Role Of Acetylcholinesterase Research Articles

Geniposide and Harpagoside Functionalized Cerium Oxide Nanoparticles as a Potential Neuroprotective.

Alzheimer's disease is associated with protein aggregation, oxidative stress, and the role of acetylcholinesterase in the pathology of the disease. Previous investigations have demonstrated that geniposide and harpagoside protect the brain neurons, and cerium nanoparticles (CeO2 NPs) have potent redox and antioxidant properties. Thus, the effect of nanoparticles of Ce NPs and geniposide and harpagoside (GH/CeO2 NPs) on ameliorating AD pathogenesis was established on AlCl3-induced AD in mice and an aggregation proteins test in vitro. Findings of spectroscopy analysis have revealed that GH/CeO2 NPs are highly stable, nano-size, spherical in shape, amorphous nature, and a total encapsulation of GH in cerium. Treatments with CeO2 NPs, GH/CeO2 NPs, and donepezil used as positive control inhibit fibril formation and protein aggregation, protect structural modifications in the BSA-ribose system, have the ability to counteract Tau protein aggregation and amyloid-β1-42 aggregation under fibrillation condition, and are able to inhibit AChE and BuChE. While the GH/CeO2 NPs, treatment in AD induced by AlCl3 inhibited amyloid-β1-42, substantially enhanced the memory, the cognition coordination of movement in part AD pathogenesis may be alleviated through reducing amyloidogenic pathway and AChE and BuChE activities. The findings of this work provide important comprehension of the chemoprotective activities of iridoids combined with nanoparticles. This could be useful in the development of new therapeutic methods for the treatment of neurodegenerative diseases.

AChE as a spark in the Alzheimer's blaze - Antagonizing effect of a cyclized variant.

The amyloid precursor protein (APP), presenilin 1 (PS1), amyloid beta (Aβ), and GSK3 are the effectors, which are significantly associated with progression of Alzheimer's Disease (AD) and its symptoms. A significant protein, acetylcholinesterase (AChE) becomes dysfunctional as a result of cholinergic neuronal loss in AD pathology. However, certain associated peptides potentiate the release of primary neuropathological hallmarks, i.e., senile plaque and neurofibrillary tangles (NFTs), by modulating the alpha 7 acetylcholinesterase receptor (α7nAChR). The AChE variants, T30 and T14 have also been found to be elevated in AD patients and mimic the toxic actions of pathological events in patients. The manuscript discusses the significance of AChE inhibitors in AD therapeutics, by indicating the disastrous role of molecular alterations and elevation of AChE, accompanied with the downstream effects instigated by the peptide, supported by clinical evidence and investigations. The cyclized variant of AChE peptide, NBP14 has been identified as a novel candidate that reverses the harmful effects of T30, T14 and Aβ, mainly calcium influx, cell viability and AChE release. The review aims to grab the attention of neuro-researchers towards the significance of triggering effectors in propagating AD and role of AChE in regulating them, which can potentially ace the development of reliable therapeutic candidates, similar to NBP14, to mitigate neurodegeneration.

ACETYLCHOLINESTERASE, AS A POTENTIAL BIOMARKER OF NAPHTHALENE TOXICITY IN DIFFERENT TISSUES OF FRESHWATER TELEOST, ANABAS TESTUDINEUS

Naphthalene, a Polycyclic Aromatic Hydrocarbon is widely used as a fumigant and disinfectant despite its toxic effect and is ranked as the ninth most threatening compound. The present study was carried out to determine the in vivo effect of naphthalene at different concentrations on acetylcholinesterase (AChE) enzyme activity in different tissues of Anabas testudineus. The fishes were exposed to varying concentrations of naphthalene (4.2 mgL–1, 4.4 mgL–1, 4.6 mgL–1, 4.8 mgL–1 and 5 mgL–1) for a period of 72 hours. Acetylcholinesterase enzyme activity was found to be significantly inhibited, in a dose-response manner. The inhibition percentage of AChE activity varied from 9.34–43.95% in brain tissue, 2.56–35.81% in liver tissue, 5.94–34.15% in muscle tissue and 3.92–33.75% in gills in comparison to the tissues of the control group. Maximum inhibition of acetylcholinesterase enzyme activity in treated fish was observed in the brain followed by liver, muscles, and gills. This study highlights the significance and role of acetylcholinesterase as a potential stress biomarker of naphthalene toxicity.

Acetylcholinesterase Inhibitors in the Treatment of Neurodegenerative Diseases and the Role of Acetylcholinesterase in their Pathogenesis.

Acetylcholinesterase (AChE) plays an important role in the pathogenesis of neurodegenerative diseases by influencing the inflammatory response, apoptosis, oxidative stress and aggregation of pathological proteins. There is a search for new compounds that can prevent the occurrence of neurodegenerative diseases and slow down their course. The aim of this review is to present the role of AChE in the pathomechanism of neurodegenerative diseases. In addition, this review aims to reveal the benefits of using AChE inhibitors to treat these diseases. The selected new AChE inhibitors were also assessed in terms of their potential use in the described disease entities. Designing and searching for new drugs targeting AChE may in the future allow the discovery of therapies that will be effective in the treatment of neurodegenerative diseases.

Characterization of Acetylcholinesterase from Various Sources: A Mini Re

In this review, various aspects of acetylcholinesterase (AChE) are reviewed. Acetylcholinesterase (AChE, EC3.1.1.7) is an important neurotransmitter because it hydrolyses the neurotransmitter acetylcholine (ACh), it is also the target site of organophosphorus and carbamate insecticides. The discovery of the first neurotransmitter ACh was soon followed by the discovery of its hydrolysing enzyme, AChE. The role of AChE in terminating AChE-mediated neurotransmission made it the focus of intense research for much of the past century. The role of butyrylcholinesterase (BChE) is not known but it is assumed to participate in the growth and development and to scavenge the cholinergic toxins, it is also reported to have an auxiliary role in synaptic transmission. Acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) are the major groups of cholinesterase differentiated by their substrate preferences. Substrate binding specificity and catalytic efficiency are tangled in enzyme catalysis. The fact that an enzyme may exist in more than one molecular form has been accepted for a number of years.

The role of acetylcholinesterase and butyrylcholinesterase activity in the development of delirium in acute stroke.

Our study aimed to test whether plasma acetylcholinesterase and butyrylcholinesterase enzyme activity were related to the presence and intensity of delirium in acute stroke patients. We carried out a matched (age and gender) case-control study, in a sample of consecutive patients with an acute infarct or intracerebral haemorrhage (≤7 days). We assessed delirium using the DSM-5 criteria and the Delirium Rating Scale, and we measured plasma acetylcholinesterase and butyrylcholinesterase enzyme activity after the patient's admission in the stroke unit and before hospital discharge. Mantel-Haenszel's chi-square was used to test bivariate associations between cases (delirious patients) and controls (non-delirious patients). At admission in the stroke unit, cases and controls did not present significant differences in plasma acetylcholinesterase or butyrylcholinesterase activity. At hospital discharge (18 cases and 21 controls) patients who have had delirium at admission had higher levels of butyrylcholinesterase activity. Butyrylcholinesterase activity may secondarily increase due to the inflammatory process associated with neuronal dysfunction in delirium patients.

Acetylcholinesterase staining for the pathological diagnosis of Hirschsprung's disease.

Hirschsprung's disease (HD) is a congenital disease manifesting various degrees of functional bowel obstruction caused by the absence of enteric ganglion cells, which are usually absent in the colonic segment of the HD patient. Because the aganglionic segment of HD always includes the rectum, pathological diagnosis can be made using a rectal sample. HD should be diagnosed as early as possible because serious complications, such as acute enterocolitis or toxic megacolon, can develop without a definitive diagnosis and appropriate treatment. In the mid-1900s, HD was diagnosed by HE staining of specimens obtained by full-thickness biopsy. Since then, the combination of rectal mucosal biopsy and rubeanic acid-amplificated AChE staining has been brought about by the following milestones: the discovery that the submucosal plexus and the intermuscular plexus had the same level of nerve migration; the findings of research on acetylcholine (ACh) and acetylcholinesterase (AChE) in the intestinal tract; and the establishment of a rubeanic acid amplification method. Consequently, the diagnostic rate of HD improved dramatically in the 1980s. This review outlines the history of diagnostic methods for HD, the roles of ACh and AChE in the intestine, and the method of AChE staining.

Neuroprotective effect of red quinoa seeds extract on scopolamine-induced declarative memory deficits in mice: The role of acetylcholinesterase and oxidative stress

Abstract The effect of red quinoa seed extract obtained by soxhlet (RQ-S) on scopolamine (SCP)-induced memory deficits in the object recognition task in mice was evaluated, as well as the involvement of oxidative stress and AChE activity. Four quinoa extracts were obtained: two from white quinoa and two from red quinoa, extracted by soxhlet or shaking. The content of total phenolic compounds (TPC), total flavonoids (TF) and antioxidant activity was determined in the four extracts. The RQ-S showed the highest TPC and TF content and antioxidant activity compared with the others quinoa extracts. The administration of RQ-S prevented memory deficit, changes of AChE activity and oxidative stress indicators (SOD, catalase, TBARS and ROS) induced by SCP, in the hippocampus and partially in the cerebral cortex. These results provide evidence that RQ-S is an alternative to protect SCP-induced memory deficits in mice, and suggest the involvement of oxidative stress and AChE activity.

Respiratory failure triggered by cholinesterase inhibitors may involve activation of a reflex sensory pathway by acetylcholine spillover

Respiration failure during exposure by cholinesterase inhibitors has been widely assumed to be due to inhibition of cholinesterase in the brain. Using a double chamber plethysmograph to measure various respiratory parameters, we observed long “end inspiratory pauses” (EIP) during most exposure that depressed breathing. Surprisingly, Colq KO mice that have a normal level of acetylcholinesterase (AChE) in the brain but a severe deficit in muscles and other peripheral tissues do not pause the breathing by long EIP. In mice, long EIP can be triggered by a nasal irritant. Eucalyptol, an agonist of cold receptor (TRPM8) acting on afferent sensory neurons and known to reduce the EIP triggered by such irritants, strongly reduced the EIP induced by cholinesterase inhibitor. These results suggest that acetylcholine (ACh) spillover from the neuromuscular junction, which is unchanged in Colq KO mice, may activate afferent sensory systems and trigger sensory reflexes, as reversed by eucalyptol. Indeed, the role of AChE at the cholinergic synapses is not only to accurately control the synaptic transmission but also to prevent the spillover of ACh. In the peripheral tissues, the ACh flood induced by cholinesterase inhibition may be very toxic due to interaction with non-neuronal cells that use ACh at low levels to communicate with afferent sensory neurons.

Effect of pregnancy on the cholinergic responses of the bladder: role of acetylcholinesterase.

Pregnancy is associated with many functional changes of the urinary bladder. It was reported that most of healthy women complain from urinary symptoms during pregnancy. The parasympathetic system is mainly mediating bladder emptying. The aim of the study is to investigate the cholinergic effect and the role of acetylcholinesterase in the bladder during pregnancy. Sixteen rats were used in the present study as control group (non-pregnant) and pregnant group (18-20days pregnant). Isolated urinary smooth muscle strips were suspended in organ baths filled with Krebs' solution for isometric tension recording. Electric field stimulation (EFS), (0.1-40Hz), of the control and pregnant bladder preparations produced frequency-dependent contractions. Atropine (1µM) inhibited EFS-induced contractions in the two groups by 65% and 50% respectively indicating the response of cholinergic innervation. Neostigmine significantly enhanced EFS responses, confirming its selectivity for inhibiting acetylcholinesterase which is responsible for termination of acetylcholine. Concentration-response curves for acetylcholine were reduced in pregnant group than control. Concentration-response curves for ATP were increased in pregnant group than control. Neostigmine augmented concentration-response curves for acetylcholine in control and pregnant groups. The effect of neostigmine on acetylcholine contractile responses in pregnancy group was higher than in control. Urinary bladder dysfunction during pregnancy might be due to augmentation of acetylcholinesterase effect. This will lead to the decrease in response to cholinergic stimuli. New pharmaceutical drugs specifically affecting the enzyme in the bladder can help in avoiding the unpleasant urinary symptoms during pregnancy.

The Role of Acetylcholinesterase, Paraxonase, and Oxidative Stress in Breast Tumors

Background: Oxidative stress is associated with the development of a large variety of malignancies. Objectives: This study was conducted to evaluate the acetylcholinesterase (AChE) and arylesterase (ARE) activities, malondialdehyde (MDA), and total antioxidant capacity (TAC) plasma levels in two groups of patient with breast cancer and benign breast diseases compared to healthy volunteers. Methods: The present study was composed of two groups of patients with malignant breast tumors (MBT) and benign breast diseases (BBD), and a control group (CON). Enzyme activities and antioxidants markers were measured, using spectrophotometry. Results: In both case groups, MBT and BBD, ARE was found to show lower activity compared to CON group (P = 0.004 and P = 0.014, respectively). Lower activity of AChE was found in both MBT and BBD compared to CON subjects (P = 0.003 and P = 0.034, respectively). The mean plasma levels of MDA in both groups of patients MBT and BBD were higher than those in CON (P < 0.001 for both comparisons). No significant differences were detected between groups regarding the mean levels of TAC. Conclusions: The results obtained from the current study indicate that healthy subjects show a different redox status than patients with MBT and BBD. Our data suggest that erythrocyte AChE may be considered as an indicator of oxidative stress along with other factors in patients with breast tumors. Thus, consuming antioxidant supplements can be helpful for the prevention of breast diseases.

The inhibition of acetylcholinesterase by a brain-targeting polylysine-ApoE peptide: biochemical and structural characterizations.

The in-trans delivery of protein therapeutics across the blood-brain barrier by K16ApoE peptide carrier has been demonstrated to improve the neurological symptoms and increase the life-span of late-infantile neuronal ceroid lipofuscinosis (LINCL) mice. However, acute toxicity of K16ApoE was observed in LINCL mice resulting in a narrow therapeutic index, limiting the potential of translating the K16ApoE into a viable drug delivery system. This study aims to unravel the toxic mechanism of action. We hypothesized that the toxic response towards the peptide was induced by inhibition of acetylcholinesterase (AChE) activity at neuro-muscular junction. Here, results from the dose-response study suggested that AChE activity was inhibited by K16ApoE at either low or high doses but not at the mid-dose where a significant increase in AChE activity was observed. Meanwhile, molecular docking simulations showed that the N-terminus of K16ApoE is capable of binding to the active site gorge of AChE. In addition to a favorable spatial orientation, this docking pose also revealed strong surface charge interactions which may account for the observed inhibitory effect. While statistical analysis of the dose response and survival ratio suggested that AChE is not the primary mechanism of action for the acute toxicity of K16ApoE, both biochemical evidence and structural analysis have assigned indirect but critical roles for AChE in the overall toxicity mechanism of this peptide carrier.

The Role of Acetylcholine Esterase in Resistance Mechanism of Plutella xylostella to Emamektin Benzoate

One of the resistance mechanism of P. xylostellato emamektin benzoate is target insensitivity which is acetylcholine esterase that responsible for resistance occurrence. The objective of this study was to determine the role of acetylcholinesterase in the resistance mechanism of P. xylostella population to emamektin benzoate. For enzyme activity analysis, larvae homogenate of the third instar of P. xylostella was prepared. The number of insects required for each scour is 1 for each field population. The protein content in P. xylostella homogenate was measured by the Folin-Ciocalteu test. Non-specific esterase activity with an absorption rate was read using ELISA reader tool with λ = 450 nm. The inhibition level of acetylcholinesterase activity by emamectin benzoate in the tested population was 36.84%. The highest inhibition occurs in Puasan (Ngablak) population. The result shows that a α-naphthyl acetate substrate was used so that it was recorded as non-specific esterase activity and did not exhibit esterase activity which specifically describes emamectin benzoate. Non-specific esterase enzyme activity of either α or β-naphthyl acetate substances to benzoic emamectin in the tested population most of the population was still susceptible. On α-naphthyl acetate substrate, the highest absorbance value found in susceptible population to benzoate emamectin (0.773), while the lowest found in Babrik (Ngablak) population (0.083).

Scopolamine-Induced Memory Impairment Is Alleviated by Xanthotoxin: Role of Acetylcholinesterase and Oxidative Stress Processes.

Xanthotoxin, popularly occurring furanocoumarin, which can be found in plants from the Apiaceae family, was isolated from fruits of Pastinaca sativa L. by mean of high-performance countercurrent chromatography, and its effects on the scopolamine-induced cognitive deficits in male Swiss mice using the passive avoidance (PA) test were evaluated. To measure the acquisition of memory processes, xanthotoxin (1, 2.5, 5 mg/kg) was administered 30 min before PA test and scopolamine was administered 10 min after xanthotoxin. To measure the consolidation of memory processes, xanthotoxin (1 and 2.5 mg/kg) was injected immediately after removing the mouse from the apparatus and 10 min after scopolamine was administered. In subchronic experiments, mice were injected with xanthotoxin (1 mg/kg) or saline, 6 days, twice daily. At 24 h after the last injection of the drugs, the hippocampus and the prefrontal cortex were removed for biochemical assays. The results demonstrated that either single (2.5 and 5 mg/kg) or repeatable (1 mg/kg) administration of xanthotoxin significantly increased index of latency (IL) in both acquisition and consolidation of memory processes, showing some procognitive effects. The behavioral tests also showed that an acute (2.5 mg/kg) and subchronic (1 mg/kg) administration of xanthotoxin prevent memory impairment induced by injection of scopolamine (1 mg/kg). Observed effects could be due to the inhibition of acetylcholinesterase activities and amelioration of oxidative stress processes in the hippocampus and the prefrontal cortex. It was suggested that xanthotoxin could show neuroprotective effect in scopolamine-induced cognitive impairment connected to cholinergic neurotransmission and oxidative stress in the brain structures.

Acetylcholinesterase and butyrylcholinesterase in cardiosurgical patients with postoperative delirium

BackgroundPatients in intensive care units (ICU) are often diagnosed with postoperative delirium; the duration of which has a relevant negative impact on various clinical outcomes. Recent research found a potentially important role of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in delirium of critically ill patients on non-surgical ICU or in non-cardiac-surgery patients. We tested the hypothesis that AChE and BChE have an impact on patients after cardiac surgery with postoperative delirium.MethodsAfter obtaining approval from the local ethics committee, this mechanistic study gathered data of all 217 patients included in a randomized controlled trial testing non-pharmacological modifications of care in the cardiac surgical ICU to reduce delirium.Delirium was assessed with the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Nursing Delirium Screening Scale (Nu-DESC) twice a day for the first 3 days after surgery. Further outcome variables were somatic laboratory parameters and variables regarding surgery, anesthesia, and postsurgical recovery. 10 μl venous or arterial blood was drawn and AChE and BChE were determined with ChE check mobile from Securetec.ResultsOf 217 patients, 60 (27.6%) developed postsurgical delirium (POD). Patients with POD were older (p = 0.005), had anemia (p = 0.01), and worse kidney function (p = 0.006). Furthermore, these patients had lower intraoperative cerebral saturation (NIRS) (p < 0.001) and higher intraoperative need of catecholamines (p = 0.03). Delirious patients showed more inflammatory response (p < 0.001). AChE and BChE values were mainly inside the norm. Patients with values outside the norm did not have POD more often than others. Regarding AChE and BChE patients did not differ in having delirium or not (p > 0.10).ConclusionsPostoperative measurement of AChE and BChE did not discern between patients with and without POD. The effect of the cardiac surgical procedure on AChE and BChE remains unclear. Further studies with patients in cardiac surgery are needed to evaluate a possible combination of delirium and the cholinergic transmitter system. There might be possible interactions with AChE/BChE and blood products and the use of cardiopulmonary bypass, which should be investigated more intensively.Trial registrationGerman Clinical Trials Register, DRKS00006217

Role of Acetylcholinesterase in β-Amyloid Aggregation Studied by Accelerated Molecular Dynamics

Mechanisms of Alzheimer’s disease development are still under investigation. It was shown that acetylcholinesterase promotes aggregation of β-amyloid. Accelerated molecular dynamics simulations were performed to investigate molecular mechanisms of this process. Results showed that Aβ is strongly attracted to the surface of acetylcholinesterase and forms stable complexes. It was hypothesized that acetylcholinesterase serves as a nucleation center for propagation of β-amyloid aggregation.

Multiple Mutations on the Second Acetylcholinesterase Gene Associated With Dimethoate Resistance in the Melon Aphid, Aphis gossypii (Hemiptera: Aphididae).

The melon aphid, Aphis gossypii Glover (Hemiptera: Aphididae), is an important cosmopolitan and extremely polyphagous species capable of causing direct and indirect damage to various crops. Insecticide resistance in melon aphids is of particular concern. To determine the basis of resistance, organophosphate (OP)-resistant strains of A. gossypii were obtained by continuous selection with dimethoate in the laboratory, and resistance mechanisms were investigated along with susceptible strains. Three resistant strains LKR-1, LKR-2, and LKR-3 exhibiting 270-, 243-, and 210-fold resistance obtained after 30 generations of selection with dimethoate, respectively, were utilized in this study. The role of acetylcholinesterase (AChE), a target enzyme for OPs and carbamates (CMs), was investigated. AChE enzyme assay revealed that there was no significant change in the activities of AChE in resistant and susceptible strains. However, AChE inhibitory assay showed that 50% of the enzyme activity in resistant strains was inhibited at significantly higher concentration of dimethoate (131.87, 158.65, and 99.29 µmolL(−1)) as compared with susceptible strains (1.75 and 2.01 µmolL(−1)), indicating AChE insensitivity owing to altered AChE. Molecular diagnostic tool polymerase chain reaction-restriction fragment length polymorphism revealed the existence of two consistent non-synonymous point mutations, single-nucleotide polymorphism, viz., A302S (equivalent to A201 in Torpedo californica Ayres) and S431F (equivalent to F331 in T. californica), in the AChE gene Ace2 of resistant strains. Further, cloning and sequencing of a partial fragment of Ace2 (897 bp) gene from susceptible and resistant strains revealed an additional novel mutation G221A in resistant strains, LKR-1 and LKR-2. Susceptible Ace2 genes shared 99.6 and 98.9% identity at the nucleic acid and amino acid levels with resistant ones, respectively. Functional analysis of these point mutations was assessed by in silico docking studies using the modeled wild-type and naturally mutated AChE2. Computational analysis showed that the conformational changes in AChE2 active site due to structural gene substitutions (A302S, S431F, and G221A) significantly reduced the level of ligand (OP-dimethoate, omethoate, and CM-pirimicarb) binding, suggesting that they are potentially associated with resistance development. These results unambiguously suggested that multiple mutations located in the enzyme active site are responsible for AChE insensitivity to dimethoate and are likely the molecular basis for dimethoate resistance in these selected field populations of A. gossypii.

Donepezil prevents RANK-induced bone loss via inhibition of osteoclast differentiation by downregulating acetylcholinesterase.

ObjectiveDonepezil, an inhibitor of acetylcholinesterase (AChE) targeting the brain, is a common medication for Alzheimer's disease. Interestingly, a recent clinical study found that administration of this agent is associated with lower risk of hip fracture independently of falling, suggesting its direct effect on bone tissues as well. AChE has been reported to be involved in osteoblast function, but the role of AChE on osteoclastogenesis still remains unclear. We analyzed the effect of AChE and donepezil on osteoclastogenesis in vivo and in vitro.MethodsCell-based assays were conducted using osteoclasts generated in cultures of murine bone marrow macrophages (BMMs) with receptor activator of nuclear factor-kappa B ligand (RANKL). The effect of donepezil was also determined in vivo using a mouse model of RANKL-induced bone loss.ResultsRecombinant AChE in BMMs cultured with RANKL further promoted RANKL-induced tartrate-resistant acid phosphatase (TRAP)-positive osteoclast differentiation. RANKL also upregulated AChE expression in BMMs. RNA interference-mediated knockdown of AChE significantly inhibited RANKL-induced osteoclast differentiation and suppressed gene expression specific for osteoclasts. AChE upregulated expression of RANK, the receptor of RANKL, in BMMs. Donepezil decreased cathepsin K expression in BMMs and the resorptive function of osteoclasts on dentine slices. Donepezil decreased RANK expression in BMMs, resulting in the inhibition of osteoclast differentiation with downregulation of c-Fos and upregulation of Id2. Moreover, administration of donepezil prevented RANKL-induced bone loss in vivo, which was associated with the inhibition of bone resorption by osteoclasts.ConclusionsAChE promotes osteoclast differentiation in vitro. Donepezil inhibits osteoclast function in vitro and prevents bone loss by suppressing bone resorption in vivo, suggesting the possibility that donepezil reduces fracture risk in patients with Alzheimer's disease.

Role of acetylcholinesterase in lung cancer.

Acetylcholinesterase (AChE) plays a key role in catalytic hydrolysis of cholinergic neurotransmitters. Intensive research has proven the involvement of this protein in novel functions, such as cell adhesion, differentiation, and proliferation. In addition, several recent studies have indicated that acetylcholinesterase is potentially a marker and regulator of apoptosis. Importantly, AChE is also a promising tumor suppressor. In this review, we briefly summarize the involvement of AChE in apoptosis and cancer, focusing on the role of AChE in lung cancer, as well as the therapeutic consideration of AChE for cancer therapy.

Octopus arm regeneration: Role of acetylcholinesterase during morphological modification

The ability to regenerate whole-body structures has been long studied in both vertebrate and invertebrate animal models. Due to this regeneration capability here we propose the use of the Cephalopod Octopus vulgaris as a model of regeneration. We investigated the involvement of acetylcholinesterase (AChE) in the octopus arm regeneration. AChE has been demonstrated to have non-cholinergic functions in various cell types and to be involved in the regulation of cell proliferation, differentiation and apoptosis. In order to follow cell replacement in the octopus arm, we first assessed the expression of specific markers involved in cellular proliferation (AgNOR and PCNA). We showed that the activity of the enzyme AChE is related to the proliferation stage of the arm regenerative process. In the very initial stages of regrowth when most of the proliferation activity was at the level of the ‘blastema’ the cholinesterase activity was very low. AChE activity climbed slowly during the subsequent phase of cellular multiplication and, by the onset of morphogenesis, the activity rose sharply and active myogenesis was observed. AChE activity decreased then till reaching basal level at the time when the process of histogenesis occurred and the reestablishment of all the structures became evident. Interestingly AgNOR and AChE assay showed a similar trend in particular during the stages when the morphogenesis was mostly dependent upon cell proliferation. We suggest that AChE protein may have an important influence in the process of regeneration and that it could be considered as a potential target to promote or regulate the regenerative process.