Apart from antioxidant activities, natural products have exhibited other vital properties to combat AD progression through anti-inflammatory response, prevention of Aβ aggregation, accumulation of tau protein, and the promotion of cholinergic signaling
[178][97]. Alkaloids, such as cryptolepine and tetrandrine, have been reported to be involved in the inhibition of NF-κB, thereby acting as anti-inflammatory agents
[179][98]. Flavonoids, owing to their characteristic property of inhibiting inflammatory response, have shown potential for working against AD progression
[180][99]. Studies in animal models of AD have reported terpenoids, such as artemisinin, parthenolide, and carnosol can inhibit NF-κB and p38 MAPK pathways
[181,182,183][100][101][102]. Ginsenoside Rg1, a compound obtained from the roots of the Ginseng plant, has been reported to cause a significant drop in levels of Aβ peptide levels in AD mice
[184][103]. Natural plant products like crocin, α-cyperone, chrysophanol, and aloe-emodin have been found to exhibit properties that inhibit tau protein formation and reduce AD progression
[185,186,187][104][105][106]. Caffeine, one of the most widely consumed alkaloids, has been found to inhibit Aβ deposition in vitro
[188][107]. It was also found to reduce ROS production and enhance SOD levels in human neuroblastoma cells cultured with Aβ
[189][108]. Caffeine has also been shown to exhibit anti-neuroinflammatory properties as well as decreasing tau protein phosphorylation in the hippocampus
[190][109]. In low to moderate doses, caffeine inhibits AChE, thereby improving cognitive actions and reducing the progression of AD
[191][110]. Eugenol, found in cloves, has been reported to reduce amyloid plagues and increase memory in rat models induced with Aβ peptides
[192][111]. Dietary patterns have also been found to impact the onset and progression of AD. A Western diet characterized by higher meat intake was associated with an increased risk of AD
[193][112]. In contrast to this, the Mediterranean diet, characterized by higher consumption of fruits, vegetables, and fish with lower meat intake, was found to reduce the risk of AD in the population
[194][113].