The Emerging Role of Inflammasomes as Central Mediators in Inflammatory Bladder Pathology

Irritative voiding symptoms (e.g. increased frequency and urgency) occur in many common pathologic conditions such as urinary tract infections and bladder outlet obstruction, and these conditions are well-established to have underlying inflammation that directly triggers these symptoms. However, it remains unclear as to how such diverse stimuli individually generate a common inflammatory process. Jürg Tschopp provided substantial insight into this conundrum when, working with extracts from THP-1 cells, he reported the existence of the inflammasome. He described it as a structure that senses multiple diverse signals from intracellular/extracellular sources and pathogens and triggers inflammation by the maturation and release of the pro-inflammatory cytokines interleukin-1β and interleukin-18. Recently, many of these sensors were found in the bladder and the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3, has been shown to be a central mediator of inflammation in several urological diseases. In this review, we introduce the nucleotide-binding domain, leucine-rich-containing family, pyrin domaincontaining-3 inflammasome, highlight its emerging role in several common urologic conditions, and speculate on the potential involvement of other inflammasomes in bladder pathology.