To investigate the heavy metal contamination of soil in a uranium mining area in northern Guangdong, a physicochemical evaluation method was used to evaluate the contaminated soil near the pit and tailings pond of the uranium mining area, determine its heavy metal content and evaluate its ecological risk using the Nemerow integrated contamination index, ground accumulation index and potential ecological risk index. The results show that the average content of nine heavy metal elements in the soil of the uranium mining area exceeds the background value of red soil in Guangdong Province. Three pollution evaluation indices all indicate that Cd, As and U have serious pollution and high ecological risk, while the remaining elements are weakly polluted and the potential ecological risk of the six sampling sites all show very strong risk. On this basis, soil ecotoxicity was evaluated using ostracods (Cypridopsis vidua and Heterocypris sp.), Vibrio fischeri and Vicia faba L. Higher concentrations of heavy metals at individual sites (T1, T2, P2) resulted in higher mortality of ostracods, higher inhibition of Vibrio fischeri luminescence and a significant reduction in germination and pigmentation of broad beans. The results of the biotoxicity evaluation were consistent with the results of the physicochemical evaluation, allowing for a more direct and comprehensive evaluation of the ecotoxic effects of uranium and heavy metals in the mine soils.

Non-alcoholic fatty liver disease (NAFLD), the most prevalent chronic liver illness, is characterized by hepatic steatosis. Exercise and probiotics can regulate the gut microbiota to treat NAFLD; however, their combined effects and the mechanisms of gut-liver communication remain unclear. Inconsistent results on probiotic efficacy further warrant investigation. In this study, zebrafish fed a high-fat diet (HFD) for six weeks were subjected to swimming exercise (HFDE), probiotic intervention (HFDP), or a combination of both (HFDEP) for 10 weeks to explore their effects on NAFLD and the corresponding mechanism. The results showed that NAFLD alleviation followed the order HFDEP > HFDE > HFDP. HFDEP and HFDE treatments effectively reduced Body Mass Index (BMI), relative liver weight, liver vacuolation density, lipid droplets in liver sections, triglyceride, free fatty acid, glucose, and pyruvic acid. In contrast, a single probiotic treatment had limited impact, suggesting a complementary role in NAFLD treatment. Glucose and fatty acid metabolism were central to the “gut–liver” axis. The reduced conversion of glucose to pyruvic acid, decreased fatty acid synthesis and esterification, and accelerated fatty acid transformation to CO₂ contributed to NAFLD improvement under HFDE and HFDEP treatments. This study provides promising theoretical groundwork for potential prevention and treatment strategies for NAFLD.