LPS-Induced Sepsis Model Establishment

A total of 120 clean male C57BL/6 mice (aged 8–10 weeks, weighing 25–29 g) purchased from Beijing HFK Bioscience (Beijing, P.R. China) were included in the current study. After adaptive feeding for 1 week, the mice were injected with PBS and regarded as the controls, while the remaining mice were treated with LPS (15 mg/kg, Sigma-Aldrich, St. Louis, USA, cat. no. L2880) to simulate the pathological changes associated with sepsis in vivo. 1 h after LPS injection, the LPS-exposed mice were further injected with 100 μL lentivirus expressing shRNA against TLR2 (sh-TLR2; 10⁸ PFU; Merck, Darmstadt, Germany), 100 μL lentivirus overexpressing TLR2 (10⁸ PFU; Merck, Darmstadt, Germany), 0.4 pmol/μL miR-410-3p agomir (0.5 mL/10 g; Merck, Darmstadt, Germany), as well as their corresponding NCs (pcDNA3.1, sh-NC and agomir-NC) via the tail vein. 24 h later, the serum and heart of mice were collected for follow-up analysis. The serum endotoxin levels were determined by dynamic turbidimetry using a limulus test kit to verify whether the sepsis model had been successfully established. A total of 12 successful modeled mice were selected per treatment regimen.