Table 2.

Promising preclinical studies of flavonoids and their neuroprotective role against Alzheimer’s disease.

Flavonoids	Models	Concentrations	Effects	References
Quercetin	3xTg-AD mice model	100 mg/kg	Reduces Aβ protein, tauopathy in hippocampus and amygdala	[106]
Naringin	Intracerebroventricular (ICV) streptozotocin (STZ) induced-cognitive impairment in rat	50, 100 and 200 mg/kg	Improves mitochondrial dysfunction-induced oxido-nitrosative stress as well as inflammatory surge	[107]
Naringenin	ICV STZ-induced dementia model of rats	25, 50 mg, 100 mg/kg	Reduces brain Aβ levels and reversed tau hyper-phosphorylation through downregulation of glycogen synthase kinase-3β (GSK-3β) activity in hippocampus and cerebral cortex	[108]
Nanoparticle of epigallocatechin-3-gallate	APPswe/PS1dE9 mice	-	Increase in synapses, and reduction in neuroinflammation as well as Aβ plaque burden	[109]
Epicatechin	PC12 cells treated with Aβ25–35	10 µM	Reduces Aβ-induced neurotoxicity	[110]
Catechin	PC12 cells treated with Aβ25–35	10 µM	Reduces Aβ-induced neurotoxicity	[110]
Luteolin	STZ-induced AD rat	10 and 20 mg/kg	Improves spatial learning and memory impairment	[111]
Diosmin	3xTg-AD mice	1 and 10 mg/kg/day	Enhances inhibitory GSK-3β phosphorylation and lessen γ-secretase activity, Aβ generation, as well as tau hyperphosphorylation	[112]
Wogonin	3xTg-AD mice	10  mg/kg	Attenuates amyloidogenic pathway and increased mitochondrial membrane potential and protected against apoptosis	[113]