We report on the discovery of norbornyl moiety as a novel structural motif for cyclin-dependent kinase 2 (CDK2) inhibitors which was identified by screening a carbocyclic nucleoside analogue library. Three micromolar hits were expanded by the use of medicinal chemistry methods into a series of 16 novel compounds. They had prevailingly micromolar activities against CDK2 and the best compound of the series attained IC50 of 190 nM. The binding modes were explored in molecular details by modeling and docking. Quantum mechanics-based scoring was used to rationalize the affinities. In conclusion, the discovered 9-hydroxymethylnorbornyl moiety was shown by joint experimental-theoretical efforts to be able to serve as a novel substituent for CDK2 inhibitors. This finding opens door to the exploration of chemical space towards more effective derivatives targeting this important class of protein kinases.
- MeSH
- cyklin-dependentní kinasa 2 antagonisté a inhibitory MeSH
- inhibitory proteinkinas farmakologie MeSH
- norbornany farmakologie MeSH
- nukleosidy analogy a deriváty MeSH
- simulace molekulového dockingu MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Tick-borne encephalitis virus (TBEV) causes a severe and potentially fatal neuroinfection in humans. Despite its high medical relevance, no specific antiviral therapy is currently available. Here we demonstrate that treatment with a nucleoside analog, 7-deaza-2'-C-methyladenosine (7-deaza-2'-CMA), substantially improved disease outcomes, increased survival, and reduced signs of neuroinfection and viral titers in the brains of mice infected with a lethal dose of TBEV. To investigate the mechanism of action of 7-deaza-2'-CMA, two drug-resistant TBEV clones were generated and characterized. The two clones shared a signature amino acid substitution, S603T, in the viral NS5 RNA-dependent RNA polymerase (RdRp) domain. This mutation conferred resistance to various 2'-C-methylated nucleoside derivatives, but no cross-resistance was seen with other nucleoside analogs, such as 4'-C-azidocytidine and 2'-deoxy-2'-beta-hydroxy-4'-azidocytidine (RO-9187). All-atom molecular dynamics simulations revealed that the S603T RdRp mutant repels a water molecule that coordinates the position of a metal ion cofactor as 2'-C-methylated nucleoside analogs approach the active site. To investigate its phenotype, the S603T mutation was introduced into a recombinant TBEV strain (Oshima-IC) generated from an infectious cDNA clone and into a TBEV replicon that expresses a reporter luciferase gene (Oshima-REP-luc2A). The mutants were replication impaired, showing reduced growth and a small plaque size in mammalian cell culture and reduced levels of neuroinvasiveness and neurovirulence in rodent models. These results indicate that TBEV resistance to 2'-C-methylated nucleoside inhibitors is conferred by a single conservative mutation that causes a subtle atomic effect within the active site of the viral NS5 RdRp and is associated with strong attenuation of the virus.IMPORTANCE This study found that the nucleoside analog 7-deaza-2'-C-methyladenosine (7-deaza-2'-CMA) has high antiviral activity against tick-borne encephalitis virus (TBEV), a pathogen that causes severe human neuroinfections in large areas of Europe and Asia and for which there is currently no specific therapy. Treating mice infected with a lethal dose of TBEV with 7-deaza-2'-CMA resulted in significantly higher survival rates and reduced the severity of neurological signs of the disease. Thus, this compound shows promise for further development as an anti-TBEV drug. It is important to generate drug-resistant mutants to understand how the drug works and to develop guidelines for patient treatment. We generated TBEV mutants that were resistant not only to 7-deaza-2'-CMA but also to a broad range of other 2'-C-methylated antiviral medications. Our findings suggest that combination therapy may be used to improve treatment and reduce the emergence of drug-resistant viruses during nucleoside analog therapy for TBEV infection.
- MeSH
- antivirové látky terapeutické užití MeSH
- mutace MeSH
- myši MeSH
- nukleosidy * analogy a deriváty terapeutické užití MeSH
- virová léková rezistence MeSH
- viry klíšťové encefalitidy * účinky léků MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Tento článek uvádí soubor nových antivirotik účinných na lidský cytomegalovirus v klinickém stadiu výzkumu. Cytomegalovirus je velmi častým patogenem oportunních virových infekcí u pacientů po prodělané transplantaci a u pacientů se syndromem získané imunodeficiencce. Léčba cytomegalovirové infekce a onemocnění ganciclovirem, foscarnetem a cidofovirem je často svázána s výskytem závažných nežádoucích účinků a se vznikem virové rezistence. Lobucavir, adefovir, benzimidavir (TCRB), BDCRB a fomivirsen představují nová anti-CMV léčivava, která á se nacházejí v různých fázích klinického výzkumu a která představují nové terapeutické možnosti v léčbě CMV infekcí a onemocnění. Uvádíme zde především mechanismy antivirového účinku těchto nových antivirotik a mechanismy rezistence vůči těmto novým antivirovým lékům.
This review summarizes new antiviral drugs against human cytomegalovirus used in clinical research. Cytomegalovirus is the most common pathogen of opportunistic viral infections in transplant recipients and in patients with acquired immunodeficiency syndrome. The treatment of cytomegalovirus infection and disease by ganciclovir, foscarnet and cidofovir is frequently associated with severe side effects and the formation of viral resistance. Lobucavir, adefovir, benzimidavir (TCRB), BDCRB and fomivirsen are a new anti-CMV drugs in different phases of clinical studies and represent new therapeutic possibilities in the treatment of CMV infections and disease. Primarily, we have presented the antiviral mechanisms of action of these new antiviral agents and mechanisms of viral resistance to these new antiviral drugs.
