The invention relates to the technical field of 
biomedicine, in particular to tetranectin-mimicking 
peptide TNP and its application in treating diseases caused by the release of HMGB1 from vascular endothelial cells.  The sequence of the acetylated tetranectin mimetic 
peptide at the 
nitrogen end is Ac‑QPDGGKTENCAVLSGAANGKWFDKRCRDK‑
biotin. The acetylated tetranectin mimetic 
peptide TNP can effectively prevent the 
hydrolysis of TNP and prolong its half-life to improve the biological 
efficacy of the 
drug. TNP is in use  When preparing drugs for the treatment of 
sepsis and other diseases, it can effectively inhibit the release of HMGB1 from vascular endothelial cells, reduce the concentration of 
extracellular HMGB1, and reduce the death rate of septic mice, and can almost completely block renal 
ischemia-reperfusion in mice.  Changes in 
plasma urea nitrogen and 
creatinine can reduce renal tubular 
necrosis after 
ischemia, achieve the purpose of treating 
acute kidney injury, and provide a new way for the diagnosis and treatment of human diseases caused by the release of HMGB1 from vascular endothelial cells.