NLRP3 inflammasome in traumatic brain injury: Its implication in the disease pathophysiology and potential as a therapeutic target

Traumatic brain injury (TBI), an acquired brain injury imparted by a mechanical trauma to the head, has significant ramifications in terms of long-term disability and cost of healthcare. TBI is characterized by an initial phase of cell death owing to direct mechanical injury, followed by a secondary phase in which neuroinflammation plays a pivotal role. Activation of inflammasome complexes triggers a cascade that leads to activation of inflammatory mediators such as caspase-1, Interleukin (IL)-18, and IL-1β, eventually causing pyroptosis. NLRP3 inflammasome, a component of the innate immune response, has been implicated in a number of neurodegenerative diseases, including TBI. Recent findings indicate that NLRP3 inhibitors can potentially ameliorate neuroinflammation and improve cognition and motor function in TBI. The NLRP3 inflammasome also holds potential as a predictive biomarker for the long-term sequelae following TBI. Although several therapeutic agents have shown promising results in pre-clinical studies, none of them have been effective in human trials for TBI, to date. Thus, it is imperative that such promising therapeutic candidates are evaluated in clinical trials to assess their efficacy in alleviating neurological impairments in TBI. This review offers an insight into the pathophysiology of TBI, with an emphasis on neuroinflammation in the aftermath of TBI. We highlight the NLRP3 inflammasome and explore its role in the neuroinflammatory cascade in TBI. We also shed light on its potential as a prospective biomarker and therapeutic target for TBI management.