The peptide secreted at the water to land transition in a model amphibian has antioxidant effects

• Autor(a) principal: Barbosa, Eder Alves
• Data de Publicação: 2021
• Outros Autores: Plácido, Alexandra, Moreira, Daniel C., Albuquerque, Lucas, Dematei, Anderson, Silva-Carvalho, Amandda É., Cabral, Wanessa F., Báo, Sonia N., Saldanha-Araújo, Felipe, Kuckelhaus, Selma A. S., Borges, Tatiana K., Portugal, Camila C., Socodato, Renato, Teixeira, Cátia, Lima, Filipe Camargo D. A., Batagin-Neto, Augusto [UNESP], Sebben, Antônio, Eaton, Peter, Gomes, Paula, Brand, Guilherme D., Relvas, Joao B., Kato, Massuo J., Leite, Jose Roberto S. A.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://dx.doi.org/10.1098/rspb.2021.1531; http://hdl.handle.net/11449/229957
• topic: Amphibia; antioxidant peptide; MALDI mass spectrometry imaging; oxidative stress; Pithecopus azureus; tryptophyllin

In addition to the morphophysiological changes experienced by amphibians during metamorphosis, they must also deal with a different set of environmental constraints when they shift from the water to the land. We found that Pithecopus azureus secretes a single peptide ([M + H]+ = 658.38 Da) at the developmental stage that precedes the onset of terrestrial behaviour. De novo peptide and cDNA sequencing revealed that the peptide, named PaT-2, is expressed in tandem and is a member of the tryptophyllins family. In silico studies allowed us to identify the position of reactive sites and infer possible antioxidant mechanisms of the compounds. Cell-based assays confirmed the predicted antioxidant activity in mammalian microglia and neuroblast cells. The potential neuroprotective effect of PaT-2 was further corroborated in FRET-based live cell imaging assays, where the peptide prevented lipopolysaccharide-induced ROS production and glutamate release in human microglia. In summary, PaT-2 is the first peptide expressed during the ontogeny of P. azureus, right before the metamorphosing froglet leaves the aquatic environment to occupy terrestrial habitats. The antioxidant activity of PaT-2, predicted by in silico analyses and confirmed by cell-based assays, might be relevant for the protection of the skin of P. azureus adults against increased O 2 levels and UV exposure on land compared with aquatic environments.