Macrophages in oxidative stress and models to evaluate the antioxidant function of dietary natural compounds

Abstract

Antioxidant testing of natural products has attracted increasing interest in recent years, mainly due to the fact that an antioxidant-rich diet might provide health benefits. Activated macrophages are a major source of reactive oxygen species, reactive nitrogen species, and peroxynitrite generated through the so-called respiratory burst. Constitutively released proinflammatory cytokine, especially tumor necrosis factor-α, triggers nuclear factor-κB, and activator protein-1 translocation leading to the over production of reactive oxygen species and reactive nitrogen species in macrophages. Activation of transcription factors in the long-lived tissue-resident macrophages and/or monocyte-derived macrophages, trigger epigenetic modifications leading to the pathogenesis of chronic diseases. Nutraceuticals including lipid raft structure disruption agent, cholesterol depletion agent, farnesyltransferase inhibitor, nuclear factor-κB blocker (α,β-unsaturated carbonyl compounds), glucocorticoid receptor agonist, and peroxisome proliferator-activated receptor-γ agonist have long been used to inactive macrophage. The inhibition effects on the formation of nitric oxide, superoxide, and nitrite peroxide may be responsible for the anti-inflammatory functionalities. Activated macrophage models could be used to identify the active components for functional diets development through a multiple targets strategy.

Idebenone Protects against Acute Murine Colitis via Antioxidant and Anti-Inflammatory Mechanisms

“…The significant reduction of pro-inflammatory cytokine levels by idebenone could be either a direct immunomodulatory effect or indirectly reflective of a general protection of antioxidant enzymes and/or barrier integrity. Since macrophages seem to play a vital role in colitis through the production of many cytokines [81,90], detailed studies will be required to elucidate the effect of idebenone on macrophages and to identify the functional links between ROS and cytokine levels.…”

Phytochemical analysis and biological activities of in vitro cultured Nidularium procerum, a bromeliad vulnerable to extinction

“…Reactive oxygen species, such as hydrogen peroxide (H 2 O 2 ) and superoxide anion (O 2 − ), are generated in the first minutes of macrophage stimulation, during the so-called "respiratory burst" 69 . They are involved in the inflammation process, acting as efficient protectors; however, uncontrolled or excessive ROS production can further promote oxidative stress -a disruption in the redox balance system that contributes to damaging the body´s own cells and tissues 70 .…”

Lactobacillus paracasei ssp. paracasei YBJ01 reduced d-galactose–induced oxidation in male Kuming mice

“…Under normal physiological condition, free radicals and reactive oxygen species (ROS), including superoxide anions (O 2 − ), hydrogen peroxide (H 2 O 2 ), hydroxyl radicals ( • OH), and peroxynitrite (ONOO − ) are generated from aerobic metabolism (Bonomini et al, 2015); however, an imbalance between endogenous antioxidants and accumulation of ROS causes oxidative stress. Chronic oxidative stress could induce degenerative disorders such as carcinogenesis, rheumatoid arthritis, atherosclerosis, neurodegenerative diseases, and Alzheimer's disease in humans (Chen et al, 2010;Callaway and Jiang, 2015;Castaneda et al, 2017). Normally, excess ROS are scavenged by endogenous antioxidants such as superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase, and nonenzyme glutathione, coenzyme Q10, and uric acid and perturbations in these systems may case ROS accumulation and oxidative stress (Chen et al, 2015).…”