Neuroprotective herbs and foods from different traditional medicines and diets

Abstract

Plant secondary metabolites include an array of bioactive constituents form both medicinal and food plants able to improve human health. The exposure to these phytochemicals, including phenylpropanoids, isoprenoids and alkaloids, through correct dietary habits, may promote health benefits, protecting against the chronic degenerative disorders mainly seen in Western industrialized countries, such as cancer, cardiovascular and neurodegenerative diseases. In this review, we briefly deal with some plant foods and herbs of traditional medicines and diets, focusing on their neuroprotective active components. Because oxidative stress and neuroinflammation resulting from neuroglial activation, at the level of neurons, microglial cells and astrocytes, are key factors in the etiopathogenesis of both neurodegenerative and neurological diseases, emphasis will be placed on the antioxidant and anti-inflammatory activity exerted by specific molecules present in food plants or in remedies prescribed by herbal medicines.

Figure 1

Ginkgo biloba L. tree (a) and its typical fan-shaped leaves (b).

Figure 2

Main flavonoids (quercetin, kaempferol and isorhamnetin), ginkgolides (A, B, C, J, M) and bilobalide of Ginkgo biloba L.

Figure 3

Panax ginseng C.A. Meyer: aerial parts (a) and root (b).

Figure 4

Ginsenosides of Panax ginseng C.A. Meyer root; Rb1 and Rg1 are characterized by different aglycones, protopanaxadiol and propanaxatriol, respectively.

Figure 5

Scutellaria baicalensis Georgi aerial parts.

Figure 6

Main flavonoids isolated from Scutellaria baicalensis Georgi root.

Figure 7

Curcuma longa L.: aerial parts (a) and rhizome (b).

Figure 8

Curcuminoids, polyphenolic constituents of turmeric, the dried ground rhizome of Curcuma longa L.

Figure 9

Traditional Mediterranean cultivations: Olea europea L. (a) and Vitis vinifera L. (b).

Figure 10

A stilbene (resveratrol) and a flavonoid (catechin) typically present in grape products.

Figure 11

Salvia officinalis L.: flowers (a) and leaves (b).

Figure 12

Main isoprenoids (mono- and sesquiterpenes) present in essential oil extracted from aerial parts of Salvia officinalis L.

Figure 13

Coffea arabica L.: leaves and fruits (coffee cherries).

Figure 14

Caffeine and structurally related methylxanthines found primarily in tea (theophylline) and chocolate (theobromine); paraxanthine is the main hepatic metabolite of caffeine after coffee ingestion.

Figure 15

Camellia sinensis Kuntze: leaves and flowers.

Figure 16

Chemical structures of major catechins.