Erythrocyte Acetylcholinesterase Research Articles

Acetylcholinesterase purification from human erythrocytes using magnetic nanoparticles containing procainamide

This work presents a magnetic purification method of human erythrocyte Acetylcholinesterase (EC 3.1.1.7; AChE) based on affinity binding to procainamide (Proca) as ligand. Acetylcholinesterase is an acetylcholine-regulating enzyme found in different areas of the body and associated with various neurological disorders, such as Parkinson, Alzheymer and Amyotrophic Lateral Sclerosis. AChE from human erythrocyte purification has been attempted in recent years with low degree of purity. Here, magnetic nanoparticles (MNP) were synthesized and coated with polyaniline (PANI) and procainamide (PROCA) was covalently linked to the PANI. The extracted human erythrocyte AChE formed a complex with the MNP@PANI-PROCA and an external magnet separated it from the undesired proteins. Finally, the enzyme was collected by increasing the ionic strength. Experimental Box-Behnken design was developed to optimize this process of human erythrocyte AChE purification protocol. The enzyme was purified in all fifteen experiments. However, the best AChE purification result was achieved, about 2000 times purified, when 100 mg of MNP@PANI-PROCA was incubated for one hour with 4 ml hemolysate extract. The SDS-PAGE of this preparation presented a molecular weight of approximately 70 kDa, corroborating with few previous studies of AChE from erythrocyte purification.

Acute poisoning by chlorpyrifos differentially impacts survival and cardiorespiratory function in normotensive and hypertensive rats

Hypertension is the most important and well-known risk factor for cardiovascular disease (CVD). Recently, acute organophosphate (OP) poisoning has also been pointed as a CVD risk factor. Despite this evidence, no studies have contrasted the acute toxicosis and cardiovascular (CV) effects of OP poisoning under conditions of normotension and hypertension. In this work, adult male normotensive Wistar and Spontaneously Hypertensive rats (SHR) were intraperitoneally injected with saline or chlorpyrifos (CPF), an OP compound, monitored for acute toxicosis signs and 24-h survival. After poisoning, blood pressure, heart rate and ventilation were recorded, the Bezold-Jarisch Reflex (BJR), the Chemoreflex (CR) were chemically activated, as well as the cardiac autonomic tone (AUT) was assessed. Erythrocyte and brainstem acetylcholinesterase and plasmatic butyrylcholinesterase (BuChE) activities were measured as well as lipid peroxidation, advanced oxidation protein products (AOPP), nitrite/nitrate levels, expression of catalase, TNFα and angiotensin-I converting enzyme (ACE-1) within the brainstem. CPF induced a much more pronounced acute toxicosis and 33 % lethality in SHR. CPF poisoning impaired ventilation in SHR, the BJR reflex responses in Wistar rats, and the chemoreflex tachypneic response in both strains. CPF inhibited activity of cholinesterases in both strains, increased AOPP and nitrite/nitrate levels and expression of TNFα and ACE-1 in the brainstem of Wistar rats. Interestingly, SHR presented a reduced intrinsic BuChE activity, an important bioscavenger. Our findings show that, CPF at sublethal doses in normotensive rats lead to lethality and much more pronounced acute toxicity signs in the SHR. We also showed that cardiorespiratory reflexes were differentially impacted after CPF poisoning in both strains and that the cardiorespiratory disfunction seems to be associated with interference in cholinergic transmission, oxidative stress and inflammation. These results points to an increased susceptibility to acute toxicosis in hypertension, which may impose a significant risk to vulnerable populations.

Acetylcholinesterase Inhibition in Rats and Humans Following Acute Fenitrothion Exposure Predicted by Physiologically Based Kinetic Modeling-Facilitated Quantitative In Vitro to In Vivo Extrapolation.

Worldwide use of organophosphate pesticides as agricultural chemicals aims to maintain a stable food supply, while their toxicity remains a major public health concern. A common mechanism of acute neurotoxicity following organophosphate pesticide exposure is the inhibition of acetylcholinesterase (AChE). To support Next Generation Risk Assessment for public health upon acute neurotoxicity induced by organophosphate pesticides, physiologically based kinetic (PBK) modeling-facilitated quantitative in vitro to in vivo extrapolation (QIVIVE) approach was employed in this study, with fenitrothion (FNT) as an exemplary organophosphate pesticide. Rat and human PBK models were parametrized with data derived from in silico predictions and in vitro incubations. Then, PBK model-based QIVIVE was performed to convert species-specific concentration-dependent AChE inhibition obtained from in vitro blood assays to corresponding in vivo dose-response curves, from which points of departure (PODs) were derived. The obtained values for rats and humans were comparable with reported no-observed-adverse-effect levels (NOAELs). Humans were found to be more susceptible than rats toward erythrocyte AChE inhibition induced by acute FNT exposure due to interspecies differences in toxicokinetics and toxicodynamics. The described approach adequately predicts toxicokinetics and acute toxicity of FNT, providing a proof-of-principle for applying this approach in a 3R-based chemical risk assessment paradigm.

Organofosfat Zehirlenmesi Olan Kritik Hastalarda Plazmaferez ve Standart Tedavinin Serum Psödokolinesteraz ve Eritrosit Asetilkolinesteraz Düzeyleri Üzerindeki Etkisinin Standart Tedavi ile Karşılaştırılması: Randomize Kontrollü, Açık Etiketli, Klinik Çalışma

Objective: Organophosphates are the insecticides commonly used worldwide. Inadequate treatment in organophosphates poisoning increases morbidity, and mortality. Purpose of the work was to determine the effect of standard treatment alone versus standard treatment plus plasmapheresis on the levels of serum pseudo-cholinesterase, and erythrocyte acetyl cholinesterase in severe patients with organophosphates poisoning. Material and Method: This research is a prospective study. Patients diagnosed with organophosphates poisoning were included in the work. The patients were divided into two groups as the intervention group, and the standard group. The intervention group, plasmapheresis was performed in addition to the standard treatment. Results: The research was conducted with forty cases. (Intervention group n:21, standard group n:19). Serum pseudo-cholinesterase values were 482.5 u/L at baseline, 3723 u/L after plasmapheresis. Erythrocyte acetyl cholinesterase values were 1.91 u/mL on admission, 2.53 u/mL after plasmapheresis. Erythrocyte acetyl cholinesterase and serum pseudo-cholinesterase values were compared between the two groups daily from the admission of patients to intensive care units during the first 5 days, and on the last day in the intensive care units. There was no statistical difference between two groups (p> 0.05), except for the second day. It was observed that there was a statistically significant difference between the pseudo-cholinesterase values in the second day comparison of both groups (p=0.028). Conclusion: In conclusion, plasmapheresis treatment may contribute positively to pseudo-cholinesterase level. This treatment may have provided additional time for the organophosphates to be eliminated from the body. Although acetyl cholinesterase reactivation is achieved with oxime treatment, the clinical effect of this treatment is not clear.

Cholinesterases as hemolytic and Inflammatory markers in Beta thalassemia trait patients

Beta thalassemia trait (BTT) is one of the most common monogenic disorders characterized by increased alpha and gamma chains with concomitant decrease in beta chains. These patients are clinically asymptomatic with mild anemia, subclinical inflammation and endothelial dysfunction. This study was undertaken to determine the role of cholinesterases in BTT. The study population included 30 BTT patients and 30 age and sex matched controls. Patients were labelled as BTT only if they had Hb A2 >3.5 and/ HbF>2 by variant analysis using cation HPLC. Percentage hemolysis, erythrocyte acetyl cholinesterase (AChE), plasma butyryl cholinesterase (BChE) and globulins were estimated by spectrophotometric methods. Intracellular adhesion molecule (ICAM-1) was evaluated by ELISA. Percentage hemolysis was significantly high in BTT patients. Both the cholinesterases were lower in BTT patients compared to controls. Decrease in BChE was statistically significant (p< 0.0001). An apparent increase in plasma ICAM-1 was observed in BTT patients compared to the normal group. The increase in plasma globulins was statistically significant in BTT (p<0.0001). AChE and HbA1C showed significant negative correlation with percentage hemolysis. Further, acetylcholinesterases showed a statistically significant negative correlation with ICAM-1. A negative correlation between globulins and cholinesterases in BTT, highlights the involvement of cholinesterases in inflammation.Based on our findings, we conclude that cholinesterases play a key role in inflammation and can be considered as biomarkers of hemolysis in BTT.

The relationship between the cholinergic mechanism of toxicity and oxidative stress in rats during subacute diazinon poisoning

Diazinon is an organophosphate pesticide (OP) that has significant potential for accidental and intentional poisoning of wildlife, domestic animals and humans.The aim of the study is to investigate the correlation between cholinesterase activity and oxidative stress parameters in liver and diaphragm by continuous monitoring as a function of time during prolonged use of diazinon.Wistar rats were treated orally with diazinon (55 mg/kg/day): 7, 14, 21 and 28 days. At the end of each period, blood, liver and diaphragm were collected to examine cholinesterase activity and enzymatic/non-enzymatic oxidative stress parameters: superoxide dismutase 1 (SOD1), catalase (CAT), thiobarbituric acid substances (TBARS), protein carbonyl groups.In all four time periods, there was a significant change in acetylcholinesterase (AChE) in erythrocytes and butyrylcholinesterase (BuChE) in blood plasma, CAT in liver and diaphragm and SOD1 in diaphragm. Parameters significantly altered during the cholinergic crisis included: cholinesterases and TBARS in liver and diaphragm and partially SOD1 in liver. Protein carbonyl groups in liver and diaphragm were significantly altered outside the cholinergic crisis. In the liver, there was a very strong negative correlation between BuChE and TBARS in all four time periods and BuChE and CAT on day 7. In the diaphragm, a very strong negative correlation was found between AChE and TBARS at days 7 and 14, and a very strong positive correlation between AChE and SOD1 at days 14, 21 and 28.A better understanding of the relationship between cholinergic overstimulation and oxidative stress may help to better assess health status in prolonged OPs intoxication.

Arylboronic acids as safe and specific human butyrylcholinesterase inhibitors

The drug treatment of Alzheimer's disease (AD) remains a significant scientific challenge, necessitating a continual search for new drug candidates. In this context, we present here, for the first time, new oxime-arylboronic acid hybrids (L1-L6) as potential anti-AD agents. These hybrids were synthesized and evaluated for their inhibitory capabilities on the activity of non-human cholinesterases [Electrophorus electricus Acetylcholinesterase (EeAChE) and Equine Butyrylcholinesterase (EqBChE)] as well as human cholinesterases [erythrocyte Acetylcholinesterase (hAChE) and plasma Butyrylcholinesterase (hBChE)]. We also assessed the safety of these compounds in a microglia cell line and analyzed the compound-enzyme interactions using molecular docking and molecular dynamics simulations. All compounds were found to be safe for the tests conducted. None of them exhibited significant inhibitory activity against hAChE or EeAChE. However, L1-L5 demonstrated inhibition of EqBChE and hBChE, with L3 being the most potent inhibitor of hBChE (IC50 = 6.41 ± 0.62 µM) and EqBChE (IC50 = 81.28 ± 4.01 µM). Additionally, L2, L3, and L5 showed 8–15 times higher potency as inhibitors of hBChE compared to EqBChE. These findings indicate that the hybrid oxime-arylboronic acids act as specific inhibitors of BChE, with a notable selectivity for hBChE, making them promising structures for the development of more potent and selective hBChE inhibitors.

Risk factors, erythrocyte acetylcholinesterase inhibition, and self-reported symptoms of pesticide intoxication among farmers in Thailand: A cross-sectional study.

Organophosphate and carbamate pesticides are widely used, and their adverse health effects remain a serious problem. This investigation aimed to describe risk factors, erythrocyte acetylcholinesterase (AChE) inhibition, and self-reported symptoms and to derive an association between influence factors and erythrocyte AChE inhibition among farmers in Thailand. A cross-sectional study was conducted on 71 farmers from August to October 2022. General characteristics and pesticide exposure factors were elicited via a questionnaire-based interview. The erythrocyte AChE inhibition was assessed using the EQM Test-mate Cholinesterase (Model 400) instrument. Data were presented descriptively and analyzed statistically using Chi-square and binary logistic regression. Most farmers were over 50 years old and had an abnormal body mass index (BMI) without alcohol consumption and smoking. Aprons (18.31%) and protective eyewear (12.68%) as personal protective equipment (PPE) were found to be used less often. The level of hemoglobin-adjusted erythrocyte AChE (Q) was considered normal when it was 59.15% and abnormal when it was 40.85%. Self-reported symptoms were confirmed to be associated with lower erythrocyte AChE levels. The Chi-square analysis showed that shortness of breath, irritation, headache, dizziness, sleep fragmentation, and memory problems were significantly associated with erythrocyte AChE (p < 0.05). The bivariate analysis revealed that farmers who consumed alcohol while using pesticides (mixing, loading, and spraying) (OR=35.821, 95% CI=4.591-279.490), who did not wear a mask while using pesticides (OR=11.898, 95% CI=1.061-133.440), and who did not wear boots while using pesticides (OR=0.166, 95% CI=0.031-0.890) had an increased likelihood of having a severe inhibition of erythrocyte AChE. These findings suggest that the promotion of risk prevention practices must be imposed on appropriate pesticide handling and PPE use among farmers.

Biochemical role of zinc in vivax malaria

Introduction and Aim: Zinc is a micronutrient that has a significant immune modulatory function, its deficiency is known to increase the risk of plasmodium infection in humans Although inflammatory processes contribute to the elimination of plasmodium, persistent inflammation is the underlying cause of malaria pathology. Cholinesterases are carboxypeptidases that are zinc dependent and are the indicators of low-grade inflammation. Plasma butyryl cholinesterase, is a biomarker of dietary status of zinc. Matrix metalloproteinases (MMP) are endopeptidases that contain zinc which take part in inflammatory reactions. They participate in remodeling of extracellular matrix and aid tissue repair. The current investigation aims to study the association of these metalloproteins with zinc in patients with vivax malaria. Materials and methods: Plasma zinc, butyrylcholinesterase (BChE) and erythrocyte acetylcholinesterase (AChE) were estimated spectrophotometrically in 100 vivax malaria patients and 50 healthy subjects. MMP9 was determined using ELISA. Results: Plasma zinc was markedly lower in malaria patients compared to healthy controls (p&lt;0.05). Both BChE and AChE decreased significantly in malaria (p&lt;0.00) compared to healthy subjects. There was an elevation of MMP9 in malaria, although the increase was statistically insignificant. Cholinesterases correlated positively with zinc in controls and malaria. MMP9 showed a significant positive correlation with zinc in malaria patients (r=0.405, p=0.05). Conclusion: The study highlights the role of zinc in the pathology of malaria as it is essential for the maintenance of several enzyme activities. Further, prompt administration of micronutrients like zinc may reduce the inflammation related morbidity in malaria.

Inhibitory Action of Omega-3 and Omega-6 Fatty Acids Alpha-Linolenic, Arachidonic and Linoleic acid on Human Erythrocyte Acetylcholinesterase.

Acetylcholinesterase (AChE, E.C. 3.1.1.7) termed as the true cholinesterase functions to end cholinergic transmission at synapses. Due to its diverse expression in non-neural tissues such as erythrocytes and bones along with its various molecular forms, researchers seek a non-classical role for this protein. Here, the inhibitory action of unsaturated 18 carbon fatty acids linoleic acid and alpha-linolenic acid and 20 carbon fatty acid arachidonic acid on AChE were investigated. Enzyme activity was measured in kinetic assay method according to Ellman assay utilizing acetylthiocholine. Analysis of the activity data revealed that among the fatty acids examined the IC50 values differed according to the length of the fatty acid and the number of the double bonds. Arachidonic acid, a 20-carbon fatty acid with 4 unsaturated bonds (20:4 n-6, cis 5,8,11,14) displayed an IC50 value of 2.78 µM and Ki value of 396.35 µM. Linoleic acid, an essential 18-carbon fatty acid (18:2 n-6, cis 9,12) had an IC50 value of 7.95 µM and Ki value of 8027.55 µM. The IC50 value of alpha-linolenic acid, 18-carbon fatty acid (18:3 n-3, cis-9,12,15) was found as 179.11 µM. Analysis of the data fit the inhibition mechanism for linoleic, alpha-linolenic and arachidonic acid as mixed-type; non-competitive. Molecular docking complied with these results yielding the best score for arachidonic acid. The alkenyl chain of the fatty acids predictably reached to the catalytic site while the carboxylate strongly interacted with the peripheric anionic site.

Transdermal Delivery of 2-PAM as a Tool to Increase the Effectiveness of Traditional Treatment of Organophosphate Poisoning

For the first time, the efficacy of post-exposure treatment of organophosphate (OP) poisoning was increased by transdermal delivery of acetylcholinesterase (AChE) reactivator pyridine-2-aldoxime methochloride (2-PAM) as a preventive countermeasure. By selecting the optimal ratio of components, classical transfersomes (based on soybean phosphatidylcholine and Tween 20) and modified transfersomes (based on soybean phosphatidylcholine, Tween 20 and pyrrolidinium cationic surfactants with different hydrocarbon tail lengths) were obtained for 2-PAM encapsulation. Transfersomes modified with tetradecylpyrrolidinium bromide showed the best results in encapsulation efficiency and sustained release of 2-PAM from vesicles. Using Franz cells, it was found that the incorporation of surfactants into PC liposomes results in a more prolonged release of 2-PAM through the rat skin. Transfersomes containing 2-PAM, after exhaustive physical and chemical characterization, were embedded in a gel based on Carbopol® 940. A significantly high degree of erythrocyte AChE reactivation (23 ± 7%) was shown for 2-PAM in unmodified transfersomes in vivo. Preliminary transdermal administration of 2-PAM 24 h before emergency post-exposure treatment of OP poisoning leads to an increase in the survival rate of rats from 55% to 90%.

Organochlorine and organophosphorus pesticides may induce brain cancer through oxidative stress.

In this study, oxidative stress was investigated as the possible mechanism of action of organochlorine pesticides (OCPs) and organophosphorus pesticides (OPPs) in primary brain tumors (PBT). The levels of seven OCP residues and enzymatic antioxidant biomarkers including erythrocyte acetylcholinesterase (AChE), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and paraoxonase-1 (PON-1) along with non-enzymatic oxidative biomarkers including malondialdehyde (MDA), protein carbonyl (PC), total antioxidant capacity (TAC), and nitric oxide (NO) were measured in blood samples of 73 patients with PBT and 104 healthy controls. A significant association was found between farming activities and PBT (55% of patients were engaged in farming activities while 45% had no farming experience). The mean levels of β-HCH, γ-HCH, 2,4 DDE, 4,4 DDE, 4,4 DDT, MDA, PC, NO, SOD, CAT, and GPx were significantly higher in PBT patients, whereas the levels of TAC, PON-1, and AChE were significantly lower in these patients. Regression analysis showed that PBT was correlated with β-HCH, γ-HCH, 2,4 DDE, 4,4 DDE, and 4,4 DDT. Based on these results, it can be concluded that OCPs and OPPs may play a role in PBT development through the formation of reactive oxygen species (ROS) and promoting oxidative stress.

Non-covalent acetylcholinesterase inhibitors: In vitro screening and molecular modeling for novel selective insecticides

Insecticides represent the most crucial element in the integrated management approach to malaria and other vector-borne diseases. The evolution of insect resistance to long-used substances and the toxicity of organophosphates (OPs) and carbamates are the main factors contributing to the development of new, environmentally safe pesticides. In our work, fourteen compounds of 7-methoxytacrine-tacrine heterodimers were tested for their insecticidal effect. Compounds were evaluated in vitro on insect acetylcholinesterase from Anopheles gambiae (AgAChE) and Musca domestica (MdAChE). The evaluation was executed in parallel with testing on human erythrocyte acetylcholinesterase (HssAChE) and human butyrylcholinesterase (HssBChE) using a modified Ellman's method. Compound efficacy was determined as IC50 values for the respective enzymes and selectivity indexes were expressed to compare the interspecies selectivity. Docking studies were performed to predict the binding modes of selected compounds. K1328 and K1329 provided high HssAChE/AgAChE selectivity outperforming standard pesticides (carbofuran and bendiocarb), and thus can be considered as suitable lead structure for novel anticholinesterase insecticides.

Post-VX exposure treatment of rats with engineered phosphotriesterases

The biologically stable and highly toxic organophosphorus nerve agent (OP) VX poses a major health threat. Standard medical therapy, consisting of reactivators and competitive muscarinic receptor antagonists, is insufficient. Recently, two engineered mutants of the Brevundimonas diminuta phosphotriesterase (PTE) with enhanced catalytic efficiency (kcat/KM = 21 to 38 × 106 M−1 min−1) towards VX and a preferential hydrolysis of the more toxic P(−) enantiomer were described: PTE-C23(R152E)-PAS(100)-10-2-C3(I106A/C59V/C227V/E71K)-PAS(200) (PTE-2), a single-chain bispecific enzyme with a PAS linker and tag having enlarged substrate spectrum, and 10-2-C3(C59V/C227V)-PAS(200) (PTE-3), a stabilized homodimeric enzyme with a double PASylation tag (PAS-tag) to reduce plasma clearance. To assess in vivo efficacy, these engineered enzymes were tested in an anesthetized rat model post-VX exposure (~ 2LD50) in comparison with the recombinant wild-type PTE (PTE-1), dosed at 1.0 mg kg−1 i.v.: PTE-2 dosed at 1.3 mg kg−1 i.v. (PTE-2.1) and 2.6 mg kg−1 i.v. (PTE-2.2) and PTE-3 at 1.4 mg kg−1 i.v. Injection of the mutants PTE-2.2 and PTE-3, 5 min after s.c. VX exposure, ensured survival and prevented severe signs of a cholinergic crisis. Inhibition of erythrocyte acetylcholinesterase (AChE) could not be prevented. However, medulla oblongata and diaphragm AChE activity was partially preserved. All animals treated with the wild-type enzyme, PTE-1, showed severe cholinergic signs and died during the observation period of 180 min. PTE-2.1 resulted in the survival of all animals, yet accompanied by severe signs of OP poisoning. This study demonstrates for the first time efficient detoxification in vivo achieved with low doses of heterodimeric PTE-2 as well as PTE-3 and indicates the suitability of these engineered enzymes for the development of highly effective catalytic scavengers directed against VX.

Pesticide-induced changes in cholinesterase activity and chronic kidney disease of unknown etiology among farmers in Nakhon Ratchasima, Thailand

Chronic kidney disease of unknown etiology (CKDu) has emerged agricultural population. This study aimed to obtain a prevalence of cholinesterase activity and CKDu, and evaluate factors associated with organophosphate (OP) and carbamate (CA) poisoning and CKDu among farmers in Nakhon Ratchasima province, Thailand. A cross-sectional study was conducted among 58 farmers, with data collected using a structured questionnaire. Blood and urine samples were collected for analysis of erythrocyte acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), serum creatinine (SCr), and urinary creatinine (UCr). Farmers who had CKD without diabetes, hypertension, proteinurea, and other traditional causes were classified as CKDu. The average age (± SD) was 49.22(± 6.87) years. The prevalence of abnormal AChE and BuChE activity levels were 55.17% and 46.55%, respectively. In kidney function, the prevalence of abnormal UCr was 17.24% and CKDu was 24.14%. In adjusted model, the type of pesticide sprayer and personal protective equipment used were significantly associated with CKDu (bivariate analysis, p < 0.05). Using multivariate analysis, OP and CA poisoning were significantly associated with a 4.703-fold higher risk of CKDu (95% CI = 1.020-21.686). Farmers who applied OP and CA pesticides had decreased kidney function. These findings might be beneficial in reducing the adverse effects pesticide exposure and CKDu prevention.

Pesticide exposure and related health problems among farmworkers' children: a case-control study in southeast Iran.

Pesticides are potentially hazardous chemicals that can cause injury to human health and the environment. The purpose of this study was to evaluate organophosphate pesticides (OPPs) and organochlorine pesticides (OCPs) exposure in farmworkers' children aged 6 to 11years in Jiroft city in southeastern Iran. One hundred twenty farmworkers' children as case and 53 non-farmworkers' children aged 6 to 11years as control were selected and the serum levels of OCPs were measured by using gas chromatography in all participants. In addition, erythrocyte acetylcholinesterase (AChE) and arylesterase activity of paraoxonase-1 (PON-1) were measured to evaluate OPPs effects. Catalase (CAT), superoxide dismutase3 (SOD3), glutathione peroxidase (GPx3) activities, and the levels of serum malondialdehyde (MDA), total antioxidant capacity (TAC), nitric oxide (NO), and protein carbonyl (PC) were measured to investigate OCPs and OPPs effects on oxidative stress (OS). The serum levels of beta-HCH, 4,4 DDE, and 4,4 DDT in the case group were significantly higher than the control group. In addition, in the case group, AChE, PON-1, CAT, SOD3, and GPx3 activities and the levels TAC were significantly lower, while MDA, PC, and NO levels were significantly higher than the control group. OCPs as illegal pesticides are present in southeast Iran and children are exposed to OCPs and OPPs in the studied area. In addition, higher serum levels of pesticides may be a major contributor in OS development, as a cause of many diseases.

Investigation of Serum and Leukocyte Ascorbic Acid, Plasma and Intra-Erythrocyte Cholinesterase Levels in Obese Persons

Obesity is a complicated disease, including excessive amounts of body fat. Obesity is not just an aesthetic problem. It is also a medical issue that increases your risk of other diseases and health conditions, like heart disease, diabetes, and certain cancers. Ascorbic acid (A.A.) produced analog enhancing effects in superoxide generation, DNA strand cutting, and cytotoxicity. In leukocytes, toxicity due to mitochondrial permeability was seen in cells exposed to A.A./peroxynitrite, and these responses were determined to occur independently of Ca2 +. Plasma cholinesterase and erythrocyte acetylcholinesterase activities have a long history of use, both in monitoring workers at risk for organophosphorus pesticide (O.P.) exposure and investigating accidental exposures to O.P.s. Due to the wide variation between individuals, it is necessary to establish unexposed, essential enzyme activities for correct interpretation. Forty-four females and 32 males with a mean age of 40 ± 11.4 years were included in our study. In our study, those with a BMI of 18-24 were considered as control or non-obese (group 1), those between 25 and 30 as obese (group 2), and those between 31 and 42 as extremely obese (group 3). With a moderate standard deviation of 70 and 20 % erosion rate, 76 subjects were determined for 93 % power at the 5 % level of significance. Baseline comparisons among treatment sequences were analyzed using a chi-square test for categorical variables and an unpaired t-test for continuous variables. Mean and standard deviation values were assessed using the SPSS package program, and a statistically significant difference was determined at p-level below 0.05 value. As a result; Although the increase in PCE levels and the decrease in ECE, PTA, and P.A. levels were significantly different. The difference between group 2 and group 3 revealed the importance of these differences between obese and non-obese patients. It has been determined that as obesity increases, the risk of vitamin deficiency also increases.

Caracterização de indivíduos com câncer, residentes no meio rural, práticas no uso de agrotóxicos e níveis de acetilcolinesterase eritrocitárias

O objetivo do presente estudo foi caracterizar indivíduos do meio rural, diagnosticados com câncer, quanto às práticas no uso de agrotóxicos, sintomas físicos, emocionais, de intoxicação e níveis de acetilcolinesterase eritrocitária. Trata-se de pesquisa transversal, quantitativa, descritiva, em hospital geral, com 92 pacientes oncológicos e agricultores. O projeto foi aprovado pelo CEP sob o número 2.626.873. Instrumento de coleta de dados com variáveis sociodemográficas, práticas no manuseio de agrotóxicos e mensuração da acetilcolinesterase eritrocitária. A análise dos dados com programa Statistical Package for Social Science, estatística descritiva e analítica. Os resultados demonstraram que a maioria do sexo masculino, idoso, baixa escolaridade. Predominam pequenas propriedades rurais, cultivo de hortifrutigranjeiros. 63% expostos ocupacionalmente a agrotóxicos; para proteção, 56,8% usam botas, “sempre”. Orientação técnica insuficiente. Baixa frequência de intoxicação. Menor média de acetilcolinesterase eritrocitária no grupo exposto a agrotóxicos ativo, estatisticamente significativa. Evidenciou-se o predomínio de agricultura familiar, com produção de hortifrutigranjeiros e uso de equipamentos que favorecem o contato direto com agrotóxicos, inclusive uso inadequado de EPIs. Lacunas quanto ao uso seguro destes produtos, provavelmente relacionada à escolaridade, os tornam suscetíveis a agravos da exposição direta e indireta. Mensuração da acetilcolinesterase eritrocitária mostrou valores médios normais e requer exames complementares e monitoramento contínuo. Resultados remetem à ações e intervenções educacionais com vistas à prevenção de agravos e redução dos índices crescentes de câncer nesta população.

Inhibition Kinetics of 16 Organophosphorus Pesticides or Their Active Metabolites on Erythrocyte Acetylcholinesterase From Humans and Rats.

Inhibition kinetics assays were conducted with 16 commercial organophosphate (OP) pesticides or their metabolites on acetylcholinesterase (AChE) in erythrocyte "ghost" preparations from 18 individual humans (both sexes; adults, juveniles, and cord blood samples; mixed races/ethnicities) and pooled samples from adult rats (both sexes). A well-established spectrophotometric assay using acetylthiocholine as substrate and a chromogen was employed. The kinetic parameters bimolecular rate constant (ki), dissociation constant (KI), and phosphorylation constant (kp) were calculated for each compound. As expected, a wide range of potencies were displayed among the tested compounds. Statistical analysis of the resultant data indicated no differences in sex, age, or race/ethnicity among the human samples that are unexpected based on chance (4.2% statistically significant out of 48 parameters calculated) and no differences between the sexes in rats. The bimolecular rate constants for 10 of the compounds were not statistically different between rats and humans. The data indicate that, consistent with the high level of conservation of AChE among species and the fact that AChE at different locations within a species arises from the same gene, the inhibition kinetic parameters calculated from rat erythrocyte ghost preparations should be useful in estimating potencies of OP compounds on target AChE in humans. Additionally, the data indicate that differences in sensitivities among individual humans were not apparent.

Acetylcholinesterase activity and thyroid hormone levels in Ecuadorian adolescents living in agricultural settings where organophosphate pesticides are used.

Organophosphates are frequently applied insecticides that inhibit acetylcholinesterase (AChE) activity resulting in cholinergic overstimulation. Limited evidence suggests that organophosphates may alter thyroid hormone levels, although studies have yielded inconsistent findings. We aimed to test the associations between AChE activity, a physiological marker of organophosphate exposure, and thyroid function in adolescents. We included information of 80 adolescent participants (ages 12-17y in 2016, 53% male) growing up in agricultural settings in Ecuador. We measured fingerstick erythrocytic AChE activity and hemoglobin concentration, and concurrent serum thyroid stimulating hormone (TSH) and free-T4 (fT4) concentrations. General linear models were used to test associations which adjusted for demographic and anthropometric variables. TSH associations were further adjusted for fT4. The mean (SD) AChE, TSH and fT4 levels were 3.77 U/mL (0.55), 2.82 μIU/ml (1.49) and 1.11ng/dl (0.13), respectively. Lower AChE activity, indicating greater organophosphate exposure, was marginally associated with greater fT4 concentrations (difference per SD decrease in AChE activity (β)=0.03ng/dL, [90% CI: 0.00, 0.06]) but not with TSH (β=-0.01 μIU/ml, [-0.38, 0.36]). Gender modified the AChE-TSH association (p=0.03). In girls, lower AChE activity was associated with higher fT4 levels (β=0.05ng/dL [0.01, 0.10]) and lower TSH concentrations (β=-0.51 μIU/ml, [-1.00, -0.023]). No associations were observed in boys. These cross-sectional findings suggest that alterations in the cholinergic system from organophosphate exposures can increase fT4 levels coupled with a beyond-compensatory downregulation of TSH in female adolescents. This is the first study to characterize these associations in adolescents.