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Updated: Jun 20, 2025

Construction of Cyclic Cell-Penetrating Peptides for Enhanced Penetration of Biological Barriers
Published on: September 19, 2022
Predicting Peptide Permeability Across Diverse Barriers: A Systematic Investigation
Xiaorong Tan1, Qianhui Liu1, Yanpeng Fang1
1Xiangya School of Pharmaceutical Sciences, Central South University, Changsha 410083, China.
This study developed novel machine learning models, including a graph neural network (GNN) framework, to accurately predict peptide permeability. These tools enhance drug delivery and peptide drug discovery by assessing cell membrane penetration.
Area of Science:
- Pharmacology and Drug Delivery
- Computational Chemistry
- Biotechnology
Background:
- Peptide therapeutics show great potential but face challenges with cell membrane permeability.
- Poor permeability limits intracellular delivery and oral drug development for peptides.
Purpose of the Study:
- To develop predictive models for peptide permeability using graph neural networks (GNNs) and machine learning.
- To systematically evaluate peptide permeability across diverse peptide types and cell lines.
- To identify key molecular features influencing peptide permeability.
Main Methods:
- Developed a novel GNN framework and machine learning algorithms for peptide permeability prediction.
- Evaluated models on natural, modified, linear, and cyclic peptides using Caco-2, RRCK, and PAMPA assays.
- Interpreted molecular structural features impacting permeability and the effects of cell lines and peptide modifications.
Main Results:
- Achieved high predictive accuracy (R² up to 0.708) for linear and cyclic peptides in Caco-2 and RRCK cell lines.
- GNN framework demonstrated superior performance with larger datasets, improving cyclic peptide prediction in PAMPA by ~0.32 R².
- Successfully identified critical molecular features and factors influencing peptide permeability.
Conclusions:
- The developed GNN framework offers a rapid and reliable strategy for assessing peptide permeability.
- These models aid in optimizing peptide drug delivery, preselecting peptides, and designing targeted peptide materials.
- The models are accessible via the user-friendly KNIME platform for broader research application.
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