Plant-Derived Antioxidants Protect the Nervous System From Aging by Inhibiting Oxidative Stress

Abstract

Alzheimer's disease (AD) has become a major disease contributing to human death and is thought to be closely related to the aging process. The rich antioxidant substances in plants have been shown to play a role in delaying aging, and in recent years, significant research has focused on also examining their potential role in AD onset and progression. Many plant-derived antioxidant research studies have provided insights for the future treatment and prevention of AD. This article reviews various types of plant-derived antioxidants with anti-aging effects on neurons. Also it distinguishes the different types of active substances that exhibit different degrees of protection for the nervous system and summarizes the mechanism thereof. Plant-derived antioxidants with neuroprotective functions can protect various components of the nervous system in a variety of ways and can have a positive impact on interventions to prevent and alleviate AD. Furthermore, when considering neuroprotective agents, glial cells also contribute to the defense of the nervous system and should not be ignored.

Keywords: nerve aging; nerve cells; nervous system; neuroprotection; plant-derived antioxidants.

FIGURE 1

Protective method of plant-derived active substances on nerves. Active plant substances exhibit rich neuroprotective methods, which can be grouped into seven categories: (1) promote the activation of glial cells, (2) promote cell proliferation, (3) regulation of Ca²⁺, (4) maintain nerve cell structure, (5) provide resistance to oxidative stress, (6) reduce inflammation, and (7) anti-Alzheimer’s protein. The active substances falling into each of these seven categories are provide in the respective boxes. All the active substances could resist oxidative stress, and some substances have similar protection patterns.

FIGURE 2

Neuronal protection by the immune nervous system. Schematic of an immune-functioning nervous system that is protecting neurons through the combined action of astrocytes and microglia. Astrocytes tightly combine with the blood vessels of the brain to form a blood–brain barrier to filter out harmful substances and allow beneficial nutrients to enter the brain. Moreover, astrocytes can secrete glutathione precursors to strengthen the oxidative defense of neurons. Microglia in this example are depicted as exhibiting the M2 phenotype with immune function rather than the M1 phenotype that can trigger neuroinflammation. M2 microglia can recognize and break down Aβ and inflammatory factors and reduce damage to neurons.