An atlas of O-linked glycosylation on peptide hormones reveals diverse biological roles

Abstract

Peptide hormones and neuropeptides encompass a large class of bioactive peptides that regulate physiological processes like anxiety, blood glucose, appetite, inflammation and blood pressure. Here, we execute a focused discovery strategy to provide an extensive map of Oglycans on peptide hormones. We find that almost one third of the 279 classified peptide hormones carry O-glycans. Many of the identified O-glycosites are conserved and are predicted to serve roles in proprotein processing, receptor interaction, biodistribution and biostability. We demonstrate that O-glycans positioned within the receptor binding motifs of members of the neuropeptide Y and glucagon families modulate receptor activation properties and substantially extend peptide half-lives. Our study highlights the importance of Oglycosylation in the biology of peptide hormones, and our map of O-glycosites in this large class of biomolecules serves as a discovery platform for an important class of molecules with potential opportunities for drug designs.

Synthesis, Physicochemical Characterization, In Vitro 2D/3D Human Cell Culture, and In Vitro Aerosol Dispersion Performance of Advanced Spray Dried and Co-Spray Dried Angiotensin (1—7) Peptide and PNA5 with Trehalose as Microparticles/Nanoparticles for Targeted Respiratory Delivery as Dry Powder Inhalers

“…Thus, several strategies have been successfully employed to improve the native peptides' stability, circulation time, safety, immune tolerance, efficacy, and biodistribution. Some of these strategies are the use of unnatural amino acids, modifications such as lipidation, PEGylation, conjugation to antibodies, and stapled peptides [12][13][14]. One of the promising strategies is glycosylation, an effective synthetic approach that introduces carbohydrate moieties to peptides [15].…”

“…As Ang (1-7) is a native bioactive peptide with all above-mentioned therapeutic potential, our group developed a derivative of it via the glycosylation strategy. Glycopeptide drugs based on angiotensin hormones benefit from an intrinsic affinity for their target receptors; they show high biological activity and target specificity at their intended receptors; have low toxicity; and produce greatly reduced (liver mediated) drug-drug interactions relative to classical small molecule drugs [12,15,20,21]. Glycosylation of Ang (1-7) (DRVYIHP) replaces the seventh residue (proline) with serine and has a glucoside attached to the serine, and is amidated at the C-terminus resulting in Ang-1-6-Ser-O-Glu-NH 2 (PNA5) [15,22].…”

The half-life of the bone-derived hormone osteocalcin is regulated through O-glycosylation in mice, but not in humans

“…The results presented above suggest that O- glycosylation is not regulating the processing of pro-OCN by furin or the secretion of mature OCN by osteoblasts. It was recently observed that O -glycosylation can also increase the stability of some peptide hormones in the circulation by preventing proteolytic degradation ( Hansen et al, 2019 ; Madsen et al, 2020 ). We therefore aimed at testing the impact of O -glycosylation on OCN half-life in plasma.…”

Expanding the Chondroitin Sulfate Glycoproteome — But How Far?

“…In glycobiology, mass spectrometry-based strategies for investigating protein glycosylation (glycoproteomics) have become an increasingly important tool ( Nilsson et al, 2009 ; Thaysen-Andersen et al, 2016 ; Narimatsu et al, 2018 ). Such strategies, well-covered in excellent reviews, are typically based on enrichment of glycopeptides and subsequent analysis with nLC-MS/MS to provide site-specific information of N - and O -glycans ( Nilsson, 2016 ; Darula and Medzihradszky, 2018 ; Madsen et al, 2020 ; Chernykh et al, 2021 ). To further develop this concept, we established a glycoproteomic protocol for global characterization of CS-glycopeptides in human urine and cerebrospinal fluid (CSF) ( Noborn et al, 2015 ; Noborn et al, 2021 ).…”