Acetylcholinesterase inhibitors are the most frequently prescribed anti-Alzheimer's drugs. A series of 5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid ethyl ester derivatives as the novel acetylcholinesterase inhibito...Acetylcholinesterase inhibitors are the most frequently prescribed anti-Alzheimer's drugs. A series of 5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid ethyl ester derivatives as the novel acetylcholinesterase inhibitors was designed based on virtual screening methods. The target compounds were synthesized with Biginelli reaction and Hantzsch-type condensation of dihydropyrimidines with substituted phenacyl chlorides, and were characterized with elemental analysis, IR, MS, ^1H NMR, and ^13C NMR. The biological evaluation against human acetylcholinesterase in vitro indicated all the target compounds show more than 50% inhibition at 10μmol/L by means of the Ellman method. The results provide a starting point for the development of novel drugs to treat Alzheimer's disease and lay the foundation of searching for improved acetylcholinesterase inhibitors with the novel scaffolds.展开更多
Bromination is used as a strategy to improve biological activity in medicinal chemistry.In order to study on the structure-activity relationships of the novel acetylcholinesterase inhibitors with 7H-thiazolo[3,2-b]-1,...Bromination is used as a strategy to improve biological activity in medicinal chemistry.In order to study on the structure-activity relationships of the novel acetylcholinesterase inhibitors with 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one scaffold,based on our previous work and molecular modeling,a series of novel 3-aryl-6-(bromoarylrnethyl)-7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives were designed by molecular docking,synthesized and characterized by mass spectra,infrared spectra,proton NMR and elemental analyses.The study of AChE inhibitory activity was carried out using the Ellman colorimetric assay with huperzine-A as the positive control.Most of all target compounds exhibited more than 45%inhibition at 10μmol/L.The preliminary structureactivity relationship was the bromine atoms and the hydroxyl group at the phenyl ring at the C6 position of the parent nucleus played significant roles in the AChE inhibitory activity of the target compounds.展开更多
Acetylcholinesterase inhibitors played significant roles in treatment of Alzheimer's disease.Based on the research foundation of our previous work and molecular modeling,twelve 3,6-diaryl-7H-thiazolo[3,2-b][1,2,4]...Acetylcholinesterase inhibitors played significant roles in treatment of Alzheimer's disease.Based on the research foundation of our previous work and molecular modeling,twelve 3,6-diaryl-7H-thiazolo[3,2-b][1,2,4]triazin-7-one derivatives were synthesized and characterized by mass spectra,infrared spectra,NMR and elemental analyses.The study of AChE inhibitory activity was carried out using the Ellman colorimetric assay with huperzine-A as the positive control.All target compounds exhibited more than 40% inhibition at 10 μM.Some target compounds showed good inhibition against AChE.The preliminary structure-activity relationships were the halogen atoms at the phenyl ring at the C6 position,the hydroxy groups and the long side chains at the phenyl ring at the C3 position of the parent nucleus played significant roles in the AChE inhibitory activity of the target compounds.展开更多
There are few pharmacologic options for the treatment of cognitive deficits associated with traumatic brain injury in pediatric patients.Acetylcholinesterase inhibitors such as donepezil have been evaluated in adult p...There are few pharmacologic options for the treatment of cognitive deficits associated with traumatic brain injury in pediatric patients.Acetylcholinesterase inhibitors such as donepezil have been evaluated in adult patients after traumatic brain injury,but relatively less is known about the effect in pediatric populations.The goal of this review is to identify knowledge gaps in the efficacy and safety of acetylcholinesterase inhibito rs as a potential a djuvant treatment fo r neurocognitive decline in pediatric patients with traumatic brain injury.Investigators queried PubMed to identify literature published from database inception thro ugh June 2023 desc ribing the use of donepezil in young adult traumatic brain injury and pediatric patients with predefined conditions.Based on preselected search criteria,340 unique papers we re selected for title and abstra ct screening.Thirty-two reco rds were reviewed in full after eliminating preclinical studies and pape rs outside the scope of the project.In adult traumatic brain injury,we review results from 14 papers detailing 227 subjects where evidence suggests donepezil is well tole rated and shows both objective and patient-reported efficacy for reducing cognitive impairment.In children,3 pape rs report on 5 children recovering from traumatic brain injury,showing limited efficacy.An additional 15 pediatric studies conducted in populations at risk for cognitive dysfunction provide a broader look at safety and efficacy in 210 patients in the pediatric age group.Given its promise for efficacy in adults with traumatic brain injury and tole rability in pediatric patients,we believe further study of donepezil for children and adolescents with traumatic brain injury is warranted.展开更多
AIM: To determine the effect of different concentrations of the acetylcholinesterase (AChE) inhibitors tacrine and donepezil on retinal protection in AChE(+/-) mice (AChE knockout mice) of various ages. METHODS: Cultu...AIM: To determine the effect of different concentrations of the acetylcholinesterase (AChE) inhibitors tacrine and donepezil on retinal protection in AChE(+/-) mice (AChE knockout mice) of various ages. METHODS: Cultured ARPE -19 cells were treated with hydrogen peroxide (H2O2) at concentrations of 0, 250, 500, 1000 and 2000 mu mol/L and protein levels were measured using Western blot. Intraperitoneal injections of tacrine and donepezil (0.1 mg/mL, 0.2 mg/mL and 0.4 mg/mL) were respectively given to AChE4- mice aged 2mo and 4mo and wild-type S129 mice for 7d; phosphate buffered saline (PBS) was administered to the control group. The mice were sacrificed after 30d by cardiac perfusion and retinal samples were taken. AChE(+/-) deficient mice were identified by polymerase chain reaction (PCR) analysis using specific genotyping protocols obtained from the Jackson Laboratory website. H&E staining, immunofluorescence and Western blot were performed to observe AChE protein expression changes in the retinal pigment epithelial (RPE) cell layer. RESULTS: Different concentrations of H2O2 induced AChE expression during RPE cell apoptosis. AChE(+/-) mice retina were thinner than those in wild -type mice (P< 0.05); the retinal structure was still intact at 2mo but became thinner with increasing age(P <0.05); furthermore, AChE'l- mice developed more slowly than wild-type mice (P <0.05). Increased concentrations of tacrine and donepezil did not significantly improve the protection of the retina function and morphology (P >0.05). CONCLUSION: in viva, tacrine and donepezil can inhibit the expression of AChE; the decrease of AChE expression in the retina is beneficial for the development of the retina.展开更多
Alzheimer's disease (AD), a fatal, progressive, neurodegener- ative disorder, is the most common cause of old-age demen- tia, accounting for 50-75% of dementia patients. Early stages of AD are marked by vocabulary ...Alzheimer's disease (AD), a fatal, progressive, neurodegener- ative disorder, is the most common cause of old-age demen- tia, accounting for 50-75% of dementia patients. Early stages of AD are marked by vocabulary shrinkage, spatial disori- entation, depression, apraxia, and deterioration of recent forms of declarative memory. In course of time, the patients require close supervision due to the loss of cognitive and functional abilities, and at the terminal stages of the disease, all forms of memory are severely impaired with the patients needing nursing home care (World Alzheimer Report, 2013).展开更多
Our earlier work showed that hydromethanol extract(HME)of Pleurotus fl orida had antioxidant and anticholinesterase potential.This study aimed at isolating the constituent responsible for the activities.HME was subjec...Our earlier work showed that hydromethanol extract(HME)of Pleurotus fl orida had antioxidant and anticholinesterase potential.This study aimed at isolating the constituent responsible for the activities.HME was subjected to bioactivity guided fractionation using in vitro anti-acetylcholinesterase(Ellman method)and antioxidant(DPPH scavenging assay).The most active constituent was evaluated in vivo employing i.c.v.streptozotocin(STZ)induced dementia in mice.Morris water maze test was used for evaluating memory,followed by biochemical estimations and histopathological studies.Bioactivity guided fractionation resulted in isolation of resveratrol(identifi ed by IR,NMR and MS)and its content in P.fl orida fruiting bodies was 0.0098%(m/m,by a validated TLC densitometric method).It improved STZ induced dementia and neurodegeneration in mice by reducing brain acetylcholinesterase action and oxidative stress.The observed effects might be the presence of resveratrol.Our results further endorse that P.fl orida derived resveratrol can be a promising therapy for Alzheimer’s disease.展开更多
A dammarane derivative dihydrojujubogenin-2-en-1-one, which possesses a skeleton and pharmacophore partially similar to those of Territrem B, a potent AChE inhibitor, was synthesized via three different paths. The ant...A dammarane derivative dihydrojujubogenin-2-en-1-one, which possesses a skeleton and pharmacophore partially similar to those of Territrem B, a potent AChE inhibitor, was synthesized via three different paths. The anti-AChE activity of this compound and related analogue was measured.展开更多
Enzyme-inorganic hybrid nanoflowers(HNFs)have shown excellent sensing capabilities due to their large specific surface area as well as the simplicity and mildness of the preparation process.However,coupling HNFs to el...Enzyme-inorganic hybrid nanoflowers(HNFs)have shown excellent sensing capabilities due to their large specific surface area as well as the simplicity and mildness of the preparation process.However,coupling HNFs to electrodes to fabricate a uniform and controllable enzymatic electrochemical sensing interface remains a challenge.Here,we proposed an aptamer-induced insitu fabrication strategy for preparing an HNF-based electrochemical sensor with ideal performance.Central to this strategy is the introduction of acetylcholinesterase(AChE)-specific binding aptamer(Apt),which induces the in-situ growth of AChE-copper phosphate(Cu_(3)(PO_(4))_(2))HNFs on the surface of carbon paper(CP).In addition,a dense gold nanoparticle(AuNP)layer was electrodeposited on the CP for anchoring Apt and further extending the electroactive surface area.The prepared AChECu_(3)(PO_(4))_(2)HNF/Apt/AuNP/CP biosensor exhibited a wide detection range from 1 to 107 pM for the four organophosphorus inhibitors,including isocarbophos,dichlorvos,methamidophos,and parathion,with detection limits down to 0.016,0.028,0.071,and 0.113 pM,respectively.With the reactivation of pralidoxime chloride,the electrode can still recover 98.1%of the response after five times of repeated use.In real sample detection,the biosensor achieved high recoveries from 96.45%to 100.13%.The detection target may be extendable to other AChE inhibitors(e.g.,drugs for Alzheimer’s disease).This study demonstrates for the first time the feasibility of using aptamers as an inducer to fabricate an electrochemical enzyme sensing interface in-situ.This strategy can be used to fabricate other enzyme-based biosensors and therefore has broader applications.展开更多
Alzheimer' s disease (AD) is the most common cause of dementia, and the only treatment currently available for the disease is acetylcholinesterase inhibitors. Recent progress in understanding the molecular and cell...Alzheimer' s disease (AD) is the most common cause of dementia, and the only treatment currently available for the disease is acetylcholinesterase inhibitors. Recent progress in understanding the molecular and cellular pathophysiology of Alzheimer's disease has suggested possible pharmacological interventions, including acetylcholineseterase inhibitors; secretase inhibitors; cholesterol lowering drugs; metal chelators and amyloid immunization. The objective of this paper is to review the main drugs possibly used for AD and their future therapeutic effects.展开更多
<strong>Objective:</strong> The purpose of the investigation is to determine if a relationship exists between heart rate and urinary biomarkers of chronic, subacute chlorpyrifos pesticide exposure in youth...<strong>Objective:</strong> The purpose of the investigation is to determine if a relationship exists between heart rate and urinary biomarkers of chronic, subacute chlorpyrifos pesticide exposure in youth. <strong>Methods:</strong> Using 2001-2002 NHANES data, a sample of 1233 children ages 6 - 18 was grouped based on detection status of 3,5,6-trichloropyridinol (TCPy) in urine. Radial pulse and brachial pulse were recorded as measures of heart rate by physicians. <em>T</em>-tests and linear regression analyses were performed to test for associations between TCPy concentrations and heart rate. <strong>Results:</strong> None of the associations between TCPy levels and heart rate outcomes were found to be significant. Nonsignificant effects in the TCPy-detected groups included a slightly reduced heart rate in girls, as well as a slightly elevated heart rate in boys when compared to the undetected controls. Neither was there any significant observable difference in heart rate due to detection status in the sample overall. <strong>Conclusions:</strong> At this time, an effect on heart rate attributable to chronic, low-level chlorpyrifos exposure in youth cannot be determined. Children and adolescents detected did not demonstrate a substantial change in pulse measures when compared to controls. It is recommended that subsequent studies examine chlorpyrifos biomarkers as they may relate to other indicators of cardiovascular health.展开更多
Alzheimer's disease, a progressive neurodegenerative disease, affects learning and memory resulting from cholinergic dysfunction. Scopolamine has been employed to induce Alzheimer's disease-like pathology in vivo an...Alzheimer's disease, a progressive neurodegenerative disease, affects learning and memory resulting from cholinergic dysfunction. Scopolamine has been employed to induce Alzheimer's disease-like pathology in vivo and in vitro through alteration of cholinergic system. N-benzylcinnamide (PT-3), purified from Piper submultinerve, has been shown to exhibit neuroprotective properties against amyloid-β-induced neuronal toxicity in rat cortical primary cell culture and to improve spatial learning and memory of aged rats through alleviating oxidative stress. We proposed a hypothesis that PT3 has a neuroprotective effect against scopolamine-induced cholinergic dysfunction. PT-3 (125-200 nM) pretreatment was performed in human neuroblastoma SH-SY5Y cell line following scopolamine induction. PT-3 (125-200 nM) inhibited scopolamine (2 mM)-induced generation of reactive oxygen species, cellular apoptosis, upregutation of ace- tylcholinesterase activity, downregulation of choline acetyltransferase level, and activation of p38 and JNK signalling pathways. These findings revealed the underlying mechanisms of scopolamine-induced Alzheimer's disease-like cellular dysfunctions, which provide evidence for developing drugs for the treatment of this de- bilitating disease.展开更多
The effects ofbis(7)-tacrine, a novel acetylcholinesterase inhibitor, on cognitive impairment and neuronal degeneration induced by permanent ligation of bilateral common carotid arteries (2VO) were investigated using ...The effects ofbis(7)-tacrine, a novel acetylcholinesterase inhibitor, on cognitive impairment and neuronal degeneration induced by permanent ligation of bilateral common carotid arteries (2VO) were investigated using the Morris water maze in rats. Once daily oral administration ofbis(7)-tacrine (0.025, 0.05 and 0.1 mg?kg?1) was started 14 days after 2VO operation. Over a three-week treatmentbis(7)-tacrine effectively reversed 2VO-induced spatial memory deficits in a dose-dependent fashion. Furthermore, histological observation showedbis(7)-tacrine decreased the neuropathological changes in the 2VO rats brain. These results suggest thatbis(7)-tacrine has therapeutic potential for the treatment of dementia caused by chronic cerebral hypoperfusion.展开更多
Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structur...Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structures of the new compounds were confirmed by H-, 1 13C-NMR and MS data. Compounds 10c and 18 showed weak inhibitory effect on AChE at 10-4 mol/L.展开更多
Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound 11c inhibited AChE with the ratio of 70% at 10-4 mol/L. Compounds 5a, 5b, 6a and 11b showed moderate cytotoxicit...Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound 11c inhibited AChE with the ratio of 70% at 10-4 mol/L. Compounds 5a, 5b, 6a and 11b showed moderate cytotoxicity on cultured KB cells at 10-6 mol/L. Compounds 5c and 6b alleviated injury arising from oxygen-glucose deprivation (OGD).展开更多
Chromenones have attracted much attention since they are excellent acetylcholinesterase inhibitor(AChEi).The 1,2,3-triazoles are multifunctional anti-acetylcholinesterase(AChE)agents.In this paper,we report the three-...Chromenones have attracted much attention since they are excellent acetylcholinesterase inhibitor(AChEi).The 1,2,3-triazoles are multifunctional anti-acetylcholinesterase(AChE)agents.In this paper,we report the three-dimensional quantitative structure-activity relationship(3D-QSAR)study of 251,2,3-triazolechromenone derivatives based comparative molecular field analysis(CoMFA)and comparative molecular similarity indices analysis(CoMSIA).To construct CoMFA and CoMSIA models,the 25 active molecules were randomly divided into the training and test sets.The obtained cross-validation Q2 of the CoMFA model,the coefficient of non-cross-validation R2,and the test value F are 0.597,0.994,and 396.726,respectively.The cross-validation Q2 of the CoMSIA model,the coefficient of the non-cross-validation R2,and the test value F are 0.721,0.979,and 131.107,respectively.The predictive correlation coefficient(rpred2)is 0.728 for CoMFA and 0.805 for CoMSIA,which verifies that the model is predictable.Based on the potential maps of CoMFA and CoMSIA,a library containing a set of potent AChEi was designed.The inhibitory potential of the compounds in this library was found to be greater than the inhibitory potential of the most active compounds in the data set.The results obtained from this study laid the foundation for the development of effective drugs for AChEi.展开更多
A new sensitive fluorometric assay method for acetylcholinesterase (ACHE) and its inhibitor was developed us- ing a fluorescent dye, nile red (NR). Due to the fluorescence resonance energy transfer between the NR ...A new sensitive fluorometric assay method for acetylcholinesterase (ACHE) and its inhibitor was developed us- ing a fluorescent dye, nile red (NR). Due to the fluorescence resonance energy transfer between the NR and the gold nanoparticle (AuNPs), the fluorescence was quenched. AChE can break down acetylthiocholine to produce a thiol-bearing compound, thiocholine. In the presence of thiocholine, the nile red is replaced from the AuNPs sur- faces and simultaneously transformed to a derivative of nile red. The fluorescence intensity of the derivative is much stronger than that of the native nile red with the same concentration and its maximum emission wavelength has a blue shift so that the sensor achieves a good signal-to-background ratio. In addition, when organophosphate pesticide (OPs) exists, the activity of AChE can be inhibited, the generation of thiocholine will be prevented and no fluorescence enhancement occurs. The results show that the method is sensitive to AChE and paraoxon with the de- tection limits of 0.2 mU/mL and 0.05 ng/mL, respectively.展开更多
Ten marine sponge species from Rameswaram,southern India were studied for their filamentous fungal symbionts.The results suggest that fungal symbionts of marine sponges are hyperdiverse.Genera such as Acremonium,Alter...Ten marine sponge species from Rameswaram,southern India were studied for their filamentous fungal symbionts.The results suggest that fungal symbionts of marine sponges are hyperdiverse.Genera such as Acremonium,Alternaria,Aspergillus,Cladosporium,Fusarium and Penicillium were frequently isolated;no true marine fungal species were present.Species of Aspergillus were dominant and co-dominant in all the sponges screened.The fungal isolates produced antialgal,antifungal,antioxidant,antibiotic,antiinsect metabolites.A few fungi produced acetylcholinesterase inhibitors.展开更多
文摘Acetylcholinesterase inhibitors are the most frequently prescribed anti-Alzheimer's drugs. A series of 5H-thiazolo[3,2-a]pyrimidine-6-carboxylic acid ethyl ester derivatives as the novel acetylcholinesterase inhibitors was designed based on virtual screening methods. The target compounds were synthesized with Biginelli reaction and Hantzsch-type condensation of dihydropyrimidines with substituted phenacyl chlorides, and were characterized with elemental analysis, IR, MS, ^1H NMR, and ^13C NMR. The biological evaluation against human acetylcholinesterase in vitro indicated all the target compounds show more than 50% inhibition at 10μmol/L by means of the Ellman method. The results provide a starting point for the development of novel drugs to treat Alzheimer's disease and lay the foundation of searching for improved acetylcholinesterase inhibitors with the novel scaffolds.
基金supported by the National Natural Science Foundation ofChina(No.21072130)
文摘Bromination is used as a strategy to improve biological activity in medicinal chemistry.In order to study on the structure-activity relationships of the novel acetylcholinesterase inhibitors with 7H-thiazolo[3,2-b]-1,2,4-triazin-7-one scaffold,based on our previous work and molecular modeling,a series of novel 3-aryl-6-(bromoarylrnethyl)-7H-thiazolo[3,2-b]-1,2,4-triazin-7-one derivatives were designed by molecular docking,synthesized and characterized by mass spectra,infrared spectra,proton NMR and elemental analyses.The study of AChE inhibitory activity was carried out using the Ellman colorimetric assay with huperzine-A as the positive control.Most of all target compounds exhibited more than 45%inhibition at 10μmol/L.The preliminary structureactivity relationship was the bromine atoms and the hydroxyl group at the phenyl ring at the C6 position of the parent nucleus played significant roles in the AChE inhibitory activity of the target compounds.
基金supported by the National Natural Science Foundation of China (NSFC 21072130)
文摘Acetylcholinesterase inhibitors played significant roles in treatment of Alzheimer's disease.Based on the research foundation of our previous work and molecular modeling,twelve 3,6-diaryl-7H-thiazolo[3,2-b][1,2,4]triazin-7-one derivatives were synthesized and characterized by mass spectra,infrared spectra,NMR and elemental analyses.The study of AChE inhibitory activity was carried out using the Ellman colorimetric assay with huperzine-A as the positive control.All target compounds exhibited more than 40% inhibition at 10 μM.Some target compounds showed good inhibition against AChE.The preliminary structure-activity relationships were the halogen atoms at the phenyl ring at the C6 position,the hydroxy groups and the long side chains at the phenyl ring at the C3 position of the parent nucleus played significant roles in the AChE inhibitory activity of the target compounds.
基金Division of Neurology,Cincinnati Children’s Hospital Medical Center(as a Medical Student Scholars Program award to ALM)。
文摘There are few pharmacologic options for the treatment of cognitive deficits associated with traumatic brain injury in pediatric patients.Acetylcholinesterase inhibitors such as donepezil have been evaluated in adult patients after traumatic brain injury,but relatively less is known about the effect in pediatric populations.The goal of this review is to identify knowledge gaps in the efficacy and safety of acetylcholinesterase inhibito rs as a potential a djuvant treatment fo r neurocognitive decline in pediatric patients with traumatic brain injury.Investigators queried PubMed to identify literature published from database inception thro ugh June 2023 desc ribing the use of donepezil in young adult traumatic brain injury and pediatric patients with predefined conditions.Based on preselected search criteria,340 unique papers we re selected for title and abstra ct screening.Thirty-two reco rds were reviewed in full after eliminating preclinical studies and pape rs outside the scope of the project.In adult traumatic brain injury,we review results from 14 papers detailing 227 subjects where evidence suggests donepezil is well tole rated and shows both objective and patient-reported efficacy for reducing cognitive impairment.In children,3 pape rs report on 5 children recovering from traumatic brain injury,showing limited efficacy.An additional 15 pediatric studies conducted in populations at risk for cognitive dysfunction provide a broader look at safety and efficacy in 210 patients in the pediatric age group.Given its promise for efficacy in adults with traumatic brain injury and tole rability in pediatric patients,we believe further study of donepezil for children and adolescents with traumatic brain injury is warranted.
基金Supported by National Natural Science Foundation of China(No.81160118,81400372)Clinical Medicine Research Special-purpose Foundation of China(No.L2012052)+5 种基金Jiangxi Province Sailing Engineering(No.2014022)Science Technology Foundation of Jiangxi Province(No.20151BBG70223)Youth Science Foundation of Jiangxi Province(No.20151BAB215016)Education Department Youth Scientific Research Foundation(No.GJJ14170)Health Development Planning Commission Science Foundation of Jiangxi Province(NO:20155154)Health Department Tradition Chinese Medicine Science and Technology Foundation(No.2010A015,2012A139,2013A073)
文摘AIM: To determine the effect of different concentrations of the acetylcholinesterase (AChE) inhibitors tacrine and donepezil on retinal protection in AChE(+/-) mice (AChE knockout mice) of various ages. METHODS: Cultured ARPE -19 cells were treated with hydrogen peroxide (H2O2) at concentrations of 0, 250, 500, 1000 and 2000 mu mol/L and protein levels were measured using Western blot. Intraperitoneal injections of tacrine and donepezil (0.1 mg/mL, 0.2 mg/mL and 0.4 mg/mL) were respectively given to AChE4- mice aged 2mo and 4mo and wild-type S129 mice for 7d; phosphate buffered saline (PBS) was administered to the control group. The mice were sacrificed after 30d by cardiac perfusion and retinal samples were taken. AChE(+/-) deficient mice were identified by polymerase chain reaction (PCR) analysis using specific genotyping protocols obtained from the Jackson Laboratory website. H&E staining, immunofluorescence and Western blot were performed to observe AChE protein expression changes in the retinal pigment epithelial (RPE) cell layer. RESULTS: Different concentrations of H2O2 induced AChE expression during RPE cell apoptosis. AChE(+/-) mice retina were thinner than those in wild -type mice (P< 0.05); the retinal structure was still intact at 2mo but became thinner with increasing age(P <0.05); furthermore, AChE'l- mice developed more slowly than wild-type mice (P <0.05). Increased concentrations of tacrine and donepezil did not significantly improve the protection of the retina function and morphology (P >0.05). CONCLUSION: in viva, tacrine and donepezil can inhibit the expression of AChE; the decrease of AChE expression in the retina is beneficial for the development of the retina.
基金in part supported by the German Ministry for Education and Research (BMBF) special network program KMU-Innovativ-2
文摘Alzheimer's disease (AD), a fatal, progressive, neurodegener- ative disorder, is the most common cause of old-age demen- tia, accounting for 50-75% of dementia patients. Early stages of AD are marked by vocabulary shrinkage, spatial disori- entation, depression, apraxia, and deterioration of recent forms of declarative memory. In course of time, the patients require close supervision due to the loss of cognitive and functional abilities, and at the terminal stages of the disease, all forms of memory are severely impaired with the patients needing nursing home care (World Alzheimer Report, 2013).
基金The study was funded by University Grants Commission under UGC BSR fellowship scheme(Award no.F.4.25-1/2013-14(BSR)/7-265/2009(BSR))The authors are thankful to Prof.Nirmal Singh and Mr.Pankaj Bhatia,Department of Pharmaceutical Sciences and Drug Research,Punjabi University,Patiala,India for their help in carrying out animal studies.The authors are also thankful to DBTIPLS project(Grant no:BT/PR4548/INF/22/146/2012),Punjabi University,Patiala,Punjab,India for providing HPTLC facility and Department of Pharmaceutical Sciences and Drug Research,Punjabi University,Patiala,India for providing the necessary laboratory facilities for this work.
文摘Our earlier work showed that hydromethanol extract(HME)of Pleurotus fl orida had antioxidant and anticholinesterase potential.This study aimed at isolating the constituent responsible for the activities.HME was subjected to bioactivity guided fractionation using in vitro anti-acetylcholinesterase(Ellman method)and antioxidant(DPPH scavenging assay).The most active constituent was evaluated in vivo employing i.c.v.streptozotocin(STZ)induced dementia in mice.Morris water maze test was used for evaluating memory,followed by biochemical estimations and histopathological studies.Bioactivity guided fractionation resulted in isolation of resveratrol(identifi ed by IR,NMR and MS)and its content in P.fl orida fruiting bodies was 0.0098%(m/m,by a validated TLC densitometric method).It improved STZ induced dementia and neurodegeneration in mice by reducing brain acetylcholinesterase action and oxidative stress.The observed effects might be the presence of resveratrol.Our results further endorse that P.fl orida derived resveratrol can be a promising therapy for Alzheimer’s disease.
文摘A dammarane derivative dihydrojujubogenin-2-en-1-one, which possesses a skeleton and pharmacophore partially similar to those of Territrem B, a potent AChE inhibitor, was synthesized via three different paths. The anti-AChE activity of this compound and related analogue was measured.
基金the National Natural Science Foundation of China(No.31871878).
文摘Enzyme-inorganic hybrid nanoflowers(HNFs)have shown excellent sensing capabilities due to their large specific surface area as well as the simplicity and mildness of the preparation process.However,coupling HNFs to electrodes to fabricate a uniform and controllable enzymatic electrochemical sensing interface remains a challenge.Here,we proposed an aptamer-induced insitu fabrication strategy for preparing an HNF-based electrochemical sensor with ideal performance.Central to this strategy is the introduction of acetylcholinesterase(AChE)-specific binding aptamer(Apt),which induces the in-situ growth of AChE-copper phosphate(Cu_(3)(PO_(4))_(2))HNFs on the surface of carbon paper(CP).In addition,a dense gold nanoparticle(AuNP)layer was electrodeposited on the CP for anchoring Apt and further extending the electroactive surface area.The prepared AChECu_(3)(PO_(4))_(2)HNF/Apt/AuNP/CP biosensor exhibited a wide detection range from 1 to 107 pM for the four organophosphorus inhibitors,including isocarbophos,dichlorvos,methamidophos,and parathion,with detection limits down to 0.016,0.028,0.071,and 0.113 pM,respectively.With the reactivation of pralidoxime chloride,the electrode can still recover 98.1%of the response after five times of repeated use.In real sample detection,the biosensor achieved high recoveries from 96.45%to 100.13%.The detection target may be extendable to other AChE inhibitors(e.g.,drugs for Alzheimer’s disease).This study demonstrates for the first time the feasibility of using aptamers as an inducer to fabricate an electrochemical enzyme sensing interface in-situ.This strategy can be used to fabricate other enzyme-based biosensors and therefore has broader applications.
文摘Alzheimer' s disease (AD) is the most common cause of dementia, and the only treatment currently available for the disease is acetylcholinesterase inhibitors. Recent progress in understanding the molecular and cellular pathophysiology of Alzheimer's disease has suggested possible pharmacological interventions, including acetylcholineseterase inhibitors; secretase inhibitors; cholesterol lowering drugs; metal chelators and amyloid immunization. The objective of this paper is to review the main drugs possibly used for AD and their future therapeutic effects.
文摘<strong>Objective:</strong> The purpose of the investigation is to determine if a relationship exists between heart rate and urinary biomarkers of chronic, subacute chlorpyrifos pesticide exposure in youth. <strong>Methods:</strong> Using 2001-2002 NHANES data, a sample of 1233 children ages 6 - 18 was grouped based on detection status of 3,5,6-trichloropyridinol (TCPy) in urine. Radial pulse and brachial pulse were recorded as measures of heart rate by physicians. <em>T</em>-tests and linear regression analyses were performed to test for associations between TCPy concentrations and heart rate. <strong>Results:</strong> None of the associations between TCPy levels and heart rate outcomes were found to be significant. Nonsignificant effects in the TCPy-detected groups included a slightly reduced heart rate in girls, as well as a slightly elevated heart rate in boys when compared to the undetected controls. Neither was there any significant observable difference in heart rate due to detection status in the sample overall. <strong>Conclusions:</strong> At this time, an effect on heart rate attributable to chronic, low-level chlorpyrifos exposure in youth cannot be determined. Children and adolescents detected did not demonstrate a substantial change in pulse measures when compared to controls. It is recommended that subsequent studies examine chlorpyrifos biomarkers as they may relate to other indicators of cardiovascular health.
基金supported by a joint Mahidol University and The Thailand Research Fund(TRF)grant(IRG5780009)TRF Royal Golden Jubilee Ph.D.Program(grant No.PHD/0175/2552)the Office of the Higher Education Commission,Ministry of Education,Thailand
文摘Alzheimer's disease, a progressive neurodegenerative disease, affects learning and memory resulting from cholinergic dysfunction. Scopolamine has been employed to induce Alzheimer's disease-like pathology in vivo and in vitro through alteration of cholinergic system. N-benzylcinnamide (PT-3), purified from Piper submultinerve, has been shown to exhibit neuroprotective properties against amyloid-β-induced neuronal toxicity in rat cortical primary cell culture and to improve spatial learning and memory of aged rats through alleviating oxidative stress. We proposed a hypothesis that PT3 has a neuroprotective effect against scopolamine-induced cholinergic dysfunction. PT-3 (125-200 nM) pretreatment was performed in human neuroblastoma SH-SY5Y cell line following scopolamine induction. PT-3 (125-200 nM) inhibited scopolamine (2 mM)-induced generation of reactive oxygen species, cellular apoptosis, upregutation of ace- tylcholinesterase activity, downregulation of choline acetyltransferase level, and activation of p38 and JNK signalling pathways. These findings revealed the underlying mechanisms of scopolamine-induced Alzheimer's disease-like cellular dysfunctions, which provide evidence for developing drugs for the treatment of this de- bilitating disease.
文摘The effects ofbis(7)-tacrine, a novel acetylcholinesterase inhibitor, on cognitive impairment and neuronal degeneration induced by permanent ligation of bilateral common carotid arteries (2VO) were investigated using the Morris water maze in rats. Once daily oral administration ofbis(7)-tacrine (0.025, 0.05 and 0.1 mg?kg?1) was started 14 days after 2VO operation. Over a three-week treatmentbis(7)-tacrine effectively reversed 2VO-induced spatial memory deficits in a dose-dependent fashion. Furthermore, histological observation showedbis(7)-tacrine decreased the neuropathological changes in the 2VO rats brain. These results suggest thatbis(7)-tacrine has therapeutic potential for the treatment of dementia caused by chronic cerebral hypoperfusion.
文摘Two series of territrem B analogues (10a-10c and 18) have been designed and synthesized from jujubogenin 5a which was prepared from jujubogenin glycosides 5b obtained from the leaves of Zizyphus jujuba. The structures of the new compounds were confirmed by H-, 1 13C-NMR and MS data. Compounds 10c and 18 showed weak inhibitory effect on AChE at 10-4 mol/L.
文摘Two series of territrem B analogues (6, 11) were designed and synthesized from jujubogenin 2. Compound 11c inhibited AChE with the ratio of 70% at 10-4 mol/L. Compounds 5a, 5b, 6a and 11b showed moderate cytotoxicity on cultured KB cells at 10-6 mol/L. Compounds 5c and 6b alleviated injury arising from oxygen-glucose deprivation (OGD).
文摘Chromenones have attracted much attention since they are excellent acetylcholinesterase inhibitor(AChEi).The 1,2,3-triazoles are multifunctional anti-acetylcholinesterase(AChE)agents.In this paper,we report the three-dimensional quantitative structure-activity relationship(3D-QSAR)study of 251,2,3-triazolechromenone derivatives based comparative molecular field analysis(CoMFA)and comparative molecular similarity indices analysis(CoMSIA).To construct CoMFA and CoMSIA models,the 25 active molecules were randomly divided into the training and test sets.The obtained cross-validation Q2 of the CoMFA model,the coefficient of non-cross-validation R2,and the test value F are 0.597,0.994,and 396.726,respectively.The cross-validation Q2 of the CoMSIA model,the coefficient of the non-cross-validation R2,and the test value F are 0.721,0.979,and 131.107,respectively.The predictive correlation coefficient(rpred2)is 0.728 for CoMFA and 0.805 for CoMSIA,which verifies that the model is predictable.Based on the potential maps of CoMFA and CoMSIA,a library containing a set of potent AChEi was designed.The inhibitory potential of the compounds in this library was found to be greater than the inhibitory potential of the most active compounds in the data set.The results obtained from this study laid the foundation for the development of effective drugs for AChEi.
文摘A new sensitive fluorometric assay method for acetylcholinesterase (ACHE) and its inhibitor was developed us- ing a fluorescent dye, nile red (NR). Due to the fluorescence resonance energy transfer between the NR and the gold nanoparticle (AuNPs), the fluorescence was quenched. AChE can break down acetylthiocholine to produce a thiol-bearing compound, thiocholine. In the presence of thiocholine, the nile red is replaced from the AuNPs sur- faces and simultaneously transformed to a derivative of nile red. The fluorescence intensity of the derivative is much stronger than that of the native nile red with the same concentration and its maximum emission wavelength has a blue shift so that the sensor achieves a good signal-to-background ratio. In addition, when organophosphate pesticide (OPs) exists, the activity of AChE can be inhibited, the generation of thiocholine will be prevented and no fluorescence enhancement occurs. The results show that the method is sensitive to AChE and paraoxon with the de- tection limits of 0.2 mU/mL and 0.05 ng/mL, respectively.
基金TSS and MD acknowledge the financial assistance by Department of Biotechnology(BT/PR10169/AAQ/03/376/2007),New Delhi,Government of India and Dr.G.Sivaleela,Zoological Survey of India,Chennai for identifying the sponge species.
文摘Ten marine sponge species from Rameswaram,southern India were studied for their filamentous fungal symbionts.The results suggest that fungal symbionts of marine sponges are hyperdiverse.Genera such as Acremonium,Alternaria,Aspergillus,Cladosporium,Fusarium and Penicillium were frequently isolated;no true marine fungal species were present.Species of Aspergillus were dominant and co-dominant in all the sponges screened.The fungal isolates produced antialgal,antifungal,antioxidant,antibiotic,antiinsect metabolites.A few fungi produced acetylcholinesterase inhibitors.