Hirudo extract ameliorates proliferative vitreoretinopathy by promoting autophagy and attenuating the THBS2/PI3K/Akt pathway.

Epithelial‒mesenchymal transition (EMT) in retinal pigment epithelial (RPE) cells is believed to play a key role in the pathogenesis of proliferative vitreoretinopathy (PVR). The ability of Hirudo to promote blood flow and dispel blood stasis may be related to its anti-EMT effects. Through the use of a network pharmacology method, the mechanism by which Hirudo treats PVR was investigated in this study, and the findings were confirmed through in vitro cellular tests. The targets and pathways of the active compounds of Hirudo against PVR were predicted via a network pharmacology technique. ARPE-19 cells were treated with several doses of Hirudo extract, that did or did not contain TGF-β2 (10 ng/mL). CCK-8, wound healing, and Transwell assays were performed to detect the viability, migration, and invasion of the cells. Immunofluorescence staining was used to detect F-actin expression. Autophagy was observed via transmission electron microscopy. The mRNA expression of MMP9, N-cadherin, vimentin, THBS2, PI3K, and Akt was measured via RT‒qPCR. Western blotting was used to detect the protein expression of MMP9, N-cadherin, vimentin, LC3B, THBS2, PI3K, p-PI3K, Akt, and p-Akt. The prediction yielded a total of 546 potential targets, 875 PVR-associated disease targets, and 22 Hirudo-PVR cross-targets involving VWF, THBS2, TP53, and IGF1R, and it was inferred that the mechanism might be related to the PI3K‒Akt signaling pathway. After APRE-19 cells were treated with TGF-β2, cell migration, invasion, and viability increased. Additionally, the expression of F-actin, MMP9, N-cadherin, vimentin, THBS2, PI3K, p-PI3K, Akt, and p-Akt was upregulated. Hirudo extract counteracted the effects of TGF-β2 among APRE-19 cells. The promotion of autophagy in APRE-19 cells by TGF-β2 is highlighted, as evidenced by an increase in the LC3II/LC3I ratio. The autophagy-promoting effect of TGF-β2 on APRE-19 cells was further enhanced by Hirudo extract. Hirudo extract improved PVR by promoting autophagy and inhibiting the EMT process, and the mechanism may be related to the regulation of the THBS2/PI3K/Akt pathway.