Cornus mas ameliorates AlCl3-induced Alzheimer's disease in rats with metabolic syndrome by regulating inflammation and oxidative stress.

Objectives: Alzheimer's disease (AD) results from different risk variables, such as metabolic syndrome (MetS) and environmental factors. The benefits of Cornus mas L. on diabetes are well-known. However, the impacts of C. mas fruits on AD or MetS-related cognitive dysfunction have not yet been studied. We evaluated the impact of C. mas fruit (80% ethanol) extract in an animal model of MetS and AD.

Methods: Male Spraque-Dawley rats were administered a high-fat, high-sugar diet for 105 days alone or with an AlCl₃ intraperitoneal injection for the last 60 days. C. mas fruit extract (400, 700, and 1000 mg/kg peroral) was administered for 60 days. After conducting behavioral tests and measuring blood pressure, hippocampal tissues and serum samples were obtained. The phytochemical analyses were conducted on C. mas fruit extract.

Results: C. mas alleviated MetS by reducing blood glucose, total cholesterol, and systolic blood pressure levels. Behavioral tests demonstrated that C. mas improves AlCl₃-related cognitive decline in rats with MetS, which was supported by the neuroprotective effect of C. mas in histological analysis. C. mas dose-dependently reduced amyloid-β, malondialdehyde levels, acetylcholinesterase activity in the hippocampus, proinflammatory cytokines in serum, and elevated glutathione levels in the hippocampus. Phytochemical analyses revealed that C. mas fruit contains loganic acid, cornuside, and anthocyanins.

Discussion: C. mas fruit extract in every three doses given could improve cognitive decline due to MetS and AlCl₃ through alleviation of MetS, oxidative stress and inflammation, prevention of amyloid deposition, and increased cholinergic transmission.