Abstract
Background: Food allergy (FA) is associated with dietary habits, antibiotic use, living environment, and delivery method. Pregnancy and lactation represent critical periods for neonatal immune system development. Methods: This study investigated the relationship between maternal dietary habits and FA risk in offspring. Pregnant C57BL/6J mice (8-week-old males and females) were fed either a high-fat diet (HFD) or HFD supplemented with fermented apple juice (FAJ) during pregnancy and lactation. Offspring were nursed by their respective dams until weaning at 21 days postpartum, followed by ovalbumin (OVA) sensitization. Lipid profiles, acylcarnitines, immunological, and histopathological analyses were performed. Gut microbiota composition and serum markers were also assessed. Results: The findings indicated that maternal HFD had a negative impact on OVA-sensitized offspring mice. Early-life FAJ intervention modulated gut microbiota alterations and alleviated maternal HFD-worsened allergic symptoms through Th1/Th2 and Th17/Treg immunity balance and intestinal barrier repair. Maternal serum triglyceride and total cholesterol levels, along with gut microbiota profiles, significantly influenced offspring gut microbiota composition. Moreover, reduced short-chain and medium-chain acylcarnitines in offspring may be associated with increased allergy risk. Conclusions: Maternal HFD during pregnancy and lactation disrupted gut microbiota balance and exacerbated offspring FA susceptibility. These findings provide a scientific foundation for developing early-life FA prevention strategies.