As some previously reported studies have proven that amodiaquine, in addition to its primary antimalarial activity, also has potential for new applications such as the inhibition of cholinesterases, in our study we focused on the evaluation of the influence of different substituents in the aminoquinoline part of the amodiaquine structure on the inhibition of human acetylcholinesterase and butyrylcholinesterase to investigate the possibility for their use as drugs for the treatment of AD. We synthesized a series of amodiaquine derivatives bearing H-, F-, CF-, NO-, CN-, COH- or CHO- groups on the aminoquinoline ring, and determined that all of the tested derivatives were very potent inhibitors of both cholinesterases, with inhibition constants () in the nM and low μM range and with prominent selectivity (up to 300 times) for the inhibition of acetylcholinesterase. All compounds displayed an ability to chelate biometal ions Fe, Zn and Cu and an antioxidant power comparable to that of standard antioxidants.
View Article and Find Full Text PDFInduction of oxidative stress and the associated lipid peroxidation is a prevalent mechanism through which certain metal(loid)s exert nephrotoxic effects in mammals. Research on the toxic impacts of metal(loid)s in free-ranging large mammals at high trophic positions is exceedingly rare, yet crucial for understanding environmental exposure scenarios relevant to both human and animal risk assessment. Renal cortex tissues (N = 457) of free-ranging brown bears (Ursus arctos) from the Dinara-Pindos population sampled in Croatia were analysed herein for toxic metal(loid)s and the underlying biological and environmental drivers of variation, with their time trend monitored during the 2009-2022 period.
View Article and Find Full Text PDFThe cholinergic system, relying on the neurotransmitter acetylcholine (ACh), plays a significant role in muscle contraction, cognition, and autonomic nervous system regulation. The enzymes acetylcholinesterase, AChE, and butyrylcholinesterase, BChE, responsible for hydrolyzing ACh, can fine-tune the cholinergic system's activity and are, therefore, excellent pharmacological targets to address a range of medical conditions. We designed, synthesized, and profiled 14 -alkyl quaternary quinuclidines as inhibitors of human AChE and BChE and analyzed their impact on cell viability to assess their safety in the context of application as potential therapeutics.
View Article and Find Full Text PDFClinical treatment with the antineoplastic drug irinotecan (IRI) is often hindered by side effects that significantly reduce the quality of life of treated patients. Due to the growing public support for products with Δ-tetrahydrocannabinol (THC), even though relevant scientific literature does not provide clear evidence of their high antitumour potential, some cancer patients take unregistered preparations containing up to 80 % THC. This study was conducted on a syngeneic colorectal cancer mouse model to test the efficiency and safety of concomitant treatment with IRI and THC.
View Article and Find Full Text PDFThe most successful therapeutic strategy in the treatment of Alzheimer's disease (AD) is directed toward increasing levels of the neurotransmitter acetylcholine (ACh) by inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), the enzymes responsible for its hydrolysis. In this paper, we extended our study on 4-aminoquinolines as human cholinesterase inhibitors on twenty-six new 4-aminoquinolines containing an n-octylamino spacer on C(4) and different substituents on the terminal amino group. We evaluated the potency of new derivatives to act as multi-targeted ligands by determining their inhibition potency towards human AChE and BChE, ability to chelate biometals Fe, Cu and Zn, ability to inhibit the action of β-secretase 1 (BACE1) and their antioxidant capacity.
View Article and Find Full Text PDFThe objective of study was to investigate the effects of different doses of simvastatin and fenofibrate on malondialdehyde (MDA) and reduced glutathione (GSH) in the plasma, liver, and brain tissue of male normolipidaemic and hyperlipidaemic rats. Normolipidaemic (Wistar) rats were receiving 10 or 50 mg/kg a day of simvastatin or 30 or 50 mg/kg a day of fenofibrate. Hyperlipidaemic (Zucker) rats were receiving 50 mg/kg/day of simvastatin or 30 mg/kg/day of fenofibrate.
View Article and Find Full Text PDFTo contribute new information to the pyrethroid pesticide α-cypermethrin toxicity profile, we evaluated its effects after oral administration to Wistar rats at daily doses of 2.186, 0.015, 0.
View Article and Find Full Text PDFConsidering that acetylcholinesterase (AChE) inhibition is the most important mode of action expected of a potential drug used for the treatment of symptoms of Alzheimer's disease (AD), our previous pilot study of 4-aminoquinolines as potential human cholinesterase inhibitors was extended to twenty-two new structurally distinct 4-aminoquinolines bearing an adamantane moiety. Inhibition studies revealed that all of the compounds were very potent inhibitors of AChE and butyrylcholinesterase (BChE), with inhibition constants () ranging between 0.075 and 25 µM.
View Article and Find Full Text PDFThe fluorinated bis-pyridinium oximes were designed and synthesized with the aim of increasing their nucleophilicity and potential to reactivate phosphorylated human recombinant acetylcholinesterase (AChE) and human purified plasmatic butyrylcholinesterase (BChE) in relation to chlorinated and non-halogenated oxime analogues. Compared to non-halogenated oximes, halogenated oximes showed lower pK of the oxime group (fluorinated < chlorinated < non-halogenated) along with higher level of oximate anion formation at the physiological pH, and had a higher binding affinity of both AChE and BChE. The stability tests showed that the fluorinated oximes were stable in water, while in buffered environment di-fluorinated oximes were prone to rapid degradation, which was reflected in their lower reactivation ability.
View Article and Find Full Text PDFImidacloprid is a neonicotinoid insecticide that acts selectively as an agonist on insect nicotinic acetylcholine receptors. It is used for crop protection worldwide, as well as for non-agricultural uses. Imidacloprid systemic accumulation in food is an important source of imidacloprid exposure.
View Article and Find Full Text PDFThis review proposes the hypothesis that the effectiveness of irinotecan chemotherapy might be impaired by high doses of concomitantly administered Δ-tetrahydrocannabinol (THC). The most important features shared by irinotecan and THC, which might represent sources of potentially harmful interactions are: first-pass hepatic metabolism mediated by cytochrome P450 (CYP) enzyme CYP3A4; glucuronidation mediated by uridine diphosphate glycosyltransferase (UGT) enzymes, isoforms 1A1 and 1A9; transport of parent compounds and their metabolites via canalicular ATP-binding cassette (ABC) transporters ABCB1 and ABCG2; enterohepatic recirculation of both parent compounds, which leads to an extended duration of their pharmacological effects; possible competition for binding to albumin; butyrylcholinesterase (BChE) inhibition by THC, which might impair the conversion of parent irinotecan into the SN-38 metabolite; mutual effects on mitochondrial dysfunction and induction of oxidative stress; potentiation of hepatotoxicity; potentiation of genotoxicity and cytogenetic effects leading to genome instability; possible neurotoxicity; and effects on bilirubin. The controversies associated with the use of highly concentrated THC preparations with irinotecan chemotherapy are also discussed.
View Article and Find Full Text PDFTembotrione is a rather novel pesticide, usually used for post-emergence weed control. Even though its use is rapidly growing, it is not followed by an adequate flow of scientific evidence regarding its toxicity towards non-target organisms. We evaluated the potential of low doses of tembotrione to induce oxidative stress and cytogenetic damage in blood and brain cells of adult male Wistar rats.
View Article and Find Full Text PDFNerve agents, the deadliest chemical warfare agents, are potent inhibitors of acetylcholinesterase (AChE) and cause rapid cholinergic crisis with serious symptoms of poisoning. Oxime reactivators of AChE are used in medical practice in the treatment of nerve agent poisoning, but the search for novel improved reactivators with central activity is an ongoing pursuit. For numerous oximes synthesized, reactivation is a standard approach in biological evaluation with little attention given to the pharmacokinetic properties of the compounds.
View Article and Find Full Text PDFCurrently we are faced with an ever-growing use of Δ-tetrahydrocannabinol (THC) preparations, often used as supportive therapies for various malignancies and neurological disorders. As some of illegally distributed forms of such preparations, like cannabis oils and butane hash oil, might contain over 80% of THC, their consumers can become intoxicated or experience various detrimental effects. This fact motivated us for the assessments of THC toxicity in vivo on a Wistar rat model, at a daily oral dose of 7 mg/kg which is comparable to those found in illicit preparations.
View Article and Find Full Text PDFAcetylcholinesterase (AChE), an enzyme that degrades the neurotransmitter acetylcholine, when covalently inhibited by organophosphorus compounds (OPs), such as nerve agents and pesticides, can be reactivated by oximes. However, tabun remains among the most dangerous nerve agents due to the low reactivation efficacy of standard pyridinium aldoxime antidotes. Therefore, finding an optimal reactivator for prophylaxis against tabun toxicity and for post-exposure treatment is a continued challenge.
View Article and Find Full Text PDFIn the development of antidotal therapy for treatment of organophosphate exposure from pesticides used in agriculture and nerve agents insidiously employed in terrorism, the alkylpyridinium aldoximes have received primary attention since their early development by I. B. Wilson in the 1950s.
View Article and Find Full Text PDFArh Hig Rada Toksikol
June 2018
This review article provides a summary of the studies relying on oxidative stress biomarkers (lipid peroxidation and antioxidant enzymes in particular) to investigate the effects of atrazine and terbuthylazine exposure in experimental animals and humans published since 2010. In general, experimental animals showed that atrazine and terbuthylazine exposure mostly affected their antioxidant defences and, to a lesser extent, lipid peroxidation, but the effects varied by the species, sex, age, herbicide concentration, and duration of exposure. Most of the studies involved aquatic organisms as useful and sensitive bio-indicators of environmental pollution and important part of the food chain.
View Article and Find Full Text PDFIn this 28 day-study, we evaluated the effects of herbicide glyphosate administered by gavage to Wistar rats at daily doses equivalent to 0.1 of the acceptable operator exposure level (AOEL), 0.5 of the consumer acceptable daily intake (ADI), 1.
View Article and Find Full Text PDFThere is growing interest regarding the use of herbal preparations based on for medicinal purposes, despite the poorly understood interactions of their main constituent Δ⁸-tetrahydrocannabinol (THC) with conventional drugs, especially cytostatics. The objective of this pilot study was to prove whether the concomitant intake of THC impaired liver function in male Wistar rats treated with the anticancer drug irinotecan (IRI), and evaluate the toxic effects associated with this exposure. IRI was administered once intraperitoneally (at 100 mg/kg of the body weight (b.
View Article and Find Full Text PDFTerbuthylazine belongs to the chloro-s-triazine group of herbicides and acts primarily as a photosynthesis inhibitor. The mechanisms of action related to its exposure, relevant both in animals and humans, are still insufficiently investigated. This comprehensive study focused on the outcomes of terbuthylazine exposure at cell level in vitro, and a mice model in vivo.
View Article and Find Full Text PDFIn this 28 day-study, we evaluated the effects of the insecticide chlorpyrifos orally administered to Wistar rats at doses 0.160, 0.015, and 0.
View Article and Find Full Text PDFTerbuthylazine is a selective pre- and post-emergency chloro-triazine herbicide used for a broad spectrum of weed control. We evaluated the potential of low doses of terbuthylazine to induce oxidative stress and cytogenetic damage in peripheral blood samples of adult male Wistar rats. Following 28-day repeated oral exposure at 0.
View Article and Find Full Text PDFWe studied the toxic effects of glyphosate in vitro on HepG2 cells exposed for 4 and 24 h to low glyphosate concentrations likely to be encountered in occupational and residential exposures [the acceptable daily intake (ADI; 0.5 μg/mL), residential exposure level (REL; 2.91 μg/mL) and occupational exposure level (OEL; 3.
View Article and Find Full Text PDFA well-considered treatment of acute nerve agents poisoning involves the exogenous administration of butyrylcholinesterase (BChE, EC 3.1.1.
View Article and Find Full Text PDFThis study evaluated the cyto- and genotoxic effects of three pesticides: α-cypermethrin, chlorpyrifos and imidacloprid applied in vitro to human lymphocytes and HepG2 cells for exposure times of 4 and 24 h at concentrations corresponding to OEL, ADI and REL. Assessments were made using oxidative stress biomarkers and the alkaline comet, cytokinesis-block micronucleus cytome and cell viability assays. Low doses of all three pesticides displayed DNA damaging potential, both in lymphocytes and HepG2 cells.
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