Utilization of molecular oxygen by aerobic organisms inevitably results in the formation of a number of oxygen-containing reactive species that are collectively known as reactive oxygen species (ROS). ROS play important roles in both physiology and pathophysiology of aerobic life. The field of ‘ROS biology and medicine’ deals with the involvement of ROS and related species in contemporary biology and medicine. The purpose of this article is to survey common terms and concepts in ROS biology and medicine. It also introduces the ‘ROS paradigm’ so as to provide a conceptual framework for understanding the rapidly evolving field of ROS biology and medicine.

Literature review. Spinal cord injury (SCI) remains a major public health issue in developed countries as well as worldwide. The pathophysiology of SCI is characterized by an initial primary injury followed by secondary deterioration. Although the etiology and pathogenesis of SCI remain to be fully understood, it has been suggested that reactive oxygen species (ROS) and oxidative stress have a significant role in the pathophysiology of SCI. Thus, alleviating oxidative stress may be an effective strategy for therapeutic intervention of SCI. The aim of this review was to describe (i) the sources of ROS as well as the major antioxidant defenses with particular attention being paid to lipid peroxidation; (ii) the biomarkers of oxidative stress in SCI and (iii) the neuroprotective effects of various compounds with antioxidative properties in animal models of SCI. PubMed, one of the most comprehensive biomedical databases, was searched from 1976–2011. All relevant papers were read by title, abstract and full-length article. Oxidative stress is considered a hallmark of injury of SCI. Thus, alleviating oxidative stress may be an effective way of therapeutic intervention of SCI. Two of these agents, the glucocorticoid steroid methylprednisolone and the non-glucocorticoid 21-aminosteroid tirilazad, have been shown to possess significant antioxidant activities and improve recovery of SCI patients in clinical trials. Other promising botanical compounds and their molecular targets and mechanisms of action with regard to potential protection against SCI were also described. These include carotenoids and phenolic compounds. ROS and oxidative stress have a significant role in the pathophysiology of SCI. Alleviating oxidative stress is be an effective strategy for therapeutic intervention of SCI. Extensive research over the past several decades has identified numerous bioactive compounds that have antioxidative stress benefits in animal models of SCI. Thus, continued studies on bioactive compounds with ROS-scavenging capacity may lead to the development of effective antioxidant-based modalities for treating SCI in human subjects.

Microplastics and nanoplastics (M-NPLs) are ubiquitous environmentally, chemically, or mechanically degraded plastic particles. Humans are exposed to M-NPLs of various sizes and types through inhalation of contaminated air, ingestion of contaminated water and food, and other routes. It is estimated that Americans ingest tens of thousands to millions of M-NPLs particles yearly, depending on socioeconomic status, age, and gender. M-NPLs have spurred interest in toxicology because of their abundance, ubiquitous nature, and ability to penetrate bodily and cellular barriers, producing toxicological effects in cells, tissues, organs, and organ systems. The present review paper highlights: (1) The current knowledge in understanding the detrimental effects of M-NPLs in mouse models and human cell lines, (2) cellular organelle localization of M-NPLs, and the underlying uptake mechanisms focusing on endocytosis, (3) the possible pathways involved in M-NPLs toxicity, particularly reactive oxygen species, nuclear factor-erythroid factor 2-related factor 2 (NRF2), Wnt/β-Catenin, Nuclear Factor Kappa B (NF-kB)-regulated inflammation, apoptosis, and autophagy signaling. We also highlight the potential role of M-NPLs in increasing the incubation time, spread, and transport of the COVID-19 virus. Finally, we discuss the future prospects in this field.

For years, the consumption of a diet rich in fruits and vegetables has been considered healthy, increasing longevity, and decreasing morbidities. With the assistance of basic research investigating the potential mechanisms, it has become clear that the beneficial effects of plant-based foods are mainly due to the large amount of bioactive phenolic compounds contained. Indeed, substantial dietary intervention studies in humans have supported that the supplementation of polyphenols have various health-promoting effects, especially in the elderly population. In vitro examinations on the anti-aging mechanisms of polyphenols have been widely performed, using different types of natural and synthetic phenolic compounds. The aim of this review is to critically evaluate the experimental evidence demonstrating the beneficial effects of polyphenols on aging-related diseases. We highlight the potential anti-aging mechanisms of polyphenols, including antioxidant signaling, preventing cellular senescence, targeting microRNA, influencing NO bioavailability, and promoting mitochondrial function. While the trends on utilizing polyphenols in preventing aging-related disorders are getting growing attention, we suggest the exploration of the beneficial effects of the combination of multiple polyphenols or polyphenol-rich foods, as this would be more physiologically relevant to daily life.

Doxorubicin (also called Adriamycin) is effective in treating a wide range of human cancers and currently considered as one of the most important drugs in cancer chemotherapeutics. The clinical use of doxorubicin is, however, associated with dosage-dependent cardiotoxicity and development of heart failure, which diminish the therapeutic index of this widely used anticancer drug. This article first surveys key research findings on doxorubicin redox biology that may impact its cardiotoxicity as well as anticancer activity. It then discusses emerging concepts, especially the topoisomerase IIb‒p53‒mitochondrion axis that may lead to the development of mechanistically based novel strategies to protect against cardiotoxicity and enhance the effectiveness of doxorubicin therapy.