Efficacy of Shouzhangshen (Rhizoma Gymnadeniae Crassinervidis) extract against acute high altitude hypoxia-induced brain injury in mice.

Objective: To evaluate the protective effect of Shouzhangshen (Rhizoma Gymnadeniae Crassinervidis) extract against acute high altitude hypoxia-induced brain injury in mice.

Methods: Sixty C57BL/6J mice were selected and assigned to six groups (n = 10): normal control group, low-pressure hypoxia group, positive control group (dexamethasone 500 mg/kg), and three groups treated with Shouzhangshen extract (250, 500, and 750 mg/kg, respectively). The Morris water maze test was performed to evaluate alterations in spatial learning and memory deficits. Nissl staining was performed to detect Nissl bodies and neuron damage. Hypoxia-inducible factor (HIF)-1α, interleukin (IL)-1β, tumor necrosis factor (TNF)-α, vascular endothelial growth factor (VEGF), and malondialdehyde (MDA) expression in brain tissue and serum, as well as superoxide dismutase (SOD) and glutathione (GSH) activity in brain tissues were measured by enzyme-linked immunosorbent assays, quantitative real-time-polymerase chain reaction and western blots.

Results: The Morris water maze test results showed that Shouzhangshen extract can significantly reduce the latency and swimming distance to escape onto a visible platform, increase neuron density and hierarchy and the number of pyramidal neurons, and decrease the expression of HIF-1α, IL-1β, TNF-α, and VEGF mRNAs and proteins in both brain tissue and serum (P < 0.05). Furthermore, significantly lower MDA expression and higher GSH activity were detected in the three groups treated with Shouzhangshen compared with the low-pressure hypoxia group (P < 0.05). However, no significant alteration was observed for SOD activity (P > 0.05).

Conclusion: Our findings suggest that Shouzhangshen extract may have a significant effect on acute high altitude hypoxia-induced brain injury in mice.