Coix seed seedlings-derived exosome-like nanovesicles (CSSELNs) have demonstrated significant potential in alleviating ionizing radiation (IR)-induced damage. However, the role of bioactive substances, particularly whether microRNAs (miRNAs) significantly contribute to their radioprotective effects, remains unclear. In this study, we identified miRNAs enriched in CSSELNs by small RNA sequencing, followed by validation of the key miRNAs. It was found that sbi-miR5564a confers protection against IR-induced oxidative stress in THLE-2 cells. Bioinformatics analysis together with cell-based and animal experiments were conducted to explore their potential mechanism. The results indicated that sbi-miR5564a, when delivered through CSSELNs, targeted and downregulated EP300, thereby modulating the JNK/FOXO3a signaling pathway, leading to the restoration of reactive oxygen species to normal levels and protection against IR-induced damage. Notably, a single oral dose of sbi-miR5564a@CSSELNs, which were highly enriched with sbi-miR5564a, exerted highly effective protective effects in vivo, comparable to that achieved by 30-day oral gavage of CSSELNs alone. This study not only clarified the radioprotective effect of sbi-miR5564a but also established CSSELNs as a natural miRNA delivery platform. This advancement promotes the application of plant-derived nanovesicles in radioprotective effects and the development of functional foods.

Radiation technology is widely utilized in the industrial, medical, and military fields. However, high-dose radiation causes significant harm to the human body. Ionizing radiation can alter various epigenetic modifications in animal tissues, thereby influencing phenotypic outcomes, and these effects are transmitted inter- and trans-generationally, making radiation protection particularly important. The development of radioprotective agents represents a major research direction in the field of radiation protection, with natural radioprotective agents offering advantages such as prolonged efficacy and favorable safety profiles. Conventional natural radioprotective agents include polyphenols, polysaccharides, alkaloids, and saponins. In recent years, novel categories have also been identified or developed, such as food-derived exosome-like vesicles, nanotechnology-enabled formulations, and radiation-induced microorganisms. Although some natural radioprotective agents have been successfully applied in the health food industry, their broader development faces several challenges, including incompletely elucidated mechanisms of action, low screening efficiency, high production costs, low bioavailability, and insufficient stability. Future research should address these limitations through three key areas: clarifying the mechanisms underlying radioprotective effects, efficiently screening for functional ingredients, and developing effective delivery systems for active components. Integrated multi-omics approaches, such as transcriptomics, metabolomics and epigenomics, coupled with artificial intelligence are expected to elucidate the mechanisms of action of natural radioprotective agents and enhance the efficiency of screening for functional radioprotective ingredients. Furthermore, biotechnological tools including enzyme engineering, fermentation engineering and synthetic biology enable efficient production of these functional ingredients. Concurrently, natural product-derived formulations, particularly environmentally responsive delivery systems, exhibit improved bioavailability and stability. Additionally, the application scope of natural radioprotective agents across different categories of radiation protection should be expanded. By establishing efficient screening, production, and delivery systems for natural radioprotective agents, their in-depth development and broad application can be promoted.

Poria cocos is a traditional Chinese medicinal and edible fungus. Poria cocos polysaccharides possess biological activities such as antioxidant and anti-inflammatory effects, making them a novel resource for functional foods. To promote the industrial application of Poria cocos polysaccharides in functional foods, this study utilized liquid fermentation technology to prepare Poria cocos exopolysaccharides (PCE) and compared them with Poria cocos fruiting body polysaccharides (PCP) in terms of intestinal microbiota regulation and in vivo oxidative damage protection. The results showed that PCE contained (53.98 ± 0.19)% of total sugars as well as (6.64 ± 0.51)% of proteins. Two fractions (PCE-0 and PCE-0.2) were obtained by purification of PCE, which had smooth clustered and rough flaky microscopic morphology, respectively. Both of them were composed of glucose, mannose, galactose and other monosaccharides, with β-glycosidic bonds and higher branched structures. PCE-0 contained a triple helical structure while PCE-0.2 did not. In vivo results showed that PCE increased the abundance of probiotics such as Bacteroides, Oscillospira, and Akkermansia in the mouse intestine, exerting a positive influence on maintaining intestinal homeostasis. Additionally, PCE effectively enhanced the activity of superoxide dismutase and glutathione peroxidase in the serum, liver and jejunum of oxidative-damaged mice. It also reduced malondialdehyde content, improved total antioxidant capacity, and regulated the levels of IL-1β, IL-6, IL-10, TNF-α. These effects protected the mice against oxidative damage and inflammation caused by alcohol-induced liver injury. Further molecular mechanism studies suggest that PCE alleviates alcohol-induced liver injury through activation of the Keap1/Nrf2 signaling pathway. This study aimed to explore the potential application of liquid fermented Poria cocos polysaccharides in functional foods, providing a reference for the development and utilization of liquid fermentation products from edible fungi.

To explore an ideal alternative approach for radiation protection, this study quantified vitamin C (≥ 2.5%) and total flavonoids (≥ 2%) in Rosa roxbunghii Tratt. juice concentrate. Its antioxidant capacity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation, and hydroxyl radical scavenging assays, and its efficacy in radiation protection was assessed by cell and animal experiments. Results showed that R. roxbunghii Tratt. juice concentrate scavenged all three free radicals and significantly suppressed the reduction in HL-7702 cell viability caused by ionizing radiation. Compared with the radiation model group, the spleen index and superoxide dismutase (SOD) activity in the serum and spleen, the malondialdehyde (MDA) content in the serum and liver, and the glutathione content in the serum, liver and spleen of mice treated with 1.0 g/kg of R. roxbunghii Tratt. juice concentrate for 30 days were significantly alleviated, and it also had a protective effect against liver function damage caused by radiation. This study lay the basis for establishing quality grading standards for R. roxbunghii Tratt. juice concentrate and for its application to functional foods.

It is well known that exposure to environmental stresses could enhance the adaptability of bacteria and up-regulate the expression of a variety of oxidative stress-related genes and antioxidant enzymes. It is unclear whether the adaptability of microorganisms formed naturally in special environments could transfer to other organisms. The study aimed to evaluate the effects of untreated and ethanol-induced Lactococcus lactis intracellular extracts (U-IE and E-IE) on alcohol metabolism in mice. The positive effects of E-IE on alcohol metabolism in mice were revealed by the enhanced latency of loss of righting reflex (LORR), the reduced duration of LORR, the decrease of blood alcohol concentration, as well as the elevation of alcohol dehydrogenase (ADH) activities in the stomach and liver tissues. Furthermore, the potential benefits of E-IE on the liver were evaluated by biochemical parameters including the activities of serum transaminase, the levels of antioxidant enzymes, and the pathological changes of liver tissue. The present work put forward a new point that appropriate ethanol stress could enhance the intracellular ADH activity of L. lactis, and its intracellular extracts could continue to enhance alcohol metabolism in mice.

Insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) extracted from wheat bran were modified by snail enzyme and their physicochemical properties (water retention capacity and oil retention capacity), functional properties (cholesterol adsorption capacity, glucose adsorption capacity and antioxidant activity) and structural characterizations were evaluated. The results showed that snail enzyme modification led to the significant increase in oil retention capacity of IDF, glucose adsorption capacity and cholesterol adsorption capacity of IDF and SDF. Enzymatic modification also markedly improved the DPPH radical scavenging capacity and reducing power of IDF and SDF. Meanwhile, scanning electron microscopy (SEM) analysis indicated the microstructures of IDF and SDF powders were significantly changed. Fourier transfer-infrared spectrometry (FT-IR) showed that snail enzyme modification could degrade the part of cellulose and hemicellulose of IDF and SDF. All these improved physicochemical and functional properties of IDF and SDF might depend on their structural changes. It suggested that snail enzyme modification could effectively improve physicochemical and functional properties of IDF and SDF from wheat bran.