantamine has been shown to improve cognitive and daily function for at least 6 months in placebo-controlled trials, and to maintain these functions at baseline levels for at least 12 months in a 6-month open-label extension study. Galantamine has positive effects on nAChR expression, which are likely to contribute to its sustained efficacy in the treatment of AD patients.

  15. Two rare variations, D478N and D478E, that occur at the same amino acid residue in nicotinic acetylcholine receptor (nAChR) α2 subunit influence nAChR function.

    PubMed

    Dash, Bhagirathi; Li, Ming D

    2014-10-01

    There occur two rare variations, Asp(D)478Asn(N) and Asp(D)478Glu(E), in the putative cytoplasmic amphipathic α-helices of human nicotinic acetylcholine receptor (nAChR) α2 subunit as a result of mutation in the 1st (G → A: rs141072985) and 3rd (C → A: rs56344740) nucleotide of its 478th triplet codon (GAC). We assessed the effects of these two variations on the function of α2β2- and α2β4-nAChRs as they could alter the electronegativity and/or the structure of the cytoplasmic 'portals' (framed by subunit amphipathic α-helices) necessary for obligate ion permeation from extracellular space to cytoplasm. We injected decreasing ratio of subunit cRNAs (α:β; 10:1, 1:1 and 1:10) into Xenopus oocytes to express putative low-sensitivity (LS; 10:1), intermediate-sensitivity (IS; 1:1) and high sensitivity (HS; 1:10) isoforms of wild type and variant α2β2- and α2β4-nAChRs. Two-electrode voltage clamp analyses indicate that the agonist (ACh or nicotine) induced peak current responses (Imax) of α2β2-nAChR isoforms and those of α2β4-nAChR isoforms are increased (1.3-4.7-fold) as a result of D478E variation. The α2 subunit D478N variation only increases the Imax of IS (∼2-fold) or HS (1.4-2.1-fold) α2β2-nAChRs. Concentration-response curves constructed indicate no effect on agonist sensitivities of LS and HS isoforms of α2β2- or α2β4-nAChRs as a result of either variation in α2 subunit. Between the two variant nAChRs, α2(D478E)*-nAChR isoforms generally yield higher Imax than those of respective α2(D478N)*-nAChR isoforms. These effects could be attributed to alteration in cytoplasmic 'portals' and/or ion permeation through it owing to change in amino acid electronegativity (D → N) and side chain length (D → E) in nAChR α2 subunit.

  16. Pre-treatment with ebselen and vitamin E modulate acetylcholinesterase activity: interaction with demyelinating agents.

    PubMed

    Mazzanti, Cinthia M; Spanevello, Roselia; Ahmed, Musthaq; Pereira, Luciane B; Gonçalves, Jamile F; Corrêa, Maisa; Schmatz, Roberta; Stefanello, Naiara; Leal, Daniela B R; Mazzanti, Alexandre; Ramos, Adriano T; Martins, Tessie B; Danesi, Cristiane Cademartori; Graça, Dominguita L; Morsch, Vera M; Schetinger, Maria Rosa C

    2009-02-01

    The ethidium bromide (EB) demyelinating model was associated with vitamin E (Vit E) and ebselen (Ebs) treatment to evaluate acetylcholinesterase (AChE) activity in the striatum (ST), hippocampus (HP), cerebral cortex (CC) and erythrocytes. Rats were divided into seven groups: I-Control (saline), II-(canola); III-(Ebs), IV-(Vit E); V-(EB); VI-(EB+Ebs) and VII-(EB+Vit E). At 3 days after the EB injection, AChE activity in the CC and HC was significantly reduced in groups III, IV, V, VI and VII (p<0.05) and in the ST it was reduced in groups III and V (p<0.05) when compared to the control group. At 21 days after the EB injection, AChE activity in the CC was significantly reduced in groups III, IV and V, while in groups VI and VII a significant increase was observed when compared to the control group. In the HC and ST, AChE activity was significantly reduced in groups V, VI and VII when compared to the control group (p<0.05). In the erythrocytes, at 3 days after the EB injection, AChE activity was significantly reduced in groups III, IV, V, VI and VII and at 21 days there was a significant reduction only in groups VI and VII (p<0.05) when compared to the control group. In conclusion, this study demonstrated that Ebs and Vit E interfere with the cholinergic neurotransmission by altering AChE activity in the different brain regions and in the erythrocytes. Furthermore, treatment with Vit E and Ebs protected against the demyelination lesion caused by EB. In this context, we can suggest that ebselen and Vit E should be considered potential therapeutics and scientific tools to be investigated in brain disorders associated with demyelinating events.

  17. Acetylcholine elongates neuronal growth cone filopodia via activation of nicotinic acetylcholine receptors.

    PubMed

    Zhong, Lei Ray; Estes, Stephen; Artinian, Liana; Rehder, Vincent

    2013-07-01

    In addition to acting as a classical neurotransmitter in synaptic transmission, acetylcholine (ACh) has been shown to play a role in axonal growth and growth cone guidance. What is not well understood is how ACh acts on growth cones to affect growth cone filopodia, structures known to be important for neuronal pathfinding. We addressed this question using an identified neuron (B5) from the buccal ganglion of the pond snail Helisoma trivolvis in cell culture. ACh treatment caused pronounced filopodial elongation within minutes, an effect that required calcium influx and resulted in the elevation of the intracellular calcium concentration ([Ca]i ). Whole-cell patch clamp recordings showed that ACh caused a reduction in input resistance, a depolarization of the membrane potential, and an increase in firing frequency in B5 neurons. These effects were mediated via the activation of nicotinic acetylcholine receptors (nAChRs), as the nAChR agonist dimethylphenylpiperazinium (DMPP) mimicked the effects of ACh on filopodial elongation, [Ca]i elevation, and changes in electrical activity. Moreover, the nAChR antagonist tubucurarine blocked all DMPP-induced effects. Lastly, ACh acted locally at the growth cone, because growth cones that were physically isolated from their parent neuron responded to ACh by filopodial elongation with a similar time course as growth cones that remained connected to their parent neuron. Our data revealed a critical role for ACh as a modulator of growth cone filopodial dynamics. ACh signaling was mediated via nAChRs and resulted in Ca influx, which, in turn, caused filopodial elongation.

  18. Anti-inflammatory role of microglial alpha7 nAChRs and its role in neuroprotection.

    PubMed

    Egea, Javier; Buendia, Izaskun; Parada, Esther; Navarro, Elisa; León, Rafael; Lopez, Manuela G

    2015-10-15

    Nicotinic acetylcholine receptors (nAChRs) are widely distributed throughout the central nervous system, being expressed in neurons and non-neuronal cells, where they participate in a variety of physiological responses like memory, learning, locomotion, attention, among others. We will focus on the α7 nAChR subtype, which has been implicated in neuroprotection, synaptic plasticity and neuronal survival, and is considered as a potential therapeutic target for several neurological diseases. Oxidative stress and neuroinflammation are currently considered as two of the most important pathological mechanisms common in neurodegenerative diseases such as Alzheimer, Parkinson or Huntington diseases. In this review, we will first analysed the distribution and expression of nAChR in mammalian brain. Then, we focused on the function of the α7 nAChR subtype in neuronal and non-neuronal cells and its role in immune responses (cholinergic anti-inflammatory pathway). Finally, we will revise the anti-inflammatory pathway promoted via α7 nAChR activation that is related to recruitment and activation of Jak2/STAT3 pathway, which on the one hand inhibits NF-κB nuclear translocation, and on the other hand, activates the master regulator of oxidative stress Nrf2/HO-1. This review provides a profound insight into the role of the α7 nAChR subtype in microglia and point out to microglial α7/HO-1 pathway as an anti-inflammatory therapeutic target.

  19. α7nAChR is expressed in satellite cells at different myogenic status during skeletal muscle wound healing in rats.

    PubMed

    Tian, Zhi-Ling; Jiang, Shu-Kun; Zhang, Miao; Wang, Meng; Li, Jiao-Yong; Zhao, Rui; Wang, Lin-Lin; Liu, Min; Li, Shan-Shan; Zhang, Meng-Zhou; Guan, Da-Wei

    2015-12-01

    Recent study has reported that α7 nicotine acetylcholine receptor (α7nAChR) is expressed in regenerated multinucleated myotubes. But the distribution of α7nAChR in satellite cells in different myogenic status is unknown. A preliminary study on the dynamic distribution of α7nAChR in satellite cells was performed by double indirect immunofluorescent procedures during skeletal muscle wound healing in rats. An animal model of skeletal muscle contusion was established in 40 Sprague-Dawley male rats. Samples were taken at 1, 3, 5, 7, 9, 13, 17 and 21 days after injury, respectively (five rats in each posttraumatic interval). Five rats were employed as control. In normal muscle specimens, weak immunoreactivity for α7nAChR was detected in a few satellite cells (considered as quiescent). α7nAChR-positive signals were observed in proliferated and differentiated satellite cells and regenerated multinucleated myotubes in the wounded areas. By morphometric analysis, the average number of α7nAChR+/Pax7+ and α7nAChR+/MyoD+ cells climaxed at 5 days post-injury. The average number of α7nAChR+/myogenin+ cells was significantly increased from 3 to 9 days post-injury as compared with other posttraumatic intervals. The protein level of α7nAChR maximized at 9 days post-injury, which implies that α7nAChR was associated with the satellite cells status. Our observations on expression of α7nAChR in satellite cells from quiescence to myotube formation suggest that α7nAChR may be involved in muscle regeneration by regulating satellite cell status.

  20. Pyridoxine-resveratrol hybrids Mannich base derivatives as novel dual inhibitors of AChE and MAO-B with antioxidant and metal-chelating properties for the treatment of Alzheimer's disease.

    PubMed

    Yang, Xia; Qiang, Xiaoming; Li, Yan; Luo, Li; Xu, Rui; Zheng, Yunxiaozhu; Cao, Zhongcheng; Tan, Zhenghuai; Deng, Yong

    2017-04-01

    A series of pyridoxine-resveratrol hybrids Mannich base derivatives as multifunctional agents have been designed, synthesized and evaluated for cholinesterase (ChE) and monoamine oxidase (MAO) inhibitory activity. To further explore the multifunctional properties of the new derivatives, their antioxidant activities and metal-chelating properties were also tested. The results showed that most of these compounds could selectively inhibit acetylcholinesterase (AChE) and MAO-B. Among them, compounds 7d and 8b exhibited the highest potency for AChE inhibition with IC50 values of 2.11μM and 1.56μM, respectively, and compound 7e exhibited the highest MAO-B inhibition with an IC50 value of 2.68μM. The inhibition kinetic analysis revealed that compound 7d showed a mixed-type inhibition, binding simultaneously to the CAS and PAS of AChE. Molecular modeling study was also performed to investigate the binding mode of these hybrids with MAO-B. In addition, all target compounds displayed good antioxidant and metal-chelating properties. Taken together, these preliminary findings can be a new starting point for further development of multifunctional agents for Alzheimer's disease.

  1. How Active Are Your Students? Increasing Physical Activity in Schools

    ERIC Educational Resources Information Center

    Avery, Marybell; Brandt, Janet

    2010-01-01

    The U. S. Department of Health and Human Services recommends that youth engage in at least 60 minutes of physical activity each day, most of which should be either moderate- or vigorous-intensity aerobic physical activity. Half of this amount (30 minutes) should be achieved during the school day. NASPE provides guidance in the form of a…

  2. Cholinesterase inhibitors: SAR and enzyme inhibitory activity of 3-[omega-(benzylmethylamino)alkoxy]xanthen-9-ones.

    PubMed

    Piazzi, Lorna; Belluti, Federica; Bisi, Alessandra; Gobbi, Silvia; Rizzo, Stefano; Bartolini, Manuela; Andrisano, Vincenza; Recanatini, Maurizio; Rampa, Angela

    2007-01-01

    In this work, we further investigated a previously introduced class of cholinesterase inhibitors. The removal of the carbamic function from the lead compound xanthostigmine led to a reversible cholinesterase inhibitors 3. Some new 3-[omega-(benzylmethylamino)alkoxy]xanthen-9-one analogs were designed, synthesized, and evaluated for their inhibitory activity against both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE). The length of the alkoxy chain of compound 3 was increased and different substituents were introduced. From the IC(50) values, it clearly appears that the carbamic residue is crucial to obtain highly potent AChE inhibitors. On the other hand, peculiarity of these compounds is the high selectivity toward BuChE with respect to AChE, being compound 12 the most selective one (6000-fold). The development of selective BuChE inhibitors may be of great interest to clarify the physiological role of this enzyme and to provide novel therapeutics for various diseases.

  3. Acetylcholinesterases of Rhipicephalus (Boophilus) microplus – Multiple gene expression presents an opportune model system for elucidation of multiple functions of AChEs.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acetylcholinesterase (AChE) is a key neural enzyme of both vertebrates and invertebrates, and is the biochemical target of organophosphate and carbamate pesticides for invertebrates, as well as vertebrate nerve agents, e.g., soman, tabun, VX, and others. AChE inhibitors are also key drugs among thos...

  4. Longitudinal study of tuberculosis outcomes among immunologically naive Aché natives of Paraguay.

    PubMed

    Hurtado, A Magdalena; Hill, Kim R; Rosenblatt, Wilhelm; Bender, Jacquelyn; Scharmen, Tom

    2003-06-01

    This study documents the course of a tuberculosis epidemic in an immunologically naive group of South American Indians within fewer than 20 years after first sustained contact with outsiders. Groups of Northern Aché (ah-CHAY) of eastern Paraguay were contacted and settled on reservations between 1971-1979. Not surprisingly, the Aché are very susceptible to tuberculosis, and the epidemiological characteristics of the disease are quite different from those of populations that have had tuberculosis for centuries. Within 6 years of the first detected case of tuberculosis among the Aché, the prevalence rate of active tuberculosis cases reached 18.2%, and of infected cases among adults, 64.6%, some of the highest rates ever reported for any human group. Remarkably, males and females are equally likely to have been diagnosed with active tuberculosis, Aché children between birth and 5 years of age are least vulnerable to tuberculosis, high nutritional and socioeconomic status do not decrease the risk of disease or infection, and children immunized with BCG are less responsive to tuberculin challenge than are other children. Moreover, similar to the Yanomamö, but unlike populations of European or African descent, a high percentage of Aché with active disease test negative on tuberculin challenge tests (purified protein derivative; PPD). These differences may be due to a high prevalence of diminished cell-mediated immunity, and T-helper 2 dominance. We also hypothesize that these immunological characteristics, low genetic diversity, hostile intergroup interactions, and behavioral noncompliance to treatment protocols together contribute to the high rates of active disease observed. Existing tuberculosis control programs are poorly equipped to handle the impact of these causal complexities on the course of recent tuberculosis epidemics that have quickly spread throughout native communities of Latin America during the last decade.

  5. N-methyl-D-aspartate increases acetylcholine release from rat striatum and cortex: its effect is augmented by choline

    NASA Technical Reports Server (NTRS)

    Ulus, I. H.; Buyukuysal, R. L.; Wurtman, R. J.

    1992-01-01

    We examined the effects of N-methyl-D-aspartate (NMDA), a glutamate agonist, and of glutamate itself, on acetylcholine (ACh) release from superfused rat striatal slices. In a Mg(++)-free medium, NMDA (32-1000 microM) as well as glutamate (1 mM) increased basal ACh release by 35 to 100% (all indicated differences, P less than .05), without altering tissue ACh or choline contents. This augmentation was blocked by Mg++ (1.2 mM) or by MK-801 (10 microM). Electrical stimulation (15 Hz, 75 mA) increased ACh release 9-fold (from 400 to 3660 pmol/mg of protein): this was enhanced (to 4850 pmol/mg of protein) by NMDA (100 microM). ACh levels in stimulated slices fell by 50 or 65% depending on the absence or presence of NMDA. The addition of choline (40 microM) increased ACh release both basally (570 pmol/mg of protein) and with electrical stimulation (6900 pmol/mg of protein). In stimulated slices choline acted synergistically with NMDA, raising ACh release to 10,520 pmol/mg of protein. The presence of choline also blocked the fall in tissue ACh. No treatment affected tissue phospholipid or protein levels. NMDA (32-320 microM) also augmented basal ACh release from cortical but not hippocampal slices. Choline efflux from striatal and cortical (but not hippocampal) slices decreased by 34 to 50% in Mg(++)-free medium. These data indicate that NMDA-like drugs may be useful, particularly in combination with choline, to enhance striatal and cortical cholinergic activity. ACh release from rat hippocampus apparently is not affected by NMDA receptors.

  6. Effect of paraoxonase 1 192 Q/R polymorphism on paraoxonase and acetylcholinesterase enzyme activities in a Turkish population exposed to organophosphate.

    PubMed

    Sunay, Seda Zengin; Kayaaltı, Zeliha; Bayrak, Tülin; Söylemezoğlu, Tülin

    2015-12-01

    Organophosphate (OP) compounds are the most commonly used pesticide groups and they are commercially used in the market for local and industrial purposes. Paraoxonase 1 (PON1) enzyme plays an important role in biotransformation of OP compounds, which shows toxic effects via inhibiting the acetylcholinesterase (AChE). The aim of this study was to determine the effects of PON1 gene polymorphism and its effects on PON and AChE enzyme activities in individuals who were exposed to organophosphorus insecticides due to occupational reasons, and to profile the probability of susceptibility to organophosphorus compounds. For this purpose, 54 individuals who were exposed to OPs and 54 healthy unrelated controls were studied. First, PON1 and AChE enzyme activities were measured. Second, PON1 192 Q/R polymorphism was determined by standard polymerase chain reaction-restriction fragment length polymorphism technique. When the PON1 192 Q/R polymorphism was compared with PON1 enzyme activities, statistically significant association was found in both OP-exposed and control groups (p < 0.05). PON1 192 R(+) (QR + RR genotypes) genotype carriers had higher PON1 activities than 192 R(-) (QQ) genotype carriers. On the other hand, results were statistically analyzed in terms of AChE enzyme activities and there were statistically significant differences only in the OP-exposed group (p < 0.05). The mean AChE concentration in the OP-exposed group was determined as 33.79 ± 6.84 U/g haemoglobin (Hb) for PON1 192 R(+) carriers and 30.37 ± 7.62 U/g Hb for PON1 192 R(+) carriers. As a conclusion, PON1 and AChE activities were increasing according to the genotypes found in individuals having been exposed to OPs at a chronic level; 192 R(+) > 192 R(-), respectively.

  7. Neuronal GABA release and GABA inhibition of ACh release in guinea pig urinary bladder.

    PubMed

    Kusunoki, M; Taniyama, K; Tanaka, C

    1984-04-01

    gamma-Aminobutyric acid (GABA) and glutamate decarboxylase (GAD) are present in the urinary bladder of guinea pigs, and the possible correlation in regional distribution between GABA, GAD, and the number of vesical ganglion cells was studied. Electrical stimulation of the bladder strips produced an increase in the calcium-dependent and tetrodotoxin-sensitive [3H]GABA release and contractions in the strips preloaded with [3H]GABA. Nicotine, acetylcholine chloride (ACh), and hexamethonium did not significantly alter the release of [3H]GABA. Bicuculline significantly enhanced [3H]ACh release and cholinergic components of contractions evoked by electrical stimulation of the bladder strips preloaded with [3H]choline, thereby suggesting that this compound antagonizes the effect of endogenous GABA released during stimulation. GABA and muscimol but not baclofen reduced both the [3H]ACh release and contractions evoked by nicotine. These effects of GABA were antagonized by bicuculline and furosemide but not by alpha- and beta-adrenergic blockers. These findings suggest that GABA may be a noncholinergic nonadrenergic inhibitory neurotransmitter in the urinary bladder. The motility of the urinary bladder is thus inhibited by reducing the release of ACh from the postganglionic cholinergic neurons through bicuculline-sensitive GABA receptors probably associated with the chloride ion channel.

  8. In silico studies on the role of mutant Y337A to reactivate tabun inhibited mAChE with K048.

    PubMed

    Chandar, Nellore Bhanu; Ghosh, Shibaji; Lo, Rabindranath; Banjo, Semire; Ganguly, Bishwajit

    2015-12-05

    Organophosphorus compound (OP) tabun is resistant to reactivate by many oxime drugs after the formation of OP-conjugate with AChE. The reactivation of tabun-inhibited mAChE and site-directed mutants by bispyridinium oxime, K048 (N-[4-(4-hydroxyiminomethylpyridinio)butyl]-4-carbamoylpyridinium dibromide) showed that the mutations significantly poor the overall reactivation efficacy of K048. We have unravelled the lowered efficacy of K048 with the tabun-mutant mAChE(Y337A) using docking and steered molecular dynamics (SMD) simulations. The computed results showed some interesting features for the interaction of drug molecule K048 with tabun-mAChE(wild-type) and tabun-mutant mAChE(Y337A). The SMD simulations showed that the active pyridinium ring of K048 is directed towards the phosphorus atom conjugated to the active serine (SUN203) of tabun-mAChE(wild-type). The cradle shaped residues Tyr337-Phe338 present in the choline binding site stabilize the active pyridinium ring of K048 with π-π interaction and the residue Trp86 involved in T-shaped cation-π interaction. However, in the case of tabun-mutant mAChE(Y337A).K048 conjugate, the replacement of aromatic Tyr337 with the aliphatic alanine unit in the choline binding site, however, loses one of the π-π interaction between the active pyridinium ring of K048 and the Tyr337. The placement of aliphatic alanine unit resulted in the displacement of the side chain of Phe338 towards the His447. Such displacement is causing the inaccessibility of the drug towards the phosphorus atom conjugated to the active serine (SUN203) of tabun-mutant mAChE(Y337A). Furthermore, the unbinding of the K048 with SMD studies showed that the active pyridinium ring of the drug undergoes a complete turn along the gorge axis and is directed away from the phosphorus atom conjugated to the active serine of the tabun-mutant mAChE(Y337A). Such effects inside the gorge of tabun-mutant mAChE(Y337A) would lower the efficacy of the drug molecule (K048

  9. Anticancer drugs induce hypomethylation of the acetylcholinesterase promoter via a phosphorylated-p38-DNMT1-AChE pathway in apoptotic hepatocellular carcinoma cells.

    PubMed

    Xi, Qiliang; Gao, Ning; Yang, Yang; Ye, Weiyuan; Zhang, Bo; Wu, Jun; Jiang, Gening; Zhang, Xuejun

    2015-11-01

    Apoptosis, also known as programmed cell death, plays an essential role in eliminating excessive, damaged or harmful cells. Previous work has demonstrated that anticancer drugs induce cell apoptosis by inducing cytotoxicity. In recent years, several reports demonstrated modulated expression of DNA methyltransferases 1 (DNMT1) and acetylcholinesterase (AChE) in a variety of tumors. In this study, we showed that the expression of DNMT1 was decreased and the methylation of CpGs in the promoter of AChE was reduced in anticancer drugs-induced apoptotic hepatocellular carcinoma cells. Silencing of DNMT1 expression by AZA or RNA interference (RNAi) restored AChE production and inhibition of AChE expression by RNAi protected HCC cells from anticancer drugs-induced apoptosis. Furthermore, we demonstrated that the regulation of AChE by DNMT1 was involved in the phosphorylated p38 pathway in anticancer drugs-induced apoptosis. In addition, immunohistochemical staining showed that P-p38, DNMT1 and AChE were aberrantly expressed in a subset of HCC tumors. Taken together, we demonstrated the regulation of AChE by DNMT1 and further, we found that this regulation was involved in the phosphorylated p38 pathway in anticancer drugs-induced apoptosis.

  10. Effects of intralipid and caffeic acid phenethyl ester on neurotoxicity, oxidative stress, and acetylcholinesterase activity in acute chlorpyriphos intoxication

    PubMed Central

    Ozkan, Umit; Osun, Arif; Basarslan, Kagan; Senol, Serkan; Kaplan, Ibrahim; Alp, Harun

    2014-01-01

    Chlorpyriphos is one of the most widely used organophosphate (OP) insecticide in agriculture with potential toxicity. Current post-exposure treatments consist of anti-cholinergic drugs and oxime compounds. We studied the effects of intralipid and caffeic acid phenethyl ester (CAPE) on chlorpyriphos toxicity to compose an alternative or supportive treatment for OP poisoning. Methods: Forty-nine rats were randomly divided into seven groups. Chlorpyriphos was administered for toxicity. Intralipid (IL) and CAPE administered immediately after chlorpyriphos. Serum acetylcholinesterase (AChE) level, total oxidant status (TOS), total antioxidant response (TAR), and histologic examination of cerebellum and brain tissue with Hematoxylin-Eosin and immunohistochemical dyes were examined. Results: Serum enzym levels showed that chlorpyriphos and CAPE inhibited AChE while IL alone had no effect, chlorpyriphos and CAPE intensifies the inhibition effect. Significant difference at AChE levels between the chlorpyriphos+IL and chlorpyriphos+CAPE verified that IL has a protective effect on AChE inhibition. TAR levels were significantly increased in all groups except chlorpyriphos group, TOS levels revealed that CAPE and IL decrease the amount of oxidative stress. Histologic examination revealed that neuronal degeneration was slightly decreased at chlorpyriphos+IL group, but CAPE had a significant effect on protection of neuronal degeneration. Conclusion: The results of this study gave us three key points. 1) AChE activity is important for diagnosis of OP intoxication but it has no value for determining the neuro-degeneration. 2) CAPE inhibits AChE activity and may increase the muscarinic-nicotinic hyperactivation. Therefore it should not be used for treatment of OP intoxication. 3) IL decreases the severity of neurodegeneration and symptoms of OP intoxication and it can be used as a supportive agent. PMID:24955152

  11. Structure-activity relationship for the reactivators of acetylcholinesterase inhibited by nerve agent VX.

    PubMed

    Kuca, Kamil; Musilek, Kamil; Jun, Daniel; Karasova, Jana; Soukup, Ondrej; Pejchal, Jaroslav; Hrabinova, Martina

    2013-08-01

    Nerve agents such as sarin, VX and tabun are organophosphorus compounds able to inhibit an enzyme acetylcholinesterase (AChE). AChE reactivators and anticholinergics are generally used as antidotes in the case of intoxication with these agents. None from the known AChE reactivators is able to reactivate AChE inhibited by all kinds of nerve agents. In this work, reactivation potency of seventeen structurally different AChE reactivators was tested in vitro and subsequently, relationship between their chemical structure and biological activity was outlined. VX was chosen as appropriate member of the nerve agent family.

  12. Reactivation of organophosphate-inhibited human AChE by combinations of obidoxime and HI 6 in vitro.

    PubMed

    Worek, F; Aurbek, N; Thiermann, H

    2007-01-01

    Highly toxic organophosphorus-type (OP) chemical warfare agents (nerve agents) and OP pesticides may be used by terrorists and during military conflicts emphasizing the necessity for the development of effective medical countermeasures. The standard treatment with atropine and acetylcholinesterase (AChE) reactivators (oximes) is considered to be ineffective with certain nerve agents due to low oxime efficacy. Despite research over decades none of the oximes has turned out to be a broad spectrum reactivator to cover the whole range of potential threat agents. The prospective oxime HI 6 is a weak reactivator of tabun- and pesticide-inhibited AChE, while the established oxime obidoxime mainly lacks efficacy with cyclosarin-inhibited enzyme. In order to investigate the feasibility of combining obidoxime and HI 6, human AChE inhibited by sarin, cyclosarin, VX, tabun and paraoxon was reactivated by these oximes either alone or in combination. Two major findings of this study were that a combination of HI 6 and obidoxime did not impair reactivation, compared with HI 6 or obidoxime alone, but broadened the spectrum compared with the individual oximes. By using different oxime concentrations a combination of oxime doses may be suggested which could be an alternative to individual obidoxime or HI 6 autoinjectors.

  13. The Older Woman: Increased Psychosocial Benefits from Physical Activity.

    ERIC Educational Resources Information Center

    Wakat, Diane; Odom, Sarah

    1982-01-01

    Older women who participate in physical activity programs find physical benefits in the improvement of cardiovascular and musculoskeletal systems. The psychosocial benefits which result from physical activity include an increase in self-esteem, increased social contacts, a counteraction to depression, and improved stress management. Suggestions…

  14. The role of the laterodorsal tegmental nucleus in methamphetamine conditioned place preference and locomotor activity.

    PubMed

    Dobbs, Lauren K; Cunningham, Christopher L

    2014-05-15

    Methamphetamine (METH) indirectly stimulates the laterodorsal tegmental nucleus (LDT) acetylcholine (ACh) neurons to increase ACh within the ventral tegmental area (VTA). LDT ACh inhibition attenuates METH and saline locomotor activity. The aim of these experiments was to determine whether LDT ACh contributes to METH conditioned place preference (CPP). C57BL/6J mice received a bilateral electrolytic or sham lesion of the LDT. After recovery, mice received alternating pairings of METH (0.5 mg/kg) and saline with distinct tactile floor cues over 8 days. During preference tests, mice were given access to both floor types and time spent on each was recorded. Mice were tested again after exposure to both extinction and reconditioning trials. Brains were then processed for choline acetyltransferase immunohistochemistry to label LDT ACh neurons. Lesioned mice had significantly fewer LDT ACh neurons and showed increased saline and METH locomotor activity during the first conditioning trial compared to sham mice. Locomotor activity (saline and METH) was negatively correlated with the number of LDT ACh neurons. Lesioned and sham mice showed similar METH CPP following conditioning, extinction and reconditioning trials. LDT ACh neurons are not necessary for METH reward as indexed by CPP, but may be important for basal and METH-induced locomotor activity.

  15. Best Practices and Recommendations for Increasing Physical Activity in Youth

    ERIC Educational Resources Information Center

    Erwin, Heather; Beets, Michael W.; Centeio, Erin; Morrow, James R., Jr.

    2014-01-01

    Many efforts to increase the physical activity levels of Americans have been introduced and implemented over the past 20 years. National Physical Activity Guidelines have been established, and the National Physical Activity Plan (NPAP) is now in place, which includes a specific sector dedicated to education. This article addresses the Education…

  16. School-Based Health Promotion Initiative Increases Children's Physical Activity

    ERIC Educational Resources Information Center

    Cluss, Patricia; Lorigan, Devin; Kinsky, Suzanne; Nikolajski, Cara; McDermott, Anne; Bhat, Kiran B.

    2016-01-01

    Background: Childhood obesity increases health risk, and modest physical activity can impact that risk. Schools have an opportunity to help children become more active. Purpose: This study implemented a program offering extra school-day activity opportunities in a rural school district where 37% of students were obese or overweight in 2005 and…

  17. Activation of α7 nicotinic receptors by orthosteric and allosteric agonists: influence on single-channel kinetics and conductance.

    PubMed

    Pałczyńska, Magda M; Jindrichova, Marie; Gibb, Alasdair J; Millar, Neil S

    2012-11-01

    Nicotinic acetylcholine receptors (nAChRs) are oligomeric transmembrane proteins in which five subunits coassemble to form a central ion channel pore. Conventional agonists, such as acetylcholine (ACh), bind to an orthosteric site, located at subunit interfaces in the extracellular domain. More recently, it has been demonstrated that nAChRs can also be activated by ligands binding to an allosteric transmembrane site. In the case of α7 nAChRs, ACh causes rapid activation and almost complete desensitization. In contrast, allosteric agonists such as 4-(4-bromophenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c] quin oline-8-sulfonamide (4BP-TQS) activate α7 nAChRs more slowly and cause only low levels of apparent desensitization. In the present study, single-channel patch-clamp recording has been used to investigate differences in the mechanism of activation of α7 nAChRs by ACh and 4BP-TQS. The most striking difference between activation by ACh and 4BP-TQS is in single-channel kinetics. In comparison with activation by ACh, single-channel open times and burst lengths are substantially longer (~160-800-fold, respectively), and shut times are shorter (~8-fold) when activated by 4BP-TQS. In addition, coapplication of ACh and 4BP-TQS results in a further increase in single-channel burst lengths. Mean burst lengths seen when the two agonists are coapplied (3099 ± 754 ms) are ~2.5-fold longer than with 4BP-TQS alone and ∼370-fold longer than with ACh alone. Intriguingly, the main single-channel conductance of α7 nAChRs, was significantly larger when activated by 4BP-TQS (100.3 ± 2.4 pS) than when activated by ACh (90.0 ± 2.7 pS), providing evidence that activation by allosteric and orthosteric agonists results in different α7 nAChRs open-channel conformations.

  18. Activation of α7 Nicotinic Receptors by Orthosteric and Allosteric Agonists: Influence on Single-Channel Kinetics and Conductance

    PubMed Central

    Pałczyńska, Magda M.; Jindrichova, Marie; Gibb, Alasdair J.

    2012-01-01

    Nicotinic acetylcholine receptors (nAChRs) are oligomeric transmembrane proteins in which five subunits coassemble to form a central ion channel pore. Conventional agonists, such as acetylcholine (ACh), bind to an orthosteric site, located at subunit interfaces in the extracellular domain. More recently, it has been demonstrated that nAChRs can also be activated by ligands binding to an allosteric transmembrane site. In the case of α7 nAChRs, ACh causes rapid activation and almost complete desensitization. In contrast, allosteric agonists such as 4-(4-bromophenyl)-3a,4,5,9b-tetrahydro-3H-cyclopenta[c] quin oline-8-sulfonamide (4BP-TQS) activate α7 nAChRs more slowly and cause only low levels of apparent desensitization. In the present study, single-channel patch-clamp recording has been used to investigate differences in the mechanism of activation of α7 nAChRs by ACh and 4BP-TQS. The most striking difference between activation by ACh and 4BP-TQS is in single-channel kinetics. In comparison with activation by ACh, single-channel open times and burst lengths are substantially longer (∼160–800-fold, respectively), and shut times are shorter (∼8-fold) when activated by 4BP-TQS. In addition, coapplication of ACh and 4BP-TQS results in a further increase in single-channel burst lengths. Mean burst lengths seen when the two agonists are coapplied (3099 ± 754 ms) are ∼2.5-fold longer than with 4BP-TQS alone and ∼370-fold longer than with ACh alone. Intriguingly, the main single-channel conductance of α7 nAChRs, was significantly larger when activated by 4BP-TQS (100.3 ± 2.4 pS) than when activated by ACh (90.0 ± 2.7 pS), providing evidence that activation by allosteric and orthosteric agonists results in different α7 nAChRs open-channel conformations. PMID:22874415

  19. ACH-806, an NS4A antagonist, inhibits hepatitis C virus replication by altering the composition of viral replication complexes.

    PubMed

    Yang, Wengang; Sun, Yongnian; Hou, Xiaohong; Zhao, Yongsen; Fabrycki, Joanne; Chen, Dawei; Wang, Xiangzhu; Agarwal, Atul; Phadke, Avinash; Deshpande, Milind; Huang, Mingjun

    2013-07-01

    Treatment of hepatitis C patients with direct-acting antiviral drugs involves the combination of multiple small-molecule inhibitors of distinctive mechanisms of action. ACH-806 (or GS-9132) is a novel, small-molecule inhibitor specific for hepatitis C virus (HCV). It inhibits viral RNA replication in HCV replicon cells and was active in genotype 1 HCV-infected patients in a proof-of-concept clinical trial (1). Here, we describe a potential mechanism of action (MoA) wherein ACH-806 alters viral replication complex (RC) composition and function. We found that ACH-806 did not affect HCV polyprotein translation and processing, the early events of the formation of HCV RC. Instead, ACH-806 triggered the formation of a homodimeric form of NS4A with a size of 14 kDa (p14) both in replicon cells and in Huh-7 cells where NS4A was expressed alone. p14 production was negatively regulated by NS3, and its appearance in turn was associated with reductions in NS3 and, especially, NS4A content in RCs due to their accelerated degradation. A previously described resistance substitution near the N terminus of NS3, where NS3 interacts with NS4A, attenuated the reduction of NS3 and NS4A conferred by ACH-806 treatment. Taken together, we show that the compositional changes in viral RCs are associated with the antiviral activity of ACH-806. Small molecules, including ACH-806, with this novel MoA hold promise for further development and provide unique tools for clarifying the functions of NS4A in HCV replication.

  20. Phytoestrogens genistein and daidzin enhance the acetylcholinesterase activity of the rat pheochromocytoma cell line PC12 by binding to the estrogen receptor.

    PubMed

    Isoda, Hiroko; Talorete, Terence P N; Kimura, Momoko; Maekawa, Takaaki; Inamori, Yuhei; Nakajima, Nobuyoshi; Seki, Humitake

    2002-11-01

    Some compounds derived from plants have been known to possess estrogenic properties and can thus alter the physiology of higher organisms. Genistein and daidzin are examples of these phytoestrogens, which have recently been the subject of extensive research. In this study, genistein and daidzin were found to enhance the acetylcholinesterase (AChE) activity of the rat neuronal cell line PC12 at concentrations as low as 0.08 muM by binding to the estrogen receptor (ER). Results have shown that this enhancement was effectively blocked by the known estrogen receptor antagonist tamoxifen, indicating the involvement of the ER in AChE induction. That genistein and daidzin are estrogenic were confirmed in a cell proliferation assay using the human breast cancer cell line MCF7. This proliferation was also blocked by tamoxifen, again indicating the involvement of the ER. On the other hand, incubating the PC12 cells in increasing concentrations of 17 beta-estradiol (E2) did not lead to enhanced AChE activity, even in the presence of genistein or daidzin. This suggests that mere binding of an estrogenic compound to the ER does not necessarily lead to enhanced AChE activity. Moreover, the effect of the phytoestrogens on AChE activity cannot be expressed in the presence of E2 since they either could not compete with the natural ligand in binding to the ER or that E2 down-regulates its own receptor. This study clearly suggests that genistein and daidzin enhance AChE activityin PC12 cells by binding to the ER; however, the actual mechanism of enhancement is not known.

  1. Agonists with supraphysiological efficacy at the muscarinic M2 ACh receptor

    PubMed Central

    Schrage, R; Seemann, WK; Klöckner, J; Dallanoce, C; Racké, K; Kostenis, E; De Amici, M; Holzgrabe, U; Mohr, K

    2013-01-01

    Background and Purpose Artificial agonists may have higher efficacy for receptor activation than the physiological agonist. Until now, such ‘superagonism’ has rarely been reported for GPCRs. Iperoxo is an extremely potent muscarinic receptor agonist. We hypothesized that iperoxo is a ‘superagonist’. Experimental Approach Signalling of iperoxo and newly synthesized structural analogues was compared with that of ACh at label-free M2 muscarinic receptors applying whole cell dynamic mass redistribution, measurement of G-protein activation, evaluation of cell surface agonist binding and computation of operational efficacies. Key Results In CHO-hM2 cells, iperoxo significantly exceeds ACh in Gi/Gs signalling competence. In the orthosteric loss-of-function mutant M2-Y1043.33A, the maximum effect of iperoxo is hardly compromised in contrast to ACh. ‘Superagonism’ is preserved in the physiological cellular context of MRC-5 human lung fibroblasts. Structure–signalling relationships including iperoxo derivatives with either modified positively charged head group or altered tail suggest that ‘superagonism’ of iperoxo is mechanistically based on parallel activation of the receptor protein via two orthosteric interaction points. Conclusion and Implications Supraphysiological agonist efficacy at muscarinic M2 ACh receptors is demonstrated for the first time. In addition, a possible underlying molecular mechanism of GPCR ‘superagonism’ is provided. We suggest that iperoxo-like orthosteric GPCR activation is a new avenue towards a novel class of receptor activators. Linked Article This article is commented on by Langmead and Christopoulos, pp. 353–356 of this issue. To view this commentary visit http://dx.doi.org/10.1111/bph.12142 PMID:23062057

  2. THE ACHES THAT TAKE YOUR BREATH (AND TEARS) AWAY.

    PubMed

    Becerril, J; Gonzales, H; Saketkoo, L A

    2015-01-01

    An 80-year-old man presented with a complaint of three months of fatigue and aching of his shoulders and hips, as well as pain, swelling, and stiffness in bilateral fingers that was worse in the morning but improved with movement. Associated symptoms included worsening dry mouth and eyes, dysphagia, exertional dyspnea, and right foot drop. Physical exam was significant for edematous and tender bilateral proximal interphalangeal joints, metacarpophalangeal joints and wrists with decreased grip, extension and flexion, as well as bilateral pulmonary crackles. Laboratory analysis revealed Anti-Ro (SSA) and Anti-La (SSB) positivity with elevated erythrocyte sedimentation rate (70mm/hr) and C-reactive peptide (13mg/L). Pulmonary function testing was notable for a forced vital capacity (FVC) of 64% and carbon monoxide diffusing capacity (DLCO) of 44%. High resolution chest computed tomography demonstrated fibrotic changes consistent with nonspecific interstitial pneumonitis. The patient was started on mycophenolate mofetil, hydroxychloroquine, and prednisone for Sjögren's syndrome (SjS). Symptoms improved and repeat FVC revealed a 20 percent improvement, however subsequent tapering of prednisone resulted in worsening dyspnea and increase of FVC to 60 prcent. Prednisone was restarted and rituximab 2g divided in two doses was administered with overall symptom improvement. Symptoms and FVC continued to wax and wane over the following 18 months requiring re-dosing of rituximab with most recent FVC improved to 71 percent and DLCO 41 percent.

  3. Effect of pesticide exposure on acetylcholinesterase activity in subsistence farmers from Campeche, Mexico.

    PubMed

    Rendón von Osten, Jaime; Epomex, Centro; Tinoco-Ojanguren, Rolando; Soares, Amadeu M V M; Guilhermino, Lucia

    2004-08-01

    The authors surveyed agricultural production methods and pesticide use among subsistence farmers (campesinos) in 4 rural communities of Campeche, Mexico. Self-reports of symptoms of poisoning resulting from occupational pesticide exposure were elicited by questionnaire (N = 121), and acetylcholinesterase (AChE) activity during insecticide use was evaluated from blood samples (N = 127). In individuals from 2 of the 4 communities, AChE activity was significantly lower (p < 0.05) than the mean of activity determined for individuals in a reference group. Results of this study show that erythrocyte AChE inhibition provides a good biomarker of exposure to organophosphate pesticides in field studies with human populations. Carbamates, particularly carbofuran, seem to be more associated with exuberant and diversified symptomatology of pesticide exposure than organophosphates. Studies in field communities where both carbamates and organophosphates are suspected to exist should include blood AChE determinations, symptomatology surveys, and socioeconomic questionnaires. The authors recommend that the Mexican National Health Ministry authorities specify additional provisions regarding the use of protective equipment and the adoption of other safety practices during field work, increase information campaigns about the risks of pesticide use and the value of safety practices, and increase programs of medical monitoring and assistance for rural communities dealing with pesticides.

  4. Acetylcholinesterase inhibitory activity of Thai traditional nootropic remedy and its herbal ingredients.

    PubMed

    Tappayuthpijarn, Pimolvan; Itharat, Arunporn; Makchuchit, Sunita

    2011-12-01

    The incidence of Alzheimer disease (AD) is increasing every year in accordance with the increasing of elderly population and could pose significant health problems in the future. The use of medicinal plants as an alternative prevention or even for a possible treatment of the AD is, therefore, becoming an interesting research issue. Acetylcholinesterase (AChE) inhibitors are well-known drugs commonly used in the treatment of AD. The aim of the present study was to screen for AChE inhibitory activity of the Thai traditional nootropic recipe and its herbal ingredients. The results showed that ethanolic extracts of four out of twenty-five herbs i.e. Stephania pierrei Diels. Kaempfera parviflora Wall. ex Baker, Stephania venosa (Blume) Spreng, Piper nigrum L at 0.1 mg/mL showed % AChE inhibition of 89, 64, 59, 50; the IC50 were 6, 21, 29, 30 microg/mL respectively. The other herbs as well as combination of the whole recipe had no synergistic inhibitory effect on AChE activity. However some plants revealed antioxidant activity. More research should have be performed on this local wisdom remedy to verify the uses in scientific term.

  5. Technology to promote and increase physical activity in heart failure.

    PubMed

    Franklin, Nina C

    2015-01-01

    Regular physical activity is firmly recommended as part of a multifaceted approach to heart failure (HF) self-management. Unfortunately, research indicates that most patients are less likely to engage in and adhere to such activities. The widespread use of information and communication technology tools and resources offers an innovative and potentially beneficial avenue for increasing physical activity levels in HF patients. This article presents specific ways in which advances in information and communication technologies, including Internet- and mobile-based communications, social media platforms, and self-monitoring health devices, can serve as a means to broadly promote increasing levels of physical activity to improve health outcomes in the HF population.

  6. Effects of Total Ginsenosides on the Feeding Behavior and Two Enzymes Activities of Mythimna separata (Walker) Larvae

    PubMed Central

    Zhang, Ai-Hua; Tan, Shi-Qiang; Zhao, Yan; Lei, Feng-Jie; Zhang, Lian-Xue

    2015-01-01

    Ginsenosides, the main effective components of Panax ginseng C.A. Meyer and Panax quinquefolius L., are important allelochemicals of ginseng. Although many studies have targeted the pharmacological, chemical, and clinical properties of ginsenosides, little is known about their ecological role in ginseng population adaptation and evolution. Pests rarely feed on ginseng, and it is not known why. This study investigated the effects of total ginsenosides on feeding behavior and activities of acetylcholinesterase (AChE) and glutathione s-transferase (GST) in Mythimna separata (Walker) larvae. The results showed that the total ginsenosides had significant antifeeding activity against M. separata larvae, determined by nonselective and selective antifeeding bioassays. In addition, the total ginsenosides had inhibitory effects on the activities of GST and AChE. The antifeeding ratio was the highest at 8 h, then decreased, and was the lowest at 16 h. Both GST and AChE activities decreased from 0 h to 48 h in all total ginsenosides treatments but increased at 72 h. Total ginsenosides had antifeeding activity against M. separata larvae and inhibitory effects on the activities of GST and AChE. PMID:26074991

  7. Deposition of a-C:H films on a nanotrench pattern by bipolar PBII&D

    NASA Astrophysics Data System (ADS)

    Hirata, Yuki; Nakahara, Yuya; Nagato, Keisuke; Choi, Junho

    2016-06-01

    In this study, hydrogenated amorphous carbon (a-C:H) films were deposited on a nanotrench pattern (300 nm pitch, aspect ratio: 2.0) by bipolar-type plasma based ion implantation and deposition technique (bipolar PBII&D), and the effects of bipolar pulse on the film properties were investigated. Moreover, the behaviour of ions and radicals surrounding the nanotrench was analyzed to clarify the coating mechanism and properties of the a-C:H films on the nanotrench. Further, thermal nanoimprint lithography was carried out using the nanotrench pattern coated with a-C:H films as the mold, and the mold release properties were evaluated. All nanotrench surfaces were successfully coated with the a-C:H films, but the film thickness on the top, sidewall, and bottom surfaces of the trench were not uniform. The surface roughness of the a-C:H films was found to decrease at a higher positive voltage; this happens due to the higher electron temperature around the nanotrench because of the surface migration of plasma particles arrived on the trench. The effects of the negative voltage on the behaviour of ions and radicals near the sidewall of the nanotrench are quite similar to those near the microtrench reported previously (Park et al 2014 J. Phys. D: Appl. Phys. 47 335306). However, the positive pulse voltage was also found to affect the behaviour of ions and radicals near the sidewall surface. The incident angles of ions on the sidewall surface increased with the positive pulse voltage because the energy of incoming ions on the trench decreases with increasing positive voltage. Moreover, the incident ion flux on the sidewall is affected by the positive voltage history. Further, the radical flux decreases with increasing positive voltage. It can be concluded that a higher positive voltage at a lower negative voltage condition is good to obtain better film properties and higher film thickness on the sidewall surface. Pattern transfer properties for the nanoimprint formed by

  8. Asbestos exposure increases human bronchial epithelial cell fibrinolytic activity.

    PubMed

    Gross, T J; Cobb, S M; Gruenert, D C; Peterson, M W

    1993-03-01

    Chronic exposure to asbestos fibers results in fibrotic lung disease. The distal pulmonary epithelium is an early target of asbestos-mediated injury. Local plasmin activity may be important in modulating endoluminal inflammatory responses in the lung. We studied the effects of asbestos exposure on cell-mediated plasma clot lysis as a marker of pericellular plasminogen activation. Exposing human bronchial epithelial (HBE) cells to 100 micrograms/ml of asbestos fibers for 24 h resulted in increased plasma clot lysis. Fibrinolytic activity was augmented in a dose-dependent fashion, was not due to secreted protease, and occurred only when there was direct contact between the plasma clot and the epithelial monolayer. Further analysis showed that asbestos exposure increased HBE cell-associated urokinase-type plasminogen activator (uPA) activity in a time-dependent manner. The increased cell-associated PA activity could be removed by acid washing. The increase in PA activity following asbestos exposure required new protein synthesis because it was abrogated by treatment with either cycloheximide or actinomycin D. Therefore, asbestos exposure increases epithelial-mediated fibrinolysis by augmenting expression of uPA activity at the cell surface by mechanisms that require new RNA and protein synthesis. These observations suggest a novel mechanism whereby exposure of the distal epithelium to inhaled particulates may result in a chronic inflammatory response that culminates in the development of fibrotic lung disease.

  9. Increased sternocleidomastoid, but not trapezius, muscle activity in response to increased chewing load.

    PubMed

    Häggman-Henrikson, Birgitta; Nordh, Erik; Eriksson, Per-Olof

    2013-10-01

    Previous findings, during chewing, that boluses of larger size and harder texture result in larger amplitudes of both mandibular and head-neck movements suggest a relationship between increased chewing load and incremental recruitment of jaw and neck muscles. The present report evaluated jaw (masseter and digastric) and neck [sternocleidomastoid (SCM) and trapezius] muscle activity during the chewing of test foods of different sizes and textures by 10 healthy subjects. Muscle activity was recorded by surface electromyography and simultaneous mandibular and head movements were recorded using an optoelectronic technique. Each subject performed continuous jaw-opening/jaw-closing movements whilst chewing small and large boluses of chewing gum and rubber silicone (Optosil). For jaw opening/jaw closing without a bolus, SCM activity was recorded for jaw opening concomitantly with digastric activity. During chewing, SCM activity was recorded for jaw closing concomitantly with masseter activity. Trapezius activity was present in some, but not all, cycles. For the masseter and SCM muscles, higher activity was seen with larger test foods, suggesting increased demand and recruitment of these muscles in response to an increased chewing load. This result reinforces the previous notion of a close functional connection between the jaw and the neck motor systems in jaw actions and has scientific and clinical significance for studying jaw function and dysfunction.

  10. Increased olfactory bulb acetylcholine bi-directionally modulates glomerular odor sensitivity

    PubMed Central

    Bendahmane, Mounir; Ogg, M. Cameron; Ennis, Matthew; Fletcher, Max L.

    2016-01-01

    The glomerular layer of the olfactory bulb (OB) receives heavy cholinergic input from the horizontal limb of the diagonal band of Broca (HDB) and expresses both muscarinic and nicotinic acetylcholine (ACh) receptors. However, the effects of ACh on OB glomerular odor responses remain unknown. Using calcium imaging in transgenic mice expressing the calcium indicator GCaMP2 in the mitral/tufted cells, we investigated the effect of ACh on the glomerular responses to increasing odor concentrations. Using HDB electrical stimulation and in vivo pharmacology, we find that increased OB ACh leads to dynamic, activity-dependent bi-directional modulation of glomerular odor response due to the combinatorial effects of both muscarinic and nicotinic activation. Using pharmacological manipulation to reveal the individual receptor type contributions, we find that m2 muscarinic receptor activation increases glomerular sensitivity to weak odor input whereas nicotinic receptor activation decreases sensitivity to strong input. Overall, we found that ACh in the OB increases glomerular sensitivity to odors and decreases activation thresholds. This effect, along with the decreased responses to strong odor input, reduces the response intensity range of individual glomeruli to increasing concentration making them more similar across the entire concentration range. As a result, odor representations are more similar as concentration increases. PMID:27165547

  11. Mechanism of pyruvate dehydrogenase activation by increased cardiac work.

    PubMed

    Kobayashi, K; Neely, J R

    1983-06-01

    The effects of increased cardiac work, pyruvate and insulin on the state of pyruvate dehydrogenase (PDH) activation and rate of pyruvate decarboxylation was studied in the isolated perfused rat heart. At low levels of cardiac work, 61% of PDH was present in the active form when glucose was the only substrate provided. The actual rate of pyruvate decarboxylation was only 5% of the available capacity calculated from the percent of active PDH. Under this condition, the rate of pyruvate decarboxylation was restricted by the slow rate of pyruvate production from glycolysis. Increasing cardiac work accelerated glycolysis, but production of pyruvate remained rate limiting for pyruvate oxidation and only 40% of the maximal active PDH capacity was used. Addition of insulin along with glucose reduced the percent of active PDH to 16% of the total at low cardiac work. This effect of insulin was associated with increased mitochondria NADH/NAD and acetyl CoA/CoA ratios. With both glucose and insulin the calculated maximum capacity of active PDH was about the same as measured rates of pyruvate oxidation indicating that pyruvate oxidation was limited by the activation state of PDH. In this case, raising the level of cardiac work increased the active PDH to 85% and although pyruvate oxidation was accelerated, measured flux through PDH was only 73% of the maximal activity of active PDH. With pyruvate as added exogenous substrate, PDH was 82% of active at low cardiac work probably due to pyruvate inhibition of PDH kinase. In this case, the measured rate of pyruvate oxidation was 64% of the capacity of active PDH. However, increased cardiac work still caused further activation of PDH to 96% active. Thus, actual rates of pyruvate oxidation in the intact tissue were determined by (1) the supply of pyruvate in hearts receiving glucose alone, (2) by the percent of active PDH in hearts receiving both glucose and insulin at low work and (3) by end-product inhibition in hearts receiving

  12. Activation of the α7 nicotinic receptor promotes lipopolysaccharide-induced conversion of M1 microglia to M2

    PubMed Central

    Zhang, Qichun; Lu, Ying; Bian, Huimin; Guo, Liwei; Zhu, Huaxu

    2017-01-01

    The α7 subtype of the nicotinic acetylcholine receptor (α7 nAChR) plays an essential role in the cholinergic anti-inflammatory pathway that regulates macrophage/microglia function in inflammation. Similar to M1 and M2 macrophages, M1 and M2 microglia exhibit pro-inflammation and anti-inflammation properties, respectively. In the present study, we analyzed function-associated phenotypes to detect the transformation of microglia with activation of α7 nAChRs. We used lentivirus-mediated shRNA to knockdown the expression of α7 nAChR in BV-2 microglia incubated with lipopolysaccharides (LPS, 0.1 μg/mL) and measured the acetylcholine (Ach, 1 μg/mL)-mediated release of cytokines, such as IL-1β, IL-4, IL-6, and IL-10, in the culture supernatant via radioimmunoassay. After stimulation with Ach, the expression of typical biomarkers for different microglia phenotypes, Iba-1 and Arg-1, was determined by cellular immunofluorescence. Furthermore, the expression of signaling molecules, including p38, JAK2/STAT3, PI3K/Akt and miR-124, was analyzed via western blotting and real-time PCR. We found that Ach inhibited LPS-induced IL-1β and IL-6 elevation and promoted IL-4 and IL-10 production and that knockdown of the α7 nAChR abolished these effects of Ach. In addition, Ach decreased LPS-induced Iba-1 expression and increased Arg-1 levels in an α7 nAChR-dependent manner. The LPS-inhibited activation of JAK2/STAT3 and PI3K/Akt was also rescued by Ach, an effect that was blocked by knockdown of the α7 nAChR. In contrast, Ach triggered the phosphorylation of JAK2 and STAT3 that was otherwise inactivated by LPS in BV-2 cells. Finally, the levels of miR-124 and downstream targets C/EBPα and PU.1 were significantly enhanced in LPS-treated BV-2 microglia, and the effect of Ach on this signaling pathway was blocked by α7 nAChR knockdown as expected. Overall, our data demonstrate that activation ofα7 nAChRs inhibits the transformation of M1 microglia and promotes the M2

  13. Effect of a glyphosate-based herbicide in Cyprinus carpio: assessment of acetylcholinesterase activity, hematological responses and serum biochemical parameters.

    PubMed

    Gholami-Seyedkolaei, Seyed Jalil; Mirvaghefi, Alireza; Farahmand, Hamid; Kosari, Ali Asghar

    2013-12-01

    The objective of this study was to investigate the toxicity effects of acute and sublethal of Roundup® as a glyphosate-based herbicide on acetylcholinesterase (AChE) activity and several hematological and biochemical parameters of Cyprinus carpio. The LC₅₀-96 h of Roundup® to C. carpio was found to be 22.19 ppm. Common carp was subjected to Roundup® at 0 (control), 3.5, 7 and 14 ppm for 16 days, and the AChE activity is verified in tissues of gill, muscle, brain and liver. After 5 days, a significant decrease was observed in the AChE activity of muscle, brain and liver tissues. Besides, a time- and dose-dependent increase in mean cell hemoglobin (MCH) and mean cell volume (MCV) was observed. In contrast, a significant decrease was found in the quantities of hemoglobin (Hb), hematocrit (HCT) and, red (RBC) and white (WBC) blood cell count. Also, the activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) in Roundup® treated groups were significantly higher than the controlled group at experimental periods. However, the level of alkaline phosphatase (ALP) had a significant reduction behavior during the sampling days. It seems that the changes in hematological and biochemical parameters as well as AChE activity could be used as efficient biomarkers in order to determine Roundup® toxicity in aquatic environment.

  14. Building a better mousetrap (exergame) to increase youth physical activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While exergames have been demonstrated to induce moderate levels of physical activity (PA) if played as designed, there is conflicting evidence on use of exergaming leading to increased habitual PA. Exergames have increased PA in some home and school studies, but not others. Exergames have been us...

  15. Efficient Expression of Functional (α6β2)2β3 AChRs in Xenopus Oocytes from Free Subunits Using Slightly Modified α6 Subunits

    PubMed Central

    Ley, Carson Kai-Kwong; Kuryatov, Alexander; Wang, Jingyi; Lindstrom, Jon Martin

    2014-01-01

    Human (α6β2)(α4β2)β3 nicotinic acetylcholine receptors (AChRs) are essential for addiction to nicotine and a target for drug development for smoking cessation. Expressing this complex AChR is difficult, but has been achieved using subunit concatamers. In order to determine what limits expression of α6* AChRs and to efficiently express α6* AChRs using free subunits, we investigated expression of the simpler (α6β2)2β3 AChR. The concatameric form of this AChR assembles well, but is transported to the cell surface inefficiently. Various chimeras of α6 with the closely related α3 subunit increased expression efficiency with free subunits and produced pharmacologically equivalent functional AChRs. A chimera in which the large cytoplasmic domain of α6 was replaced with that of α3 increased assembly with β2 subunits and transport of AChRs to the oocyte surface. Another chimera replacing the unique methionine 211 of α6 with leucine found at this position in transmembrane domain 1 of α3 and other α subunits increased assembly of mature subunits containing β3 subunits within oocytes. Combining both α3 sequences in an α6 chimera increased expression of functional (α6β2)2β3 AChRs to 12-fold more than with concatamers. This is pragmatically useful, and provides insights on features of α6 subunit structure that limit its expression in transfected cells. PMID:25068303

  16. Efficient expression of functional (α6β2)2β3 AChRs in Xenopus oocytes from free subunits using slightly modified α6 subunits.

    PubMed

    Ley, Carson Kai-Kwong; Kuryatov, Alexander; Wang, Jingyi; Lindstrom, Jon Martin

    2014-01-01

    Human (α6β2)(α4β2)β3 nicotinic acetylcholine receptors (AChRs) are essential for addiction to nicotine and a target for drug development for smoking cessation. Expressing this complex AChR is difficult, but has been achieved using subunit concatamers. In order to determine what limits expression of α6* AChRs and to efficiently express α6* AChRs using free subunits, we investigated expression of the simpler (α6β2)2β3 AChR. The concatameric form of this AChR assembles well, but is transported to the cell surface inefficiently. Various chimeras of α6 with the closely related α3 subunit increased expression efficiency with free subunits and produced pharmacologically equivalent functional AChRs. A chimera in which the large cytoplasmic domain of α6 was replaced with that of α3 increased assembly with β2 subunits and transport of AChRs to the oocyte surface. Another chimera replacing the unique methionine 211 of α6 with leucine found at this position in transmembrane domain 1 of α3 and other α subunits increased assembly of mature subunits containing β3 subunits within oocytes. Combining both α3 sequences in an α6 chimera increased expression of functional (α6β2)2β3 AChRs to 12-fold more than with concatamers. This is pragmatically useful, and provides insights on features of α6 subunit structure that limit its expression in transfected cells.

  17. Acetylcholinesterase Activity, Cohabitation with Floricultural Workers, and Blood Pressure in Ecuadorian Children

    PubMed Central

    Jacobs, David R.; Himes, John H.; Alexander, Bruce H.

    2013-01-01

    Background: Acetylcholinesterase (AChE) inhibitors are commonly used pesticides that can effect hemodynamic changes through increased cholinergic stimulation. Children of agricultural workers are likely to have paraoccupational exposures to pesticides, but the potential physiological impact of such exposures is unclear. Objectives: We investigated whether secondary pesticide exposures were associated with blood pressure and heart rate among children living in agricultural Ecuadorian communities. Methods: This cross-sectional study included 271 children 4–9 years of age [51% cohabited with one or more flower plantation workers (mean duration, 5.2 years)]. Erythrocyte AChE activity was measured using the EQM Test-mate system. Linear regression models were used to estimate associations of systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate with AChE activity, living with flower workers, duration of cohabitation with a flower worker, number of flower workers in the child’s home, and number of practices that might increase children’s exposure to pesticides. Results: Mean (± SD) AChE activity was 3.14 ± 0.49 U/mL. A 1-U/mL decrease in AChE activity was associated with a 2.86-mmHg decrease in SBP (95% CI: –5.20, –0.53) and a 2.89-mmHg decrease in DBP (95% CI: –5.00, –0.78), after adjustment for potential confounders. Children living with flower workers had lower SBP (–1.72 mmHg; 95% CI: –3.53, 0.08) than other children, and practices that might increase exposure also were associated with lower SBP. No significant associations were found between exposures and heart rate. Conclusions: Our findings suggest that subclinical secondary exposures to pesticides may affect vascular reactivity in children. Additional research is needed to confirm these findings. PMID:23359481

  18. The atypical antipsychotic olanzapine disturbs depotentiation by modulating mAChRs and impairs reversal learning.

    PubMed

    Song, Woo Seok; Cha, Jin Hee; Yoon, Sang Ho; Cho, Young Seon; Park, Kyeong-Yeol; Kim, Myoung-Hwan

    2017-03-01

    Antipsychotic medication is an essential component for treating schizophrenia, which is a serious mental disorder that affects approximately 1% of the global population. Olanzapine (Olz), one of the most frequently prescribed atypical antipsychotics, is generally considered a first-line drug for treating schizophrenia. In contrast to psychotic symptoms, the effects of Olz on cognitive symptoms of schizophrenia are still unclear. In addition, the mechanisms by which Olz affects the neural circuits associated with cognitive function are unknown. Here we show that Olz interrupts depotentiation (reversal of long-term potentiation) without disturbing de novo LTP (long-term potentiation) and LTD (long-term depression). At hippocampal SC-CA1 synapses, inhibition of NMDARs (N-methyl-d-aspartate receptors), mGluRs (metabotropic glutamate receptors), or mAChRs (muscarinic acetylcholine receptors) disrupted depotentiation. In addition, co-activation of NMDARs, mGluRs, and mAChRs reversed stably expressed LTP. Olz inhibits the activation of mAChRs, which amplifies glutamate signaling through enhanced NMDAR opening and Gq (Gq class of G protein)-mediated signal transduction. Behaviorally, Olz impairs spatial reversal learning of mice in the Morris water maze test. Our results uncover a novel mechanism underpinning the cognitive modulation of Olz and show that the anticholinergic property of Olz affects glutamate signaling and synaptic plasticity.

  19. Design, synthesis and structure-activity relationships of dual inhibitors of acetylcholinesterase and serotonin transporter as potential agents for Alzheimer's disease.

    PubMed

    Toda, Narihiro; Tago, Keiko; Marumoto, Shinji; Takami, Kazuko; Ori, Mayuko; Yamada, Naho; Koyama, Kazuo; Naruto, Shunji; Abe, Kazumi; Yamazaki, Reina; Hara, Takao; Aoyagi, Atsushi; Abe, Yasuyuki; Kaneko, Tsugio; Kogen, Hiroshi

    2003-05-01

    We have designed and synthesized a dual inhibitor of acetylcholinesterase (AChE) and serotonin transporter (SERT) as a novel class of treatment drugs for Alzheimer's disease on the basis of a hypothetical model of the AChE active site. Dual inhibitions of AChE and SERT would bring about greater therapeutic effects than AChE inhibition alone and avoid adverse peripheral effects caused by excessive AChE inhibition. Compound (S)-6j exhibited potent inhibitory activities against AChE (IC(50)=101 nM) and SERT (IC(50)=42 nM). Furthermore, (S)-6j showed inhibitory activities of both AChE and SERT in mice brain following oral administration.

  20. A combined molecular docking and charge density analysis is a new approach for medicinal research to understand drug-receptor interaction: curcumin-AChE model.

    PubMed

    Renuga Parameswari, A; Rajalakshmi, G; Kumaradhas, P

    2015-01-05

    In the present study, a molecular docking analysis has been performed on diketone form of curcumin molecule with acetylcholinesterase (AChE). The calculated lowest docked energy of curcumin molecule in the active site of AChE is -11.21 kcal/mol; this high negative value indicates that the molecule exhibits large binding affinity towards AChE. When the curcumin molecule present in the active site of AChE, subsequently, its conformation has altered significantly and the molecule adopts a U-shape geometry as it is linear in gas phase (before entering into the active site). This conformational transition facilitates curcumin to form strong interaction with Phe330 of acyl-binding pocket and the choline binding site with indole ring of Trp84 and Asp72. The gas phase and the active site analysis of curcumin allows to understand the conformational geometry, nature of molecular flexibility, charge density redistribution and the variation of electrostatic properties of curcumin in the active site. To obtain the gas phase structure, the curcumin molecule was optimized using Hartree-Fock and density functional methods (B3LYP) with the basis set 6-311G(∗∗). A charge density analysis on both gas phase as well as the molecule lifted from the active site was carried out using Bader's theory of atoms in molecules (AIM). The difference in molecular electrostatic potential between the two forms of curcumin displays the difference in charge distribution. The large dipole moment of curcumin (7.54 D) in the active site reflects the charge redistribution as it is much less in the gas phase (4.34 D).

  1. [Increase of physical activity by improvement of the nutritional status].

    PubMed

    Torún, B

    1989-09-01

    Physical activity is affected by nutritional modifications and, in turn, influences growth, cognition, social behavior, work performance and other functions. Studies in preschool children showed that: 1. A decrease in energy intake during four to seven days reduced the time allocated to energy-demanding activities and increased sedentary activities. 2. Children with mild weight deficit were more sedentary than well-nourished counterparts. 3. Children became more active when nutritional status improved. 4. A 10% reduction in energy intake reduced total energy expenditure by 15% without affecting weight gain nor basal metabolism. Studies of men working in non-mechanized agriculture showed that: 1. Dietary improvements led to faster salaried work, reduction of napping time and greater physical activity after work. 2. An increase in energy intake increased total daily energy expenditure, tending to maintain energy balance and relatively stable body weight within the cyclic variations of the agricultural year. 3. Food supplementation did not necessarily improve productivity. Other labor incentives without dietary improvements increased energy expenditure during working hours, which resulted in weight loss. In conclusion, good health and nutrition provide the biological basis for adequate physical activity that may improve cognitive development, social interactions, economic productivity and the quality of life of an individual or a population, but other incentives are required for the optimal expression of that biologic potential.

  2. Acetylcholine increases intracellular calcium of arterial chemoreceptor cells of adult cats.

    PubMed

    Shirahata, M; Fitzgerald, R S; Sham, J S

    1997-11-01

    Acetylcholine increases intracellular calcium of arterial chemoreceptor cells of adult cats. J. Neurophysiol. 78: 2388-2395, 1997. Several neurotransmitters have been reported to play important roles in the chemoreception of the carotid body. Among them acetylcholine (ACh) appears to be involved in excitatory processes in the cat carotid body. As one of the steps to elucidate possible roles of ACh in carotid body chemoreception in the cat, we examined the effect of ACh on intracellular calcium concentration ([Ca2+]i) of cultured carotid body cells. The carotid body from adult cats was dissociated and cultured for up to 2 wk. [Ca2+]i was measured from clusters of cells with a microfluorometric technique using Indo-1 AM. Experiments were performed at 37 degrees C, and cells were continuously superfused with modified Krebs solutions equilibrated with 5% CO2-16% O2-79% N2. ACh (100 mu M) caused a marked increase in [Ca2+]i in approximately 70% of clusters, and the responses to 1-300 mu M of ACh were concentration dependent. The magnitude and kinetics of the ACh response were mimicked by the application of nicotine, whereas muscarinic agonists, pilocarpine, and muscarine failed to evoke a similar response. ACh-induced increase in [Ca2+]i was dependent on extracellular Ca2+: it was greatly reduced or completely abolished by a transient removal of extracellular Ca2+. The response was consistently but only partially reduced by caffeine (5 mM) or nifedipine (10 mu M). The effect of mecamylamine (100 mu M) was inhibitory but small. Moreover, the increase in [Ca2+]i in response to ACh was also observed in some clusters that did not respond to high K (100 mM) Krebs. These results suggest that ACh increases [Ca2+]i of cultured carotid body cells by activating neuronal nicotinic ACh receptors, leading to Ca2+ influx via nicotinic channels. In addition, other pathways such as Ca2+ influx through L-type calcium channels, perhaps secondary to membrane depolarization, and Ca2

  3. Evidence for aging theories from the study of a hunter-gatherer people (Ache of Paraguay).

    PubMed

    Libertini, G

    2013-09-01

    In the late seventies, a small tribal population of Paraguay, the Ache, living under natural conditions, was studied. Data from this population turn out to be useful for considerations about evolutionary hypotheses on the aging phenomenon. 1) Ache show an age-related increasing mortality, which strongly limits the mean duration of life, as observed in other studies on mammal and bird species. 2) According to current theories on aging, in the wild very few or no individual reach old age and, so, aging cannot be directly influenced by natural selection. However, data from our population show that a significant proportion of the population reaches in the wild 60 and 70 years of age. 3) Data from Ache are also in agreement with the observation about an inverse correlation between extrinsic mortality and deaths due to the age-related increasing mortality. 4) For many gerontologists, the age-related decline of vital functions is a consequence of the gradual decline of cell turnover, genetically determined and regulated by the declining duplication capacities of stem cells. The current interpretation is that these restrictions are a general defense against the proliferation of any tumoral mass. However, among wild Ache cancer is virtually unknown in non-elderly subjects, and only among older individuals are there deaths attributable to oncological diseases. Moreover, fitness decline begins long before oncological diseases have fatal effects in significant numbers. This completely disproves the current hypothesis, because a supposed defense against a deadly disease cannot exterminate a population before the disease begins to kill. These data are consistent with similar data from other species studied under natural conditions, and they bring new arguments against the non-adaptive interpretation of aging and in support of the adaptive interpretation.

  4. Hypocretin (orexin) receptor subtypes differentially enhance acetylcholine release and activate g protein subtypes in rat pontine reticular formation.

    PubMed

    Bernard, René; Lydic, Ralph; Baghdoyan, Helen A

    2006-04-01

    The hypothalamic peptides hypocretin-1 (orexin A) and -2 (orexin B) promote wakefulness by mechanisms that are not well understood. Defects in hypocretinergic neurotransmission underlie the human sleep disorder narcolepsy. Hypocretins alter cell excitability via two receptor subtypes, hypocretin receptor subtype 1 (hcrt-r1) and hypocretin receptor subtype 2 (hcrt-r2). This study aimed to identify G protein subtypes activated by hypocretin in rat pontine reticular nucleus oral part (PnO) and the hypocretin receptor subtype modulating acetylcholine (ACh) release in the PnO. G protein activation was quantified using in vitro [(35)S]guanylyl-5'-O-(gamma-thio)triphosphate autoradiography. ACh release was measured using in vivo microdialysis and high-performance liquid chromatography. Hypocretin-1-stimulated G protein activation was significantly decreased by pertussis toxin, demonstrating that some hypocretin receptors in rat PnO activate inhibitory G proteins. Hypocretin-1-stimulated ACh release was not blocked by pertussis toxin, supporting the conclusion that the hypocretin receptors modulating ACh release in rat PnO activate stimulatory G proteins. Hypocretin-1 and -2 each caused a concentration-dependent increase in ACh release with similar potencies, indicating that hcrt-r2 modulates ACh release in PnO. Hypocretin-1 caused a significantly greater increase in ACh release than hypocretin-2, suggesting a role for hcrt-r1 in the modulation of PnO ACh release. Taken together, these data provide the first evidence that hypocretin receptors in rat PnO signal via inhibitory and stimulatory G proteins and that ACh release in rat PnO is modulated by hcrt-r2 and hcrt-r1. One mechanism by which hypocretin promotes arousal may be to increase ACh release in the pontine reticular formation.

  5. Enantiopure Cyclopropane-Bearing Pyridyldiazabicyclo[3.3.0]octanes as Selective α4β2-nAChR Ligands

    PubMed Central

    2014-01-01

    We report the synthesis and characterization of a series of enantiopure 5-cyclopropane-bearing pyridyldiazabicyclo[3.3.0]octanes that display low nanomolar binding affinities and act as functional agonists at α4β2-nicotinic acetylcholine receptor (nAChR) subtype. Structure–activity relationship studies revealed that incorporation of a cyclopropane-containing side chain at the 5-position of the pyridine ring provides ligands with improved subtype selectivity for nAChR β2 subunit-containing nAChR subtypes (β2*-nAChRs) over β4*-nAChRs compared to the parent compound 4. Compound 15 exhibited subnanomolar binding affinity for α4β2- and α4β2*-nAChRs with negligible interaction. Functional assays confirm selectivity for α4β2-nAChRs. Furthermore, using the SmartCube assay system, this ligand showed antidepressant, anxiolytic, and antipsychotic features, while mouse forced-swim assay further confirm the antidepressant-like property of 15. PMID:25408831

  6. Enantiopure Cyclopropane-Bearing Pyridyldiazabicyclo[3.3.0]octanes as Selective α4β2-nAChR Ligands.

    PubMed

    Onajole, Oluseye K; Eaton, J Brek; Lukas, Ronald J; Brunner, Dani; Thiede, Lucinda; Caldarone, Barbara J; Kozikowski, Alan P

    2014-11-13

    We report the synthesis and characterization of a series of enantiopure 5-cyclopropane-bearing pyridyldiazabicyclo[3.3.0]octanes that display low nanomolar binding affinities and act as functional agonists at α4β2-nicotinic acetylcholine receptor (nAChR) subtype. Structure-activity relationship studies revealed that incorporation of a cyclopropane-containing side chain at the 5-position of the pyridine ring provides ligands with improved subtype selectivity for nAChR β2 subunit-containing nAChR subtypes (β2*-nAChRs) over β4*-nAChRs compared to the parent compound 4. Compound 15 exhibited subnanomolar binding affinity for α4β2- and α4β2*-nAChRs with negligible interaction. Functional assays confirm selectivity for α4β2-nAChRs. Furthermore, using the SmartCube assay system, this ligand showed antidepressant, anxiolytic, and antipsychotic features, while mouse forced-swim assay further confirm the antidepressant-like property of 15.

  7. Complete Genome Sequence of Agrobacterium tumefaciens Ach5

    PubMed Central

    Huang, Ya-Yi; Cho, Shu-Ting; Lo, Wen-Sui; Wang, Yi-Chieh; Lai, Erh-Min

    2015-01-01

    Agrobacterium tumefaciens is a phytopathogenic bacterium that causes crown gall disease. The strain Ach5 was isolated from yarrow (Achillea ptarmica L.) and is the wild-type progenitor of other derived strains widely used for plant transformation. Here, we report the complete genome sequence of this bacterium. PMID:26044425

  8. Activation of muscarinic K+ current in guinea-pig atrial myocytes by a serum factor.

    PubMed Central

    Banach, K; Hüser, J; Lipp, P; Wellner, M C; Pott, L

    1993-01-01

    1. Atrial myocytes obtained by enzymatic perfusion of hearts from adult guinea-pigs and cultured for 0-14 days were studied using the whole-cell voltage-clamp technique. 2. Superfusion of the myocytes with diluted sera (1:100 to 1:10,000) from different species (human, horse, guinea-pig) evoked an inward rectifying K+ current. The voltage-dependent properties of this current were identical to those of the K+ current activated by acetylcholine (IK(ACh)). Current density in the presence of horse serum (1:100) approximately corresponded to the non-desensitizing fraction of IK(ACh) during superfusion with 1-2 x 10(-6) M ACh. 3. During a maximal serum-evoked current, application of ACh (10(-6) M) failed to evoke additional K+ current. After switching superfusion from serum-containing to serum-free solution, the K+ current decayed 1-2 orders of magnitude slower than ACh-activated IK(ACh). During the decay of the serum-evoked current, a proportional increase in responsiveness to ACh was recorded. During submaximal activation of K+ current by serum, a saturating concentration of ACh resulted in a total current that was identical to the current evoked by ACh alone minus the desensitizing component. Thus, activation of K+ current by serum caused desensitization of IK(ACh). From these results it is concluded that sera contain a factor that activates the same population of K+ channels as ACh. 4. Irreversible activation of IK(ACh) by ACh in myocytes dialysed with the GTP-analogue GTP-gamma-S abolished sensitivity to serum and vice versa. 5. The effect of serum was not modified by atropine (10(-6) M) which completely blocked the response to 2 x 10(-6) M ACh. Furthermore, theophylline (1 mM), which completely inhibited IK(ACh) activation by adenosine (100 microM), failed to inhibit the effect of serum. Thus, neither muscarinic nor purinergic (A1) receptors are involved. 6. The peptide somatostatin (10(-6) M) and the alpha 1-agonist phenylephrine (1 microM) which previously have

  9. Increasing physical activity of children during school recess.

    PubMed

    Hayes, Lynda B; Van Camp, Carole M

    2015-09-01

    Physical activity is crucial for children's health. Fitbit accelerometers were used to measure steps of 6 elementary students during recess. The intervention included reinforcement, self-monitoring, goal setting, and feedback. Steps taken during the intervention phase (M = 1,956 steps) were 47% higher than in baseline (M = 1,326 steps), and the percentage of recess spent in moderate-to-vigorous physical activity was higher during intervention (M = 25%) than in baseline (M = 4%). These methods successfully increased steps during recess and could be used to increase steps in other settings.

  10. The dual-acting AChE inhibitor and H3 receptor antagonist UW-MD-72 reverses amnesia induced by scopolamine or dizocilpine in passive avoidance paradigm in rats.

    PubMed

    Sadek, Bassem; Khan, Nadia; Darras, Fouad H; Pockes, Steffen; Decker, Michael

    2016-10-15

    Both the acetylcholine esterase (AChE) and the histamine H3 receptor (H3R) are involved in the metabolism and modulation of acetylcholine release and numerous other centrally acting neurotransmitters. Hence, dual-active AChE inhibitors (AChEIs) and H3R antagonists hold potential to treat cognitive disorders like Alzheimer's disease (AD). The novel dual-acting AChEI and H3R antagonist 7-(3-(piperidin-1-yl)propoxy)-2,3-dihydropyrrolo[2,1-b]quinazolin-9(1H)-one (UW-MD-72) shows excellent selectivity profiles over the AChE's isoenzyme butyrylcholinesterase (BChE) as well as high and balanced in-vitro affinities at both AChE and hH3R with IC50 of 5.4μM on hAChE and hH3R antagonism with Ki of 2.54μM, respectively. In the current study, the effects of UW-MD-72 (1.25, 2.5, and 5mg/kg, i.p.) on memory deficits induced by the muscarinic cholinergic antagonist scopolamine (SCO) and the non-competitive N-methyl-d-aspartate (NMDA) antagonist dizocilpine (DIZ) were investigated in a step-through type passive avoidance paradigm in adult male rats applying donepezil (DOZ) and pitolisant (PIT) as reference drugs. The results observed show that SCO (2mg/kg, i.p.) and DIZ (0.1mg/kg, i.p.) significantly impaired learning and memory in rats. However, acute systemic administration of UW-MD-72 significantly ameliorated the SCO- and DIZ-induced amnesic effects. Furthermore, the ameliorating activity of UW-MD-72 (1.25mg/kg, i.p.) in DIZ-induced amnesia was partly reversed when rats were pretreated with the centrally-acting H2R antagonist zolantidine (ZOL, 10mg/kg, i.p.), but not with the CNS penetrant H1R antagonist pyrilamine (PYR, 10mg/kg, i.p.). Moreover, ameliorative effect of UW-MD-72 (1.25mg/kg, i.p.) in DIZ-induced amnesia was strongly reversed when rats were pretreated with a combination of ZOL (10mg/kg, i.p.) and SCO (1.0mg/kg, i.p.), indicating that these memory enhancing effects were, in addition to other neural circuits, observed through histaminergic H2R as well as

  11. Biphasic cholinergic synaptic transmission controls action potential activity in thalamic reticular nucleus neurons.

    PubMed

    Sun, Yan-Gang; Pita-Almenar, Juan D; Wu, Chia-Shan; Renger, John J; Uebele, Victor N; Lu, Hui-Chen; Beierlein, Michael

    2013-01-30

    Cholinergic neurons in the basal forebrain and the brainstem form extensive projections to a number of thalamic nuclei. Activation of cholinergic afferents during distinct behavioral states can regulate neuronal firing, transmitter release at glutamatergic and GABAergic synapses, and synchrony in thalamic networks, thereby controlling the flow of sensory information. These effects are thought to be mediated by slow and persistent increases in extracellular ACh levels, resulting in the modulation of populations of thalamic neurons over large temporal and spatial scales. However, the synaptic mechanisms underlying cholinergic signaling in the thalamus are not well understood. Here, we demonstrate highly reliable cholinergic transmission in the mouse thalamic reticular nucleus (TRN), a brain structure essential for sensory processing, arousal, and attention. We find that ACh release evoked by low-frequency stimulation leads to biphasic excitatory-inhibitory (E-I) postsynaptic responses, mediated by the activation of postsynaptic α4β2 nicotinic ACh receptors (nAChRs) and M2 muscarinic ACh receptors (mAChRs), respectively. In addition, ACh can bind to mAChRs expressed near cholinergic release sites, resulting in autoinhibition of release. We show that the activation of postsynaptic nAChRs by transmitter release from only a small number of individual axons is sufficient to trigger action potentials in TRN neurons. Furthermore, short trains of cholinergic synaptic inputs can powerfully entrain ongoing TRN neuronal activity. Our study demonstrates fast and precise synaptic E-I signaling mediated by ACh, suggesting novel computational mechanisms for the cholinergic control of neuronal activity in thalamic circuits.

  12. Insecticidal activity of an essential oil of Tagetes patula L. (Asteraceae) on common bed bug Cimex lectularius L. and molecular docking of major compounds at the catalytic site of ClAChE1.

    PubMed

    Politi, Flávio Augusto Sanches; Nascimento, Juliana Damieli; da Silva, Alexander Alves; Moro, Isabela Jacob; Garcia, Mariana Lopes; Guido, Rafael Victório Carvalho; Pietro, Rosemeire Cristina Linhari Rodrigues; Godinho, Antônio Francisco; Furlan, Maysa

    2017-01-01

    Emerging resistance to insecticides has influenced pharmaceutical research and the search for alternatives to control the common bed bug Cimex lectularius. In this sense, natural products can play a major role. Tagetes patula, popularly known as dwarf marigold, is a plant native to North America with biocide potential. The aim of this work was to evaluate the biological activity of T. patula essential oil (EO) against adult common bed bugs via exposure to dry residues by the Impregnated Paper Disk Test (IPDT) using cypermethrin as a positive control. We selected the enzyme acetylcholinesterase as a target for modeling studies, with the intent of investigating the molecular basis of any biological activity of the EO. Chemical analysis of the EO was performed using gas chromatography coupled to mass spectrometry (GC-MS). Additionally, oral and dermal acute toxicity tests were performed according to Organization for Economic Cooperation and Development (OECD) guidelines. The sulforhodamine B assay (SRB) was performed to verify the cytotoxicity of EO to HaCaT cells. The EO eliminated 100 % of the bed bugs at 100 mg mL(-1) with an LC50 value of 15.85 mg mL(-1). GC-MS analysis identified α-terpinolene, limonene, piperitenone, and piperitone as major components of the mixture. Molecular modeling studies of these major compounds suggested that they are acetylcholinesterase inhibitors with good steric and electronic complementarity. The in vitro cytotoxicity evaluation revealed a LC50 = 37.06 μg mL(-1) and in vivo acute toxicity showed an LC50 >4000 mg kg(-1), indicating that the EO presents low risk of toxic side effects in humans. The T. patula essential oil components provide a promising strategy for controlling bed bug populations with low mammalian toxicity. These findings pave the way for further in vivo studies aimed at developing a safe and effective insecticide.

  13. Local school policies increase physical activity in Norwegian secondary schools

    PubMed Central

    Haug, Ellen; Torsheim, Torbjørn; Samdal, Oddrun

    2010-01-01

    SUMMARY The implementation of school policies to support the adoption of physical activity is one of the main strategies recommended to increase physical activity levels among this age group. However, documentation of the effect of such policies is so far limited. The purpose of this study was to explore policy-related practices to support physical activity in Norwegian secondary schools and their association with recess physical activity. Emphasis was given to examine the association between policies and physical activity, over and beyond, individual level interests and environmental factors and to examine cross-level interaction effects. This cross-sectional study was based on a nationally representative sample of Norwegian secondary schools and grade 8 students who participated in the Health Behaviour in School-aged Children (HBSC) 2005/06 study. The final sample comprised 68 schools and 1347 students. Data were collected through questionnaires. The results showed that schools with a written policy for physical activity and schools offering organized non-curricular physical activity several times a week had a higher proportion of students reporting daily participation in recess physical activity. Multilevel logistic regression analysis demonstrated a cross-level main effect of the policy index after controlling for sex, socio-economic status, individual-level interests and the physical environment. A significant contribution of adding the policy index to the prediction of recess physical activity above that provided by the individual-level interests and the physical environment was demonstrated. The results are encouraging and give scientific support to policy documents recommending the implementation of school policies to increase physical activity. PMID:19884244

  14. RAGE mediates the inactivation of nAChRs in sympathetic neurons under high glucose conditions.

    PubMed

    Chandna, Andrew R; Nair, Manoj; Chang, Christine; Pennington, Paul R; Yamamoto, Yasuhiko; Mousseau, Darrell D; Campanucci, Verónica A

    2015-02-01

    Autonomic dysfunction is a serious complication of diabetes and can lead to cardiovascular abnormalities and premature death. It was recently proposed that autonomic dysfunction is triggered by oxidation-mediated inactivation of neuronal nicotinic acetylcholine receptors (nAChRs), impairing synaptic transmission in sympathetic ganglia and resulting in autonomic failure. We investigated whether the receptor for advanced glycation end products (RAGE) and its role in the generation of reactive oxygen species (ROS) could be contributing to the events that initiate sympathetic malfunction under high glucose conditions. Using biochemical, live imaging and electrophysiological tools we demonstrated that exposure of sympathetic neurons to high glucose increases RAGE expression and oxidative markers, and that incubation with RAGE ligands (e.g. AGEs, S100 and HMGB1) mimics both ROS elevation and nAChR inactivation. In contrast, co-treatment with either antioxidants or an anti-RAGE IgG prevented the inactivation of nAChRs. Lastly, a role for RAGE in this context was corroborated by the lack of sensitivity of sympathetic neurons from RAGE knock-out mice to high glucose. These data define a pivotal role for RAGE in initiating the events associated with exposure of sympathetic neurons to high glucose, and strongly support RAGE signaling as a potential therapeutic target in the autonomic complications associated with diabetes.

  15. 3D MI-DRAGON: new model for the reconstruction of US FDA drug- target network and theoretical-experimental studies of inhibitors of rasagiline derivatives for AChE.

    PubMed

    Prado-Prado, Francisco; García-Mera, Xerardo; Escobar, Manuel; Alonso, Nerea; Caamaño, Olga; Yañez, Matilde; González-Díaz, Humberto

    2012-01-01

    The number of neurodegenerative diseases has been increasing in recent years. Many of the drug candidates to be used in the treatment of neurodegenerative diseases present specific 3D structural features. An important protein in this sense is the acetylcholinesterase (AChE), which is the target of many Alzheimer's dementia drugs. Consequently, the prediction of Drug-Protein Interactions (DPIs/nDPIs) between new drug candidates and specific 3D structure and targets is of major importance. To this end, we can use Quantitative Structure-Activity Relationships (QSAR) models to carry out a rational DPIs prediction. Unfortunately, many previous QSAR models developed to predict DPIs take into consideration only 2D structural information and codify the activity against only one target. To solve this problem we can develop some 3D multi-target QSAR (3D mt-QSAR) models. In this study, using the 3D MI-DRAGON technique, we have introduced a new predictor for DPIs based on two different well-known software. We have used the MARCH-INSIDE (MI) and DRAGON software to calculate 3D structural parameters for drugs and targets respectively. Both classes of 3D parameters were used as input to train Artificial Neuronal Network (ANN) algorithms using as benchmark dataset the complex network (CN) made up of all DPIs between US FDA approved drugs and their targets. The entire dataset was downloaded from the DrugBank database. The best 3D mt-QSAR predictor found was an ANN of Multi-Layer Perceptron-type (MLP) with profile MLP 37:37-24-1:1. This MLP classifies correctly 274 out of 321 DPIs (Sensitivity = 85.35%) and 1041 out of 1190 nDPIs (Specificity = 87.48%), corresponding to training Accuracy = 87.03%. We have validated the model with external predicting series with Sensitivity = 84.16% (542/644 DPIs; Specificity = 87.51% (2039/2330 nDPIs) and Accuracy = 86.78%. The new CNs of DPIs reconstructed from US FDA can be used to explore large DPI databases in order to discover both new drugs

  16. Using the Web to Increase Physical Activity in College Students

    ERIC Educational Resources Information Center

    Magoc, Dejan; Tomaka, Joe; Bridges-Arzaga, Amber

    2011-01-01

    Objectives: To evaluate the effectiveness of a theoretically based and Web-delivered intervention using common course technology for increasing physical activity in a college student sample. Methods: One hundred four students randomly participated in either a Web-based intervention involving 7 theory-based learning lessons or a control group that…

  17. Increased proteasome activity determines human embryonic stem cell identity

    PubMed Central

    Vilchez, David; Boyer, Leah; Morantte, Ianessa; Lutz, Margaret; Merkwirth, Carsten; Joyce, Derek; Spencer, Brian; Page, Lesley; Masliah, Eliezer; Berggren, W. Travis; Gage, Fred H.; Dillin, Andrew

    2016-01-01

    Embryonic stem cells are able to replicate continuously in the absence of senescence and, therefore, are immortal in culture1,2. While genome stability is central for survival of stem cells; proteome stability may play an equally important role in stem cell identity and function. Additionally, with the asymmetric divisions invoked by stem cells, the passage of damaged proteins to daughter cells could potentially destroy the resulting lineage of cells. We hypothesized that stem cells have an increased proteostasis ability compared to their differentiated counterparts and asked whether proteasome activity differed among human embryonic stem cells (hESCs). Notably, hESC populations exhibit a high proteasome activity that is correlated with increased levels of the 19S proteasome subunit PSMD11/RPN-63–5 and a corresponding increased assembly of the 26S/30S proteasome. Ectopic expression of PSMD11 is sufficient to increase proteasome assembly and activity. Proteasome inhibition affects pluripotency of hESCs inducing differentiation towards specific cell lineages. FOXO4, an insulin/IGF-1 responsive transcription factor associated with long lifespan in invertebrates6,7, regulates proteasome activity by modulating the expression of PSMD11 in hESCs. Our results establish a novel regulation of proteostasis in hESCs that links longevity and stress resistance in invertebrates with hESC function and identity. PMID:22972301

  18. Texting to increase adolescent physical activity: Feasibility assessment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feasibility trials assess whether a behavior change program warrants a definite trial evaluation. This paper reports the feasibility of an intervention consisting of Self Determination Theory-informed text messages, pedometers, and goal prompts to increase adolescent physical activity. A 4-group ran...

  19. Reduced Frontal Activation with Increasing 2nd Language Proficiency

    ERIC Educational Resources Information Center

    Stein, Maria; Federspiel, Andrea; Koenig, Thomas; Wirth, Miranka; Lehmann, Christoph; Wiest, Roland; Strik, Werner; Brandeis, Daniel; Dierks, Thomas

    2009-01-01

    The factors influencing the degree of separation or overlap in the neuronal networks responsible for the processing of first and second language are still subject to investigation. This longitudinal study investigates how increasing second language proficiency influences activation differences during lexico-semantic processing of first and second…

  20. Games for increasing physical activity: Mechanisms for change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A small conference was held in Houston, TX, in May 2014, to address how to enhance exergames to increase physical activity. Several leading researchers were asked to address specific topics. Attendees came from across the globe. This Games for Health Journal Special Issue is devoted to sharing the a...

  1. Age-dependent changes in plasma and brain cholinesterase activities of house wrens and European starlings.

    PubMed

    Mayack, David T; Martin, Tim

    2003-07-01

    We determined age-dependent changes in plasma and brain cholinesterase (ChE) activity for two species of passerines: house wren (Troglodytes aedon) and European starling (Sturnus vulgaris, starling). In plasma from nestlings of both species, total ChE activity increased with age, acetycholinesterase (AChE, EC 3.1.1.7) activity declined rapidly immediately after hatching, and butyrylcholinesterase (BChE, EC 3.1.1.8) activity increased steadily. For both species, total ChE and BChE activities and the BChE:AChE ratio in plasma were significantly greater in adults than nestlings suggesting trends observed in nestlings continue post fledging. In older nestlings and adults, AChE activity in plasma was significantly greater and BChE:AChE ratio less in house wrens than starlings. For house wrens as compared with starlings, ChE activity in brain increased at a significantly greater rate with age in nestlings and was significantly greater in adults. However, ChE activity in brain was similar at fledging for both species suggesting that the increase in ChE in brain is more directly related to ontogeny than chronologic age in nestlings of passerines. For both species, ChE activity increased significantly with brain weight of nestlings but not adults. House wrens hold similar patterns of age-dependent change in ChE activity in common with starlings but also exhibit differences in AChE activity in plasma that should be considered as a factor potentially affecting their relative toxicologic response to ChE inhibitors.

  2. Increased Acetylcholinesterase Expression in Bumble Bees During Neonicotinoid-Coated Corn Sowing.

    PubMed

    Samson-Robert, Olivier; Labrie, Geneviève; Mercier, Pierre-Luc; Chagnon, Madeleine; Derome, Nicolas; Fournier, Valérie

    2015-07-30

    While honey bee exposure to systemic insecticides has received much attention, impacts on wild pollinators have not been as widely studied. Neonicotinoids have been shown to increase acetylcholinesterase (AChE) activity in honey bees at sublethal doses. High AChE levels may therefore act as a biomarker of exposure to neonicotinoids. This two-year study focused on establishing whether bumble bees living and foraging in agricultural areas using neonicotinoid crop protection show early biochemical signs of intoxication. Bumble bee colonies (Bombus impatiens) were placed in two different agricultural cropping areas: 1) control (≥ 3 km from fields planted with neonicotinoid-treated seeds) or 2) exposed (within 500 m of fields planted with neonicotinoid-treated seeds), and maintained for the duration of corn sowing. As determined by Real Time qPCR, AChE mRNA expression was initially significantly higher in bumble bees from exposed sites, then decreased throughout the planting season to reach a similar endpoint to that of bumble bees from control sites. These findings suggest that exposure to neonicotinoid seed coating particles during the planting season can alter bumble bee neuronal activity. To our knowledge, this is the first study to report in situ that bumble bees living in agricultural areas exhibit signs of neonicotinoid intoxication.

  3. Increased Acetylcholinesterase Expression in Bumble Bees During Neonicotinoid-Coated Corn Sowing

    PubMed Central

    Samson-Robert, Olivier; Labrie, Geneviève; Mercier, Pierre-Luc; Chagnon, Madeleine; Derome, Nicolas; Fournier, Valérie

    2015-01-01

    While honey bee exposure to systemic insecticides has received much attention, impacts on wild pollinators have not been as widely studied. Neonicotinoids have been shown to increase acetylcholinesterase (AChE) activity in honey bees at sublethal doses. High AChE levels may therefore act as a biomarker of exposure to neonicotinoids. This two-year study focused on establishing whether bumble bees living and foraging in agricultural areas using neonicotinoid crop protection show early biochemical signs of intoxication. Bumble bee colonies (Bombus impatiens) were placed in two different agricultural cropping areas: 1) control (≥3 km from fields planted with neonicotinoid-treated seeds) or 2) exposed (within 500 m of fields planted with neonicotinoid-treated seeds), and maintained for the duration of corn sowing. As determined by Real Time qPCR, AChE mRNA expression was initially significantly higher in bumble bees from exposed sites, then decreased throughout the planting season to reach a similar endpoint to that of bumble bees from control sites. These findings suggest that exposure to neonicotinoid seed coating particles during the planting season can alter bumble bee neuronal activity. To our knowledge, this is the first study to report in situ that bumble bees living in agricultural areas exhibit signs of neonicotinoid intoxication. PMID:26223214

  4. Hypocholesterolemia in chronic anemias with increased erythropoietic activity.

    PubMed

    Shalev, Hanna; Kapelushnik, Joseph; Moser, Asher; Knobler, Hilla; Tamary, Hannah

    2007-03-01

    Hypocholesterolemia of unknown etiology has been previously described in various chronic anemias. Few small studies also suggested that those patients have a lower incidence of atherosclerotic events. The aim of our study was to determine the extent of hypocholesterolemia in various types of anemias. We studied 59 patients with chronic anemias associated with high-erythropoietic activity (thalassemia intermedia, congenital dyserythropoietic anemia type I, congenital spherocytosis), 8 patients with low-erythropoietic activity anemias (acquired aplastic anemia, Fanconi anemia, and Diamond Blackfan anemia), and 20 healthy controls. Mean serum cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol, triglycerides, hemoglobin, serum ferritin, soluble transferrin receptor (STR), and serum erythropoietin levels were determined in each patient. All patients with chronic anemia and increased erythropoietic activity had hypocholesterolemia, whereas none of those with low erythropoietic activity was hypocholesterolemic. Mean serum cholesterol, HDL cholesterol, and LDL cholesterol levels were found to be significantly lower in the high-erythropoietic activity group (80+/-19 mg/dl; 31+/-10 mg/dl; 35+/-14 mg/dl, respectively) compared with the control group (P<0.001; 0.001; 0.001, respectively) and the low-erythropoietic activity group (P<0.001; 0.001; 0.01, respectively). Significant inverse correlation (R2=0.507) was observed between serum cholesterol and STR levels, which in the absence of iron deficiency reflect bone marrow activity. Taken together, our results imply that hypocholesterolemia accompanies anemias with high-erythropoietic activity. We suggest that the high-erythropoitic activity-associated hypocholesterolemia is due to increased cholesterol requirements by the proliferating erythoid cells. Further studies are needed to elucidate the exact mechanism and the possible clinical consequences of this phenomenon.

  5. Increased matriptase zymogen activation in inflammatory skin disorders

    PubMed Central

    Chen, Cheng-Jueng; Wu, Bai-Yao; Tsao, Pai-In; Chen, Chi-Yung; Wu, Mei-Hsuan; Chan, Yee Lam E.; Lee, Herng-Sheng; Johnson, Michael D.; Eckert, Richard L.; Chen, Ya-Wen; Chou, Fengpai; Lin, Chen-Yong

    2011-01-01

    Matriptase, a type 2 transmembrane serine protease, and its inhibitor hepatocyte growth factor activator inhibitor (HAI)-1 are required for normal epidermal barrier function, and matriptase activity is tightly regulated during this process. We therefore hypothesized that this protease system might be deregulated in skin disease. To test this, we examined the level and activation state of matriptase in examples of 23 human skin disorders. We first examined matriptase and HAI-1 protein distribution in normal epidermis. Matriptase was detected at high levels at cell-cell junctions in the basal layer and spinous layers but was present at minimal levels in the granular layer. HAI-1 was distributed in a similar pattern, except that high-level expression was retained in the granular layer. This pattern of expression was retained in most skin disorders. We next examined the distribution of activated matriptase. Although activated matriptase is not detected in normal epidermis, a dramatic increase is seen in keratinocytes at the site of inflammation in 16 different skin diseases. To gain further evidence that activation is associated with inflammatory stimuli, we challenged HaCaT cells with acidic pH or H2O2 and observed matriptase activation. These findings suggest that inflammation-associated reactive oxygen species and tissue acidity may enhance matriptase activation in some skin diseases. PMID:21123732

  6. Primary cultures of rat cortical microglia treated with nicotine increases in the expression of excitatory amino acid transporter 1 (GLAST) via the activation of the α7 nicotinic acetylcholine receptor.

    PubMed

    Morioka, N; Tokuhara, M; Nakamura, Y; Idenoshita, Y; Harano, S; Zhang, F F; Hisaoka-Nakashima, K; Nakata, Y

    2014-01-31

    Although the clearance of glutamate from the synapse under physiological conditions is performed by astrocytic glutamate transporters, their expression might be diminished under pathological conditions. Microglia glutamate transporters, however, might serve as a back-up system when astrocytic glutamate uptake is impaired, and could have a prominent neuroprotective function under pathological conditions. In the current study, the effect of nicotine, well known as a neuroprotective molecule, on the function of glutamate transporters in cultured rat cortical microglia was examined. Reverse transcription polymerase chain reaction and pharmacological approaches demonstrated that, glutamate/aspartate transporter (GLAST), not glutamate transporter 1 (GLT-1), is the major functional glutamate transporter in cultured cortical microglia. Furthermore, the α7 subunit was demonstrated to be the key subunit comprising nicotinic acetylcholine (nACh) receptors in these cells. Treatment of cortical microglia with nicotine led to a significant increase of GLAST mRNA expression and (14)C-glutamate uptake in a concentration- and time-dependent manner, which were markedly inhibited by pretreatment with methyllycaconitine, a selective α7 nACh receptor antagonist. The nicotine-induced expression of GLAST mRNA and protein is mediated through an inositol trisphosphate (IP3) and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) depend intracellular pathway, since pretreatment with either xestospongin C, an IP3 receptor antagonist, or KN-93, a CaMKII inhibitor, blocked GLAST expression. Together, these findings indicate that activation of nACh receptors, specifically those expressing the α7 subunit, on cortical microglia could be a key mechanism of the neuroprotective effect of nACh receptor ligands such as nicotine.

  7. Chromosome 1 replacement increases brain orexins and antidepressive measures without increasing locomotor activity.

    PubMed

    Feng, Pingfu; Hu, Yufen; Vurbic, Drina; Akladious, Afaf; Strohl, Kingman P

    2014-12-01

    Decreased orexin level has been well demonstrated in patients suffering from narcolepsy, depression accompanied with suicide attempt; obstructive sleep apnea and comorbidity were also demonstrated in these diseases. As C57BL/6J (B6) mice are more "depressed" and have lower brain orexins than A/J mice, B6 mice having chromosome 1 replacement (B6A1 mice) might have restored orexin levels and less depressive behavior. We studied the behavior of 4-6 month old B6, A/J and B6A1 mice with forced swim, tail suspension, and locomotor activity tests. The animals were then sacrificed and hypothalamus and medullas dissected from brain tissue. Orexins-A and -B were determined by radioimmunoassay. Compared with A/J mice, B6 mice displayed several signs of depression, including increased immobility, increased locomotors activity, and decreased orexin A and -B levels in both the hypothalamus and medulla. Compared to B6 mice, B6A1 mice exhibited significantly higher levels of orexins-A and -B in both brain regions. B6A1 mice also exhibited antidepressive features in most of measured variables, including decreased locomotor activity, decreased immobility and increased swim in tail suspension test; compared with B6 mice, however. B6A1 mice also reversed immobility in the early phase of the swim test. In summary, B6 mice exhibited depressive attributes compared with A/J mice, including increased locomotor activity, greater immobility, and decreased brain orexins, these were largely reversed in B6A1 mice. We conclude that orexin levels modulate these B6 behaviors, likely due to expression of A/J alleles on Chromosome 1.

  8. Distinct profiles of alpha7 nAChR positive allosteric modulation revealed by structurally diverse chemotypes.

    PubMed

    Grønlien, Jens Halvard; Håkerud, Monika; Ween, Hilde; Thorin-Hagene, Kirsten; Briggs, Clark A; Gopalakrishnan, Murali; Malysz, John

    2007-09-01

    Selective modulation of alpha7 nicotinic acetylcholine receptors (nAChRs) is thought to regulate processes impaired in schizophrenia, Alzheimer's disease, and other dementias. One approach to target alpha7 nAChRs is by positive allosteric modulation. Structurally diverse compounds, including PNU-120596, 4-naphthalene-1-yl-3a,4,5,9b-tetrahydro-3-H-cyclopenta[c]quinoline-8-sulfonic acid amide (TQS), and 5-hydroxyindole (5-HI) have been identified as positive allosteric modulators (PAMs), but their receptor interactions and pharmacological profiles remain to be fully elucidated. In this study, we investigated interactions of these compounds at human alpha7 nAChRs, expressed in Xenopus laevis oocytes, along with genistein, a tyrosine kinase inhibitor. Genistein was found to function as a PAM. Two types of PAM profiles were observed. 5-HI and genistein predominantly affected the apparent peak current (type I) whereas PNU-120596 and TQS increased the apparent peak current and evoked a distinct weakly decaying current (type II). Concentration-responses to agonists [ACh, 3-[(3E)-3-[(2,4-dimethoxyphenyl)methylidene]-5,6-dihydro-4H-pyridin-2-yl]pyridine dihydrochloride (GTS-21), and N-[(3R)-1-azabicyclo[2.2.2]oct-3-yl]-4-chlorobenzamide hydrochloride (PNU-282987)] were potentiated by both types, although type II PAMs had greater effects. When applied after alpha7 nAChRs were desensitized, type II, but not type I, PAMs could reactivate alpha7 currents. Both types of PAMs also increased the ACh-evoked alpha7 window currents, with type II PAMs generally showing larger potentiation. None of the PAMs tested increased nicotine-evoked Ca(2+) transients in human embryonic kidney 293 cells expressing human alpha4beta2 or alpha3beta4 nAChRs, although some inhibition was noted for 5-HI, genistein, and TQS. In summary, our studies reveal two distinct alpha7 PAM profiles, which could offer unique opportunities for modulating alpha7 nAChRs in vivo and in the development of novel

  9. High therapeutic potential of positive allosteric modulation of α7 nAChRs in a rat model of traumatic brain injury: Proof-of-concept

    PubMed Central

    Gatson, Joshua W.; Simpkins, James W.; Uteshev, Victor V.

    2015-01-01

    There are currently no clinically-efficacious drug therapies to treat brain damage secondary to traumatic brain injury (TBI). In this proof-of-concept study, we used a controlled cortical impact model of TBI in young adult rats to explore a novel promising approach that utilizes PNU-120596, a previously-reported highly selective Type-II positive allosteric modulator (α7-PAM) of α7 nicotinic acetylcholine receptors (nAChRs). α7-PAMs enhance and prolong α7 nAChR activation, but do not activate α7 nAChRs when administered without an agonist. The rational basis for the use of an α7-PAM as a post-TBI treatment is tripartite and arises from: 1) the intrinsic ability of brain injury to elevate extracellular levels of choline (a ubiquitous cell membrane-building material and a selective endogenous agonist of α7 nAChRs) due to the breakdown of cell membranes near the site and time of injury; 2) the ubiquitous expression of functional α7 nAChRs in neuronal and glial/immune brain cells; and 3) the potent neuroprotective and anti-inflammatory effects of α7 nAChR activation. Therefore, both neuroprotective and anti-inflammatory effects can be achieved post-TBI by targeting only a single player (i.e., the α7 nAChR) using α7-PAMs to enhance the activation of α7 nAChRs by injury-elevated extracellular choline. Our data support this hypothesis and demonstrate that subcutaneous administration of PNU-120596 post-TBI in young adult rats significantly reduces both brain cell damage and reactive gliosis. Therefore, our results introduce post-TBI systemic administration of α7-PAMs as a promising therapeutic intervention that could significantly restrict brain injury post-TBI and facilitate recovery of TBI patients. PMID:25647232

  10. In vitro and in vivo profiles of ACH-702, an isothiazoloquinolone, against bacterial pathogens.

    PubMed

    Pucci, Michael J; Podos, Steven D; Thanassi, Jane A; Leggio, Melissa J; Bradbury, Barton J; Deshpande, Milind

    2011-06-01

    ACH-702, a novel isothiazoloquinolone (ITQ), was assessed for antibacterial activity against a panel of Gram-positive and Gram-negative clinical isolates and found to possess broad-spectrum activity, especially against antibiotic-resistant Gram-positive strains, including methicillin-resistant Staphylococcus aureus (MRSA). For Gram-negative bacteria, ACH-702 showed exceptional potency against Haemophilus influenzae, Moraxella catarrhalis, and a Neisseria sp. but was less active against members of the Enterobacteriaceae. Good antibacterial activity was also evident against several anaerobes as well as Legionella pneumophila and Mycoplasma pneumoniae. Excellent bactericidal activity was observed for ACH-702 against several bacterial pathogens in time-kill assays, and postantibiotic effects (PAEs) of >1 h were evident with both laboratory and clinical strains of staphylococci at 10 × MIC and similar in most cases to those observed for moxifloxacin at the same MIC multiple. In vivo efficacy was demonstrated against S. aureus with murine sepsis and thigh infection models, with decreases in the number of CFU/thigh equal to or greater than those observed after vancomycin treatment. Macromolecular synthesis assays showed specific dose-dependent inhibition of DNA replication in staphylococci, and biochemical analyses indicated potent dual inhibition of two essential DNA replication enzymes: DNA gyrase and topoisomerase IV. Additional biological data in support of an effective dual targeting mechanism of action include the following: low MIC values (≤0.25 μg/ml) against staphylococcal strains with single mutations in both gyrA and grlA (parC), retention of good antibacterial activity (MICs of ≤0.5 μg/ml) against staphylococcal strains with two mutations in both gyrA and grlA, and low frequencies for the selection of higher-level resistance (<10⁻¹⁰). These promising initial data support further study of isothiazoloquinolones as potential clinical candidates.

  11. Methods of increasing secretion of polypeptides having biological activity

    SciTech Connect

    Merino, Sandra

    2013-10-01

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  12. Methods of increasing secretion of polypeptides having biological activity

    DOEpatents

    Merino, Sandra

    2014-10-28

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  13. Methods of increasing secretion of polypeptides having biological activity

    DOEpatents

    Merino, Sandra

    2014-05-27

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  14. Methods of increasing secretion of polypeptides having biological activity

    SciTech Connect

    Merino, Sandra

    2015-04-14

    The present invention relates to methods for producing a secreted polypeptide having biological activity, comprising: (a) transforming a fungal host cell with a fusion protein construct encoding a fusion protein, which comprises: (i) a first polynucleotide encoding a signal peptide; (ii) a second polynucleotide encoding at least a catalytic domain of an endoglucanase or a portion thereof; and (iii) a third polynucleotide encoding at least a catalytic domain of a polypeptide having biological activity; wherein the signal peptide and at least the catalytic domain of the endoglucanase increases secretion of the polypeptide having biological activity compared to the absence of at least the catalytic domain of the endoglucanase; (b) cultivating the transformed fungal host cell under conditions suitable for production of the fusion protein; and (c) recovering the fusion protein, a component thereof, or a combination thereof, having biological activity, from the cultivation medium.

  15. Fo Shou San, an ancient Chinese herbal decoction, protects endothelial function through increasing endothelial nitric oxide synthase activity.

    PubMed

    Bi, Cathy W C; Xu, Li; Tian, Xiao Yu; Liu, Jian; Zheng, Ken Y Z; Lau, Chi Wai; Lau, David T W; Choi, Roy C Y; Dong, Tina T X; Huang, Yu; Tsim, Karl W K

    2012-01-01

    Fo Shou San (FSS) is an ancient herbal decoction comprised of Chuanxiong Rhizoma (CR; Chuanxiong) and Angelicae Sinensis Radix (ASR; Danggui) in a ratio of 2:3. Previous studies indicate that FSS promotes blood circulation and dissipates blood stasis, thus which is being used widely to treat vascular diseases. Here, we aim to determine the cellular mechanism for the vascular benefit of FSS. The treatment of FSS reversed homocysteine-induced impairment of acetylcholine (ACh)-evoked endothelium-dependent relaxation in aortic rings, isolated from rats. Like radical oxygen species (ROS) scavenger tempol, FSS attenuated homocysteine-stimulated ROS generation in cultured human umbilical vein endothelial cells (HUVECs), and it also stimulated the production of nitric oxide (NO) as measured by fluorescence dye and biochemical assay. In addition, the phosphorylation levels of both Akt kinase and endothelial NO synthases (eNOS) were markedly increased by FSS treatment, which was abolished by an Akt inhibitor triciribine. Likewise, triciribine reversed FSS-induced NO production in HUVECs. Finally, FSS elevated intracellular Ca(2+) levels in HUVECs, and the Ca(2+) chelator BAPTA-AM inhibited the FSS-stimulated eNOS phosphorylation. The present results show that this ancient herbal decoction benefits endothelial function through increased activity of Akt kinase and eNOS; this effect is causally via a rise of intracellular Ca(2+) and a reduction of ROS.

  16. Local salt substitutes “Obu-otoyo” activate acetylcholinesterase and butyrylcholinesterase and induce lipid peroxidation in rat brain

    PubMed Central

    Oboh, Ganiyu; Ademiluyi, Adedayo O.

    2015-01-01

    Evidence has shown that ingestion of heavy metals can lead to neurodegenerative diseases. This study aimed to investigate the neurotoxic potential of salt substitutes (Obu-Otoyo); salt A (made by burning palm kernel shaft then soaked in water overnight and the extract from the resulting residue is used as the salt substitute) and salt B (an unrefined salt mined from a local site at Ilobu town, Osun-State, Nigeria) by assessing their effect on some key enzymes linked with neurodegenerative disease [acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities] as well as on malondialdehyde (MDA) content of the rat brain. Salt substitutes were fed to normal rats as dietary inclusion at doses of 0.5 and 1.0% for 30 days. Thereafter, the effect of the salt substitutes on AChE and BChE activities as well as on MDA level in the rat brain was determined. The results revealed that the salt substitutes caused a significant (p<0.05) increase in both AChE and BChE activity and also induced lipid peroxidation in the brain of rats in vivo as well as under in vitro condition in a dose-dependent manner. The effect of the salt substitutes on AChE and BChE activities could be attributed to the presence of some toxic heavy metals. Therefore, the ability of the salt substitutes to induce lipid peroxidation and activate AChE and BChE activities could provide some possible mechanism for their neurotoxic effect. PMID:27486373

  17. Local salt substitutes "Obu-otoyo" activate acetylcholinesterase and butyrylcholinesterase and induce lipid peroxidation in rat brain.

    PubMed

    Akinyemi, Ayodele J; Oboh, Ganiyu; Ademiluyi, Adedayo O

    2015-09-01

    Evidence has shown that ingestion of heavy metals can lead to neurodegenerative diseases. This study aimed to investigate the neurotoxic potential of salt substitutes (Obu-Otoyo); salt A (made by burning palm kernel shaft then soaked in water overnight and the extract from the resulting residue is used as the salt substitute) and salt B (an unrefined salt mined from a local site at Ilobu town, Osun-State, Nigeria) by assessing their effect on some key enzymes linked with neurodegenerative disease [acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities] as well as on malondialdehyde (MDA) content of the rat brain. Salt substitutes were fed to normal rats as dietary inclusion at doses of 0.5 and 1.0% for 30 days. Thereafter, the effect of the salt substitutes on AChE and BChE activities as well as on MDA level in the rat brain was determined. The results revealed that the salt substitutes caused a significant (p<0.05) increase in both AChE and BChE activity and also induced lipid peroxidation in the brain of rats in vivo as well as under in vitro condition in a dose-dependent manner. The effect of the salt substitutes on AChE and BChE activities could be attributed to the presence of some toxic heavy metals. Therefore, the ability of the salt substitutes to induce lipid peroxidation and activate AChE and BChE activities could provide some possible mechanism for their neurotoxic effect.

  18. Luminal acetylcholine does not affect the activity of the CFTR in tracheal epithelia of pigs.

    PubMed

    Dittrich, Nikolaus P; Kummer, Wolfgang; Clauss, Wolfgang G; Fronius, Martin

    2015-11-01

    Fluid homeostasis mediated by the airway epithelium is required for proper lung function, and the CFTR (cystic fibrosis transmembrane conductance regulator) Cl(-) channel is crucial for these processes. Luminal acetylcholine (ACh) acts as an auto-/paracrine mediator to activate Cl(-) channels in airway epithelia and evidence exists showing that nicotinic ACh receptors activate CFTR in murine airway epithelia. The present study investigated whether or not luminal ACh regulates CFTR activity in airway epithelia of pigs, an emerging model for investigations of human airway disease and cystic fibrosis (CF) in particular. Transepithelial ion currents of freshly dissected pig tracheal preparations were measured with Ussing chambers. Application of luminal ACh (100 μM) induced an increase of the short-circuit current (I(SC)). The ACh effect was mimicked by muscarine and pilocarpine (100 μM each) and was sensitive to muscarinic receptor antagonists (atropine, 4-DAMP, pirenzepine). No changes of the I(SC) were observed by nicotine (100 μM) and ACh responses were not affected by nicotine or mecamylamine (25 μM). Luminal application of IBMX (I, 100 μM) and forskolin (F, 10 μM), increase the I(SC) and the I/F-induced current were decreased by the CFTR inhibitor GlyH-101 (GlyH, 50 μM) indicating increased CFTR activity by I/F. In contrast, GlyH did not affect the ACh-induced current, indicating that the ACh response does not involve the activation of the CFTR. Results from this study suggest that luminal ACh does not regulate the activity of the CFTR in tracheal epithelia of pigs which opposes observation from studies using mice airway epithelium.

  19. Plant species richness increases phosphatase activities in an experimental grassland

    NASA Astrophysics Data System (ADS)

    Hacker, Nina; Wilcke, Wolfgang; Oelmann, Yvonne

    2014-05-01

    Plant species richness has been shown to increase aboveground nutrient uptake requiring the mobilization of soil nutrient pools. For phosphorus (P) the underlying mechanisms for increased P release in soil under highly diverse grassland mixtures remain obscure because aboveground P storage and concentrations of inorganic and organic P in soil solution and differently reactive soil P pools are unrelated (Oelmann et al. 2011). The need of plants and soil microorganisms for P can increase the exudation of enzymes hydrolyzing organically bound P (phosphatases) which might represent an important release mechanism of inorganic P in a competitive environment such as highly diverse grassland mixtures. Our objectives were to test the effects of i) plant functional groups (legumes, grasses, non-leguminous tall and small herbs), and of (ii) plant species richness on microbial P (Pmic) and phosphatase activities in soil. In autumn 2013, we measured Pmic and alkaline phosphomonoesterase and phosphodiesterase activities in soil of 80 grassland mixtures comprising different community compositions and species richness (1, 2, 4, 8, 16, 60) in the Jena Experiment. In general, Pmic and enzyme activities were correlated (r = 0.59 and 0.46 for phosphomonoesterase and phosphodiesterase activities, respectively; p

  20. Exercising self-control increases relative left frontal cortical activation.

    PubMed

    Schmeichel, Brandon J; Crowell, Adrienne; Harmon-Jones, Eddie

    2016-02-01

    Self-control refers to the capacity to override or alter a predominant response tendency. The current experiment tested the hypothesis that exercising self-control temporarily increases approach motivation, as revealed by patterns of electrical activity in the prefrontal cortex. Participants completed a writing task that did vs did not require them to exercise self-control. Then they viewed pictures known to evoke positive, negative or neutral affect. We assessed electroencephalographic (EEG) activity while participants viewed the pictures, and participants reported their trait levels of behavioral inhibition system (BIS) and behavioral activation system (BAS) sensitivity at the end of the study. We found that exercising (vs not exercising) self-control increased relative left frontal cortical activity during picture viewing, particularly among individuals with relatively higher BAS than BIS, and particularly during positive picture viewing. A similar but weaker pattern emerged during negative picture viewing. The results suggest that exercising self-control temporarily increases approach motivation, which may help to explain the aftereffects of self-control (i.e. ego depletion).

  1. Assessment of the functionality and stability of detergent purified nAChR from Torpedo using lipidic matrixes and macroscopic electrophysiology.

    PubMed

    Padilla-Morales, Luis F; Colón-Sáez, José O; González-Nieves, Joel E; Quesada-González, Orestes; Lasalde-Dominicci, José A

    2016-01-01

    In our previous study we examined the functionality and stability of nicotinic acetylcholine receptor (nAChR)-detergent complexes (nAChR-DCs) from affinity-purified Torpedo californica (Tc) using fluorescence recovery after photobleaching (FRAP) in Lipidic Cubic Phase (LCP) and planar lipid bilayer (PLB) recordings for phospholipid and cholesterol like detergents. In the present study we enhanced the functional characterization of nAChR-DCs by recording macroscopic ion channel currents in Xenopus oocytes using the two electrode voltage clamp (TEVC). The use of TEVC allows for the recording of macroscopic currents elicited by agonist activation of nAChR-DCs that assemble in the oocyte plasma membrane. Furthermore, we examined the stability of nAChR-DCs, which is obligatory for the nAChR crystallization, using a 30 day FRAP assay in LCP for each detergent. The present results indicate a marked difference in the fractional fluorescence recovery (ΔFFR) within the same detergent family during the 30 day period assayed. Within the cholesterol analog family, sodium cholate and CHAPSO displayed a minimum ΔFFR and a mobile fraction (MF) over 80%. In contrast, CHAPS and BigCHAP showed a marked decay in both the mobile fraction and diffusion coefficient. nAChR-DCs containing phospholipid analog detergents with an alkylphosphocholine (FC) and lysofoscholine (LFC) of 16 carbon chains (FC-16, LFC-16) were more effective in maintaining a mobile fraction of over 80% compared to their counterparts with shorter acyl chain (C12, C14). The significant differences in macroscopic current amplitudes, activation and desensitization rates among the different nAChR-DCs evaluated in the present study allow to dissect which detergent preserves both, agonist activation and ion channel function. Functionality assays using TEVC demonstrated that LFC16, LFC14, and cholate were the most effective detergents in preserving macroscopic ion channel function, however, the nAChR-cholate complex

  2. Acetylcholinesterase inhibitory activity of uleine from Himatanthus lancifolius.

    PubMed

    Seidl, Cláudia; Correia, Beatriz L; Stinghen, Andréa E M; Santos, Cid A M

    2010-01-01

    Application of acetylcholinesterase (AChE) inhibitors is the primary treatment for Alzheimer's disease. Alkaloids, such as physostigmine, galanthamine, and huperzine A, play an important role as AChE inhibitors. The aim of this work was to evaluate Himatanthus lancifolius (Muell. Arg.) Woodson, a Brazilian species of Apocynaceae, and its main indole alkaloid uleine, in order to identify new AChE inhibitors. The plant fluid extract, fractions, and uleine were tested for AChE inhibitory activity using Ellman's colorimetric method for thin-layer chromatography (TLC), 96-well microplates, and also Marston's TLC colorimetric method. Both TLC assays showed similar results. At 5 mg/mL, the fluid extract inhibited the AChE enzyme by (50.71 +/- 8.2)%. The ethyl acetate fraction exhibited the highest level of AChE inhibition, followed by the dichloromethane fraction. The isolated alkaloid uleine displayed an IC50 value of 0.45 microM.

  3. Increasing Arabian dust activity and the Indian summer monsoon

    NASA Astrophysics Data System (ADS)

    Solmon, F.; Nair, V. S.; Mallet, M.

    2015-07-01

    Over the past decade, aerosol optical depth (AOD) observations based on satellite and ground measurements have shown a significant increase over Arabia and the Arabian Sea, attributed to an intensification of regional dust activity. Recent studies have also suggested that west Asian dust forcing could induce a positive response of Indian monsoon precipitations on a weekly timescale. Using observations and a regional climate model including interactive slab-ocean and dust aerosol schemes, the present study investigates possible climatic links between the increasing June-July-August-September (JJAS) Arabian dust activity and precipitation trends over southern India during the 2000-2009 decade. Meteorological reanalysis and AOD observations suggest that the observed decadal increase of dust activity and a simultaneous intensification of summer precipitation trend over southern India are both linked to a deepening of JJAS surface pressure conditions over the Arabian Sea. In the first part of the study, we analyze the mean climate response to dust radiative forcing over the domain, discussing notably the relative role of Arabian vs. Indo-Pakistani dust regions. In the second part of the study, we show that the model skills in reproducing regional dynamical patterns and southern Indian precipitation trends are significantly improved only when an increasing dust emission trend is imposed on the basis of observations. We conclude that although interannual climate variability might primarily determine the observed regional pattern of increasing dust activity and precipitation during the 2000-2009 decade, the associated dust radiative forcing might in return induce a critical dynamical feedback contributing to enhancing regional moisture convergence and JJAS precipitations over southern India.

  4. Increased antitumor activity of tumor-specific peptide modified thymopentin.

    PubMed

    Lao, Xingzhen; Li, Bin; Liu, Meng; Chen, Jiao; Gao, Xiangdong; Zheng, Heng

    2014-12-01

    Thymopoietin pentapeptide (thymopentin, TP5), an immunomodulatory peptide, has been successfully used as an immune system enhancer for treating immune deficiency, cancer, and infectious diseases. However, poor penetration into tumors remains a key limitation to the efficacy and application of TP5. iRGD (CRGDK/RGPD/EC) has been introduced to certain anticancer agents, and increased specific tumor penetrability of drugs and cell internalization have been observed. In the present study, we fused this iRGD fragment with the C-terminal of TP5 to yield a new product, TP5-iRGD. Cell attachment assay showed that TP5-iRGD exhibits more extensive attachment to the melanoma cell line B16F10 than wild-type TP5. Tumor cell viability assay showed that iRGD conjugation with the TP5 C-terminus increases the basal antiproliferative activity of the pentapeptide against the melanoma cell line B16F10, the human lung cancer cell line H460, and the human breast cancer cell line MCF-7. Subsequent injections of TP5-iRGD inhibited in vivo melanoma progression more efficiently than the native TP5. Murine spleen lymphocyte proliferation assay also showed that TP5-iRGD and the parent pentapeptide feature nearly identical spleen lymphocyte proliferation activities. We built an integrin αvβ3 and TP5-iRGD computational binding model to investigate the mechanism by which TP5-iRGD promotes increased activity further. Conjugation with iRGD promotes binding to integrin αvβ3, thereby increasing the tumor-homing efficiency of the resultant peptide. These experimental and computational observations of increased TP5-iRGD activity help broaden the usage of TP5 and reflect the great application potential of the peptide as an anticancer agent.

  5. Neurotoxic responses in brain tissues of rainbow trout exposed to imidacloprid pesticide: Assessment of 8-hydroxy-2-deoxyguanosine activity, oxidative stress and acetylcholinesterase activity.

    PubMed

    Topal, Ahmet; Alak, Gonca; Ozkaraca, Mustafa; Yeltekin, Aslı Cilingir; Comaklı, Selim; Acıl, Gurdal; Kokturk, Mine; Atamanalp, Muhammed

    2017-05-01

    The extensive use of imidacloprid, a neonicotinoid insecticide, causes undesirable toxicity in non-targeted organisms including fish in aquatic environments. We investigated neurotoxic responses by observing 8-hydroxy-2-deoxyguanosine (8-OHdG) activity, oxidative stress and acetylcholinesterase (AChE) activity in rainbow trout brain tissue after 21 days of imidacloprid exposure at levels of (5 mg/L, 10 mg/L, 20 mg/L). The obtained results indicated that 8-OHdG activity did not change in fish exposed to 5 mg/L of imidacloprid, but 10 mg/L and 20 mg/L of imidacloprid significantly increased 8-OHdG activity compared to the control (p < 0.05). An immunopositiv reaction to 8-OHdG was detected in brain tissues. The brain tissues indicated a significant increase in antioxidant enzyme activities (superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)) compared to the control and there was a significant increase in malondialdehyde (MDA) levels (p < 0.05). High concentrations of imidacloprid caused a significant decrease in AChE enzyme activity (p < 0.05). These results suggested that imidacloprid can be neurotoxic to fish by promoting AChE inhibition, an increase in 8-OHdG activity and changes in oxidative stress parameters. Therefore, these data may reflect one of the molecular pathways that play a role in imidacloprid toxicity.

  6. Plant diversity increases soil microbial activity and soil carbon storage.

    PubMed

    Lange, Markus; Eisenhauer, Nico; Sierra, Carlos A; Bessler, Holger; Engels, Christoph; Griffiths, Robert I; Mellado-Vázquez, Perla G; Malik, Ashish A; Roy, Jacques; Scheu, Stefan; Steinbeiss, Sibylle; Thomson, Bruce C; Trumbore, Susan E; Gleixner, Gerd

    2015-04-07

    Plant diversity strongly influences ecosystem functions and services, such as soil carbon storage. However, the mechanisms underlying the positive plant diversity effects on soil carbon storage are poorly understood. We explored this relationship using long-term data from a grassland biodiversity experiment (The Jena Experiment) and radiocarbon ((14)C) modelling. Here we show that higher plant diversity increases rhizosphere carbon inputs into the microbial community resulting in both increased microbial activity and carbon storage. Increases in soil carbon were related to the enhanced accumulation of recently fixed carbon in high-diversity plots, while plant diversity had less pronounced effects on the decomposition rate of existing carbon. The present study shows that elevated carbon storage at high plant diversity is a direct function of the soil microbial community, indicating that the increase in carbon storage is mainly limited by the integration of new carbon into soil and less by the decomposition of existing soil carbon.

  7. Atomic insight into designed carbamate-based derivatives as acetylcholine esterase (AChE) inhibitors: a computational study by multiple molecular docking and molecular dynamics simulation.

    PubMed

    Mohammadi, Tecush; Ghayeb, Yousef

    2017-01-11

    Over 100 variants have been designed and studied, using multiple docking methods such as Autodock Vina, ArgusLab, Molegro Virtual Docker, and Hex-Cuda, to study the effect of alteration in the structure of carbamate-based acetylcholyne esterase (AChE) inhibitors. Sixteen selected systems were then subjected to 14 ns molecular dynamics (MD) simulations. Results from all the docking methods are in agreement. Variants that involved biphenyl substituents possess the most negative binding energies in the -37.64 to -39.31 kJ mol(-1) range due to their π-π interactions with AChE aromatic residues. The root mean square deviation values showed that all of these components achieved equilibration after 6 ns. Gyration radius (Rg) and solvent accessibility surface area were calculated to further investigate the AChE conformational changes in the presence of these components. MD simulation results suggested that these components might interact with AChE, possibly with no major changes in AChE secondary and tertiary structures.

  8. Active learning increases student performance in science, engineering, and mathematics.

    PubMed

    Freeman, Scott; Eddy, Sarah L; McDonough, Miles; Smith, Michelle K; Okoroafor, Nnadozie; Jordt, Hannah; Wenderoth, Mary Pat

    2014-06-10

    To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes--although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms.

  9. Active learning increases student performance in science, engineering, and mathematics

    PubMed Central

    Freeman, Scott; Eddy, Sarah L.; McDonough, Miles; Smith, Michelle K.; Okoroafor, Nnadozie; Jordt, Hannah; Wenderoth, Mary Pat

    2014-01-01

    To test the hypothesis that lecturing maximizes learning and course performance, we metaanalyzed 225 studies that reported data on examination scores or failure rates when comparing student performance in undergraduate science, technology, engineering, and mathematics (STEM) courses under traditional lecturing versus active learning. The effect sizes indicate that on average, student performance on examinations and concept inventories increased by 0.47 SDs under active learning (n = 158 studies), and that the odds ratio for failing was 1.95 under traditional lecturing (n = 67 studies). These results indicate that average examination scores improved by about 6% in active learning sections, and that students in classes with traditional lecturing were 1.5 times more likely to fail than were students in classes with active learning. Heterogeneity analyses indicated that both results hold across the STEM disciplines, that active learning increases scores on concept inventories more than on course examinations, and that active learning appears effective across all class sizes—although the greatest effects are in small (n ≤ 50) classes. Trim and fill analyses and fail-safe n calculations suggest that the results are not due to publication bias. The results also appear robust to variation in the methodological rigor of the included studies, based on the quality of controls over student quality and instructor identity. This is the largest and most comprehensive metaanalysis of undergraduate STEM education published to date. The results raise questions about the continued use of traditional lecturing as a control in research studies, and support active learning as the preferred, empirically validated teaching practice in regular classrooms. PMID:24821756

  10. Nicotine/Cigarette-smoke Promotes Metastasis of Pancreatic Cancer Through α7nAChR-mediated MUC4 Up-regulation

    PubMed Central

    Momi, Navneet; Ponnusamy, Moorthy P.; Kaur, Sukhwinder; Rachagani, Satyanarayana; Kunigal, Sateesh S; Chellappan, Srikumar; Ouellette, Michel M; Batra, Surinder K

    2012-01-01

    Despite evidence that long-term smoking is the leading risk factor for pancreatic malignancies, the underlying mechanism(s) for cigarette-smoke (CS)-induced pancreatic cancer (PC) pathogenesis has not been well-established. Our previous studies revealed an aberrant expression of the MUC4 mucin in PC as compared to the normal pancreas and its association with cancer progression and metastasis. Interestingly, here we explore a potential link between MUC4 expression and smoking-mediated PC pathogenesis and report that both cigarette-smoke-extract (CSE) and nicotine, which is the major component of CS, significantly up-regulates MUC4 in PC cells. This nicotine-mediated MUC4 overexpression was via α7 subunit of nicotinic acetylcholine receptor (nAChR) stimulation and subsequent activation of the JAK2/STAT3 downstream signaling cascade in cooperation with the MEK/ERK1/2 pathway; this effect was blocked by the α7nAChR antagonists, α-bungarotoxin and mecamylamine, and by specific siRNA-mediated STAT3 inhibition. Additionally, we demonstrated that nicotine-mediated MUC4 up-regulation promotes the PC cell migration through the activation of the downstream effectors such as HER2, c-Src and FAK; this effect was attenuated by shRNA-mediated MUC4 abrogation, further implying that these nicotine-mediated pathological effects on PC cells are MUC4 dependent. Furthermore, the in-vivo studies demonstrated a dramatic increase in the mean pancreatic tumor weight [low-dose (100 mg/m3 TSP), p=0.014; high-dose (247 mg/m3 TSP), p=0.02] and significant tumor metastasis to various distant organs in the CS-exposed-mice, orthotopically implanted with luciferase-transfected PC cells, as compared to the sham-controls. Moreover, the CS-exposed mice had elevated levels of serum cotinine [low-dose, 155.88±35.96 ng/ml; high-dose, 216.25±29.95 ng/ml] and increased MUC4, α7nAChR and pSTAT3 expression in the pancreatic tumor tissues. Altogether, our findings revealed for the first time that CS up

  11. Self-etching adhesives increase collagenolytic activity in radicular dentin.

    PubMed

    Tay, Franklin R; Pashley, David H; Loushine, Robert J; Weller, R Norman; Monticelli, Francesca; Osorio, Raquel

    2006-09-01

    Endogenous matrix metalloproteinases (MMPs) release from crown dentin and their activation results in degradation of hybrid layers created by dentin adhesives. This study tested the hypothesis that instrumented intraradicular dentin possesses latent collagenolytic activity that is activated by mild self-etching adhesives. Root dentin shavings were produced from 50 cleaned and shaped, saline-irrigated root canals using Gates Glidden drills and rinsed with sodium azide to prevent bacterial growth. Dried dentin powder aliquots were treated with two clinically-relevant MMP inhibitors, 2% chlorhexidine for 10 minutes and 17% EDTA for 1 minute. Additional dentin powder was mixed with Clearfil Liner Bond 2V or Clearfil Tri-S Bond for 1 minute followed by extracting the adhesives with acetone. Dentin powder was also treated with 2% chlorhexidine for 10 minutes before or after adhesive application. Collagenolytic activities of the nine groups were assayed with a fluorometer in 96-well plates, by recording the changes in fluorescence before and after addition of fluorescein-labeled type I collagen. Epoxy resin-embedded powders were examined with TEM for the extent of demineralization. Instrumented, mineralized intraradicular dentin possessed low but detectable collagenolytic activity that was inhibited by chlorhexidine (p < 0.001) and EDTA (p < 0.001). Both adhesives partially demineralized the dentin powder and activated latent MMPs, with 14- to 15-fold increases in collagenolytic activities (p < 0.001) that were significantly (p < 0.001) but incompletely inactivated after 10 min application of chlorhexidine. Mild self-etching adhesives activate latent MMPs without denaturing these enzymes, and may adversely affect the longevity of bonded root canal fillings and posts.

  12. Interactions Increase Forager Availability and Activity in Harvester Ants.

    PubMed

    Pless, Evlyn; Queirolo, Jovel; Pinter-Wollman, Noa; Crow, Sam; Allen, Kelsey; Mathur, Maya B; Gordon, Deborah M

    2015-01-01

    Social insect colonies use interactions among workers to regulate collective behavior. Harvester ant foragers interact in a chamber just inside the nest entrance, here called the 'entrance chamber'. Previous studies of the activation of foragers in red harvester ants show that an outgoing forager inside the nest experiences an increase in brief antennal contacts before it leaves the nest to forage. Here we compare the interaction rate experienced by foragers that left the nest and ants that did not. We found that ants in the entrance chamber that leave the nest to forage experienced more interactions than ants that descend to the deeper nest without foraging. Additionally, we found that the availability of foragers in the entrance chamber is associated with the rate of forager return. An increase in the rate of forager return leads to an increase in the rate at which ants descend to the deeper nest, which then stimulates more ants to ascend into the entrance chamber. Thus a higher rate of forager return leads to more available foragers in the entrance chamber. The highest density of interactions occurs near the nest entrance and the entrances of the tunnels from the entrance chamber to the deeper nest. Local interactions with returning foragers regulate both the activation of waiting foragers and the number of foragers available to be activated.

  13. Changes in baseball batters' brain activity with increased pitch choice.

    PubMed

    Ryu, Kwangmin; Kim, Jingu; Ali, Asif; Kim, Woojong; Radlo, Steven J

    2015-09-01

    In baseball, one factor necessary for batters to decide whether to swing or not depends on what type of pitch is thrown. Oftentimes batters will look for their pitch (i.e., waiting for a fastball). In general, when a pitcher has many types of pitches in his arsenal, batters will have greater difficulty deciding upon the pitch thrown. Little research has been investigated the psychophysiology of a batters decision-making processes. Therefore, the primary purpose of this study was to determine how brain activation changes according to an increase in the number of alternatives (NA) available. A total of 15 male college baseball players participated in this study. The stimuli used in this experiment were video clips of a right-handed pitcher throwing fastball, curve, and slider pitches. The task was to press a button after selecting the fastball as the target stimulus from two pitch choices (fastball and curve), and then from three possibilities (fastball, curve, and slider). Functional and anatomic image scanning magnetic resonance imaging (MRI) runs took 4 and 5[Formula: see text]min, respectively. According to our analysis, the right precentral gyrus, left medial frontal gyrus, and right fusiform gyrus were activated when the NA was one. The supplementary motor areas (SMA) and primary motor cortex were activated when there were two alternatives to choose from and the inferior orbitofrontal gyrus was specifically activated with three alternatives. Contrary to our expectations, the NA was not a critical factor influencing the activation of related decision making areas when the NA was compared against one another. These findings highlight that specific brain areas related to decision making were activated as the NA increased.

  14. Projecting climate-driven increases in North American fire activity

    NASA Astrophysics Data System (ADS)

    Wang, D.; Morton, D. C.; Collatz, G. J.

    2013-12-01

    Climate regulates fire activity through controls on vegetation productivity (fuels), lightning ignitions, and conditions governing fire spread. In many regions of the world, human management also influences the timing, duration, and extent of fire activity. These coupled interactions between human and natural systems make fire a complex component of the Earth system. Satellite data provide valuable information on the spatial and temporal dynamics of recent fire activity, as active fires, burned area, and land cover information can be combined to separate wildfires from intentional burning for agriculture and forestry. Here, we combined satellite-derived burned area data with land cover and climate data to assess fire-climate relationships in North America between 2000-2012. We used the latest versions of the Global Fire Emissions Database (GFED) burned area product and Modern-Era Retrospective Analysis for Research and Applications (MERRA) climate data to develop regional relationships between burned area and potential evaporation (PE), an integrated dryness metric. Logistic regression models were developed to link burned area with PE and individual climate variables during and preceding the fire season, and optimal models were selected based on Akaike Information Criterion (AIC). Overall, our model explained 85% of the variance in burned area since 2000 across North America. Fire-climate relationships from the era of satellite observations provide a blueprint for potential changes in fire activity under scenarios of climate change. We used that blueprint to evaluate potential changes in fire activity over the next 50 years based on twenty models from the Coupled Model Intercomparison Project Phase 5 (CMIP5). All models suggest an increase of PE under low and high emissions scenarios (Representative Concentration Pathways (RCP) 4.5 and 8.5, respectively), with largest increases in projected burned area across the western US and central Canada. Overall, near

  15. Tetrahydrohyperforin decreases cholinergic markers associated with amyloid-β plaques, 4-hydroxynonenal formation, and caspase-3 activation in AβPP/PS1 mice.

    PubMed

    Carvajal, Francisco J; Zolezzi, Juan M; Tapia-Rojas, Cheril; Godoy, Juan A; Inestrosa, Nibaldo C

    2013-01-01

    Alzheimer's disease (AD) is a neurodegenerative disorder characterized by a progressive deterioration of cognitive abilities, amyloid-β peptide (Aβ) accumulation, neurofibrillary tangle deposition, synaptic alterations, and oxidative injury. In AD patients, acetylcholinesterase (AChE) activity is low in most regions of the brain, but increased within and around amyloid plaques, where it accelerates the Aβ assembly into oligomers and fibrils, increasing its neurotoxicity. Tetrahydrohyperforin (THH), a semi-synthetic derivative of hyperforin, reduces tau phosphorylation and Aβ accumulation in AD mouse models. In the present study, we examined the effects of THH on Aβ-AChE complexes, α7-nicotinic acetylcholine receptors (α7-nAChR), 4-hydroxynonenal (4-HNE) adducts, caspase-3 activation, and spatial memory in young AβPPSwe/PSEN1ΔE9 (AβPP/PS1) transgenic mice, in order to evaluate its potential preventive effects on the development of the disease. We report here that treatment with THH prevents the association of AChE to different types of amyloid plaques; partially restores the brain distribution of AChE molecular forms; increases α7-nAChR levels in the hippocampus of treated mice; decreases the amount of these receptors in amyloid plaques; and reduces the oxidative damage, evidenced by 4-HNE adduct formation and caspase-3 activation on AβPP/PS1 mice brain; demonstrating the neuroprotective properties of THH. Finally, we found that the acute treatment of hippocampal neurons with THH, in the presence of Aβ-AChE complexes, prevents 4-HNE adduct formation and caspase-3 activation. Our data support a therapeutic potential of THH for the treatment of AD.

  16. Serotonin increases synaptic activity in olfactory bulb glomeruli.

    PubMed

    Brill, Julia; Shao, Zuoyi; Puche, Adam C; Wachowiak, Matt; Shipley, Michael T

    2016-03-01

    Serotoninergic fibers densely innervate olfactory bulb glomeruli, the first sites of synaptic integration in the olfactory system. Acting through 5HT2A receptors, serotonin (5HT) directly excites external tufted cells (ETCs), key excitatory glomerular neurons, and depolarizes some mitral cells (MCs), the olfactory bulb's main output neurons. We further investigated 5HT action on MCs and determined its effects on the two major classes of glomerular interneurons: GABAergic/dopaminergic short axon cells (SACs) and GABAergic periglomerular cells (PGCs). In SACs, 5HT evoked a depolarizing current mediated by 5HT2C receptors but did not significantly impact spike rate. 5HT had no measurable direct effect in PGCs. Serotonin increased spontaneous excitatory and inhibitory postsynaptic currents (sEPSCs and sIPSCs) in PGCs and SACs. Increased sEPSCs were mediated by 5HT2A receptors, suggesting that they are primarily due to enhanced excitatory drive from ETCs. Increased sIPSCs resulted from elevated excitatory drive onto GABAergic interneurons and augmented GABA release from SACs. Serotonin-mediated GABA release from SACs was action potential independent and significantly increased miniature IPSC frequency in glomerular neurons. When focally applied to a glomerulus, 5HT increased MC spontaneous firing greater than twofold but did not increase olfactory nerve-evoked responses. Taken together, 5HT modulates glomerular network activity in several ways: 1) it increases ETC-mediated feed-forward excitation onto MCs, SACs, and PGCs; 2) it increases inhibition of glomerular interneurons; 3) it directly triggers action potential-independent GABA release from SACs; and 4) these network actions increase spontaneous MC firing without enhancing responses to suprathreshold sensory input. This may enhance MC sensitivity while maintaining dynamic range.

  17. Nicotine-Induced Effects on Nicotinic Acetylcholine Receptors (nAChRs), Ca2+ and Brain-Derived Neurotrophic Factor (BDNF) in STC-1 Cells

    PubMed Central

    Qian, Jie; Mummalaneni, Shobha K.; Alkahtani, Reem M.; Mahavadi, Sunila; Murthy, Karnam S.; Grider, John R.

    2016-01-01

    In addition to the T2R bitter taste receptors, neuronal nicotinic acetylcholine receptors (nAChRs) have recently been shown to be involved in the bitter taste transduction of nicotine, acetylcholine and ethanol. However, at present it is not clear if nAChRs are expressed in enteroendocrine cells other than beta cells of the pancreas and enterochromaffin cells, and if they play a role in the synthesis and release of neurohumoral peptides. Accordingly, we investigated the expression and functional role of nAChRs in enteroendocrine STC-1 cells. Our studies using RT-PCR, qRT-PCR, immunohistochemical and Western blotting techniques demonstrate that STC-1 cells express several α and β nAChR subunits. Exposing STC-1 cells to nicotine acutely (24h) or chronically (4 days) induced a differential increase in the expression of nAChR subunit mRNA and protein in a dose- and time-dependent fashion. Mecamylamine, a non-selective antagonist of nAChRs, inhibited the nicotine-induced increase in mRNA expression of nAChRs. Exposing STC-1 cells to nicotine increased intracellular Ca2+ in a dose-dependent manner that was inhibited in the presence of mecamylamine or dihydro-β-erythroidine, a α4β2 nAChR antagonist. Brain-derived neurotrophic factor (BDNF) mRNA and protein were detected in STC-1 cells using RT-PCR, specific BDNF antibody, and enzyme-linked immunosorbent assay. Acute nicotine exposure (30 min) decreased the cellular content of BDNF in STC-1 cells. The nicotine-induced decrease in BDNF was inhibited in the presence of mecamylamine. We also detected α3 and β4 mRNA in intestinal mucosal cells and α3 protein expression in intestinal enteroendocrine cells. We conclude that STC-1 cells and intestinal enteroendocrine cells express nAChRs. In STC-1 cells nAChR expression is modulated by exposure to nicotine in a dose- and time-dependent manner. Nicotine interacts with nAChRs and inhibits BDNF expression in STC-1 cells. PMID:27846263

  18. Increased AICD generation does not result in increased nuclear translocation or activation of target gene transcription

    SciTech Connect

    Waldron, Elaine; Isbert, Simone; Kern, Andreas; Jaeger, Sebastian; Martin, Anne M.; Hebert, Sebastien S.; Behl, Christian; Weggen, Sascha; De Strooper, Bart; Pietrzik, Claus U.

    2008-08-01

    A sequence of amyloid precursor protein (APP) cleavages culminates in the sequential release of the APP intracellular domain (AICD) and the amyloid {beta} peptide (A{beta}) and/or p3 fragment. One of the environmental factors favouring the accumulation of AICD appears to be a rise in intracellular pH. Here we further identified the metabolism and subcellular localization of artificially expressed constructs under such conditions. We also co-examined the mechanistic lead up to the AICD accumulation and explored possible significances for its increased expression. We found that most of the AICD generated under pH neutralized conditions is likely cleaved from C83. While the AICD surplus was unable to further activate transcription of a luciferase reporter via a Gal4-DNA-binding domain, it failed entirely via the endogenous promoter regions of proposed target genes, APP and KAI1. The lack of a specific transactivation potential was also demonstrated by the unchanged levels of target gene mRNA. However, rather than translocating to the nucleus, the AICD surplus remains membrane tethered or free in the cytosol where it interacts with Fe65. Therefore we provide strong evidence that an increase in AICD generation does not directly promote gene activation of previously proposed target 0011gen.

  19. A ketogenic diet increases succinic dehydrogenase activity in aging cardiomyocytes.

    PubMed

    Balietti, Marta; Fattoretti, Patrizia; Giorgetti, Belinda; Casoli, Tiziana; Di Stefano, Giuseppina; Solazzi, Moreno; Platano, Daniela; Aicardi, Giorgio; Bertoni-Freddari, Carlo

    2009-08-01

    Impairment of energy metabolism and an increase of reactive oxygen species (ROS) production seem to play a major role in age-related apoptotic loss of cardiomyocytes. Succinic dehydrogenase (SDH) is an important marker of the mitochondrial capability to provide an adequate amount of ATP. Moreover, because of its unique redox properties, SDH activity contributes to maintain the reduced state of the ubiquinone pool. Recent reports have shown that ketone body intake improves cardiac metabolic efficiency and exerts a cardioprotective antioxidant action, we therefore performed a cytochemical investigation of SDH activity in cardiomyocytes of late-adult (19-month-old) rats fed for 8 weeks with a medium-chain triglycerides ketogenic diet (MCT-KD). Young, age-matched and old animals fed with a standard chow were used as controls. The overall area of the precipitates (PA) from SDH activity and the area of the SDH-positive mitochondria (MA) were measured. The percent ratios PA/MA and MA/total myocardial tissue area (MA/TA) were the parameters taken into account. We found that PA/MA was significantly higher in young control rats and in MCT-KD-fed rats versus late-adult and old control rats and in young control versus MCT-KD-fed rats. MA/TA of MCT-KD-fed rats was significantly higher versus age-matched and old control rats and tended to be higher versus young control rats; this parameter was significantly higher in young versus old control rats. Thus, MCT-KD intake partially recovers age-related decrease of SDH activity and increases the myocardial area occupied by metabolically active mitochondria. These effects might counteract metabolic alterations leading to apoptosis-induced myocardial atrophy and failure during aging.

  20. Effect of the Heat-exposure on Peripheral Sudomotor Activity Including the Density of Active Sweat Glands and Single Sweat Gland Output.

    PubMed

    Lee, Jeong-Beom; Kim, Tae-Wook; Shin, Young-Oh; Min, Young-Ki; Yang, Hun-Mo

    2010-10-01

    Tropical inhabitants are able to tolerate heat through permanent residence in hot and often humid tropical climates. The goal of this study was to clarify the peripheral mechanisms involved in thermal sweating pre and post exposure (heat-acclimatization over 10 days) by studying the sweating responses to acetylcholine (ACh), a primary neurotransmitter of sudomotor activity, in healthy subjects (n=12). Ten percent ACh was administered on the inner forearm skin for iontophoresis. Quantitative sudomotor axon reflex testing, after iontophoresis (2 mA for 5 min) with ACH, was performed to determine directly activated (DIR) and axon reflex-mediated (AXR) sweating during ACh iontophoresis. The sweat rate, activated sweat gland density, sweat gland output per single gland activated, as well as oral and skin temperature changes were measured. The post exposure activity had a short onset time (p<0.01), higher active sweat rate [(AXR (p<0.001) and DIR (p<0.001)], higher sweat output per gland (p<0.001) and higher transepidermal water loss (p<0.001) compared to the pre-exposure measurements. The activated sweat rate in the sudomotor activity increased the output for post-exposure compared to the pre-exposure measurements. The results suggested that post-exposure activity showed a higher active sweat gland output due to the combination of a higher AXR (DIR) sweat rate and a shorter onset time. Therefore, higher sudomotor responses to ACh receptors indicate accelerated sympathetic nerve responsiveness to ACh sensitivity by exposure to environmental conditions.

  1. Betaine increases the butyrylcholinesterase activity in rat plasma.

    PubMed

    Šišková, K; Dubničková, M; Pašková, Ľ; Rajdl, D; Ďuračková, Z; Muchová, J; Pauliková, I; Racek, J

    2016-01-01

    The physiological function of butyrylcholinesterase (EC 3.1.1.8, BChE) is not clearly understood, but a role was suggested in the fat utilization process, resulting in positive correlation between plasma triglyceride (TG) levels and BChE activity. Consequently we tested the hypothesis that regular intake of betaine, a natural compound intervening in the liver TG metabolism could influence the BChE activity. The BChE activity was estimated spectrophotometrically in plasma of rats fed with betaine enriched standard (B) or high-fat diet (HFB). The results confirmed decreased TG plasma levels after betaine treatment independently on the type of diet (0.15+/-0.03 (B) vs. 0.27+/-0.08 (control) mmol/l; p=0.003 and 0.13+/-0.03 (HFB) vs. 0.27+/-0.08 (control) mmol/l; p=0.005). The BChE activity increased significantly with betaine administration, however the change was more distinct in the HFB group (0.84+/-0.34 (HFB) vs. 0.22+/-0.04 (control) O.D./min/mg; p<0.001 and 0.41+/-0.11 (B) vs. 0.22+/-0.04 (control) O.D./min/mg; p=0.001). In conclusion, betaine intake led to elevated BChE activity in plasma and this effect was potentiated by the HF diet. Since betaine is in general used as a supplement in the treatment of liver diseases accompanied by TG overload, its impact on the BChE activity in the role of the liver function marker should be taken into account.

  2. Nicotine regulates activity of lateral habenula neurons via presynaptic and postsynaptic mechanisms

    PubMed Central

    Zuo, Wanhong; Xiao, Cheng; Gao, Ming; Hopf, F. Woodward; Krnjević, Krešimir; McIntosh, J. Michael; Fu, Rao; Wu, Jie; Bekker, Alex; Ye, Jiang-Hong

    2016-01-01

    There is much interest in brain regions that drive nicotine intake in smokers. Interestingly, both the rewarding and aversive effects of nicotine are probably critical for sustaining nicotine addiction. The medial and lateral habenular (LHb) nuclei play important roles in processing aversion, and recent work has focused on the critical involvement of the LHb in encoding and responding to aversive stimuli. Several neurotransmitter systems are implicated in nicotine’s actions, but very little is known about how nicotinic acetylcholine receptors (nAChRs) regulate LHb activity. Here we report in brain slices that activation of nAChRs depolarizes LHb cells and robustly increases firing, and also potentiates glutamate release in LHb. These effects were blocked by selective antagonists of α6-containing (α6*) nAChRs, and were absent in α6*-nAChR knockout mice. In addition, nicotine activates GABAergic inputs to LHb via α4β2-nAChRs, at lower concentrations but with more rapid desensitization relative to α6*-nAChRs. These results demonstrate the existence of diverse functional nAChR subtypes at presynaptic and postsynaptic sites in LHb, through which nicotine could facilitate or inhibit LHb neuronal activity and thus contribute to nicotine aversion or reward. PMID:27596561

  3. Obstruction increases activation in the right inferior frontal gyrus.

    PubMed

    Liu, Tao; Saito, Hirofumi; Oi, Misato

    2016-01-01

    The right inferior frontal gyrus (IFG) is involved in intention understanding during interpersonal interactions. To examine how prior experience of cooperation and competition affects one's right IFG activation in the subsequent interaction, using near-infrared spectroscopy (NIRS) we simultaneously measured paired participants' bilateral IFG activations during a turn-taking game. Participant pairs were assigned to either one of two roles: a Builder taking the initial move to copy a target disk-pattern on monitor and the Partner taking the second move to aid in (cooperation) or to obstruct (competition) the Builder. The experiment consisted of two sessions. One participant (B-P) played as a Builder (B-) in session 1 and changed the role to the Partner (-P) in session 2, and vice versa for the paired participant (P-B). NIRS data in competition demonstrated that the Builder (B-) being obstructed in session 1 showed higher right IFG activation when (s)he took a role of obstructor (-P) in session 2 (the obstructed effect), whereas "the cooperated effect" was not revealed in cooperation. These results suggest that prior experience of being obstructed may facilitate understanding of the Builder and/or the obstructor's tactical move, thereby increasing his/her right IFG activation when one is meant to obstruct in subsequent competitions.

  4. Fluorescence Quenching Determination of Uranium (VI) Binding Properties by Two Functional Proteins: Acetylcholinesterase (AChE) and Vitellogenin (Vtg).

    PubMed

    Coppin, Frédéric; Michon, Jérôme; Garnier, Cédric; Frelon, Sandrine

    2015-05-01

    The interactions between uranium and two functional proteins (AChE and Vtg) were investigated using fluorescence quenching measurements. The combined use of a microplate spectrofluorometer and logarithmic additions of uranium into protein solutions allowed us to define the fluorescence quenching over a wide range of [U]/[Pi] ratios (from 1 to 3235) at physiologically relevant conditions of pH. Results showed that fluorescence from the two functional proteins was quenched by UO2 (2+). Stoichiometry reactions, fluorescence quenching mechanisms and complexing properties of proteins, i.e. binding constants and binding sites densities, were determined using classic fluorescence quenching methods and curve-fitting software (PROSECE). It was demonstrated that in our test conditions, the protein complexation by uranium could be simulated by two specific sites (L1 and L2). The obtained complexation constant values are log K1 = 5.7 (±1.0), log K2 = 4.9 (±1.1); L1 = 83 (±2), L2 = 2220 (±150) for U(VI) - Vtg and log K1 = 8.1 (±0.9), log K2 = 6.6 (±0.5), L1 = 115 (±16), L2 = 530 (±23) for U(VI)-AChE (Li is expressed in mol/mol of protein).

  5. Both novelty and expertise increase action observation network activity

    PubMed Central

    Liew, Sook-Lei; Sheng, Tong; Margetis, John L.; Aziz-Zadeh, Lisa

    2013-01-01

    Our experiences with others affect how we perceive their actions. In particular, activity in bilateral premotor and parietal cortices during action observation, collectively known as the action observation network (AON), is modulated by one's expertise with the observed actions or individuals. However, conflicting reports suggest that AON activity is greatest both for familiar and unfamiliar actions. The current study examines the effects of different types and amounts of experience (e.g., visual, interpersonal, personal) on AON activation. fMRI was used to scan 16 healthy participants without prior experience with individuals with amputations (novices), 11 experienced occupational therapists (OTs) who had varying amounts of experience with individuals with amputations, and one individual born with below-elbow residual limbs (participant CJ), as they viewed video clips of goal-matched actions performed by an individual with residual limbs and by an individual with hands. Participants were given increased visual exposure to actions performed by both effectors midway through the scanning procedure. Novices demonstrated a large AON response to the initial viewing of an individual with residual limbs compared to one with hands, but this signal was attenuated after they received visual exposure to both effectors. In contrast, OTs, who had moderate familiarity with residual limbs, demonstrated a lower AON response upon initial viewing—similar to novices after they received visual exposure. At the other extreme, CJ, who has extreme familiarity with residual limbs both visually and motorically, shows a largely increased left-lateralized AON response, exceeding that of novices and experienced OTs, when viewing the residual limb compared to hand actions. These results suggest that a nuanced model of AON engagement is needed to explain how cases of both extreme experience (CJ) and extreme novelty (novices) can result in the greatest AON activity. PMID:24062656

  6. Flavone deglycosylation increases their anti-inflammatory activity and absorption

    PubMed Central

    Hostetler, Gregory; Riedl, Ken; Cardenas, Horacio; Diosa-Toro, Mayra; Arango, Daniel; Schwartz, Steven; Doseff, Andrea I.

    2014-01-01

    Scope Flavones have reported anti-inflammatory activities, but the ability of flavone-rich foods to reduce inflammation is unclear. Here, we report the effect of flavone glycosylation in the regulation of inflammatory mediators in vitro and the absorption of dietary flavones in vivo. Methods and results The anti-inflammatory activities of celery extracts, some rich in flavone aglycones and others rich in flavone glycosides, were tested on the inflammatory mediators tumor necrosis factor α (TNF-α) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in lipopolysaccharide-stimulated macrophages. Pure flavone aglycones and aglycone-rich extracts effectively reduced TNF-α production and inhibited the transcriptional activity of NF-κB, while glycoside-rich extracts showed no significant effects. Deglycosylation of flavones increased cellular uptake and cytoplasmic localization as shown by high-performance liquid chromatography (HPLC) and microscopy using the flavonoid fluorescent dye diphenyl-boric acid 2-aminoethyl ester (DPBA). Celery diets with different glycoside or aglycone contents were formulated and absorption was evaluated in mice fed with 5 or 10% celery diets. Relative absorption in vivo was significantly higher in mice fed with aglycone-rich diets as determined by HPLC-MS/MS (where MS/MS is tandem mass spectrometry). Conclusion These results demonstrate that deglycosylation increases absorption of dietary flavones in vivo and modulates inflammation by reducing TNF-α and NF-κB, suggesting the potential use of functional foods rich in flavones for the treatment and prevention of inflammatory diseases. PMID:22351119

  7. Visible-light-activated photoelectrochemical biosensor for the study of acetylcholinesterase inhibition induced by endogenous neurotoxins.

    PubMed

    Huang, Qilin; Chen, Hua; Xu, Lili; Lu, Danqin; Tang, Linlin; Jin, Litong; Xu, Zhiai; Zhang, Wen

    2013-07-15

    In this report, a novel visible-light-activated photoelectrochemical biosensor was fabricated to study the inhibition of acetylcholinesterase (AChE) activity induced by two endogenous neurotoxins, 1(R)-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline [(R)-Sal] and 1(R),2(N)-dimethyl-6,7-dihydroxy-1,2,3,4-tetra-hydroisoquinoline [(R)-NMSal], which have drawn much attention in the study of the pathogenesis of neurodegenerative diseases such as Parkinson's disease. The photoelectrode was prepared by three steps, as follows. At first, nitrogen and fluorine co-doped TiO2 nanotubes (TNs) were obtained by anodic oxidation of a Ti sheet. Secondly, silver nanoparticles (AgNPs) were deposited onto the TNs through a microwave-assisted heating polyol (MAHP) process. At last, AChE was immobilized on the obtained photoelectrode and the biosensor was marked as AChE/Ag/NFTNs. Due to the nitrogen and fluorine co-doping, the photoelectrochemical biosensors can produce high photocurrent under visible light irradiation. Moreover, the presence of AgNPs greatly increased the photocurrent response of the biosensor. AChE/Ag/NFTNs hybrid system was used to study AChE inhibition induced by (R)-Sal and (R)-NMSal. The result proved that both (R)-Sal and (R)-NMSal exhibited mixed and reversible inhibition against AChE. This strategy is of great significance for the development of novel photoelectrochemical biosensors in the future.

  8. [Increased fibrinolytic activity during cardiopulmonary bypass is caused by activated protein C system].

    PubMed

    Gando, S; Tedo, I; Masio, H; Goda, Y; Kawahigashi, H

    1994-06-01

    To examine the hypothesis that activated protein C system during cardiopulmonary bypass surgery may increase fibrinolytic activity during cardiopulmonary bypass, protein C activity, protein C antigen and thrombomodulin of sixteen patients undergoing elective cardiopulmonary bypass surgery were investigated after induction of anesthesia, before and after cardiopulmonary bypass, and at the end of operation. Protein C activity decreased and thrombomodulin increased significantly after the cardiopulmonary bypass. There were no significant correlations of thrombomodulin with protein C activity and protein C antigen. In conclusion, we have demonstrated that protein C system is activated and circulating thrombomodulin appears in the systemic circulation during cardiopulmonary bypass surgery and this enhanced activation of protein C system is possibly related to the reported increase of fibrinolytic activity during cardiopulmonary bypass.

  9. Dopamine Receptor Activation Increases HIV Entry into Primary Human Macrophages

    PubMed Central

    Gaskill, Peter J.; Yano, Hideaki H.; Kalpana, Ganjam V.; Javitch, Jonathan A.; Berman, Joan W.

    2014-01-01

    Macrophages are the primary cell type infected with HIV in the central nervous system, and infection of these cells is a major component in the development of neuropathogenesis and HIV-associated neurocognitive disorders. Within the brains of drug abusers, macrophages are exposed to increased levels of dopamine, a neurotransmitter that mediates the addictive and reinforcing effects of drugs of abuse such as cocaine and methamphetamine. In this study we examined the effects of dopamine on HIV entry into primary human macrophages. Exposure to dopamine during infection increased the entry of R5 tropic HIV into macrophages, irrespective of the concentration of the viral inoculum. The entry pathway affected was CCR5 dependent, as antagonizing CCR5 with the small molecule inhibitor TAK779 completely blocked entry. The effect was dose-dependent and had a steep threshold, only occurring above 108 M dopamine. The dopamine-mediated increase in entry required dopamine receptor activation, as it was abrogated by the pan-dopamine receptor antagonist flupenthixol, and could be mediated through both subtypes of dopamine receptors. These findings indicate that the effects of dopamine on macrophages may have a significant impact on HIV pathogenesis. They also suggest that drug-induced increases in CNS dopamine may be a common mechanism by which drugs of abuse with distinct modes of action exacerbate neuroinflammation and contribute to HIV-associated neurocognitive disorders in infected drug abusers. PMID:25268786

  10. Increased serum cortisol binding in chronic active hepatitis

    SciTech Connect

    Orbach, O.; Schussler, G.C.

    1989-01-01

    A high serum cortisol concentration, apparently due to increased cortisol-binding globulin (CBG), was found in a patient (index case) with chronic active hepatitis (CAH). We therefore performed further studies to determine whether increased cortisol binding is generally associated with CAH. Serum samples were obtained from 15 hospitalized patients with long-term liver function test elevations but no evidence of cirrhosis, 15 normal subjects without a history of hepatitis, four healthy pregnant women, and 10 alcoholic patients with stigmata of cirrhosis. Serum cortisol binding was measured by an adaptation of a previously described charcoal uptake method. Thyroxine-binding globulin (TBG) and sex hormone-binding globulin were determined by radioimmunoassays. Charcoal uptake of 125I cortisol from sera of normal subjects and additional patients with CAH revealed that increased serum cortisol binding by a saturable site, presumably CBG, was associated with CAH. Cortisol binding was significantly correlated with immunoassayable TBG, suggesting that in CAH, similar mechanisms may be responsible for increasing the serum concentrations of CBG and TBG.

  11. Pharmacological characterization of RS-1259, an orally active dual inhibitor of acetylcholinesterase and serotonin transporter, in rodents: possible treatment of Alzheimer's disease.

    PubMed

    Abe, Yasuyuki; Aoyagi, Atsushi; Hara, Takao; Abe, Kazumi; Yamazaki, Reina; Kumagae, Yoshihiro; Naruto, Shunji; Koyama, Kazuo; Marumoto, Shinji; Tago, Keiko; Toda, Narihiro; Takami, Kazuko; Yamada, Naho; Ori, Mayuko; Kogen, Hiroshi; Kaneko, Tsugio

    2003-09-01

    A dual inhibitor of acetylcholinesterase (AChE) and serotonin transporter (SERT), RS-1259 (4-[1S)-methylamino-3-(4-nitrophenoxy)]propylphenyl N,N-dimethylcarbamate (fumaric acid)(1/2)salt), was newly synthesized. RS-1259 simultaneously inhibited AChE and SERT in the brain following an oral administration in mice and rats. Actual simultaneous elevation of extracellular levels of 5-HT and ACh in the rat hippocampus was confirmed by microdialysis. The compound was as effective as SERT inhibitors such as fluoxetine and fluvoxamine in a 5-hydroxytryptophan-enhancing test in mice. Spatial memory deficits in the two-platform task of a water maze in aged rats were ameliorated by RS-1259 as well as donepezil. Both RS-1259 and donepezil increased the awake episodes in the daytime electroencephalogram of rats. Although RS-1259 was weaker than donepezil in enhancing central cholinergic transmission, as observed by ACh elevation in the hippocampus and memory enhancement in aged rats, the efficacy of RS-1259 on the consciousness level, which reflects the whole activity in the brain, was almost the same as that of donepezil. These results suggest that both cholinergic and serotonergic systems are involved in maintaining brain arousal and that a dual inhibitor of AChE and SERT may be useful for the treatment of cognitive disorders associated with reduced brain activity such as in Alzheimer's disease.

  12. Cytokinin activity increases stomatal density and transpiration rate in tomato

    PubMed Central

    Farber, Mika; Attia, Ziv; Weiss, David

    2016-01-01

    Previous studies on cytokinin (CK) and drought have suggested that the hormone has positive and negative effects on plant adaptation to restrictive conditions. This study examined the effect of CK on transpiration, stomatal activity, and response to drought in tomato (Solanum lycopersicum) plants. Transgenic tomato plants overexpressing the Arabidopsis thaliana CK-degrading enzyme CK oxidase/dehydrogenase 3 (CKX3) maintained higher leaf water status under drought conditions due to reduced whole-plant transpiration. The reduced transpiration could be attributed to smaller leaf area and reduced stomatal density. CKX3-overexpressing plants contained fewer and larger pavement cells and fewer stomata per leaf area than wild-type plants. In addition, wild-type leaves treated with CK exhibited enhanced transpiration and had more pavement cells and increased numbers of stomata per leaf area than untreated leaves. Manipulation of CK levels did not affect stomatal movement or abscisic acid-induced stomatal closure. Moreover, we found no correlation between stomatal aperture and the activity of the CK-induced promoter Two-Component Signaling Sensor (TCS) in guard cells. Previous studies have shown that drought reduces CK levels, and we propose this to be a mechanism of adaptation to water deficiency: the reduced CK levels suppress growth and reduce stomatal density, both of which reduce transpiration, thereby increasing tolerance to prolonged drought conditions. PMID:27811005

  13. Prescribed Active Learning Increases Performance in Introductory Biology

    PubMed Central

    O'Connor, Eileen; Parks, John W.; Cunningham, Matthew; Hurley, David; Haak, David; Dirks, Clarissa; Wenderoth, Mary Pat

    2007-01-01

    We tested five course designs that varied in the structure of daily and weekly active-learning exercises in an attempt to lower the traditionally high failure rate in a gateway course for biology majors. Students were given daily multiple-choice questions and answered with electronic response devices (clickers) or cards. Card responses were ungraded; clicker responses were graded for right/wrong answers or participation. Weekly practice exams were done as an individual or as part of a study group. Compared with previous versions of the same course taught by the same instructor, students in the new course designs performed better: There were significantly lower failure rates, higher total exam points, and higher scores on an identical midterm. Attendance was higher in the clicker versus cards section; attendance and course grade were positively correlated. Students did better on clicker questions if they were graded for right/wrong answers versus participation, although this improvement did not translate into increased scores on exams. In this course, achievement increases when students get regular practice via prescribed (graded) active-learning exercises. PMID:17548875

  14. Obesity-induced increases in sympathetic nerve activity: sex matters.

    PubMed

    Brooks, Virginia L; Shi, Zhigang; Holwerda, Seth W; Fadel, Paul J

    2015-01-01

    Abundant evidence obtained largely from male human and animal subjects indicates that obesity increases sympathetic nerve activity (SNA), which contributes to hypertension development. However, recent studies that included women reported that the strong relationships between muscle SNA and waist circumference or body mass index (BMI) found in men are not present in overweight and obese women. A similar sex difference in the association between adiposity and hypertension development has been identified in animal models of obesity. In this brief review, we consider two possible mechanisms for this sex difference. First, visceral adiposity, leptin, insulin, and angiotensin II have been identified as potential culprits in obesity-induced sympathoexcitation in males. We explore if these factors wield the same impact in females. Second, we consider if sex differences in vascular reactivity to sympathetic activation contribute. Our survey of the literature suggests that premenopausal females may be able to resist obesity-induced sympathoexcitation and hypertension in part due to differences in adipose disposition as well as its muted inflammatory response and reduced production of pressor versus depressor components of the renin-angiotensin system. In addition, vascular responsiveness to increased SNA may be reduced. However, more importantly, we identify the urgent need for further study, not only of sex differences per se, but also of the mechanisms that may mediate these differences. This information is required not only to refine treatment options for obese premenopausal women but also to potentially reveal new therapeutic avenues in obese men and women.

  15. Cytokinin activity increases stomatal density and transpiration rate in tomato.

    PubMed

    Farber, Mika; Attia, Ziv; Weiss, David

    2016-12-01

    Previous studies on cytokinin (CK) and drought have suggested that the hormone has positive and negative effects on plant adaptation to restrictive conditions. This study examined the effect of CK on transpiration, stomatal activity, and response to drought in tomato (Solanum lycopersicum) plants. Transgenic tomato plants overexpressing the Arabidopsis thaliana CK-degrading enzyme CK oxidase/dehydrogenase 3 (CKX3) maintained higher leaf water status under drought conditions due to reduced whole-plant transpiration. The reduced transpiration could be attributed to smaller leaf area and reduced stomatal density. CKX3-overexpressing plants contained fewer and larger pavement cells and fewer stomata per leaf area than wild-type plants. In addition, wild-type leaves treated with CK exhibited enhanced transpiration and had more pavement cells and increased numbers of stomata per leaf area than untreated leaves. Manipulation of CK levels did not affect stomatal movement or abscisic acid-induced stomatal closure. Moreover, we found no correlation between stomatal aperture and the activity of the CK-induced promoter Two-Component Signaling Sensor (TCS) in guard cells. Previous studies have shown that drought reduces CK levels, and we propose this to be a mechanism of adaptation to water deficiency: the reduced CK levels suppress growth and reduce stomatal density, both of which reduce transpiration, thereby increasing tolerance to prolonged drought conditions.

  16. Geometric complexity is increased in in vitro activated platelets.

    PubMed

    Bianciardi, Giorgio

    2015-06-01

    This article investigates the use of computerized fractal analysis for objective characterization of the complexity of platelets in vitro stimulated by low level thrombin (0.02 U mL(-1) ), collected from healthy individuals and observed by means of transmission electron microscopy. Platelet boundaries were extracted by means of automatically image analysis. Local fractal dimension was evaluated by the box-counting technique (measure of geometric complexity of the platelet outline). The results showed that the platelet boundary is fractal when observed by transmission electron microscopy and that, after an in vitro platelet activation test, the shape of platelets present increased geometric complexity in comparison to the no stimulated platelets (P < 0.001), with 100% correct classification. Computerized fractal analysis of platelet shape by transmission electron microscopy can provide accurate, quantitative, data to study platelet activation. The results may play important roles in the evaluation of the platelets status in pathological conditions, like as atherosclerosis and diabetes mellitus, where in in vivo activated platelets have been described.

  17. NOX Activity Is Increased in Mild Cognitive Impairment

    PubMed Central

    Gupta, Sunita; Parrino, Taryn E.; Knight, Alecia G.; Ebenezer, Philip J.; Weidner, Adam M.; LeVine, Harry; Keller, Jeffrey N.; Markesbery, William R.

    2010-01-01

    Abstract This study was undertaken to investigate the profile of NADPH oxidase (NOX) in the clinical progression of Alzheimer's disease (AD). Specifically, NOX activity and expression of the regulatory subunit p47phox and the catalytic subunit gp91phox was evaluated in affected (superior and middle temporal gyri) and unaffected (cerebellum) brain regions from a longitudinally followed group of patients. This group included both control and late-stage AD subjects, and also subjects with preclinical AD and with amnestic mild cognitive impairment (MCI) to evaluate the profile of NOX in the earliest stages of dementia. Data show significant elevations in NOX activity and expression in the temporal gyri of MCI patients as compared with controls, but not in preclinical or late-stage AD samples, and not in the cerebellum. Immunohistochemical evaluations of NOX expression indicate that whereas microglia express high levels of gp91phox, moderate levels of gp91phox also are expressed in neurons. Finally, in vitro experiments showed that NOX inhibition blunted the ability of oligomeric amyloid beta peptides to injure cultured neurons. Collectively, these data show that NOX expression and activity are upregulated specifically in a vulnerable brain region of MCI patients, and suggest that increases in NOX-associated redox pathways in neurons might participate in the early pathogenesis of AD. Antioxid. Redox Signal. 12, 1371–1382. PMID:19929442

  18. Increased nitrite reductase activity of fetal versus adult ovine hemoglobin

    PubMed Central

    Blood, Arlin B.; Tiso, Mauro; Verma, Shilpa T.; Lo, Jennifer; Joshi, Mahesh S.; Azarov, Ivan; Longo, Lawrence D.; Gladwin, Mark T.; Kim-Shapiro, Daniel B.; Power, Gordon G.

    2009-01-01

    Growing evidence indicates that nitrite, NO2−, serves as a circulating reservoir of nitric oxide (NO) bioactivity that is activated during physiological and pathological hypoxia. One of the intravascular mechanisms for nitrite conversion to NO is a chemical nitrite reductase activity of deoxyhemoglobin. The rate of NO production from this reaction is increased when hemoglobin is in the R conformation. Because the mammalian fetus exists in a low-oxygen environment compared with the adult and is exposed to episodes of severe ischemia during the normal birthing process, and because fetal hemoglobin assumes the R conformation more readily than adult hemoglobin, we hypothesized that nitrite reduction to NO may be enhanced in the fetal circulation. We found that the reaction was faster for fetal than maternal hemoglobin or blood and that the reactions were fastest at 50–80% oxygen saturation, consistent with an R-state catalysis that is predominant for fetal hemoglobin. Nitrite concentrations were similar in blood taken from chronically instrumented normoxic ewes and their fetuses but were elevated in response to chronic hypoxia. The findings suggest an augmented nitrite reductase activity of fetal hemoglobin and that the production of nitrite may participate in the regulation of vascular NO homeostasis in the fetus. PMID:19028797

  19. The Potential for Pocket Parks to Increase Physical Activity

    PubMed Central

    Cohen, Deborah A.; Marsh, Terry; Williamson, Stephanie; Han, Bing; Derose, Kathryn Pitkin; Golinelli, Daniella; McKenzie, Thomas L.

    2014-01-01

    Purpose To assess the use of new pocket parks in low-income neighborhoods. Setting Los Angeles Subjects Parks users and residents living within ½ mile of 3 pocket parks and 15 neighborhood parks Intervention The creation of pocket parks Design Quasi-experimental post-only comparison Measures We used the System of Observing Play and Recreation in Communities (SOPARC) to measure park use and park-based physical activity and surveyed park users and residents about their park use. Analysis We surveyed 392 and 432 household members within one-half mile of the 3 pocket parks before and after park construction, respectively, as well as 71 pocket park users and compared them to 992 neighborhood park users and 342 residents living within ½ mile of other neighborhood parks. We compared pocket park use to playground area use in the larger neighborhood parks. We used descriptive statistics and Generalized Estimating Equations for the analysis. Results Overall, pocket park use compared favorably in promoting moderate-to-vigorous physical activity with that of existing playground space in nearby parks and they were cost-effective at $0.73/MET hour gained. Pocket park visitors walked an average of 0.25 miles to get there. Conclusions Pocket parks, when perceived as attractive and safe destinations, may increase physical activity by encouraging families with children to walk there. Additional strategies and programs may be needed to encourage more residents to use the parks. PMID:24380461

  20. Effect of increasing the choice of active options on children’s physical activity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objectives: To determine whether increasing the choice of physical activity options increases the duration and intensity of children’s physical activity. Design: This cross-sectional laboratory study included gender (male, female) and choice group [single toy (no choice), three toys (low choice...

  1. Use of active video games to increase physical activity in children: a (virtual) reality?

    PubMed

    Foley, Louise; Maddison, Ralph

    2010-02-01

    There has been increased research interest in the use of active video games (in which players physically interact with images onscreen) as a means to promote physical activity in children. The aim of this review was to assess active video games as a means of increasing energy expenditure and physical activity behavior in children. Studies were obtained from computerized searches of multiple electronic bibliographic databases. The last search was conducted in December 2008. Eleven studies focused on the quantification of the energy cost associated with playing active video games, and eight studies focused on the utility of active video games as an intervention to increase physical activity in children. Compared with traditional nonactive video games, active video games elicited greater energy expenditure, which was similar in intensity to mild to moderate intensity physical activity. The intervention studies indicate that active video games may have the potential to increase free-living physical activity and improve body composition in children; however, methodological limitations prevent definitive conclusions. Future research should focus on larger, methodologically sound intervention trials to provide definitive answers as to whether this technology is effective in promoting long-term physical activity in children.

  2. Presynaptic α4β2 nicotinic acetylcholine receptors increase glutamate release and serotonin neuron excitability in the dorsal raphe nucleus.

    PubMed

    Garduño, Julieta; Galindo-Charles, Luis; Jiménez-Rodríguez, Javier; Galarraga, Elvira; Tapia, Dagoberto; Mihailescu, Stefan; Hernandez-Lopez, Salvador

    2012-10-24

    Several behavioral effects of nicotine are mediated by changes in serotonin (5-HT) release in brain areas that receive serotonergic afferents from the dorsal raphe nucleus (DRN). In vitro experiments have demonstrated that nicotine increases the firing activity in the majority of DRN 5-HT neurons and that DRN contains nicotinic acetylcholine receptors (nAChRs) located at both somata and presynaptic elements. One of the most common presynaptic effects of nicotine is to increase glutamate release. Although DRN receives profuse glutamatergic afferents, the effect of nicotine on glutamate release in the DRN has not been studied in detail. Using whole-cell recording techniques, we investigated the effects of nicotine on the glutamatergic input to 5-HT DRN neurons in rat midbrain slices. Low nicotine concentrations, in the presence of bicuculline and tetrodotoxin (TTX), increased the frequency but did not change the amplitude of glutamate-induced EPSCs, recorded from identified 5-HT neurons. Nicotine-induced increase of glutamatergic EPSC frequency persisted 10-20 min after drug withdrawal. This nicotinic effect was mimicked by exogenous administration of acetylcholine (ACh) or inhibition of ACh metabolism. In addition, the nicotine-induced increase in EPSC frequency was abolished by blockade of α4β2 nAChRs, voltage-gated calcium channels, or intracellular calcium signaling but not by α7 nAChR antagonists. These data suggest that both nicotine and endogenous ACh can increase glutamate release through activation of presynaptic α4β2 but not α7 nAChRs in the DRN. The effect involves long-term changes in synaptic function, and it is dependent on voltage-gated calcium channels and presynaptic calcium stores.

  3. Raman Spectroscopy of a-C:H Films Deposited Using Ar + H2 + C7H8 Plasma CVD

    NASA Astrophysics Data System (ADS)

    Dong, Xiao; Koga, Kazunori; Yamashita, Daisuke; Seo, Hyunwoong; Itagaki, Naho; Shiratani, Masaharu; Setsuhara, Yuichi; Sekine, Makoto; Hori, Masaru

    2015-09-01

    We investigated the effects of ion energy on Raman spectra of a-C:H films prepared by Ar + H2 + C7H8 plasma CVD. Raman spectra were measured with a laser Raman spectrometer (JASCO NRS-3100). Both the D-peak position and G-peak position shift toward higher wavenumbers as ion energy increases. The intensity ratio of the D-peak and G-peak, ID/IG increases with increasing the ion energy, indicating that the amount of ring-like sp2 clusters increases. The H content in a-C:H derived from photoluminescence (PL) background decreases with increasing the ion energy. The full width at half maximum of the G-peak, FWHMG related to the C-C sp3 content and H content increases with increasing the ion energy to 100 eV, whereas it decreases with increasing further the ion energy to 105 eV. The variation of FWHMG is consistent with that of mass density. There results indicate that the structure of a-C:H films transforms from polymer-like carbon to diamond-like one with increasing the ion energy above the threshold value of ~ 100 eV.

  4. Highly-substrate active isoenzyme acetylcholinesterase-II, in rosy eye mutant of Aedes aegypti mosquito.

    PubMed

    Mourya, D T; Gokhale, M D; Barde, P V; Deobagkar, D N

    2001-08-01

    Insecticide bioassays were carried out on larvae and adults of rosy eye mutant and wildtype strains of A. aegypti. Both the strains were equally susceptible to DDT, malathion and deltamethrin. Biochemical assays showed an increase in acetylcholinesterase enzyme (AChE) activity in all the stages of mutant strain with both the substrates i.e. acetylthiocholine iodide and S-butyrylthiocholine iodide. However, there was no difference in the percent inhibition of enzyme activity with propoxur in these two strains. Polyacrylamide gel electrophoresis performed in native conditions on the homogenates of adults of rosy eye mosquitoes showed that AChE-II allele was highly active with the substrate acetylthiocholine iodide as compared to wildtype strain. Frequency of the highly active AChE-II allele in the mutant strain was about 68%, whereas it was about 5% in the wildtype strain.

  5. Mini Review: Anticholinergic Activity as a Behavioral Pathology of Lewy Body Disease and Proposal of the Concept of "Anticholinergic Spectrum Disorders".

    PubMed

    Hori, Koji; Konishi, Kimiko; Hosoi, Misa; Tomioka, Hiroi; Tani, Masayuki; Kitajima, Yuka; Hachisu, Mitsugu

    2016-01-01

    Given the relationship between anticholinergic activity (AA) and Alzheimer's disease (AD), we rereview our hypothesis of the endogenous appearance of AA in AD. Briefly, because acetylcholine (ACh) regulates not only cognitive function but also the inflammatory system, when ACh downregulation reaches a critical level, inflammation increases, triggering the appearance of cytokines with AA. Moreover, based on a case report of a patient with mild AD and slightly deteriorated ACh, we also speculate that AA can appear endogenously in Lewy body disease due to the dual action of the downregulation of ACh and hyperactivity of the hypothalamic-pituitary-adrenal axis. Based on these hypotheses, we consider AA to be a behavioral pathology of Lewy body disease. We also propose the concept of "anticholinergic spectrum disorders," which encompass a variety of conditions, including AD, Lewy body disease, and delirium. Finally, we suggest the prescription of cholinesterase inhibitors to patients in this spectrum of disorders to abolish AA by upregulating ACh.

  6. NIMS Observes Increased Activity at Loki Patera, Io

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Loki Patera, historically the most active and persistent hot spot on Io, is located on the hemisphere of Io always facing Jupiter. Loki Patera was the site of two plumes during the Voyager encounters, which were not seen during the early orbits of Galileo. Ground-based observers reported Loki Patera to be unusually dim during this time, marking a period of low volcanic activity.

    On 21 February 1997, during Galileo's sixth orbit, the Near Infrared Mapping Spectrometer (NIMS) on the Galileo spacecraft observed Io in daylight from a range of approximately 703,000 km (440,000 miles). The image on the left shows Io at a wavelength of 2.95 microns. Loki Patera is seen to be relatively quiescent (at longer wavelengths which are more sensitive to thermal emission, Loki Patera is more noticeable).

    A few weeks later, on March 12th 1997, ground based observers using the Infra-Red Telescope Facility (IRTF) on Mauna Kea, Hawaii, observed an intense brightening in the Loki region, so much that Loki was contributing 75% of Io's in-eclipse flux for this hemisphere. A large eruption was taking place! Other ground-based observations through March, April and May tracked the course of the activity and confirmed its location at Loki Patera.

    On 4 April 1997, NIMS again observed Io during the seventh orbit from a range of 556,000 km (348,000 miles), with Loki Patera positioned in darkness, close to the limb. The image on the right shows the increase in activity at Loki Patera, again at 2.95 microns. A preliminary single temperature fit to NIMS orbit seven Loki Patera hot spot data yields a temperature of 500 K and an area of over 800 square kilometers. That the image is so bright at this wavelength is an indication of the areal extent of the activity. It is also probable that some part of the volcanic material being erupted or exposed is at considerably higher temperatures than that of the 500 K single-temperature fit.

    Io is under observation by ground-based observers under

  7. AQW051, a novel, potent and selective α7 nicotinic ACh receptor partial agonist: pharmacological characterization and phase I evaluation

    PubMed Central

    Feuerbach, Dominik; Pezous, Nicole; Weiss, Markus; Shakeri-Nejad, Kasra; Lingenhoehl, Kurt; Hoyer, Daniel; Hurth, Konstanze; Bilbe, Graeme; Pryce, Christopher R; McAllister, Kevin; Chaperon, Frederique; Kucher, Klaus; Johns, Donald; Blaettler, Thomas; Lopez Lopez, Cristina

    2015-01-01

    Background and Purpose Activation of the α7 nicotinic ACh receptor (nACh receptor) is considered an attractive target for the treatment of cognitive impairment associated with neurological disorders. Here we describe the novel α7-nACh receptor agonist AQW051 as a promising drug candidate for this indication. Experimental Approach AQW051 was functionally characterized in vitro and cognitive effects evaluated in rodent behavioural models. Pharmacokinetics and tolerability were evaluated in three phase I placebo-controlled studies in 180 healthy subjects. Key Results In vitro, AQW051 bound with high affinity to α7-nACh receptors and stimulated calcium influx in cells recombinantly expressing the human α7-nACh receptor. In vivo, AQW051 demonstrated good oral bioavailability and rapid penetration into the rodent brain. AQW051 administered over a broad dose range facilitated learning/memory performance in the object recognition and social recognition test in mice and the water maze model in aged rats. Clinically, AQW051 was well tolerated in healthy young and elderly subjects, with an adverse event (AE) profile comparable with placebo. No serious AEs were reported and all AEs were either mild or moderate in severity at single oral doses up to 200 mg and multiple daily doses up to 75 mg. Once-daily oral administration of AQW051 resulted in continuous exposure and a two- to threefold accumulation compared with steady state was achieved by 1 week. Conclusions and Implications These data support further development of AQW051 as a cognitive-enhancing agent, as a therapeutic, for example, in Alzheimer's disease or schizophrenia. PMID:25363835

  8. Increased microglial catalase activity in multiple sclerosis grey matter.

    PubMed

    Gray, Elizabeth; Kemp, Kevin; Hares, Kelly; Redondo, Julianna; Rice, Claire; Scolding, Neil; Wilkins, Alastair

    2014-04-22

    Chronic demyelination, on-going inflammation, axonal loss and grey matter neuronal injury are likely pathological processes that contribute to disease progression in multiple sclerosis (MS). Although the precise contribution of each process and their aetiological substrates is not fully known, recent evidence has implicated oxidative damage as a major cause of tissue injury in MS. The degree of tissue injury caused by oxidative molecules, such as reactive oxygen species (ROS), is balanced by endogenous anti-oxidant enzymes which detoxify ROS. Understanding endogenous mechanisms which protect the brain against oxidative injury in MS is important, since enhancing anti-oxidant responses is a major therapeutic strategy for preventing irreversible tissue injury in the disease. Our aims were to determine expression and activity levels of the hydrogen peroxide-reducing enzyme catalase in MS grey matter (GM). In MS GM, a catalase enzyme activity was elevated compared to control GM. We measured catalase protein expression by immune dot-blotting and catalase mRNA by a real-time polymerase chain reaction (RT-PCR). Protein analysis studies showed a strong positive correlation between catalase and microglial marker IBA-1 in MS GM. In addition, calibration of catalase mRNA level with reference to the microglial-specific transcript AIF-1 revealed an increase in this transcript in MS. This was reflected by the extent of HLA-DR immunolabeling in MS GM which was significantly elevated compared to control GM. Collectively, these observations provide evidence that microglial catalase activity is elevated in MS grey matter and may be an important endogenous anti-oxidant defence mechanism in MS.

  9. Writer's cramp: increased dorsal premotor activity during intended writing.

    PubMed

    Delnooz, Cathérine C S; Helmich, Rick C; Medendorp, W P; Van de Warrenburg, Bart P C; Toni, Ivan

    2013-03-01

    Simple writer's cramp (WC) is a task-specific form of dystonia, characterized by abnormal movements and postures of the hand during writing. It is extremely task-specific, since dystonic symptoms can occur when a patient uses a pencil for writing, but not when it is used for sharpening. Maladaptive plasticity, loss of inhibition, and abnormal sensory processing are important pathophysiological elements of WC. However, it remains unclear how those elements can account for its task-specificity. We used fMRI to isolate cerebral alterations associated with the task-specificity of simple WC. Subjects (13 simple WC patients, 20 matched controls) imagined grasping a pencil to either write with it or sharpen it. On each trial, we manipulated the pencil's position and the number of imagined movements, while monitoring variations in motor output with electromyography. We show that simple WC is characterized by abnormally increased activity in the dorsal premotor cortex (PMd) when imagined actions are specifically related to writing. This cerebral effect was independent from the known deficits in dystonia in generating focal motor output and in processing somatosensory feedback. This abnormal activity of the PMd suggests that the task-specific element of simple WC is primarily due to alterations at the planning level, in the computations that transform a desired action outcome into the motor commands leading to that action. These findings open the way for testing the therapeutic value of interventions that take into account the computational substrate of task-specificity in simple WC, e.g. modulations of PMd activity during the planning phase of writing.

  10. Increased oscillatory theta activation evoked by violent digital game events.

    PubMed

    Salminen, Mikko; Ravaja, Niklas

    2008-04-11

    The authors examined electroencephalographic (EEG) oscillatory responses to two violent events, the player character wounding and killing an opponent character with a gun, in the digital game James Bond 007: NightFire. EEG was recorded from 25 (16 male) right-handed healthy young adults. EEG data were segmented into one 1-s baseline epoch before each event and two 1-s epochs after event onset. Power estimates (microV(2)) were derived with the fast Fourier transform (FFT) for each artefact free event. Both of the studied events evoked increased occipital theta (4-6Hz) responses as compared to the pre-event baseline. The wounding event evoked also increased occipital high theta (6-8Hz) response and the killing event evoked low alpha (8-10Hz) asymmetry over the central electrodes, both relative to the pre-event baseline. The results are discussed in light of facial electromyographic and electrodermal activity responses evoked by these same events, and it is suggested that the reported EEG responses may be attributable to affective processes related to these violent game events.

  11. Microstructure of a-C:H films prepared on a microtrench and analysis of ions and radicals behavior

    SciTech Connect

    Hirata, Yuki; Choi, Junho

    2015-08-28

    Amorphous carbon films (a-C:H) were prepared on a microtrench (4-μm pitch and 4-μm depth), and the uniformity of film thickness and microstructure of the films on the top, sidewall, and bottom surfaces of the microtrench were evaluated by scanning electron microscopy and Raman spectroscopy. The a-C:H films were prepared by bipolar-type plasma based ion implantation and deposition (bipolar PBII&D), and the negative pulse voltage, which is the main parameter dominating the film structure, was changed from −1.0 to −15 kV. Moreover, the behavior of ions and radicals was analyzed simultaneously by combining the calculation methods of Particle-In-Cell/Monte Carlo Collision (PIC-MCC) and Direct Simulation Monte Carlo (DSMC) to investigate the coating mechanism for the microtrench. The results reveal that the thickness uniformity of a-C:H films improves with decreasing negative pulse voltage due to the decreasing inertia of incoming ions from the trench mouth, although the film thickness on the sidewall tends to be much smaller than that on the top and bottom surfaces of the trench. The normalized flux and the film thickness show similar behavior, i.e., the normalized flux or thickness at the bottom surface increases at low negative pulse voltages and then saturates at a certain value, whereas at the sidewall it monotonically decreases with increasing negative voltage. The microstructure of a-C:H films on the sidewall surface is very different from that on the top and bottom surfaces. The film structure at a low negative pulse voltage shifts to more of a polymer-like carbon (PLC) structure due to the lower incident energy of ions. Although the radical flux on the sidewall increases slightly, the overall film structure is not significantly changed because this film formation at a low negative voltage is originally dominated by radicals. On the other hand, the flux of radicals is dominant on the sidewall in the case of high negative pulse voltage, resulting in a

  12. Microstructure of a-C:H films prepared on a microtrench and analysis of ions and radicals behavior

    NASA Astrophysics Data System (ADS)

    Hirata, Yuki; Choi, Junho

    2015-08-01

    Amorphous carbon films (a-C:H) were prepared on a microtrench (4-μm pitch and 4-μm depth), and the uniformity of film thickness and microstructure of the films on the top, sidewall, and bottom surfaces of the microtrench were evaluated by scanning electron microscopy and Raman spectroscopy. The a-C:H films were prepared by bipolar-type plasma based ion implantation and deposition (bipolar PBII&D), and the negative pulse voltage, which is the main parameter dominating the film structure, was changed from -1.0 to -15 kV. Moreover, the behavior of ions and radicals was analyzed simultaneously by combining the calculation methods of Particle-In-Cell/Monte Carlo Collision (PIC-MCC) and Direct Simulation Monte Carlo (DSMC) to investigate the coating mechanism for the microtrench. The results reveal that the thickness uniformity of a-C:H films improves with decreasing negative pulse voltage due to the decreasing inertia of incoming ions from the trench mouth, although the film thickness on the sidewall tends to be much smaller than that on the top and bottom surfaces of the trench. The normalized flux and the film thickness show similar behavior, i.e., the normalized flux or thickness at the bottom surface increases at low negative pulse voltages and then saturates at a certain value, whereas at the sidewall it monotonically decreases with increasing negative voltage. The microstructure of a-C:H films on the sidewall surface is very different from that on the top and bottom surfaces. The film structure at a low negative pulse voltage shifts to more of a polymer-like carbon (PLC) structure due to the lower incident energy of ions. Although the radical flux on the sidewall increases slightly, the overall film structure is not significantly changed because this film formation at a low negative voltage is originally dominated by radicals. On the other hand, the flux of radicals is dominant on the sidewall in the case of high negative pulse voltage, resulting in a deviation

  13. nAChR dysfunction as a common substrate for schizophrenia and comorbid nicotine addiction: current trends and perspectives

    PubMed Central

    Parikh, Vinay; Kutlu, Munir Gunes; Gould, Thomas J.

    2016-01-01

    Introduction The prevalence of tobacco use in the population with schizophrenia is enormously high. Moreover, nicotine dependence is found to be associated with symptom severity and poor outcome in patients with schizophrenia. The neurobiological mechanisms that explain schizophrenia-nicotine dependence comorbidity are not known. This study systematically reviews the evidence highlighting the contribution of nicotinic acetylcholine receptors (nAChRs) to nicotine abuse in schizophrenia. Methods Electronic data bases (Medline, Google Scholar, and Web of Science) were searched using the selected key words that match the aims set forth for this review. A total of 275 articles were used for the qualitative synthesis of this review. Results Substantial evidence from preclinical and clinical studies indicated that dysregulation of α7 and β2-subunit containing nAChRs account for the cognitive and affective symptoms of schizophrenia and nicotine use may represent a strategy to remediate these symptoms. Additionally, recent meta-analyses proposed that early tobacco use may itself increase the risk of developing schizophrenia. Genetic studies demonstrating that nAChR dysfunction that may act as a shared vulnerability factor for comorbid tobacco dependence and schizophrenia were found to support this view. The development of nAChR modulators was considered an effective therapeutic strategy to ameliorate psychiatric symptoms and to promote smoking cessation in schizophrenia patients. Conclusions The relationship between schizophrenia and smoking is complex. While the debate for the self-medication versus addiction vulnerability hypothesis continues, it is widely accepted that a dysfunction in the central nAChRs represent a common substrate for various symptoms of schizophrenia and comorbid nicotine dependence. PMID:26803692

  14. Highly Sensitive and Selective Immuno-capture/Electrochemical Assay of Acetylcholinesterase Activity in Red Blood Cells: A Biomarker of Exposure to Organophosphorus Pesticides and Nerve Agents

    SciTech Connect

    Chen, Aiqiong; Du, Dan; Lin, Yuehe

    2012-02-09

    Acetylcholinesterase (AChE) enzyme activity in red blood cells (RBCs) is a useful biomarker for biomonitoring of exposures to organophosphorus (OP) pesticides and chemical nerve agents. In this paper, we reported a new method for AChE activity assay based on selective immuno-capture of AChE from biological samples followed by enzyme activity assay of captured AChE using a disposable electrochemical sensor. The electrochemical sensor is based on multiwalled carbon nanotubes-gold nanocomposites (MWCNTs-Au) modified screen printed carbon electrode (SPCE). Upon the completion of immunoreaction, the target AChE (including active and inhibited) is captured onto the electrode surface and followed by an electrochemical detection of enzymatic activity in the presence of acetylthiocholine. A linear response is obtained over standard AChE concentration range from 0.1 to 10 nM. To demonstrate the capability of this new biomonitoring method, AChE solutions dosed with different concentration of paraoxon were used to validate the new AChE assay method. AChE inhibition in OP dosed solutions was proportional to its concentration from 0.2 to 50 nM. The new AChE activity assay method for biomonitoring of OP exposure was further validated with in-vitro paraoxon-dosed RBC samples. The established electrochemical sensing platform for AChE activity assay not only avoids the problem of overlapping substrate specificity with esterases by using selective antibody, but also eliminates potential interference from other electroactive species in biological samples. It offers a new approach for sensitive, selective, and rapid AChE activity assay for biomonitoring of exposures to OPs.

  15. Acetylcholine from the mesopontine tegmental nuclei differentially affects methamphetamine induced locomotor activity and neurotransmitter levels in the mesolimbic pathway

    PubMed Central

    Dobbs, Lauren K.; Mark, Gregory P.

    2012-01-01

    Methamphetamine (MA) increases dopamine (DA) levels within the mesolimbic pathway and acetylcholine (ACh), a neurotransmitter known to increase DA cell firing and release and mediate reinforcement, within the ventral tegmental area (VTA). The laterodorsal tegmental (LDT) and pedunculopontine tegmental (PPT) nuclei provide cholinergic input to the VTA; however, the contribution of LDT- and PPT-derived ACh to MA-induced DA and ACh levels and locomotor activation remains unknown. The first experiment examined the role of LDT-derived ACh in MA locomotor activation by reversibly inhibiting these neurons with bilateral intra-LDT microinjections of the M2 receptor agonist oxotremorine (OXO). Male C57BL/6 J mice were given a bilateral 0.1 µl OXO (0, 1, or 10 nM/side) microinjection immediately prior to IP saline or MA (2 mg/kg). The highest OXO concentration significantly inhibited both saline-and MA-primed locomotor activity. In a second set of experiments we characterized the individual contributions of ACh originating in the LDT or pedunculopontine tegmental nucleus (PPT) to MA-induced levels of ACh and DA by administering intra-LDT or PPT OXO and performing in vivo microdialysis in the VTA and NAc. Intra-LDT OXO dose-dependently attenuated the MA-induced increase in ACh within the VTA but had no effect on DA in NAc. Intra-PPT OXO had no effect on ACh or DA levels within the VTA or NAc, respectively. We conclude that LDT, but not PPT, ACh is important in locomotor behavior and the cholinergic, but not dopaminergic, response to systemic MA. PMID:21945297

  16. Acid-activated biochar increased sulfamethazine retention in soils.

    PubMed

    Vithanage, Meththika; Rajapaksha, Anushka Upamali; Zhang, Ming; Thiele-Bruhn, Sören; Lee, Sang Soo; Ok, Yong Sik

    2015-02-01

    Sulfamethazine (SMZ) is an ionizable and highly mobile antibiotic which is frequently found in soil and water environments. We investigated the sorption of SMZ onto soils amended with biochars (BCs) at varying pH and contact time. Invasive plants were pyrolyzed at 700 °C and were further activated with 30 % sulfuric (SBBC) and oxalic (OBBC) acids. The sorption rate of SMZ onto SBBC and OBBC was pronouncedly pH dependent and was decreased significantly when the values of soil pH increased from 3 to 5. Modeled effective sorption coefficients (K D,eff) values indicated excellent sorption on SBBC-treated loamy sand and sandy loam soils for 229 and 183 L/kg, respectively. On the other hand, the low sorption values were determined for OBBC- and BBC700-treated loamy sand and sandy loam soils. Kinetic modeling demonstrated that the pseudo second order model was the best followed by intra-particle diffusion and the Elovich model, indicating that multiple processes govern SMZ sorption. These findings were also supported by sorption edge experiments based on BC characteristics. Chemisorption onto protonated and ligand containing functional groups of the BC surface, and diffusion in macro-, meso-, and micro-pores of the acid-activated BCs are the proposed mechanisms of SMZ retention in soils. Calculated and experimental q e (amount adsorbed per kg of the adsorbent at equilibrium) values were well fitted to the pseudo second order model, and the predicted maximum equilibrium concentration of SBBC for loamy sand soils was 182 mg/kg. Overall, SBBC represents a suitable soil amendment because of its high sorption rate of SMZ in soils.

  17. Deconstruction of the α4β2 Nicotinic Acetylchloine (nACh) Receptor Positive Allosteric Modulator des-Formylflustrabromine (dFBr)

    PubMed Central

    German, Nadezhda; Kim, Jin-Sung; Jain, Atul; Dukat, Malgorzata; Pandya, Anshul; Ma, Yilong; Weltzin, Maegan; Schulte, Marvin K.; Glennon, Richard A.

    2011-01-01

    des -Formylflustrabromine (dFBr; 1), perhaps the first selective positive allosteric modulator of α4β2 neuronal nicotinic acetylcholine (nACh) receptors, was deconstructed to determine which structural features contribute to its actions on receptors expressed in Xenopus ooycytes using 2-electrode voltage clamp techniques. Although the intact structure of 1 was found optimal, several deconstructed analogs retained activity. Neither the 6-bromo substituent nor the entire 2-position chain is required for activity. In particular, reduction of the olefinic side chain of 1, as seen with 6, not only resulted in retention of activity/potency but in enhanced selectivity for α4β2 versus α7 nACh receptors. Pharmacophoric features for the allosteric modulation of α4β2 nACh receptors by 1 were identified. PMID:21905680

  18. Immobilization induces a very rapid increase in osteoclast activity

    NASA Astrophysics Data System (ADS)

    Heer, Martina; Baecker, Natalie; Mika, Claudia; Boese, Andrea; Gerzer, Rupert

    2005-07-01

    We studied in a randomized, strictly controlled cross-over design, the effects of 6 days 6° head-down tilt bed rest (HDT) in eight male healthy subjects in our metabolic ward. The study consisted of two periods (phases) of 11 days each in order to allow for the test subjects being their own controls. Both study phases were identical with respect to environmental conditions, study protocol and diet. Two days before arriving in the metabolic ward the subjects started with a diet. The diet was continued in the metabolic ward. The metabolic ward period (1l days) was divided into three parts: 4 ambulatory days, 6 days either HDT or control and 1 recovery day. Continuous urine collection started on the first day in the metabolic ward to analyze calcium excretion and bone resorption markers. On the 2nd ambulatory day in the metabolic ward and on the 5th day in HDT or control blood was drawn to analyze serum calcium, parathyroid hormone, and bone formation markers. Urinary calcium excretion was, as early as the first day in immobilization, increased (p<0.01). CTX- and NTX-excretion stayed unchanged in the first 24 h in HDT compared to the control. But already on the 2nd day of immobilization, both bone resorption markers significantly increased. We conclude from these results—pronounced rise of bone resorption markers—that already 24 h of immobilization induce a significant rise in osteoclast activity in healthy subjects. Thus, it appears possible to use short-term bed rest studies as a first step for the development of countermeasures to immobilization.

  19. Increased 5. cap alpha. -reductase activity in idiopathic hirsutism

    SciTech Connect

    Serafini, P.; Lobo, R.A.

    1985-01-01

    In vitro, genital skin 5..cap alpha..-reductase activity (5..cap alpha..-RA) was measured in ten hirsute women with normal androgen levels (idiopathic hirsutism (IH)) and in ten hirsute women with elevated androgen levels (polycystic ovary syndrome (PCO)) in order to determine the influence of secreted androgens on 5..cap alpha..-RA. In vitro 5..cap alpha..-RA was assessed by incubations of skin with /sup 14/C-testosterone (T) for 2 hours, after which steroids were separated and the radioactivity of dihydrotestosterone (DHT) and 5..cap alpha..-androstane 3..cap alpha..-17..beta..-estradiol (3..cap alpha..-diol) in specific eluates were determined. All androgens were normal in IH with the exception of higher levels of 3..cap alpha..-diol glucuronide which were similar to the levels of PCO. The conversion ratio (CR) of T to DHT in IH and PCO were similar, yet significantly greater than the CR of control subjects. The CR of T to 3..cap alpha..-diol in IH and PCO were similar, yet higher than in control subjects. Serum androgens showed no correlation with 5..cap alpha..-RA, while the CR of T to DHT showed a significant positive correlation with the Ferriman and Gallwey score. The increased 5..cap alpha..-RA in IH appears to be independent of serum androgen levels and is, therefore, an inherent abnormality. The term idiopathic is a misnomer, because hirsutism in these patients may be explained on the basis of increased skin 5..cap alpha..-RA.

  20. Altered behavior in spotted hyenas associated with increased human activity

    USGS Publications Warehouse

    Boydston, Erin E.; Kapheim, Karen M.; Watts, Heather E.; Szykman, Micaela; Holekamp, Kay E.

    2003-01-01

    To investigate how anthropogenic activity might affect large carnivores, we studied the behaviour of spotted hyenas (Crocuta crocuta) during two time periods. From 1996 to 1998, we documented the ecological correlates of space utilization patterns exhibited by adult female hyenas defending a territory at the edge of a wildlife reserve in Kenya. Hyenas preferred areas near dense vegetation but appeared to avoid areas containing the greatest abundance of prey, perhaps because these were also the areas of most intensive livestock grazing. We then compared hyena behaviour observed in 1996–98 with that observed several years earlier and found many differences. Female hyenas in 1996–98 were found farther from dens, but closer to dense vegetation and to the edges of their territory, than in 1988–90. Recent females also had larger home ranges, travelled farther between consecutive sightings, and were more nocturnal than in 1988–90. Finally, hyenas occurred in smaller groups in 1996–98 than in 1988–90. We also found several changes in hyena demography between periods. We next attempted to explain differences observed between time periods by testing predictions of hypotheses invoking prey abundance, climate, interactions with lions, tourism and livestock grazing. Our data were consistent with the hypothesis that increased reliance on the reserve for livestock grazing was responsible for observed changes. That behavioural changes were not associated with decreased hyena population density suggests the behavioural plasticity typical of this species may protect it from extinction.

  1. Platelet-activating factor-induced increases in glucose kinetics

    SciTech Connect

    Lang, C.H.; Dobrescu, C.; Hargrove, D.M.; Bagby, G.J.; Spitzer, J.J. )

    1988-02-01

    Platelet-activating factor (PAF) is a postulated mediator of many of the early hemodynamic effects of endotoxin. The aim of the present study was to determine whether in vivo administration of PAF could produce alterations in whole-body glucose metabolism that would mimic those seen during endotoxemia. Glucose kinetics were assessed in chronically catheterized conscious rats by the constant infusion of (6-{sup 3}H)- and (U-{sup 14}C)glucose before and for 4 h after either a bolus injection or a constant infusion of PAF. The bolus injection of PAF elevated the rate of glucose appearance (R{sub a}; 44%) for 1.5 h. The lower PAF infusion rate decreased blood pressure 11% to 104 mmHg, whereas the higher infusion rate decreased pressure 34% to 77 mmHg. Both PAF infusion rates produced elevations in plasma glucose and glucose R{sub a} throughout the 4-h infusion period in a dose-related manner. The PAF infusions also induced dose-related increases in plasma glucagon and catecholamine levels throughout the infusion period. Because the constant infusion of PAF did stimulate many of the hemodynamic and metabolic alterations produced by endotoxin, this study provides additional support for the potential importance of PAF as a mediator of the early hemodynamic and metabolic sequela of endotoxin shock. Furthermore, the PAF-induced changes in glucose metabolism appear to be mediated by the resultant elevation in plasma catecholamines.

  2. Increasing SK2 channel activity impairs associative learning

    PubMed Central

    McKay, Bridget M.; Oh, M. Matthew; Galvez, Roberto; Burgdorf, Jeffrey; Kroes, Roger A.; Weiss, Craig; Adelman, John P.; Moskal, Joseph R.

    2012-01-01

    Enhanced intrinsic neuronal excitability of hippocampal pyramidal neurons via reductions in the postburst afterhyperpolarization (AHP) has been hypothesized to be a biomarker of successful learning. This is supported by considerable evidence that pharmacologic enhancement of neuronal excitability facilitates learning. However, it has yet to be demonstrated that pharmacologic reduction of neuronal excitability restricted to the hippocampus can retard acquisition of a hippocampus-dependent task. Thus, the present study was designed to address this latter point using a small conductance potassium (SK) channel activator NS309 focally applied to the dorsal hippocampus. SK channels are important contributors to intrinsic excitability, as measured by the medium postburst AHP. NS309 increased the medium AHP and reduced excitatory postsynaptic potential width of CA1 neurons in vitro. In vivo, NS309 reduced the spontaneous firing rate of CA1 pyramidal neurons and impaired trace eyeblink conditioning in rats. Conversely, trace eyeblink conditioning reduced levels of SK2 channel mRNA and protein in the hippocampus. Therefore, the present findings indicate that modulation of SK channels is an important cellular mechanism for associative learning and further support postburst AHP reductions in hippocampal pyramidal neurons as a biomarker of successful learning. PMID:22552186

  3. INCREASED SUSCEPTIBILITY OF THE SPONTANEOUSLY HYPERTENSIVE RAT TO CHLORPYRIFOS, AN ORGANOPHOSPHATE PESTICIDE.

    EPA Science Inventory

    Hypertension and hypothermia are common symptoms in rats exposed to chlorpyrifos (CHP), an organophosphate (OP)-based pesticide. CHP inhibits acetylcholinesterase (AChE) activity resulting in central and peripheral stimulation of cholinergic pathways involved in blood pressure ...

  4. In vivo and in vitro effects of fructose on rat brain acetylcholinesterase activity: an ontogenetic study.

    PubMed

    Guimarães, Carine A; Biella, Mairis S; Lopes, Abigail; Deroza, Pedro F; Oliveira, Mariana B; Macan, Tamires P; Streck, Emilio L; Ferreira, Gustavo C; Zugno, Alexandra I; Schuck, Patrícia F

    2014-12-01

    Increased fructose concentrations are the biochemical hallmark of fructosemia, a group of inherited disorders on the metabolic pathway of this sugar. The main clinical findings observed in patients affected by fructosemia include neurological abnormalities with developmental delay, whose pathophysiology is still undefined. In the present work we investigated the in vitro and in vivo effects of fructose on acetylcholinesterase (AchE) activity in brain structures of developing rats. For the in vitro experiments, fructose was added at increasing concentrations to the incubation medium. It was observed that fructose provoked an inhibition of acetylcholinesterase activity in cerebral cortex of 30-day-old-rats, even at low concentrations (0.1 mM). For the in vivo experiments, rats were killed 1 h after a single fructose administration (5 µmol/g). Control group received the same volume of saline solution. We found that AchE activity was increased in cerebral cortex of 30- and 60-day-old rats receiving fructose administration. Finally, we observed that AchE activity was unaffected by acute fructose administration in cerebral cortex, striatum or hippocampus of 15- and 90-day-old rats. The present data suggest that a disruption in cholinergic homeostasis may be involved in the pathophysiology of brain damage observed in young patients affected by fructosemia.

  5. Oxidative stress and damage to erythrocytes in patients with chronic obstructive pulmonary disease--changes in ATPase and acetylcholinesterase activity.

    PubMed

    Bukowska, Bożena; Sicińska, Paulina; Pająk, Aneta; Koceva-Chyla, Aneta; Pietras, Tadeusz; Pszczółkowska, Anna; Górski, Paweł; Koter-Michalak, Maria

    2015-12-01

    The study indicates, for the first time, the changes in both ATPase and AChE activities in the membrane of red blood cells of patients diagnosed with COPD. Chronic obstructive pulmonary disease (COPD) is one of the most common and severe lung disorders. We examined the impact of COPD on redox balance and properties of the membrane of red blood cells. The study involved 30 patients with COPD and 18 healthy subjects. An increase in lipid peroxidation products and a decrease in the content of -SH groups in the membrane of red blood cells in patients with COPD were observed. Moreover, an increase in the activity of glutathione peroxidase and a decrease in superoxide dismutase, but not in catalase activity, were found as well. Significant changes in activities of erythrocyte membrane enzymes in COPD patients were also evident demonstrated by a considerably lowered ATPase activity and elevated AChE activity. Changes in the structure and function of red blood cells observed in COPD patients, together with changes in the activity of the key membrane enzymes (ATPases and AChE), can result from the imbalance of redox status of these cells due to extensive oxidative stress induced by COPD disease.

  6. Relation between dynamics, activity and thermal stability within the cholinesterase family.

    PubMed

    Trovaslet, Marie; Trapp, Marcus; Weik, Martin; Nachon, Florian; Masson, Patrick; Tehei, Moeava; Peters, Judith

    2013-03-25

    Incoherent neutron scattering is one of the most powerful tools for studying dynamics in biological matter. Using the cold neutron backscattering spectrometer IN16 at the Institut Laue Langevin (ILL, Grenoble, France), temperature dependence of cholinesterases' dynamics (human butyrylcholinesterase from plasma: hBChE; recombinant human acetylcholinesterase: hAChE and recombinant mouse acetylcholinesterase: mAChE) was examined using elastic incoherent neutron scattering (EINS). The dynamics was characterized by the averaged atomic mean square displacement (MSD), associated with the sample flexibility at a given temperature. We found MSD values of hAChE above the dynamical transition temperature (around 200K) larger than for mAChE and hBChE, implying that hAChE is more flexible than the other ChEs. Activation energies for thermodynamical transition were extracted through the frequency window model (FWM) (Becker et al. 2004) [1] and turned out to increase from hBChE to mAChE and finally to hAChE, inversely to the MSDs relations. Between 280 and 316K, catalytic studies of these enzymes were carried out using thiocholine esters: at the same temperature, the hAChE activity was systematically higher than the mAChE or hBChE ones. Our results thus suggest a strong correlation between dynamics and activity within the ChE family. We also studied and compared the ChEs thermal inactivation kinetics. Here, no direct correlation with the dynamics was observed, thus suggesting that relations between enzyme dynamics and catalytic stability are more complex. Finally, the possible relation between flexibility and protein ability to grow in crystals is discussed.

  7. Nest predation increases with parental activity: Separating nest site and parental activity effects

    USGS Publications Warehouse

    Martin, T.E.; Scott, J.; Menge, C.

    2000-01-01

    Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators have found similar results. We tested whether nest site effects might yield higher predation during incubation because the most obvious sites are depredated most rapidly. We conducted experiments using nest sites from the previous year to remove parental activity. Our results showed that nest sites have highly repeatable effects on nest predation risk; poor nest sites incurred rapid predation and caused predation rates to be greater during the incubation than nestling stage. This pattern also was exhibited in a bird species with similar (i.e. controlled) parental activity between nesting stages. Once nest site effects are taken into account, nest predation shows a strong proximate increase with parental activity during the nestling stage within and across species. Parental activity and nest sites exert antagonistic influences on current estimates of nest predation between nesting stages and both must be considered in order to understand current patterns of nest predation, which is an important source of natural selection.

  8. Nest predation increases with parental activity: separating nest site and parental activity effects.

    PubMed Central

    Martin, T E; Scott, J; Menge, C

    2000-01-01

    Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators have found similar results. We tested whether nest site effects might yield higher predation during incubation because the most obvious sites are depredated most rapidly. We conducted experiments using nest sites from the previous year to remove parental activity. Our results showed that nest sites have highly repeatable effects on nest predation risk; poor nest sites incurred rapid predation and caused predation rates to be greater during the incubation than nestling stage. This pattern also was exhibited in a bird species with similar (i.e. controlled) parental activity between nesting stages. Once nest site effects are taken into account, nest predation shows a strong proximate increase with parental activity during the nestling stage within and across species. Parental activity and nest sites exert antagonistic influences on current estimates of nest predation between nesting stages and both must be considered in order to understand current patterns of nest predation, which is an important source of natural selection. PMID:11413645

  9. Nicotinic α4 Receptor-Mediated Cholinergic Influences on Food Intake and Activity Patterns in Hypothalamic Circuits.

    PubMed

    García, Ana P; Aitta-aho, Teemu; Schaaf, Laura; Heeley, Nicholas; Heuschmid, Lena; Bai, Yunjing; Barrantes, Francisco J; Apergis-Schoute, John

    2015-01-01

    Nicotinic acetylcholine receptors (nAChRs) play an important role in regulating appetite and have been shown to do so by influencing neural activity in the hypothalamus. To shed light on the hypothalamic circuits governing acetylcholine's (ACh) regulation of appetite this study investigated the influence of hypothalamic nAChRs expressing the α4 subunit. We found that antagonizing the α4β2 nAChR locally in the lateral hypothalamus with di-hydro-ß-erythroidine (DHβE), an α4 nAChR antagonist with moderate affinity, caused an increase in food intake following free access to food after a 12 hour fast, compared to saline-infused animals. Immunocytochemical analysis revealed that orexin/hypocretin (HO), oxytocin, and tyrosine hydroxylase (TH)-containing neurons in the A13 and A12 of the hypothalamus expressed the nAChR α4 subunit in varying amounts (34%, 42%, 50%, and 51%, respectively) whereas melanin concentrating hormone (MCH) neurons did not, suggesting that DHβE-mediated increases in food intake may be due to a direct activation of specific hypothalamic circuits. Systemic DHβE (2 mg/kg) administration similarly increased food intake following a 12 hour fast. In these animals a subpopulation of orexin/hypocretin neurons showed elevated activity compared to control animals and MCH neuronal activity was overall lower as measured by expression of the immediate early gene marker for neuronal activity cFos. However, oxytocin neurons in the paraventricular hypothalamus and TH-containing neurons in the A13 and A12 did not show differential activity patterns. These results indicate that various neurochemically distinct hypothalamic populations are under the influence of α4β2 nAChRs and that cholinergic inputs to the lateral hypothalamus can affect satiety signals through activation of local α4β2 nAChR-mediated transmission.

  10. Muscarinic activation of mitogen-activated protein kinase in PC12 cells.

    PubMed

    Berkeley, J L; Levey, A I

    2000-08-01

    Muscarinic acetylcholine receptors (mAChRs) activate many downstream signaling pathways, some of which can lead to mitogen-activated protein kinase (MAPK) phosphorylation and activation. MAPKs play roles in regulating cell growth, differentiation, and synaptic plasticity. Here, the activation of MAPK was examined in PC12 cells endogenously expressing mAChRs. Western blot analysis using a phosphospecific MAPK antibody revealed a dose-dependent and atropine-sensitive increase in MAPK phosphorylation in cells stimulated with carbachol (CCh). The maximal response occurred after 5 min and was rapidly reduced to baseline. To investigate the receptors responsible for CCh activation of MAPK in PC12 cells, the mAChR subtypes present were determined using RT-PCR and immunoprecipitation. RT-PCR was used to amplify fragments of the appropriate sizes for m1, m4, and m5, and the identities of the bands were confirmed with restriction digests. Immunoprecipitation using subtype-specific antibodies showed that approximately 95% of the expressed receptors were m4, whereas the remaining approximately 5% were m1 and m5. A highly specific m1 toxin completely blocked MAPK phosphorylation in response to CCh stimulation. The mAChR-induced MAPK activation was abolished by protein kinase C down-regulation and partially inhibited by pertussis toxin. Although m1 represents a small proportion of the total mAChR population, pharmacological evidence suggests that m1 is responsible for MAPK activation in PC12 cells.

  11. Methadone's effect on nAChRs--a link between methadone use and smoking?

    PubMed

    Talka, Reeta; Tuominen, Raimo K; Salminen, Outi

    2015-10-15

    Methadone is a long-acting opioid agonist that is frequently prescribed as a treatment for opioid addiction. Almost all methadone maintenance patients are smokers, and there is a correlation between smoking habit and use of methadone. Methadone administration increases tobacco smoking, and heavy smokers use higher doses of methadone. Nevertheless, methadone maintenance patients are willing to quit smoking although their quit rates are low. Studies on nicotine-methadone interactions provide an example of the bedside-to-bench approach, i.e., observations in clinical settings have been studied experimentally in vivo and in vitro. In vivo studies have revealed the interplay between nicotine and the endogenous opioid system. At the receptor level, methadone has been shown to be an agonist of human α7 nAChRs and a non-competitive antagonist of human α4β2 and α3* nAChRs. These drugs do not have significant interactions at the level of drug metabolism, and thus the interaction is most likely pharmacodynamic. The net effect of the interaction may depend on individual characteristics because pharmacogenetic factors influence the disposition of both methadone and nicotine.

  12. Activation of protease activated receptor 1 increases the excitability of the dentate granule neurons of hippocampus

    PubMed Central

    2011-01-01

    Protease activated receptor-1 (PAR1) is expressed in multiple cell types in the CNS, with the most prominent expression in glial cells. PAR1 activation enhances excitatory synaptic transmission secondary to the release of glutamate from astrocytes following activation of astrocytically-expressed PAR1. In addition, PAR1 activation exacerbates neuronal damage in multiple in vivo models of brain injury in a manner that is dependent on NMDA receptors. In the hippocampal formation, PAR1 mRNA appears to be expressed by a subset of neurons, including granule cells in the dentate gyrus. In this study we investigate the role of PAR activation in controlling neuronal excitability of dentate granule cells. We confirm that PAR1 protein is expressed in neurons of the dentate cell body layer as well as in astrocytes throughout the dentate. Activation of PAR1 receptors by the selective peptide agonist TFLLR increased the intracellular Ca2+ concentration in a subset of acutely dissociated dentate neurons as well as non-neuronal cells. Bath application of TFLLR in acute hippocampal slices depolarized the dentate gyrus, including the hilar region in wild type but not in the PAR1-/- mice. PAR1 activation increased the frequency of action potential generation in a subset of dentate granule neurons; cells in which PAR1 activation triggered action potentials showed a significant depolarization. The activation of PAR1 by thrombin increased the amplitude of NMDA receptor-mediated component of EPSPs. These data suggest that activation of PAR1 during normal function or pathological conditions, such as during ischemia or hemorrhage, can increase the excitability of dentate granule cells. PMID:21827709

  13. Kinetic analysis of interactions of different sarin and tabun analogues with human acetylcholinesterase and oximes: is there a structure-activity relationship?

    PubMed

    Aurbek, Nadine; Herkert, Nadja M; Koller, Marianne; Thiermann, Horst; Worek, Franz

    2010-09-06

    The repeated misuse of highly toxic organophosphorus compound (OP) based chemical warfare agents in military conflicts and terrorist attacks poses a continuous threat to the military and civilian sector. The toxic symptomatology of OP poisoning is mainly caused by inhibition of acetylcholinesterase (AChE, E.C. 3.1.1.7) resulting in generalized cholinergic crisis due to accumulation of the neurotransmitter acetylcholine (ACh) in synaptic clefts. Beside atropine as competitive antagonist of ACh at muscarinic ACh receptors oximes as reactivators of OP-inhibited AChE are a mainstay of standard antidotal treatment. However, human AChE inhibited by certain OP is rather resistant to oxime-induced reactivation. The development of more effective oxime-based reactivators may fill the gaps. To get more insight into a potential structure-activity relationship between human AChE, OPs and oximes in vitro studies were conducted to investigate interactions of different tabun and sarin analogues with human AChE and the oximes obidoxime and HI 6 by determination of various kinetic constants. Rate constants for the inhibition of human AChE by OPs, spontaneous dealkylation and reactivation as well as reactivation by obidoxime and HI 6 of OP-inhibited human AChE were determined. The recorded kinetic data did not allow a general statement concerning a structure-activity relationship between human AChE, OP and oximes.

  14. Engaging parents to increase youth physical activity: A systematic review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Parents are often involved in interventions to engage youth in physical activity, but it is not clear which methods for involving parents are effective. A systematic review was conducted of interventions with physical activity and parental components among healthy youth to identify how best to invol...

  15. Elevated temperatures increase the toxicity of pesticide mixtures to juvenile coho salmon.

    PubMed

    Laetz, Cathy A; Baldwin, David H; Hebert, Vincent R; Stark, John D; Scholz, Nathaniel L

    2014-01-01

    Pesticide mixtures and elevated temperatures are parallel freshwater habitat stressors for Pacific salmon in the western United States. Certain combinations of organophosphate (OP) insecticides are known to synergistically increase neurotoxicity in juvenile salmon. The chemicals interact to potentiate the inhibition of brain acetylcholinesterase (AChE) and disrupt swimming behavior. The metabolic activation and detoxification of OPs involve temperature-sensitive enzymatic processes. Salmon are ectothermic, and thus the degree of synergism may vary with ambient temperature in streams, rivers, and lakes. Here we assess the influence of water temperature (12-21°C) on the toxicity of ethoprop and malathion, alone and in combination, to juvenile coho salmon (Oncorhynchus kisutch). A mixture of ethoprop (0.9 μg/L) and malathion (0.75 μg/L) produced synergistic AChE inhibition at 12°C, and the degree of neurotoxicity approximately doubled with a modest temperature increase to 18°C. Slightly lower concentrations of ethoprop (0.5 μg/L) combined with malathion (0.4 μg/L) did not inhibit brain AChE activity but did produce a temperature-dependent reduction in liver carboxylesterase (CaE). The activity of CaE was very sensitive to the inhibitory effects of ethoprop alone and both ethoprop-malathion combinations across all temperatures. Our findings are an example of how non-chemical habitat attributes can increase the relative toxicity of OP mixtures. Surface temperatures currently exceed water quality criteria in many western river segments, and summer thermal extremes are expected to become more frequent in a changing climate. These trends reinforce the importance of pollution reduction strategies to enhance ongoing salmon conservation and recovery efforts.

  16. Opportunities for Public Health to Increase Physical Activity Among Youths

    PubMed Central

    Dorn, Joan M.; Fulton, Janet E.; Janz, Kathleen F.; Lee, Sarah M.; McKinnon, Robin A.; Pate, Russell R.; Pfeiffer, Karin A.; Young, Deborah Rohm; Troiano, Richard P.; Lavizzo-Mourey, Risa

    2015-01-01

    Despite the well-known benefits of youths engaging in 60 or more minutes of daily physical activity, physical inactivity remains a significant public health concern. The 2008 Physical Activity Guidelines for Americans (PAG) provides recommendations on the amount of physical activity needed for overall health; the PAG Midcourse Report (2013) describes effective strategies to help youths meet these recommendations. Public health professionals can be dynamic change agents where youths live, learn, and play by changing environments and policies to empower youths to develop regular physical activity habits to maintain throughout life. We have summarized key findings from the PAG Midcourse Report and outlined actions that public health professionals can take to ensure that all youths regularly engage in health-enhancing physical activity. PMID:25602864

  17. Haemocompatibility of hydrogenated amorphous carbon (a-C:H) films synthesized by plasma immersion ion implantation-deposition

    NASA Astrophysics Data System (ADS)

    Yang, P.; Kwok, S. C. H.; Chu, P. K.; Leng, Y. X.; Chen, J. Y.; Wang, J.; Huang, N.

    2003-05-01

    Diamond-like-carbon has attracted much attention recently as a potential biomaterial in blood contacting biomedical devices. However, previous reports in this area have not adequately addressed the biocompatibility and acceptability of the materials in blood contacting applications. In this study, hydrogenated amorphous carbon (a-C:H) films were fabricated on silicon wafers (1 0 0) using plasma immersion ion implantation-deposition. A series of a-C:H films with different structures and chemical bonds were fabricated under different substrate voltages. The results indicate that film graphitization is promoted at higher substrate bias. The film deposited at a lower substrate bias of -75 V possesses better blood compatibility than the films at higher bias and stainless steel. Our results suggest two possible paths to improve the blood compatibility, suppression of the endogenic clotting system and reduction of platelet activation.

  18. Study of the Peripheral Nerve Fibers Myelin Structure Changes during Activation of Schwann Cell Acetylcholine Receptors

    PubMed Central

    Verdiyan, Ekaterina E.; Allakhverdiev, Elvin S.; Maksimov, Georgy V.

    2016-01-01

    In the present paper we consider a new type of mechanism by which neurotransmitter acetylcholine (ACh) regulates the properties of peripheral nerve fibers myelin. Our data show the importance of the relationship between the changes in the number of Schwann cell (SC) acetylcholine receptors (AChRs) and the axon excitation (different intervals between action potentials (APs)). Using Raman spectroscopy, an effect of activation of SC AChRs on the myelin membrane fluidity was investigated. It was found, that ACh stimulates an increase in lipid ordering degree of the myelin lipids, thus providing evidence for specific role of the “axon-SC” interactions at the axon excitation. It was proposed, that during the axon excitation, the SC membrane K+- depolarization and the Ca2+—influx led to phospholipase activation or exocytosis of intracellular membrane vesicles and myelin structure reorganization. PMID:27455410

  19. Cadmium-induced cell death of basal forebrain cholinergic neurons mediated by muscarinic M1 receptor blockade, increase in GSK-3β enzyme, β-amyloid and tau protein levels.

    PubMed

    Del Pino, Javier; Zeballos, Gabriela; Anadón, María José; Moyano, Paula; Díaz, María Jesús; García, José Manuel; Frejo, María Teresa

    2016-05-01

    Cadmium is a neurotoxic compound which induces cognitive alterations similar to those produced by Alzheimer's disease (AD). However, the mechanism through which cadmium induces this effect remains unknown. In this regard, we described in a previous work that cadmium blocks cholinergic transmission and induces a more pronounced cell death on cholinergic neurons from basal forebrain which is partially mediated by AChE overexpression. Degeneration of basal forebrain cholinergic neurons, as happens in AD, results in memory deficits attributable to the loss of cholinergic modulation of hippocampal synaptic circuits. Moreover, cadmium has been described to activate GSK-3β, induce Aβ protein production and tau filament formation, which have been related to a selective loss of basal forebrain cholinergic neurons and development of AD. The present study is aimed at researching the mechanisms of cell death induced by cadmium on basal forebrain cholinergic neurons. For this purpose, we evaluated, in SN56 cholinergic mourine septal cell line from basal forebrain region, the cadmium toxic effects on neuronal viability through muscarinic M1 receptor, AChE splice variants, GSK-3β enzyme, Aβ and tau proteins. This study proves that cadmium induces cell death on cholinergic neurons through blockade of M1 receptor, overexpression of AChE-S and GSK-3β, down-regulation of AChE-R and increase in Aβ and total and phosphorylated tau protein levels. Our present results provide new understanding of the mechanisms contributing to the harmful effects of cadmium on cholinergic neurons and suggest that cadmium could mediate these mechanisms by M1R blockade through AChE splices altered expression.

  20. Antisense miR-132 blockade via the AChE-R splice variant mitigates cortical inflammation

    PubMed Central

    Mishra, Nibha; Friedson, Lyndon; Hanin, Geula; Bekenstein, Uriya; Volovich, Meshi; Bennett, Estelle R.; Greenberg, David S.; Soreq, Hermona

    2017-01-01

    MicroRNA (miR)-132 brain-to-body messages suppress inflammation by targeting acetylcholinesterase (AChE), but the target specificity of 3’-AChE splice variants and the signaling pathways involved remain unknown. Using surface plasmon resonance (SPR), we identified preferential miR-132 targeting of soluble AChE-R over synaptic-bound AChE-S, potentiating miR-132-mediated brain and body cholinergic suppression of pro-inflammatory cytokines. Inversely, bacterial lipopolysaccharide (LPS) reduced multiple miR-132 targets, suppressed AChE-S more than AChE-R and elevated inflammatory hallmarks. Furthermore, blockade of peripheral miR-132 by chemically protected AM132 antisense oligonucleotide elevated muscle AChE-R 10-fold over AChE-S, and cortical miRNA-sequencing demonstrated inverse brain changes by AM132 and LPS in immune-related miRs and neurotransmission and cholinergic signaling pathways. In neuromuscular junctions, AM132 co-elevated the nicotinic acetylcholine receptor and AChE, re-balancing neurotransmission and reaching mild muscle incoordination. Our findings demonstrate preferential miR-132-induced modulation of AChE-R which ignites bidirectional brain and body anti-inflammatory regulation, underscoring splice-variant miR-132 specificity as a new complexity level in inflammatory surveillance. PMID:28209997

  1. Peroxisome proliferator-activated receptor delta activation leads to increased transintestinal cholesterol efflux

    PubMed Central

    Vrins, Carlos L. J.; van der Velde, Astrid E.; van den Oever, Karin; Levels, Johannes H. M.; Huet, Stephane; Oude Elferink, Ronald P. J.; Kuipers, Folkert; Groen, Albert K.

    2009-01-01

    Peroxisome proliferator-activated receptor delta (PPARδ) is involved in regulation of energy homeostasis. Activation of PPARδ markedly increases fecal neutral sterol secretion, the last step in reverse cholesterol transport. This phenomenon can neither be explained by increased hepatobiliary cholesterol secretion, nor by reduced cholesterol absorption. To test the hypothesis that PPARδ activation leads to stimulation of transintestinal cholesterol efflux (TICE), we quantified it by intestine perfusions in FVB mice treated with PPARδ agonist GW610742. To exclude the effects on cholesterol absorption, mice were also treated with cholesterol absorption inhibitor ezetimibe or ezetimibe/GW610742. GW601742 treatment had little effect on plasma lipid levels but stimulated both fecal neutral sterol excretion (∼200%) and TICE (∼100%). GW610742 decreased intestinal Npc1l1 expression but had no effect on Abcg5/Abcg8. Interestingly, expression of Rab9 and LIMPII, encoding proteins involved in intracellular cholesterol trafficking, was increased upon PPARδ activation. Although treatment with ezetimibe alone had no effect on TICE, it reduced the effect of GW610742 on TICE. These data show that activation of PPARδ stimulates fecal cholesterol excretion in mice, primarily by the two-fold increase in TICE, indicating that this pathway provides an interesting target for the development of drugs aiming at the prevention of atherosclerosis. PMID:19439761

  2. Development of M1 mAChR Allosteric and Bitopic Ligands: Prospective Therapeutics for the Treatment of Cognitive Deficits

    PubMed Central

    2013-01-01

    Since the cholinergic hypothesis of memory dysfunction was first reported, extensive research efforts have focused on elucidating the mechanisms by which this intricate system contributes to the regulation of processes such as learning, memory, and higher executive function. Several cholinergic therapeutic targets for the treatment of cognitive deficits, psychotic symptoms, and the underlying pathophysiology of neurodegenerative disorders, such as Alzheimer’s disease and schizophrenia, have since emerged. Clinically approved drugs now exist for some of these targets; however, they all may be considered suboptimal therapeutics in that they produce undesirable off-target activity leading to side effects, fail to address the wide variety of symptoms and underlying pathophysiology that characterize these disorders, and/or afford little to no therapeutic effect in subsets of patient populations. A promising target for which there are presently no approved therapies is the M1 muscarinic acetylcholine receptor (M1 mAChR). Despite avid investigation, development of agents that selectively activate this receptor via the orthosteric site has been hampered by the high sequence homology of the binding site between the five muscarinic receptor subtypes and the wide distribution of this receptor family in both the central nervous system (CNS) and the periphery. Hence, a plethora of ligands targeting less structurally conserved allosteric sites of the M1 mAChR have been investigated. This Review aims to explain the rationale behind allosterically targeting the M1 mAChR, comprehensively summarize and critically evaluate the M1 mAChR allosteric ligand literature to date, highlight the challenges inherent in allosteric ligand investigation that are impeding their clinical advancement, and discuss potential methods for resolving these issues. PMID:23659787

  3. Development of M1 mAChR allosteric and bitopic ligands: prospective therapeutics for the treatment of cognitive deficits.

    PubMed

    Davie, Briana J; Christopoulos, Arthur; Scammells, Peter J

    2013-07-17

    Since the cholinergic hypothesis of memory dysfunction was first reported, extensive research efforts have focused on elucidating the mechanisms by which this intricate system contributes to the regulation of processes such as learning, memory, and higher executive function. Several cholinergic therapeutic targets for the treatment of cognitive deficits, psychotic symptoms, and the underlying pathophysiology of neurodegenerative disorders, such as Alzheimer's disease and schizophrenia, have since emerged. Clinically approved drugs now exist for some of these targets; however, they all may be considered suboptimal therapeutics in that they produce undesirable off-target activity leading to side effects, fail to address the wide variety of symptoms and underlying pathophysiology that characterize these disorders, and/or afford little to no therapeutic effect in subsets of patient populations. A promising target for which there are presently no approved therapies is the M1 muscarinic acetylcholine receptor (M1 mAChR). Despite avid investigation, development of agents that selectively activate this receptor via the orthosteric site has been hampered by the high sequence homology of the binding site between the five muscarinic receptor subtypes and the wide distribution of this receptor family in both the central nervous system (CNS) and the periphery. Hence, a plethora of ligands targeting less structurally conserved allosteric sites of the M1 mAChR have been investigated. This Review aims to explain the rationale behind allosterically targeting the M1 mAChR, comprehensively summarize and critically evaluate the M1 mAChR allosteric ligand literature to date, highlight the challenges inherent in allosteric ligand investigation that are impeding their clinical advancement, and discuss potential methods for resolving these issues.

  4. ROFA INCREASES CASPASE-3 ACTIVITY IN HUMAN ALVEOLAR MACRAPHAGE

    EPA Science Inventory

    Exposure to air pollution particles produces pulmonary inflammation and injury, but the mechanisms of this injury are unclear. Apoptosis, involving activation of caspases, may be one potential mechanism. In this study, we hypothesized that ROFA, a constituent of air pollution...

  5. Different enzymatic activities in carp (cyprinus carpio L.) as potential biomarkers of exposure to the pesticide methomyl.

    PubMed

    Hernández-Moreno, David; de la Casa-Resino, Irene; Maria Flores, José; González-Gómez, Manuel José; María Neila, Carlos; Soler, Francisco; Pérez-López, Marcos

    2014-09-29

    This study investigated the influence of the pesticide methomyl on different enzymatic activities in carp. The fish were exposed to a sub-lethal concentration (0.34 mg L-1) of methomyl for 15 days. On days 4 and 15, catalase (CAT) and glutathione-S-transferase (GST) activities were measured in the liver and gills. Acetylcholinesterase (AChE) activity in brain and muscle was also determined. Liver catalase activity slightly increased in exposed fish when compared to controls, but it was statistically significant only at the beginning of the experiment. No changes in CAT activity in the gills of exposed and control animals were observed (mean values were in the range 10.7-11.7 nmol min-1 per mg of protein). Liver GST activity was slightly inhibited in the exposed animals at the beginning of the study; however, it was significantly inhibited in the gills. Brain AChE activity was diminished throughout the experiment and significantly decreased after 96 h of exposure compared to controls (0.041 vs. 0.075 nmol min1 per mg of protein; p<0.001). Our findings suggest that CAT, GST, and AChE are reliable biomarkers of effect after exposure to methomyl.

  6. State Legislation Related to Increasing Physical Activity: 2006-2012

    PubMed Central

    Eyler, Amy A.; Budd, Elizabeth; Camberos, Gabriela J.; Yan, Yan; Brownson, Ross C.

    2016-01-01

    Background Strategies to improve physical activity prevalence often include policy and environmental changes. State-level policies can be influential in supporting access and opportunities for physical activity in schools and communities. The purpose of this study was to explore the prevalence of state legislation related to physical activity and identify the correlates of enactment of this legislation. Methods An online legislative database was used to collect bills from 50 states in the U.S. from 2006-2012 for ten topics related to physical activity. Bills were coded for content and compiled into a database with state-level variables (e.g., obesity prevalence). With enactment status as the outcome, bivariate and multivariate analyses were conducted. Results Of the 1542 bills related to physical activity introduced, 30% (N=460) were enacted. Bills on public transportation and trails were more likely to be enacted than those without these topics. Primary sponsorship by the Republican Party, bipartisan sponsorship, and mention of specific funding amounts were also correlates of enactment. Conclusion Policy surveillance of bills and correlates of enactment are important for understanding patterns in legislative support for physical activity. This information can be used to prioritize advocacy efforts and identify ways for research to better inform policy. PMID:26104603

  7. The Activity of Cholinesterases in Diapausing and Flying Red Mason Bees Osmia bicornis (Megachilidae).

    PubMed

    Dmochowska-Slezak, Kamila; Zaobidna, Ewa; Domeracka, Joanna; Swiatkowska, Marta; Rusznica, Małgorzata; Zółtowska, Krystyna

    2015-01-01

    The red mason bee (Osmia bicornis) is a highly effective pollinator that is exposed to various xenobiotics. The organism's potential resistance to the toxic effects of xenobiotics can be determined based on cholinesterase activity. The activity of cholinesterases (ChEs) towards acetylcholine (ACh) and butyrylcholine (BCh) was determined in extracts of diapausing (between October and late March) and flying bees (May). In both males and females, enzyme activity was higher towards ACh than towards BCh. The ratio of ACh/BCh activity was determined in the range of 1.43 to 4.15 in diapausing females and 3.00 to 7.18 in diapausing males. No significant changes in ChE activity towards ACh were observed in females before December and in males before February. Enzyme activity towards ACh increased dynamically in the second half of March. Enzyme activity towards BCh remained stable in both sexes until mid-March, after which it increased significantly. Excluding mid-March, enzyme BCh activity was significantly higher in females than in males. The activity of carboxylesterase towards 4-p-nitrophenyl butyrate was determined in females to assess the involvement of non-specific esterases in the hydrolysis of choline esters. Carboxylesterase activity was low in comparison with cholinesterase activity, and it remained practically unchanged throughout diapause, suggesting that choline esters in female O. bicornis extracts were hydrolyzed mainly by acetylcholinesterases.

  8. The Effects of Repeated Sub-Toxic Sarin Exposure on Behavior, EEG and Blood and Brain AChE Activity

    DTIC Science & Technology

    2005-08-01

    patterns in the common marmoset when followed for up to 15 months (one dose, 2.5-3.0 µg/kg sarin, i.m.). Interestingly, as with the current study...cognitive behavior and the electroencephalogram in the common marmoset . J Psychopharmacol. 1999; 13(2): 128-135. (41) Prendergast MA, Terry, AV Jr

  9. Reporter mutation studies show that nicotinic acetylcholine receptor (nAChR) α5 Subunits and/or variants modulate function of α6*-nAChR.

    PubMed

    Dash, Bhagirathi; Chang, Yongchang; Lukas, Ronald J

    2011-11-04

    To further the understanding of functional α6α5*-nicotinic acetylcholine receptors (nAChR; the asterisk (*) indicates known or possible presence of other subunits), we have heterologously expressed in oocytes different, mouse or human, nAChR subunit combinations. Coexpression with wild-type α5 subunits or chimeric α5/β3 subunits (in which the human α5 subunit N-terminal, extracellular domain is linked to the remaining domains of the human β3 subunit) almost completely abolishes the very small amount of function seen for α6β4*-nAChR and does not induce function of α6β2*-nAChR. Coexpression with human α5(V9)'(S) subunits bearing a valine 290 to serine mutation in the 9' position of the second transmembrane domain does not rescue the function of α6β4*-nAChR or induce function of α6β2*-nAChR. However, coexpression with mutant chimeric α5/β3(V9)'(S) subunits has a gain-of-function effect (higher functional expression and agonist sensitivity and spontaneous opening inhibited by mecamylamine) on α6β4*-nAChR. Moreover, N143D + M145V mutations in the α6 subunit N-terminal domain enable α5/β3(V9)'(S) subunits to have a gain-of-function effect on α6β2*-nAChR. nAChR containing chimeric α6/α3 subunits plus either β2 or β4 subunits have some function that is modulated in the presence of α5 or α5/β3 subunits. Coexpression with α5/β3(V9)'(S) subunits has a gain-of-function effect more pronounced than that in the presence of α5(V9)'(S) subunits. Gain-of-function effects are dependent, sometimes subtly, on the nature and apparently the extracellular, cytoplasmic, and/or transmembrane domain topology of partner subunits. These studies yield insight into assembly of functional α6α5*-nAChR and provide tools for development of α6*-nAChR-selective ligands that could be important in the treatment of nicotine dependence, and perhaps other neurological diseases.

  10. Hypothyroidism Enhanced Ectonucleotidases and Acetylcholinesterase Activities in Rat Synaptosomes can be Prevented by the Naturally Occurring Polyphenol Quercetin.

    PubMed

    Baldissarelli, Jucimara; Santi, Adriana; Schmatz, Roberta; Abdalla, Fátima Husein; Cardoso, Andréia Machado; Martins, Caroline Curry; Dias, Glaecir R Mundstock; Calgaroto, Nicéia Spanholi; Pelinson, Luana Paula; Reichert, Karine Paula; Loro, Vania Lucia; Morsch, Vera Maria Melchiors; Schetinger, Maria Rosa Chitolina

    2017-01-01

    Thyroid hormones have an influence on the functioning of the central nervous system. Furthermore, the cholinergic and purinergic systems also are extensively involved in brain function. In this context, quercetin is a polyphenol with antioxidant and neuroprotective properties. This study investigated the effects of (MMI)-induced hypothyroidism on the NTPDase, 5'-nucleotidase, adenosine deaminase (ADA), and acetylcholinesterase (AChE) activities in synaptosomes of rats and whether the quercetin can prevent it. MMI at a concentration of 20 mg/100 mL was administered for 90 days in the drinking water. The animals were divided into six groups: control/water (CT/W), control/quercetin 10 mg/kg, control/quercetin 25 mg/kg, methimazole/water (MMI/W), methimazole/quercetin 10 mg/kg (MMI/Q10), and methimazole/quercetin 25 mg/kg (MMI/Q25). On the 30th day, hormonal dosing was performed to confirm hypothyroidism, and the animals were subsequently treated with 10 or 25 mg/kg quercetin for 60 days. NTPDase activity was not altered in the MMI/W group. However, treatment with quercetin decreased ATP and ADP hydrolysis in the MMI/Q10 and MMI/Q25 groups. 5'-nucleotidase activity increased in the MMI/W group, but treatments with 10 or 25 mg/kg quercetin decreased 5'-nucleotidase activity. ADA activity decreased in the CT/25 and MMI/Q25 groups. Furthermore, AChE activity was reduced in all groups with hypothyroidism. In vitro tests also demonstrated that quercetin per se decreased NTPDase, 5'-nucleotidase, and AChE activities. This study demonstrated changes in the 5'-nucleotidase and AChE activities indicating that purinergic and cholinergic neurotransmission are altered in this condition. In addition, quercetin can alter these parameters and may be a promising natural compound with important neuroprotective actions in hypothyroidism.

  11. Dipeptides Increase Functional Activity of Human Skin Fibroblasts.

    PubMed

    Malinin, V V; Durnova, A O; Polyakova, V O; Kvetnoi, I M

    2015-05-01

    We analyzed the effect of dipeptide Glu-Trp and isovaleroyl-Glu-Trp in concentrations of 0.2, 2 and 20 μg/ml and Actovegin preparation on functional activity of human skin fibroblasts. Dipeptides, especially Glu-Trp, produce a stimulating effect on human skin fibroblasts and their effect is equivalent to that of Actovegin. Dipeptides stimulate cell renewal processes by activating synthesis of Ki-67 and reducing expression of caspase-9 and enhance antioxidant function of the cells by stimulating the expression of Hsp-90 and inducible NO-synthase. These findings suggest that dipeptides are promising candidates for preparations stimulating reparative processes.

  12. Unbalanced acetylcholinesterase activity in larynx squamous cell carcinoma.

    PubMed

    Castillo-González, Ana Cristina; Pelegrín-Hernández, Juan Pablo; Nieto-Cerón, Susana; Madrona, Antonio Piñero; Noguera, José Antonio; López-Moreno, María Fuensanta; Rodríguez-López, José Neptuno; Vidal, Cecilio J; Hellín-Meseguer, Diego; Cabezas-Herrera, Juan

    2015-11-01

    Previous reports have demonstrated that a non-neuronal cholinergic system is expressed aberrantly in airways. A proliferative effect is exerted directly by cholinergic agonists through the activation of nicotinic and muscarinic receptors. In cancer, particularly those related with smoking, the mechanism through which tumour cells respond to aberrantly activated cholinergic signalling is a key question. Fifty paired pieces of larynx squamous cell carcinoma and adjacent non-cancerous tissue were compared in terms of their acetylcholinesterase activity (AChE). The AChE activity in non-cancerous tissues (0.248 ± 0.030 milliunits per milligram of wet tissue; mU/mg) demonstrates that upper respiratory tissues express sufficient AChE activity for controlling the level of acetylcholine (ACh). In larynx carcinomas, the AChE activity decreased to 0.157 ± 0.024 mU/mg (p=0.009). Larynx cancer patients exhibiting low ACh-degrading enzymatic activity had a significantly shorter overall survival (p=0.031). Differences in the mRNA levels of alternatively spliced AChE isoforms and molecular compositions were noted between glottic and supraglottic cancers. Our results suggest that the low AChE activity observed in larynx squamous cell carcinoma may be useful for predicting the outcome of patients.

  13. Morphine Increases Acetylcholine Release in the Trigeminal Nuclear Complex

    PubMed Central

    Zhu, Zhenghong; Bowman, Heather R.; Baghdoyan, Helen A.; Lydic, Ralph

    2008-01-01

    Study Objectives: The trigeminal nuclear complex (V) contains cholinergic neurons and includes the principal sensory trigeminal nucleus (PSTN) which receives sensory input from the face and jaw, and the trigeminal motor nucleus (MoV) which innervates the muscles of mastication. Pain associated with pathologies of V is often managed with opioids but no studies have characterized the effect of opioids on acetylcholine (ACh) release in PSTN and MoV. Opioids can increase or decrease ACh release in brainstem nuclei. Therefore, the present experiments tested the 2-tailed hypothesis that microdialysis delivery of opioids to the PSTN and MoV significantly alters ACh release. Design: Using a within-subjects design and isoflurane-anesthetized Wistar rats (n = 53), ACh release in PSTN during microdialysis with Ringer's solution (control) was compared to ACh release during dialysis delivery of the sodium channel blocker tetrodotoxin, muscarinic agonist bethanechol, opioid agonist morphine, mu opioid agonist DAMGO, antagonists for mu (naloxone) and kappa (nor-binaltorphimine; nor-BNI) opioid receptors, and GABAA antagonist bicuculline. Measurements and Results: Tetrodotoxin decreased ACh, confirming action potential-dependent ACh release. Bethanechol and morphine caused a concentration-dependent increase in PSTN ACh release. The morphine-induced increase in ACh release was blocked by nor-BNI but not by naloxone. Bicuculline delivered to the PSTN also increased ACh release. ACh release in the MoV was increased by morphine, and this increase was not blocked by naloxone or nor-BNI. Conclusions: These data comprise the first direct measures of ACh release in PSTN and MoV and suggest synaptic disinhibition as one possible mechanism by which morphine increases ACh release in the trigeminal nuclei. Citation: Zhu Z; Bowman HR; Baghdoyan HA; Lydic R. Morphine increases acetylcholine release in the trigeminal nuclear complex. SLEEP 2008;31(12):1629–1637. PMID:19090318

  14. Nicotine increases GABAergic input on rat dorsal raphe serotonergic neurons through alpha7 nicotinic acetylcholine receptor.

    PubMed

    Hernández-Vázquez, F; Chavarría, K; Garduño, J; Hernández-López, S; Mihailescu, S P

    2014-12-15

    The dorsal raphe nucleus (DRN) contains large populations of serotonergic (5-HT) neurons. This nucleus receives GABAergic inhibitory afferents from many brain areas and from DRN interneurons. Both GABAergic and 5-HT DRN neurons express functional nicotinic acetylcholine receptors (nAChRs). Previous studies have demonstrated that nicotine increases 5-HT release and 5-HT DRN neuron discharge rate by stimulating postsynaptic nAChRs and by increasing glutamate and norepinephrine release inside DRN. However, the influence of nicotine on the GABAergic input to 5-HT DRN neurons was poorly investigated. Therefore, the aim of this work was to determine the effect of nicotine on GABAergic spontaneous inhibitory postsynaptic currents (sIPSCs) of 5-HT DRN neurons and the subtype of nAChR(s) involved in this response. Experiments were performed in coronal slices obtained from young Wistar rats. GABAergic sIPSCs were recorded from post hoc-identified 5-HT DRN neurons with the whole cell voltage patch-clamp technique. Administration of nicotine (1 μM) increased sIPSC frequency in 72% of identified 5-HT DRN neurons. This effect was not reproduced by the α4β2 nAChR agonist RJR-2403 and was not influenced by TTX (1 μM). It was mimicked by the selective agonist for α7 nAChR, PNU-282987, and exacerbated by the positive allosteric modulator of the same receptor, PNU-120596. The nicotine-induced increase in sIPSC frequency was independent on voltage-gated calcium channels and dependent on Ca(2+)-induced Ca(2+) release (CICR). These results demonstrate that nicotine increases the GABAergic input to most 5-HT DRN neurons, by activating α7 nAChRs and producing CICR in DRN GABAergic terminals.

  15. BMS-933043, a Selective α7 nAChR Partial Agonist for the Treatment of Cognitive Deficits Associated with Schizophrenia.

    PubMed

    King, Dalton; Iwuagwu, Christiana; Cook, Jim; McDonald, Ivar M; Mate, Robert; Zusi, F Christopher; Hill, Matthew D; Fang, Haiquan; Zhao, Rulin; Wang, Bei; Easton, Amy E; Miller, Regina; Post-Munson, Debra; Knox, Ronald J; Gallagher, Lizbeth; Westphal, Ryan; Molski, Thaddeus; Fan, Jingsong; Clarke, Wendy; Benitex, Yulia; Lentz, Kimberley A; Denton, Rex; Morgan, Daniel; Zaczek, Robert; Lodge, Nicholas J; Bristow, Linda J; Macor, John E; Olson, Richard E

    2017-03-09

    The therapeutic treatment of negative symptoms and cognitive dysfunction associated with schizophrenia is a significant unmet medical need. Preclinical literature indicates that α7 neuronal nicotinic acetylcholine (nACh) receptor agonists may provide an effective approach to treating cognitive dysfunction in schizophrenia. We report herein the discovery and evaluation of 1c (BMS-933043), a novel and potent α7 nACh receptor partial agonist with high selectivity against other nicotinic acetylcholine receptor subtypes (>100-fold) and the 5-HT3A receptor (>300-fold). In vivo activity was demonstrated in a preclinical model of cognitive impairment, mouse novel object recognition. BMS-933043 has completed Phase I clinical trials.

  16. Soil disturbance increases soil microbial enzymatic activity in arid ecoregion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Functional diversity of the soil microbial community is commonly used in the assessment of soil health as it relates to the activity of soil microflora involved in carbon cycling. Soil microbes in different microenvironments will have varying responses to different substrates, thus catabolic fingerp...

  17. Increasing Pupil Physical Activity: A Comprehensive Professional Development Effort

    ERIC Educational Resources Information Center

    Kulinna, Pamela Hodges

    2012-01-01

    Study aim: To determine if pupil physical activity and Body Mass Index classifications maintained or improved after a one-year professional development program involving both classroom and physical education teachers. Guskey's model of teacher change guided this study. Material and methods: Indigenous children from ten schools (N = 320) in grades…

  18. Texting to increase physical activity in teens: Development & preliminary

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our purpose was to present formative research and preliminary results for a self-determination-theory (SDT)-based text messages to promote physical activity (PA) among teens. Thirty 14- to 17-year olds, stratified by gender and race/ethnicity (Black, Hispanic, White), were recruited to participate i...

  19. Increasing Physical Activity of Children during School Recess

    ERIC Educational Resources Information Center

    Hayes, Lynda B.; Van Camp, Carole M.

    2015-01-01

    Physical activity is crucial for children's health. Fitbit accelerometers were used to measure steps of 6 elementary students during recess. The intervention included reinforcement, self-monitoring, goal setting, and feedback. Steps taken during the intervention phase (M?=?1,956 steps) were 47% higher than in baseline (M?=?1,326 steps), and the…

  20. Somatosensory Anticipatory Alpha Activity Increases to Suppress Distracting Input

    ERIC Educational Resources Information Center

    Haegens, Saskia; Luther, Lisa; Jensen, Ole

    2012-01-01

    Effective processing of sensory input in daily life requires attentional selection and amplification of relevant input and, just as importantly, attenuation of irrelevant information. It has been proposed that top-down modulation of oscillatory alpha band activity (8-14 Hz) serves to allocate resources to various regions, depending on task…

  1. Activation of Transient Receptor Potential Vanilloid 4 Increases NMDA-Activated Current in Hippocampal Pyramidal Neurons

    PubMed Central

    Li, Lin; Qu, Weijun; Zhou, Libin; Lu, Zihong; Jie, Pinghui; Chen, Lei; Chen, Ling

    2013-01-01

    The glutamate excitotoxicity, mediated through N-methyl-d-aspartate receptors (NMDARs), plays an important role in cerebral ischemia injury. Transient receptor potential vanilloid 4 (TRPV4) can be activated by multiple stimuli that may happen during stroke. The present study evaluated the effect of TRPV4 activation on NMDA-activated current (INMDA) and that of blocking TRPV4 on brain injury after focal cerebral ischemia in mice. We herein report that activation of TRPV4 by 4α-PDD and hypotonic stimulation increased INMDA in hippocampal CA1 pyramidal neurons, which was sensitive to TRPV4 antagonist HC-067047 and NMDAR antagonist AP-5, indicating that TRPV4 activation potentiates NMDAR response. In addition, the increase in INMDA by hypotonicity was sensitive to the antagonist of NMDAR NR2B subunit, but not of NR2A subunit. Furthermore, antagonists of calcium/calmodulin-dependent protein kinase II (CaMKII) significantly attenuated hypotonicity-induced increase in INMDA, while antagonists of protein kinase C or casein kinase II had no such effect, indicating that phosphorylation of NR2B subunit by CaMKII is responsible for TRPV4-potentiated NMDAR response. Finally, we found that intracerebroventricular injection of HC-067047 after 60 min middle cerebral artery occlusion reduced the cerebral infarction with at least a 12 h efficacious time-window. These findings indicate that activation of TRPV4 increases NMDAR function, which may facilitate glutamate excitotoxicity. Closing TRPV4 may exert potent neuroprotection against cerebral ischemia injury through many mechanisms at least including the prevention of NMDAR-mediated glutamate excitotoxicity. PMID:23459987

  2. T Lymphocyte Activation Threshold is Increased in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Adams, Charley L.; Gonzalez, M.; Sams, C. F.

    2000-01-01

    There have been substantial advances in molecular and cellular biology that have provided new insight into the biochemical and genetic basis of lymphocyte recognition, activation and expression of distinct functional phenotypes. It has now become evident that for both T and B cells, stimuli delivered through their receptors can result in either clonal expansion or apoptosis. In the case of T cells, clonal expansion of helper cells is accompanied by differentiation into two major functional subsets which regulate the immune response. The pathways between the membrane and the nucleus and their molecular components are an area of very active investigation. This meeting will draw together scientists working on diverse aspects of this problem, including receptor ligand interactions, intracellular pathways that transmit receptor mediated signals and the effect of such signal transduction pathways on gene regulation. The aim of this meeting is to integrate the information from these various experimental approaches into a new synthesis and molecular explanation of T cell activation, differentiation and death.

  3. A positive allosteric modulator of α7 nAChRs augments neuroprotective effects of endogenous nicotinic agonists in cerebral ischaemia

    PubMed Central

    Kalappa, Bopanna I; Sun, Fen; Johnson, Stephen R; Jin, Kunlin; Uteshev, Victor V

    2013-01-01

    Background and Purpose Activation of α7 nicotinic acetylcholine receptors (nAChRs) can be neuroprotective. However, endogenous choline and ACh have not been regarded as potent neuroprotective agents because physiological levels of choline/ACh do not produce neuroprotective levels of α7 activation. This limitation may be overcome by the use of type-II positive allosteric modulators (PAMs-II) of α7 nAChRs, such as 1-(5-chloro-2,4-dimethoxyphenyl)-3-(5-methylisoxazol-3-yl)-urea (PNU-120596). This proof-of-concept study presents a novel neuroprotective paradigm that converts endogenous choline/ACh into potent neuroprotective agents in cerebral ischaemia by inhibiting α7 nAChR desensitization using PNU-120596. Experimental Approach An electrophysiological ex vivo cell injury assay (to quantify the susceptibility of hippocampal neurons to acute injury by complete oxygen and glucose deprivation; COGD) and an in vivo middle cerebral artery occlusion model of ischaemia were used in rats. Key Results Choline (20–200 μM) in the presence, but not absence of 1 μM PNU-120596 significantly delayed anoxic depolarization/injury of hippocampal CA1 pyramidal neurons, but not CA1 stratum radiatum interneurons, subjected to COGD in acute hippocampal slices and these effects were blocked by 20 nM methyllycaconitine, a selective α7 antagonist, thus, activation of α7 nAChRs was required. PNU-120596 alone was ineffective ex vivo. In in vivo experiments, both pre- and post-ischaemia treatments with PNU-120596 (30 mg·kg−1, s.c. and 1 mg·kg−1, i.v., respectively) significantly reduced the cortical/subcortical infarct volume caused by transient focal cerebral ischaemia. PNU-120596 (1 mg·kg−1, i.v., 30 min post-ischaemia) remained neuroprotective in rats subjected to a choline-deficient diet for 14 days prior to experiments. Conclusions and Implications PNU-120596 and possibly other PAMs-II significantly improved neuronal survival in cerebral ischaemia by augmenting

  4. Roles for N-terminal extracellular domains of nicotinic acetylcholine receptor (nAChR) β3 subunits in enhanced functional expression of mouse α6β2β3- and α6β4β3-nAChRs.

    PubMed

    Dash, Bhagirathi; Li, Ming D; Lukas, Ronald J

    2014-10-10

    Functional heterologous expression of naturally expressed mouse α6*-nicotinic acetylcholine receptors (mα6*-nAChRs; where "*" indicates the presence of additional subunits) has been difficult. Here we expressed and characterized wild-type (WT), gain-of-function, chimeric, or gain-of-function chimeric nAChR subunits, sometimes as hybrid nAChRs containing both human (h) and mouse (m) subunits, in Xenopus oocytes. Hybrid mα6mβ4hβ3- (∼ 5-8-fold) or WT mα6mβ4mβ3-nAChRs (∼ 2-fold) yielded higher function than mα6mβ4-nAChRs. Function was not detected when mα6 and mβ2 subunits were expressed together or in the additional presence of hβ3 or mβ3 subunits. However, function emerged upon expression of mα6mβ2mβ3(V9'S)-nAChRs containing β3 subunits having gain-of-function V9'S (valine to serine at the 9'-position) mutations in transmembrane domain II and was further elevated 9-fold when hβ3(V9'S) subunits were substituted for mβ3(V9'S) subunits. Studies involving WT or gain-of-function chimeric mouse/human β3 subunits narrowed the search for domains that influence functional expression of mα6*-nAChRs. Using hβ3 subunits as templates for site-directed mutagenesis studies, substitution with mβ3 subunit residues in extracellular N-terminal domain loops "C" (Glu(221) and Phe(223)), "E" (Ser(144) and Ser(148)), and "β2-β3" (Gln(94) and Glu(101)) increased function of mα6mβ2*- (∼ 2-3-fold) or mα6mβ4* (∼ 2-4-fold)-nAChRs. EC50 values for nicotine acting at mα6mβ4*-nAChR were unaffected by β3 subunit residue substitutions in loop C or E. Thus, amino acid residues located in primary (loop C) or complementary (loops β2-β3 and E) interfaces of β3 subunits are some of the molecular impediments for functional expression of mα6mβ2β3- or mα6mβ4β3-nAChRs.

  5. Density increase due to active feedback in mirror machine

    NASA Astrophysics Data System (ADS)

    Seemann, Omri; Be'Ery, Ilan

    2014-10-01

    Mirror machines are one of the schemes for future fusion systems. Its main drawbacks are the flute instability and being open ended which results in plasma losses. A feedback system is used to stabilize the flute instability in a table top mirror machine with a continuous plasma source and RF heating. Under certain source density and temperature conditions, although the plasma was stabilized, plasma density increase was not measured. After decreasing the source density and increasing the temperature, Plasma density increase was achieved. It is theorized that these results are due to transition of the plasma main loss mechanism from collision dominated to instability dominated. In the former, the main density loss is through diffusion and In the latter, it is through flute instability which drives the plasma to the edge of the vacuum chamber. Future research directions are discussed for a planned machine which should achieve higher temperatures and better diagnostic capabilities. The research will focus on magnetic actuators and passive RF stabilization.

  6. Anniston Community Health Survey: Follow-Up and Dioxin Analyses (ACHS-II) - Methods

    PubMed Central

    Birnbaum, L.S.; Dutton, N.D.; Cusack, C.; Mennemeyer, S.T.; Pavuk, M.

    2015-01-01

    High serum concentrations of polychlorinated biphenyls (PCBs) have been reported previously among residents of Anniston, Alabama, where a PCB production facility was located in the past. As the second of two cross-sectional studies of these Anniston residents, the Anniston Community Health Survey: Follow-Up and Dioxin Analyses (ACHS-II) will yield repeated measurements to be used to evaluate changes over time in ortho-PCB concentrations and selected health indicators in study participants. Dioxins, non-ortho PCBs, other chemicals, heavy metals, and a variety of additional clinical tests not previously measured in the original ACHS cohort will be examined in ACHS-II. The follow-up study also incorporates a questionnaire with extended sections on diet and occupational history for a more comprehensive assessment of possible exposure sources. Data collection for ACHS-II from 359 eligible participants took place in 2014, seven to nine years after ACHS. PMID:25982988

  7. Anniston community health survey: Follow-up and dioxin analyses (ACHS-II)--methods.

    PubMed

    Birnbaum, Linda S; Dutton, N D; Cusack, C; Mennemeyer, S T; Pavuk, M

    2016-02-01

    High serum concentrations of polychlorinated biphenyls (PCBs) have been reported previously among residents of Anniston, Alabama, where a PCB production facility was located in the past. As the second of two cross-sectional studies of these Anniston residents, the Anniston Community Health Survey: Follow-Up and Dioxin Analyses (ACHS-II) will yield repeated measurements to be used to evaluate changes over time in ortho-PCB concentrations and selected health indicators in study participants. Dioxins, non-ortho PCBs, other chemicals, heavy metals, and a variety of additional clinical tests not previously measured in the original ACHS cohort will be examined in ACHS-II. The follow-up study also incorporates a questionnaire with extended sections on diet and occupational history for a more comprehensive assessment of possible exposure sources. Data collection for ACHS-II from 359 eligible participants took place in 2014, 7 to 9 years after ACHS.

  8. Development and validation of a sample stabilization strategy and a UPLC-MS/MS method for the simultaneous quantitation of acetylcholine (ACh), histamine (HA), and its metabolites in rat cerebrospinal fluid (CSF).

    PubMed

    Zhang, Yanhua; Tingley, F David; Tseng, Elaine; Tella, Max; Yang, Xin; Groeber, Elizabeth; Liu, Jianhua; Li, Wenlin; Schmidt, Christopher J; Steenwyk, Rick

    2011-07-15

    A UPLC-MS/MS assay was developed and validated for simultaneous quantification of acetylcholine (ACh), histamine (HA), tele-methylhistamine (t-mHA), and tele-methylimidazolacetic acid (t-MIAA) in rat cerebrospinal fluid (CSF). The biological stability of ACh in rat CSF was investigated. Following fit-for-purpose validation, the method was applied to monitor the drug-induced changes in ACh, HA, t-mHA, and t-MIAA in rat CSF following administration of donepezil or prucalopride. The quantitative method utilizes hydrophilic interaction chromatography (HILIC) Core-Shell HPLC column technology and a UPLC system to achieve separation with detection by positive ESI LC-MS/MS. This UPLC-MS/MS method does not require extraction or derivatization, utilizes a stable isotopically labeled internal standard (IS) for each analyte, and allows for rapid throughput with a 4 min run time. Without an acetylcholinesterase (AChE) inhibitor present, ACh was found to have 1.9±0.4 min in vitro half life in rat CSF. Stability studies and processing modification, including the use of AChE inhibitor eserine, extended this half life to more than 60 min. The UPLC-MS/MS method, including stabilization procedure, was validated over a linear concentration range of 0.025-5 ng/mL for ACh and 0.05-10 ng/mL for HA, t-mHA, and t-MIAA. The intra-run precision and accuracy for all analytes were 1.9-12.3% CV and -10.2 to 9.4% RE, respectively, while inter-run precision and accuracy were 4.0-16.0% CV and -5.3 to 13.4% RE, respectively. By using this developed and validated method, donepezil caused increases in ACh levels at 0.5, 1, 2, and 4h post dose as compared to the corresponding vehicle group, while prucalopride produced approximately 1.6- and 3.1-fold increases in the concentrations of ACh and t-mHA at 1h post dose, respectively, compared to the vehicle control. Overall, this methodology enables investigations into the use of CSF ACh and HA as biomarkers in the study of these neurotransmitter systems

  9. Copper acutely impairs behavioral function and muscle acetylcholinesterase activity in zebrafish (Danio rerio).

    PubMed

    Haverroth, Gabriela M B; Welang, Chariane; Mocelin, Riciéri N; Postay, Daniela; Bertoncello, Kanandra T; Franscescon, Francini; Rosemberg, Denis B; Dal Magro, Jacir; Dalla Corte, Cristiane L

    2015-12-01

    Copper is a heavy metal found at relatively high concentrations in surface waters around the world. Copper is a micronutrient at low concentrations and is essential to several organisms. At higher concentrations copper can become toxic, which reveal the importance of studying the toxic effects of this metal on the aquatic life. Thus, the objective of this study was to evaluate the toxic effects of copper on the behavior and biochemical parameters of zebrafish (Danio rerio). Zebrafish were exposed for 24h at a concentration of 0.006 mg/L Cu. After the exposure period, behavioral profile of animals was recorded through 6 min using two different apparatuses tests: the Novel Tank and the Light-Dark test. After behavioral testing, animals were euthanized with a solution of 250 mg/L of tricaine (MS-222). Brain, muscle, liver and gills were extracted for analysis of parameters related to oxidative stress and accumulation of copper in these tissues. Acetylcholinesterase (AChE) activity was determined in brain and muscle. Results showed acute exposure to copper induces significant changes in behavioral profile of zebrafish by changing locomotion and natural tendency to avoid brightly lit area. On the other hand, there were no significant effects on parameters related to oxidative stress. AChE activity decreased significantly in zebrafish muscle, but there were no significant changes in cerebral AChE activity. Copper levels in tissues did not increase significantly compared to the controls. Taken together, these results indicate that a low concentration of copper can acutely affect behavioral profile of adult zebrafish which could be partially related to an inhibition on muscle AChE activity. These results reinforce the need of additional tests to establishment of safe copper concentrations to aquatic organisms and the importance of behavioral parameters in ecotoxicological studies.

  10. Activity of cholinesterases, pyruvate kinase and adenosine deaminase in rats experimentally infected by Fasciola hepatica: Influences of these enzymes on inflammatory response and pathological findings.

    PubMed

    Baldissera, Matheus D; Bottari, Nathieli B; Mendes, Ricardo E; Schwertz, Claiton I; Lucca, Neuber J; Dalenogare, Diessica; Bochi, Guilherme V; Moresco, Rafael N; Morsch, Vera M; Schetinger, Maria R C; Rech, Virginia C; Jaques, Jeandre A; Da Silva, Aleksandro S

    2015-11-01

    The aim of this study was to investigate acetylcholinesterase (AChE) in total blood and liver tissue; butyrylcholinesterase (BChE) in serum and liver tissue; adenosine deaminase (ADA) in serum and liver tissue; and pyruvate kinase (PK) in liver tissue of rats experimentally infected by Fasciola hepatica. Animals were divided into two groups with 12 animals each, as follows: group A (uninfected) and group B (infected). Samples were collected at 20 (A1 and B1;n=6 each) and 150 (A2 and B2; n=6 each) days post-infection (PI). Infected animals showed an increase in AChE activity in whole blood and a decrease in AChE activity in liver homogenates (P<0.05) at 20 and 150 days PI. BChE and PK activities were decreased (P<0.05) in serum and liver homogenates of infected animals at 150 days PI. ADA activity was decreased in serum at 20 and 150 days PI, while in liver homogenates it was only decreased at 150 days PI (P<0.05). Aspartate aminotransferase and alanine aminotransferase activities in serum were increased (P<0.05), while concentrations of total protein and albumin were decreased (P<0.05) when compared to control. The histological analysis revealed fibrous perihepatitis and necrosis. Therefore, we conclude that the liver fluke is associated with cholinergic and purinergic dysfunctions, which in turn may influence the pathogenesis of the disease.

  11. Active commuting to school in Finland, the potential for physical activity increase in different seasons

    PubMed Central

    Kallio, Jouni; Turpeinen, Salla; Hakonen, Harto; Tammelin, Tuija

    2016-01-01

    Background Active commuting to school (ACS) can be a significant source of physical activity and provide many health benefits. Objective This study identified the potential to increase physical activity levels by promoting ACS in Finnish schools and evaluated the effects of season, distance and age on ACS. Design Data were collected with a questionnaire from 5,107 students, aged 10–16, in 45 comprehensive schools in Finland. The distance and the mode of transport to school in different seasons were self-reported. Results The prevalence of ACS was over 80% during spring/fall for those living 0–5 km from school. ACS was inversely associated with the distance to school and was lower in winter compared to spring and fall. Cycling is less common in winter, especially among girls and younger students. The potential for increasing students’ physical activity levels via ACS seems to be largest in winter, especially among students living 1–5 km from school. The variation in the prevalence of ACS between schools was large, especially in winter. Conclusions When planning interventions to promote ACS, one is encouraged to acknowledge and evaluate the potential in the selected target schools in different seasons. The potential varies largely between schools and seasons and is highly dependent on students’ commuting distances. PMID:27924739

  12. Increased intrathecal inflammatory activity in frontotemporal dementia: pathophysiological implications

    PubMed Central

    Sjogren, M; Folkesson, S; Blennow, K; Tarkowski, E

    2004-01-01

    Objective: Immunological mechanisms may be part of the pathophysiological mechanisms in frontotemporal dementia (FTD), but hitherto only vague evidence of such mechanisms has been presented. The aim of this study was to compare the cerebrospinal fluid (CSF) levels of the pro-inflammatory cytokines interleukin (IL)-1ß and tumour necrosis factor (TNF)-α, and the anti-inflammatory cytokine transforming growth factor (TGF)-ß in patients with FTD and normal controls. Furthermore, serum levels of TNF-α, TGF-ß, and IL-1ß were measured in FTD patients. Methods: The CSF levels of IL-1ß, TNFα, and TGF-ß were measured using ELISA in 19 patients with FTD and 24 sex and age matched healthy controls. Results: The CSF levels of TNF-α (FTD 0.6 pg/mL (median: lower, upper quartile 0.3, 0.7); controls: 0.0 pg/mL (0.0, 0.0); p = 0.008) and TGF-ß (FTD 266 pg/mL (157, 371), controls: 147 pg/mL (119, 156); p = 0.0001) were significantly increased in FTD patients compared with controls. No correlations were found between CSF and serum levels of the cytokines. In the controls, but not in the FTD patients, a positive correlation was found between the CSF levels of TGF-ß and age (r = 0.42, p<0.05). No correlation was found between any of the cytokines and degree of brain atrophy or white matter changes. No differences between the groups were found for age, gender, or CSF/serum albumin ratio. Conclusions: The results suggest an increased intrathecal production of both pro- and anti-inflammatory cytokines in FTD. As no correlations were found with the albumin ratio, and no correlations between CSF and serum levels of the cytokines were found, these changes in the CSF cannot be explained by a systemic overproduction of cytokines. PMID:15258209

  13. Maternal caffeine exposure alters neuromotor development and hippocampus acetylcholinesterase activity in rat offspring.

    PubMed

    Souza, Ana Claudia; Souza, Andressa; Medeiros, Liciane Fernandes; De Oliveira, Carla; Scarabelot, Vanessa Leal; Da Silva, Rosane Souza; Bogo, Mauricio Reis; Capiotti, Katiucia Marques; Kist, Luiza Wilges; Bonan, Carla D; Caumo, Wolnei; Torres, Iraci L S

    2015-01-21

    The objective of this study was to evaluate the effects of maternal caffeine intake on the neuromotor development of rat offspring and on acetylcholine degradation and acetylcholinesterase (AChE) expression in the hippocampus of 14-day-old infant rats. Rat dams were treated with caffeine (0.3g/L) throughout gestation and lactation until the pups were 14 days old. The pups were divided into three groups: (1) control, (2) caffeine, and (3) washout caffeine. The washout group received a caffeine solution until the seventh postnatal day (P7). Righting reflex (RR) and negative geotaxis (NG) were assessed to evaluate postural parameters as an index of neuromotor reflexes. An open-field (OF) test was conducted to assess locomotor and exploratory activities as well as anxiety-like behaviors. Caffeine treatment increased both RR and NG latency times. In the OF test, the caffeine group had fewer outer crossings and reduced locomotion compared to control, while the washout group showed increased inner crossings in relation to the other groups and fewer rearings only in comparison to the control group. We found decreased AChE activity in the caffeine group compared to the other groups, with no alteration in AChE transcriptional regulation. Chronic maternal exposure to caffeine promotes important alterations in neuromotor development. These results highlight the ability of maternal caffeine intake to interfere with cholinergic neurotransmission during brain development.

  14. Complexing Methylene Blue with Phosphorus Dendrimers to Increase Photodynamic Activity.

    PubMed

    Dabrzalska, Monika; Janaszewska, Anna; Zablocka, Maria; Mignani, Serge; Majoral, Jean Pierre; Klajnert-Maculewicz, Barbara

    2017-02-23

    The efficiency of photodynamic therapy is limited mainly due to low selectivity, unfavorable biodistribution of photosensitizers, and long-lasting skin sensitivity to light. However, drug delivery systems based on nanoparticles may overcome the limitations mentioned above. Among others, dendrimers are particularly attractive as carriers, because of their globular architecture and high loading capacity. The goal of the study was to check whether an anionic phosphorus dendrimer is suitable as a carrier of a photosensitizer-methylene blue (MB). As a biological model, basal cell carcinoma cell lines were used. We checked the influence of the MB complexation on its singlet oxygen production ability using a commercial fluorescence probe. Next, cellular uptake, phototoxicity, reactive oxygen species (ROS) generation, and cell death were investigated. The MB-anionic dendrimer complex (MB-1an) was found to generate less singlet oxygen; however, the complex showed higher cellular uptake and phototoxicity against basal cell carcinoma cell lines, which was accompanied with enhanced ROS production. Owing to the obtained results, we conclude that the photodynamic activity of MB complexed with an anionic dendrimer is higher than free MB against basal cell carcinoma cell lines.

  15. Increased Visual Stimulation Systematically Decreases Activity in Lateral Intermediate Cortex

    PubMed Central

    Nasr, Shahin; Stemmann, Heiko; Vanduffel, Wim; Tootell, Roger B. H.

    2015-01-01

    Previous studies have attributed multiple diverse roles to the posterior superior temporal cortex (STC), both visually driven and cognitive, including part of the default mode network (DMN). Here, we demonstrate a unifying property across this multimodal region. Specifically, the lateral intermediate (LIM) portion of STC showed an unexpected feature: a progressively decreasing fMRI response to increases in visual stimulus size (or number). Such responses are reversed in sign, relative to well-known responses in classic occipital temporal visual cortex. In LIM, this “reversed” size function was present across multiple object categories and retinotopic eccentricities. Moreover, we found a significant interaction between the LIM size function and the distribution of subjects' attention. These findings suggest that LIM serves as a part of the DMN. Further analysis of functional connectivity, plus a meta-analysis of previous fMRI results, suggests that LIM is a heterogeneous area including different subdivisions. Surprisingly, analogous fMRI tests in macaque monkeys did not reveal a clear homolog of LIM. This interspecies discrepancy supports the idea that self-referential thinking and theory of mind are more prominent in humans, compared with monkeys. PMID:25480358

  16. Increased Visual Stimulation Systematically Decreases Activity in Lateral Intermediate Cortex.

    PubMed

    Nasr, Shahin; Stemmann, Heiko; Vanduffel, Wim; Tootell, Roger B H

    2015-10-01

    Previous studies have attributed multiple diverse roles to the posterior superior temporal cortex (STC), both visually driven and cognitive, including part of the default mode network (DMN). Here, we demonstrate a unifying property across this multimodal region. Specifically, the lateral intermediate (LIM) portion of STC showed an unexpected feature: a progressively decreasing fMRI response to increases in visual stimulus size (or number). Such responses are reversed in sign, relative to well-known responses in classic occipital temporal visual cortex. In LIM, this "reversed" size function was present across multiple object categories and retinotopic eccentricities. Moreover, we found a significant interaction between the LIM size function and the distribution of subjects' attention. These findings suggest that LIM serves as a part of the DMN. Further analysis of functional connectivity, plus a meta-analysis of previous fMRI results, suggests that LIM is a heterogeneous area including different subdivisions. Surprisingly, analogous fMRI tests in macaque monkeys did not reveal a clear homolog of LIM. This interspecies discrepancy supports the idea that self-referential thinking and theory of mind are more prominent in humans, compared with monkeys.

  17. Anti-diabetic and anti-Alzheimer's disease activities of Angelica decursiva.

    PubMed

    Yousof Ali, Md; Jung, Hyun Ah; Choi, Jae Sue

    2015-12-01

    Diabetes mellitus (DM) and Alzheimer's disease (AD) constitute two global health issues. DM is an ever-increasing epidemic affecting millions of elderly people worldwide, causing major repercussions on patients' daily lives, mostly due to chronic complications. Complications from DM can affect the brain, thereby characterizing DM as a risk factor for AD. In the present study, we examined the inhibitory activity of methanol extracts of different parts of 12 Angelica species against α-glucosidase, protein tyrosine phosphatase 1B (PTP1B), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE). The methanol extract of Angelica decursiva exhibited the highest inhibitory activities against α-glucosidase, PTP1B, AChE, and BChE and so was selected for further investigation. Repeated column chromatography based on bioactivity-guided fractionation yielded seven compounds (1-7). Among these compounds, nodakenin (1), nodakenetin (2), umbelliferone (3), cis-3'-acetyl-4'-angeloylkhellactone (4), 3'(R)-O-acetyl-4'(S)-O-tigloylkhellactone (5), isorutarine (6), and para-hydroxybenzoic acid (7) exhibited potent inhibitory activities against α-glucosidase, PTP1B, rat lens aldose reductase (RLAR), AChE, BChE, and β-site amyloid precursor protein cleaving enzyme 1 (BACE1). Our results clearly indicate the potential inhibition of α-glucosidase, PTP1B, RLAR, AChE, BChE, and BACE1 by A. decursiva as well as its isolated constituents, which could be further explored to develop therapeutic modalities for the treatment of DM and AD.

  18. Effect of isoquinoline alkaloids from two Hippeastrum species on in vitro acetylcholinesterase activity.

    PubMed

    Pagliosa, L B; Monteiro, S C; Silva, K B; de Andrade, J P; Dutilh, J; Bastida, J; Cammarota, M; Zuanazzi, J A S

    2010-07-01

    The treatment of neurological disorders and neurodegenerative diseases is related to the levels of acetylcholine (ACh) through the inhibition of acetylcholinesterase (AChE). Galanthamine, an important alkaloid isolated from the Amaryllidaceae family, is approved for the pharmacological treatment of Alzheimer's disease (AD) and acts by inhibiting the acetylcholinesterase (AChE) activity. In the present study, Ellman's method was used to verify the inhibition of AChE activity of some isoquinolines alkaloids such as galanthamine, montanine, hippeastrine and pretazettine. At the concentrations 1mM, 500 microm and 100 microm, galanthamine presented an AChE inhibition higher than 90%. Montanine inhibited, in a dose-dependent manner, more than 50% of the enzyme at 1mM concentration. With the concentrations 500 microm and 100 microm, 30-45% of AChE activity inhibition was detected. The alkaloids hippeastrine and pretazettine presented no significant inhibition of the AChE activity. The results demonstrate that montanine significantly inhibits AChE activity at the tested concentrations, suggesting the necessity of further investigations on this alkaloid use in treating neurological disorders.

  19. Crystal structures of Lymnaea stagnalis AChBP in complex with neonicotinoid insecticides imidacloprid and clothianidin

    PubMed Central

    Ihara, Makoto; Okajima, Toshihide; Yamashita, Atsuko; Oda, Takuma; Hirata, Koichi; Nishiwaki, Hisashi; Morimoto, Takako; Akamatsu, Miki; Ashikawa, Yuji; Kuroda, Shun’ichi; Mega, Ryosuke; Kuramitsu, Seiki; Sattelle, David B.

    2008-01-01

    Neonicotinoid insecticides, which act on nicotinic acetylcholine receptors (nAChRs) in a variety of ways, have extremely low mammalian toxicity, yet the molecular basis of such actions is poorly understood. To elucidate the molecular basis for nAChR–neonicotinoid interactions, a surrogate protein, acetylcholine binding protein from Lymnaea stagnalis (Ls-AChBP) was crystallized in complex with neonicotinoid insecticides imidacloprid (IMI) or clothianidin (CTD). The crystal structures suggested that the guanidine moiety of IMI and CTD stacks with Tyr185, while the nitro group of IMI but not of CTD makes a hydrogen bond with Gln55. IMI showed higher binding affinity for Ls-AChBP than that of CTD, consistent with weaker CH–π interactions in the Ls-AChBP–CTD complex than in the Ls-AChBP–IMI complex and the lack of the nitro group-Gln55 hydrogen bond in CTD. Yet, the NH at position 1 of CTD makes a hydrogen bond with the backbone carbonyl of Trp143, offering an explanation for the diverse actions of neonicotinoids on nAChRs. PMID:18338186

  20. Kynurenic acid inhibits glutamatergic transmission to CA1 pyramidal neurons via α7 nAChR-dependent and -independent mechanisms.

    PubMed

    Banerjee, Jyotirmoy; Alkondon, Manickavasagom; Albuquerque, Edson X

    2012-10-15

    Glutamatergic hypofunction and elevated levels of kynurenic acid (KYNA) in the brain are common features of patients with schizophrenia. In vivo studies indicate that in the hippocampus KYNA decreases glutamate levels, presumably via inhibition of α7 nicotinic receptors (nAChRs). Here we tested the hypothesis that basal synaptic glutamate activity in the hippocampus is regulated by tonically active α7 nAChRs and is sensitive to inhibition by KYNA. To this end, spontaneous excitatory postsynaptic currents (EPSCs), sensitive to AMPA receptor antagonist CNQX (10 μM), were recorded from CA1 pyramidal neurons at -70 mV in rat hippocampal slices. The α7 nAChR antagonists α-bungarotoxin (α-BGT, 100 nM) and methyllycaconitine (MLA, 1-50 nM), and the NMDA receptor antagonist 2-amino-5-phosphonovaleric acid (APV, 50 μM) reduced the frequency of EPSCs. MLA and α-BGT had no effect on miniature EPSCs (mEPSCs). The effect of MLA decreased in the presence of APV (50 μM), with 1 nM MLA becoming completely ineffective. KYNA (1-20 μM) suppressed the frequency of EPSCs, without affecting mEPSCs. The effect of KYNA decreased in the presence of MLA (1 nM) or α-BGT (100 nM), with 1 μM KYNA being devoid of any effect. In the presence of both MLA (10 nM) and APV (50 μM) higher KYNA concentrations (5-20 μM) still reduced the frequency of EPSCs. These results suggest that basal synaptic glutamate activity in CA1 pyramidal neurons is maintained in part by tonically active α7 nAChRs and NMDA receptors and is inhibited by micromolar concentrations of KYNA, acting via α7 nAChR-dependent and -independent mechanisms.

  1. Cigarette smoking during pregnancy regulates the expression of specific nicotinic acetylcholine receptor (nAChR) subunits in the human placenta

    SciTech Connect

    Machaalani, R.; Ghazavi, E.; Hinton, T.; Waters, K.A.; Hennessy, A.

    2014-05-01

    Smoking during pregnancy is associated with low birth weight, premature delivery, and neonatal morbidity and mortality. Nicotine, a major pathogenic compound of cigarette smoke, binds to the nicotinic acetylcholine receptors (nAChRs). A total of 16 nAChR subunits have been identified in mammals (9 α, 4 β, and 1 δ, γ and ε subunits). The effect of cigarette smoking on the expression of these subunits in the placenta has not yet been determined, thus constituting the aim of this study. Using RT-qPCR and western blotting, this study investigated all 16 mammalian nAChR subunits in the normal healthy human placenta, and compared mRNA and protein expressions in the placentas from smokers (n = 8) to controls (n = 8). Our data show that all 16 subunit mRNAs are expressed in the normal, non-diseased human placenta and that the expression of α2, α3, α4, α9, β2 and β4 subunits is greater than the other subunits. For mRNA, cigarette smoke exposure was associated with increased expression of the α9 subunit, and decreased expression of the δ subunit. At the protein level, expression of both α9 and δ was increased. Thus, cigarette smoking in pregnancy is sufficient to regulate nAChR subunits in the placenta, specifically α9 and δ subunits, and could contribute to the adverse effects of vasoconstriction and decreased re-epithelialisation (α9), and increased calcification and apoptosis (δ), seen in the placentas of smoking women. - Highlights: • All 16 mammalian nAChR subunits are expressed in the human placenta. • Cigarette smoking increases α9 mRNA and protein in the placenta. • Cigarette smoking decreases δ mRNA but increases δ protein in the placenta.

  2. In vitro acaricidal activity of 1,8-cineole against Sarcoptes scabiei var. cuniculi and regulating effects on enzyme activity.

    PubMed

    Hu, Zhiqiang; Chen, Zhenzhen; Yin, Zhongqiong; Jia, Renyong; Song, Xu; Li, Li; Zou, Yuanfeng; Liang, Xiaoxia; Li, Lixia; He, Changliang; Yin, Lizi; Lv, Cheng; Zhao, Ling; Su, Gang; Ye, Gang; Shi, Fei

    2015-08-01

    1,8-Cineole found in many essential oils is a monoterpene and acts as a repellent against Sarcoptes scabiei var. cuniculi. In the present study, the acaricidal activity of 1,8-cineole against S. scabiei var. cuniculi was evaluated and the acaricidal mechanism was also investigated by assaying enzyme activities. The results showed that the lethal concentration of 50% (LC50) value (95% confidence limit (CL)) and the lethal time of 50% (LT50) value (95% CL) of 1,8-cineole were 2.77 mg/mL and 3.606 h, respectively. The pathological changes under transmission electron microscopy showed that the morphology of the mitochondria was abnormal, the cell nuclear membrane was damaged, and the nuclear chromatin was dissoluted. The activities of superoxide dismutase (SOD), glutathione-s-transferases (GSTs), monoamine oxidase (MAO), nitric oxide synthase (NOS), and acetylcholinesterase (AChE) were significantly changed after treatment with 1,8-cineole for 4, 8, 12, and 24 h. SOD and GSTs are associated with the protection mechanism of scabies mites. And, the activities of SOD and GSTs were increased as compared with the control group. MAO, AChE, and NOS are associated with the nervous system of scabies mites. The activity of MAO was increased whereas the AChE was suppressed. The activity of NOS was suppressed in the high-dose group whereas increased in the middle-dose group and low-dose group. These results indicated that the mechanism of 1,8-cineole mainly attributed to the changes of these enzyme activities related to the nervous system of scabies mites.

  3. Inflammation-induced increase in nicotinic acetylcholine receptor current in cutaneous nociceptive DRG neurons from the adult rat.

    PubMed

    Zhang, X-L; Albers, K M; Gold, M S

    2015-01-22

    The goals of the present study were to determine (1) the properties of the nicotinic acetylcholine receptor (nAChR) currents in rat cutaneous dorsal root ganglion (DRG) neurons; (2) the impact of nAChR activation on the excitability of cutaneous DRG neurons; and (3) the impact of inflammation on the density and distribution of nAChR currents among cutaneous DRG neurons. Whole-cell patch-clamp techniques were used to study retrogradely labeled DRG neurons from naïve and complete Freund's adjuvant inflamed rats. Nicotine-evoked currents were detectable in ∼70% of the cutaneous DRG neurons, where only one of two current types, fast or slow currents based on rates of activation and inactivation, was present in each neuron. The biophysical and pharmacological properties of the fast current were consistent with nAChRs containing an α7 subunit while those of the slow current were consistent with nAChRs containing α3/β4 subunits. The majority of small diameter neurons with fast current were IB4- while the majority of small diameter neurons with slow current were IB4+. Preincubation with nicotine (1 μM) produced a transient (1 min) depolarization and increase in the excitability of neurons with fast current and a decrease in the amplitude of capsaicin-evoked current in neurons with slow current. Inflammation increased the current density of both slow and fast currents in small diameter neurons and increased the percentage of neurons with the fast current. With the relatively selective distribution of nAChR currents in putative nociceptive cutaneous DRG neurons, our results suggest that the role of these receptors in inflammatory hyperalgesia is likely to be complex and dependent on the concentration and timing of acetylcholine release in the periphery.

  4. The recovery of acetylcholinesterase activity and the progression of neuropathological and pathophysiological alterations in the rat basolateral amygdala after soman-induced status epilepticus: relation to anxiety-like behavior

    PubMed Central

    Prager, Eric M.; Aroniadou-Anderjaska, Vassiliki; Almeida-Suhett, Camila P.; Figueiredo, Taiza H.; Apland, James P.; Rossetti, Franco; Olsen, Cara H.; Braga, Maria F.M.

    2014-01-01

    Organophosphorus nerve agents are powerful neurotoxins that irreversibly inhibit acetylcholinesterase (AChE) activity. One of the consequences of AChE inhibition is the generation of seizures and status epilepticus (SE), which cause brain damage, resulting in long-term neurological and behavioral deficits. Increased anxiety is the most common behavioral abnormality after nerve agent exposure. This is not surprising considering that the amygdala, and the basolateral nucleus of the amygdala (BLA) in particular, plays a central role in anxiety, and this structure suffers severe damage by nerve agent-induced seizures. In the present study, we exposed male rats to lethal doses of the nerve agent soman, and determined the time course of recovery of AChE activity, along with the progression of neuropathological and pathophysiological alterations in the BLA, during a 30-day period after exposure. Measurements were taken at 24 hours, 7 days, 14 days, and 30 days after exposure, and at 14 and 30 days, anxiety-like behavior was also evaluated. We found that more than 90% of AChE is inhibited at the onset of SE, and AChE inhibition remains at this level 24 hours later, in the BLA, as well as in the hippocampus, piriform cortex, and prelimbic cortex, which we analyzed for comparison. AChE activity recovered by day 7 in the BLA and day 14 in the other three regions. Significant neuronal loss and neurodegeneration were present in the BLA at 24 hours and throughout the 30-day period. There was no significant loss of GABAergic interneurons in the BLA at 24 hours post-exposure. However, by day 7, the number of GABAergic interneurons in the BLA was reduced, and at 14 and 30 days after soman, the ratio of GABAergic interneurons to the total number of neurons was lower compared to controls. Anxiety-like behavior in the open-field and the acoustic startle response tests was increased at 14 and 30 days post-exposure. Accompanying pathophysiological alterations in the BLA – studied in

  5. Development of a universal approach to increase physical activity among adolescents: the GoActive intervention

    PubMed Central

    Corder, Kirsten; Schiff, Annie; Kesten, Joanna M; van Sluijs, Esther M F

    2015-01-01

    Objectives To develop a physical activity (PA) promotion intervention for adolescents using a process addressing gaps in the literature while considering participant engagement. We describe the initial development stages; (1) existing evidence, (2) large scale opinion gathering and (3) developmental qualitative work, aiming (A) to gain insight into how to increase PA among the whole of year 9 (13–14 years-old) by identifying elements for intervention inclusion (B) to improve participant engagement and (C) to develop and refine programme design. Methods Relevant systematic reviews and longitudinal analyses of change were examined. An intervention was developed iteratively with older adolescents (17.3±0.5 years) and teachers, using the following process: (1) focus groups with (A) adolescents (n=26) and (B) teachers (n=4); (2) individual interviews (n=5) with inactive and shy adolescents focusing on engagement and programme acceptability. Qualitative data were analysed thematically. Results Limitations of the existing literature include lack of evidence on whole population approaches, limited adolescent involvement in intervention development, and poor participant engagement. Qualitative work suggested six themes which may encourage adolescents to do more PA; choice, novelty, mentorship, competition, rewards and flexibility. Teachers discussed time pressures as a barrier to encouraging adolescent PA and suggested between-class competition as a strategy. GoActive aims to increase PA through increased peer support, self-efficacy, group cohesion, self-esteem and friendship quality, and is implemented in tutor groups using a student-led tiered-leadership system. Conclusions We have followed an evidence-based iterative approach to translate existing evidence into an adolescent PA promotion intervention. Qualitative work with adolescents and teachers supported intervention design and addressed lack of engagement with health promotion programmes within this age group

  6. Rosmarinus officinalis L. leaf extract improves memory impairment and affects acetylcholinesterase and butyrylcholinesterase activities in rat brain.

    PubMed

    Ozarowski, Marcin; Mikolajczak, Przemyslaw L; Bogacz, Anna; Gryszczynska, Agnieszka; Kujawska, Malgorzata; Jodynis-Liebert, Jadwiga; Piasecka, Anna; Napieczynska, Hanna; Szulc, Michał; Kujawski, Radoslaw; Bartkowiak-Wieczorek, Joanna; Cichocka, Joanna; Bobkiewicz-Kozlowska, Teresa; Czerny, Boguslaw; Mrozikiewicz, Przemyslaw M

    2013-12-01

    Rosmarinus officinalis L. leaf as part of a diet and medication can be a valuable proposal for the prevention and treatment of dementia. The aim of the study was to assess the effects of subchronic (28-fold) administration of a plant extract (RE) (200 mg/kg, p.o.) on behavioral and cognitive responses of rats linked with acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activity and their mRNA expression level in the hippocampus and frontal cortex. The passive avoidance test results showed that RE improved long-term memory in scopolamine-induced rats. The extract inhibited the AChE activity and showed a stimulatory effect on BuChE in both parts of rat brain. Moreover, RE produced a lower mRNA BuChE expression in the cortex and simultaneously an increase in the hippocampus. The study suggests that RE led to improved long-term memory in rats, which can be partially explained by its inhibition of AChE activity in rat brain.

  7. Playground Designs to Increase Physical Activity Levels during School Recess: A Systematic Review

    ERIC Educational Resources Information Center

    Escalante, Yolanda; García-Hermoso, Antonio; Backx, Karianne; Saavedra, Jose M.

    2014-01-01

    School recess provides a major opportunity to increase children's physical activity levels. Various studies have described strategies to increase levels of physical activity. The purpose of this systematic review is therefore to examine the interventions proposed as forms of increasing children's physical activity levels during recess. A…

  8. Effect of coumaphos on cholinesterase activity, hematology, and biochemical blood parameters of bovines in tropical regions of Mexico.

    PubMed

    Pardío, Violeta T; Ibarra, Nelly De J; Waliszewski, Krzysztof N; López, Karla M

    2007-05-01

    To assess the effect of coumaphos [O-(3-chloro-4-methyl-2-oxo-2H-1-benzopyran-7-yl) O,O-diethyl phosphorothioate] exposure on physiological responses during bovine production, acetylcolinesterase (AChE) and butyrylcholinesterase (BuChE) activities were measured in whole blood, erythrocytes, and plasma of healthy male steers (Bos Taurus x Bos indicus) sprayed with coumaphos at a non-lethal dose of 1 mg kg(- 1) body weight per day once every 14 (in vivo group) or 21 days (southern and central groups). Coumaphos topically administered at 1 mg/kg body weight per day to cattle under normal management practices in tropical areas produced a significant inhibition in erythrocyte (RBC) AChE and BuAChE activities when compared to baseline levels. RBC-AChE activity for the in vivo group decreased 71.3% (P < 0.05) and BuChE activity 59.1% (P < 0.05); RBC-AChE activity decreased 55.1% (P < 0.05) (southern group) and 43.4% (P < 0.05) (central group). Compared to the control specimens, steers from in vivo, southern, and central groups after 150 days of exposure had lower (P < 0.05) leukocyte count, absolute lymphocyte, erythrocyte, and platelet counts. Decreases in RBC-AChE activities correlated with decreased lymphocyte (r = 1.000, p = 0.01), erythrocyte (r = 1.000, p = 0.003), and platelet counts (r = 0.841, p = 0.036). Significantly increased BUN levels (P < 0.05) correlated with the decrease in RBC-AChE activities (r = - 0.997, p = 0.047) and with the decrease in absolute red blood cell (r = - 0.883, p = 0.020) and lymphocyte (r = - 0.825, p = 0.043) counts; increased (P < 0.05) total plasma protein levels correlated with the decrease in RBC-AChE activities (r = -0.998, p = 0.043), absolute red blood cell (r = - 0.998, p = 0.040), lymphocyte (r = - 0.893, p = 0.017), and platelet (r = -0.855, p = 0.030) counts. The physiological responses correlated with the erythrocyte acetylcholinesterase inhibition could be considered as early indicators or warning responses of bovine

  9. The 5-hydroxytryptamine4 receptor agonists prucalopride and PRX-03140 increase acetylcholine and histamine levels in the rat prefrontal cortex and the power of stimulated hippocampal θ oscillations.

    PubMed

    Johnson, David E; Drummond, Elena; Grimwood, Sarah; Sawant-Basak, Aarti; Miller, Emily; Tseng, Elaine; McDowell, Laura L; Vanase-Frawley, Michelle A; Fisher, Katherine E; Rubitski, David M; Stutzman-Engwall, Kim J; Nelson, Robin T; Horner, Weldon E; Gorczyca, Roxanne R; Hajos, Mihaly; Siok, Chester J

    2012-06-01

    5-Hydroxytryptamine (5-HT)(4) receptor agonists reportedly stimulate brain acetylcholine (ACh) release, a property that might provide a new pharmacological approach for treating cognitive deficits associated with Alzheimer's disease. The purpose of this study was to compare the binding affinities, functional activities, and effects on neuropharmacological responses associated with cognition of two highly selective 5-HT(4) receptor agonists, prucalopride and 6,7-dihydro-4-hydroxy-7-isopropyl-6-oxo-N-[3-(piperidin-1-yl)propyl]thieno[2,3-b]pyridine-5-carboxamide (PRX-03140). In vitro, prucalopride and PRX-03140 bound to native rat brain 5-HT(4) receptors with K(i) values of 30 nM and 110 nM, respectively, and increased cAMP production in human embryonic kidney-293 cells expressing recombinant rat 5-HT(4) receptors. In vivo receptor occupancy studies established that prucalopride and PRX-03140 were able to penetrate the brain and bound to 5-HT(4) receptors in rat brain, achieving 50% receptor occupancy at free brain exposures of 330 nM and 130 nM, respectively. Rat microdialysis studies revealed that prucalopride maximally increased ACh and histamine levels in the prefrontal cortex at 5 and 10 mg/kg, whereas PRX-03140 significantly increased cortical histamine levels at 50 mg/kg, failing to affect ACh release at doses lower than 150 mg/kg. In combination studies, donepezil-induced increases in cortical ACh levels were potentiated by prucalopride and PRX-03140. Electrophysiological studies in rats demonstrated that both compounds increased the power of brainstem-stimulated hippocampal θ oscillations at 5.6 mg/kg. These findings show for the first time that the 5-HT(4) receptor agonists prucalopride and PRX-03140 can increase cortical ACh and histamine levels, augment donepezil-induced ACh increases, and increase stimulated-hippocampal θ power, all neuropharmacological parameters consistent with potential positive effects on cognitive processes.

  10. Auxofuran, a novel metabolite that stimulates the growth of fly agaric, is produced by the mycorrhiza helper bacterium Streptomyces strain AcH 505.

    PubMed

    Riedlinger, Julia; Schrey, Silvia D; Tarkka, Mika T; Hampp, Rüdiger; Kapur, Manmohan; Fiedler, Hans-Peter

    2006-05-01

    The mycorrhiza helper bacterium Streptomyces strain AcH 505 improves mycelial growth of ectomycorrhizal fungi and formation of ectomycorrhizas between Amanita muscaria and spruce but suppresses the growth of plant-pathogenic fungi, suggesting that it produces both fungal growth-stimulating and -suppressing compounds. The dominant fungal-growth-promoting substance produced by strain AcH 505, auxofuran, was isolated, and its effect on the levels of gene expression of A. muscaria was investigated. Auxofuran and its synthetic analogue 7-dehydroxy-auxofuran were most effective at a concentration of 15 microM, and application of these compounds led to increased lipid metabolism-related gene expression. Cocultivation of strain AcH 505 and A. muscaria stimulated auxofuran production by the streptomycete. The antifungal substances produced by strain AcH 505 were identified as the antibiotics WS-5995 B and C. WS-5995 B completely blocked mycelial growth at a concentration of 60 microM and caused a cell stress-related gene expression response in A. muscaria. Characterization of these compounds provides the foundation for molecular analysis of the fungus-bacterium interaction in the ectomycorrhizal symbiosis between fly agaric and spruce.

  11. Acetylcholinesterase Inhibitors (AChEI's) for the treatment of visual hallucinations in schizophrenia: a case report

    PubMed Central

    2010-01-01

    Background Visual hallucinations are commonly seen in various neurological and psychiatric disorders including schizophrenia. Current models of visual processing and studies in diseases including Parkinsons Disease and Lewy Body Dementia propose that Acetylcholine (Ach) plays a pivotal role in our ability to accurately interpret visual stimuli. Depletion of Ach is thought to be associated with visual hallucination generation. AchEI's have been used in the targeted treatment of visual hallucinations in dementia and Parkinson's Disease patients. In Schizophrenia, it is thought that a similar Ach depletion leads to visual hallucinations and may provide a target for drug treatment Case Presentation We present a case of a patient with Schizophrenia presenting with treatment resistant and significantly distressing visual hallucinations. After optimising treatment for schizophrenia we used Rivastigmine, an AchEI, as an adjunct to treat her symptoms successfully. Conclusions This case is the first to illustrate this novel use of an AchEI in the targeted treatment of visual hallucinations in a patient with Schizophrenia. Targeted therapy of this kind can be considered in challenging cases although more evidence is required in this field. PMID:20822516

  12. Glial cell line-derived neurotrophic factor (GDNF) protein content in rat skeletal muscle is altered by increased physical activity in vivo and in vitro

    PubMed Central

    McCullough, Monica J.; Peplinski, Nathan G.; Kinnell, Kyle R.; Spitsbergen, John M.

    2010-01-01

    Current evidence suggests that exercise and glial cell line-derived neurotrophic factor (GDNF) independently cause significant morphological changes in the neuromuscular system. The aim of the current study was to determine if increased physical activity regulates GDNF protein content in rat skeletal muscle. Extensor Digitorum Longus (EDL) and Soleus (SOL) hindlimb skeletal muscles were analyzed following 2 weeks of involuntary exercise and 4 hours of field stimulation or stretch in muscle bath preparations. GDNF protein content was measured via ELISA. Two weeks of exercise increased GDNF protein content in SOL as compared to sedentary controls (4.4 ±0.3 pg GDNF/mg tissue and 3.1 ±0.6 pg GDNF/mg tissue, respectively) and decreased GDNF protein content in EDL as compared to controls (1.0 ±0.1 pg GDNF/mg tissue and 2.3 ±0.7 pg GDNF/mg tissue, respectively). GDNF protein content in the EDL decreased following both field stimulation (56% ±18% decrease from controls) and stretch (66% ±10% decrease from controls). SOL responded to field stimulation with a 38% ±7% increase from controls in GDNF protein content, but showed no change following stretch. Pre-treatment with α-bungarotoxin abolished the effects of field stimulation in both muscles and blocked the effect of stretch in EDL. α-bungarotoxin pre-treatment and stretch increased GDNF protein content to 240% ±10% of controls in the SOL. Exposure to carbamylcholine decreased GDNF protein content to 51% ±28% of controls in the EDL but not SOL. These results suggest that GDNF protein content in skeletal muscle may be controlled by stretch, where it may increase GDNF protein content, and membrane depolarization/ACh which acts to decrease GDNF protein content. PMID:21081155

  13. From crystal structure of α-conotoxin GIC in complex with Ac-AChBP to molecular determinants of its high selectivity for α3β2 nAChR

    PubMed Central

    Lin, Bo; Xu, Manyu; Zhu, Xiaopeng; Wu, Yong; Liu, Xi; Zhangsun, Dongting; Hu, Yuanyan; Xiang, Shi-Hua; Kasheverov, Igor E.; Tsetlin, Victor I.; Wang, Xinquan; Luo, Sulan

    2016-01-01

    Acetylcholine binding proteins (AChBPs) are unique spatial homologs of the ligand-binding domains of nicotinic acetylcholine receptors (nAChRs), and they reproduce some pharmacological properties of nAChRs. X-ray crystal structures of AСhBP in complex with α-conotoxins provide important insights into the interactions of α-conotoxins with distinct nAChR subtypes. Although considerable efforts have been made to understand why α-conotoxin GIC is strongly selective for α3β2 nAChR, this question has not yet been solved. Here we present the structure of α-conotoxin GIC in complex with Aplysia californica AChBP (Ac-AChBP) at a resolution of 2.1 Å. Based on this co-crystal structure complemented with molecular docking data, we suggest the key residues of GIC in determining its high affinity and selectivity for human α3β2 vs α3β4 nAChRs. These suggestions were checked by radioligand and electrophysiology experiments, which confirmed the functional role of detected contacts for GIC interactions with Ac-AChBP and α3β2 nAChR subtypes. While GIC elements responsible for its high affinity binding with Ac-AChBP and α3β2 nAChR were identified, our study also showed the limitations of computer modelling in extending the data from the X-ray structures of the AChBP complexes to all nAChR subtypes. PMID:26925840

  14. Increased hepcidin in transferrin-treated thalassemic mice correlates with increased liver BMP2 expression and decreased hepatocyte ERK activation.

    PubMed

    Chen, Huiyong; Choesang, Tenzin; Li, Huihui; Sun, Shuming; Pham, Petra; Bao, Weili; Feola, Maria; Westerman, Mark; Li, Guiyuan; Follenzi, Antonia; Blanc, Lionel; Rivella, Stefano; Fleming, Robert E; Ginzburg, Yelena Z

    2016-03-01

    Iron overload results in significant morbidity and mortality in β-thalassemic patients. Insufficient hepcidin is implicated in parenchymal iron overload in β-thalassemia and approaches to increase hepcidin have therapeutic potential. We have previously shown that exogenous apo-transferrin markedly ameliorates ineffective erythropoiesis and increases hepcidin expression in Hbb(th1/th1) (thalassemic) mice. We utilize in vivo and in vitro systems to investigate effects of exogenous apo-transferrin on Smad and ERK1/2 signaling, pathways that participate in hepcidin regulation. Our results demonstrate that apo-transferrin increases hepcidin expression in vivo despite decreased circulating and parenchymal iron concentrations and unchanged liver Bmp6 mRNA expression in thalassemic mice. Hepatocytes from apo-transferrin-treated mice demonstrate decreased ERK1/2 pathway and increased serum BMP2 concentration and hepatocyte BMP2 expression. Furthermore, hepatocyte ERK1/2 phosphorylation is enhanced by neutralizing anti-BMP2/4 antibodies and suppressed in vitro in a dose-dependent manner by BMP2, resulting in converse effects on hepcidin expression, and hepatocytes treated with MEK/ERK1/2 inhibitor U0126 in combination with BMP2 exhibit an additive increase in hepcidin expression. Lastly, bone marrow erythroferrone expression is normalized in apo-transferrin treated thalassemic mice but increased in apo-transferrin injected wild-type mice. These findings suggest that increased hepcidin expression after exogenous apo-transferrin is in part independent of erythroferrone and support a model in which apo-transferrin treatment in thalassemic mice increases BMP2 expression in the liver and other organs, decreases hepatocellular ERK1/2 activation, and increases nuclear Smad to increase hepcidin expression in hepatocytes.

  15. Gastrointestinal acetylcholinesterase activity following endotracheal microinstillation inhalation exposure to sarin in guinea pigs.

    PubMed

    Chanda, Soma; Song, Jian; Rezk, Peter; Sabnekar, Praveena; Doctor, Bhupendra P; Sciuto, Alfred M; Nambiar, Madhusoodana P

    2010-09-06

    The goal of this study was to assess acetylcholinesterase (AChE) inhibition at different regions of the gastrointestinal (GI) tract following inhalation exposure to nerve agent sarin. Seven major regions of the GI tract were removed from saline control animals (n=3) and 677.4 mg/m(3) sarin-exposed animals at 4h (n=4) and 24h (n=4) post-exposure. AChE activity was determined in blood and homogenized tissue supernatant by specific Ellman's assay using Iso-OMPA, a BChE inhibitor, and expressed as activity/optical density of hemoglobin for blood and activity/mg protein for tissues. Our data showed that the AChE activity was significantly decreased for groups both 4h and 24h post-sarin exposure. Among the seven chosen regions of the guinea pig GI tract, duodenum showed the highest AChE activity in control animals. The AChE activity was significantly decreased in the stomach (p=0.03), duodenum (p=0.029), jejunum (p=0.006), and ileum (p=0.006) 4h following sarin exposure. At 24h post-sarin exposure the AChE activity of duodenum (p=0.029) and ileum (p=0.006) was significantly inhibited. Esophagus showed no inhibition following sarin exposure at both 4h and 24h groups. These results suggest that the AChE activity is different in different regions of the GI tract and highest levels of AChE inhibition following sarin exposure were seen in regions exhibiting higher overall AChE activity and cholinergic function.

  16. Intrathymic Tfh/B Cells Interaction Leads to Ectopic GCs Formation and Anti-AChR Antibody Production: Central Role in Triggering MG Occurrence.

    PubMed

    Zhang, Xiaoyan; Liu, Shasha; Chang, Ting; Xu, Jiang; Zhang, Chunmei; Tian, Feng; Sun, Yuanjie; Song, Chaojun; Yi, Wei; Lin, Hong; Li, Zhuyi; Yang, Kun

    2016-01-01

    Myasthenia gravis is a typical acetylcholine receptor (AChR) antibody-mediated autoimmune disease in which thymus frequently presents follicular hyperplasia or thymoma. It is now widely accepted that the thymus is probably the site of AChR autosensitization and autoantibody production. However, the exact mechanism that triggers intrathymic AChR antibody production is still unknown. T follicular helper cells, recently identified responsible for B cell maturation and antibody production in the secondary lymphoid organs, were involved in many autoimmune diseases. Newly studies found T follicular helper (Tfh) cells increased in the peripheral blood of myasthenia gravis (MG). Whether it appears in the thymus of MG and its role in the intrathymic B cells help and autoantibody production is unclear. Therefore, this study aims to determine in more detail whether Tfh/B cell interaction exist in MG thymus and to address its role in the ectopic germinal centers (GCs) formation and AChR antibody production. We observed the frequency of Tfh cells and its associated transcription factor Bcl-6, key cytokine IL-21 enhanced both in the thymocytes and peripheral blood mononuclear cells (PBMCs) of MG patients. In parallel, we also showed increased B cells and autoantibody titers in MG peripheral blood and thymus. Confocal microscope results demonstrated Tfh and B cells co-localized within the ectopic GCs in MG thymus, suggesting putative existence of Tfh/B cells interaction. In vitro studies further showed dynamic behavior of Tfh/B cells interaction and Tfh cells induced autoantibody secretion might through its effector cytokine IL-21. Altogether, our data demonstrated that intrathymic Tfh/B cells interaction played a key role in thymic ectopic GCs formation and anti-AChR antibody production, which might trigger MG occurrence.

  17. In vitro reactivation of sarin-inhibited human acetylcholinesterase (AChE) by bis-pyridinium oximes connected by xylene linkers.

    PubMed

    Acharya, Jyotiranjan; Dubey, Devendra Kumar; Srivastava, Ashish Kumar; Raza, Syed Kalbey

    2011-02-01

    A series of bis-pyridinium oximes connected by xylene linkers were synthesized and their in vitro reactivation potential was evaluated against human acetylcholinesterase (hAChE) inhibited by nerve agent sarin and the data were compared with 2-PAM and obidoxime. Among the synthesized compounds, N,N'-p-xylene-bis-[(2,2'-hydroxyiminomethyl)pyridinium] dibromide (3c) was found to be the most potent reactivator for hAChE inhibited by sarin. The oxime 3c exhibited 45% regeneration of inhibited hAChE, in comparison to 34% and 24% regeneration by 2-PAM and obidoxime, respectively, at a concentration of 10(-3) M within 10 min. The higher reactivation efficacies of these oximes were attributed to their acid dissociation constants (pKa). The pKa values of all the oximes were determined spectrophotometrically and correlated with their observed reactivation potential. This method involving the in vitro reactivation of inhibited hAChE may be useful for the screening of new oximes as reactivators.

  18. Geological Mapping of the Ac-H-10 Rongo and Ac-H-15 Zadeni quadrangles of Ceres from NASA's Dawn Mission.

    NASA Astrophysics Data System (ADS)

    Platz, Thomas; Nathues, Andreas; Sizemore, Hanna; Ruesch, Ottaviano; Hoffmann, Martin; Schaefer, Michael; Crown, David; Mest, Scott; Aileen Yingst, R.; Williams, David; Buczkowski, Debra; Hughson, Kynan; Kneissl, Thomas; Schmedemann, Nico; Schorghofer, Norbert; Nass, Andrea; Preusker, Frank; Russell, Christopher

    2016-04-01

    On March 6, 2015 NASA's Dawn spacecraft arrived at (1) Ceres, the largest object in the main asteroid belt. Dawn is studying the dwarf planet more than one year through successively lower orbits at increasing resolution. Main orbital phases include Survey Orbit, High Altitude Mapping Orbit (HAMO), and Low Altitude Mapping Orbit (LAMO) where Framing Camera (FC) [1] resolution increased from c.400 m/px to c.140 m/px and c.35 m/px, respectively. The Dawn Science Team is conducting geological mapping campaigns for Ceres (as done before for Vesta [2,3]) and includes the production of a Survey/HAMO-based global geological map and a series of 15 LAMO-based geological quadrangle maps. This abstract presents HAMO-based geological maps of Ac-H-10 Rongo (22°N-22°S, 288-360°E) and Ac-H-15 Zadeni (65°-90°S, 0°-360°E) quadrangles. The Rongo Quadrangle is located at the equatorial region and comprises the unique isolated mountain Ahuna Mons (10.5°S/316.0°E; formerly known as the pyramid), abundant impact craters spanning a range in diameters and states of preservation - from fresh to highly degraded - , and a number of tholi, which may represent surface expressions of sub-surface diapir intrusions. The SW portion of the quandrangle is characterised by Yalode (D=260 km) sourced ejecta. The Zadeni Quadrangle is dominated by the 122-km-diameter crater Zadeni located at 70.2°S/37.4°E) and a suite of mid-sized craters whose morphologies range from fresh to highly degraded. Portions of the quadrangle are covered by Urvara [4] and Yalode [5] ejecta materials. The South Polar Region is poorly illuminated and the South Pole itself is likely located within a larger impact structure. Future work of this mapping campaign includes revision of HAMO-based line work (e.g., contacts) with higher resolution LAMO data. Final interpretations regarding the geological histories of these two quadrangles will also be based on FC colour and stereo-derived topography data, VIR spectra as well

  19. Unmasking tandem site interaction in human acetylcholinesterase. Substrate activation with a cationic acetanilide substrate.

    PubMed

    Johnson, Joseph L; Cusack, Bernadette; Davies, Matthew P; Fauq, Abdul; Rosenberry, Terrone L

    2003-05-13

    Acetylcholinesterase (AChE) contains a narrow and deep active site gorge with two sites of ligand binding, an acylation site (or A-site) at the base of the gorge, and a peripheral site (or P-site) near the gorge entrance. The P-site contributes to catalytic efficiency by transiently binding substrates on their way to the acylation site, where a short-lived acyl enzyme intermediate is produced. A conformational interaction between the A- and P-sites has recently been found to modulate ligand affinities. We now demonstrate that this interaction is of functional importance by showing that the acetylation rate constant of a substrate bound to the A-site is increased by a factor a when a second molecule of substrate binds to the P-site. This demonstration became feasible through the introduction of a new acetanilide substrate analogue of acetylcholine, 3-(acetamido)-N,N,N-trimethylanilinium (ATMA), for which a = 4. This substrate has a low acetylation rate constant and equilibrates with the catalytic site, allowing a tractable algebraic solution to the rate equation for substrate hydrolysis. ATMA affinities for the A- and P-sites deduced from the kinetic analysis were confirmed by fluorescence titration with thioflavin T as a reporter ligand. Values of a >1 give rise to a hydrolysis profile called substrate activation, and the AChE site-specific mutant W86F, and to a lesser extent wild-type human AChE itself, showed substrate activation with acetylthiocholine as the substrate. Substrate activation was incorporated into a previous catalytic scheme for AChE in which a bound P-site ligand can also block product dissociation from the A-site, and two additional features of the AChE catalytic pathway were revealed. First, the ability of a bound P-site ligand to increase the substrate acetylation rate constant varied with the structure of the ligand: thioflavin T accelerated ATMA acetylation by a factor a(2) of 1.3, while propidium failed to accelerate. Second, catalytic rate

  20. Intracerebroventricular D-galactose administration impairs memory and alters activity and expression of acetylcholinesterase in the rat.

    PubMed

    Rodrigues, André Felipe; Biasibetti, Helena; Zanotto, Bruna Stela; Sanches, Eduardo Farias; Pierozan, Paula; Schmitz, Felipe; Parisi, Mariana Migliorini; Barbé-Tuana, Florencia; Netto, Carlos Alexandre; Wyse, Angela T S

    2016-05-01

    Tissue accumulation of galactose is a hallmark in classical galactosemia. Cognitive deficit is a symptom of this disease which is poorly understood. The aim of this study was to investigate the effects of intracerebroventricular administration of galactose on memory (inhibitory avoidance and novel object recognition tasks) of adult rats. We also investigated the effects of galactose on acetylcholinesterase (AChE) activity, immunocontent and gene expression in hippocampus and cerebral cortex. Wistar rats received a single injection of galactose (4mM) or saline (control). For behavioral parameters, galactose was injected 1h or 24h previously to the testing. For biochemical assessment, animals were decapitated 1h, 3h or 24h after galactose or saline injection; hippocampus and cerebral cortex were dissected. Results showed that galactose impairs the memory formation process in aversive memory (inhibitory avoidance task) and recognition memory (novel object recognition task) in rats. The activity of AChE was increased, whereas the gene expression of this enzyme was decreased in hippocampus, but not in cerebral cortex. These findings suggest that these changes in AChE may, at least in part, to lead to memory impairment caused by galactose. Taken together, our results can help understand the etiopathology of classical galactosemia.

  1. [Effect of acetylcholine and acetylcholinesterase on the activity of contractile vacuole of Amoeba proteus].

    PubMed

    Bagrov, Ia Iu; Manusova, N B

    2011-01-01

    Acetylcholine (ACh, 1 microM) stimulates activity of the contractile vacuole of proteus. The effect of ACh is not mimicked by its analogs which are not hydrolyzed by acetylcholinesterase (AChE), i. e., carbacholine and 5-methylfurmethide. The effect of ACh is not sensitive to the blocking action of M-cholinolytics, atropine and mytolone, but is suppressed by N-cholinolytic, tubocurarine. The inhibitors of AChE, eserine (0.01 microM) and armine (0.1 microM), suppress the effect of ACh on amoeba contractile vacuole. ACh does not affect activation of contractile vacuole induced by arginine-vasopressin (1 microM), but it blocks such effect of opiate receptors agonist, dynorphin A1-13 (0.01 microM). This effect of ACh is also suppressed by the inhibitors of AChE. These results suggest that, in the above-described effects of ACh, AChE acts not as an antagonist, but rather as a synergist.

  2. Blockade of Neuronal α7-nAChR by α-Conotoxin ImI Explained by Computational Scanning and Energy Calculations

    PubMed Central

    Yu, Rilei; Craik, David J.; Kaas, Quentin

    2011-01-01

    α-Conotoxins potently inhibit isoforms of nicotinic acetylcholine receptors (nAChRs), which are essential for neuronal and neuromuscular transmission. They are also used as neurochemical tools to study nAChR physiology and are being evaluated as drug leads to treat various neuronal disorders. A number of experimental studies have been performed to investigate the structure-activity relationships of conotoxin/nAChR complexes. However, the structural determinants of their binding interactions are still ambiguous in the absence of experimental structures of conotoxin-receptor complexes. In this study, the binding modes of α-conotoxin ImI to the α7-nAChR, currently the best-studied system experimentally, were investigated using comparative modeling and molecular dynamics simulations. The structures of more than 30 single point mutants of either the conotoxin or the receptor were modeled and analyzed. The models were used to explain qualitatively the change of affinities measured experimentally, including some nAChR positions located outside the binding site. Mutational energies were calculated using different methods that combine a conformational refinement procedure (minimization with a distance dependent dielectric constant or explicit water, or molecular dynamics using five restraint strategies) and a binding energy function (MM-GB/SA or MM-PB/SA). The protocol using explicit water energy minimization and MM-GB/SA gave the best correlations with experimental binding affinities, with an R2 value of 0.74. The van der Waals and non-polar desolvation components were found to be the main driving force for binding of the conotoxin to the nAChR. The electrostatic component was responsible for the selectivity of the various ImI mutants. Overall, this study provides novel insights into the binding mechanism of α-conotoxins to nAChRs and the methodological developments reported here open avenues for computational scanning studies of a rapidly expanding range of wild

  3. {alpha}7-nAChR-mediated suppression of hyperexcitability of colonic dorsal root ganglia neurons in experimental colitis.

    PubMed

    Abdrakhmanova, Galya R; AlSharari, Shakir; Kang, Minho; Damaj, M Imad; Akbarali, Hamid I

    2010-09-01

    Controlled clinical trials of nicotine transdermal patch for treatment of ulcerative colitis have been shown to improve histological and global clinical scores of colitis. Here we report that nicotine (1 microM) suppresses in vitro hyperexcitability of colonic dorsal root ganglia (DRG) (L(1)-L(2)) neurons in the dextran sodium sulfate (DSS)-induced mouse model of acute colonic inflammation. Nicotine gradually reduced regenerative multiple-spike action potentials in colitis mice to a single action potential. Nicotine's effect on hyperexcitability of inflamed neurons was blocked in the presence of an alpha(7)-nicotinic acetylcholine receptor (nAChR) antagonist, methyllicaconitine, while choline, the alpha(7)-nAChR agonist, induced a similar effect to that of nicotine. Consistent with these findings, nicotine failed to suppress hyperexcitability in colonic DRG neurons from DSS-treated alpha(7) knockout mice. Furthermore, colonic DRG neurons from DSS-treated alpha(7) knockout mice were characterized by lower rheobase (10 +/- 5 vs. 77 +/- 13 pA, respectively) and current threshold (28 +/- 4 vs. 103 +/- 8 pA, respectively) levels than DSS-treated C57BL/J6 mice. An interesting observation of this study is that 8 of 12 colonic DRG (L(1)-L(2)) neurons from control alpha(7) knockout mice exhibited multiple-spike action potential firing while no wild-type neurons did. Overall, our findings suggest that nicotine at low 1 microM concentration suppresses in vitro hyperexcitability of inflamed colonic DRG neurons in a mouse model of acute colonic inflammation via activation of alpha(7)-nAChRs.

  4. The effect of increasing autonomy through choice on young children’s physical activity behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing autonomy by manipulating the choice of available physical activity options in a laboratory setting can increase physical activity in older children and adults. However, the effect of manipulating the number of physically active choices has yet to be examined in young children in a gymnas...

  5. Promising School-Based Strategies and Intervention Guidelines to Increase Physical Activity of Adolescents

    ERIC Educational Resources Information Center

    Pardo, Berta Murillo; Bengoechea, Enrique Garcia; Lanaspa, Eduardo Generelo; Bush, Paula L.; Casterad, Javier Zaragoza; Clemente, Jose A. Julian; Gonzalez, Luis Garcia

    2013-01-01

    This narrative review describes the available scientific evidence regarding promising school-based strategies to increase physical activity of adolescents. We conducted a literature search for studies published up to 2011, regarding adolescent physical activity intervention studies that resulted in increased physical activity (regardless of…

  6. AT–1001: a high-affinity α3β4 nAChR ligand with novel nicotine-suppressive pharmacology

    PubMed Central

    Cippitelli, Andrea; Wu, Jinhua; Gaiolini, Kelly A; Mercatelli, Daniela; Schoch, Jennifer; Gorman, Michelle; Ramirez, Alejandra; Ciccocioppo, Roberto; Khroyan, Taline V; Yasuda, Dennis; Zaveri, Nurulain T; Pascual, Conrado; Xie, Xinmin (Simon); Toll, Lawrence

    2015-01-01

    Background and Purpose The α3β4 subtype of nicotinic acetylcholine receptors (nAChRs) has been implicated in mediating nicotine reinforcement processes. AT-1001 has been recently described as a high-affinity and selective α3β4 nAChR antagonist that blocks nicotine self-administration in rats. The aim of this study was to investigate the mechanism of action underlying the nicotine-suppressive effects of AT-1001. Experimental Approach Effects of AT-1001 were determined using in vitro assays and rat models of nicotine addiction, and compared with varenicline. Key Results AT-1001 and its analogue AT-1012 were functionally selective as antagonists for α3β4 over α4β2 nAChRs, but not to the same extent as the binding selectivity, and had partial agonist activity at α3β4 nAChRs. In contrast, varenicline was a partial agonist at α4β2, a weak agonist at α3β4 and inhibited α4β2 at a much lower concentration than it inhibited α3β4 nAChRs. AT-1001 and varenicline also had very different in vivo properties. Firstly, AT-1001 did not exhibit reinforcing properties per se while varenicline was self-administered. Secondly, systemic treatment with AT-1001 did not induce reinstatement of nicotine seeking but rather attenuated reinstatement induced by varenicline, as well as nicotine. Finally, unlike varenicline, AT-1001 selectively blocked nicotine self-administration without altering alcohol lever pressing as assessed in an operant co-administration paradigm. Conclusions and Implications These findings describe a more complex AT-1001 in vitro profile than previously appreciated and provide further support for the potential of AT-1001 and congeners as clinically useful compounds for smoking cessation, with a mechanism of action distinct from currently available medications. PMID:25440006

  7. An Evaluation of Photographic Activity Schedules to Increase Independent Playground Skills in Young Children with Autism

    ERIC Educational Resources Information Center

    Akers, Jessica S.; Higbee, Thomas S.; Pollard, Joy S.; Pellegrino, Azure J.; Gerencser, Kristina R.

    2016-01-01

    We used photographic activity schedules to increase the number of play activities completed by children with autism during unstructured time on the playground. All 3 participants engaged in more playground activities during and after training, and they continued to complete activities when novel photographs were introduced.

  8. Centrally injected histamine increases posterior hypothalamic acetylcholine release in hemorrhage-hypotensive rats.

    PubMed

    Altinbas, Burcin; Yilmaz, Mustafa S; Savci, Vahide; Jochem, Jerzy; Yalcin, Murat

    2015-01-01

    Histamine, acting centrally as a neurotransmitter, evokes a reversal of hemorrhagic hypotension in rats due to the activation of the sympathetic and the renin-angiotensin systems as well as the release of arginine vasopressin and proopiomelanocortin-derived peptides. We demonstrated previously that central nicotinic cholinergic receptors are involved in the pressor effect of histamine. The aim of the present study was to examine influences of centrally administrated histamine on acetylcholine (ACh) release at the posterior hypothalamus-a region characterized by location of histaminergic and cholinergic neurons involved in the regulation of the sympathetic activity in the cardiovascular system-in hemorrhage-hypotensive anesthetized rats. Hemodynamic and microdialysis studies were carried out in Sprague-Dawley rats. Hemorrhagic hypotension was induced by withdrawal of a volume of 1.5 ml blood/100 g body weight over a period of 10 min. Acute hemorrhage led to a severe and long-lasting decrease in mean arterial pressure (MAP), heart rate (HR), and an increase in extracellular posterior hypothalamic ACh and choline (Ch) levels by 56% and 59%, respectively. Intracerebroventricularly (i.c.v.) administered histamine (50, 100, and 200 nmol) dose- and time-dependently increased MAP and HR and caused an additional rise in extracellular posterior hypothalamic ACh and Ch levels at the most by 102%, as compared to the control saline-treated group. Histamine H1 receptor antagonist chlorpheniramine (50 nmol; i.c.v.) completely blocked histamine-evoked hemodynamic and extracellular posterior hypothalamic ACh and Ch changes, whereas H2 and H3/H4 receptor blockers ranitidine (50 nmol; i.c.v.) and thioperamide (50 nmol; i.c.v.) had no effect. In conclusion, centrally administered histamine, acting via H1 receptors, increases ACh release at the posterior hypothalamus and causes a pressor and tachycardic response in hemorrhage-hypotensive anesthetized rats.

  9. [Two cases of Lambert-Eaton syndrome with an increase of serum cholinesterase activity].

    PubMed

    Ciechanowski, K; Cebula, D

    1997-02-01

    Paraneoplastic Lambert-Eaton myasthenia syndrome is presented in two cases with small cell lung cancer. An increase of serum cholinesterase activity was explained by induced release of biologically active proteins by neoplastic tissue.

  10. The impact of a parkinsonian lesion on dynamic striatal dopamine transmission depends on nicotinic receptor activation.

    PubMed

    Jennings, Katie A; Platt, Nicola J; Cragg, Stephanie J

    2015-10-01

    Dopamine function is disturbed in Parkinson's disease (PD), but whether and how release of dopamine from surviving neurons is altered has long been debated. Nicotinic acetylcholine receptors (nAChRs) on dopamine axons powerfully govern dopamine release and could be critical contributing factors. We revisited whether fundamental properties of dopamine transmission are changed in a parkinsonian brain and tested the potentially profound masking effects of nAChRs. Using real-time detection of dopamine in mouse striatum after a partial 6-hydroxydopamine lesion and under nAChR inhibition, we reveal that dopamine signals show diminished sensitivity to presynaptic activity. This effect manifested as diminished contrast between DA release evoked by the lowest versus highest frequencies. This reduced activity-dependence was underpinned by loss of short-term facilitation of dopamine release, consistent with an increase in release probability (Pr). With nAChRs active, the reduced activity-dependence of dopamine release after a parkinsonian lesion was masked. Consequently, moment-by-moment variation in activity of nAChRs may lead to dynamic co-variation in dopamine signal impairments in PD.

  11. Immigrant background and medicine use for aches: national representative study of adolescents

    PubMed Central

    2014-01-01

    Objectives The aims of the study were to examine the association between immigrant background and medicine use for headache and stomach-ache among adolescents, and whether symptoms of headache and stomach-ache could explain the differences in medicine use. Methods We used data from the Danish contribution to the WHO-affiliated international cross-sectional survey Health Behaviour in School-aged Children (HBSC) in 2006. Among boys, a total of 4170 ethnic Danes, 244 descendants of immigrants, and 224 immigrants participated. Among girls, 4310 ethnic Danes, 264 descendants of immigrants, and 232 immigrants were included. The associations between migrant background and medicine use for headache and stomach-ache by means of multilevel multivariate logistic regression analyses adjusted for age group, symptoms and the clustering effect of school and stratified by sex due to interactions. Results Among boys, the risk of medicine use for stomach-ache was higher for immigrants (odds ratio (OR), 1.54; 95% confidence intervals (CI), 0.99-2.44)) and descendants (OR, 1.97 (1.33-2.94)) compared to ethnic Danes. Similar associations were found for use of medicine for stomach-ache for immigrant girls (OR, 1.55 (1.12-2.15) and use of medicine for headache among boys (immigrants (OR, 1.36 (1.02-1.97 and descendants (1.48 (1.12-1.97)). Symptoms of aches were all independently associated with medicine use. After adjusting for these factors the association between immigrant background and medicine use attenuated slightly. Conclusion Among adolescents in Denmark, the risk of medicine use for headache and stomach-ache was higher for immigrants and descendants as compared to ethnic Danes, with the exception of medicine use for headache among girls. PMID:25848541

  12. Optogenetic Release of ACh Induces Rhythmic Bursts of Perisomatic IPSCs in Hippocampus

    PubMed Central

    Karson, Miranda A.; Klugmann, Matthias; Alger, Bradley E.

    2011-01-01

    Acetylcholine (ACh) influences a vast array of phenomena in cortical systems. It alters many ionic conductances and neuronal firing behavior, often by regulating membrane potential oscillations in populations of cells. Synaptic inhibition has crucial roles in many forms of oscillation, and cholinergic mechanisms regulate both oscillations and synaptic inhibition. In vitro investigations using bath-application of cholinergic receptor agonists, or bulk tissue electrical stimulation to release endogenous ACh, have led to insights into cholinergic function, but questions remain because of the relative lack of selectivity of these forms of stimulation. To investigate the effects of selective release of ACh on interneurons and oscillations, we used an optogenetic approach in which the light-sensitive non-selective cation channel, Channelrhodopsin2 (ChR2), was virally delivered to cholinergic projection neurons in the medial septum/diagonal band of Broca (MS/DBB) of adult mice expressing Cre-recombinase under the control of the choline-acetyltransferase (ChAT) promoter. Acute hippocampal slices obtained from these animals weeks later revealed ChR2 expression in cholinergic axons. Brief trains of blue light pulses delivered to untreated slices initiated bursts of ACh-evoked, inhibitory post-synaptic currents (L-IPSCs) in CA1 pyramidal cells that lasted for 10's of seconds after the light stimulation ceased. L-IPSC occurred more reliably in slices treated with eserine and a very low concentration of 4-AP, which were therefore used in most experiments. The rhythmic, L-IPSCs were driven primarily by muscarinic ACh receptors (mAChRs), and could be suppressed by endocannabinoid release from pyramidal cells. Finally, low-frequency oscillations (LFOs) of local field potentials (LFPs) were significantly cross-correlated with the L-IPSCs, and reversal of the LFPs near s. pyramidale confirmed that the LFPs were driven by perisomatic inhibition. This optogenetic approach may be a

  13. Vitamin E supplementation increases the resistance of both LDL and HDL to oxidation and increases cholesteryl ester transfer activity.

    PubMed

    Arrol, S; Mackness, M I; Durrington, P N

    2000-05-01

    There is increasing evidence that lipid peroxidation and oxidative modification of low density lipoprotein (LDL) is important in atherogenesis. Evidence that antioxidant therapy decreases mortality is, however, inconclusive. We have examined the effects of vitamin E on the susceptibility of LDL and high density lipoprotein (HDL) to oxidation, and on cholesteryl ester heteroexchange in an in vitro system using autologous serum lipoproteins. Vitamin E in doses of 200 and 400 mg/day were administered orally to 21 healthy volunteers (12 females and nine males) aged between 23 and 50 years, and to 16 healthy volunteers (eight females and eight males) aged between 22 and 51 years for 50 days, respectively. Fasting serum lipoproteins, susceptibility of lipoproteins to oxidation and cholesteryl ester transfer activity (CETA) were measured before and after vitamin E supplementation. Serum lipoprotein and lipid concentrations did not change significantly in either group. The LDL-conjugated diene (CD) lag phase during incubation with Cu(2+) was increased by 157% (110-232%) (median (interquartile range)) (P<0.05) on vitamin E (200 mg/day) and by 235% (185-259%) (P<0.0001) on 400 mg/day. The lag phases for LDL-lipid peroxide (LPO) generation were also significantly increased by 146% (122-192%) (P<0.005) and 177% (101-267%) (P<0.005), respectively. The HDL-CD lag phase also increased on both doses 140% (115-169%) (P<0.005) and 171% (122-192%) (P<0.005), as did the HDL-LPO lag phase by 123% (104-153%) (P<0.05) on 200 mg/day and 240% (97-360%) (P<0.005) on 400 mg daily. Cholesteryl ester transfer activity from HDL to very low and low density lipoproteins significantly increased from 12. 7+/-2.6 (mean+/-SEM) to 16+/-3.4 nmol/ml/h (P<0.05) on 200 mg/daily and 10.4+/-2.0 to 19.2+/-3.3 nmol/ml/h (P<0.005) on vitamin E, 400mg day. Thus, vitamin E (200 and 400mg daily) significantly decreased the susceptibility of LDL and HDL to oxidation in vitro. However, the increase in CETA

  14. Increased von Willebrand factor levels in patients with systemic lupus erythematosus reflect inflammation rather than increased propensity for platelet activation

    PubMed Central

    Raymond, Warren D; Eilertsen, Gro Østli

    2016-01-01

    Background von Willebrand factor (VWF) is involved in platelet plug formation and protein transport. Increased VWF levels in systemic lupus erythematous (SLE) are considered risk factors for vascular events. VWF protein levels, however, do not accurately reflect its platelet-aggregating function, which has not been examined in SLE. Methods Cross-sectional study with clinical and laboratory data obtained in patients with SLE (n=92) from a regional lupus registry. VWF function was determined by ristocetin-induced platelet aggregation (VWF ristocetin cofactor, VWF:RCo) and VWF levels by turbidimetric assay (VWF antigen, VWF:Ag). The platelet-aggregating activity per VWF unit was estimated by the VWF RCo/Ag ratio. Healthy controls served as comparators and associations were evaluated by non-parametric methods. Results VWF:Ag (142% vs 107%, p=0.001) and VWF:RCo levels (123% vs 78%, p<0.041) were increased in patients with SLE, but VWF RCo/Ag ratio was similar as in controls (0.83 vs 0.82, p=0.8). VWF:Ag levels were higher in patients experiencing serositis but unrelated to other manifestations, thrombotic disease, Systemic Lupus Erythematous Disease Activity Index 2000 or Systemic Lupus International Collaborative Clinics-Damage Index. VWF:Ag levels correlated significantly with VWF:RCo levels (Rs 0.8, p<0.001), erythrocyte sedimentation rate (ESR) (Rs 0.32, p<0.01), anti-dsDNA Ab (Rs 0.27, p<0.01), total IgG (Rs 0.33 p<0.01), fibrinogen (Rs 0.28, p<0.01) and ceruloplasmin (Rs 0.367, p<0.01) levels. VWF:RCo levels were not related to clinical findings but were correlated with ESR, anti-dsDNA and transferrin levels. No serological associations existed for VWF RCo/Ag ratio (all p>0.2). Conclusions In this SLE cohort, VWF:Ag behaved similarly to acute-phase reactants, but VWF:Ag increases were not matched by increases in functional activity per unit of VWF. Thus, more VWF did not increase the propensity for platelet aggregation in SLE. PMID:27651919

  15. Identification and Expression of Acetylcholinesterase in Octopus vulgaris Arm Development and Regeneration: a Conserved Role for ACHE?

    PubMed

    Fossati, Sara Maria; Candiani, Simona; Nödl, Marie-Therese; Maragliano, Luca; Pennuto, Maria; Domingues, Pedro; Benfenati, Fabio; Pestarino, Mario; Zullo, Letizia

    2015-08-01

    Acetylcholinesterase (ACHE) is a glycoprotein with a key role in terminating synaptic transmission in cholinergic neurons of both vertebrates and invertebrates. ACHE is also involved in the regulation of cell growth and morphogenesis during embryogenesis and regeneration acting through its non-cholinergic sites. The mollusk Octopus vulgaris provides a powerful model for investigating the mechanisms underlying tissue morphogenesis due to its high regenerative power. Here, we performed a comparative investigation of arm morphogenesis during adult arm regeneration and embryonic arm development which may provide insights on the conserved ACHE pathways. In this study, we cloned and characterized O. vulgaris ACHE, finding a single highly conserved ACHE hydrophobic variant, characterized by prototypical catalytic sites and a putative consensus region for a glycosylphosphatidylinositol (GPI)-anchor attachment at the COOH-terminus. We then show that its expression level is correlated to the stage of morphogenesis in both adult and embryonic arm. In particular, ACHE is localized in typical neuronal sites when adult-like arm morphology is established and in differentiating cell locations during the early stages of arm morphogenesis. This possibility is also supported by the presence in the ACHE sequence and model structure of both cholinergic and non-cholinergic sites. This study provides insights into ACHE conserved roles during processes of arm morphogenesis. In addition, our modeling study offers a solid basis for predicting the interaction of the ACHE domains with pharmacological blockers for in vivo investigations. We therefore suggest ACHE as a target for the regulation of tissue morphogenesis.

  16. Inhibition effect of graphene oxide on the catalytic activity of acetylcholinesterase enzyme.

    PubMed

    Wang, Yong; Gu, Yao; Ni, Yongnian; Kokot, Serge

    2015-11-01

    Variations in the enzyme activity of acetylcholinesterase (AChE) in the presence of the nano-material, graphene oxide (GO), were investigated with the use of molecular spectroscopy UV-visible and fluorescence methods. From these studies, important kinetic parameters of the enzyme were extracted; these were the maximum reaction rate, Vm , and the Michaelis constant, Km . A comparison of these parameters indicated that GO inhibited the catalytic activity of the AChE because of the presence of the AChE-GO complex. The formation of this complex was confirmed with the use of fluorescence data, which was resolved with the use of the MCR-ALS chemometrics method. Furthermore, it was found that the resonance light-scattering (RLS) intensity of AChE changed in the presence of GO. On this basis, it was demonstrated that the relationship between AChE and GO was linear and such models were used for quantitative analyses of GO.

  17. New-generation radiotracers for nAChR and NET.

    PubMed

    Ding, Yu-Shin; Fowler, Joanna

    2005-10-01

    Advances in radiotracer chemistry and instrumentation have merged to make positron emission tomography (PET) a powerful tool in the biomedical sciences. Positron emission tomography has found increased application in the study of drugs affecting the brain and whole body, including the measurement of drug pharmacokinetics (using a positron-emitter-labeled drug) and drug pharmacodynamics (using a labeled tracer). Thus, radiotracers are major scientific tools enabling investigations of molecular phenomena, which are at the heart of understanding human disease and developing effective treatments; however, there is evidently a bottleneck in translating basic research to clinical practice. In the meantime, the poor ability to predict the in vivo behavior of chemical compounds based on their log P's and affinities emphasizes the need for more knowledge in this area. In this article, we focus on the development and translation of radiotracers for PET studies of the nicotinic acetylcholine receptor (nAChR) and the norepinephrine transporter (NET), two molecular systems that urgently need such an important tool to better understand their functional significance in the living human brain.

  18. Acute toxicity of a commercial glyphosate formulation on European sea bass juveniles (Dicentrarchus labrax L.): gene expressions of heme oxygenase-1 (ho-1), acetylcholinesterase (AChE) and aromatases (cyp19a and cyp19b).

    PubMed

    Prevot-D'Alvise, N; Richard, S; Coupé, S; Bunet, R; Grillasca, J P

    2013-12-31

    Acute toxicity of Roundup, a commercial glyphosate--based herbicide, was evaluated in a teleost marine fish, the European sea bass, after 96 h of exposure. The LC50 96-h value of Roundup was 529 mg/L. Juveniles (Dicentrarchus labrax L.) were exposed to a sublethal concentration (35% of the LC50, i.e. 193 mg/L) of Roundup for 96-h. The study of heme oxygenase-1 (ho-1) gene expression was performed in four tissues (liver, gills, brain and gonads) and highlighted the disruption of antioxidant defence system. Results showed that ho-1 mRNA levels in liver and gills significantly decreased (p<0.001 and p<0.01 respectively) in fish exposed to 193 mg/L of Roundup, whereas in brain and gonads, ho-1 mRNA level was not altered. The analysis of acetylcholinesterase expression was used to evaluate the overall neurotoxicity of the herbicide and aromatase genes to assess the alteration of the endocrine system. Results showed that AChE and cyp19b gene transcriptions significantly increased (p<0.01) in brain of sea bass, whereas aromatase gene expression (cyp19a) in gonads was not significantly altered. Our results showed complex tissue-specific transcriptional responses after 96 h of exposure to a sublethal concentration. All these disruptions confirmed the deleterious effects of this glyphosate-based herbicide in a marine species.

  19. Atomic interactions of neonicotinoid agonists with AChBP: Molecular recognition of the distinctive electronegative pharmacophore

    SciTech Connect

    Talley, Todd T.; Harel, Michal; Hibbs, Ryan E.; Radi, Zoran; Tomizawa, Motohiro; Casida, John E.; Taylor, Palmer

    2008-07-28

    Acetylcholine-binding proteins (AChBPs) from mollusks are suitable structural and functional surrogates of the nicotinic acetylcholine receptors when combined with transmembrane spans of the nicotinic receptor. These proteins assemble as a pentamer with identical ACh binding sites at the subunit interfaces and show ligand specificities resembling those of the nicotinic receptor for agonists and antagonists. A subset of ligands, termed the neonicotinoids, exhibit specificity for insect nicotinic receptors and selective toxicity as insecticides. AChBPs are of neither mammalian nor insect origin and exhibit a distinctive pattern of selectivity for the neonicotinoid ligands. We define here the binding orientation and determinants of differential molecular recognition for the neonicotinoids and classical nicotinoids by estimates of kinetic and equilibrium binding parameters and crystallographic analysis. Neonicotinoid complex formation is rapid and accompanied by quenching of the AChBP tryptophan fluorescence. Comparisons of the neonicotinoids imidacloprid and thiacloprid in the binding site from Aplysia californica AChBP at 2.48 and 1.94 {angstrom} in resolution reveal a single conformation of the bound ligands with four of the five sites occupied in the pentameric crystal structure. The neonicotinoid electronegative pharmacophore is nestled in an inverted direction compared with the nicotinoid cationic functionality at the subunit interfacial binding pocket. Characteristic of several agonists, loop C largely envelops the ligand, positioning aromatic side chains to interact optimally with conjugated and hydrophobic regions of the neonicotinoid. This template defines the association of interacting amino acids and their energetic contributions to the distinctive interactions of neonicotinoids.

  20. Increasing Physical Activity during the School Day through Physical Activity Classes: Implications for Physical Educators

    ERIC Educational Resources Information Center

    Adkins, Megan; Bice, Matt; Bartee, Todd; Heelan, Kate

    2015-01-01

    Across the nation schools are adopting health and wellness policies, specifically physical activity (PA) initiatives that aid healthy long-term lifestyles. Interest has been generated about the inclusion of physical activity classes to complement existing physical education classes. Furthermore, discussion has evolved as to if additional…

  1. Decreasing Stereotypy in Preschoolers with Autism Spectrum Disorder: The Role of Increased Physical Activity and Function

    ERIC Educational Resources Information Center

    McLaughlin, Constance Ann Hylton

    2010-01-01

    This study used increased physical activity during recess to reduce stereotypy in preschoolers with Autism Spectrum Disorder. Results indicate increasing physical activity can be used as an intervention to reduce automatically maintained stereotypy in preschoolers with ASD. The intervention had a lesser effect on a preschooler whose stereotypy was…

  2. Men on the Move: A Pilot Program to Increase Physical Activity among African American Men

    ERIC Educational Resources Information Center

    Griffith, Derek M.; Allen, Julie Ober; Johnson-Lawrence, Vicki; Langford, Aisha

    2014-01-01

    Despite the important contribution increasing physical activity levels may play in reducing chronic disease morbidity and mortality, there is a paucity of interventions and research indicating how to improve physical activity levels in African American men. "Men on the Move" was a pilot study to increase African American men's levels of…

  3. Evidence-Based Practice Guideline: Increasing Physical Activity in Schools--Kindergarten through 8th Grade

    ERIC Educational Resources Information Center

    Bagby, Karen; Adams, Susan

    2007-01-01

    Because of the growing obesity epidemic across all age groups in the United States, interventions to increase physical activity and reduce sedentary behaviors have become a priority. Evidence is growing that interventions to increase physical activity and reduce sedentary behaviors have positive results and are generally inexpensive to implement.…

  4. Increasing Activity Attendance and Engagement in Individuals with Dementia Using Descriptive Prompts

    ERIC Educational Resources Information Center

    Brenske, Shasta; Rudrud, Eric H.; Schulze, Kimberly A.; Rapp, John T.

    2008-01-01

    The effects of providing descriptive prompts to increase activity attendance and engagement in 6 individuals with dementia were evaluated using a reversal design. The results showed that providing descriptive prompts increased activity attendance and engagement for all participants. The results support the use of antecedent interventions for…

  5. In vivo interactions between α7 nicotinic acetylcholine receptor and nuclear peroxisome proliferator-activated receptor-α: Implication for nicotine dependence.

    PubMed

    Jackson, Asti; Bagdas, Deniz; Muldoon, Pretal P; Lichtman, Aron H; Carroll, F Ivy; Greenwald, Mark; Miles, Michael F; Damaj, M Imad

    2017-03-07

    Chronic tobacco use dramatically increases health burdens and financial costs. Limitations of current smoking cessation therapies indicate the need for improved molecular targets. The main addictive component of tobacco, nicotine, exerts its dependency effects via nicotinic acetylcholine receptors (nAChRs). Activation of the homomeric α7 nAChR reduces nicotine's rewarding properties in conditioned place preference (CPP) test and i.v. self-administration models, but the mechanism underlying these effects is unknown. Recently, the nuclear receptor peroxisome proliferator-activated receptor type-α (PPARα) has been implicated as a downstream signaling target of the α7 nAChR in ventral tegmental area dopamine cells. The present study investigated PPARα as a possible mediator of the effect of α7 nAChR activation in nicotine dependence. Our results demonstrate the PPARα antagonist GW6471 blocks actions of the α7 nAChR agonist PNU282987 on nicotine reward in an unbiased CPP test in male ICR adult mice. These findings suggests that α7 nAChR activation attenuates nicotine CPP in a PPARα-dependent manner. To evaluate PPARα activation in nicotine dependence we used the selective and potent PPARα agonist, WY-14643 and the clinically used PPARα activator, fenofibrate, in nicotine CPP and we observed attenuation of nicotine preference, but fenofibrate was less potent. We also studied PPARα in nicotine dependence by evaluating its activation in nicotine withdrawal. WY-14643 reversed nicotine withdrawal signs whereas fenofibrate had modest efficacy. This suggests that PPARα plays a role in nicotine reward and withdrawal and that further studies are warranted to elucidate its function in mediating the effects of α7 nAChRs in nicotine dependence.

  6. Growth and erosion of amorphous carbon (a-C:H) films by low-temperature laboratory plasmas containing H and N mixtures

    NASA Astrophysics Data System (ADS)

    Schwarz-Selinger, Thomas; Hopf, Christian; Sun, Chao; Jacob, Wolfgang

    2007-06-01

    Growth and erosion of amorphous hydrogenated carbon (a-C:H) films from nitrogen-containing gas mixtures was studied in an electron-cyclotron-resonance low-temperature plasma. Deposition and erosion rates were measured as a function of nitrogen admixture and ion energy. At low energy, N2 addition to methane plasmas causes a reduction of the deposition rates that does not exceed significantly the expected reduction due to dilution. At higher ion energies the deposition rate reduces further and finally switches to net erosion. Erosion of a-C:H films in N2/H2 mixtures is much more efficient than in pure H2 and N2. The erosion rate drops with increasing N2 admixture almost proportional to the total ion flux if the substrate is at floating potential. For higher ion energies the erosion rate dramatically increases and shows a clear maximum at around 25% N2 flow ratio.

  7. Evidence-based practice guideline: increasing physical activity in schools--kindergarten through 8th grade.

    PubMed

    Bagby, Karen; Adams, Susan

    2007-06-01

    Because of the growing obesity epidemic across all age groups in the United States, interventions to increase physical activity and reduce sedentary behaviors have become a priority. Evidence is growing that interventions to increase physical activity and reduce sedentary behaviors have positive results and are generally inexpensive to implement. National and international health organizations are calling for a comprehensive approach for reducing obesity in children that includes increasing physical activity in the school setting. Although the call to increase activity levels in schools is clear, little guidance has been given to schools on specific methods to accomplish this task. This article provides an overview of an evidence-based guideline developed by a physical education teacher and a school nurse to provide inexpensive, easy-to-implement, effective strategies to increase physical activity in students. Tools are also included in the guideline to measure the effectiveness of the intervention.