The role of 5-arylalkylamino- and 5-piperazino- moieties on the 7-aminopyrazolo[4,3-d]pyrimidine core in affecting adenosine A1 and A2A receptor affinity and selectivity profiles

New 7-amino-2-phenylpyrazolo[4,3-d]pyrimidine derivatives, substituted at the 5-position with aryl(alkyl)amino- and 4-substituted-piperazin-1-yl- moieties, were synthesized with the aim of targeting human (h) adenosine A1 and/or A2A receptor subtypes. On the whole, the novel derivatives 1-24 shared scarce or no affinities for the off-target hA2B and hA3 ARs. The 5-(4-hydroxyphenethylamino)- derivative 12 showed both good affinity (Ki = 150 nM) and the best selectivity for the hA2A AR while the 5-benzylamino-substituted 5 displayed the best combined hA2A (Ki = 123 nM) and A1 AR affinity (Ki = 25 nM). The 5-phenethylamino moiety (compound 6) achieved nanomolar affinity (Ki = 11 nM) and good selectivity for the hA1 AR. The 5-(N4-substituted-piperazin-1-yl) derivatives 15-24 bind the hA1 AR subtype with affinities falling in the high nanomolar range. A structure-based molecular modeling study was conducted to rationalize the experimental binding data from a molecular point of view using both molecular docking studies and Interaction Energy Fingerprints (IEFs) analysis.[Formula: see text]

Workload measurement for molecular genetics laboratory: A survey study

Genetic testing availability in the health care system is rapidly increasing, along with the diffusion of next-generation sequencing (NGS) into diagnostics. These issues make imperative the knowledge-drive optimization of testing in the clinical setting. Time estimations of wet laboratory procedure in Italian molecular laboratories offering genetic diagnosis were evaluated to provide data suitable to adjust efficiency and optimize health policies and costs. A survey was undertaken by the Italian Society of Human Genetics (SIGU). Forty-two laboratories participated. For most molecular techniques, the most time-consuming steps are those requiring an intensive manual intervention or in which the human bias can affect the global process time-performances. For NGS, for which the study surveyed also the interpretation time, the latter represented the step that requiring longer times. We report the first survey describing the hands-on times requested for different molecular diagnostics procedures, including NGS. The analysis of this survey suggests the need of some improvements to optimize some analytical processes, such as the implementation of laboratory information management systems to minimize manual procedures in pre-analytical steps which may affect accuracy that represents the major challenge to be faced in the future setting of molecular genetics laboratory

Pharmacological characterization of adenosine receptors in chronic inflammatory rheumatic diseases

L’artrite reumatoide, la spondilite anchilosante e l’artrite psoriasica sono malattie infiammatorie croniche, progressive e invalidanti che colpiscono le articolazioni provocando dolore e disabilità. I recettori dell’adenosina giocano un ruolo fondamentale nel meccanismo infiammatorio, in particolare l’attivazione dei sottotipi recettoriali A2A e A3 è spesso associata ad una riduzione dello stato infiammatorio. Il primo obiettivo di questo studio è stato quello di indagare il coinvolgimento dei recettori adenosinici nei pazienti affetti da artrite reumatoide all’esordio della patologia (non ancora in cura), artrite reumatoide, spondilite anchilosante ed artrite psoriasica. L’analisi dell’RNA messaggero (mRNA) e gli esperimenti di saturazione del binding hanno indicato una sovraespressione dei recettori A2A e A3 dell’adenosina nei linfociti ottenuti dai pazienti, comparati con soggetti di controllo sani. Gli agonisti dei recettori adenosinici A2A e A3 sono stati in grado di inibire l’attivazione di NF-κB, un complesso proteico funzionante come fattore di trascrizione. Inoltre hanno ridotto il rilascio di citochine pro infiammatorie, come ad esempio TNF-α, IL-1β e IL-6. Per di più l’attivazione dei sottotipi recettoriali A2A e A3 è stata in grado di mediare una riduzione delle metalloproteasi (MMP)-1 e MMP-3. L’effetto degli agonisti è stato annullato grazie alla somministrazione di antagonisti recettoriali selettivi, dimostrando così il diretto coinvolgimento di questi sottotipi recettoriali. Questi dati confermano l’implicazione dei recettori dell’adenosina nelle patologie reumatiche cronico degenerative evidenziando la possibilità di utilizzare i recettori A2A e A3 dell’adenosina come target terapeutici, con lo scopo di limitare la risposta infiammatoria spesso associata ad artrite reumatoide, spondilite anchilosante ed artrite psoriasica. Lo scopo del secondo capitolo di questa tesi, è stato quello di valutare la modulazione dei recettori A2A e A3 dell’adenosina nei pazienti affetti dalle patologie prese in esame nel primo capitolo, dopo diversi trattamenti farmacologici. Abbiamo indagato sulla densità e la funzionalità recettoriale nella progressione delle patologie attraverso uno studio longitudinale nei pazienti affetti da artrite reumatoide, spondilite anchilosante ed artrite psoriasica prima e dopo le terapie in uso, quali metotressato, agenti anti-TNFα o rituximab. I recettori A2A e A3 dell’adenosina sono stati analizzati attraverso esperimenti di saturazione del binding nei linfociti dei pazienti presi in esame, durante un periodo di ricerca della durata di 24 mesi. Nei linfociti ottenuti dai pazienti affetti da artrite reumatoide, la sovraespressione dei sottotipi recettoriali A2A e A3 dell’adenosina è stata gradualmente ridotta in funzione del tempo di trattamento. Questi risultati confermano il coinvolgimento dei recettori adenosinici A2A e A3 nella progressione delle patologie reumatiche cronico degenerative, sottolineando che gli agonisti dei recettori A2A e A3 dell’adenosina potrebbero rappresentare un’alternativa terapeutica per il trattamento dell’artrite reumatoide.Rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) are chronic inflammatory rheumatic diseases that affect joints, causing debilitating pain and disability. Adenosine receptors (ARs) play a key role in the mechanism of inflammation, and the activation of A2A and A3AR subtypes is often associated with a reduction of the inflammatory status. The first aim of this study was to investigate the involvement of ARs in patients suffering from early-RA (ERA), RA, AS and PsA. Messenger RNA (mRNA) analysis and saturation binding experiments indicated an upregulation of A2A and A3ARs in lymphocytes obtained from patients when compared with healthy subjects. A2A and A3AR agonists inhibited nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activation and reduced inflammatory cytokines release, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. Moreover, A2A and A3AR activation mediated a reduction of metalloproteinases (MMP)-1 and MMP-3. The effect of the agonists was abrogated by selective antagonists demonstrating the direct involvement of these receptor subtypes. These data confirmed the involvement of ARs in chronic autoimmune rheumatic diseases highlighting the possibility to exploit A2A and A3ARs as therapeutic targets, with the aim to limit the inflammatory responses usually associated with RA, AS and PsA. The purpose of the second chapter of this thesis, was to evaluate the modulation of A2A and A3ARs in patients suffering from RA, AS and PsA after different pharmacological treatments. We investigated A2A and A3AR density and functionality in pathologies progression by using a longitudinal study in RA, AS and PsA patients before and after methotrexate (MTX), anti-TNFa agents or rituximab treatments. A2A and A3ARs were analyzed by saturation binding assays in lymphocytes from patients throughout the 24-month study timeframe. In lymphocytes obtained from RA patients, the A2A and A3AR up-regulation was gradually reduced in function of the treatment time. Taken together, these data confirmed the involvement of A2A and A3ARs in chronic inflammatory rheumatic disease progression and highlighted that A2A and A3AR agonists could represent a physiological-like therapeutic alternative for RA treatment

Role and function of A2A and A3 adenosine receptors in patients with ankylosing spondylitis, psoriatic arthritis and rheumatoid arthritis

Rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA) are chronic inflammatory rheumatic diseases that affect joints, causing debilitating pain and disability. Adenosine receptors (ARs) play a key role in the mechanism of inflammation, and the activation of A2A and A3AR subtypes is often associated with a reduction of the inflammatory status. The aim of this study was to investigate the involvement of ARs in patients suffering from early-RA (ERA), RA, AS and PsA. Messenger RNA (mRNA) analysis and saturation binding experiments indicated an upregulation of A2A and A3ARs in lymphocytes obtained from patients when compared with healthy subjects. A2A and A3AR agonists inhibited nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) activation and reduced inflammatory cytokines release, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β and IL-6. Moreover, A2A and A3AR activation mediated a reduction of metalloproteinases (MMP)-1 and MMP-3. The effect of the agonists was abrogated by selective antagonists demonstrating the direct involvement of these receptor subtypes. Taken together, these data confirmed the involvement of ARs in chronic autoimmune rheumatic diseases highlighting the possibility to exploit A2A and A3ARs as therapeutic targets, with the aim to limit the inflammatory responses usually associated with RA, AS and PsA

A2A adenosine receptor upregulation correlates with disease activity in patients with systemic lupus erythematosus

BACKGROUND: Adenosine is a purine nucleoside implicated in the regulation of the innate and adaptive immune systems, acting through its interaction with four cell surface receptors: A1, A2A, A2B, and A3. There is intense interest in understanding how adenosine functions in health and during disease, but surprisingly little is known about the actual role of adenosine-mediated mechanisms in systemic lupus erythematosus (SLE). With this background, the aim of the present study was to test the hypothesis that dysregulation of A1, A2A, A2B, and A3 adenosine receptors (ARs) in lymphocytes of patients with SLE may be involved in the pathogenesis of the disease and to examine the correlations between the status of the ARs and the clinical parameters of SLE. METHODS: ARs were analyzed by performing saturation-binding assays, as well as messenger RNA and Western blot analysis, with lymphocytes of patients with SLE in comparison with healthy subjects. We tested the effect of A2AAR agonists in the nuclear factor kB (NF-kB) pathway and on the release of interferon (IFN)-α; tumor necrosis factor (TNF)-α; and interleukin (IL)-2, IL-6, IL-1β, and IL-10. RESULTS: In lymphocytes obtained from 80 patients with SLE, A2AARs were upregulated compared with those of 80 age-matched healthy control subjects, while A1, A2B, and A3 ARs were unchanged. A2AAR density was inversely correlated with Systemic Lupus Erythematosus Disease Activity Index 2000 score disease activity through time evaluated according to disease course patterns, serositis, hypocomplementemia, and anti-double-stranded DNA positivity. A2AAR activation inhibited the NF-kB activation pathway and diminished inflammatory cytokines (IFN-α, TNF-α, IL-2, IL-6, IL-1β), but it potentiated the release of anti-inflammatory IL-10. CONCLUSIONS: These data suggest the involvement of A2AARs in the complex pathogenetic network of SLE, acting as a modulator of the inflammatory process. It could represent a compensatory pathway to better counteract disease activity. A2AAR activation significantly reduced the release of proinflammatory cytokines while enhancing those with anti-inflammatory activity, suggesting a potential translational use of A2AAR agonists in SLE pharmacological treatment

Repeated dosing with NCX1404, a nitric oxide-donating pregabalin, re-establishes normal nociceptive responses in mice with streptozotocin-induced painful diabetic neuropathy

NCX1404 [(3S)-5-methyl-3-(((1-(4-(nitrooxy)butanoyloxy)ethoxy) carbonylamino) methyl)hexanoic acid] is a novel nitric oxide (NO)-donating pregabalin that is readily absorbed and processed in vivo to pregabalin and NO. We determined the antiallodynic response of NCX1404 after acute or after 7, 14, and 21 days of repeated daily oral dosing in mice with streptozotocin (STZ)-induced painful diabetic neuropathy (PDN). Pregabalin and its combination with the NO donor isosorbide mononitrate (ISMN) were used for comparison. The blood levels of pregabalin and nitrites, used as surrogate marker of NO release, after NCX1404 or pregabalin dosing were monitored in parallel experiments using liquid chromatography with tandem mass spectrometry (LC-MS/MS). NCX1404 and pregabalin resulted in similar pregabalin levels as it was their antiallodynic activity after acute dosing in STZ mice. However, NCX1404 resulted in disease-modifying properties when administered daily for 21 days, as indicated by the time- and dose-dependent reversal of STZ-induced mechanical allodynia (paw withdrawal threshold [PWT]Veh-21d = 1.3 v 0.15 g for vehicle; PWTNCX1404-21d = 1.4 ± 0.5 g, 2.9 ± 0.2 g∗ and 4.1 ± 0.2 g∗, respectively for 19, 63, and 190 μmol/kg, oral gavage [PO] of NCX1404; ∗P, 0.05 versus vehicle). This effect was not shared by pregabalin at equimolar doses (190 μmol/kg, PO, PWTPregab-21d = 1.4 ± 0.1 g∗, ∗P < 0.05 versus equimolar NCX1404). In addition, the NO donor ISMN (52.3 μmol/kg, PO) alone or combined with pregabalin (63 μmol/kg) was active at 7 days (PWTVeh-7d= 1.7 ± 0.16 g; PWTISMN-7d = 3.9 ± 0.34 g∗; PWTPregab-7d = 1.3 ± 0.07 g; PWTISMN+pregab-7d = 3.8 ± 0.29 g∗; ∗P, 0.05) but not at later time points. The long-term effect of NCX1404 was independent of residual drug exposure and lasted for several days after the treatment was stopped. In summary, like pregabalin, NCX1404 is an effective antiallodynic agent. Differently from pregabalin, repeated dosing of NCX1404 re-established normal nociceptive responses in STZ-induced PDN in mice

Pulsed Electromagnetic Field Exposure Reduces Hypoxia and Inflammation Damage in Neuron-Like and Microglial Cells

In the present study, the effect of low-frequency, low-energy pulsed electromagnetic fields (PEMFs) has been investigated by using different cell lines derived from neuron-like cells and microglial cells. In particular, the primary aim was to evaluate the effect of PEMF exposure in inflammation- and hypoxia-induced injury in two different neuronal cell models, the human neuroblastoma-derived SH-SY5Y cells and rat pheochromocytoma PC12 cells and in N9 microglial cells. In neuron-like cells, live/dead and apoptosis assays were performed in hypoxia conditions from 2 to 48 h. Interestingly, PEMF exposure counteracted hypoxia damage significantly reducing cell death and apoptosis. In the same cell lines, PEMFs inhibited the activation of the hypoxia-inducible factor 1α (HIF-1α), the master transcriptional regulator of cellular response to hypoxia. The effect of PEMF exposure on reactive oxygen species (ROS) production in both neuron-like and microglial cells was investigated considering their key role in ischemic injury. PEMFs significantly decreased hypoxia-induced ROS generation in PC12, SH-SY5Y, and N9 cells after 24 or 48 h of incubation. Moreover, PEMFs were able to reduce some of the most well-known pro-inflammatory cytokines such as tumor necrosis factor–α (TNF-α), interleukin (IL)-1β, IL-6, and IL-8 release in N9 microglial cells stimulated with different concentrations of LPS for 24 or 48 h of incubation time. These results show a protective effect of PEMFs on hypoxia damage in neuron-like cells and an anti-inflammatory effect in microglial cells suggesting that PEMFs could represent a potential therapeutic approach in cerebral ischemic conditions. J. Cell. Physiol. 232: 1200–1208, 2017. © 2016 Wiley Periodicals, Inc

Design, Synthesis, and Pharmacological Characterization of 2-(2-Furanyl)thiazolo[5,4-d]pyrimidine-5,7-diamine Derivatives: New Highly Potent A2A Adenosine Receptor Inverse Agonists with Antinociceptive Activity

In this study, we describe the design and synthesis of new N5-substituted-2-(2-furanyl) thiazolo[5,4-d]pyrimidine-5,7-diamines (2-18) and their pharmacological characterization as A2A adenosine receptor (AR) antagonists by using in vitro and in vivo assays. In competition binding experiments two derivatives (13 and 14) emerged as outstanding ligands showing two different affinity values (KH and KL) for the hA2A receptor with the high affinity KH value in the femtomolar range. The in vitro functional activity assays, performed by using cyclic AMP experiments, assessed that they behave as potent inverse agonists at the hA2A AR. Compounds 13 and 14 were evaluated for their antinociceptive activity in acute experimental models of pain showing an effect equal to or greater than that of morphine. Overall, these novel inverse agonists might represent potential drug candidates for an alternative approach to the management of pain