Persicaria minor ameliorates the cognitive function of chronic cerebral hypoperfusion rats: Metabolomic analysis and potential mechanisms

Persicaria minor (P. minor) is a herbal plant with many uses in food, perfume, and the medical industry. P. minor extract contains flavonoids with antioxidant and anticholinesterase capacity, which could enhance cognitive functions. P. minor extract has been proven to enhance memory. However, its role in an animal model of chronic cerebral hypoperfusion (CCH), which resembles human vascular dementia, has yet to be explored. Therefore, the present study investigates the effects of chronic (14 days) administration of aqueous P. minor extract on different stages of learning and memory processes and the metabolic pathways involved in the chronic cerebral hypoperfused rats induced by the permanent bilateral occlusion of common carotid arteries (PBOCCA) surgery. Chronic treatment of P. minor extract at doses of 200 and 300 mg/kg, enhanced recognition memory of the PBOCCA rats. P. minor extract (200 mg/kg) was also found to restore the spatial memory impairment induced by CCH. A high dose (300 mg/kg) of the P. minor extract significantly increased the expression of both ACh and GABA neurotransmitters in the hippocampus. Further, distinctive metabolite profiles were observed in rats with different treatments. Three major pathways involved in the cognitive enhancement mechanism of P. minor were identified. The present findings demonstrated an improving effect of P. minor extract on memory in the CCH rat model, suggesting that P. minor extract could be a potential treatment for vascular dementia and Alzheimer's patients. P. minor is believed to improve cognitive deficits by regulating pathways involved in retinol, histidine, pentose, glucuronate, and CoA metabolism.