Design, Synthesis, And Evaluation of Functionalized Diamino-butylbenzamides As Selective Dopamine D3 Receptor Ligands

Substance use disorder remains a major, unmet medical need. Cocaine is one of the most commonly abused recreational drugs and in 2018, there were over 5.5 million current cocaine users. There are no approved therapies for the treatment of cocaine use disorder, but the D3 dopamine receptor has been identified as a potential therapeutic target. We have identified a series of functionalized diamino-butylbenzamides that are potent D3 binders with moderate to high selectivity for D3 over D2.

Self-grooming promotes social interaction in mice via chemosensory communication

Self-grooming is a stereotyped behavior displayed by nearly all animals. Among other established functions, self-grooming is implicated in social communication in some animals. However, whether self-grooming specifically influences behaviors of nearby individuals has not been directly tested, partly due to the technical challenge of inducing self-grooming in a reliable and temporally controllable manner. We recently found that optogenetic activation of dopamine D3 receptor expressing neurons in the ventral striatal islands of Calleja robustly induces orofacial grooming in mice. Using this optogenetic manipulation, here we demonstrate that observer mice display social preference for grooming over non-grooming mice regardless of biological sex. Moreover, grooming-induced social attraction depends on volatile chemosensory cues broadcasted from grooming mice. Collectively, our study establishes self-grooming as a means of promoting social interaction among mice via volatile cues, suggesting an additional benefit for animals to allocate a significant amount of time to this behavior.

Dopamine D3 Receptor Ligand Suppresses the Expression of Levodopa-Induced Dyskinesia in Nonhuman Primate Model of Parkinson's Disease

Parkinson's disease (PD) is a complex multisystem, chronic and so far incurable disease with significant unmet medical needs. The incidence of PD increases with aging and the expected burden will continue to escalate with our aging population. Since its discovery in the 1961 levodopa remains the gold standard pharmacotherapy for PD. However, the progressive nature of the neurodegenerative process in and beyond the nigrostriatal system causes a multitude of side effects, including levodopa-induced dyskinesia within 5 years of therapy. Attenuating dyskinesia has been a significant challenge in the clinical management of PD. We report on a small molecule that eliminates the expression of levodopa-induced dyskinesia and significantly improves PD-like symptoms. The lead compound PD13R we discovered is a dopamine D3 receptor partial agonist with high affinity and selectivity, orally active and with desirable drug-like properties. Future studies are aimed at developing this lead compound for treating PD patients with dyskinesia.

Dopamine D3 Receptor Ligand Suppresses the Expression of Levodopa-Induced Dyskinesia in Nonhuman Primate Model of Parkinson's Disease

Parkinson’s disease (PD) is a complex multisystem, chronic and so far incurable disease with significant unmet medical needs. The incidence of PD increases with aging and the expected burden will continue to escalate with our aging population. Since its discovery in the 1961 levodopa remains the gold standard pharmacotherapy for PD. However, the progressive nature of the neurodegenerative process in and beyond the nigrostriatal system causes a multitude of side effects, including levodopa-induced dyskinesia within 5 years of therapy. Attenuating dyskinesia has been a significant challenge in the clinical management of PD. We report on a small molecule that eliminates the expression of levodopa-induced dyskinesia and significantly improves PD-like symptoms. The lead compound PD13R we discovered is a dopamine D3 receptor partial agonist with high affinity and selectivity, orally active and with desirable drug-like properties. Future studies are aimed at developing this lead compound for treating PD patients with dyskinesia.