Role of TXNIP/NLRP3 in sepsis-induced myocardial dysfunction

Myocardial injury is one of the main symptoms of sepsis. However, the mechanisms underlying sepsis‑induced myocardial dysfunction remain unclear. In the present study, the concentration of cardiac troponin T (CTnT) in serum was measured using an enzyme‑linked immunosorbent assay kit. The levels of interleukin (IL)‑1β and IL‑18 were assessed by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) analysis and the level of malondialdehyde (MDA) was determined using a corresponding kit. Myocardial pathology was analyzed via hematoxylin and eosin staining. RT‑qPCR analysis and western blotting and/or immunohistochemistry were used to quantify the expression levels of thioredoxin‑interacting protein (TNXIP), NOD‑like receptor pyrin domain containing 3 (NLRP3), cleaved caspase‑1, caspase‑1, catalase and manganese‑superoxide dismutase (MnSOD). The viability of cells was determined using a cell counting kit‑8. Apoptosis and reactive oxygen species (ROS) were examined using flow cytometry. Models of sepsis‑induced myocardial injury were successfully established; evidence included increases in the levels of CTnT, IL‑1β, IL‑18 and MDA and myocardial tissue damage in vivo, and decreased cell viability and improvements in IL‑1β and IL‑18 in vitro. The levels of TXNIP, NLRP3 and cleaved caspase‑1 were upregulated in the sepsis models. Small interfering RNA targeting TNXNIP (siTXNIP) increased cell viability, reduced the apoptotic rate and attenuated the release of IL‑1β and IL‑18. The levels of TXNIP, NLRP3 and cleaved caspase‑1 and production of ROS were suppressed by siTXNIP, accompanied by increases in catalase and MnSOD. TXNIP/NLRP3 serves an important role in the development of sepsis‑induced myocardial damage.