Cathelicidin downregulates neurotensin and substance P hippocampal levels

Background Sepsis is a life-threatening condition and septic encephalopathy is an early and frequent manifestation of this disease. Antimicrobial peptides are important components of innate immunity playing a crucial role during bacterial infections. Here, we investigate the protein levels of several neuropeptides in CRAMP-deficient and wild-type mice, in healthy conditions and following experimental sepsis. Methods Mice were submitted to cecal ligation and puncture and the protein levels of neurotensin, substance P, oxytocin and β-endorphin were evaluated in the brain. Results We found that CRAMP-deficient mice produce significantly less neurotensin and substance P than wild-type mice in the hippocampus, both before and 24 hours following experimental sepsis, but not 15 days post-septic shock. Conclusions The hippocampus is a complex structure, highly vulnerable during sepsis. The role of antimicrobial peptides and their interplay with neuropeptides should be further evaluated in this scenario.