The present invention relates to the treatment of infectious diseases. In this study, the inventors identified the potential protective mechanisms involved in the maintenance of cerebrovascular integrity during bacterial infection, the inventors performed RNA analysis of primary endothelial cells isolated from human dermal (HDMECs) or brain (HBMECs) microvessels, which were left uninfected or were infected in vitro with meningococci. They found 40 genes specifically regulated in cerebral endothelial cells upon infection and notably ANGPTL4. They showed that, in the context of sepsis, ANGPTL4 is a major barrier-stabilizing protein conferring protection against bacterial infection. They also demonstrated the potential of ANGPTL4 (or derived peptide) as adjuvant treatment to reduce bacterial-induced vascular dysfunction and mortality. Thus, the present invention relates to peptide derived from the protein ANGPTL4 and their used in the treatment of infectious diseases.