Ginsenoside Rg1 restores neural stem cell homeostasis in simulated microgravity via MAPK/AKT-vimentin axis

Microgravity-induced neural dysfunction poses a critical risk during long-term spaceflight. However, the intrinsic mechanosensing mechanisms by which neural stem cells (NSCs) decode gravitational loss into biochemical responses and effective multi-target countermeasures remain elusive. This study aims to clarify the protective mechanism of ginsenoside Rg 1 (Rg 1 ) on simulated microgravity (SMG)-damaged C17.2 mouse neural stem cells (NSCs) by targeting vimentin serine 56 (Ser56) phosphorylation and the mitogen-activated protein kinase (MAPK)/protein kinase B (AKT) signaling network, and verify its “multi-pathway synergy” characteristic guided by traditional Chinese medicine (TCM) theory. An SMG environment was established using a random positioning machine (RPM). The safe and effective concentration of Rg 1 (40 μmol/L) was screened using the cell counting kit-8 (CCK-8) assay. Mitochondrial function and cytoskeletal structure were evaluated via transmission electron microscopy and F-actin staining. Flow cytometry, Western blotting, quantitative real-time polymerase chain reaction, combined with global proteomics, phosphoproteomics, and extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor experiments, were employed to dissect the action mechanism of Rg 1 . First, SMG inhibited NSC differentiation, disrupted cytoskeletal structure, and induced apoptosis, with the core mechanism being the impairment of cytoskeletal architecture and its dynamic phosphorylation network. Second, 40 μmol/L Rg 1 restored F-actin continuity, rescued neurodifferentiation function, and inhibited apoptosis; these effects relied on the activation of the MAPK/AKT kinase network and the specific rescue of vimentin Ser56 phosphorylation. Third, Rg 1 regulated the kinase-intermediate filament (IF) axis through “ERK1/2-dependent and independent” dual pathways rather than single-target intervention. Notably, its regulatory effect directly acted on post-translational modification (phosphorylation) instead of merely altering protein abundance. Rg 1 restores cytoskeletal integrity and neurogenesis in C17.2 NSCs under SMG by regulating the kinase-IF axis. This modern molecular evidence bridges TCM theory with mechanobiology, confirming Rg 1 as a promising TCM candidate for protecting astronaut brain health. It exemplifies the “holistic regulation” of TCM and provides a paradigm for the application of TCM in space medicine.