Elevated peripheral glutamate and upregulated expression of NMDA receptor NR1 subunit in insomnia disorder

Jujuboside A in ameliorating insomnia in mice via GABAergic modulation of the PVT

ETHNOPHARMACOLOGICAL RELEVANCE

Ziziphus jujuba var. spinosa (Bunge) Hu ex H. F. Chow (ZSS), a traditional Chinese medicinal herb, has been historically used to treat insomnia and neurological disorders. Jujuboside A, a triterpenoid saponin isolated from ZSS, represents its core bioactive component with purported sedative properties, yet its mechanism of action remains underexplored.

AIM OF THE STUDY

To validate the anti-insomnia efficacy of Jujuboside A and elucidate its GABAergic regulatory mechanisms through integrated in vivo and in vitro approaches.

MATERIALS AND METHODS

A chronic sleep deprivation mouse model was established using modified multi-platform water environment. Behavioral assessments (open-field test, pentobarbital-induced sleep test) were combined with histopathological analysis (H&E staining), flow cytometry (apoptosis), ELISA (GABA/Glu quantification), and Western blot (GABA A/GABA B, NMDA/AMPA receptors). Pharmacological inhibition of GABA signaling was performed using GABA-IN-1.

RESULTS

Jujuboside A significantly shortened sleep latency and prolonged sleep duration vs. model group. Histopathology revealed Jujuboside A-mediated restoration of hippocampal neuronal density and mitigation of nuclear pyknosis. Jujuboside An upregulated GABA levels while suppressing Glu and neuronal apoptosis, with concomitant increases in GABA A and GABA B receptor expression. Crucially, GABA-IN-1 abolished these therapeutic effects, confirming GABA dependency.

CONCLUSIONS

Jujuboside A ameliorates insomnia by restoring GABA/Glu homeostasis and enhancing GABA receptor expression, thereby validating ZSS's traditional use through modern pharmacological evidence.