Positive allosteric adenosine A(2A) receptor modulation suppresses insomnia associated with mania- and schizophrenia-like behaviors in mice

Background: Insomnia is associated with psychiatric illnesses such as bipolar disorder or schizophrenia. Treating insomnia improves psychotic symptoms severity, quality of life, and functional outcomes. Patients with psychiatric disorders are often dissatisfied with the available therapeutic options for their insomnia. In contrast, positive allosteric modulation of adenosine A(2A) receptors (A(2A)Rs) leads to slow-wave sleep without cardiovascular side effects in contrast to A(2A)R agonists. Methods: We investigated the hypnotic effects of A(2A)R positive allosteric modulators (PAMs) in mice with mania-like behavior produced by ablating GABAergic neurons in the ventral medial midbrain/pons area and in a mouse model of schizophrenia by knocking out of microtubule-associated protein 6. We also compared the properties of sleep induced by A(2A)R PAMs in mice with mania-like behavior with those induced by DORA-22, a dual orexin receptor antagonist that improves sleep in pre-clinical models, and the benzodiazepine diazepam. Results: A(2A)R PAMs suppress insomnia associated with mania- or schizophrenia-like behaviors in mice. A(2A)R PAM-mediated suppression of insomnia in mice with mania-like behavior was similar to that mediated by DORA-22, and, unlike diazepam, did not result in abnormal sleep. Conclusion: A(2A)R allosteric modulation may represent a new therapeutic avenue for sleep disruption associated with bipolar disorder or psychosis.