Agrimonia pilosa Ledeb., Cinnamomum cassia Blume, and Lonicera japonica Thunb. protect against cognitive dysfunction and energy and glucose dysregulation by reducing neuroinflammation and hippocampal insulin resistance in β-amyloid-infused rats. (7th February 2017)

• Record Type: Journal Article
• Authors: Park, Sunmin; Kang, Suna; Kim, Da Sol; Moon, Bo Rerum
• Is Part Of: Nutritional neuroscience. Volume 20:Number 2(2017)
• Page Start: 77
• Page End: 88
• Publication Date: 2017-02-07
• Subjects: Lonicera japonica Thunb -- Agrimonia pilosa Ledeb -- Cinnamon -- Amyloid-β -- Cognitive dysfunction -- Glucose metabolism; Neuropharmacology -- Periodicals; Diet -- Periodicals; Diet therapy -- Periodicals; Nutrition -- Periodicals; 615.78
• DOI: 10.1080/1028415X.2015.1135572
• Languages: English
• ISSNs: 1028-415X

Abstract

Abstract : Objectives : The water extracts of Cinnamomum cassia Blume bark (CCB; Lauraceae), Lonicera japonica Thunb . flower (LJT; Caprifoliaceae), and Agrimonia pilosa Ledeb . leaves (APL; Rosaceae) prevented amyloid- β (25–35)-induced cell death in PC12 cells in our preliminary study. We evaluated whether long-term oral consumption of CCB, LJT, and APL improves cognitive dysfunction and glucose homeostasis in rats with experimentally induced AD-type dementia. Methods : Male rats received hippocampal CA1 infusions of amyloid- β (25–35, AD) or amyloid- β (35–25, non-plaque forming, normal-controls, Non-AD-CON), at a rate of 3.6 nmol/day for 14 days. AD rats were divided into four groups receiving either 2% lyophilized water extracts of CCB, LJT, or APL or 2% dextrin (AD-CON) in high-fat diets (43% energy as fat). Results : Hippocampal amyloid- β deposition, tau phosphorylation, and expressions of tumor necrosis factor (TNF)-α and inducible nitric oxide synthase (iNOS) (neruoinflammation markers) were increased, and insulin signaling decreased in AD-CON. CCB, LJT, and APL all prevented hippocampal amyloid- β accumulation and enhanced hippocampal insulin signaling. CCB, LJT, and APL decreased TNF-α and iNOS in the hippocampus and especially APL exhibited the greatest decrease. AD-CON exhibited cognitive dysfunction in passive avoidance and water maze tests, whereas CCB, LJT, and APL protected against cognitive dysfunction, and APL was most effective and was similar to Non-AD-CON. AD-CON had less fat oxidation as an energy fuel, but it was reversed by CCB, LJT, and especially APL. APL-treated rats had less visceral fat than AD-CON rats. AD-CON rats exhibited impaired insulin sensitivity and increased insulin secretion during oral glucose tolerance test compared with Non-AD-CON, but CCB and APL prevented the impairment. Discussion : These results supported that APL, LJT, and CCB effectively prevent the cognitive dysfunction and the impairment of energy and glucose homeostasis induced by amyloid- β deposition by reducing neuroinflammation and enhancing insulin signaling. APL exhibited the greatest effectiveness for improving cognitive function.