Regulation of Nrf2/A20/eEF1A2 Axis by Ginsenoside Rb1: A Key Pathway in Alleviating Cerebral Ischemia-Reperfusion Injury.

Abstract

Cerebral ischemia-reperfusion injury (CIRI) is a prevalent neurological disorder, characterized by the oxidative stress and inflammatory response induced during the ischemia-reperfusion process, leading to significant damage to brain cells. Ginsenoside Rb1, a natural medicinal ingredient, possesses potential neuroprotective effects. This study aims to investigate the mechanism of action of ginsenoside Rb1 in CIRI and its protective effects on brain injury. We utilized a mouse CIRI model and randomly divided the mice into control group, CIRI group, and ginsenoside Rb1 treatment group. The effects of Rb1 on brain tissue damage, apoptosis, expression of inflammatory factors, and pyroptotic cell numbers in CIRI mice were observed through triphenyl tetrazolium chloride (TTC) staining, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, real-time reverse transcription polymerase chain reaction (qRT-PCR), and electron microscopy. In a cell model, the regulatory effect of Rb1 on oxygen-glucose deprivation/reperfusion (OGD/R)-induced HT22 cell pyroptosis via the nuclear respiratoty factor 2/tumor necrosis factor-α (TNF-α)-induced Protein 3 (TNFAIP3, aka A20)/eukaryotic translation elongation factor 1A2 (Nrf2/A20/eEF1A2) axis was detected using Western blot and TUNEL staining. Additionally, the impact of Nrf2 inhibitor ML385 and eEF1A2 overexpression on the neuroprotective effect of Rb1 was assessed. Using the comprehensive experimental methods mentioned above, the neuroprotective mechanism of Rb1 in CIRI was thoroughly evaluated. Our findings demonstrate that treatment with ginsenoside Rb1 alleviated behavioral deficits induced by CIRI and reduced pathological damage in brain tissue. Furthermore, ginsenoside Rb1 treatment notably decreased oxidative stress and the inflammatory response induced by CIRI, leading to lower levels of inflammatory factors (p < 0.05). Further experimental results indicated that ginsenoside Rb1 promoted antioxidant and anti-inflammatory responses by regulating the activity of the Nrf2/A20/eEF1A2 axis. Additionally, ginsenoside Rb1 inhibited the activation of the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome, thereby reducing the release of inflammatory factors and the occurrence of cell apoptosis. Our study results suggest that ginsenoside Rb1 exerts neuroprotective effects and alleviates brain injury induced by CIRI by regulating the Nrf2/A20/eEF1A2 axis and inhibiting the activation of the NLRP3 inflammasome. These findings provide new treatment insights for CIRI and support ginsenoside Rb1's development as a therapeutic drug. However, despite the promising nature of our findings, further research is required to validate these discoveries and explore the feasibility and safety of ginsenoside Rb1 in clinical applications. We hope that our study can provide new directions and strategies for the treatment and prevention of CIRI, contributing to the development of neuroprotective drugs.