RESUMO
Farmers from South Asian countries spray insecticides without protective gear, which leads to insecticide exposure through dermal and nasal routes. Acetylcholinesterase plays a crucial role in controlling neuromuscular function. Organophosphate and carbamate insecticides inhibit acetylcholinesterase, which leads to severe neuronal/cognitive dysfunction, breathing disorders, loss of endurance, and death. To address this issue, an Oxime-fabric is developed by covalently attaching silyl-pralidoxime to the cellulose of the fabric. The Oxime-fabric, when stitched as a bodysuit and facemask, efficiently deactivates insecticides (organophosphates and carbamates) upon contact, preventing exposure. The Oxime-fabric prevents insecticide-induced neuronal damage, neuro-muscular dysfunction, and loss of endurance. Furthermore, we observe a 100% survival rate in rats when repeatedly exposed to organophosphate-insecticide through the Oxime-fabric, while no survival is seen when organophosphate-insecticide applied directly or through normal fabric. The Oxime-fabric is washable and reusable for at least 50 cycles, providing an affordable solution to prevent insecticide-induced toxicity and lethality among farmers.
Assuntos
Inseticidas , Oximas , Animais , Inseticidas/toxicidade , Ratos , Oximas/administração & dosagem , Oximas/farmacologia , Masculino , Compostos de Pralidoxima/farmacologia , Compostos de Pralidoxima/administração & dosagem , Têxteis , Inibidores da Colinesterase/administração & dosagem , Inibidores da Colinesterase/toxicidade , Acetilcolinesterase/metabolismo , Exposição Ocupacional/prevenção & controle , Exposição Ocupacional/efeitos adversos , Carbamatos/farmacologia , Carbamatos/administração & dosagem , Organofosfatos/toxicidade , Administração IntranasalRESUMO
Rising global population and increased food demands have resulted in the increased use of organophosphate pesticides (OPs), leading to toxin accumulation and transmission to humans. Pralidoxime (2-PAM), an FDA-approved drug, serves as an antidote for OP therapy. However, the atomic-level detoxification mechanisms regarding the design of novel antidotes remain unclear. This is the first study to examine the binding and unbinding pathways of 2-PAM to human acetylcholinesterase (HuAChE) through three identified doors using an enhanced sampling method called ligand-binding parallel cascade selection molecular dynamics (LB-PaCS-MD). Remarkably, LB-PaCS-MD could identify a predominant in-line binding mechanism through the acyl door at 63.79% ± 6.83%, also implicating it in a potential unbinding route (90.14% ± 4.22%). Interestingly, crucial conformational shifts in key residues, W86, Y341, and Y449, and the Ω loop significantly affect door dynamics and ligand binding modes. The LB-PaCS-MD technique can study ligand-binding pathways, thereby contributing to the design of antidotes and covalent drugs.
Assuntos
Acetilcolinesterase , Inibidores da Colinesterase , Simulação de Dinâmica Molecular , Humanos , Acetilcolinesterase/metabolismo , Acetilcolinesterase/química , Antídotos/química , Antídotos/farmacologia , Antídotos/metabolismo , Sítios de Ligação , Inibidores da Colinesterase/química , Inibidores da Colinesterase/metabolismo , Inibidores da Colinesterase/farmacologia , Ligantes , Compostos de Pralidoxima/química , Compostos de Pralidoxima/metabolismo , Compostos de Pralidoxima/farmacologia , Ligação ProteicaRESUMO
Introduction: Organophosphates are among the deadliest of known chemicals based on their ability to inactivate acetylcholinesterase in neuromuscular junctions and synapses of the central and peripheral nervous systems. The consequent accumulation of acetylcholine can produce severe acute toxicities and death. Oxime antidotes act by reactivating acetylcholinesterase with the only such reactivator approved for use in the United States being 2-pyridine aldoxime methyl chloride (a.k.a., pralidoxime or 2-PAM). However, this compound does not cross the blood-brain barrier readily and so is limited in its ability to reactivate acetylcholinesterase in the brain. Methods: We have developed a novel formulation of 2-PAM by encapsulating it within a nanocomplex designed to cross the blood-brain barrier via transferrin receptor-mediated transcytosis. This nanocomplex (termed scL-2PAM) has been subjected to head-to-head comparisons with unencapsulated 2-PAM in mice exposed to paraoxon, an organophosphate with anticholinesterase activity. Results and Discussion: In mice exposed to a sublethal dose of paraoxon, scL-2PAM reduced the extent and duration of cholinergic symptoms more effectively than did unencapsulated 2-PAM. The scL-2PAM formulation was also more effective than unencapsulated 2-PAM in rescuing mice from death after exposure to otherwise-lethal levels of paraoxon. Improved survival rates in paraoxon-exposed mice were accompanied by a higher degree of reactivation of brain acetylcholinesterase. Conclusion: Our data indicate that scL-2PAM is superior to the currently used form of 2-PAM in terms of both mitigating paraoxon toxicity in mice and reactivating acetylcholinesterase in their brains.
Assuntos
Inibidores da Colinesterase , Reativadores da Colinesterase , Paraoxon , Compostos de Pralidoxima , Animais , Camundongos , Acetilcolinesterase/metabolismo , Encéfalo/metabolismo , Inibidores da Colinesterase/toxicidade , Reativadores da Colinesterase/farmacologia , Reativadores da Colinesterase/química , Organofosfatos , Oximas/farmacologia , Oximas/química , Paraoxon/toxicidade , Paraoxon/química , Compostos de Pralidoxima/química , Compostos de Pralidoxima/farmacologiaRESUMO
Se han sintetizado una nueva familia de depresores del Sistema Nervioso Central, basado en un sistema denominado actualmente la 'utilización de fragmentos'. A uno de los fármacos obtenidos por este procedimiento la OMS le asignó el nombre de picobenzida. Al tratarse de una benzamida sustituida se prepararon análogos modificando los sustituyentes del anillo aromático y se llevó a cabo un estudio QSAR de la serie, que condujo a la optimización de la misma. Un ensayo para modificar el anillo de piridina condujo a una nueva reacción de dimerización para esta clase de compuestos (AU)
A new family of central nervous system depressants has been synthesized, applying the methodology now known as the 'use of fragments'. One of the drugs produced by this process was assigned the name picobencide by WHO. Being a substituted benzamide, analogues were prepared modifying the substituents of the aromatic ring. A QSAR study was carried out which led to the optimization of the series. A test to modify the pyridine ring led to a new dimerization reaction of this kind of compounds (AU)