ArticleJournal of natural products2015
Inhibition of Human Prolyl Oligopeptidase Activity by the Cyclotide Psysol 2 Isolated from Psychotria solitudinum.
Article in Journal of natural products, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers.
What it found
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
19 citing papers in PubMed, 49 citations in OpenAlex.
- Tropical psychotria plants are a rich source for peptide inhibitors of human prolyl oligopeptidase.Natural products and bioprospecting · 2026Article
- Small and Versatile Cyclotides as Anti-infective Agents.ACS infectious diseases · 2025Review
- Peptide hormones in plants.Molecular horticulture · 2025Review
- Unveiling mechanisms of antimicrobial peptide: Actions beyond the membranes disruption.Heliyon · 2024Review
- Plant proteins, peptides, and non-protein amino acids: Toxicity, sources, and analysis.Heliyon · 2024Review
- Discovery of the cyclotide caripe 11 as a ligand of the cholecystokinin-2 receptor.Scientific reports · 2022Article
- Effects of a plant cyclotide on conformational dynamics and destabilization of β-amyloid fibrils through molecular dynamics simulations.Frontiers in molecular biosciences · 2022Article
- In vitro antiviral activity of peptide-rich extracts from seven Nigerian plants against three non-polio enterovirus species C serotypes.Virology journal · 2021Article
- Cyclotides from BrazilianJournal of natural products · 2021Article
- Computer-Aided Drug Discovery Identifies Alkaloid Inhibitors of Parkinson's Disease Associated Protein, Prolyl Oligopeptidase.Evidence-based complementary and alternative medicine : eCAM · 2021Article
- Cyclotides Isolated From Violet Plants of Cameroon Are Inhibitors of Human Prolyl Oligopeptidase.Frontiers in pharmacology · 2021Article
- Discovery of a Beetroot Protease Inhibitor to Identify and Classify Plant-Derived Cystine Knot Peptides.Journal of natural products · 2020Article
- Isolation of Cysteine-Rich Peptides fromBiomolecules · 2020Article
- Peptide-based protease inhibitors from plants.Drug discovery today · 2019Review
- The Potential of the Cyclotide Scaffold for Drug Development.Biomedicines · 2019Review
- Plant cystine-knot peptides: pharmacological perspectives.British journal of clinical pharmacology · 2017Review
- Chemical Proteomics for Target Discovery of Head-to-Tail Cyclized Mini-Proteins.Frontiers in chemistry · 2017Article
- Cyclotides Isolated from an Ipecac Root Extract Antagonize the Corticotropin Releasing Factor Type 1 Receptor.Frontiers in pharmacology · 2017Article
- Peptidomics of Circular Cysteine-Rich Plant Peptides: Analysis of the Diversity of Cyclotides from Viola tricolor by Transcriptome and Proteome Mining.Journal of proteome research · 2015Article
Corrections and comments
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Authors and funding
7 authors at 3 institutions in 3 countries.
Funding
Abstract
Cyclotides are head-to-tail cyclized peptides comprising a stabilizing cystine-knot motif. To date, they are well known for their diverse bioactivities such as anti-HIV and immunosuppressive properties. Yet little is known about specific molecular mechanisms, in particular the interaction of cyclotides with cellular protein targets. Native and synthetic cyclotide-like peptides from Momordica plants are potent and selective inhibitors of different serine-type proteinases such as trypsin, chymotrypsin, matriptase, and tryptase-beta. This study describes the bioactivity-guided isolation of a cyclotide from Psychotria solitudinum as an inhibitor of another serine-type protease, namely, the human prolyl oligopeptidase (POP). Analysis of the inhibitory potency of Psychotria extracts and subsequent fractionation by liquid chromatography yielded the isolated peptide psysol 2 (1), which exhibited an IC50 of 25 μM. In addition the prototypical cyclotide kalata B1 inhibited POP activity with an IC50 of 5.6 μM. The inhibitory activity appeared to be selective for POP, since neither psysol 2 nor kalata B1 were able to inhibit the proteolytic activity of trypsin or chymotrypsin. The enzyme POP is well known for its role in memory and learning processes, and it is currently being considered as a promising therapeutic target for the cognitive deficits associated with several psychiatric and neurodegenerative diseases, such as schizophrenia and Parkinson's disease. In the context of discovery and development of POP inhibitors with beneficial ADME properties, cyclotides may be suitable starting points considering their stability in biological fluids and possible oral bioavailability.
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Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.