GSDMD Mediates LPS-Induced Septic Myocardial Dysfunction by Regulating ROS-dependent NLRP3 Inflammasome Activation

Abstract

Myocardial dysfunction is a serious consequence of sepsis and contributes to high mortality. Currently, the molecular mechanism of myocardial dysfunction induced by sepsis remains unclear. In the present study, we investigated the role of gasdermin D (GSDMD) in cardiac dysfunction in septic mice and the underlying mechanism. C57BL/6 wild-type (WT) mice and age-matched Gsdmd-knockout (Gsdmd-/-) mice were intraperitoneally injected with lipopolysaccharide (LPS) (10 mg/kg) to mimic sepsis. The results showed that GSDMD-NT, the functional fragment of GSDMD, was upregulated in the heart tissue of septic WT mice induced by LPS, which was accompanied by decreased cardiac function and myocardial injury, as shown by decreased ejection fraction (EF) and fractional shortening (FS) and increased cardiac troponin I (cTnI), creatine kinase isoenzymes MB (CK-MB), and lactate dehydrogenase (LDH). Gsdmd-/- mice exhibited protection against LPS-induced myocardial dysfunction and had a higher survival rate. Gsdmd deficiency attenuated LPS-induced myocardial injury and cell death. Gsdmd deficiency prevented LPS-induced the increase of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in serum, as well as IL-1β and TNF-α mRNA levels in myocardium. In addition, LPS-mediated inflammatory cell infiltration into the myocardium was ameliorated and activation of NF-κB signaling pathway and the NOD-like receptor protein 3 (NLPR3) inflammasome were suppressed in Gsdmd-/- mice. Further research showed that in the myocardium of LPS-induced septic mice, GSDMD-NT enrichment in mitochondria led to mitochondrial dysfunction and reactive oxygen species (ROS) overproduction, which further regulated the activation of the NLRP3 inflammasome. In summary, our data suggest that GSDMD plays a vital role in the pathophysiology of LPS-induced myocardial dysfunction and may be a crucial target for the prevention and treatment of sepsis-induced myocardial dysfunction.

Pterostilbene Interferes With Lipopolysaccharide-Induced Myocardial Injury Through Oxidative Stress and Inflammasome Pathways

“…When the dose of LPS injected into the animal is large enough, the animal will show physiological and biochemical changes. After the use of drugs to inhibit the related myocardial inflammatory pathway, the mouse heart dysfunction caused by LPS could also be improved to a certain extent ( Abd et al, 2021 ; Dai et al, 2021a ).…”

Berberine attenuates sepsis‑induced cardiac dysfunction by upregulating the Akt/eNOS pathway in mice

“…Although it is shown to have beneficial effects ( 27 , 28 ), the therapeutic effects of berberine for sepsis-induced cardiac dysfunction have not been studied in detail to date. In the present study, mice were intraperitoneally injected with 10-mg/kg body LPS to induce cardiac dysfunction, which is a widely accepted noninvasive reliable model ( 29 , 30 ). After 6 h of LPS treatment, cardiac function was severely impaired, as evidenced by the decreases in LVEF and LVFS and the increase in myocardial injury markers.…”

Research Progress on the Mechanism of Sepsis Induced Myocardial Injury

“… 109 Activation of phosphorylated Akt also provides a promising research basis for the treatment of SIMI. 110 There is a study demonstrated that the NLRP3 inflammasomes were activated in SIMI, and TXNIP 111 as well as GSDMD 112 mediated the activation of NLRP3 inflammasomes. However, the activation of NLRP3 inflammasomes depends on the production of reactive oxygen species (ROS).…”

“…However, the activation of NLRP3 inflammasomes depends on the production of reactive oxygen species (ROS). 112 Proteomic studies have also shown that inflammatory responses in sepsis are induced by activation of the TLR4/NLRP3 signaling pathway. 113 Therefore, therapeutic strategies based on the inhibition of NLRP3 inflammasome will be the key to our study of SIMI.…”