Astragaloside improves outcomes of traumatic brain injury in rats by reducing microglia activation.

Astragaloside (AST) is traditionally prescribed for the prevention and treatment of cerebrovascular diseases. We directly tested the therapeutic effects of AST in a rat model of traumatic brain injury (TBI). One hour after the onset of TBI rats were given Saline (1 ml/kg) or AST (20-80 mg/kg) via i.p. injection. AST causes the attenuation of TBI-induced cerebral contusion, neuronal apoptosis, and neurological motor dysfunction. TBI-induced microglial activation evidenced by the morphological transformation of microglia (or ameboid microglia) and the microglial overexpression of tumor necrosis factor-alpha was reduced by AST. Our results indicate that AST may protect against brain contusion and neuronal apoptosis after TBI by attenuating microglia activation in male rats.