Ameliorative Effect of Erjing Pills on Retinal Damage in Rats with Diabetic Retinopathy.

Background

Diabetic retinopathy (DR) is one of the major complications of diabetes mellitus. EJPs (Erjing Pills) are believed in Traditional Chinese Medicine to have the effects of a nourishing essence and a brightening of the eyes, but the specific effect on DR remains unclear. This study aims to investigate the therapeutic effects and underlying mechanisms of EJPs on DR.

Methods

The chemical profile of EJPs was characterized by UHPLC-MS. Network pharmacology and molecular docking were employed to predict its active ingredients and potential targets. A DR rat model was induced by streptozotocin. Retinal morphology and function were assessed by OCT, FFA, and H&E staining. The expressions of proteins and mRNAs related to the AGE-RAGE pathway, oxidative stress, inflammation, and tight junctions were detected by Western blot, qPCR, and ELISA.

Results

LC-MS and network pharmacology analysis identified 638 common targets between EJPs and DR, with core targets including SRC, AKT1, and MAPK1, primarily enriched in the AGE-RAGE signaling pathway. Molecular docking confirmed strong binding (binding energy < -5.0 kcal/mol) between key EJP constituents and core targets. In vivo, EJP treatment significantly alleviated retinal vascular leakage, improved retinal thickness, and alleviated histopathological damage. In addition, EJPs downregulated the AGEs-RAGE/NF-κB axis and pro-inflammatory cytokines while enhancing antioxidant defenses and tight junction proteins in the retinas of DR rats.

Conclusions

EJPs ameliorate DR by protecting the blood-retinal barrier and modulating the AGE-RAGE/oxidative stress/inflammation network, demonstrating a multi-component, multi-target, and multi-pathway mechanism. This study provides a mechanistic basis for the potential application of EJPs in DR management.