BDH2 and nutritional disorder: BDH2 plays a crucial role in intracellular homoeostasis of iron and regulates the immune function of macrophages.42,43 Siderophore transports ferrous iron to mitochondria, since its absence leads to iron deficiency in mitochondria, and as a result, to an increase in the level of iron in cells.10 Mitochondria are the main place of iron utilisation.