Lead optimization of AMS-17 identifies AMS-4 as a modulator of inflammasome-driven cocaine-associated neuroinflammation

Cocaine use disorder (CUD) affects approximately 22.5 million people worldwide and is a major public health concern due to its widespread abuse and severe neuropsychiatric effects. Cocaine exposure induces neuroinflammation primarily through NLRP3 inflammasome activation in microglial cells, which releases proinflammatory cytokines such as IL-1β that contribute to neuronal dysfunction, making NLRP3 a key mediator of cocaine-induced neuropathology. Due to its critical role in neuroinflammatory signaling, the NLRP3 inflammasome is a promising therapeutic target for CUD. However, the development of effective and selective NLRP3 inhibitors remain limited due to challenges with specificity, bioavailability, and off-target effects. Thus, this study aimed to develop novel tertiary sulfonylurea compounds with selective inhibitory activity against the NLRP3 inflammasome and to investigate their efficacy in the context of cocaine exposure. We designed and synthesized five tertiary sulfonylurea-derived compounds. These compounds were structurally-inspired from AMS-17 by changing the two aromatic rings in AMS-17, while maintaining the cyclic urea. We tested their effects on NLRP3 activation in microglia. Thus, the BV2 cells were pre-treated with the novel compounds for 1 h, followed by cocaine exposure. Expression of NFκB, NLRP3 and its downstream signaling executer proteins were analyzed by Western blotting. Our results demonstrate that AMS-17 and its four derivatives exhibited varying levels of inhibition, with AMS-4 demonstrating the most pronounced effect, significantly reducing both NLRP3 and IL-1β expression. These findings suggest that selective sulfonylurea-based NLRP3 inhibitors, particularly AMS-4, may represent a promising therapeutic strategy for mitigating neuroinflammation associated with CUD.