Dietary inclusion of royal jelly modulates gene expression and activity of oxidative stress enzymes in zebrafish

Here we investigated the effects of different levels of royal jelly in zebrafish (Danio rerio) diets [0.0% (D1); 0.1% (D2); 0.4% (D3); 1.6% (D4) vs 6.4% (D5)] on the activity and expression profiles of superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase and glutathione S-transferase. Muscle, liver and kidney tissue samples were obtained from fish fed during 8 weeks. In these tissues, enzyme activity was determined by means of spectrophotometer and gene expression by quantitative real-time PCR. mRNA levels of the enzymes were elevated in almost all diet groups compared to the control (D1). It was determined that enzyme activities were also increased in general by supplementation of royal jelly although some decreases were also observed. However, the significant correlation between gene expression and enzyme activity was not observed in all tissues. It was concluded that main regulation occurs with post-translational modifications although effects at transcriptomic level demonstrated a snap variation.

Automated summary

The study investigated the effects of different levels of royal jelly on the enzyme activity and gene expression profiles in zebrafish tissues. While mRNA levels of enzymes were generally elevated in fish fed with royal jelly, there was some decrease in enzyme activity as well. The correlation between gene expression and enzyme activity was not significant in all tissues, suggesting that post-translational modifications may play a key role in regulation.