Search results for "cholinesterase"
showing 10 items of 148 documents
Pre-invasion history and demography shape the genetic variation in the insecticide resistance-related acetylcholinesterase 2 gene in the invasive Col…
2012
Abstract Background Invasive pest species offers a unique opportunity to study the effects of genetic architecture, demography and selection on patterns of genetic variability. Invasive Colorado potato beetle (Leptinotarsa decemlineata) populations have experienced a rapid range expansion and intense selection by insecticides. By comparing native and invasive beetle populations, we studied the origins of organophosphate (OP) resistance-associated mutations in the acetylcholinesterase 2 (AChE2) gene, and the role of selection and demography on its genetic variability. Results Analysis of three Mexican, two US and five European populations yielded a total of 49 haplotypes. Contrary to the exp…
Impaired formation of the inner retina in an AChE knockout mouse results in degeneration of all photoreceptors
2004
Blinding diseases can be assigned predominantly to genetic defects of the photoreceptor/pigmented epithelium complex. As an alternative, we show here for an acetylcholinesterase (AChE) knockout mouse that photoreceptor degeneration follows an impaired development of the inner retina. During the first 15 postnatal days of the AChE-/- retina, three major calretinin sublaminae of the inner plexiform layer (IPL) are disturbed. Thereby, processes of amacrine and ganglion cells diffusely criss-cross throughout the IPL. In contrast, parvalbumin cells present a nonlaminar IPL pattern in the wild-type, but in the AChE-/- mouse their processes become structured within two 'novel' sublaminae. During t…
Von der symptomatischen zur kausalen Therapie?
2009
Until today the pharmacological therapy of Alzheimer’s disease (AD) is still limited to symptomatic temporary improvement or stabilization of cognitive performance and activities of daily living, and the reduction of neuropsychiatric symptoms of the disease. Available symptomatic treatment options are the acetylcholinesterase inhibitors (ACh-I) donepezil, galantamine, rivastigmine, and the partial N-Methyl-D-Aspartat-(NMDA)-antagonist memantine. Further substances with symptomatic targets, especially selective acetylcholine and histamine receptors, are currently under development. Numerous of disease-modifying substances mainly targeting components of the amyloidogenic pathway of AD are pre…
Galantamine is an allosterically potentiating ligand of the human α4/β2 nAChR
2000
Galantamine (ReminyI ) is a novel drug treatment for mild to moderate Alzheimer's disease (AD). Originally established as a reversible inhibitor of the acetylcholine-degrading enzyme acetylcholinesterase (AChE), galantamine also acts as an allosterically potentiating ligand (APL) on nicotinic acetylcholine receptors (nAChR). Having previously established this second mode of action on nAChRs from murine brain, we demonstrate here the same action of galantamine on the most abundant nAChR in the human brain, the α4/β2 subtype. This nAChR-sensitizing action is not a common property of all, or most, AChE inhibitors, as is shown by the absence of this effect for other therapeutically applied AChE…
Seasonal screening of AChE, GSH and gonad histology, in European sea bassDicentrarchus labraxL. reared in three different fish farms
2013
The aim of this work was to do a preliminary seasonal screening of ecotoxicological biomarkers in European sea bass Dicentrarchus labrax in three different fish farms, to know if the different location and typology can discriminate them. A set of selected biomarkers of xenobiotic exposure, such as acetylcholinesterase (AChE) activity, Glutathione (GSH) and gonad morphology were investigated seasonally in male European sea bass D. labrax (L.) reared in three different intensive farms: a land-based farm of cement tanks (T), an in-shore sea cages farm (C1) and an off-shore sea cages farm (C2). The results showed that both location and typology can discriminate AChE activity, GSH content and go…
A biochemical study of the effects of tributyltin on unfertilized eggs, embryos and larvae of the sea squirt Ciona intestinalis
2009
We have used unfertilized eggs, embryos and larvae of the sea squirt Ciona intestinalis (Ascidiacea, Urochordata) to study the effects of tributyltin (TBT) on acetylcholine esterase (AChE) activity. Our results showed an increase of AChE enzyme activity levels after TBT exposure in both unfertilized eggs and embryos. The effects of TBT were more pronounced during the gastrula stage, while no differences between exposed larvae and controls were observed. A mechanism of TBT action on enzyme activity during ascidian embryonic development and the possibility of employing AChE in C. intestinalis as a biomarker of TBT exposure are suggested and discussed.
Effect of sublethal concentrations of copper sulphate on seabreamSparus auratafingerlings
2007
The gilthead seabream is the most important Mediterranean aquacultured fish species. The main objective of this study was to investigate whether copper sulphate bath treatments used routinely in aquaculture have effects on important physiological functions of early life stages of the gilthead seabream (Sparus aurata). Fingerlings (80-90 days, 0.27 ± 0.06 g) were exposed to copper sulphate baths at 0, 0.25, 0.5 and 1.5 mg L −1 during 24 h. Effects on the central nervous function were evaluated analysing brain acetylcholinesterase activity (AChE). Oxidative stress was assessed by the quantification of lipid peroxidation (LP). Heat shock proteins (HSP70) were used as a general response to chem…
Expression and possible functions of the cholinergic system in a murine embryonic stem cell line.
2007
The expression of a cholinergic system during embryonic development is a widespread phenomenon. However, no precise function could be assigned to it during early pre-neural stages and there are only few studies that document when it precisely starts to be expressed. Here, we examined the expression of cholinergic components in a murine embryonic stem cell line by RT-PCR, histochemistry, and enzyme activity measurements; the acetylcholine (ACh) content was measured by HPLC. We have demonstrated that embryonic stem cells express ACh, acetylcholine receptors, choline acetyltransferase (ChAT), acetyl- and butyryl-cholinesterase (AChE and BChE). Butyryl-cholinesterase (BChE) expression was highe…
Effect of bioclimatic area on the composition and bioactivity of Tunisian Rosmarinus officinalis essential oils
2014
The chemical composition of eight Tunisian Rosmarinus officinalis L. populations (A-H) from different bioclimatic areas has been examined by gas chromatography (GC) and GC-mass spectrometry. The essential oils are characterised by high amounts of oxygenated monoterpenes (58.2-71.7%) followed by monoterpene hydrocabons (15.1-26.7%). 1,8-Cineole, camphor, α-pinene and borneol are the main representative components. The antioxidant activity was investigated by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), ferric reducing ability power assay and β-carotene bleaching test. Samples showed antiradical activity by inhibiting DPPH radical with IC50 values ranging from 375.3 to 592.8 μg mL(- 1) for s…
Acetylcholinesterase activity in juvenileCiona intestinalis(Ascidiacea, Urochordata) after exposure to tributyltin
2012
The acetylcholinesterase (AChE) activity has been studied in 4-day post-fertilization juveniles of Ciona intestinalis exposed to tributyltin (TBT) at 10-5 M using the histochemical method of Karnovsky and Roots. Relative to vertebrate tissues and organs, the development of adult form of ascidians is interesting, because the analysis of many nuclear genes indicated that the ascidians are the closest living relatives of the vertebrates. Therefore, toxicity research using different approaches could provide data for comparative studies with vertebrates. AChE is over-expressed under chemical stress and in some diseases of vertebrates. Therefore, AChE is considered a biomarker of environmental co…