Biological characterization of natural peptide BcI-1003 from Boana cordobae (anura): role in Alzheimer’s Disease and microbial infections.

Nature continues to be one of the most important sources of molecules for the development of novel therapeutic agents. The skin of anuran’s (frogs and toads) is a rich source of peptides with a great importance in the search of bioactive agents applying to human health. Alzheimer's disease (AD) is a complex disease associated with numerous pathological pathways, making their simultaneous modulation necessary. On the other hand, the increasing bacterial resistance against conventional antibiotics has made it essential to search for new antimicrobial drugs with different modes of action. Here in we report the natural peptide BcI-1003, isolated from Boana cordobae amphibian skin, as an agent capable to act on three key therapeutic targets of AD, inhibiting the activity of BChE (IC 50  = 669 µM) and MAO-B (IC 50  = 570 µM) enzymes, and showing a powerful and rapid antioxidant activity (EC 50  = 7.24 µM). Besides, BcI-1003 showed antimicrobial activity against clinically drug-resistant gram-positive and gram-negative bacterial strains, with MIC values ranging from 8 to 127 µM against Staphylococcus aureus MR-1; S. aureus MR-2 and Escherichia coli MDR-1.