Effect of Transgenic Bt plus CpTI Cotton on Carboxylesterase and Acetylcholinesterase of Cotton Aphid Aphis gossypii

[Objective] The research aimed to assess the effect of transgenic Bt plus CpTI cotton variety SGK321 on carboxylesterase and acetylcholinesterase of cotton aphid Aphis gossypii and provide theoretical basis for studying the biosafety of transgenic cotton.[Method] Cotton aphids were fed with SGK321 and Shiyuan321（normal parental varieties） for over 40 generations.Enzyme activities were compared between cotton aphids feeding on SGK321 for 1,2,3,41,42 and 43 generations with those on Shiyuan321.[Result] The carboxylesterase activity of cotton aphids feeding on SGK321 for 1 generation was significantly higher than those feeding on Shiyuan321.Acetylcholinesterase activity of cotton aphids feeding on SGK321 for 1,2 and 3 generations were significantly higher than those feeding on Shiyuan321 in the same generation.But there was no significant difference of enzyme activity between cotton aphids feeding on SGK321 for a long term and those feeding on parental cotton.[Conclusion] The cotton aphid that feeding on transgenic Bt plus CpTI cotton SGK321 for a long time has adaptivity to SGK321 by regulating the detoxifying enzyme.

Cloning and Sequencing of Two Acetylcholinesterase cDNA Fragments from Cotton Aphid,Aphis gossypii Glover

Two acetylcholinesterase (AChE) genes cDNA fragments,Ag.acel and Ag.ace2,have been cloned from cotton aphid,Aphis gossypii Glover using degenerate primers with RT-PCR technique.Ag.acel gene cDNA fragment is of 282?bp encoding 94 amino acids,and Ag.ace2 gene cDNA fragment is of 264?bp encoding 88 amino acids.Both two putative AChE genes cDNA fragments share numerous similarities with those cloned from other insects.This is the first report of two AChE cDNA fragment sequences in the insect species,which provided the direct evidence of multiple AChE existence in insects.

Determination of the Activity of Acetylcholinesterase(AChE) in Pardosa astrigera and the Inhibition Effects of Pesticides on Its Activity

[ Objective ] The paper was to systemically study the characteristics of acetyl cholinesterase （ACHE） in Pardosa astrigera, and confirm the occurrence and development of its pesticide resistance and the resistance level, thereby establishing a quick and accurate detection method for enzyme activity. [ Method] The optimal conditions for assaying the activity of AChE in different parts of P. astrigera were determined by orthogonal experiment. The distribution conditions of acetyl cholinesterase （AChE） in different tissues of P. astrigera were further studied, and the sensitivities of the enzyme tO four common pesticides were also determined. [ Result] The optimal condition for assaying the activity of AChE in cephalothorax, abdomen and appendage of P. astrigera was as follows, enzyme concentrations： 12, 18 and 29 g/L; substrate concentrations： 0.6, 1.0 and 1.0 mmol/L; pH value, 7.0; reaction temperatures： 30, 35, 35℃ ; reaction time, 5 rain. AChE was mainly distributed in the cephalothorax of P. astrigera. The specific activity of AChE in the extract solution with Triton X-100 was higher than that in the solution without Triton X-100. The median inhibitory concentrations （IC50） of methomyl, phoxim, betacypermethrin, chlorpyrifos against AChE in the cephalothorax of P. astrigera were 7.76 × 10^-5, 1.76×10^-4, 4.12 ×10^-4 and 4.94 ×10^-4 mol/L, respectively. [ Conclusion] AChEs in P. astrigera were membrane-bounded. The inhibition of four pesticides against AChE in the cephalothorax of P. astrigera had good dese-effect, this indicated that AChE in the cephalothorax of P. astrig- era could be used as the biochemical marker to monitor the contamination of organic phosphorus, carbamate and pyrethroid pesticides in the environment.

The protective role of tacrine and donepezil in the retina of acetylcholinesterase knockout mice

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.

Comparison of Acetylcholinesterase Characteristics Between Resistant and Susceptible Strains of Helicoverpa armigera (Hübner)

The sensitivity of a susceptible and two resistant strains of cotton bollworm, Helicoverpa armigera, to phoxim, malathion and methomyl was determined by a topical application of bioassay method. YG strain, collected from field of Yanggu, Shandong Province of China, possessed 7-, 13- and 20-fold of resistance to the above three antiacetylcholinesterases based on the comparison of LD50 values with a laboratory susceptible strain. There were not significant difference of the specific activity and the Vmax value among the three strains. But the affinity of AChE tO acetylthiocholine （ATCh）, in YG strain was the lowest among the three strains tested. A cDNA encoding partial AChE gene was cloned from the three strains by RT-PCR and there was one nucleotide acid difference between YG strain and other two strains which resulted in no amino acid mutation. This partial AChE gene was used as a probe to perform Southern blot. The results indicated that there was no gene amplification in resistant cotton bollworm. Altered AChE with a decreased sensitivity to inhibitors appeared to be one of important resistance mechanisms in cotton bollworm against OP and carbamate compounds.

3,4-Methylenedioxymethamphetamine(MDMA)Abuse Markedly Inhibits Acetylcholinesterase Activity and Induces Severe Oxidative Damage and Liperoxidative Damage

Objective To investigate whether 3,4-methylenedioxymethamphetamine (MDMA) abuse produces another neurotoxicity which may significantly inhibit the acetylcholinesterase activity and result in severe oxidative damage and liperoxidative damage to MDMA abusers. Methods 120 MDMA abusers (MA) and 120 healthy volunteers (HV) were enrolled in an independent sample control design, in which the levels of lipoperoxide (LPO) in plasma and erythrocytes as well as the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and acetylcholinesterase (AChE) in erythrocytes were determined by spectrophotometric methods. Results Compared with the average values of biochemical parameters in the HV group, those of LPO in plasma and erythrocytes in the MA group were significantly increased (P<0.0001), while those of SOD, CAT, GPX and AChE in erythrocytes in the MA group were significantly decreased (P<0.0001). The Pearson product-moment correlation analysis between the values of AChE and biochemical parameters in 120 MDMA abusers showed that significant linear negative correlation was present between the activity of AChE and the levels of LPO in plasma and erythrocytes (P<0.0005-0.0001), while significant linear positive correlation was observed between the activity of AchE and the activities of SOD, CAT and GPX (P<0.0001). The reliability analysis for the above biochemical parameters reflecting oxidative and lipoperoxidative damages in MDMA abusers suggested that the reliability coefficient (alpha) was 0.8124, and that the standardized item alpha was 0.9453. Conclusion The findings in the present study suggest that MDMA abuse can induce another neurotoxicity that significantly inhibits acetylcholinesterase activity and aggravates a series of free radical chain reactions and oxidative stress in the bodies of MDMA abusers, thereby resulting in severe neural, oxidative and lipoperoxidative damages in MDMA abusers.

In vitro screening for acetylcholinesterase inhibition and antioxidant activity of medicinal plants from southern Africa

Objective:To determine the acetylcholinesterase inhibitory（AChE1） and antioxidant activity of the ethyl acetate and methanol extracts of 12 traditional medicinal plants used in the treatment of neurological disorders.Methods:AChEI activity was determined spectrophotometrically using the Ellman’s colorimetric method.Antioxidant activity was carried out by determining the ability of the extracts to scavenge 2,2-diphenyl-1-picryl hydrazyl（DPPH） and 2,2’-azinobis- 3-ethylbenzothiazoline-6-sulfonic acid（ABTS） radicals.The levels of total phenols,flavonoids and flavonols were determined quantitatively using spectrophotometric methods.Results:AChEI was observed to be dose-dependent.Lannea schweinfurthii（L.schweinfurthii）（Engl.） Engl.and Scadoxus puniceus（S.puniceus）（L.） Friis & I.Nordal.root extracts showed the lowest IC50 value of 0.000 3 mg/mL for the ethyl acetate extracts while Zanthoxylum davyi（Z.davyi）（I.Verd.） P.G. Watermann had the lowest IC50 value of 0.01 mg/mL for the methanol extracts in the AChEI assay. The roots of Piper capense（P.capense） L.f.,L.schweinfurthii,Ziziphus mucronata（Z.mucronata） Willd.,Z.davyi and Crinum bulbispermum（C.bulbispermum）（Burm.f.） Milne-Redh.& Schweick.showed noteworthy radical scavenging activity and good AChEI activity.Conclusions: Five plants show good antioxidant and AChEI activity.These findings support the traditional use of the plants for treating neurological disorders especially where a cholinesterase mechanism and reactive oxygen species（ROS） are involved.

Acute effects of chlorpyryphos-ethyl and secondary treated effluents on acetylcholinesterase and butyrylcholinesterase activities in Carcinus maenas

The acute effects of commercial formulation of chlorpyrifos-ethyl （Dursban ） and the secondary treated industrial/urban effluent （STIUE） exposure on acetylcholinesterase （ACHE） and butyrylcholinesterase （BuChE） activities in hepatopancreas and gills of Mediterranean crab Carcinus maenas were investigated. After 2 d of exposure to chlorpyriphos-ethyl, the AChE activity was inhibited in both organs at concentrations of 3.12 and 7.82 μg/L, whereas the BuCHE was inhibited only at higher concentration 7.82 μg/L of commercial preparation Dursban~. The exposure of crabs to Dursban （3.12 μg/L） showed a significant decrement of ACHE activity at 24 and 48 h, whereas the BuChE was inhibited only after 24 h and no inhibition for both enzymes was observed after 72 h. Moreover, a significant repression of AChE activity was observed in both organs of C. maenas exposed to 5% of STIUE. Our experiments indicated that the measurement of AChE activity in gills and hepatopancreas of C. maenas would be useful biomarker of organophosphorous （OP） and of neurotoxic effects of STIUE in Tunisia.

Acetylcholinesterase inhibitor modifications: a promising strategy to delay the progression of Alzheimer's disease

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）.

Comparisons of Properties of Acetylcholinesterase from Two Field-Collected Populations of Oxya chinensis Thunberg(Orthoptera:Acrididae)and the Role of Acetylcholinesterase in the Susceptibility to Malathion

In this study, acetylcholinesterase (AChE) was extracted from two field-collected populations of Oxya chinensis (XinxiangCity, Henan Province and Changzhi City, Shanxi Province). AChE activities were decreased when concentrations of ATCincreased, showing a characteristic phenomenon of substrate inhibition at high concentration in both populations. Suchinhibition occurred at relatively low concentration for AChE from Xinxiang population but relatively high for AChE fromChangzhi population. The kinetic study showed that there were no significant differences between the two populations inthe Km values. The Km value in Changzhi population was only 1.09-fold higher than that in Xinxiang population. However,significant differences were observed between the two populations in Vmax values. The Vmax value in Changzhi populationwas 1.32-fold higher than that in Xinxiang population. The inhibition study in vitro showed that the AChE from bothpopulations exhibited similar rank order in sensitivity to inhibition by three OPs, as determined by comparison of theirbimolecular rate constants (ki), from the most potent inhibition to the least was chlopyrifos-oxon > paraoxon >demeton-s-methyl for AChE from the two populations and that the ki values in Xinxiang population were lower than those in Changzhipopulation. The I50 values of AChE from Xinxiang population were 4.84-, 2.66-, and 1.92-fold less sensitive to inhibition byparaoxon, chlopyrifos-oxon, and demeton-s-methyl. These results were consistent with the results in bioassay. It isinferred that AChE insensitivity to OP insecticides plays an important role in the differences of insusceptibility of Oxyachinensis to malathion between the two populations.

High-level expression and purification of Plutella xylostella acetylcholinesterase in Pichia pastoris and its potential application

The acetylcholinesterase 2（AChE2）cloned from Plutella xylostella was first successfully expressed in methylotrophic yeast Pichia pastoris GS115.One transformant with high-level expression of the recombinant AChE（rAChE,23.2 U mL-1in supernatant）was selected by plating on increasing concentrations of antibiotic G418 and by using a simple and specific chromogenic reaction with indoxyl acetate as a substrate.The maximum production of r ACh E reached about 11.8 mg of the enzyme protein per liter of culture.The r ACh E was first precipitated with ammonium sulfate（50%saturation）and then purified with procainamide affinity column chromatography.The enzyme was purified 12.1-fold with a yield of 22.8%and a high specific activity of 448.3 U mg-1.It was sensitive to inhibition by methamidophos and pirimicarb,the calculated 50% inhibitory concentration（IC50）values of the two pesticides were 0.357 and 0.888 mg L-1,respectively,and the calculated 70% inhibitory concentration（IC70）values were 0.521 and 0.839 mg L-1,respectively.The results suggested that it has a potential application in the detection of pesticide residues.

Acetylcholinesterase function in apoptotic retina pigment epithelial cells induced by H_2O_2

AIM:To investigate the acetylcholinesterase（AChE）expression involved in retina pigment epithelial（RPE）apoptosis induced by higher concentrations H2O2.METHODS:The human retinal pigment epithelium cell line ARPE-19 was from ATCC（Rockville,MD）.Cultured ARPE-19 cells were treated with H2O2 at 0,250,500,1000,2 000μmol/L and cell viability was measured with MTT assay.AChE expression and DNA fragments were analyzed by immunocytochemistry,TUNEL and PARP-1Western blotting.RESULTS:Immunofluorescence detected AChE exist in the normal human retinal tissue.When H2O2】500μmol/L,AChE expression showed an increase after 2h,and this concentration was selected for the present study.RPE cell was induced with 1 000μmoI/L H2O2 for 2h,compared to the control group,cell activity decline detected by MTT,AChE and PARP-1 protein expression was significantly increased detected by Western blotting.AChE immunofluorescence staining was positive in RPE cell after HO2 incubate 2h.In addition,pretreatment with100|jmol/L epigallocatechin gallate（EGCG）,cell viability increased from 31.20%±3.90%to 70.23%±12.96%.CONCLUSION:AChE is weakly expressed in normal human RPE cells.Stimulation with H2O2 caused the stable increase of AChE expression in RPE cells,which may indicate that AChE may be an important role in AMD.

Anti-acetylcholinesterase activity of the aglycones of phenolic glycosides isolated from Leonurus japonicus

Objective: To find the genuine structure with anti-acetylcholinesterase(anti-ACh E) from the phenolic glycosides abundant in Leonurus japonicus(Lamiaceae). The assay for antiACh E activity is often used to lead anti-Alzheimer's drugs.Methods: The five phenolic glycosides, tiliroside, leonurusoside C, 2’’’-syringoylrutin,rutin, and lavanduliofolioside were isolated from L. japonicus. The activities of the glycosides were relatively low. Seven compounds including p-coumaric acid, caffeic acid, hydroxytyrosol, salidroside, syringic acid, kaempferol, and quercetin, which are produced by the hydrolysis of the five glycosides, were also assayed for anti-ACh E activity.Results: Of those seven compounds, the five compounds other than salidroside and syringic acid exhibited potent anti-ACh E activities. In particular, the IC_(50)s of caffeic acid and quercetin were(1.05 ± 0.19) and(3.58 ± 0.02) mg/m L, respectively. Rutin was the most abundant flavonoid in the extract(9.18 mg/g as measured by HPLC).Conclusion: The substances with potent anti-ACh E were caffeic acid, quercetin, pcoumaric acid, kaempferol, and hydroxytyrosol that can be produced from their glycosides.

Effect of propofol on the reactivity of acetylcholinesterase,N-methyl-D-aspartate receptors,and gamma-aminobutyric acid receptors in the hippocampus of aged rats after chronic cerebral ischemia

We induced ischemic brain injury in aging rats to examine the effects of varying doses of propofol on hippocampal activities of acetylcholinesterase, N-methyI-D-aspartate receptors, and y-aminobutyric acid receptors. Propofol exhibited no obvious impact on acetylcholinesterase activity, but directly activated the y-aminobutyric acid receptor. The neuroprotective function of propofol on the hippocampus of aging rats following cerebral ischemic injury may be related to altered activities of y-aminobutyric acid receptors and N-methyI-D-aspartate receptors.

Acetylcholinesterase inhibition ameliorates retinal neovascularization and glial activation in oxygen-induced retinopathy

AIM:To investigate whether inhibition of acetylcholinesterase(AChE)by donepezil ameliorate aberrant retinal neovascularization(RNV)and abnormal glial activation in oxygen-induced retinopathy(OIR).METHODS:A mouse model of RNV was induced in postnatal day 7(P7)mice by exposure to 75%oxygen.Donepezil was administrated to P12 mice by intraperitoneal injection.Expression and localization of AChE in mouse retinas were determined by immunofluorescence.RNV was evaluated by paraffin sectioning and hematoxylin and eosin(HE)staining.Activation of retinal M uller glial cells were examined by immunoblot of glial fibrillary acidic protein(GFAP).rMC-1.a retinal Muller cell line,was used for in vitro study.Expression of hypoxia-induced factor 1α(HIF-1α)and vascular endothelial growth factor(VEGF)were determined by Western-blot analysis,enzyme-linked immunosorbent assay(ELISA)or immunostaining.RESULTS:Aberrant RNV and glial activation was observed after OIR.Of note,retinal AChE was mainly expressed by retinal Muller glial cells and markedly increased in OIR mice.Systemic administration of donepezil significantly reduced RNV and abnormal glial activation in mice with OIR.Moreover,ischemia-induced HIF-1αaccumulation and VEGF upregulation in OIR mouse retinas and cultured rMC-1 were significantly inhibited by donepezil intervention.CONCLUSION:AchE is implicated in RNV with OIR.Inhibition of AChE by donepeizl is likely to be a potential therapeutic approach for retinal neovascular diseases.

Electrochemical Assay of Effects of Organophosphate Poisoning on Acetylcholinesterase from Pheretima via 2,6-Dimethyl-p-benzoquinone

Electroanalytical techniques could be a reliable and promising alternative to classical and sophisticated methods because of their simplicity（small and portable）,easy use,the ability to deliver fast response with high sensitivity and selectivity.A square wave voltammetric method was developed for the assessment of organophosphorus（OPs） compound impact on acetylcholinesterase（AChE） of Pheretima with 2,6-dimethyl-p-benzoquinone（2,6DMBQ） as a redox indicator.The substrate of acetylthiocholine is hydrolyzed by AChE and the produced thiocholine reacts with 2,6-DMBQ to give an obvious shift of electrochemical signal.The reduction peak of 2,6-DMBQ is located at around 0.18 V which is far away from the oxidation potential of possible interference components often present in biosample.The decreased rate of reduction current was related with the activity of AChE.The inhibition of parathion-methyl on AChE was assessed.The inhibiton rate of OPs on AChE activity increased quickly during the first 10 min inhibition,and after that the value of inhibition rate approached to be constant.AChE lost almost 29.3% of activity after 10 min incubation with 1 μg/mL parathion-methyl and 67.5% of activity with 10 μg/mL parathion-methyl,while the activity that corresponds to 40 μg/mL parathion-methyl was nearly completely inhibited（94.9%）.Compared to cyclic voltammetry and amperometry,Square wave voltammetry（SWV） method is a high sensitive electroanalysis with fast scan-rate（only several seconds for one signal value） which is useful to prevent the electrodes from possible fouling or passivation.This method can be employed to assess the inhibition of organophosphate on AChE and investigate OPs impact on environmental animals.

Acetylcholinesterase Biosensor Based on Poly(diallyldimethylammonium chloride)-multi-walled Carbon Nanotubes-graphene Hybrid Film

In this paper, an amperometric acetylcholinesterase(ACh E) biosensor for quantitative determination of carbaryl was developed. Firstly, the poly(diallyldimethy-lammonium chloride)-multi-walled carbon nanotubes-graphene hybrid film was modified onto the glassy carbon electrode(GCE) surface, then ACh E was immobilized onto the modified GCE to fabricate the ACh E biosensor. The morphologies and electrochemistry properties of the prepared ACh E biosensor were investigated by using scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. All variables involved in the preparation process and analytical performance of the biosensor were optimized. Based on the inhibition of pesticides on the ACh E activity, using carbaryl as model compounds, the biosensor exhibited low detection limit, good reproducibility and high stability in a wide range. Moreover, the biosensor can also be used for direct analysis of practical samples, which would provide a new promising tool for pesticide residues analysis.

Design,Synthesis,and Biological Evaluation of 5H-Thiazolo[3,2-a]pyrimidine-6-carboxylic Acid Ethyl Ester Derivatives as a Novel Series of Acetylcholinesterase Inhibitors

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.

Molecular Docking and Design of Novel Heterodimers of Donepezil and Huperzine Fragments as Acetylcholinesterase Inhibitors

To provide hints for the design of new acetylcholinesterase（ACh E） inhibitors with higher potency and specificity, the binding modes of novel heterodimers comprised of donepezil and huperzine A fragments with ACh E were explored by employing the docking simulations. The results show that the binding mode of S-17b（the most potent inhibitor in Ref. 2, i.e., Bioorg. Med. Chem. 2013, 21, 676-683） is clearly different from that of donepezil, while the binding modes of other heterodimers in Ref. 2 are the same as that of donepezil. In addition, based on the binding mode and structure modification of S-17 b, two novel inhibitors（S-17b1 and S-17bb1） with much higher inhibitory potency than S-17 b were obtained. Our design strategy was to replace the hupyridone moiety of S-17 b with the bulky group, and to replace the dimethoxyindanone moiety of S-17 b with more hydrophobic and bulky group with a highly positive charge, which would result in generating potent and selective AChE inhibitors.

Isolation of Pleurotus fl orida derived acetylcholinesterase inhibitor for the treatment of cognitive dysfunction in mice

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.