Neuroprotective Role Of Tocotrienoland On Spinal Cord Injury In Rats And Its Mechanism

Objective: To evaluated the effect of tocotrienols on spinal cord injury via oxidative stress,inflammation and inducible nitric oxide synthase(iNOS)in rats,in order to explore the neuroprotective effect of tocotrienols on spinal cord injury and its mechanism.Methods: In model of spinal cord injury(SCI)rats was induced by operation.SCI rats were treated with 120 mg/kg/day tocotrienols once a day for 8 consecutive weeks.Functional recovery after SCI was measured by Basso Beattie Bresnahan(BBB).Then we tested the volume of spinal cord contusions after SCI in rats.In SCI rats,serum malondialdehyde(MDA),superoxide dismutase(SOD),CAT,glutathione peroxidase(GSH-PX),tumor necrosis factor(TNF-α),NF-κB p65 unit,IL-1β/6 levels were analyzed by the respective commercial immunoassay kits.Firstly,iNOS,TGF-β,collagen type IV and fibronectin protein expressions,iNOS activity and plasma NO production in SCI rats was analyzed by western blot analysis,commercial kits and Griess reagent,respectively.Results: Those changes happened after treatment on SCI with tocotrienol: 1)BBB score was significantly increased in rat spinal cord contusion and edema significantly reduced(P<0.05).2)Serum oxidative stress indicators including SOD,CAT,GSH-PX and inflammatory markers NF-κBp65,TNF-α,IL-1β,IL-6,and iNOS activity and NO levels were significantly decreased,while the level of MDA significantly increased compared with SCI group(P<0.05).3)The expression of iNOS,TGF-β,type IV collagen and fibronectin in spinal cord tissue also reduced significantly(P<0.05).Conlusion: 1)Tocotrienol can improve the neurological function of spinal cord injury.2)Tocotrienols protected against SCI with reduced oxidative stress and inflammation,and inhibited iNOS protein expression iNOS activity and plasma NO production in rats.3)Tocotrienols suppressed TGF-β,collagen type IV and fibronectin protein expressions in SCI rats.Those results indicate that tocotrienols protect SCI,and suppress oxidative stress,inflammation and iNOS in this model of SCI through TGF-β,collagen type IV and fibronectin signaling pathway,thus playing a role in neuroprotection.