Organophosphorus nerve agents pose a global threat to both military personnel and civilian population, because of their high acute toxicity and insufficient medical countermeasures. Commonly used drugs could ameliorate the intoxication and overall medical outcomes. In this study, we tested the drugs able to alleviate the symptoms of Alzheimer's disease (donepezil, huperzine A, memantine) or Parkinson's disease (procyclidine). They were administered to mice before soman intoxication in terms of their: i) protection potential against soman toxicity and ii) influence on post-exposure therapy consisting of atropine and asoxime (also known as oxime HI-6). Their pretreatment effect was not significant, when administered alone, but in combination (acetylcholinesterase inhibitor such as denepezil or huperzine A with NMDA antagonist such as memantine or procyclidine) they lowered the soman toxicity more than twice. These combinations also positively influenced the efficacy of post-exposure treatment in a similar fashion; the combinations increased the therapeutic effectiveness of antidotal treatment. In conclusion, the most effective combination - huperzine A and procyclidine - lowered the toxicity three times and improved the post-exposure therapy efficacy more than six times. These results are unprecedented in the published literature.
- MeSH
- acetylcholinesterasa metabolismus MeSH
- antidota terapeutické užití MeSH
- atropin terapeutické užití farmakologie MeSH
- cholinesterasové inhibitory toxicita MeSH
- jedy * MeSH
- memantin terapeutické užití MeSH
- míra přežití MeSH
- myši MeSH
- oximy terapeutické užití farmakologie MeSH
- procyklidin farmakologie MeSH
- pyridinové sloučeniny farmakologie MeSH
- receptory N-methyl-D-aspartátu MeSH
- soman * toxicita MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Robust quantitative structure-activity relationships (QSARs) for hBACE-1 inhibitors (pIC50) for a large database (n = 1706) are established. New statistical criteria of the predictive potential of models are suggested and tested. These criteria are the index of ideality of correlation (IIC) and the correlation intensity index (CII). The system of self-consistent models is a new approach to validate the predictive potential of QSAR-models. The statistical quality of models obtained using the CORAL software (http://www.insilico.eu/coral) for the validation sets is characterized by the average determination coefficient R2v= 0.923, and RMSE = 0.345. Three new promising molecular structures which can become inhibitors hBACE-1 are suggested.
Therapeutic efficacy of antidotal treatment of acute poisoning by nerve agents is generally assessed by the evaluation of LD50 values of nerve agents over 24 h following poisoning without or with a single administration of antidotal treatment. In this study, LD50 values of four nerve agents (sarin, soman, tabun and cyclosarin) for non-treated and treated poisoning were evaluated in mice for two experimental end points - 6 h and 24 h. While the efficacy of atropine or oxime-based antidotal treatment was the same regardless of the experimental end point, the therapeutic efficacy of all three newly developed bispyridinium non-oxime compounds (MB408, MB442, and MB444) was mostly slightly higher at the 6 h end point compared to the 24 h end point, although the therapeutic efficacy of MB compounds was not superior to oxime-based antidotal treatment. These results contrast with a study in guinea-pigs using a structurally-related compound, MB327, which showed a striking increase in protection at 6 h compared to 24 h. It is suggested that the disparity may be due to pharmacokinetic differences between the two animal species.
- MeSH
- antidota farmakologie MeSH
- časové faktory MeSH
- chemické bojové látky toxicita MeSH
- LD50 MeSH
- myši MeSH
- nikotinoví antagonisté farmakologie MeSH
- organofosfáty toxicita MeSH
- organofosforové sloučeniny toxicita MeSH
- otrava organofosfáty farmakoterapie etiologie MeSH
- oximy farmakologie MeSH
- pyridinové sloučeniny farmakologie MeSH
- reaktivátory cholinesterázy farmakologie MeSH
- sarin toxicita MeSH
- soman toxicita MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
3-dimensional (3D) cell cultures are being increasingly recognized as physiologically more relevant in vitro models than traditional monolayer cultures, because they better mimic in vivo-like microenvironment, cell-cell and cell-extracellular matrix interactions. Nevertheless, the broader use of 3D models might be limited by requirements for special consumables, equipment, or skills for 3D cell cultures, and by their limited throughput and scalability. In this study, we optimized and adapted a commercially available agarose-micromolding technique to produce scaffold-free spheroid cultures. Brightfield microscopy was used for routine nondestructive and noninvasive evaluation of spheroid formation and growth. The workflow is compatible with manual, as well as high speed automated microscopic image acquisition, and it is supplemented with an in-house developed macro 'Spheroid_Finder' for open source software Fiji to facilitate rapid automated image analysis. This protocol was used to characterize and quantify spheroid formation and growth of two different hepatic cell lines, hTERT immortalized, but non-cancerous, adult human liver stem cell line HL1-hT1, and human hepatocellular carcinoma cell line HepG2, as well as their responses to a model antiproliferative and cytotoxic agent, 5-fluorouracil. The complete protocol provides a simple and ready-to-use solution to initiate scaffold-free spheroid cultures in any laboratory with standard equipment for mammalian in vitro cell culture work. Thus, it allows to increase throughput and scale of spheroid culture experiments, which can be greatly utilized in different areas of biomedical, pharmaceutical and toxicological research.
- MeSH
- antimetabolity antitumorózní farmakologie toxicita MeSH
- buněčné kultury MeSH
- buněčné sféroidy MeSH
- buňky Hep G2 MeSH
- časové faktory MeSH
- fluorouracil farmakologie toxicita MeSH
- hepatocelulární karcinom farmakoterapie metabolismus patologie MeSH
- játra účinky léků metabolismus patologie MeSH
- kmenové buňky účinky léků metabolismus patologie MeSH
- léky antitumorózní - screeningové testy MeSH
- lidé MeSH
- nádory jater farmakoterapie metabolismus patologie MeSH
- proliferace buněk účinky léků MeSH
- průběh práce MeSH
- rychlé screeningové testy * MeSH
- testy toxicity MeSH
- viabilita buněk účinky léků MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
Organophosphate (OP) poisoning is a major global health issue; while compounds from this group have been used intensively over the last century, an effective antidote is still lacking. Oxime-type acetylcholinesterase (AChE) reactivators are used to reactivate the OP inhibited AChE. Pralidoxime is the only US Food and Drug Administration approved oxime for therapeutic use but its efficacy has been disappointing. Two novel oximes (K378 and K727) were investigated in silico and in vitro and compared with an experimental oxime (kamiloxime; K-27) and pralidoxime. In silico the molecular interactions between AChE and oximes were examined and binding energies were assessed. LogP (predicted log of the octanol/water partition coefficient) was estimated. In vitro the intrinsic ability of the oximes to inhibit AChE (IC50) and their reactivation potency (R50) when used in paraoxon inhibited human RBC-AChE was determined. Molecular docking revealed that K378 and K727 bind to the peripheral site(s) with high binding energies in contrast to the central binding of K-27 and pralidoxime. LogP values indicating that the novel compounds are significantly less hydrophilic than K-27 or pralidoxime. IC50 of K378 and K727 were comparable (0.9 and 1 µM, respectively) but orders of magnitude lower than comparators. R50 values revealed their inability to reactivate paraoxon inhibited AChE. It is concluded that the novel oximes K378 and K727 are unlikely to be clinically useful. The in silico and in vitro studies described allow avoidance of unnecessary in vivo animal work and contribute to the reduction of laboratory animal use.
- MeSH
- acetylcholinesterasa krev chemie MeSH
- antidota chemie metabolismus farmakologie MeSH
- cholinesterasové inhibitory chemie metabolismus toxicita MeSH
- GPI-vázané proteiny antagonisté a inhibitory krev chemie MeSH
- konformace proteinů MeSH
- lidé MeSH
- otrava organofosfáty krev farmakoterapie enzymologie MeSH
- oximy chemie metabolismus farmakologie MeSH
- paraoxon analogy a deriváty chemie metabolismus toxicita MeSH
- pralidoximové sloučeniny chemie metabolismus farmakologie MeSH
- pyridinové sloučeniny chemie metabolismus farmakologie MeSH
- reaktivátory cholinesterázy chemie metabolismus farmakologie MeSH
- simulace molekulového dockingu * MeSH
- vazba proteinů MeSH
- vazebná místa MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Check Tag
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Sulfur mustard, in a chemical name bis(2-chloroethyl) sulfide, is a chemical warfare agent. It is cytotoxic and blister forming once spread over the skin. Though exact molecular mechanism of sulfur mustard toxic action remains unknown, inflammation and oxidative stress development are considered as the most relevant pathological consequences. Applications of either low-molecular weight antioxidants or cofactors for enzymatic antioxidants are considered as suitable ways how to ameliorate the poisoning. In this article, survey of literature on countermeasures against sulfur mustard poisoning are given and evidence of oxidative stress role during sulfur mustard poisoning and availability of antioxidants for the therapy are discussed.
The ability of two newly developed bispyridinium oximes (K920, K923) to reduce tabun-induced acute neurotoxic signs and symptoms was compared with the oxime K203 and trimedoxime using a functional observational battery (FOB). The neuroprotective effects of the oximes studied combined with atropine on rats poisoned with tabun at a sublethal dose (130 μg/kg i.m.; 80% of LD50 value) were evaluated. Tabun-induced neurotoxicity was monitored by FOB at 2 h after tabun administration. The results indicate that all tested oximes combined with atropine enable tabun-poisoned rats to survive till the end of experiment while one non-treated tabun-poisoned rat died within 2 h. Both newly developed oximes (K920, K923) combined with atropine were able to markedly decrease tabun-induced neurotoxicity in the case of sublethal poisoning although they did not eliminate all tabun-induced acute neurotoxic signs and symptoms. Their ability to decrease tabun-induced acute neurotoxicity did not prevail the neuroprotective efficacy of trimedoxime and the oxime K203. Therefore, the newly developed oximes are not suitable for the replacement of currently available oximes (especially trimedoxime) in the treatment of acute tabun poisonings.
- MeSH
- molekulární struktura MeSH
- neuroprotektivní látky chemie terapeutické užití MeSH
- neurotoxické syndromy etiologie prevence a kontrola MeSH
- organofosfáty toxicita MeSH
- oximy chemie terapeutické užití MeSH
- potkani Wistar MeSH
- pyridinové sloučeniny chemie terapeutické užití MeSH
- reaktivátory cholinesterázy chemie terapeutické užití MeSH
- trimedoxim chemie terapeutické užití MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
Organophosphate (OP)-based pesticides and nerve agents are highly toxic compounds which interrupt the catalytic mechanism of acetylcholinesterase (AChE) by phosphorylating the hydroxyl moiety of serine residue. The inhibited enzyme can be reactivated by the nucleophilic action of oxime reactivators. To analyze the effect of different AChE sources on reactivation efficacy of reactivators, several in vivo studies have carried out using variety of AChE sources like pig, rat and monkey. Investigations on species differences provide a better insight for the development of new reactivators. Hence, present study was mainly targeted on comparative analysis of the reactivation of electric eel and human AChE inhibited by different OP. A series of butene-linked bis-pyridinium mono oximes which vary in functional groups present at the second pyridinium ring have been examined against sarin, VX, tabun and ethyl-paraoxon-poisoned AChE. In case of tabun-inhibited AChEs, tested oximes were better than reference oximes. For VX-poisoned human AChE, reactivator K251 (kr2;1.51 mM (-) (1 )min (-) (1)) showed good reactivation efficacy with standard oximes. Studies stipulated that butene-linked oximes consisting of different functional moieties are good reactivators and found to have better efficacy to reactivate nerve agent-inhibited human AChE in comparison to eel AChE.
- MeSH
- acetylcholinesterasa metabolismus MeSH
- časové faktory MeSH
- cholinesterasové inhibitory farmakologie MeSH
- dospělí MeSH
- Electrophorus MeSH
- erytrocytární membrána účinky léků enzymologie MeSH
- kinetika MeSH
- lidé MeSH
- organofosfáty farmakologie MeSH
- oximy farmakologie MeSH
- reaktivátory cholinesterázy farmakologie MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- zvířata MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
The potency of the bispyridinium non-oxime compound MB327 [1,1'-(propane-1,3-diyl)bis(4-tert-butylpyridinium) diiodide] to increase the therapeutic efficacy of the standard antidotal treatment (atropine in combination with an oxime) of acute poisoning with organophosphorus nerve agents was studied in vivo. The therapeutic efficacy of atropine alone - or atropine in combination with an oxime, MB327, or both an oxime and MB237 - was evaluated by the determination of LD50 values of several nerve agents (tabun, sarin and soman) in mice with and without treatment. The addition of MB327 increased the therapeutic efficacy of atropine alone, and atropine in combination with an oxime, against all three nerve agents, although differences in the LD50 values only reached statistical significance for sarin. In conclusion, the addition of the compound MB327 to the standard antidotal treatment of acute poisonings with nerve agents was beneficial regardless of the chemical structure of the nerve agent, although at the dose employed, MB327 in combination with atropine, or atropine and an oxime, provided only a modest increase in protection ratio. These results from mice, and previous ones from guinea-pigs, provide consistent evidence for additional, albeit modest, efficacy resulting from the inclusion of the antinicotinic compound MB327 in standard antidotal therapy. Given the typically steep probit slope for the dose-lethality relationship for nerve agents, such modest increases in protection ratio could provide significant survival benefit.
- MeSH
- antidota aplikace a dávkování terapeutické užití toxicita MeSH
- atropin aplikace a dávkování terapeutické užití toxicita MeSH
- inbrední kmeny myší MeSH
- kombinovaná farmakoterapie MeSH
- LD50 MeSH
- molekulární struktura MeSH
- nervová bojová látka otrava MeSH
- otrava farmakoterapie MeSH
- oximy aplikace a dávkování terapeutické užití toxicita MeSH
- pyridinové sloučeniny aplikace a dávkování chemická syntéza terapeutické užití toxicita MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Some environmental pollutants derived from industrial processes have been suggested to be responsible for neurological impairment in children, especially in heavily polluted areas. Since these compounds are usually activators of aryl hydrocarbon receptor (AhR), it would be important to better understand the molecular pathways downstream of AhR leading to neural deficits. To this purpose, appropriate in vitro human neural model is much needed. Here we have investigated whether undifferentiated and neuronally differentiated human neuroblastoma cells, SH-SY5Y cells, can provide a suitable model for monitoring AhR activity induced by environmental pollutants, focusing on 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD), a known activator of AhR. Further characterization of differentiated SH-SY5Y showed an increase in AhRR (aryl hydrocarbon receptor repressor), no change in ARNT1 (AhR nuclear translocator 1), and a decrease in ARNT2 expression with differentiation; in contrast, AhR was undetectable in both undifferentiated and differentiated cells. Nonetheless, treatment of parental as well as differentiated SH-SY5Y cells with TCDD resulted in the induction of AhR-regulated genes, CYP1A1 and CYP1B1; AhRR expression was also affected, but to a much smaller extent. These results indicate that undifferentiated SH-SY5Y are less sensitive to TCDD than neuronally differentiated ones, suggesting a higher resistance of the undifferentiated tumor cells to toxic insults. They also suggest that TCDD in these cells may not act via direct activation of AhR that is undetectable in SH-SY5Y as well as in differentiated neurons. Hence, these cells do not provide an appropriate model for studying ligand-mediated activation of AhR.
- MeSH
- buněčná diferenciace účinky léků MeSH
- hepatocyty účinky léků MeSH
- kultivační média bez séra MeSH
- kvantitativní polymerázová řetězová reakce MeSH
- látky znečišťující životní prostředí toxicita MeSH
- léková rezistence účinky léků genetika MeSH
- lidé MeSH
- ligandy MeSH
- nádorové buněčné linie MeSH
- neurony účinky léků metabolismus ultrastruktura MeSH
- polychlorované dibenzodioxiny toxicita MeSH
- primární buněčná kultura MeSH
- receptory aromatických uhlovodíků genetika MeSH
- regulace genové exprese účinky léků MeSH
- vztah mezi dávkou a účinkem léčiva MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
