Editors' ChoiceAlzheimer's Disease

Herbals for Alzheimer's

Science's STKE  20 Feb 2001:
Vol. 2001, Issue 70, pp. tw4
DOI: 10.1126/stke.2001.70.tw4

Phytoestrogens, also known as flavonoids, are found in plants and herbal medicines. When applied to cortical neurons in culture, the flavone apigenin and the flavonol kaempferol decreased apoptosis induced in those cells by treatment with amyloid β protein (Aβ). Both flavonoids inhibited caspase activity stimulated by Aβ treatment and apigenin was also able to inhibit the release of cytochrome c. A second mechanism by which flavonoids may be neuroprotective is through their antioxidant properties. Many flavonoids were able to inhibit the increase in reactive oxygen species (ROS) produced by treatment with Aβ; however, their antioxidant activity did not correlate well with neuroprotective activity. The most effective neuroprotection was seen when cells were treated agents that could inhibit both the production of ROS and caspase activation, for example kaempferol alone was highly effective and the combination of quercetin (a strongly antioxidant flavonoid) or the nonflavonoid antioxidant probucol with apigenin was also highly effective.

C.-N. Wang, C.-W. Chi, Y.-L. Lin, C.-F. Chen, Y.-J. Shiao, The neuroprotective effects of phytoestrogens on amyloid β protein-induced toxicity are mediated by abrogating the activation of caspase cascade in rat cortical neurons. J. Biol. Chem. 276, 5287-5295 (2001). [Abstract] [Full Text]