Background: The NOD-like receptor protein (NLRP)3 inflammasome is at the signaling hub center to instigate inflammation in response to pathogen infection or oxidative stress, and its tight control is pivotal for immune defense against infection while avoiding parallel intensive inflammatory tissue injury. Acetylation of NLRP3 is critical for the full activation of NLRP3 inflammasome, while the precise regulation of the acetylation and deacetylation circuit of NLRP3 protein remained to be fully understood.
Methods: The interaction between histone deacetylase 10 (HDAC10) and NLRP3 was detected by immunoprecipitation and western blot in the HDAC10 and NLRP3 overexpressing cells. The role of HDAC10 in NLRP3 inflammasome activation was measured by immunofluorescence, real-time PCR and immunoblotting assay in peritoneal macrophages and bone marrow-derived macrophages after the stimulation with LPS and ATP. To investigate the role of HDAC10 in NLRP3-involved inflammatory diseases, the Hdac10 knockout (Hdac10-/-) mice were used to construct the LPS-induced acute endotoxemia model and folic acid-induced acute tubular necrosis model. Tissue injury level was analyzed by hematoxylin and eosin staining, and the serum level of IL-1β was measured by enzyme-linked immunosorbent assay (ELISA). The conservative analysis and immunoprecipitation assay were performed to screen the precise catalytic site regulated by HDAC10 responsible for the switching from the acetylation to ubiquitination of NLRP3.
Results: Here we demonstrated that HDAC10 directly interacted with NLRP3 and induced the deacetylation of NLRP3, thus leading to the inhibition of NLRP3 inflammasome and alleviation of NLRP3 inflammasome-mediated acute inflammatory injury. Further investigation demonstrated that HDAC10 directly induced the deacetylation of NLRP3 at K496 residue, thus switching NLRP3 acetylation to the ubiquitination modification, resulting in the proteasomal degradation of NLRP3 protein. Thus, this study identified HDAC10 as a new eraser for NLRP3 acetylation, and HDAC10 attenuated NLRP3 inflammasome involved acute inflammation via directly deacetylating NLRP3.
Conclusions: This study indicated that HDAC10 switched NLRP3 modification from acetylation to ubiquitination and attenuated acute inflammatory diseases, thus it provided a potential therapeutic strategy for NLRP3 inflammasome-associated diseases by targeting HDAC10.
Keywords: Acute inflammation; Deacetylation; HDAC10; NLRP3 inflammasome; Ubiquitination.
The NOD-like receptor protein (NLRP)3 inflammasome is the core signaling hub and key instigator of acute inflammation in response to infection and oxidative stress to promote inflammatory cascade responses. Although inflammasome activation protects against infection and injury, excessive NLRP3 inflammasome activity yields excessive cytokine secretion and a pathological hyperinflammatory state. Of increasing interest is the critical contribution of NLRP3 inflammasome to acute inflammatory injury. Thus, the activation of NLRP3 inflammasome must be tightly controlled to ensure its efficient biological function without excessive side effect. NLRP3 protein is rich in lysine and susceptible to both acetylation and ubiquitination modification, while these two modifications usually had opposing effects on the protein degradation and stability. Various post-translational modifications in inflammasome signaling can be cross-regulated by each other, whereas the machinery involved in their spatial coordination during the process of NLRP3 inflammasome activation remains to be fully understood. Here we demonstrated that HDAC10 negatively regulated NLRP3 inflammasome by switching from acetylation to ubiquitination modification, leading to the proteasome-mediated degradation of the NLRP3 protein and attenuation of NLRP3 inflammasome activation. The further ubiquitination and acetylation analysis revealed that the Lys496 residue of NLRP3 protein is the pivotal convergence point involved in this PTM switch, indicating the critical switching node effect of this lysine residue. Altogether, our work suggested a novel fine-tuned regulatory mechanism of NLRP3 inflammasome activation by HDAC10, and provided a potential therapeutic target for NLRP3 inflammasome-associated diseases.
© 2024. The Author(s).