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Abstract Purpose Cognitive impairment is a critical complication of acute respiratory distress syndrome (ARDS). However, effective interventions are lacking. Growing evidence demonstrates that c‐Jun N‐terminal kinase (JNK)‐mediated neuroinflammation is involved in the development of ARDS. Therefore, we hypothesized that the JNK pathway is involved in ARDS‐induced cognitive impairment. Methods An in vivo rat model of ARDS was established by treating it with lipopolysaccharide. The cognitive function was assessed by behavioral tests. The levels of pro‐inflammatory cytokines, JNK and NOD‐, LRR‐, and pyrin domain‐containing protein 3 (NLRP3) were analyzed by enzyme‐linked immunosorbent assay, western blot, or immunohistochemical analysis. Results We found that JNK inhibitor 8 (JNK‐IN‐8) alleviated cognitive impairment, neuroinflammation, and NLRP3 inflammasome activation in the ARDS rat model. Additionally, an in vivo study showed that the protective effect of JNK‐IN‐8 on cognitive impairment was blocked by nigericin, an NLRP3 activator. Conclusions Our data suggest that JNK‐IN‐8 treatment improves ARDS‐induced cognitive impairment by inhibiting the JNK/nuclear factor‐κB‐mediated NLRP3 inflammasome.

Acute kidney injury (AKI) is a frequent and serious complication of sepsis, which results in a rapid decline of kidney function. Currently, there are no curative therapies for AKI. Theacrine is a purine alkaloid and exerts significant role in regulating inflammation, oxidative stress, and mood elevation. The study aims to evaluate the biological role and potential mechanism of theacrine in septic AKI. The murine and cellular models of septic AKI were established in lipopolysaccharide (LPS)-treated C57BL/6 mice and HK-2 cells, respectively. The effect of theacrine on alleviating septic AKI was assessed after pretreatment with theacrine in vivo and in vitro. We found that theacrine treatment significantly alleviated LPS-induced kidney injury, as evidenced by decreased levels of kidney injury markers (blood urea nitrogen and creatinine), inflammatory factors (IL-1β and IL-18), and cell apoptosis in vivo and in vitro. Mechanistically, theacrine markedly repressed the activation of NOD-like receptor (NLR) pyrin domain-containing protein 3 (NLRP3)inflammasome. As expected, MCC950 (a specific inhibitor of NLRP3) treatment also decreased LPS-induced production of IL-18 and IL-1β and cell apoptosis in HK-2 cells. More important, Nigericin sodiumsalt (a NLRP3 agonist) damaged the effect of theacrine on repressing kidney injury markers (blood urea nitrogen and creatinine), pro-inflammatory cytokines (IL-18 and IL-1β), and cell apoptosis. Taken together, these results demonstrate that theacrine alleviates septic AKI, at least in part by repressing the activation of NLRP3 inflammasome.