Conformational epitope alterations in ready-to-eat sea cucumber reduce allergenic responses and confer neuroprotective benefits in aging mice

Abstract

With advancing age, the human immune system gradually declines, increasing susceptibility to allergic reactions to protein-rich foods such as sea cucumbers. Consequently, identifying appropriate processing methods to reduce their allergenicity has become an urgent research priority. This study systematically evaluated the potential effects of sea cucumbers processed by desalination (DSC), boiling (BSC), and rehydration after boiling (RSC) on sensitization and improvement of memory impairment by constructing a D-galactose-induced aging mouse model. The results revealed that mice in the DSC group displayed the most pronounced allergic response, accompanied by a significant increase in serum levels of specific IgE and IgG₁. In contrast, the allergic symptoms of the RSC group mice were significantly alleviated, and the degranulation of mast cells was effectively inhibited. Additionally, this treatment approach helped regulate the dynamic balance of Th1/Th2 immune responses and reduce histopathological damage. Modification of epitopes affects the structural properties of allergens, thereby diminishing or abolishing the immune system's identification and binding of these allergens, ultimately mitigating the incidence of allergic reactions. The prediction of allergenic sites indicated that RSC significantly altered the linear epitope structure of sea cucumber allergens, resulting in five epitopes becoming undetectable, one being entirely cleaved, and two being partially cleaved. Meanwhile, the learning and memory abilities of mice in the RSC group were also significantly enhanced. In conclusion, the functional characteristics and allergenicity of sea cucumbers are largely influenced by processing methods. RSC not only effectively reduces the allergenic risk of sea cucumbers in aging individuals but also has the potential to improve cognitive dysfunction.

Keywords

Sea cucumber / Rehydration after boiling / Older population / Allergy / Neuroprotection / Conformational epitope

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