Azadirachta indica A. Juss flower extract attenuates memory deficit induced by restraint stress in malerats

Chronic stress is related to cognitive impairment. Azadirachta indica A. Juss. (A. indica) leaf extract possesses antioxidant and cognitive enhancement effects. Therefore, this study was set up to evaluate the cognitive-enhancing effects of A. indica flower extract in stressed rats.

Male Wistar rats were randomly divided into control and stress groups. Restraint stress was induced to stress groups 3 h daily. The stressed rats were given vehicles, donepezil (a positive control meditation used to improve cognition), and A. indica at 250, 500, and 1000 mg/kg BW for 30 days. The novel object recognition test (NORT) was used to assess cognitive function, and the open field test (OFT) was utilized to assess spontaneous locomotor activity. Their brains and blood were taken to measure levels of brain-derived neurotrophic factor (BDNF), blood cortisol levels, and the density of survival neurons.

The discrimination index ratio of the stressed rats treated with either donepezil or A. indica flower extract at all doses was significantly improved as measured by NORT. Moreover, there was no significant difference between the control and stress groups in the locomotor behaviors of rearing and number of crossing. The stressed rats treated with donepezil and A. indica flower extract had significantly higher BDNF levels and also survival neuron density in the brain. However, their blood cortisol levels were lower than the stressed rats given the vehicle.

A. indica flower extract helps improve cognitive function in stressed rats by boosting BDNF and protecting against neuronal loss in the brain.