There will be generated some adverse conditions in the process of acquculture farming with the continuous improvement of the intensive degree of modern aquaculture, such as crowding stress, hypoxia, and malnutrition, which will easily lead to oxidative stress. Se is an effective antioxidant, participating and playing an important role in the antioxidant defense system of fish. This paper reviews the physiological functions of selenoproteins in resisting oxidative stress in aquatic animals, the mechanisms of different forms of Se in anti-oxidative stress in aquatic animals and the harmful effects of lower and higher levels of Se in aquaculture. To summarize the application and research progress of Se in oxidative stress in aquatic animals and provide scientific references for its application in anti-oxidative stress in aquaculture.

With the advancement of radiological medicine and nuclear industry technology, radiation is increasingly used to diagnose human health disorders. However, large-scale nuclear leakage has heightened concerns about the impact on human organs and tissues. Selenium is an essential trace element that functions in the body mainly in the form of selenoproteins. Selenium and selenoproteins can protect against radiation by stimulating antioxidant actions, DNA repair functions, and immune enhancement. While studies on reducing radiation through antioxidants have been conducted for many years, the underlying mechanisms of selenium and selenoproteins as significant antioxidants in radiation damage mitigation remain incompletely understood. Therefore, this paper aims to provide new insights into developing safe and effective radiation protection agents by summarizing the anti-radiation mechanism of selenium and selenoproteins.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is one of the most prevalent chronic diseases in the world, lacking specific pharmacological interventions or well-established treatments. MASLD involves intricate pathological mechanisms characterized by oxidative stress and robust inflammatory responses. Selenium, an essential trace element, plays a critical role in antioxidation, regulation of inflammation, anticancer activity, and so on. Recent studies have reported that supplementation with selenium could alleviate MASLD and associated hepatic disorders, while excessive consumption may result in insulin resistance or even selenosis. Therefore, supranutritional selenium supplementation can be more suitable for the therapy and prevention of MASLD. This paper comprehensively reviews research about selenium and MASLD to highlight the potential applications and risks of supranutritional selenium supplementation in MASLD, following three steps: conducting a search, reviewing research articles and reviews, and discussing results. The keywords for the search include but are not limited to selenium, MASLD, supranutritional, hepatic diseases, selenoproteions, and selenium nanoparticles (SeNPs). We have reached the following conclusions: supranutritional selenium supplementation exhibits promising potential as a strategy to treat MASLD, but there are still some risks, depending on the dose and form of selenium; evaluating MASLD severity and selenium nutritional status accurately, as well as supplementing with superior forms of selenium (e.g., organic selenium and SeNPs), can further ensure the safety and efficacy of selenium supplementation. However, relationships between selenium homeostasis disorders and the occurrence and development of MASLD have not been fully elucidated. Methods for comprehensively assessing selenium status and mechanisms of selenosis require further investigation and research.

Sea urchins, ecologically important marine species, host a complex gut microbiota that plays a significant role in their digestion, nutrient acquisition, and overall health. The gut microbes, along with endogenous enzymes, facilitate the breakdown of macroalgae and other food sources. Environmental factors, including temperature, salinity, and habitat type, can greatly influence the microbial communities within sea urchins. Dietary variations can also lead to shifts in the abundance and composition of intestinal bacteria, highlighting the strong connection between diet and gut microbiota. The sea urchin’s unique anatomy and digestive system adaptations contribute to their ability to process and absorb nutrients efficiently, supporting their varied diets. Gut microbes not only participate in the decomposition of complex carbohydrates, but also in detoxifying compounds and mitigating the impacts of inhospitable environments. Further research is needed to fully understand the intricate relationships between sea urchin species, their habitats, diets, and gut microbiota composition. A deeper understanding of these interactions may inform sustainable management and aquaculture strategies, ensure the long‐term viability of economically valuable sea urchin species, and provide insights into their ecological roles and adaptability to changing environments.

With the rapid development of the laying hen industry and the continuous innovation of farming technology, egg production continues to increase. Eggs are rich in proteins, lipids, and immunoglobulins (IgY) found in the egg yolk. IgY can be used to treat human diseases and prevent bacterial and viral infections. In addition, IgY has advantages over IgG in biological structure and function and is characterized by high specificity, safety, yield, and economic efficiency. This review describes the basic structure and properties of IgY, lists a variety of IgY purification methods, and outlines measures to maintain and enhance its activity, focusing on the current status of its research in immunoprevention and treatment of human diseases and outlines its importance, and finally proposes the current challenges and future research priorities of IgY in the field of biomedical research to provide a scientific basis for the wide range of applications of IgY in human health.