Mechanism of Tetrastigma hemsleyanum extracts on diabetic retinopathy based on network pharmacology and experimental verification

Abstract

Introduction

Diabetic retinopathy (DR) is a prevalent ocular complication of diabetes, with advanced stages potentially leading to blindness. Tetrastigma hemsleyanum (San ye qing, SYQ) has traditionally been employed in addressing ailments such as fever, asthma, hepatitis, infantile febrile seizures, pneumonia, rheumatism, and sore throats. Initial animal studies have suggested that SYQ may significantly curb the progression of DR. This study utilized network pharmacology to explore the mechanism of Tetrastigma hemsleyanum (San ye qing, SYQ) in diabetes retinopathy (DR), with subsequent validation through molecular docking and experiments.

Methods

Male C57BL/6 J mice were applied to establish a type Ⅰ diabetes model. Hemoxylin & eosin staining and western blotting were then used to evaluate the efficacy of SYQ. Databases including Swiss Target Prediction, GeneCards, and DisGeNet were used to filter targets related to DR. The STRING database and Cytoscape software were used to create a protein-protein interaction network. The Metascape database was used to conduct Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses of mutual targets. The active compounds were subjected to molecular docking with core targets using AutoDock software, and the predicted outcomes from network pharmacology were verified in vitro. Tube formation and migration experiments were conducted to evaluate the anti-angiogenic effect and mechanism of SYQ on high glucose-induced EA.hy926 cells.

Results

SYQ demonstrated an inhibitory effect on angiogenesis within the DR model and decreased the expression of proteins related to angiogenesis. Network pharmacology analyses revealed that SYQ targeted 127 proteins, with implications for pathways including the HIF-1 signaling pathway. Molecular docking illuminated that β-sitosterol, Procyanidin-B1, and Emodion-1-O-β-d-glucopyranoside exhibited strong binding affinities with AKT1 core target proteins. In vitro experiments corroborated that SYQ diminished tube formation and migration of EA.hy926 cells under high glucose conditions, in a dose-dependent manner. The pro-angiogenic influence of an AKT1 agonist was counteracted by SYQ. Additionally, administration of SYQ led to reduced expression of p-AKT, HIF-1, and angiogenesis-related proteins, suggesting an inhibitory mechanism via AKT1 against high glucose-induced angiogenesis. These observations confirmed the network pharmacology insights.

Discussion

SYQ emerged as a potential therapeutic agent for DR, primarily by inhibiting angiogenesis. Its anti-angiogenetic effect was mediated via the AKT1/HIF-1/VEGF pathway, indicating a promising avenue for further research and potential clinical application in DR management.