title: Cell-Penetrating Ability of Peptide Hormones: Key Role of Glycosaminoglycans Clustering.
abstract: Over the last two decades, the potential usage of cell-penetrating peptides (CPPs) for the intracellular delivery of various molecules has prompted the identification of novel peptidic identities. However, cytotoxic effects and unpredicted immunological responses have often limited the use of various CPP sequences in the clinic. To overcome these issues, the usage of endogenous peptides appears as an appropriate alternative approach. The hormone pituitary adenylate-cyclase-activating polypeptide (PACAP38) has been recently identified as a novel and very efficient CPP. This 38-residue polycationic peptide is a member of the secretin/glucagon/growth hormone-releasing hormone (GHRH) superfamily, with which PACAP38 shares high structural and conformational homologies. In this study, we evaluated the cell-penetrating ability of cationic peptide hormones in the context of the expression of cell surface glycosaminoglycans (GAGs). Our results indicated that among all peptides evaluated, PACAP38 was unique for its potent efficiency of cellular uptake. Interestingly, the abilities of the peptides to reach the intracellular space did not correlate with their binding affinities to sulfated GAGs, but rather to their capacity to clustered heparin in vitro. This study demonstrates that the uptake efficiency of a given cationic CPP does not necessarily correlate with its affinity to sulfated GAGs and that its ability to cluster GAGs should be considered for the identification of novel peptidic sequences with potent cellular penetrating properties.
authors.affiliation: Department of Chemistry, PharmaQAM, University of Québec in Montréal, Montréal, QC H3C 3P8, Canada. tchoumi_neree.armelle@courrier.uqam.ca.|Quebec Network for Research on Protein Function, Structure and Engineering, PROTEO, Quebec City, QC G1V 0A6, Canada. tchoumi_neree.armelle@courrier.uqam.ca.
authors.forename: Armelle Tchoumi
authors.initials: AT
authors.lastname: Neree
authors.affiliation: Department of Chemistry, PharmaQAM, University of Québec in Montréal, Montréal, QC H3C 3P8, Canada. phuong.t.ngn@gmail.com.|Quebec Network for Research on Protein Function, Structure and Engineering, PROTEO, Quebec City, QC G1V 0A6, Canada. phuong.t.ngn@gmail.com.
authors.forename: Phuong Trang
authors.initials: PT
authors.lastname: Nguyen
authors.affiliation: Department of Chemistry, PharmaQAM, University of Québec in Montréal, Montréal, QC H3C 3P8, Canada. bourgault.steve@uqam.ca.|Quebec Network for Research on Protein Function, Structure and Engineering, PROTEO, Quebec City, QC G1V 0A6, Canada. bourgault.steve@uqam.ca.
authors.forename: Steve
authors.initials: S
authors.lastname: Bourgault
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D057846:Cell-Penetrating Peptides / Q000737:chemistry / Q000378:metabolism*; D003412:Cricetulus; D006025:Glycosaminoglycans / Q000378:metabolism; D006493:Heparin / Q000378:metabolism; D008024:Ligands; D008969:Molecular Sequence Data; D036361:Peptide Hormones / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding; D011487:Protein Conformation; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism
chemical_list: D057846:Cell-Penetrating Peptides; D006025:Glycosaminoglycans; D008024:Ligands; D036361:Peptide Hormones; D043562:Receptors, G-Protein-Coupled; D006493:Heparin
keywords: PACAP; cell-penetrating peptides; cellular uptake; glucagon; glycosaminoglycans; peptide hormones; pituitary adenylate-cyclase-activating polypeptide; secretin