Effects of Blighia Sapida Seed Powder on Gene Expression of Juvenile Catfish Clarias Gariepinus (Burchell 1822).

Abstract

The study investigates the effects of Blighia sapida (ackee) seed powder on the health and gene expression of juvenile African catfish, Clarias gariepinus. It aims to assess the toxicity of Blighia sapida (ackee) seeds which contains toxic bioactive compounds, notably hypoglycin A and hypoglycin B, which are known to disrupt metabolic processes in vertebrates. However, information on their molecular effects in aquatic organisms is limited. Juvenile C. gariepinus were exposed to varying concentrations (0.0, 30.0, 31.6, 33.3, 35.0, 36.6 mg/L) of the seed powder for 96 hours. The exposure of juvenile C. gariepinus to Blighia sapida seed powder induces significant stress behaviours such as erratic swimming, loss of reflex, air-gulping, and barbel deformation, which worsened with increasing concentrations. After exposure, Liver tissues were harvested for RNA extraction, cDNA synthesis, and quantitative real-time polymerase chain reaction (RT-qPCR) analysis of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β). Results revealed significant upregulation of TNF-α and IL-1β gene expression in treated groups compared to the control, indicating dose-dependent inflammatory and stress responses. This aligns with previous findings that Blighia sapida phytochemicals can influence gene regulation, immunity, and metabolism which may compromise fish health and productivity in aquaculture systems. Hence, Blighia sapida seed should be avoided in close proximity to fish ponds and aquaculture environments.