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bioRxiv · 10.1101/2023.07.07.548146

Cathelicidin downregulates neurotensin and substance P hippocampal levels

Flores, I. P.·Ariga, S. K.·Barbeiro, H. V.·Barbeiro, D. F.·Pinheiro Da Silva, F.
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Abstract

BackgroundSepsis 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. MethodsMice were submitted to cecal ligation and puncture and the protein levels of neurotensin, substance P, oxytocin and {beta}-endorphin were evaluated in the brain. ResultsWe 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. ConclusionsThe 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.

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Flores, I. P., Ariga, S. K., Barbeiro, H. V., Barbeiro, D. F., Pinheiro Da Silva, F.. 2023-07-09. Cathelicidin downregulates neurotensin and substance P hippocampal levels. https://doi.org/10.1101/2023.07.07.548146

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