RESUMEN
Objective: To investigate the effect of naringein on the cognition of rats with Alzheimer's diseases (AD), its regulation on amyloid β-protein (Aβ) and Tau antibody, and its potential mechanism of improving the cognition of rats with AD. Methods: AD model of rats was established by intracerebroventricular (icv) Streptozotocin (STZ) on days 1 and 3, and then naringein and Rosiglitazone were ig administered. Rats in model and control groups were treated with the same volume of physiologic saline to induce dementia model. On day 21 after the first operation, spatial learning and memory of rats were tested in Morris water maze. The expression of insulin-degrading enzyme (IDE), glycogen synthase kinese-3β (GSK-3β), phospho-GSK-3β (pGSK-3β), Tau, and phospho-Tau (pTau) were measured by Western blotting. Aβ42 and Aβ40 levels in the brain of the AD rats were tested by immunohistochemistry. Results: Cognition of AD rats administered with naringein and Rosiglitazone could be recovered by Morris water maze (P < 0.05). Western blotting results showed that both naringein and Rosiglitazone could improve the expression of IDE and decrease the activity of GSK-3β, and reduce the phosphorylation level of Tau (P < 0.05). Immunohistochemistry demonstrated that the Aβ42 and Aβ40 in cerebral cortex of rats treated by naringein and Rosiglitazone were both decreased. Conclusion: Naringein as a peroxisome proliferator-activated receptor γ (PPARγ) excitomotor could act as insulin sensitizer, and could alleviate the cognition of AD rats, Aβ deposition, and phosphorylation of Tau through regulating the expression of insuline-related IDE and GSK-3β.
RESUMEN
Objective To determine the appropriate collecting -time of Exocarpium citri grandis,the chemical compo-sition in Exocarpium citri grandis in different fruit -ages was compare d and analyzed.Methods Contents of naringein and bergapten were compared by TLC an d the total dihydroflavones in Exocarpium citri grandis was determined by spec-trophotometmic analysis with detection wavelength at 384nm.Results With the increase of fruit -age,the c ontents of naringein and total dihydroflavones in Exocarpium citri grandis decreased and the content of bergapt en increased.Con-clusion Fruit -age has an obviously effect on the chemical composition in Exocarpium citri grandis and collecting -time can influence the quality of medicin e materials.Further studies of Exocarpium citri grandis should be combined pharma-codynamics for fixing collecting -t ime.