Organophosphorus compounds are highly toxic irreversible inhibitors of cholinesterases, causing the disruption of cholinergic functions. Treatment of poisoning includes causal antidotes (oximes) used as reactivators of inhibited cholinesterases, such as pralidoxime. In this work, new halogenated oxime reactivators derived from pralidoxime were developed. The oximes were designed with a halogen substituent that lowers the pKa and enhances oximate formation. Their synthesis, stability, physicochemical properties, inhibition of native cholinesterases, and in vitro reactivation of organophosphate-inhibited cholinesterases were investigated. A series of C4 and C6 halogenated oximes showed instability and their degradation products were identified, while C3 and C5 oximes exhibited sufficient stability for the evaluation. C3 oximes displayed overall low inhibition of cholinesterases and high reactivation ability of organophosphate-inhibited cholinesterases compared to pralidoxime, indicating the significant impact of halogen substitution on reactivation ability.

• Publikační typ
• časopisecké články MeSH

Cyclophilin D (CypD) is a mitochondrial enzyme widely accepted as a regulator of the mitochondrial permeability transition pore (mPTP). Excessive opening of mPTP is associated with mitochondrial dysfunction and the development of various diseases; thus, suppression of mPTP opening through CypD inhibition presents a promising therapeutic approach. However, only a limited number of selective CypD inhibitors are currently available. In this study, 10 derivatives of 2-(benzyloxy)arylurea similar or identical to previously published CypD/mPTP inhibitors were synthesized. Unlike the original reports that assessed the opening of mPTP at the cellular level, the compounds were tested directly on the purified CypD enzyme to validate their putative mechanism of action. Additionally, the effect of the selected compounds was tested on isolated mitochondria. The obtained results show that the compounds are only weak inhibitors of CypD and mPTP opening, which is in contrast to previous conclusions drawn from the unspecific cellular JC-1 assay.

• Publikační typ
• časopisecké články MeSH

6-Nitrobenzo[b]thiophene 1,1-dioxide (Stattic) is a potent signal transducer and activator of the transcription 3 (STAT3) inhibitor developed originally for anticancer therapy. However, Stattic harbors several STAT3 inhibition-independent biological effects. To improve the properties of Stattic, we prepared a series of analogues derived from 6-aminobenzo[b]thiophene 1,1-dioxide, a compound directly obtained from the reduction of Stattic, that includes a methoxybenzylamino derivative (K2071) with optimized physicochemical characteristics, including the ability to cross the blood-brain barrier. Besides inhibiting the interleukin-6-stimulated activity of STAT3 mediated by tyrosine 705 phosphorylation, K2071 also showed cytotoxicity against a set of human glioblastoma-derived cell lines. In contrast to the core compound, a part of K2071 cytotoxicity reflected a STAT3 inhibition-independent block of mitotic progression in the prophase, affecting mitotic spindle formation, indicating that K2071 also acts as a mitotic poison. Compared to Stattic, K2071 was significantly less thiol-reactive. In addition, K2071 affected cell migration, suppressed cell proliferation in tumor spheroids, exerted cytotoxicity for glioblastoma temozolomide-induced senescent cells, and inhibited the secretion of the proinflammatory cytokine monocyte chemoattractant protein 1 (MCP-1) in senescent cells. Importantly, K2071 was well tolerated in mice, lacking manifestations of acute toxicity. The structure-activity relationship analysis of the K2071 molecule revealed the necessity of the para-substituted methoxyphenyl motif for antimitotic but not overall cytotoxic activity of its derivatives. Altogether, these results indicate that compound K2071 is a novel Stattic-derived STAT3 inhibitor and a mitotic poison with anticancer and senotherapeutic properties that is effective on glioblastoma cells and may be further developed as an agent for glioblastoma therapy.

• Publikační typ
• časopisecké články MeSH

Plasmonic photothermal therapy (PPTT) employing plasmonic gold nanorods (GNRs) presents a potent strategy for eradication of tumors including aggressive brain gliomas. Despite its promise, there is a pressing need for a more comprehensive evaluation of PPTT using sophisticated in vitro models that closely resemble tumor tissues, thereby facilitating the elucidation of therapeutic mechanisms. In this study, we exposed 3D glioma spheroids (tumoroids) to (16-mercaptohexadecyl)trimethylammonium bromide-functionalized gold nanorods (MTAB-GNRs) and a near-infrared (NIR) laser. We demonstrate that the photothermal effect can be fine-tuned by adjusting the nanoparticle concentration and laser power. Depending on the selected parameters, the laser can trigger either regulated or non-regulated cell death (necrosis) in both mouse GL261 and human U-87 MG glioma cell lines, accompanied by translocation of phosphatidylserine in the membrane. Our investigation into the mechanism of regulated cell death induced by PPTT revealed an absence of markers associated with classical apoptosis pathways, such as cleaved caspase 3. Instead, we observed the presence of cleaved caspase 1, gasdermin D, and elevated levels of NLRP3 in NIR-irradiated tumoroids, indicating the activation of pyroptosis. This finding correlates with previous observations of lysosomal accumulation of MTAB-GNRs and the known lysosomal pathway of pyroptosis activation. We further confirmed the absence of toxic breakdown products of GNRs using electron microscopy, which showed no melting or fragmentation of gold nanoparticles under the conditions causing regulated cell death. In conclusion, PPTT using coated gold nanorods offers significant potential for glioma cell elimination occurring through the activation of pyroptosis rather than classical apoptosis pathways.

• MeSH
• buněčné sféroidy účinky léků   patologie   MeSH
• fototermální terapie MeSH
• gliom * patologie   farmakoterapie   metabolismus   MeSH
• kationty chemie   farmakologie   MeSH
• kovové nanočástice chemie   MeSH
• kvartérní amoniové sloučeniny chemie   farmakologie   MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádorové buňky kultivované MeSH
• nanotrubičky * chemie   MeSH
• pyroptóza * účinky léků   MeSH
• viabilita buněk účinky léků   MeSH
• zlato * chemie   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Small molecules that exhibit broad-spectrum enteroviral inhibitory activity by targeting viral replication proteins are highly desired in antiviral drug discovery studies. To discover new human rhinovirus (hRV) inhibitors, we performed a high-throughput screening of 100,000 compounds from the Korea Chemical Bank library. This search led to identification of two phosphatidylinositol-4-kinase IIIβ (PI4KIIIβ) inhibitors having the pyrazolo-pyrimidine core structure, which display moderate anti-rhinoviral activity along with mild cytotoxicity. The results of a study aimed at optimizing the activity of the hit compounds showed that the pyrazolo-pyrimidine derivative 6f exhibits the highest activity (EC50 = 0.044, 0.066, and 0.083 μM for hRV-B14, hRV-A16, and hRV-A21, respectively) and moderate toxicity (CC50 = 31.38 μM). Furthermore, 6f has broad-spectrum activities against various hRVs, coxsackieviruses and other enteroviruses, such as EV-A71, EV-D68. An assessment of kinase inhibition potencies demonstrated that 6f possesses a high and selective kinase inhibition activity against PI4KIIIβ (IC50 value of 0.057 μM) and not against PI4KIIIα (>10 μM). Moreover, 6f exhibits modest hepatic stability (46.9 and 55.3 % remaining after 30 min in mouse and human liver microsomes, respectively). Finally, an in vivo study demonstrated that 6f possesses a desirable pharmacokinetic profile reflected in low systemic clearance (0.48 L∙h-1 kg-1) and modest oral bioavailability (52.4 %). Hence, 6f (KR-26549) appears to be an ideal lead for the development of new antiviral drugs.

• MeSH
• antivirové látky * farmakologie   chemie   chemická syntéza   MeSH
• fosfotransferasy s alkoholovou skupinou jako akceptorem MeSH
• inhibitory proteinkinas farmakologie   chemie   chemická syntéza   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• molekulární struktura MeSH
• myši MeSH
• pyrazoly farmakologie   chemie   chemická syntéza   MeSH
• pyrimidiny * farmakologie   chemie   chemická syntéza   MeSH
• replikace viru * účinky léků   MeSH
• Rhinovirus * účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

• Publikační typ
• abstrakt z konference MeSH

In this review, the current progress in the research and development of butyrylcholinesterase (BChE) reactivators is summarised and the advantages or disadvantages of these reactivators are critically discussed. Organophosphorus compounds such as nerve agents (sarin, tabun, VX) or pesticides (chlorpyrifos, diazinon) cause irreversible inhibition of acetylcholinesterase (AChE) and BChE in the human body. While AChE inhibition can be life threatening due to cholinergic overstimulation and crisis, selective BChE inhibition has presumably no adverse effects. Because BChE is mostly found in plasma, its activity is important for the scavenging of organophosphates before they can reach AChE in the central nervous system. Therefore, this enzyme in combination with its reactivator can be used as a pseudo-catalytic scavenger of organophosphates. Three structural types of BChE reactivators were found, i.e. bisquaternary salts, monoquaternary salts and uncharged compounds. Although the reviewed reactivators have certain limitations, the promising candidates for BChE reactivation were found in each structural group.

• MeSH
• acetylcholinesterasa metabolismus   chemie   MeSH
• butyrylcholinesterasa * metabolismus   chemie   MeSH
• cholinesterasové inhibitory * chemie   farmakologie   chemická syntéza   MeSH
• lidé MeSH
• molekulární struktura MeSH
• organofosforové sloučeniny * chemie   farmakologie   MeSH
• reaktivátory cholinesterasy farmakologie   chemie   chemická syntéza   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

STAT3 provides an attractive target for therapeutic approaches in cancer, and we can assume that inhibition of the STAT3 pathway can be a powerful tool for elimination of the detrimental effects of chemotherapy or to increase its effectiveness. STAT3 pathway inhibition should also increase the efficacy of antitumour immunotherapy. The objective of this collaborative project is to synthesize novel potentially drugable STAT3 inhibitors, to evaluate their inhibitory capabilities, toxicity and their impacts on (senescent) tumour cells treated with selected chemotherapeutics in comparison with existing STAT3 inhibitors. Based on the experimental chemo and/or immunotherapeutic proof of principle experiments performed, using preclinical murine tumour models, we will suggest a therapeutic scheme in which STAT3 inhibitors would eliminate the adverse effects of the genotoxic anti-tumour therapy, as well as detrimental effects of senescent cells, to prevent a development of a residual tumour disease and to increase the effectiveness of subsequent immunotherapy.

STAT3 představuje potenciální cíl pro protinádorovou terapii. Můžeme předpokládat, že inhibice STAT3 signální dráhy může být důležitým nástrojem pro eliminaci negativních efektů protinádorové chemoterapie, případně může zvýšit její efektivitu. Inhibice této signální dráhy by měla zvýšit take efektivitu protinádorové imunoterapie. Cílem tohoto projektu je připravit nové inhibitory STAT3 s potenciálním klinickým využitím, vyhodnotit jejich účinnost, toxicitu a dopady na (senescentní) nádorové buňky vystavené vlivu chemoterapeutik a srovnat je s existujícími inhibitory. Na základě chemoterapeutických a imununoterapeutických experimentů na myších preklinických modelech navrhneme terapeutická schémata, ve kterých použité STAT3 inhibitory budou schopny eliminovat negativní účinky genotoxické protinádorové chemoterapie, škodlivé účinky senescentních buněk, zabránit rozvoji zbytkové minimální nádorové choroby a zvýšit účinnost následné imunoterapie.

• Klíčová slova
• imunoterapie, imunosuprese, immunotherapy, STAT3 inhibitory, chemoterapie nádorů, onkoimunologie, STAT3 inhibitors, cancer chemotherapy, oncoimmunology, immunosuppression,

• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Dopamine is a biologically active amine synthesized in the central and peripheral nervous system. This biogenic monoamine acts by activating five types of dopamine receptors (D1-5 Rs), which belong to the G protein-coupled receptor family. Antagonists and partial agonists of D2 Rs are used to treat schizophrenia, Parkinson's disease, depression, and anxiety. The typical pharmacophore with high D2 R affinity comprises four main areas, namely aromatic moiety, cyclic amine, central linker and aromatic/heteroaromatic lipophilic fragment. From the literature reviewed herein, we can conclude that 4-(2,3-dichlorophenyl), 4-(2-methoxyphenyl)-, 4-(benzo[b]thiophen-4-yl)-1-substituted piperazine, and 4-(6-fluorobenzo[d]isoxazol-3-yl)piperidine moieties are critical for high D2 R affinity. Four to six atoms chains are optimal for D2 R affinity with 4-butoxyl as the most pronounced one. The bicyclic aromatic/heteroaromatic systems are most frequently occurring as lipophilic appendages to retain high D2 R affinity. In this review, we provide a thorough overview of the therapeutic potential of D2 R modulators in the treatment of the aforementioned disorders. In addition, this review summarizes current knowledge about these diseases, with a focus on the dopaminergic pathway underlying these pathologies. Major attention is paid to the structure, function, and pharmacology of novel D2 R ligands, which have been developed in the last decade (2010-2021), and belong to the 1,4-disubstituted aromatic cyclic amine group. Due to the abundance of data, allosteric D2 R ligands and D2 R modulators from patents are not discussed in this review.

• MeSH
• dopamin * metabolismus   MeSH
• lidé MeSH
• ligandy MeSH
• receptory dopaminu D2 * agonisté   metabolismus   MeSH
• receptory spřažené s G-proteiny MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Oxime reactivators of acetylcholinesterase are commonly used to treat highly toxic organophosphate poisoning. They are effective nucleophiles that can restore the catalytic activity of acetylcholinesterase; however, their main limitation is the difficulty in crossing the blood-brain barrier (BBB) because of their strongly hydrophilic nature. Various approaches to overcome this limitation and enhance the bioavailability of oxime reactivators in the CNS have been evaluated; these include structural modifications, conjugation with molecules that have transporters in the BBB, bypassing the BBB through intranasal delivery, and inhibition of BBB efflux transporters. A promising approach is the use of nanoparticles (NPs) as the delivery systems. Studies using mesoporous silica nanomaterials, poly (L-lysine)-graft-poly(ethylene oxide) NPs, metallic organic frameworks, poly(lactic-co-glycolic acid) NPs, human serum albumin NPs, liposomes, solid lipid NPs, and cucurbiturils, have shown promising results. Some NPs are considered as nanoreactors for organophosphate detoxification; these combine bioscavengers with encapsulated oximes. This study provides an overview and critical discussion of the strategies used to enhance the bioavailability of oxime reactivators in the central nervous system.

• MeSH
• acetylcholinesterasa * MeSH
• biologická dostupnost MeSH
• biologický transport MeSH
• centrální nervový systém * MeSH
• hematoencefalická bariéra MeSH
• lidé MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH