Fig. 10.

Hypothesis for the influence of dietary intake of selenoneine on MeHg accumulation and toxicity. The main dietary source of selenoneine is fish, and it can be biologically synthesized from other selenium sources. Selenoneine plays an important role in selenium redox mechanisms. During MeHg exposure, selenoneine mediates the uptake of MeHg into endosomal and/or lysosomal secretion vesicles through OCTN1 function. MeHg exposure induces oxidative stress owing to the depletion of selenoneine and production of ROS. Stress-activated signaling mechanisms enhance proapoptotic ceramide signals, accelerating MeHg excretion. Demethylation occurs in the secretory lysosomal vesicles