Multiomics Perspective to Analyze the Mechanism by Which Dietary Sugar Aggravates Tropomyosin-Induced Allergic Reactions: The Key Role of Intestinal Microbiota Imbalance and Metabolic Disorders

High sugar intake is associated with an increased allergic disease risk, though the mechanisms are unclear. This study used a tropomyosin-sensitized mouse model to compare the effects of sucrose, fructose, glucose, and mixed sugars. All sugars exacerbated allergic reactions, with sucrose having the most pronounced effect, characterized by elevated histamine levels and upregulated expression of pro-inflammatory factors. Sucrose intake significantly downregulated expression of zonula occludens-1 and occludin, and increased intestinal permeability. Further analysis demonstrated that sucrose intake enriched pro-inflammatory bacteria, resulting in intestinal microecology imbalance. Nontargeted metabolomics identification showed that sucrose intake caused significant changes in 238 metabolites, with over 70% exhibiting a downward trend. Tryptophan metabolism was notably suppressed, and the key metabolites like tryptophol and kynurenic acid were down-regulated. Additionally, arginine and proline metabolism were also inhibited. These findings provide new understanding of the mechanisms by which high sugar consumption exacerbates allergic diseases.