AUTHOR=Tian Di , Xing Yanmei , Gao Wenli , Zhang Hongyan , Song Yifeng , Tian Ya , Dai Zhongliang 

TITLE=Sevoflurane Aggravates the Progress of Alzheimer’s Disease Through NLRP3/Caspase-1/Gasdermin D Pathway

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=9

YEAR=2022

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2021.801422

DOI=10.3389/fcell.2021.801422

ISSN=2296-634X

ABSTRACT=<p><bold>Background:</bold> Alzheimer’s disease (AD) is the most common form of dementia worldwide. Previous studies have reported that sevoflurane, a frequently used anesthetic, can induce cognitive impairment in preclinical and clinical settings. However, the mechanism underlying the development of this neurotoxicity is currently unclear.</p><p><bold>Methods:</bold> Seven-month-old APP/PS1 mice were placed in an anesthesia induction box containing 3% sevoflurane in 100% O<sub>2</sub> for 6 h, while BV2 cells were cultured with 4% sevoflurane for 6 h. Pyroptosis and tau protein expression in excised hippocampus tissues and cells were measured using Western blotting and immunofluorescence assay. Caspase-1 and NLRP3 were knocked out in BV2 microglia using CRISPR/Cas9 technology to determine whether they mediate the effects induced by sevoflurane.</p><p><bold>Results:</bold> Sevoflurane directly activated caspase-1 to induce pyroptosis in the mouse model of AD via NLRP3 and AIM2 activation. In addition, sevoflurane mediated cleavage of gasdermin D (GSDMD) but not gasdermin E (GSDME), promoted the biosynthesis of downstream interleukin-1<italic>β</italic> and interleukin-18, and increased <italic>β</italic>-amyloid (A<italic>β</italic>) deposition and tau phosphorylation. The nontoxic caspase-1 small-molecule inhibitor VX-765 significantly inhibited this activation process in microglia, while NLRP3 deletion suppressed sevoflurane-induced caspase-1 cleavage and subsequently pyroptosis, as well as tau pathology. Furthermore, silencing caspase-1 alleviated the sevoflurane-induced release of IL-1β and IL-18 and inhibited tau-related enzymes in microglia.</p><p><bold>Conclusion:</bold> This study is the first to report that clinical doses of sevoflurane aggravate the progression of AD via the NLRP3/caspase-1/GSDMD axis. Collectively, our findings elucidate the crucial mechanisms of NLRP3/caspase-1 in pyroptosis and tau pathogenesis induced by sevoflurane and suggest that VX-765 could represent a novel therapeutic intervention for treating AD.</p>