You're viewing our updated article page. If you need more time to adjust, you can return to the old layout.

MINI REVIEW article

Front. Neurosci., 16 July 2021

Sec. Neuropharmacology

Volume 15 - 2021 | https://doi.org/10.3389/fnins.2021.702581

Adenosine A2A Receptors as Biomarkers of Brain Diseases

  • 1. CNC—Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal

  • 2. Faculty of Medicine, University of Coimbra, Coimbra, Portugal

Article metrics

View details

29

Citations

5,5k

Views

2,6k

Downloads

Abstract

Extracellular adenosine is produced with increased metabolic activity or stress, acting as a paracrine signal of cellular effort. Adenosine receptors are most abundant in the brain, where adenosine acts through inhibitory A1 receptors to decrease activity/noise and through facilitatory A2A receptors (A2AR) to promote plastic changes in physiological conditions. By bolstering glutamate excitotoxicity and neuroinflammation, A2AR also contribute to synaptic and neuronal damage, as heralded by the neuroprotection afforded by the genetic or pharmacological blockade of A2AR in animal models of ischemia, traumatic brain injury, convulsions/epilepsy, repeated stress or Alzheimer’s or Parkinson’s diseases. A2AR overfunction is not only necessary for the expression of brain damage but is actually sufficient to trigger brain dysfunction in the absence of brain insults or other disease triggers. Furthermore, A2AR overfunction seems to be an early event in the demise of brain diseases, which involves an increased formation of ATP-derived adenosine and an up-regulation of A2AR. This prompts the novel hypothesis that the evaluation of A2AR density in afflicted brain circuits may become an important biomarker of susceptibility and evolution of brain diseases once faithful PET ligands are optimized. Additional relevant biomarkers would be measuring the extracellular ATP and/or adenosine levels with selective dyes, to identify stressed regions in the brain. A2AR display several polymorphisms in humans and preliminary studies have associated different A2AR polymorphisms with altered morphofunctional brain endpoints associated with neuropsychiatric diseases. This further prompts the interest in exploiting A2AR polymorphic analysis as an ancillary biomarker of susceptibility/evolution of brain diseases.

Introduction

The increased use of intracellular ATP, either because of increased workload or need to cope with stressful conditions, is a main source of increased extracellular levels of adenosine, which generally acts as a paracrine allostatic regulator by locally decreasing metabolism through inhibitory A1 receptors (A1R) and increasing metabolic supply through A2AR (Agostinho et al., 2020). Adenosine receptors are most abundant in the brain, where adenosine fulfills a role as neuromodulator apart from its general paracrine allostatic role: post-synaptic as well as astrocytic integrative activity are major contributors of an adenosine tone acting through inhibitory A1 receptors to decrease activity/noise in excitatory synapses; ATP release, characteristic of increased firing rate conditions associated with synaptic plasticity, is the major source of a second pool of synaptic extracellular adenosine selectively activating facilitatory A2A receptors (A2AR) to promote synaptic plastic changes in physiological conditions (Cunha, 2016). However, ATP is also a general danger signal in the brain (Rodrigues et al., 2015), acting through a variety of ATP/ADP-activated P2 receptors to re-shape the function of astrocytes and microglia to cope with potential threats (Agostinho et al., 2020). Such threats also require adaptive plastic changes in neuronal circuits, which may explain the increased extracellular formation of ATP-derived adenosine by ecto-nucleotidases, with a burst of its rate-limiting step—ecto-5′-nucleotidase or CD73 (Cunha, 2001)—under noxious brain conditions to sustain an overfunction of A2AR that contributes to synaptotoxicity and neurotoxicity in different brain diseases (Cunha, 2016).

Adenosine A2A Receptors in Brain Diseases

Upon acute brain injury, probably best exemplified by an ischemic brain stroke, concurrent pharmacological and genetic evidence show that A2AR blockade affords a robust neuroprotection (reviewed in Chen and Pedata, 2008). In parallel, ischemia is accompanied by ATP release (Melani et al., 2005) and up-regulation of CD73 (Braun et al., 1997), thus increasing the formation of extracellular ATP-derived adenosine (Koos et al., 1997; Chu et al., 2014). Likewise, seizure-like activity characteristic of epileptic conditions triggers a neurodegeneration that is critically controlled by pharmacological or genetic A2AR blockade (Canas et al., 2018). Seizure activity also increases ATP release (Wieraszko and Seyfried, 1989) and up-regulates CD73 (e.g., Schoen et al., 1999; Rebola et al., 2003), increasing the contribution of extracellular ATP-derived adenosine formation to overactivate A2AR (reviewed in Tescarollo et al., 2020). A2AR blockade also attenuates brain damage following traumatic brain injury (TBI) (e.g., Li et al., 2009); TBI also bolsters the release of ATP (Faroqi et al., 2021) and CD73 levels (Zheng et al., 2020), although the contribution of extracellular ATP-derived adenosine has not yet been tested in TBI.

Overall, this evidence is compatible with an increase of extracellular adenosine, namely extracellular ATP-derived adenosine, leading to an overactivation of A2AR that contributes for brain dysfunction upon acute brain injury. A similar scenario seems to occur in chronic brain conditions. Thus, the pharmacological or genetic blockade of A2AR affords a consistent neuroprotection in animal models of Alzheimer’s disease (AD) (e.g., Canas et al., 2009; Laurent et al., 2016; Viana da Silva et al., 2016), Parkinson’s disease (PD) (reviewed in Schwarzschild et al., 2006)—where A2AR antagonists were approved by the US-FDA as novel anti-Parkinsonian drugs (Chen and Cunha, 2020), repeated stress/depression (Batalha et al., 2013; Kaster et al., 2015; Padilla et al., 2018), Machado-Joseph disease (Gonçalves et al., 2013), amyotrophic lateral sclerosis (ALS) (Ng et al., 2015; Rei et al., 2020; Seven et al., 2020), Angelman syndrome (Moreira-de-Sá et al., 2020, 2021), or glaucoma-like disorders (Madeira et al., 2015). Most of these chronic neuropsychiatric conditions are also associated with increased release of ATP, as occurs in animal models of AD (Gonçalves et al., 2019), PD (Carmo et al., 2019; Meng et al., 2019) or as concluded by the anti-depressant effects of P2 receptor antagonists (Ribeiro et al., 2019; but see Cao et al., 2013). Moreover, there is an increased contribution of extracellular ATP-derived adenosine for A2AR overactivation in chronic brain diseases, as best heralded by the observation that CD73 knockout mice phenocopy A2AR knockout mice (Augusto et al., 2013; Carmo et al., 2019; Gonçalves et al., 2019).

A2AR overactivation is not only necessary, but actually sufficient to trigger brain dysfunction, as concluded from the observation that the pharmacological overactivation of A2AR (Pagnussat et al., 2015), the optogenetic activation of A2AR transducing system (Li et al., 2015) or the over-expression of A2AR in the hippocampus (Coelho et al., 2014; Carvalho et al., 2019; Temido-Ferreira et al., 2020) are sufficient to trigger or aggravate brain dysfunction. Notably, A2AR overfunction seems to be an early event in different brain disorders (reviewed in Cunha, 2016), although A2AR antagonists seem to maintain their neuroprotective profile after the establishment of symptoms (e.g., Kaster et al., 2015; Faivre et al., 2018; Orr et al., 2018; Silva et al., 2018).

The tight association between increased release of ATP and its extracellular catabolism to overactivate A2AR as part of the expression of neuronal dysfunction at the onset and throughout the evolution of several brain diseases prompts exploiting this danger signaling pathway as new biomarkers to identify dysfunctional brain circuits in brain diseases. Although the tools are yet to developed, it may be promising to devise soluble sensors to detect altered levels of extracellular ATP to allow an in vivo estimate of brain circuits undergoing a particular purinergic pressure and, consequently, are at risk of undergoing dysfunction. An alternative could be the development of PET ligands (not yet available) to assess the density of CD73, which is paramount to link ATP upsurge with the selective overactivation of A2AR; CD73 seems to be consistently up-regulated upon brain stressful conditions and may be a selective biomarker of glia and synapses undergoing adaptive processes (Schoen and Kreutzberg, 1997).

Up-Regulation of Adenosine A2A Receptors in Brain Diseases

The A2AR overactivation associated with brain dysfunction and disease is not only sustained by an increased bioavailability of the trigger of A2AR—ATP-derived extracellular adenosine—but also involves an up-regulation of A2AR in the afflicted brain areas (reviewed in Cunha, 2016). Indeed, an increased density of cortical A2AR has been reported in animal models of epilepsy (Rebola et al., 2005; Cognato et al., 2010; Canas et al., 2018; Crespo et al., 2018), Rasmussen’s encephalopathy (He et al., 2020), TBI (Zhao et al., 2017), AD (Espinosa et al., 2013; Viana da Silva et al., 2016; Silva et al., 2018), Lyme neuroborreliosis (Smith et al., 2014), ALS (Seven et al., 2020), or chronic stress/depression (Kaster et al., 2015; Machado et al., 2017), as well as in the diseased human brain (Albasanz et al., 2008; Temido-Ferreira et al., 2020). Likewise, A2AR levels are also increased in the cerebellum of Machado-Joseph’s ataxic mice (Gonçalves et al., 2013) and in the amygdala or fear-conditioned mice (Simões et al., 2016). A2AR up-regulation is in fact an upsurge since it occurs shortly (within hours) after abnormal neuronal function (i.e., convulsions; Canas et al., 2018), but it gradually increases with aggravation of brain dysfunction (Temido-Ferreira et al., 2020). A2AR up-regulation mostly occurs in synapses, in accordance with the involvement of synaptic alterations at the onset of most brain diseases (e.g., Rebola et al., 2005; Kaster et al., 2015; Viana da Silva et al., 2016; Canas et al., 2018), but is also observed in glia cells in the progression of chronic brain diseases (Matos et al., 2012; Orr et al., 2015; Barros-Barbosa et al., 2016; Patodia et al., 2020). It is still unclear if this A2AR up-regulation only involves an increased readout of A2AR mRNAs (Canas et al., 2018) or also involves an overexpression of A2AR mRNA, which has been reported in the dysfunctional or diseased brain (e.g., Costenla et al., 2011; Espinosa et al., 2013; Hu et al., 2016; Dias et al., 2021). In fact, the triggers and mechanisms of this A2AR up-regulation in the diseased brain are essentially unknown. The A2AR gene in both rodents and humans has a complex promoter region and can give raise to multiple transcripts (Peterfreund et al., 1996; Lee et al., 2003a; Yu et al., 2004; Kreth et al., 2008; Huin et al., 2019). Although multiple controllers of the A2AR gene have been proposed, such as methylation patterns of the promoter (Falconi et al., 2019; Micioni Di Bonaventura et al., 2019), transcription factors ZBP-89 and Yin Yang-1 (Buira et al., 2010), microRNAs (e.g., Heyn et al., 2012; Villar-Menéndez et al., 2014; Zhao et al., 2015; Tian et al., 2016), NFk-B (Morello et al., 2006), cAMP-response element-binding protein (Chiang et al., 2005), hypoxia inducible factor-2α (Ahmad et al., 2009; Brown et al., 2011), AP1 transcription factor (Kobayashi and Millhorn, 1999; Lee et al., 2014), or nuclear factor 1 (Lee et al., 2003b), the regulation of the relative expression of these transcripts is largely unknown (Yu et al., 2004; Huin et al., 2019) and little is also known about the relative stability of the different mRNA transcripts. This is certainly an area of research that might open new avenues to design neuroprotective strategies linked to A2AR.

The association of A2AR up-regulation with brain diseases offers another promising opportunity to develop informative biomarkers of the susceptibility and/or evolution of different brain diseases once PET ligands are optimized to detect extra-striatal A2AR. In fact, A2AR throughout the brain are most abundant in the striatum (reviewed in Svenningsson et al., 1999) and the available PET ligands have been optimized to detect striatal A2AR (e.g., Mishina et al., 2011; Ishibashi et al., 2018); however, this population of A2AR has a different pharmacology (Orrú et al., 2011; Cunha, 2016), a different adaptive profile (Cunha et al., 1995) and a different role in most brain conditions (Shen et al., 2008, 2013; Yu et al., 2008; Wei et al., 2014). Thus, it is likely that the currently available PET ligands might not be useful to assess modifications of extra-striatal A2AR. New cortical A2AR-directed PET ligands need to be designed based on the particular properties and interacting partners of cortical A2AR (reviewed in Franco et al., 2020) to allow an in vivo detection of A2AR upsurge as potential general biomarkers of brain dysfunction (Sun et al., 2020).

A2AR are not only located in the brain, but are also present in several peripheral tissues, namely in different blood cells such as leukocytes and platelets (reviewed in Gessi et al., 2000). Based on the association of brain diseases with A2AR up-regulation in afflicted brain regions, several studies explored if A2AR in blood cells could be biomarkers of brain diseases, such as AD (Arosio et al., 2010, 2016; Merighi et al., 2021), PD (Falconi et al., 2019), or ALS (Vincenzi et al., 2013). However, only the understanding of the mechanisms underlying A2AR up-regulation in brain diseases will allow providing a rationale (or lack of thereof) to consider alterations of the density of peripheral A2AR as valid readouts of altered A2AR density that occurs selectively in afflicted brain circuits in the diseased brain.

Polymorphisms of Adenosine A2A Receptors and Brain Diseases

The gene encoding human A2AR (ADORA2A gene) harbors several single nucleotide polymorphisms (SPNs), which have been associated to an altered susceptibility to several neuropsychiatric and neurodegenerative disorders (Huin et al., 2019). In fact, as listed in Tables 1A,B, naturally occurring variabilities in the ADORA2A gene collectively influence predisposition risk and even age of onset for several CNS disorders as well as individual susceptibility to the anxiogenic and sleep-related consequences of caffeine. Although, it is still unknown if the different A2AR polymorphisms are associated with a different expression, subcellular location, trafficking, heteromerization or pharmacological properties of A2AR, the relation between A2AR polymorphisms and the susceptibility and age of onset of brain dysfunction prompts the interest in exploiting A2AR polymorphic analysis as an ancillary biomarker of susceptibility/evolution of brain diseases.

TABLE 1

(A) SNP Type/Position Risk allele/Genotype Associated CNS Disorder References
rs5751876 Exon 2 TT Huntington’s disease (significant variability in age of onset) Taherzadeh-Fard et al., 2010
T Susceptibility locus for Panic Disorder and Agoraphobia Deckert et al., 1998; Hamilton et al., 2004; Domschke et al., 2012
T Prevalent in Gilles de la Tourette syndrome (GTS) patients Janik et al., 2015
rs2298383 5′ UTR TT Huntington’s disease (significant variability in age of onset) Taherzadeh-Fard et al., 2010
CT Higher predisposition for Childhood Epilepsy (CE) Fan et al., 2020
CC Greater risk for CE patients to develop comorbid neurologic disorders Fan et al., 2020
CC/CT Increased risk of Depression, Attention Deficits and Sleep-disturbances Oliveira et al., 2019
CC Possible risk factor for Schizophrenia Miao et al., 2019
rs2236624 Intron 4 CC Associated with Autism Spectrum Disorders symptom severity Freitag et al., 2010
rs71651683 5′ UTR T Inverse association with the likelihood to develop Parkinson’s disease (∼49%) Popat et al., 2011
rs5996696 Promoter variant region C Inverse association with the likelihood to develop Parkinson’s disease (∼30%) Popat et al., 2011
rs2298383, rs5751876, rs35320474, and rs4822492 5′ UTR, Exon 2, Exon 4, and 3′ UTR C, T, deletion and C, respectively, (Haplotype A) Predisposition of children to develop Acute Encephalopathy with biphasic seizures and late reduced diffusion (AESD) Shinohara et al., 2013

(B) SNP Type/Position Risk allele/Genotype Physiological Response to Stimuli References

rs5751876 Exon 2 TT Significant enhancement of caffeine-induced anxiety Alsene et al., 2003; Childs et al., 2008
TT Associated with an overall lower caffeine intake and a prospective lesser vulnerability to caffeine dependence Cornelis et al., 2007
TT Highest startle magnitudes upon caffeine administration in response to unpleasant pictures (maladaptive emotional processing) Domschke et al., 2012
TT Associated with an ergogenic beneficial effect upon caffeine consumption Loy et al., 2015
TT Higher anxiogenic response susceptibility to caffeine ingestion in usual non-consumers or low consumers (<40 mg per day), but no significant correlation with habitual caffeine intake Rogers et al., 2010
C Sleep disturbances (and insomnia) triggered by caffeine intake, higher β-activity in non-REM sleep Rétey et al., 2007
T Lower total sleep time in habitual low caffeine consumers Erblang et al., 2019
T Increased sleep latency associated with caffeine consumption, lower percentage of N3 sleep stage Nunes et al., 2017
rs2298383 5′ UTR CC Significant enhancement of caffeine-induced anxiety Childs et al., 2008
C Lower total sleep time in habitual low caffeine consumers Erblang et al., 2019
rs4822492 3′ UTR CC Significant enhancement of caffeine-induced anxiety Childs et al., 2008
CC Lower total sleep time in habitual low caffeine consumers Erblang et al., 2019
rs3761422 5′ UTR TT Greater increase in anxiety upon caffeine ingestion in habitual non-consumers or low consumers (<40 mg per day) Rogers et al., 2010
T Lower total sleep time in habitual low caffeine consumers Erblang et al., 2019

Summary of the reported associations between known polymorphic variants of the human adenosine A2A receptor gene (ADORA2A) and different response susceptibility to either pathological threats (A) or distinct physiological responses to external stimulus (B).

Discussion

A2AR overfunction is necessary and actually sufficient for the expression of neuronal dysfunction upon brain diseases. In particular, A2AR overfunction associated with aberrant synaptic plasticity and synaptotoxicity seems to be associated with the onset of symptoms of brain diseases. However, some of these symptoms are comorbidities of other brain diseases, associated with their aggravation, which often involves a spreading of neuroinflammation, also known to be controlled by A2AR. Thus, it is also likely that A2AR overfunction might be also associated with the evolution of brain diseases. These neuropathological roles of A2AR prompts considering the exploitation of this system as candidate biomarkers of the susceptibility and evolution of brain diseases. The development of PET ligand with adequate signal-to-noise ratio and selectivity to detect the relevant extra-striatal A2AR may allow a minimally invasive assessment of A2AR in different brain regions. This may be complemented by the definition of A2AR polymorphisms as an ancillary biomarker for the susceptibility and evolution of brain diseases, which still requires a firm establishment of structural-functional relationships between A2AR polymorphisms and brain dysfunction. Finally, the future development of PET-based sensors of extracellular ATP and/or adenosine may well be of additional interest as a biomarker of the status of brain diseases to be used in complement of other available methods.

Statements

Author contributions

All authors contribute to the organization and writing of the review.

Funding

This study was supported by La Caixa Foundation (LCF/PR/HP17/52190001), Centro 2020 (CENTRO-01-0145-FEDER-000008:BrainHealth 2020 and CENTRO-01-0246-FEDER-000010), and FCT (POCI-01-0145-FEDER-03127 and UIDB/04539/2020).

Conflict of interest

RC is a scientific consultant for the Institute for Scientific Information on Coffee. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

References

  • 1

    Agostinho P. Madeira D. Dias L. Simões A. P. Cunha R. A. Canas P. M. (2020). Purinergic signaling orchestrating neuron-glia communication.Pharmacol. Res.162:105253. 10.1016/j.phrs.2020.105253

  • 2

    Ahmad A. Ahmad S. Glover L. Miller S. M. Shannon J. M. Guo X. et al (2009). Adenosine A2A receptor is a unique angiogenic target of HIF-2alpha in pulmonary endothelial cells.Proc. Natl. Acad. Sci. USA1061068410689. 10.1073/pnas.0901326106

  • 3

    Albasanz J. L. Perez S. Barrachina M. Ferrer I. Martín M. (2008). Up-regulation of adenosine receptors in the frontal cortex in Alzheimer’s disease.Brain Pathol.18211219. 10.1111/j.1750-3639.2007.00112.x

  • 4

    Alsene K. Deckert J. Sand P. de Wit H. (2003). Association between A2A receptor gene polymorphisms and caffeine-induced anxiety.Neuropsychopharmacology2816941702. 10.1038/sj.npp.1300232

  • 5

    Arosio B. Casati M. Gussago C. Ferri E. Abbate C. Scortichini V. et al (2016). Adenosine type A2A receptor in peripheral cell from patients with Alzheimer’s disease, vascular dementia, and idiopathic normal pressure hydrocephalus: a new/old potential target.J. Alzheimers. Dis.54417425. 10.3233/JAD-160324

  • 6

    Arosio B. Viazzoli C. Mastronardi L. Bilotta C. Vergani C. Bergamaschini L. (2010). Adenosine A2A receptor expression in peripheral blood mononuclear cells of patients with mild cognitive impairment.J. Alzheimers. Dis.20991996. 10.3233/JAD-2010-090814

  • 7

    Augusto E. Matos M. Sevigny J. El-Tayeb A. Bynoe M. S. Müller C. E. et al (2013). Ecto-5′-nucleotidase (CD73)-mediated formation of adenosine is critical for the striatal adenosine A2A receptor functions.J. Neurosci.331139011399. 10.1523/JNEUROSCI.5817-12.2013

  • 8

    Barros-Barbosa A. R. Ferreirinha F. Oliveira A. Mendes M. Lobo M. G. Santos A. et al (2016). Adenosine A2A receptor and ecto-5′-nucleotidase/CD73 are upregulated in hippocampal astrocytes of human patients with mesial temporal lobe epilepsy (MTLE).Purinergic Signal.12719734. 10.1007/s11302-016-9535-2

  • 9

    Batalha V. L. Pego J. M. Fontinha B. M. Costenla A. R. Valadas J. S. Baqi Y. et al (2013). Adenosine A2A receptor blockade reverts hippocampal stress-induced deficits and restores corticosterone circadian oscillation.Mol. Psychiatry18320331. 10.1038/mp.2012.8

  • 10

    Braun N. Lenz C. Gillardon F. Zimmermann M. Zimmermann H. (1997). Focal cerebral ischemia enhances glial expression of ecto-5′-nucleotidase.Brain Res.766213226. 10.1016/s0006-8993(97)00559-3

  • 11

    Brown S. T. Reyes E. P. Nurse C. A. (2011). Chronic hypoxia upregulates adenosine 2A receptor expression in chromaffin cells via hypoxia inducible factor-2alpha: role in modulating secretion.Biochem. Biophys. Res. Commun.412466472. 10.1016/j.bbrc.2011.07.122

  • 12

    Buira S. P. Dentesano G. Albasanz J. L. Moreno J. Martín M. Ferrer I. et al (2010). DNA methylation and Yin Yang-1 repress adenosine A2A receptor levels in human brain.J. Neurochem.115283295. 10.1111/j.1471-4159.2010.06928.x

  • 13

    Canas P. M. Porciúncula L. O. Cunha G. M. Silva C. G. Machado N. J. Oliveira J. M. et al (2009). Adenosine A2A receptor blockade prevents synaptotoxicity and memory dysfunction caused by beta-amyloid peptides via p38 mitogen-activated protein kinase pathway.J. Neurosci.291474114751. 10.1523/jneurosci.3728-09.2009

  • 14

    Canas P. M. Porciúncula L. O. Simões A. P. Augusto E. Silva H. B. Machado N. J. et al (2018). Neuronal adenosine A2A receptors are critical mediators of neurodegeneration triggered by convulsions.eNeuro5:ENEURO.0385-18.2018. 10.1523/ENEURO.0385-18.2018

  • 15

    Cao X. Li L. P. Wang Q. Wu Q. Hu H. H. Zhang M. et al (2013). Astrocyte-derived ATP modulates depressive-like behaviors.Nat. Med.19773777. 10.1038/nm.3162

  • 16

    Carmo M. Gonçalves F. Q. Canas P. M. Oses J. P. Fernandes F. D. Duarte F. V. et al (2019). Enhanced ATP release and CD73-mediated adenosine formation sustain adenosine A2A receptor over-activation in a rat model of Parkinson’s disease.Br. J. Pharmacol.17636663680. 10.1111/bph.14771

  • 17

    Carvalho K. Faivre E. Pietrowski M. J. Marques X. Gomez-Murcia V. Deleau A. et al (2019). Exacerbation of C1q dysregulation, synaptic loss and memory deficits in tau pathology linked to neuronal adenosine A2A receptor.Brain14236363654. 10.1093/brain/awz288

  • 18

    Chen J. F. Pedata F. (2008). Modulation of ischemic brain injury and neuroinflammation by adenosine A2A receptors.Curr. Pharm. Des.1414901499. 10.2174/138161208784480126

  • 19

    Chen J. Cunha R. A. (2020). The belated US FDA approval of the adenosine A2A receptor antagonist istradefylline for treatment of Parkinson’s disease.Purinergic Signal.16167174. 10.1007/s11302-020-09694-2

  • 20

    Chiang M. C. Lee Y. C. Huang C. L. Chern Y. (2005). cAMP-response element-binding protein contributes to suppression of the A2A adenosine receptor promoter by mutant Huntingtin with expanded polyglutamine residues.J. Biol. Chem.2801433114340. 10.1074/jbc.M413279200

  • 21

    Childs E. Hohoff C. Deckert J. Xu K. Badner J. de Wit H. (2008). Association between ADORA2A and DRD2 polymorphisms and caffeine-induced anxiety.Neuropsychopharmacology3327912800. 10.1038/npp.2008.17

  • 22

    Chu S. Xiong W. Parkinson F. E. (2014). Effect of ecto-5′-nucleotidase (eN) in astrocytes on adenosine and inosine formation.Purinergic Signal.10603609. 10.1007/s11302-014-9421-8

  • 23

    Coelho J. E. Alves P. Canas P. M. Valadas J. S. Shmidt T. Batalha V. L. et al (2014). Overexpression of adenosine A2A receptors in rats: effects on depression, locomotion, and anxiety.Front. Psychiatry5:67. 10.3389/fpsyt.2014.00067

  • 24

    Cognato G. P. Agostinho P. M. Hockemeyer J. Müller C. E. Souza D. O. Cunha R. A. (2010). Caffeine and an adenosine A2A receptor antagonist prevent memory impairment and synaptotoxicity in adult rats triggered by a convulsive episode in early life.J. Neurochem.112453462. 10.1111/j.1471-4159.2009.06465.x

  • 25

    Cornelis M. C. El-Sohemy A. Campos H. (2007). Genetic polymorphism of the adenosine A2A receptor is associated with habitual caffeine consumption.Am. J. Clin. Nutr.86240244. 10.1093/ajcn/86.1.240

  • 26

    Costenla A. R. Diógenes M. J. Canas P. M. Rodrigues R. J. Nogueira C. Maroco J. et al (2011). Enhanced role of adenosine A2A receptors in the modulation of LTP in the rat hippocampus upon ageing.Eur. J. Neurosci.341221. 10.1111/j.1460-9568.2011.07719.x

  • 27

    Crespo M. León-Navarro D. A. Martín M. (2018). Early-life hyperthermic seizures upregulate adenosine A2A receptors in the cortex and promote depressive-like behavior in adult rats.Epilepsy Behav.86173178. 10.1016/j.yebeh.2018.06.048

  • 28

    Cunha R. A. (2001). Regulation of the ecto-nucleotidase pathway in rat hippocampal nerve terminals.Neurochem. Res.26979991. 10.1023/a:1012392719601

  • 29

    Cunha R. A. (2016). How does adenosine control neuronal dysfunction and neurodegeneration?J. Neurochem.13910191055. 10.1111/jnc.13724

  • 30

    Cunha R. A. Constantino M. C. Sebastião A. M. Ribeiro J. A. (1995). Modification of A1 and A2A adenosine receptor binding in aged striatum, hippocampus and cortex of the rat.Neuroreport615831588. 10.1097/00001756-199507310-00029

  • 31

    Deckert J. Nöthen M. M. Franke P. Delmo C. Fritze J. Knapp M. et al (1998). Systematic mutation screening and association study of the A1 and A2A adenosine receptor genes in panic disorder suggest a contribution of the A2A gene to the development of disease.Mol. Psychiatry38185. 10.1038/sj.mp.4000345

  • 32

    Dias L. Lopes C. R. Gonçalves F. Q. Nunes A. Pochmann D. Machado N. J. et al (2021). Crosstalk between ATP-P2X7 and adenosine A2A receptors controlling neuroinflammation in rats subject to repeated restraint stress.Front. Cell. Neurosci.15:639322. 10.3389/fncel.2021.639322

  • 33

    Domschke K. Gajewska A. Winter B. Herrmann M. J. Warrings B. Muhlberger A. et al (2012). ADORA2A Gene variation, caffeine, and emotional processing: a multi-level interaction on startle reflex.Neuropsychopharmacology37759769. 10.1038/npp.2011.253

  • 34

    Erblang M. Drogou C. Gomez-Merino D. Metlaine A. Boland A. Deleuze J. F. et al (2019). The impact of genetic variations in ADORA2A in the association between caffeine consumption and sleep.Genes10:1012. 10.3390/genes10121021

  • 35

    Espinosa J. Rocha A. Nunes F. Costa M. S. Schein V. Kazlauckas V. et al (2013). Caffeine consumption prevents memory impairment, neuronal damage, and adenosine A2A receptors upregulation in the hippocampus of a rat model of sporadic dementia.J. Alzheimers. Dis.34509518. 10.3233/JAD-111982

  • 36

    Faivre E. Coelho J. E. Zornbach K. Malik E. Baqi Y. Schneider M. et al (2018). Beneficial effect of a selective adenosine A2A receptor antagonist in the APPswe/PS1dE9 mouse model of Alzheimer’s disease.Front. Mol. Neurosci.11:235. 10.3389/fnmol.2018.00235

  • 37

    Falconi A. Bonito-Oliva A. Di Bartolomeo M. Massimini M. Fattapposta F. Locuratolo N. et al (2019). On the role of adenosine A2A receptor gene transcriptional regulation in Parkinson’s disease.Front. Neurosci.13:683. 10.3389/fnins.2019.00683

  • 38

    Fan X. Chen Y. Li W. Xia H. Liu B. Guo H. et al (2020). Genetic polymorphism of ADORA2A is associated with the risk of epilepsy and predisposition to neurologic comorbidity in Chinese southern children.Front. Neurosci.14:590605. 10.3389/fnins.2020.590605

  • 39

    Faroqi A. H. Lim M. J. Kee E. C. Lee J. H. Burgess J. D. Chen R. et al (2021). In vivo detection of extracellular adenosine triphosphate in a mouse model of traumatic brain injury.J. Neurotrauma38655664. 10.1089/neu.2020.7226

  • 40

    Franco R. Rivas-Santisteban R. Reyes-Resina I. Navarro G. (2020). The old and new visions of biased agonism through the prism of adenosine receptor signaling and receptor/receptor and receptor/protein interactions.Front. Pharmacol.11:628601. 10.3389/fphar.2020.628601

  • 41

    Freitag C. M. Agelopoulos K. Huy E. Rothermundt M. Krakowitzky P. Meyer J. et al (2010). Adenosine A2A receptor gene ADORA2A variants may increase autistic symptoms and anxiety in autism spectrum disorder.Eur. Child Adolesc. Psychiatry196774. 10.1007/s00787-009-0043-6

  • 42

    Gessi S. Varani K. Merighi S. Ongini E. Borea P. A. (2000). A2A adenosine receptors in human peripheral blood cells.Br. J. Pharmacol.129211. 10.1038/sj.bjp.0703045

  • 43

    Gonçalves F. Q. Lopes J. P. Silva H. B. Lemos C. Silva A. C. Gonçalves N. et al (2019). Synaptic and memory dysfunction in a beta-amyloid model of early Alzheimer’s disease depends on increased formation of ATP-derived extracellular adenosine.Neurobiol. Dis.132:104570. 10.1016/j.nbd.2019.104570

  • 44

    Gonçalves N. Simões A. T. Cunha R. A. de Almeida L. P. (2013). Caffeine and adenosine A2A receptor inactivation decrease striatal neuropathology in a lentiviral-based model of Machado-Joseph disease.Ann. Neurol.73655666. 10.1002/ana.23866

  • 45

    Hamilton S. P. Slager S. L. De Leon A. B. Heiman G. A. Klein D. F. Hodge S. E. et al (2004). Evidence for genetic linkage between a polymorphism in the adenosine A2A receptor and panic disorder.Neuropsychopharmacology29558565. 10.1038/sj.npp.1300311

  • 46

    He X. Chen F. Zhang Y. Gao Q. Guan Y. Wang J. et al (2020). Upregulation of adenosine A2A receptor and downregulation of GLT1 is associated with neuronal cell death in Rasmussen’s encephalitis.Brain Pathol.30246260. 10.1111/bpa.12770

  • 47

    Heyn J. Ledderose C. Hinske L. C. Limbeck E. Mohnle P. Lindner H. A. et al (2012). Adenosine A2A receptor upregulation in human PMNs is controlled by miRNA-214, miRNA-15, and miRNA-16.Shock37156163. 10.1097/SHK.0b013e31823f16bc

  • 48

    Hu Q. Ren X. Liu Y. Li Z. Zhang L. Chen X. et al (2016). Aberrant adenosine A2A receptor signaling contributes to neurodegeneration and cognitive impairments in a mouse model of synucleinopathy.Exp. Neurol.283213223. 10.1016/j.expneurol.2016.05.040

  • 49

    Huin V. Dhaenens C.-M. Homa M. Carvalho K. Buée L. Sablonnière B. (2019). Neurogenetics of the human adenosine receptor genes: genetic structures and involvement in brain diseases.J. Caffeine Adenosine Res.97388. 10.1089/caff.2019.0011

  • 50

    Ishibashi K. Miura Y. Wagatsuma K. Toyohara J. Ishiwata K. Ishii K. (2018). Occupancy of adenosine A2A receptors by istradefylline in patients with Parkinson’s disease using 11C-preladenant PET.Neuropharmacology143106112. 10.1016/j.neuropharm.2018.09.036

  • 51

    Janik P. Berdynski M. Safranow K. Zekanowski C. (2015). Association of ADORA1 rs2228079 and ADORA2A rs5751876 polymorphisms with Gilles de la Tourette syndrome in the Polish population.PLoS One10:e0136754. 10.1371/journal.pone.0136754

  • 52

    Kaster M. P. Machado N. J. Silva H. B. Nunes A. Ardais A. P. Santana M. et al (2015). Caffeine acts through neuronal adenosine A2A receptors to prevent mood and memory dysfunction triggered by chronic stress.Proc. Natl. Acad. Sci. USA11278337838. 10.1073/pnas.1423088112

  • 53

    Kobayashi S. Millhorn D. E. (1999). Stimulation of expression for the adenosine A2A receptor gene by hypoxia in PC12 cells. A potential role in cell protection.J. Biol. Chem.2742035820365. 10.1074/jbc.274.29.20358

  • 54

    Koos B. J. Kruger L. Murray T. F. (1997). Source of extracellular brain adenosine during hypoxia in fetal sheep.Brain Res.778439442. 10.1016/s0006-8993(97)01207-9

  • 55

    Kreth S. Ledderose C. Kaufmann I. Groeger G. Thiel M. (2008). Differential expression of 5′-UTR splice variants of the adenosine A2A receptor gene in human granulocytes: identification, characterization, and functional impact on activation.FASEB J.2232763286. 10.1096/fj.07-101097

  • 56

    Laurent C. Burnouf S. Ferry B. Batalha V. L. Coelho J. E. Baqi Y. et al (2016). A2A adenosine receptor deletion is protective in a mouse model of Tauopathy.Mol. Psychiatry2197107. 10.1038/mp.2015.115

  • 57

    Lee C. F. Lai H. L. Lee Y. C. Chien C. L. Chern Y. (2014). The A2A adenosine receptor is a dual coding gene: a novel mechanism of gene usage and signal transduction.J. Biol. Chem.28912571270. 10.1074/jbc.M113.509059

  • 58

    Lee Y. C. Chien C. L. Sun C. N. Huang C. L. Huang N. K. Chiang M. C. et al (2003a). Characterization of the rat A2A adenosine receptor gene: a 4.8-kb promoter-proximal DNA fragment confers selective expression in the central nervous system.Eur. J. Neurosci.1817861796. 10.1046/j.1460-9568.2003.02907.x

  • 59

    Lee Y. C. Lai H. L. Sun C. N. Chien C. L. Chern Y. (2003b). Identification of nuclear factor 1 (NF1) as a transcriptional modulator of rat A2A adenosine receptor.Brain Res. Mol. Brain Res.1116173. 10.1016/s0169-328x(02)00670-8

  • 60

    Li P. Rial D. Canas P. M. Yoo J. H. Li W. Zhou X. et al (2015). Optogenetic activation of intracellular adenosine A2A receptor signaling in the hippocampus is sufficient to trigger CREB phosphorylation and impair memory.Mol. Psychiatry2013391349. 10.1038/mp.2015.43

  • 61

    Li W. Dai S. An J. Xiong R. Li P. Chen X. et al (2009). Genetic inactivation of adenosine A2A receptors attenuates acute traumatic brain injury in the mouse cortical impact model.Exp. Neurol.2156976. 10.1016/j.expneurol.2008.09.012

  • 62

    Loy B. D. O’Connor P. J. Lindheimer J. B. Covert S. F. (2015). Caffeine is ergogenic for adenosine A2A receptor gene (ADORA2A) T allele homozygotes: a pilot study.J. Caffeine Res.57381. 10.1089/jcr.2014.0035

  • 63

    Machado N. J. Simões A. P. Silva H. B. Ardais A. P. Kaster M. P. Garção P. et al (2017). Caffeine reverts memory but not mood impairment in a depression-prone mouse strain with up-regulated adenosine A2A receptor in hippocampal glutamate synapses.Mol. Neurobiol.5415521563. 10.1007/s12035-016-9774-9

  • 64

    Madeira M. H. Elvas F. Boia R. Gonçalves F. Q. Cunha R. A. Ambrósio A. F. et al (2015). Adenosine A2AR blockade prevents neuroinflammation-induced death of retinal ganglion cells caused by elevated pressure.J. Neuroinflammation12:115. 10.1186/s12974-015-0333-5

  • 65

    Matos M. Augusto E. Machado N. J. dos Santos-Rodrigues A. Cunha R. A. Agostinho P. (2012). Astrocytic adenosine A2A receptors control the amyloid-beta peptide-induced decrease of glutamate uptake.J. Alzheimers. Dis.31555567. 10.3233/JAD-2012-120469

  • 66

    Melani A. Turchi D. Vannucchi M. G. Cipriani S. Gianfriddo M. Pedata F. (2005). ATP extracellular concentrations are increased in the rat striatum during in vivo ischemia.Neurochem. Int.47442448. 10.1016/j.neuint.2005.05.014

  • 67

    Meng F. Guo Z. Hu Y. Mai W. Zhang Z. Zhang B. et al (2019). CD73-derived adenosine controls inflammation and neurodegeneration by modulating dopamine signalling.Brain142700718. 10.1093/brain/awy351

  • 68

    Merighi S. Battistello E. Casetta I. Gragnaniello D. Poloni T. E. Medici V. et al (2021). Upregulation of cortical A2A adenosine receptors is reflected in platelets of patients with Alzheimer’s disease.J. Alzheimers. Dis.8011051117. 10.3233/jad-201437

  • 69

    Miao J. Liu L. Yan C. Zhu X. Fan M. Yu P. et al (2019). Association between ADORA2A gene polymorphisms and schizophrenia in the North Chinese Han population.Neuropsychiatr. Dis. Treat.1524512458. 10.2147/NDT.S205014

  • 70

    Micioni Di Bonaventura M. V. Pucci M. Giusepponi M. E. Romano A. Lambertucci C. Volpini R. et al (2019). Regulation of adenosine A2A receptor gene expression in a model of binge eating in the amygdaloid complex of female rats.J. Psychopharmacol.3315501561. 10.1177/0269881119845798

  • 71

    Mishina M. Ishiwata K. Naganawa M. Kimura Y. Kitamura S. Suzuki M. et al (2011). Adenosine A2A receptors measured with [11C]TMSX PET in the striata of Parkinson’s disease patients.PLoS One6:e17338. 10.1371/journal.pone.0017338

  • 72

    Moreira-de-Sá A. Gonçalves F. Q. Lopes J. P. Silva H. B. Tomé A. R. Cunha R. A. et al (2020). Adenosine A2A receptors format long-term depression and memory strategies in a mouse model of Angelman syndrome.Neurobiol. Dis.146:105137. 10.1016/j.nbd.2020.105137

  • 73

    Moreira-de-Sá A. Gonçalves F. Q. Lopes J. P. Silva H. B. Tomé A. R. Cunha R. A. et al (2021). Motor deficits coupled to cerebellar and striatal alterations in Ube3am–/p+ mice modelling Angelman syndrome are attenuated by adenosine A2A receptor blockade.Mol. Neurobiol.5825432557. 10.1007/s12035-020-02275-9

  • 74

    Morello S. Ito K. Yamamura S. Lee K. Y. Jazrawi E. Desouza P. et al (2006). IL-1 beta and TNF-alpha regulation of the adenosine receptor A2A expression: differential requirement for NF-kappa B binding to the proximal promoter.J. Immunol.17771737183. 10.4049/jimmunol.177.10.7173

  • 75

    Ng S. K. Higashimori H. Tolman M. Yang Y. (2015). Suppression of adenosine 2A receptor (A2AR)-mediated adenosine signaling improves disease phenotypes in a mouse model of amyotrophic lateral sclerosis.Exp. Neurol.267115122. 10.1016/j.expneurol.2015.03.004

  • 76

    Nunes R. A. Mazzotti D. R. Hirotsu C. Andersen M. L. Tufik S. Bittencourt L. (2017). The association between caffeine consumption and objective sleep variables is dependent on ADORA2A c.1083T>C genotypes.Sleep Med.30210215. 10.1016/j.sleep.2016.06.038

  • 77

    Oliveira S. Ardais A. P. Bastos C. R. Gazal M. Jansen K. de Mattos Souza L. et al (2019). Impact of genetic variations in ADORA2A gene on depression and symptoms: a cross-sectional population-based study.Purinergic Signal.153744. 10.1007/s11302-018-9635-2

  • 78

    Orr A. G. Hsiao E. C. Wang M. M. Ho K. Kim D. H. Wang X. et al (2015). Astrocytic adenosine receptor A2A and Gs-coupled signaling regulate memory.Nat. Neurosci.18423434. 10.1038/nn.3930

  • 79

    Orr A. G. Lo I. Schumacher H. Ho K. Gill M. Guo W. et al (2018). Istradefylline reduces memory deficits in aging mice with amyloid pathology.Neurobiol. Dis.1102936. 10.1016/j.nbd.2017.10.014

  • 80

    Orrú M. Quiroz C. Guitart X. Ferré S. (2011). Pharmacological evidence for different populations of postsynaptic adenosine A2A receptors in the rat striatum.Neuropharmacology61967974. 10.1016/j.neuropharm.2011.06.025

  • 81

    Padilla K. M. Quintanar-Setephano A. López-Vallejo F. Berumen L. C. Miledi R. Garcia-Alcocer G. (2018). Behavioral changes induced through adenosine A2A receptor ligands in a rat depression model induced by olfactory bulbectomy.Brain Behav.8:e00952. 10.1002/brb3.952

  • 82

    Pagnussat N. Almeida A. S. Marques D. M. Nunes F. Chenet G. C. Botton P. H. et al (2015). Adenosine A2A receptors are necessary and sufficient to trigger memory impairment in adult mice.Br. J. Pharmacol.17238313845. 10.1111/bph.13180

  • 83

    Patodia S. Paradiso B. Garcia M. Ellis M. Diehl B. Thom M. et al (2020). Adenosine kinase and adenosine receptors A1R and A2AR in temporal lobe epilepsy and hippocampal sclerosis and association with risk factors for SUDEP.Epilepsia61787797. 10.1111/epi.16487

  • 84

    Peterfreund R. A. MacCollin M. Gusella J. Fink J. S. (1996). Characterization and expression of the human A2A adenosine receptor gene.J. Neurochem.66362368. 10.1046/j.1471-4159.1996.66010362.x

  • 85

    Popat R. A. Van Den Eeden S. K. Tanner C. M. Kamel F. Umbach D. M. Marder K. et al (2011). Coffee, ADORA2A, and CYP1A2: the caffeine connection in Parkinson’s disease.Eur. J. Neurol.18756765. 10.1111/j.1468-1331.2011.03353.x

  • 86

    Rebola N. Coelho J. E. Costenla A. R. Lopes L. V. Parada A. Oliveira C. R. et al (2003). Decrease of adenosine A1 receptor density and of adenosine neuromodulation in the hippocampus of kindled rats.Eur. J. Neurosci.18820828. 10.1046/j.1460-9568.2003.02815.x

  • 87

    Rebola N. Porciúncula L. O. Lopes L. V. Oliveira C. R. Soares-da-Silva P. Cunha R. A. (2005). Long-term effect of convulsive behavior on the density of adenosine A1 and A2A receptors in the rat cerebral cortex.Epilepsia46(Suppl. 5), 159165. 10.1111/j.1528-1167.2005.01026.x

  • 88

    Rei N. Rombo D. M. Ferreira M. F. Baqi Y. Müller C. E. Ribeiro J. A. et al (2020). Hippocampal synaptic dysfunction in the SOD1(G93A) mouse model of Amyotrophic Lateral Sclerosis: Reversal by adenosine A2AR blockade.Neuropharmacology171:108106. 10.1016/j.neuropharm.2020.108106

  • 89

    Rétey J. V. Adam M. Khatami R. Luhmann U. F. Jung H. H. Berger W. et al (2007). A genetic variation in the adenosine A2A receptor gene (ADORA2A) contributes to individual sensitivity to caffeine effects on sleep.Clin. Pharmacol. Ther.81692698. 10.1038/sj.clpt.6100102

  • 90

    Ribeiro D. E. Roncalho A. L. Glaser T. Ulrich H. Wegener G. Joca S. (2019). P2X7 receptor signaling in stress and depression.Int. J. Mol. Sci.20:2778. 10.3390/ijms20112778

  • 91

    Rodrigues R. J. Tomé A. R. Cunha R. A. (2015). ATP as a multi-target danger signal in the brain.Front. Neurosci.9:148. 10.3389/fnins.2015.00148

  • 92

    Rogers P. J. Hohoff C. Heatherley S. V. Mullings E. L. Maxfield P. J. Evershed R. P. et al (2010). Association of the anxiogenic and alerting effects of caffeine with ADORA2A and ADORA1 polymorphisms and habitual level of caffeine consumption.Neuropsychopharmacology3519731983. 10.1038/npp.2010.71

  • 93

    Schoen S. W. Kreutzberg G. W. (1997). 5′-nucleotidase enzyme cytochemistry as a tool for revealing activated glial cells and malleable synapses in CNS development and regeneration.Brain Res. Brain Res. Protoc.13343. 10.1016/s1385-299x(96)00006-2

  • 94

    Schoen S. W. Ebert U. Löscher W. (1999). 5′-Nucleotidase activity of mossy fibers in the dentate gyrus of normal and epileptic rats.Neuroscience93519526. 10.1016/s0306-4522(99)00135-9

  • 95

    Schwarzschild M. A. Agnati L. Fuxe K. Chen J. F. Morelli M. (2006). Targeting adenosine A2A receptors in Parkinson’s disease.Trends Neurosci.29647654. 10.1016/j.tins.2006.09.004

  • 96

    Seven Y. B. Simon A. K. Sajjadi E. Zwick A. Satriotomo I. Mitchell G. S. (2020). Adenosine A2A receptor inhibition protects phrenic motor neurons from cell death induced by protein synthesis inhibition.Exp. Neurol.323:113067. 10.1016/j.expneurol.2019.113067

  • 97

    Shen H. Y. Canas P. M. Garcia-Sanz P. Lan J. Q. Boison D. Moratalla R. et al (2013). Adenosine A2A receptors in striatal glutamatergic terminals and GABAergic neurons oppositely modulate psychostimulant action and DARPP-32 phosphorylation.PLoS One8:e80902. 10.1371/journal.pone.0080902

  • 98

    Shen H. Y. Coelho J. E. Ohtsuka N. Canas P. M. Day Y. J. Huang Q. Y. et al (2008). A critical role of the adenosine A2A receptor in extrastriatal neurons in modulating psychomotor activity as revealed by opposite phenotypes of striatum and forebrain A2A receptor knock-outs.J. Neurosci.2829702975. 10.1523/JNEUROSCI.5255-07.2008

  • 99

    Shinohara M. Saitoh M. Nishizawa D. Ikeda K. Hirose S. Takanashi J. et al (2013). ADORA2A polymorphism predisposes children to encephalopathy with febrile status epilepticus.Neurology8015711576. 10.1212/WNL.0b013e31828f18d8

  • 100

    Silva A. C. Lemos C. Gonçalves F. Q. Pliássova A. V. Machado N. J. Silva H. B. et al (2018). Blockade of adenosine A2A receptors recovers early deficits of memory and plasticity in the triple transgenic mouse model of Alzheimer’s disease.Neurobiol. Dis.1177281. 10.1016/j.nbd.2018.05.024

  • 101

    Simões A. P. Machado N. J. Gonçalves N. Kaster M. P. Simões A. T. Nunes A. et al (2016). Adenosine A2A receptors in the amygdala control synaptic plasticity and contextual fear memory.Neuropsychopharmacology4128622871. 10.1038/npp.2016.98

  • 102

    Smith M. D. Bhatt D. P. Geiger J. D. Rosenberger T. A. (2014). Acetate supplementation modulates brain adenosine metabolizing enzymes and adenosine A2A receptor levels in rats subjected to neuroinflammation.J. Neuroinflammation11:99. 10.1186/1742-2094-11-99

  • 103

    Sun M. J. Liu F. Zhao Y. F. Wu X. A. (2020). In vivo positron emission tomography imaging of adenosine A2A receptors.Front. Pharmacol.11:599857. 10.3389/fphar.2020.599857

  • 104

    Svenningsson P. Le Moine C. Fisone G. Fredholm B. B. (1999). Distribution, biochemistry and function of striatal adenosine A2A receptors.Prog. Neurobiol.59355396. 10.1016/s0301-0082(99)00011-8

  • 105

    Taherzadeh-Fard E. Saft C. Wieczorek S. Epplen J. T. Arning L. (2010). Age at onset in Huntington’s disease: replication study on the associations of ADORA2A, HAP1 and OGG1.Neurogenetics11435439. 10.1007/s10048-010-0248-3

  • 106

    Temido-Ferreira M. Ferreira D. G. Batalha V. L. Marques-Morgado I. Coelho J. E. Pereira P. et al (2020). Age-related shift in LTD is dependent on neuronal adenosine A2A receptors interplay with mGluR5 and NMDA receptors.Mol. Psychiatry2518761900. 10.1038/s41380-018-0110-9

  • 107

    Tescarollo F. C. Rombo D. M. DeLiberto L. K. Fedele D. E. Alharfoush E. Tomé A. R. et al (2020). Role of adenosine in epilepsy and seizures.J. Caffeine Adenosine Res.104560. 10.1089/caff.2019.0022

  • 108

    Tian T. Zhou Y. Feng X. Ye S. Wang H. Wu W. et al (2016). MicroRNA-16 is putatively involved in the NF-kappaB pathway regulation in ulcerative colitis through adenosine A2A receptor (A2AR) mRNA targeting.Sci. Rep.6:30824. 10.1038/srep30824

  • 109

    Viana da Silva S. Haberl M. G. Zhang P. Bethge P. Lemos C. Gonçalves N. et al (2016). Early synaptic deficits in the APP/PS1 mouse model of Alzheimer’s disease involve neuronal adenosine A2A receptors.Nat. Commun.7:11915. 10.1038/ncomms11915

  • 110

    Villar-Menéndez I. Porta S. Buira S. P. Pereira-Veiga T. Díaz-Sánchez S. Albasanz J. L. et al (2014). Increased striatal adenosine A2A receptor levels is an early event in Parkinson’s disease-related pathology and it is potentially regulated by miR-34b.Neurobiol. Dis.69206214.

  • 111

    Vincenzi F. Corciulo C. Targa M. Casetta I. Gentile M. Granieri E. et al (2013). A2A adenosine receptors are up-regulated in lymphocytes from amyotrophic lateral sclerosis patients.Amyotroph. Lateral Scler. Frontotemporal Degener.14406413. 10.3109/21678421.2013.793358

  • 112

    Wei C. J. Augusto E. Gomes C. A. Singer P. Wang Y. Boison D. et al (2014). Regulation of fear responses by striatal and extrastriatal adenosine A2A receptors in forebrain.Biol. Psychiatry75855863. 10.1016/j.biopsych.2013.05.003

  • 113

    Wieraszko A. Seyfried T. N. (1989). Increased amount of extracellular ATP in stimulated hippocampal slices of seizure prone mice.Neurosci. Lett.106287293. 10.1016/0304-3940(89)90178-x

  • 114

    Yu L. Frith M. C. Suzuki Y. Peterfreund R. A. Gearan T. Sugano S. et al (2004). Characterization of genomic organization of the adenosine A2A receptor gene by molecular and bioinformatics analyses.Brain Res.1000156173. 10.1016/j.brainres.2003.11.072

  • 115

    Yu L. Shen H. Y. Coelho J. E. Araújo I. M. Huang Q. Y. Day Y. J. et al (2008). Adenosine A2A receptor antagonists exert motor and neuroprotective effects by distinct cellular mechanisms.Ann. Neurol.63338346. 10.1002/ana.21313

  • 116

    Zhao L. Liu Y. W. Yang T. Gan L. Yang N. Dai S. S. et al (2015). The mutual regulation between miR-214 and A2AR signaling plays an important role in inflammatory response.Cell Signal.2720262034. 10.1016/j.cellsig.2015.07.007

  • 117

    Zhao Z. A. Li P. Ye S. Y. Ning Y. L. Wang H. Peng Y. et al (2017). Perivascular AQP4 dysregulation in the hippocampal CA1 area after traumatic brain injury is alleviated by adenosine A2A receptor inactivation.Sci. Rep.7:2254. 10.1038/s41598-017-02505-6

  • 118

    Zheng F. Zhou Y. T. Feng D. D. Li P. F. Tang T. Luo J. K. et al (2020). Metabolomics analysis of the hippocampus in a rat model of traumatic brain injury during the acute phase.Brain Behav.10:e01520. 10.1002/brb3.1520

Summary

Keywords

adenosine A2A receptors, central nervous system, antagonism, caffeine, biomarkers, polymorphisms

Citation

Moreira-de-Sá A, Lourenço VS, Canas PM and Cunha RA (2021) Adenosine A2A Receptors as Biomarkers of Brain Diseases. Front. Neurosci. 15:702581. doi: 10.3389/fnins.2021.702581

Received

29 April 2021

Accepted

22 June 2021

Published

16 July 2021

Volume

15 - 2021

Edited by

Rui Daniel Prediger, Federal University of Santa Catarina, Brazil

Reviewed by

Thomas Heinbockel, Howard University, United States; Ernest Jennings, James Cook University, Australia

Updates

Copyright

*Correspondence: Rodrigo A. Cunha, ;

These authors have contributed equally to this work and share first authorship

This article was submitted to Neuropharmacology, a section of the journal Frontiers in Neuroscience

Disclaimer

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.

Outline

Cite article

Copy to clipboard


Export citation file


Share article

Article metrics