Free radicals, such as reactive oxygen species (ROS), are well recognized for playing a dual role as both deleterious and beneficial species. Normally, ROS formation is tightly regulated by enzymes, and low/moderate concentrations of ROS are involved in physiological function, such as cellular signaling systems and defense against infectious agents. However, overproduction of ROS results in oxidative stress, which can cause oxidization of lipid, protein and DNA, eventually resulting in cell damage or death. In order to defend against oxidative stress, organisms develop an antioxidant defense system. The system consists of enzymatic antioxidants (e.g. superoxide dismutase, glutathione peroxidase and catalase), non-enzymatic antioxidants (e.g. glutathione, vitamin C, carotenoids and flavonoids) and key signaling pathways (e.g. Nrf2 pathway). Under normal conditions, there is a balance between the free radicals formation and antioxidants level, which is essential for the health of organisms.
In intensive aquaculture, farmed animals are inevitably stimulated by a variety of stress factors, leading to stress responses. Oxidative stress is the most important form of stress response. Under oxidative stress, excessive ROS will attack cellular macromolecules, such as protein, DNA and lipid, causing damage to cells and tissues. In aquaculture environment, many factors, such as high stocking density, inappropriate temperature, heavy metals exposure, and bacteria and viruses infection, can induce oxidative stress. Strong oxidative stress can inhibit growth and development, reduce immunity, and induce tissues damage and disease outbreak in aquatic animals. Thus, oxidative stress is regarded as a key cause of pathologies that affect the health and production in aquatic animals. Over the past decades, numerous studies have focused on the effects of oxidative stress on the health and production in aquatic animals, but several questions remain to be elucidated, such as key molecular mechanisms and pathways involved in oxidative stress, composition of antioxidant defense system in crustaceans and strategies for coping with oxidative stress in aquaculture.
In this Research Topic, we aim to discuss the relationship among free radicals, oxidative stress and antioxidants in aquatic animal health and disease, such as key pathways involved in oxidative stress, the molecular mechanisms of oxidative stress-induced tissue damage and novel defense mechanisms against oxidative stress. The topics of interest include but are not limited to the following:
• The effect of environmental factors (e.g. temperature, salinity and dissolved oxygen) on redox state;
• Mechanisms involved in toxicant-induced oxidative damage;
• The effect of oxidative stress on growth, physiological function and tissue damage;
• key molecular mechanisms and pathways involved in oxidative stress;
• Novel defense mechanisms against oxidative stress;
• Exogenous antioxidant additives screening and evaluation in defense against oxidative stress
Free radicals, such as reactive oxygen species (ROS), are well recognized for playing a dual role as both deleterious and beneficial species. Normally, ROS formation is tightly regulated by enzymes, and low/moderate concentrations of ROS are involved in physiological function, such as cellular signaling systems and defense against infectious agents. However, overproduction of ROS results in oxidative stress, which can cause oxidization of lipid, protein and DNA, eventually resulting in cell damage or death. In order to defend against oxidative stress, organisms develop an antioxidant defense system. The system consists of enzymatic antioxidants (e.g. superoxide dismutase, glutathione peroxidase and catalase), non-enzymatic antioxidants (e.g. glutathione, vitamin C, carotenoids and flavonoids) and key signaling pathways (e.g. Nrf2 pathway). Under normal conditions, there is a balance between the free radicals formation and antioxidants level, which is essential for the health of organisms.
In intensive aquaculture, farmed animals are inevitably stimulated by a variety of stress factors, leading to stress responses. Oxidative stress is the most important form of stress response. Under oxidative stress, excessive ROS will attack cellular macromolecules, such as protein, DNA and lipid, causing damage to cells and tissues. In aquaculture environment, many factors, such as high stocking density, inappropriate temperature, heavy metals exposure, and bacteria and viruses infection, can induce oxidative stress. Strong oxidative stress can inhibit growth and development, reduce immunity, and induce tissues damage and disease outbreak in aquatic animals. Thus, oxidative stress is regarded as a key cause of pathologies that affect the health and production in aquatic animals. Over the past decades, numerous studies have focused on the effects of oxidative stress on the health and production in aquatic animals, but several questions remain to be elucidated, such as key molecular mechanisms and pathways involved in oxidative stress, composition of antioxidant defense system in crustaceans and strategies for coping with oxidative stress in aquaculture.
In this Research Topic, we aim to discuss the relationship among free radicals, oxidative stress and antioxidants in aquatic animal health and disease, such as key pathways involved in oxidative stress, the molecular mechanisms of oxidative stress-induced tissue damage and novel defense mechanisms against oxidative stress. The topics of interest include but are not limited to the following:
• The effect of environmental factors (e.g. temperature, salinity and dissolved oxygen) on redox state;
• Mechanisms involved in toxicant-induced oxidative damage;
• The effect of oxidative stress on growth, physiological function and tissue damage;
• key molecular mechanisms and pathways involved in oxidative stress;
• Novel defense mechanisms against oxidative stress;
• Exogenous antioxidant additives screening and evaluation in defense against oxidative stress
