CEBPD is a pivotal factor for the activation of NLRP3 inflammasome in traumatic brain injury.

Traumatic brain injury (TBI) is a significant global health concern and a leading cause of mortality and disability worldwide. Neuroinflammation is a pivotal pathological mechanism underlying secondary brain injury following TBI. CCAAT enhancer-binding protein-delta (CEBPD), a transcription factor necessary for regulating immune and inflammatory responses, plays an important role in the progression of neuroinflammatory disorders. However, the role of CEBPD in the prognosis of TBI needs to be determined. We found that the expression of CEBPD increased significantly in TBI patients and animal models, as well as in the HT-22 neuron mechanical scratch injury model. The inhibition of CEBPD by in vivo siRNA effectively suppressed neuronal death, brain edema, and brain contusion volume and alleviated neurofunctional deficits. Knocking down CEBPD considerably inhibited the activation of the neuronal NLRP3 inflammasome, downregulated the expression of the GSDMD N-terminal fragment, and reduced the production of IL-1β and IL-18, significantly mitigating neuronal pyroptosis after TBI. Increasing CEBPD levels led to the activation of the NLRP3 inflammasome and neuronal pyroptosis in the mechanical scratch injury cell model. We also determined that the NLRP3 inflammasome activated by nigericin depended on the CEBPD pathway following TBI. Our results suggested that CEBPD may serve as a pivotal factor in promoting neuronal pyroptosis and that inhibiting CEBPD might be a promising strategy for treating TBI.