Ocimum sanctum extract preserves neuronal echotexture and controls seizure in lithium-pilocarpine induced status epilepticus rats

Objective:To investigate the effect of Ocimum sanctum hydroalcoholic extract(OSHE)on seizure control and neuronal injury in rats with lithium-pilocarpine-induced status epilepticus(SE). Methods:SE was induced by administering lithium chloride followed by pilocarpine 24 h later.OSHE was administered either alone or in combination with valproate(VPA)3 days before SE induction until 14 days post-SE induction.Seizure parameters were recorded on day 1(0-3 h),day 1-3 and day 4-14 post-SE.On day 14 post-SE,neurobehavioural tests(elevated plus maze and passive avoidance)were done followed by total antioxidant capacity,neuron-specific enolase,immunohistochemistry,and electron microscopic assessment in the hippocampus and cortex tissue. Results:OSHE+VPA provided more significant seizure protection(75%)than VPA(62.5%),OSHE(62.5%),or SE control(12.5%)(overall P=0.003).The latency to stage-3/4 seizures was increased and the number of stage-3/4 seizures was reduced in all treatment groups compared to the SE control group(P=0.002 and<0.001,respectively).The OSHE+VPA group also had better memory retention than other treatment groups(P<0.001)in the passive avoidance test.Total antioxidant capacity level was significantly higher and neuron-specific enolase was lower in the OSHE and OSHE+VPA groups compared to the SE control group.Electron microscopic study showed significant myelin sheath damage(67.5%,P<0.05)and axonal degeneration(51.8%,P<0.001)in the hippocampus of the SE control group,which were alleviated by OSHE or OSHE+VPA treatment.In immunohistochemical analysis,the OSHE,OSHE+VPA,and VPA groups had a significantly higher number of viable neurons and less neuronal loss compared to the SE control in the hippocampus(P<0.001). Conclusions:OSHE either alone or in combination with VPA shows better seizure control by preservation of neuronal echotexture and reducing oxidative stress in the hippocampus.