Abstract:

Objective　To investigate the protective effects of tetrahydroxy stilbene glucoside (TSG) on ischemia-reperfusion (I/R)-induced hippocampal injury and the underlying mechanisms in gerbils.　Methods Gerbil global I/R model was established by clamping bilateral carotid arteries for 30 min followed by reperfusion for 5 days. Animals were divided into 6 groups randomly: Sham, I/R, I/R+TSG high, middle, low (6, 3, 1.5 mg/kg) and edaravone injection group (3 mg/kg). The functions of learning and memory were detected by Morris water maze 5 days after reperfusion. The number and structure of neurons and neuronal apoptosis in hippocampal CA1 region were evaluated by Nissl and TUNEL staining, respectively. In addition, the expression of active-caspase-3 in cerebral tissues was measured by Western blot.　Results　Compared to Sham group, learning and memory capacity of gerbils in I/R group declined significantly, the number of functional neurons in hippocampal CA1 region decreased dramatically. Furthermore, the apoptotic neurons indicated by TUNEL staining as well as caspase-3 activation increased remarkably. TSG administration at middle and high dose (3, 6 mg/kg) and edaravone injection significantly reversed aforementioned changes induced by I/R. In contrast, TSG administration at low dose (1.5 mg/kg) had no effect.　Conclusion　TSG had therapeutic effects on I/R induced cerebral injury, especially on delayed neuron apoptosis in hippocampal CA1 region, which may be related to its suppression effect on caspase-3 activation.

Key words: Ischemia-reperfusion, Tetrahydroxy stilbene glucoside, Hippocampal neuron, Apoptosis