Oral administration of dopamine boosts anti-Vibrio immunity in shrimp through Dorsal pathway activation

Dopamine is a key neurotransmitter regulating diverse physiological processes, and has been increasingly recognized as an important player in immune responses. In this study, we investigated whether dietary administration of dopamine could enhance immune defense and confer protection against vibriosis in Pacific white shrimp Penaeus vannamei. Shrimp fed with dopamine exhibited significantly upregulated expression of diverse immune effector genes, including antimicrobial peptides, C-type lectins, polyphenoloxidases, and lysozymes. Dopamine treatment also enhanced hemocyte phagocytic activity against Vibrio parahaemolyticus and increased locomotor activity. Mechanistically, dopamine activated the Dorsal signaling pathway, as evidenced by elevated Dorsal phosphorylation and nuclear translocation in hemocytes. Consequently, dopamine-fed shrimp showed significantly reduced mortality and lower bacterial loads upon V. parahaemolyticus challenge. These findings demonstrate that dietary dopamine administration enhances both humoral and cellular immunity in shrimp through Dorsal pathway activation, leading to improved resistance against vibriosis. This study provides a foundation for developing dopamine-based immunostimulatory strategies for disease management in shrimp aquaculture.