The effect of Iridoids effective fraction of Valeriana jatamansi Jones on movement function in rats after acute cord injury and the related mechanism.

Abstract

Spinal cord injury (SCI) is a disastrous central nervous system (CNS) disorder, which was intimately associated with oxidative stress. Studies have confirmed that Iridoids Effective Fraction of Valeriana jatamansi Jones (IEFV) can scavenge reactive oxygen species. This study aimed to confirm the efficacy of IEFV in ameliorating SCI. For establish the SCI model, the Sprague-Dawley rats underwent a T10 laminectomy with transient violent oppression by aneurysm clip. Then, the rats received IEFV intragastrically for 8 consecutive weeks to evaluate the protective effect of IEFV on motor function, oxidative stress, inflammation and neurotrophic factors in SCI rats. Basso, Beattie and Bresnahan scores, hematoxylin and eosin (H&E) staining and transmission electron microscopy experiments found IEFV protected motor function and alleviated neuron damage. Meanwhile, IEFV treatment decreased the release of malondialdehyde, interleukin-6 (IL-6), cyclooxygenase-2 and tumor necrosis factor-α. Moreover, IEFV treatment elevated the expression levels of brain-derived neurotrophic factor and nerve growth factor of SCI rats. Finally, administration of IEFV significantly inhibited the expression of p-p65 and toll-like receptor 4 (TLR4). This study suggests that IEFV could attenuate the oxidative stress and inflammatory response of the spinal cord after SCI, which was associated with inhibition of the TLR4/nuclear factor-kappaB signaling pathway.