Evaluation of In Vivo Anti Alzheimer's Activity of Vigna radiata and Vigna pilosa using Beta Amyloid Induced Neurotoxicity in Rats

Abstract

AD is the most common form of dementia. Extracellular senile (amyloid) plaques and intracellular neurofibrillary tangles (NFTs) are hallmarks of the disease. Vigna radiata and Vigna pilosa are plants used in many Ayurvedic formulations used in the management of dementia and related conditions. The present study was aimed to evaluate the neuroprotective effect of these plants on an amyloid-β (Aβ) 1-42 model of Alzheimer’s disease in rats. Duration of the study was 21 days. After the recovery period post Aβ1-42 ICV administration, from the 8thday, the ethyl acetate extract of Vigna radiata and ethanolic extract of Vigna pilosa (200mg/kg, 400mg/kg), Donepezil (3mg/kg) treatments were made once daily p.o till the 21st day. Cognitive behavioural studies were conducted using radial maze test, Step-through Passive Avoidance Test. The animals were further subjected to euthanasia and the brain were collected and evaluated for antioxidant parameters and brain cytokine levels. The brain tissues were subjected to histopathological examination. The treatment with the extracts significantly improved the cognitive capability of the rats in the Radial arm maze task and step through passive avoidance test. It also reduced oxidative stress, which was evident by the lower levels of lipid peroxide and nitric oxide as well as elevated levels of antioxidant enzymes like catalase, superoxide dismutase and reduced glutathione. The treatment alleviated neuroinflammation in rats by decreasing the concentration of neuroinflammatory markers in a dose-dependent manner. From the results it can be concluded that the plants Vigna radiata and Vigna pilosa has beneficial effects in the improvement of cognitive impairment AD, by reducing oxidative stress and neuroinflammation. Key Words: Alzheimer’s disease, Vigna radiata, Vigna pilosa, amyloid-β.