Background: There is a close association of neuroinflammation with the pathogenesis of AD and involves the activation of glial cells in neurodegenerative diseases such as AD suggest that STZ treatment caused enhanced neuroinflammatory mediators and altered redox stress that contribute to the neurodegenerative processes.

Aim: To evaluate the neuroprotective effect of Croton hirtus against streptozotocininduced alzhemier’s disease in rats.

Materials and Methods: A total of 30 rats were divided into 5 groups 6 rats in each. Group I considered as normal control. Group II served as negative control. Group III, IV and V were treated with Donepezil (3 mg/kg), ethanolic extract of Croton hirtus200mg/kg and 400 mg/kg respectively for 14 consecutive days followed by single administration of streptozotocin (60 mg/kg) to all the groups except group I. Cognitive performance was assessed by the Morris water maze, elevated plus maze and passive avoidance paradigm. Acetyl cholinesterase enzyme level, biochemical markers such as lipid peroxidation, reduced glutathione and β amyloid 1 42 level, histopathological study of rat brain were estimated.

Results:Croton hirtusand Donepezil rats showed significant increase in escape latency in Morris water maze. Additionally, Croton hirtusextract remarkably promoted the cholinergic neurotransmission, decreasing β amyloid protein and protected against the oxidative stress damage as indicated by, increasing reduced glutathione level. Furthermore, histopathological studies revealed the reversal of neuronal damage in the treatment group compared to streptozotocin treated rats.

Conclusion: Croton hirtu sextract showed promising neuroprotective activity against streptozotocininducedalzhemier’s disease in rats. This could be attributed to its brain acetyl cholinesterase level, β amyloid level inhibition, antioxidant activity.

Keywords: Croton hirtus, Neuroprotective, Acetylcholinesterase, β amyloid protein,Streptozotocin