Dual Mechanisms of the Diazepine-Benzimidazole Derivative, DAB-19, in Modulating Glutamatergic Neurotransmission

The search for novel compounds with anticonvulsant properties remains a key focus in neuropharmacology. Recently, the diazepine-benzimidazole derivative, DAB-19, has emerged as a promising candidate due to its demonstrated anxiolytic and analgesic effects. In this study, we investigate the mechanisms underlying DAB-19's activity, focusing on its impact on glutamatergic transmission, a key target in the pathophysiology of various central nervous system disorders. Intriguingly, while DAB-19 suppressed evoked glutamatergic transmission in rat brain slices, it simultaneously enhanced spontaneous neurotransmission. Further experiments on glutamatergic neuromuscular synapses in fly larvae revealed two distinct mechanisms: calcium-dependent potentiation of glutamate release and inhibition of spike propagation via blockade of voltage-gated sodium channels. The latter effect was directly confirmed in rat brain neurons. Given its action on sodium channels, we tested DAB-19 in the pentylenetetrazole model, where it delayed seizure onset but did not prevent seizures. These findings position DAB-19 as a multifaceted compound with significant therapeutic potential.