Cholinesterase Activity Levels Research Articles

Influence of toxoplasmosis on acetylcholinesterase activity, nitric oxide levels and cellular lesion on the brain of mice

The objective of this study was to investigate the activity of acetylcholinesterase (AChE), nitrite/nitrate (NOx) levels, as well as the biomarkers of cellular damage in the brain of mice experimentally infected with Toxoplasma gondii. Sixty mice were divided into two experiments: in experiment I the mice were infected with T. gondii/RH strain, while in experiment II they were infected with T. gondii, strains VEG and ME-49. Our evaluations were carried out on brain homogenized samples, assessing the AChE and glutathione reductase (GR) activities, and NOx, TBARS and AOPP levels in all the infected animals, compared with the control group. In both experiments, I and II, it was observed an increase in the activity of AChE and GR, as well as in the levels of NOx in the brain of infected mice with T. gondii. TBARS levels were increased in mice infected with the three different strains, RH, ME-49, and VEG. AOPP concentration was increased only in mice infected with the RH strain. Animals infected with the strains VEG and ME-49 showed histological lesions, associated with the presence of the parasite in the brain. Therefore, the infection by T. gondii is able to interfere in cholinesterase activity and NO levels, in association with oxidative stress and histological lesion.

Определение дихлофоса, диметоата, хлорпирифоса, фозалона, диазинона и метилпаратиона в крови и моче методом газовой хроматографии с тандемным масс-селективным детектированием

A method was developed for quantification of six organophoshorus pesticides ( OPP ): chlorophos, dimethoate, chloropyrifos, fosalon, diazinon, and methyl parathion. The method allows the target compounds to be determined at a level of 1 ng/ml (1 ppb) in blood and urine samples by gas chromatography with tandem mass-selective detection. Sample preparation procedure includes salting and liquid-liquid extraction with acetonitrile. Method has passed methrological certification (certificate № 222.0320/01.00258/2013), and can be used for monitoring of employees engaged in the production and use of pesticides, as well as those with low levels of cholinesterase activity, or with the corresponding clinical symptoms. The detection limit makes it possible to reveal the intake of OPPs over a period of up to 6 days post exposure at doses equvalent to 1/10−1/50 LD 50 . The method was tested in a toxicological experiment on male rabbits after oral administration of mixture of six OPP’s. Doses of OPP’s was equivalent to 1/10 LD50 and 1/50 LD50. The main toxicokinetic parameters of dimethoate, chloropyrifos, fosalon, diazinon, and methyl parathion was evaluated. Key words : organophosphorus pesticides, GC-MS, blood, urine. (Russian) DOI: http://dx.doi.org/10.15826/analitika.2014.18.3.004 A.I. Ukolov, P.N. Sorokoumov, E.S. Ukolova, E.I. Savel’eva, and A.S. Radilov Research Institute of Hygiene, Occupational Pathology and Human Ecology Federal State Unitary Enterprise, Federal Medical Biological Agency of Russia , Kapitolovo Station, g/p Kuz’molovsky, Vsevolozhsky District, Leningrad Region, Russian Federation

In vivo evaluation of cholinesterase activity, oxidative stress markers, cyto- and genotoxicity of K048 oxime–a promising antidote against organophosphate poisoning.

K048 is a member of K-oximes, a new oxime class that has recently been confirmed effective against poisoning by the nerve agent tabun and several pesticides. The toxicity profile of the K048 oxime has not been fully characterized and its optimal therapeutic dose has not yet been established. Earlier studies report excellent results with K048 in reactivating tabun-phosphorylated AChE and in the therapy of tabun-poisoned mice. It possesses a low acute toxicity and exerts an acceptable toxicity profile on isolated human peripheral blood lymphocytes in vitro. Intraperitoneal administration of K048 in rats resulted in an LD50 of 238.3 mg/kg. In this in vivo study, we investigated cholinesterase (ChE) activity and oxidative stress marker levels (lipid peroxidation and superoxide dismutase activity) in the plasma of exposed rats after administering the compound at 25% of its LD50. Lymphocyte viability was evaluated using an acridine orange/ethidium bromide in situ fluorescent assay. The levels of primary DNA damage in rat white blood cells were measured using the alkaline comet assay. The compound applied at 25% of its LD50 did not significantly affect ChE activity and lipid peroxidation and did not cause significant changes in the SOD activity in plasma. The cytotoxicity profile of K048 in the tested dose was also acceptable, and it did not possess significant DNA-damaging potential. The obtained results are promising for further evaluations of the K048 oxime, which should include tests on a broader concentration range and longer incubation times.

MULBERRY FRUITS EXTRACT MITIGATE VASCULAR DEMENTIA

To date, Vascular Dementia (VaD) is the second most commonly found dementia following Alzheimer�s disease. Though VaD is still increasing its importance, the therapeutic efficacy is still not in satisfaction level. Therefore, the searching for an acceptable cheap and safe neuroprotective agent is in a great demand. Based on the neuroprotective and cognitive enhancing effects in alcohol neurotoxicity of mulberry fruits, we hypothesized that mulberry fruits might attenuate memory impairment and brain damage in vascular dementia. Therefore, this study was set up to determine the effects and possible mechanism of actions of mulberry fruits. Male Wistar rats had been orally given mulberry fruits at doses of 2,10 and 50 mg.kg-1 BW for 7 days before and 21 days after the occlusion of right Middle Cerebral Artery (Rt. MCAO). Rats were evaluated spatial memory using Morris water maze every 7 days after Rt.MCAO throughout 21-day experimental period, then they were sacrificed for determined the density of cholinergic neuron in hippocampus and determine acetyl cholinesterase (AChE) enzyme, a key enzyme indicating Acetylcholine (ACh) turnover in hippocampus and assessment of brain infarction volume The results show that the mulberry fruits extract significantly improved memory performance in Morris water maze test, number of cholinergic neurons and decrease the level of acetyl cholinesterase activity. The mulberry fruit extract is the potential neuroprotective agent and cognitive enhancing fruits. However, further researches are required identify the possible active ingredient and precise underlying mechanism.

Pharmacokinetics and Pharmacodynamics of Chlorpyrifos and 3,5,6-Trichloro-2-pyridinol in Rat Saliva After Chlorpyrifos Administration

Sensors have been developed for noninvasive biomonitoring of the organophosphate pesticide chlorpyrifos (CPF), and previous studies have suggested consistent partitioning of 3,5,6-trichloro-2-pyridinol (TCPy), a metabolite of CPF, into saliva after exposure to TCPy. The objective of this study was to quantitatively evaluate in vivo pharmacokinetics and pharmacodynamics of CPF and TCPy in saliva after CPF administration. Rats were coadministered CPF (0.5-5mg/kg) and pilocarpine (~13 mg/kg) iv. Saliva and blood were collected, and levels of CPF, TCPy, and cholinesterase (ChE) activity were quantified. Experimental results suggest that CPF is rapidly metabolized after iv administration. Formation of TCPy from administered CPF at the low dose (0.5 mg/kg) was slower than from higher CPF doses, potentially due to differences in plasma protein binding to CPF. CPF was measured in saliva only at the first time point sampled (0-15 min), indicating low partitioning and rapid metabolism. After formation, TCPy pharmacokinetics were very similar in blood and saliva. Saliva/blood TCPy concentration ratios were not affected by TCPy concentration in blood, saliva flow rate, or salivary pH and were consistent with previous studies. ChE activity in plasma demonstrated a dose-dependent decrease, and ChE activity in saliva was extremely variable and demonstrated no dose relationship. A physiologically based pharmacokinetic and pharmacodynamic model for CPF was modified and predicted the data reasonably well. It is envisioned that a combination of biomonitoring compounds like TCPy in saliva coupled with computational modeling will form an approach to measure pesticide exposure to susceptible human populations such as agricultural workers.

The Cholinergic System and Inflammation: Common Pathways in Delirium Pathophysiology

To investigate whether delirium is associated with an unbalanced inflammatory response or a dysfunctional interaction between the cholinergic and immune systems. Cohort observational study. General hospital orthopedic ward. One hundred one individuals aged 60 and older with no previous cognitive impairment undergoing elective arthroplasty. Incidence of postoperative delirium, plasma cholinesterase activity (acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE)) and inflammatory mediators (C-reactive protein (CRP), interleukin (IL)-1 beta, tumor necrosis factor alpha, IL-6, IL-8, IL-10) before and after surgery. Thirty-seven participants developed postoperative delirium and had greater production of CRP and proinflammatory to anti-inflammatory ratio after surgery. In participants with delirium, but not in controls, preoperative levels of plasma cholinesterase activity correlated with ΔCRP (AChE: ρ = 0.428, P = .008 and BuChE: ρ = 0.423, P = .009), ΔIL-6 (AChE: ρ = 0.339, P = .04), and ΔP/A ratio (AChE: ρ = 0.346, P = .04). Delirium was associated not only with an unbalanced inflammatory response, but also with a dysfunctional interaction between the cholinergic and immune systems. Comprehensive understanding of the relationship between the cholinergic and immune systems is crucial to developing new insights into delirium pathophysiology and novel therapeutic interventions.

The relationship between cholinesterase inhibition in the chick biventer cervicis muscle and its sensitivity to exogenous acetylcholine.

The effect of physostigmine has been studied on cholinesterase in homogenates of chick biventer cervicis muscles and on the contractile responses of the intact muscles to acetylcholine and carbachol. The concentration of physostigmine required to produce the maximum increase in sensitivity to acetylcholine almost completely inhibited the cholinesterase in muscle homogenates. This concentration of physostigmine had no effect on muscle contractures elicited by carbachol. By taking account of the combined effects of acetylcholine diffusion and enzymic hydrolysis, a quantitative theoretical relationship has been derived between the level of cholinesterase activity in cylindrical muscles and the fractional occupancy of the acetylcholine receptors in these muscles in the presence of different concentrations of exogenous acetylcholine. This theory attributes the thousand-fold increase in sensitivity to exogenous acetylcholine produced by anticholinesterases in chick biventer cervicis muscles largely to an alteration in acetylcholine concentration gradient within the muscle and accounts satisfactorily for the shift in the dose-response curve for acetylcholine which occurs after treatment of the muscles with various concentrations of physostigmine.

Pesticide distributions and population declines of California, USA, alpine frogs, Rana muscosa and Rana sierrae

Atmospherically deposited pesticides from the intensively cultivated Central Valley of California, USA, have been implicated as a cause for population declines of several amphibian species, with the strongest evidence for the frogs Rana muscosa and Rana sierrae at high elevation in the Sierra Nevada mountains. Previous studies on these species have relied on correlations between frog population status and either a metric for amount of upwind pesticide use or limited measurements of pesticide concentrations in the field. The present study tested the hypothesis that pesticide concentrations are negatively correlated with frog population status (i.e., fraction of suitable water bodies occupied within 2 km of a site) by measuring pesticide concentrations in multiple media twice at 28 sites at high elevation in the southern Sierra Nevada. Media represented were air, sediment, and Pseudacris sierra tadpoles. Total cholinesterase (ChE), which has been used as an indicator for organophosphorus and carbamate pesticide exposure, was also measured in P. sierra tadpoles. Results do not support the pesticide-site occupancy hypothesis. Among 46 pesticide compounds analyzed, nine were detected with ≥ 30% frequency, representing both historically and currently used pesticides. In stepwise regressions with a chemical metric and linear distance from the Central Valley as predictor variables, no negative association was found between frog population status and the concentration of any pesticide or tadpole ChE activity level. By contrast, frog population status showed a strong positive relationship with linear distance from the Valley, a pattern that is consistent with a general west-to-east spread across central California of the amphibian disease chytridiomycosis observed by other researchers.

Hematological and biochemical alterations in sprayers occupationally exposed to mixture of pesticides at a mango plantation in Lucknow, India

The aim of this study was to examine the hematological and cholinesterase (ChE) activity levels of pesticide sprayers employed in mango plantations at Lucknow. Fifty-two sprayers from mango plantations who regularly spray mixtures of pesticides including organochlorines (OC), organophosphates (OP), and carbamates were included as exposed group. Twenty residents living close to mango plantations, but not involved in pesticide spraying were taken as controls. Pesticide residues for OC were analyzed in blood by gas chromatography with electron capture detector. There was a significant decrease in acetylcholinesterase and butyrylcholinesterase activities in pesticide sprayers (n = 52) relative to the control group (n = 20). A significant difference in the frequency distribution of hematological variations in red blood cell, white blood cell, monocytes, neutrophils, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelet count was observed. Residues of OC pesticides including α-hexachlorocyclohexane (HCH) and total HCH were found to be significantly higher in the blood of sprayers compared to controls. Hematological variations were quantitatively more frequent among the sprayers with 5 years of pesticide exposure compared to the controls and to subjects with less than 5 years of exposure group. Hematological abnormalities in sprayers were correlated with pesticide exposure as evidenced by lower ChE activity as well as the presence of OC pesticides in blood. The poorly controlled use of pesticides in the plantation appeared to have produced sub-clinical intoxication in the sprayers and indicated the need for training and implementation of proper, safer hygiene practices.

Expression of cholinesterases in human kidney and its variation in renal cell carcinoma types

Despite the aberrant expression of cholinesterases in tumours, the question of their possible contribution to tumorigenesis remains unsolved. The identification in kidney of a cholinergic system has paved the way to functional studies, but details on renal cholinesterases are still lacking. To fill the gap and to determine whether cholinesterases are abnormally expressed in renal tumours, paired pieces of normal kidney and renal cell carcinomas (RCCs) were compared for cholinesterase activity and mRNA levels. In studies with papillary RCC (pRCC), conventional RCC, chromophobe RCC, and renal oncocytoma, acetylcholinesterase activity increased in pRCC (3.92 ± 3.01 mU·mg(-1), P = 0.031) and conventional RCC (2.64 ± 1.49 mU·mg(-1), P = 0.047) with respect to their controls (1.52 ± 0.92 and 1.57 ± 0.44 mU·mg(-1)). Butyrylcholinesterase activity increased in pRCC (5.12 ± 2.61 versus 2.73 ± 1.15 mU·mg(-1), P = 0.031). Glycosylphosphatidylinositol-linked acetylcholinesterase dimers and hydrophilic butyrylcholinesterase tetramers predominated in control and cancerous kidney. Acetylcholinesterase mRNAs with exons E1c and E1e, 3'-alternative T, H and R acetylcholinesterase mRNAs and butyrylcholinesterase mRNA were identified in kidney. The levels of acetylcholinesterase and butyrylcholinesterase mRNAs were nearly 1000-fold lower in human kidney than in colon. Whereas kidney and renal tumours showed comparable levels of acetylcholinesterase mRNA, the content of butyrylcholinesterase mRNA was increased 10-fold in pRCC. The presence of acetylcholinesterase and butyrylcholinesterase mRNAs in kidney supports their synthesis in the organ itself, and the prevalence of glycosylphosphatidylinositol-anchored acetylcholinesterase explains the splicing to acetylcholinesterase-H mRNA. The consequences of butyrylcholinesterase upregulation for pRCC growth are discussed.

Reversal of memory deficits by Coriandrum sativum leaves in mice

Coriandrum sativum L., commonly known as coriander and belonging to the family Apiaceae (Umbelliferae), is cultivated throughout the world for its nutritional value. The present study was undertaken to investigate the effects of fresh Coriandrum sativum leaves (CSL) on cognitive functions, total serum cholesterol levels and brain cholinesterase activity in mice. In this study, CSL (5, 10 and 15% w/w of diet) was fed orally with a specially prepared diet for 45 days consecutively to experimental animals. Elevated plus-maze and passive avoidance apparatus served as the exteroceptive behavioral models for testing memory. Diazepam, scopolamine and ageing-induced amnesia served as the interoceptive behavioral models. CSL (5, 10 and 15% w/w of diet) produced a dose-dependent improvement in memory scores of young as well as aged mice. CSL also reversed successfully the memory deficits induced by scopolamine (0.4 mg kg(-1), i.p.) and diazepam (1 mg kg(-1), i.p.). Interestingly, brain cholinesterase activity and serum total cholesterol levels were considerably reduced by CSL administration in daily diets concomitantly for 45 days. CSL may be a useful remedy in the management of Alzheimer's disease on account of its multifarious effects such as, memory-improving property, cholesterol-lowering property and anticholinesterase activity.

Nerve conduction studies in sprayers occupationally exposed to mixture of pesticides in a mango plantation at Lucknow, North India

In this study, nerve conduction, organochlorine (OC) pesticide residues in blood and cholinesterase activity levels of pesticide sprayers employed in mango plantations at Lucknow, North India, were determined. Fifty-two sprayers from mango plantations who regularly spray mixture of pesticides like organophosphates (OP), OCs, and carbamates were considered as exposed group. Eighteen subjects with similar socio-economic status of exposed group, who do not handle pesticides, were selected as controls. Questionnaire-based interviews related to personal and occupational histories of the study subjects were carried out. Sprayers did not use any personal protective equipment during pesticide handling. The blood-pesticide analyses of sprayers show higher mean values of hexachlorohexane (HCH), γ-HCH, δ-HCH, total HCH, op-DDT compared with the controls. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activites were significantly reduced among sprayers. Risk of motor nerve conduction deficits was observed in sprayers with low AChE activity. Negative correlation of motor and sensory nerve conduction deficits was observed with the duration of exposure and age among sprayers. The study demonstrated that the prolonged exposure to mixture of pesticides, ergonomic factors, decline in cholinesterase activity may lead to nerve conduction dysfunction. The findings suggest the need for controlled use of pesticides in the plantation and indicated the need for training and implementation of hygiene practices like proper usage of personal protective equipments.

Mutations in the insulin pathway affect lipid metabolism, brain function and visual physiology in Drosophila melanogaster

Insulin growth factor signaling is involved in growth and homeostasis in mammals. In Drosophila melanogaster, insulin‐like peptides likewise regulate these processes through the evolutionarily conserved insulin pathway. Here, we studied the effects of mutant conditions for insulin pathway genes. We measured total lipid and carbohydrate levels, brain function as assayed by cholinesterase activity levels (acetylcholine is the main brain neurotransmitter in flies), and retinal function by electrorretinograms (ERGs). We found that mutant flies had generally abnormal high levels of lipids, whereas carbohydrates levels were normal. Several mutants tested (mutations in the insulin receptor, chico (the Drosophila insulin receptor substrate), and protein kinase B) also show electroretinogram defects (reductions in amplitude) and a lower cholinesterase activity in head extracts. In general, metabolic and nervous system alterations correlated in the mutants, suggesting that in flies, as is true in humans, altered metabolism may lead to nervous system impairments. CONACYT 162563; 81864.

Effect of Rhazya stricta Decne on monoamine oxidase and cholinesterase activity and brain biogenic amine levels in rats.

The effect of treatment with the medicinal plant Rhayva stricta Decne, on monoamine oxidase (MAO) and cholinesterase activity, and on the concentration of brain biogenic amines was studied in rats. R. stricta extract, at doses of 0.2 and 0.5 g kg(-1), significantly (P < 0.05-0.01) increased the hepatic and cerebral activity of MAO by 36-127%. The higher doses used (2.0 and 8.0 g kg(-1)) produced smaller (10-26%) and statistically insignificant increases in MAO activity in liver and brain. Cholinesterase activity in blood, liver and brain was not significantly influenced by treatment with R. stricta. The concentrations of the measured biogenic amines (noradrenaline, adrenaline, 5-hydroxytryptamine and dopamine) were significantly lowered in rats treated with R. stricta. The observed increase in MAO activity may be responsible for the lowered biogenic amines levels and may, in part, be responsible for the pharmacological effects of R. stricta extract in rats.

Cholinesterase Activity and mRNA Level of Nicotinic Acetylcholine Receptors (α4 and β2 Subunits) in Blood of Elderly Chinese Diagnosed as Alzheimer's Disease

The aim of the study is to investigate the cholinergic deficit in Alzheimer's disease (AD) and identify candidate blood biomarkers for the diagnosis of the disease. Twenty-nine elderly Chinese diagnosed with AD and 33 age-matched controls were selected. The activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in plasma were detected by a spectrophotometric method, and the mRNA levels of alpha4 and beta2 nicotinic acetylcholine receptor (nAChR) subunits in blood leukocytes were analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR). The results showed that AChE activity in plasma was significantly lower in the AD group than in normal controls, while BuChE activity did not show any differences between AD and controls; mRNA levels of both alpha4 and beta2 nAChR subunits in blood leukocytes were significantly lower in the AD group than in controls. The AChE activity and the mRNA levels of alpha4 and beta2 nAChR subunits in the AD patients were also significantly correlated with cognitive test scores. No differences of AChE in plasma or alpha4 and beta2 nAChR subunits in blood leukocytes were detected between smoking and non-smoking subjects. The results indicated that the decreases in the activity of AChE and in the mRNA levels of nAChR alpha4 and beta2 subunits from the peripheral blood of patients with AD might serve as supplementary indicators for the clinical diagnosis of AD.

Cholinesterase Depression and Its Association with Pesticide Exposure across the Agricultural Season among Latino Farmworkers in North Carolina

BackgroundFarmworkers can be exposed to a wide variety of pesticides. Assessing cholinesterase activity over time can be used to monitor exposure to organophosphorus and carbamate pesticides.ObjectivesThe goal of this study was to document patterns and variation in cholinesterase levels across the agricultural season (May–August) among field-workers, and to explore the association of cholinesterase depression with pesticide exposure across the agricultural season.MethodsDried blood samples collected from 231 migrant farmworkers sampled from camps in eastern North Carolina up to four times across a summer agricultural season were analyzed for cholinesterase activity, and urine samples were analyzed for metabolites of organophosphorus and carbamate pesticides. Reductions of ≥ 15% from an individual’s highest value were identified and considered evidence of meaningful cholinesterase activity depression.ResultsThe average cholinesterase activity levels were lowest in June, with significantly higher mean values in July and August. When adjusted for age, sex, minutes waited to shower, and days worked in the fields, the number of organophosphorus and carbamate pesticides detected in urine predicted reductions in cholinesterase activity.ConclusionsThese data demonstrate that workers are experiencing pesticide exposure. Greater enforcement of existing safety regulations or strengthening of these regulations may be warranted. This study demonstrates that serial measurements of cholinesterase activity across an agricultural season can detect exposure to pesticides among field-workers.

Urinary elimination kinetics of acephate and its metabolite, methamidophos, in urine after acute ingestion

Acephate (AP) is a widely available organophosphorus (OP) insecticide considered to have low mammalian toxicity. In plants and insects, AP is metabolized extensively to methamidophos (MP), a more potent OP insecticide. The limited mammalian metabolism of AP to MP has been studied in laboratory rat models and suggests that initial formation of MP from AP may inhibit further formation. No case reports of human ingestion with urine AP and MP levels have been previously published. A 4-year-old male being evaluated for altered mental status and head trauma was noted to have muscarinic and nicotinic cholinergic signs. Further history suggested possible ingestion of a commercial AP product at an unknown time. Ingestion of AP was confirmed by the presence of urinary AP and MP and severely depressed red blood cell (RBC) cholinesterase and pseudocholinesterase activity levels. The patient initially received atropine in two 0.02 mg/kg IV boluses, then was started on 0.05 mg/kg IV per hour and titrated accordingly to clinical signs of cholinergic toxicity. Pralidoxime was also given at 20 mg/kg IV bolus, followed by an infusion of 10 mg/kg per hour. The patient required mechanical ventilation for 18 days and atropine infusion for 20 days. After a complicated intensive care unit course, he recovered and was discharged after a total of 32 days of hospitalization. Four urine samples collected at different times were analyzed for AP and MP by using high-performance liquid chromatography-atmospheric pressure chemical ionization tandem mass spectrometry. Kinetic calculations were performed by using standard equations. Suspected ingestion was confirmed by the presence of AP and MP in urine. The amount of MP found in urine suggests some limited human metabolism to this more toxic compound. Urinary elimination kinetics of AP demonstrates low metabolic conversion of AP to MP in humans.

Potential of ezetimibe in memory deficits associated with dementia of Alzheimer's type in mice.

Background:High cholesterol levels have been positively correlated with a higher incidence of memory impairment and dementia.Aim:The study was undertaken to investigate the potential of the lipid-lowering drug, ezetimibe, in memory deficits associated with dementia of Alzheimer's (AD) type in mice.Methods:Dementia was induced with chronic administration of a high-fat diet (HFD) or intracebroventricular streptozotocin (ICV STZ, two doses of 3 mg/kg) in separate groups of animals. The memory of the animals was assessed by employing a Morris water maze. Brain thio barbituric acid-reactive species and reduced glutathione levels were measured to assess the total oxidative stress. Brain acetyl cholinesterase (AChE) activity and total serum cholesterol levels were also measured.Results:STZ/HFD produced a significant impairment of memory along with an increase in brain AChE activity and oxidative stress. HFD mice also showed an increase in cholesterol levels. Ezetimibe (10 mg/kg, orally for 15 days) significantly attenuated STZ/HFD-induced memory deficits and biochemical changes. It also prevented HFD-induced rise in the cholesterol level.Conclusions:The memory-restorative effect of ezetimibe can be attributed to its cholesterol-dependent as well as cholesterol-independent effects. The study highlights the potential of ezetimibe in memory dysfunctions associated with dementia of AD.

Valoración de factores de riesgo asociados a los hábitos de manejo y exposición a organofosforados y carbamatos en habitantes y trabajadores de la vereda de Bateas del municipio de Tibacuy, Cundinamarca, Colombia

El uso de plaguicidas en la agricultura ha sido una determinante para el control de plagas. Sin embargo, estos agentes químicos empleados de forma inadecuada, especialmente por parte de los agricultores, se refleja en los efectos nocivos sobre el cuerpo humano; como intoxicación y muerte, especialmente en países subdesarrollados. El presente trabajo tuvo como objetivo valorar los factores de riesgo asociados a los hábitos de manejo y exposición a plaguicidas organofosforados y carbamatos mediante un cuestionario estructurado, la medición de la actividad colinesterásica, y parámetros hematimétricos en trabajadores y habitantes de la vereda de Bateas del Municipio de Tibacuy, Cundinamarca, Colombia, relacionados con la presencia de intoxicación.Se encontró que los factores de riesgo relacionados más sobresalientes fueron el uso inadecuado de elementos de protección personal y la falta de evacuación previa a la fumigación. El 100% de la población participante en el estudio tuvo niveles bajos de actividad de colinesterasa; entre 0,056 pH/hora y 0,445 pH/hora en los hombres y 0,052 pH/hora a 0,264 pH/hora en las mujeres, con un valor medio de 0,148 pH/hora (valor de referencia: hombres de 0,855 a 0,881 pH/hora, mujeres de 0,836 a 0,859 pH/hora). Los estudios poblacionales epidemiológicos son importantes, porque permiten valorar e identificar cualquier fenómeno que sea un riesgo para el bienestar de una población.

Antiamnesic potential of Murraya koenigii leaves

Murraya koenigii leaves commonly known as curry patta are added routinely to Indian gravy and vegetarian dishes as a favorite condiment. The effects of Murraya koenigii leaves (MKL) on cognitive functions, total serum cholesterol level and brain cholinesterase activity in young and aged mice fed orally with a diet containing 2%, 4% and 8% w/w of MKL for 30 days consecutively, were investigated. The memory scores were measured using various exteroceptive and interoceptive behavioral models. The MKL diets produced a significant dose-dependent improvement in the memory scores of young and aged mice and significantly reduced the amnesia induced by scopolamine (0.4 mg/kg, i.p.) and diazepam (1 mg/kg, i.p.). Also, brain cholinesterase activity and total cholesterol levels were reduced by the MKL diets. The underlying mechanism of action for the observed nootropic effect may be attributed to pro-cholinergic activity and a cholesterol lowering property. Therefore, it would be worthwhile to investigate specifically the therapeutic potential of MKL in the management of Alzheimer patients.