Itaconate, an endogenous immunomodulator from the tricarboxylic acid (TCA) cycle, shows therapeutic effects in various disease models, but is highly polar with poor cellular permeability. We previously reported a novel, topical itaconate derivative, SCD-153, for the treatment of alopecia areata. Here, we present the discovery of orally available itaconate derivatives for systemic and skin disorders. Four sets of prodrugs were synthesized using pivaloyloxymethyl (POM), isopropyloxycarbonyloxymethyl (POC), (5-methyl-2-oxo-1,3-dioxol-4-yl) methyl (ODOL), and 3-(hexadecyloxy)propyl (HDP) pro-moieties pairing with itaconic acid (IA), 1-methyl itaconate (1-MI), and 4-methyl itaconate (4-MI). Among these, POC-based prodrugs (P2, P9, P13) showed favorable stability, permeability, and pharmacokinetics. Notably, P2 and P13 significantly inhibited Poly(I:C)/IFNγ-induced inflammatory cytokines in human epidermal keratinocytes. Oral studies demonstrated favorable pharmacokinetics releasing micromolar concentrations of IA or 4-MI from P2 and P13, respectively. These findings highlight the potential of prodrug strategies to enhance itaconate's cellular permeability and oral bioavailability, paving the way for clinical translation.

• MeSH
• aplikace orální MeSH
• krysa rodu Rattus MeSH
• lidé MeSH
• myši MeSH
• objevování léků MeSH
• prekurzory léčiv * chemie   farmakologie   chemická syntéza   farmakokinetika   MeSH
• sukcináty * chemie   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• lidé MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• itaconic acid MeSH Prohlížeč
• prekurzory léčiv * MeSH
• sukcináty * MeSH

Malignant peripheral nerve sheath tumors (MPNST) are highly aggressive soft-tissue sarcomas that arise from neural tissues and carry a poor prognosis. Previously, we found that the glutamine amidotransferase inhibitor JHU395 partially impeded tumor growth in preclinical models of MPNST. JHU395 inhibits de novo purine synthesis in human MPNST cells and murine tumors with partial decreases in purine monophosphates. On the basis of prior studies showing enhanced efficacy when glutamine amidotransferase inhibition was combined with the antimetabolite 6-mercaptopurine (6-MP), we hypothesized that such a combination would be efficacious in MPNST. Given the known toxicity associated with 6-MP, we set out to develop a more efficient and well-tolerated drug that targets the purine salvage pathway. Here, we report the discovery of Pro-905, a phosphoramidate protide that delivered the active nucleotide antimetabolite thioguanosine monophosphate (TGMP) to tumors over 2.5 times better than equimolar 6-MP. Pro-905 effectively prevented the incorporation of purine salvage substrates into nucleic acids and inhibited colony formation of human MPNST cells in a dose-dependent manner. In addition, Pro-905 inhibited MPNST growth and was well-tolerated in both human patient-derived xenograft (PDX) and murine flank MPNST models. When combined with JHU395, Pro-905 enhanced the colony formation inhibitory potency of JHU395 in human MPNST cells and augmented the antitumor efficacy of JHU395 in mice. In summary, the dual inhibition of the de novo and purine salvage pathways in preclinical models may safely be used to enhance therapeutic efficacy against MPNST.

• MeSH
• antimetabolity terapeutické užití   MeSH
• glutamin MeSH
• lidé MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• nádory nervové pochvy * farmakoterapie   MeSH
• neurofibrosarkom * MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antimetabolity MeSH
• glutamin MeSH
• JHU395 MeSH Prohlížeč

Compounds with a phosphonate group, i.e., -P(O)(OH)2 group attached directly to the molecule via a P-C bond serve as suitable non-hydrolyzable phosphate mimics in various biomedical applications. In principle, they often inhibit enzymes utilizing various phosphates as substrates. In this review we focus mainly on biologically active phosphonates that originated from our institute (Institute of Organic Chemistry and Biochemistry in Prague); i.e., acyclic nucleoside phosphonates (ANPs, e.g., adefovir, tenofovir, and cidofovir) and derivatives of non-nucleoside phosphonates such as 2-(phosphonomethyl) pentanedioic acid (2-PMPA). Principal strategies of their syntheses and modifications to prodrugs is reported. Besides clinically used ANP antivirals, a special attention is paid to new biologically active molecules with respect to emerging infections and arising resistance of many pathogens against standard treatments. These new structures include 2,4-diamino-6-[2-(phosphonomethoxy)ethoxy]pyrimidines or so-called "open-ring" derivatives, acyclic nucleoside phosphonates with 5-azacytosine as a base moiety, side-chain fluorinated ANPs, aza/deazapurine ANPs. When transformed into an appropriate prodrug by derivatizing their charged functionalities, all these compounds show promising potential to become drug candidates for the treatment of viral infections. ANP prodrugs with suitable pharmacokinetics include amino acid phosphoramidates, pivaloyloxymethyl (POM) and isopropoxycarbonyloxymethyl (POC) esters, alkyl and alkoxyalkyl esters, salicylic esters, (methyl-2-oxo-1,3-dioxol-4-yl) methyl (ODOL) esters and peptidomimetic prodrugs. We also focus on the story of cytostatics related to 9-[2-(phosphonomethoxy)ethyl]guanine and its prodrugs which eventually led to development of the veterinary drug rabacfosadine. Various new ANP structures are also currently investigated as antiparasitics, especially antimalarial agents e.g., guanine and hypoxanthine derivatives with 2-(phosphonoethoxy)ethyl moiety, their thia-analogues and N-branched derivatives. In addition to ANPs and their analogs, we also describe prodrugs of 2-(phosphonomethyl)pentanedioic acid (2-PMPA), a potent inhibitor of the enzyme glutamate carboxypeptidase II (GCPII), also known as prostate-specific membrane antigen (PSMA). Glutamate carboxypeptidase II inhibitors, including 2-PMPA have been found efficacious in various preclinical models of neurological disorders which are caused by glutamatergic excitotoxicity. Unfortunately its highly polar character and hence low bioavailability severely limits its potential for clinical use. To overcome this problem, various prodrug strategies have been used to mask carboxylates and/or phosphonate functionalities with pivaloyloxymethyl, POC, ODOL and alkyl esters. Chemistry and biological characterization led to identification of prodrugs with 44-80 fold greater oral bioavailability (tetra-ODOL-2-PMPA).

• Klíčová slova
• 2-PMPA, FOLH1, GCPII, acyclic nucleoside phosphonates, antivirals, prodrugs, prostate-specific membrane antigen, protides,
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Despite the eradication of smallpox four decades ago, poxviruses continue to be a threat to humans and animals. The arsenal of anti-poxvirus agents is very limited and understanding mechanisms of resistance to agents targeting viral DNA polymerases is fundamental for the development of antiviral therapies. We describe here the phenotypic and genotypic characterization of poxvirus DNA polymerase mutants isolated under selective pressure with different acyclic nucleoside phosphonates, including HPMPC (cidofovir), cHPMPC, HPMPA, cHPMPA, HPMPDAP, HPMPO-DAPy, and PMEO-DAPy, and the pyrophosphate analogue phosphonoacetic acid. Vaccinia virus (VACV) and cowpox virus drug-resistant viral clones emerging under drug pressure were characterized phenotypically (drug-susceptibility profile) and genotypically (DNA polymerase sequencing). Different amino acid changes in the polymerase domain and in the 3'-5' exonuclease domain were linked to drug resistance. Changes in the 3'-5' domain emerged earlier than in the polymerase domain when viruses acquired a combination of mutations. Our study highlights the importance of poxvirus DNA polymerase residues 314, 613, 684, 688, and 851, previously linked to drug resistance, and identified several novel mutations in the 3'-5' exonuclease domain (M313I, F354L, D480Y) and in the DNA polymerase domain (A632T, T831I, E856K, L924F) associated with different drug-susceptibility profiles. Furthermore, a combination of mutations resulted in complex patterns of cross-resistance. Modeling of the VACV DNA polymerase bearing the newly described mutations was performed to understand the effects of these mutations on the structure of the viral enzyme. We demonstrated the emergence of drug-resistant DNA polymerase mutations in complex patterns to be considered in case such mutations should eventually arise in the clinic.

• Klíčová slova
• DNA polymerase, cidofovir, drug resistance, nucleotide analogues, phosphonoacetic acid, vaccinia virus,
• Publikační typ
• časopisecké články MeSH

Polyomavirus infections occur commonly in humans and are normally nonfatal. However, in immunocompromised individuals, they are intractable and frequently fatal. Due to a lack of approved drugs to treat polyomavirus infections, cidofovir, a phosphonate nucleotide analog approved to treat cytomegalovirus infections, has been repurposed as an antipolyomavirus agent. Cidofovir has been modified in various ways to improve its efficacies as a broad-spectrum antiviral agent. However, the actual mechanisms and targets of cidofovir and its modified derivatives as antipolyomavirus agents are still under research. Here, polyomavirus large tumor antigen (Tag) activities were identified as the viral target of cidofovir derivatives. The alkoxyalkyl ester derivatives of cidofovir efficiently inhibit polyomavirus DNA replication in cell-free human extracts and a viral in vitro replication system utilizing only purified proteins. We present evidence that DNA helicase and DNA binding activities of polyomavirus Tags are diminished in the presence of low concentrations of alkoxyalkyl ester derivatives of cidofovir, suggesting that the inhibition of viral DNA replication is at least in part mediated by inhibiting single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) binding activities of Tags. These findings show that the alkoxyalkyl ester derivatives of cidofovir are effective in vitro without undergoing further conversions, and we conclude that the inhibitory mechanisms of nucleotide analog-based drugs are more complex than previously believed.

• Klíčová slova
• ATPase, DNA helicase, DNA replication, large T antigen, nucleoside analogs, polyomavirus, protein-DNA interactions,
• MeSH
• antigeny virové nádorové * MeSH
• cytosin MeSH
• DNA virů genetika   MeSH
• estery farmakologie   MeSH
• lidé MeSH
• nukleotidy MeSH
• Polyomavirus * genetika   MeSH
• replikace DNA MeSH
• replikace viru MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antigeny virové nádorové * MeSH
• cytosin MeSH
• DNA virů MeSH
• estery MeSH
• nukleotidy MeSH

In analogy to antiviral acyclic nucleoside phosphonates, a series of 5-amino-3-oxo-1,2,4-thiadiazol-3(2H)-ones bearing a 2-phosphonomethoxyethyl (PME) or 3-hydroxy-2-(phosphonomethoxy)propyl (HPMP) group at the position 2 of the heterocyclic moiety has been synthesized. Diisopropyl esters of PME- and HPMP-amines have been converted to the N-substituted ureas and then reacted with benzoyl, ethoxycarbonyl, and Fmoc isothiocyanates to give the corresponding thiobiurets, which were oxidatively cyclized to diisopropyl esters of 5-amino-3-oxo-2-PME- or 2-HPMP- 1,2,4-thiadiazol-3(2H)-ones. The phosphonate ester groups were cleaved with bromotrimethylsilane, yielding N5-protected phosphonic acids. The subsequent attempts to remove the protecting group from N5 under alkaline conditions resulted in the cleavage of the 1,2,4-thiadiazole ring. Similarly, compounds with a previously unprotected 5-amino-1,2,4-thiadiazolone base moiety were stable only in the form of phosphonate esters. The series of twenty-one newly prepared 1,2,4-thiadiazol-3(2H)-ones were explored as potential inhibitors of cysteine-dependent enzymes - human cathepsin K (CatK) and glycogen synthase kinase 3β (GSK-3β). Several compounds exhibited an inhibitory activity toward both enzymes in the low micromolar range. The inhibitory potency of some of them toward GSK-3β was similar to that of the thiadiazole GSK-3β inhibitor tideglusib, whereas others exhibited more favorable toxicity profile while retaining good inhibitory activity.

• Klíčová slova
• 5-Amino-1,2,4-thiadiazol-3-(2H)-one, Acyclic nucleoside phosphonates, Cathepsin K, Glycogen synthase kinase 3β, Epigenetic, Thiadiazoles,
• MeSH
• buněčné linie MeSH
• inhibitory enzymů chemická syntéza   chemie   farmakologie   MeSH
• kathepsin K antagonisté a inhibitory   metabolismus   MeSH
• kinasa glykogensynthasy 3beta antagonisté a inhibitory   metabolismus   MeSH
• lidé MeSH
• molekulární struktura MeSH
• nukleosidy chemická syntéza   chemie   farmakologie   MeSH
• organofosfonáty chemická syntéza   chemie   farmakologie   MeSH
• proliferace buněk účinky léků   MeSH
• protinádorové látky chemická syntéza   chemie   farmakologie   MeSH
• screeningové testy protinádorových léčiv MeSH
• thiadiazoly chemická syntéza   chemie   farmakologie   MeSH
• viabilita buněk účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• CTSK protein, human MeSH Prohlížeč
• inhibitory enzymů MeSH
• kathepsin K MeSH
• kinasa glykogensynthasy 3beta MeSH
• nukleosidy MeSH
• organofosfonáty MeSH
• protinádorové látky MeSH
• thiadiazoly MeSH

Tuberculosis (TB) remains one of the major health concerns worldwide. Mycobacterium tuberculosis (Mtb), the causative agent of TB, can flexibly change its metabolic processes during different life stages. Regulation of key metabolic enzyme activities by intracellular conditions, allosteric inhibition or feedback control can effectively contribute to Mtb survival under different conditions. Phosphofructokinase (Pfk) is one of the key enzymes regulating glycolysis. Mtb encodes two Pfk isoenzymes, Pfk A/Rv3010c and Pfk B/Rv2029c, which are differently expressed upon transition to the hypoxia-induced non-replicating state of the bacteria. While pfkB gene and protein expression are upregulated under hypoxic conditions, Pfk A levels decrease. Here, we present biochemical characterization of both Pfk isoenzymes, revealing that Pfk A and Pfk B display different kinetic properties. Although the glycolytic activity of Pfk A is higher than that of Pfk B, it is markedly inhibited by an excess of both substrates (fructose-6-phosphate and ATP), reaction products (fructose-1,6-bisphosphate and ADP) and common metabolic allosteric regulators. In contrast, synthesis of fructose-1,6-bisphosphatase catalyzed by Pfk B is not regulated by higher levels of substrates, and metabolites. Importantly, we found that only Pfk B can catalyze the reverse gluconeogenic reaction. Pfk B thus can support glycolysis under conditions inhibiting Pfk A function.

• Klíčová slova
• Mycobacterium tuberculosis, allosteric regulation, enzyme kinetics, glycolysis, phosphofructokinase A and B,
• MeSH
• adenosindifosfát metabolismus   farmakologie   MeSH
• adenosintrifosfát metabolismus   farmakologie   MeSH
• alosterická regulace MeSH
• bakteriální proteiny antagonisté a inhibitory   metabolismus   MeSH
• enzymová indukce MeSH
• fosfofruktokinasy antagonisté a inhibitory   metabolismus   MeSH
• fruktosadifosfáty biosyntéza   farmakologie   MeSH
• fruktosafosfáty metabolismus   farmakologie   MeSH
• glukoneogeneze MeSH
• glykolýza MeSH
• hexosafosfáty metabolismus   MeSH
• izoenzymy antagonisté a inhibitory   metabolismus   MeSH
• katalýza MeSH
• kinetika MeSH
• kyslík farmakologie   MeSH
• L-laktátdehydrogenasa metabolismus   MeSH
• Mycobacterium tuberculosis účinky léků   enzymologie   MeSH
• pyruvátkinasa metabolismus   MeSH
• rekombinantní proteiny metabolismus   MeSH
• substrátová specifita MeSH
• zpětná vazba fyziologická MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• adenosindifosfát MeSH
• adenosintrifosfát MeSH
• bakteriální proteiny MeSH
• fosfofruktokinasy MeSH
• fructose-1,6-diphosphate MeSH Prohlížeč
• fructose-6-phosphate MeSH Prohlížeč
• fruktosadifosfáty MeSH
• fruktosafosfáty MeSH
• hexosafosfáty MeSH
• izoenzymy MeSH
• kyslík MeSH
• L-laktátdehydrogenasa MeSH
• phosphofructokinase A protein, Mycobacterium tuberculosis MeSH Prohlížeč
• pyruvátkinasa MeSH
• rekombinantní proteiny MeSH
• tagatose 6-phosphate MeSH Prohlížeč

Repetitive DNA sequences and some genes are epigenetically repressed by transcriptional gene silencing (TGS). When genetic mutants are not available or problematic to use, TGS can be suppressed by chemical inhibitors. However, informed use of epigenetic inhibitors is partially hampered by the absence of any systematic comparison. In addition, there is emerging evidence that epigenetic inhibitors cause genomic instability, but the nature of this damage and its repair remain unclear. To bridge these gaps, we compared the effects of 5-azacytidine (AC), 2'-deoxy-5-azacytidine (DAC), zebularine and 3-deazaneplanocin A (DZNep) on TGS and DNA damage repair. The most effective inhibitor of TGS was DAC, followed by DZNep, zebularine and AC. We confirmed that all inhibitors induce DNA damage and suggest that this damage is repaired by multiple pathways with a critical role of homologous recombination and of the SMC5/6 complex. A strong positive link between the degree of cytidine analog-induced DNA demethylation and the amount of DNA damage suggests that DNA damage is an integral part of cytidine analog-induced DNA demethylation. This helps us to understand the function of DNA methylation in plants and opens the possibility of using epigenetic inhibitors in biotechnology.

• Klíčová slova
• Arabidopsis thaliana, Vicia faba, DNA damage, DNA methylation, cytidine analog, epigenetic inhibitors, genome stability,
• MeSH
• adenosin analogy a deriváty   farmakologie   MeSH
• Arabidopsis genetika   MeSH
• azacytidin farmakologie   MeSH
• chromozomální aberace účinky léků   MeSH
• cytidin analogy a deriváty   farmakologie   MeSH
• decitabin farmakologie   MeSH
• epigeneze genetická * účinky léků   MeSH
• heterochromatin účinky léků   MeSH
• metylace DNA účinky léků   MeSH
• oprava DNA účinky léků   MeSH
• poškození DNA * účinky léků   MeSH
• RNA interference účinky léků   MeSH
• tandemové repetitivní sekvence účinky léků   MeSH
• umlčování genů * účinky léků   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 3-deazaneplanocin MeSH Prohlížeč
• adenosin MeSH
• azacytidin MeSH
• cytidin MeSH
• decitabin MeSH
• heterochromatin MeSH
• pyrimidin-2-one beta-ribofuranoside MeSH Prohlížeč

Syntheses of α-branched alkyl and aryl substituted 9-[2-(phosphonomethoxy)ethyl]purines from substituted 1,3-dioxolanes have been developed. Key synthetic precursors, α-substituted dialkyl [(2-hydroxyethoxy)methyl]phosphonates were prepared via Lewis acid mediated cleavage of 1,3-dioxolanes followed by reaction with dialkyl or trialkyl phosphites. The best preparative yields were achieved under conditions utilizing tin tetrachloride as Lewis acid and triisopropyl phosphite. Attachment of purine bases to dialkyl [(2-hydroxyethoxy)methyl]phosphonates was performed by Mitsunobu reaction. Final α-branched 9-[2-(phosphonomethoxy)ethyl]purines were tested for antiviral, cytostatic and antiparasitic activity, the latter one determined as inhibitory activity towards Plasmodium falciparum enzyme hypoxanthine-guanine-xanthine phosphoribosyltransfesase. In most cases biological activity was only marginal.

• Klíčová slova
• 1,3-dioxolanes, Acyclic nucleoside phosphonates, PEEG, PMEG, dialkyl phosphite, trialkyl phosphite,
• MeSH
• antiparazitární látky chemická syntéza   chemie   farmakologie   MeSH
• antivirové látky chemická syntéza   chemie   farmakologie   MeSH
• dioxolany chemie   MeSH
• DNA viry účinky léků   MeSH
• inhibitory enzymů chemická syntéza   chemie   farmakologie   MeSH
• lidé MeSH
• mikrobiální testy citlivosti MeSH
• molekulární struktura MeSH
• myši MeSH
• nádorové buněčné linie MeSH
• pentosyltransferasy antagonisté a inhibitory   metabolismus   MeSH
• Plasmodium falciparum účinky léků   enzymologie   MeSH
• puriny chemická syntéza   chemie   farmakologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antiparazitární látky MeSH
• antivirové látky MeSH
• dioxolany MeSH
• hypoxanthine-guanine-xanthine phosphoribosyltransferase MeSH Prohlížeč
• inhibitory enzymů MeSH
• pentosyltransferasy MeSH
• puriny MeSH

With respect to the strong antiviral activity of (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-azacytosine various types of its side chain fluorinated analogues were prepared. The title compound, (S)-1-[3-fluoro-2-(phosphonomethoxy)propyl]-5-azacytosine (FPMP-5-azaC) was synthesised by the condensation reaction of (S)-2-[(diisopropoxyphosphoryl)methoxy)-3-fluoropropyl p-toluenesulfonate with a sodium salt of 5-azacytosine followed by separation of appropriate N 1 and O 2 regioisomers and ester hydrolysis. Transformations of FPMP-5-azaC to its 5,6-dihydro-5-azacytosine counterpart, amino acid phosphoramidate prodrugs and systems with an annelated five-membered imidazole ring, i.e. imidazo [1,2-a][1,3,5]triazine derivatives were also carried out. 1-(2-Phosphonomethoxy-3,3,3-trifluoropropyl)-5-azacytosine was prepared from 5-azacytosine and trifluoromethyloxirane to form 1-(3,3,3-trifluoro-2-hydroxypropyl)-5-azacytosine which was treated with diisopropyl bromomethanephosphonate followed by deprotection of esters. Antiviral activity of all newly prepared compounds was studied. FPMP-5-azaC diisopropyl ester inhibited the replication of herpes viruses with EC50 values that were about three times higher than that of the reference anti-HCMV drug ganciclovir without displaying cytotoxicity.

• Klíčová slova
• 5-Azacytosine, Acyclic nucleoside phosphonates, Fluorinated nucleotides, Phosphonates, Prodrugs,
• Publikační typ
• časopisecké články MeSH