Synergistic Action of Membrane-Bound and Water-Soluble Antioxidants in Neuroprotection

Abstract

Prevention of neurodegeneration during aging, and support of optimal brain function throughout the lifespan, requires protection of membrane structure and function. We review the synergistic action of different classes of dietary micronutrients, as well as further synergistic contributions from exercise and stress reduction, in supporting membrane structure and function. We address membrane-associated inflammation involving reactive oxygen species (ROS) that produce immune regulators from polyunsaturated fatty acids (PUFAs) of membrane phospholipids. The potential of dietary micronutrients to maintain membrane fluidity and prevent chronic inflammation is examined with a focus on synergistically acting membrane-soluble components (zeaxanthin, lutein, vitamin E, and omega-3 PUFAs) and water-soluble components (vitamin C and various phenolics). These different classes of micronutrients apparently operate in a series of intertwined oxidation-reduction cycles to protect membrane function and prevent chronic inflammation. At this time, it appears that combinations of a balanced diet with regular moderate exercise and stress-reduction practices are particularly beneficial. Effective whole-food-based diets include the Mediterranean and the MIND diet (Mediterranean-DASH Intervention for Neurodegenerative Delay diet, where DASH stands for Dietary Approaches to Stop Hypertension).

Growth and Nutritional Quality of Lemnaceae Viewed Comparatively in an Ecological and Evolutionary Context

“…The essential dietary carotenoid zeaxanthin is not only needed to fight radiation damage and system-wide inflammation in humans but also to support mental acuity in healthy young adults (Figure 2; [21,22]). Zeaxanthin enhances basic membrane function in the brain, which supports mental acuity and detoxifies free radicals and other oxidants, which lessens radiation damage and the system-wide inflammation linked to less-than-optimal function, disorders, and diseases.…”

“…Zeaxanthin enhances basic membrane function in the brain, which supports mental acuity and detoxifies free radicals and other oxidants, which lessens radiation damage and the system-wide inflammation linked to less-than-optimal function, disorders, and diseases. Additional essential micronutrients act synergistically with zeaxanthin in fighting radiation damage and inflammation; zeaxanthin thus works best in a total package-provided by whole foods-with additional plant antioxidants that recycle zeaxanthin for a longer lifetime in inflammation fighting (Figure 2; [22]). Figure 2 places antioxidants with overlapping essential functions in plants and humans into the cycle of oxygen and carbon dioxide exchange, organic nutrients (e.g., protein and antioxidants), and inorganic nutrients (human waste) between photosynthetic and non-photosynthetic organisms.…”

“…Thereby, Figure 2 highlights that duckweed is an excellent plant component for a regenerative life support system on, e.g., a spacecraft (see also [23,24]). [22]). Figure 2 places antioxidants with overlapping essential functions in plants and humans into the cycle of oxygen and carbon dioxide exchange, organic nutrients (e.g., protein and antioxidants), and inorganic nutrients (human waste) between photosynthetic and non-photosynthetic organisms.…”

“…This downregulation of photosynthesis was thus associated with lower nutritional quality of the plant (Figures 8 and 9) in the form of a lower content of protein, zeaxanthin, lutein, and β-carotene (provitamin A). Lutein [70] and β-carotene [71] have additional roles in plant photoprotection and also act synergistically with zeaxanthin as membrane-soluble antioxidants that fight inflammation in humans [20][21][22]. Figures 8 and 9 illustrate responses of Lemna duckweed to a combination of high light and elevated CO 2 with respect to a suite of similar features related to plant productivity, photosynthesis, and nutritional quality for the consumer.…”

“…This downregulation of photosynthesis was thus associated with lower nutritional quality of the plant (Figures 8 and 9) in the form of a lower content of protein, zeaxanthin, lutein, and β-carotene (provitamin A). Lutein [70] and β-carotene [71] have additional roles in plant photoprotection and also act synergistically with zeaxanthin as membrane-soluble antioxidants that fight inflammation in humans [20][21][22].…”