Ginsenoside Rg2 Targeting PDHE1 α to Improve High Glucose-Induced Hippocampal Neuronal Damage Based on CETSA...

To explore the effect of ginsenoside Rg2 (G-Rg2) targeting pyruvate dehydrogenase E1 component subunit alpha (PDHE1 α) on its downstream energy metabolism to repair damaged hippocampal neurons.

The binding affinity between G-Rg2 and PDHE1 α was obtained by molecular docking (MD) and surface plasmon resonance (SPR). The thermal stability of Rg2 binding to PDHE1 α protein was evaluated by cellular thermal shift assay (CETSA), and the binding of Rg2 to PDHE1 α protein was further confirmed by isothermal dose-response curve. The mouse hippocampal neuronal cell line (HT22) was divided into 2 main groups: a PDHE1 α transfection control group and a PDHE1 α silencing group. Each main group was further subdivided into 3 treatment groups: a normal group (untreated), a high-glucose injury model group, and a Rg2 adminis0tration group. The downstream molecules and metabolites of PDHE1 α such as adenosine triphosphate (ATP), reactive oxygen species (ROS), acetyl coenzyme A (acetyl-CoA), and the oxidized/reduced ratio of nicotinamide adenine dinucleotide (NAD⁺/NADH ratio) were measured. The energy metabolism patterns of each group were analyzed using the hippocampus bioenergy analyzer to further confirm the interaction between Rg2 and PDHE1 α and the biological effect of the interaction.

MD and SPR techniques found that G-Rg2 directly bound to the target protein PDHE1 α and significantly improved its thermal stability. Isothermal dose-response results were consistent with these findings. The high glucose-induced HT22 cell injury model showed abnormal phenotypes including decreased PDH enzyme activity, increased ROS, decreased ATP production, an imbalanced NAD⁺/NADH ratio, decreased acetyl-CoA production, and altered glucose metabolism. After G-Rg2 intervention, different degrees of metabolic recovery were observed (P<0.05 or P<0.01). When PDHE1 α was silenced, the silenced group showed a similar metabolic damage phenotype induced by high glucose, compared with the normal group. After PDHE1 α silencing, glucose modeling further aggravated the damage. In the injury model of PDHE1 α silencing with glucose induction, G-Rg2 showed different degrees of metabolic recovery after intervention (P<0.05 or P<0.01).

PDHE1 α can be used as a direct cell target for G-Rg2 to treat high glucose-injured neurons, which can provide data support for the protein activity of PDHE1 α and the pharmacological activity of G-Rg2 in improving neurodegenerative diseases.