HEPH and obesity due to melanocortin 4 receptor deficiency: To investigate whether HFD induced obesity and calorie restriction affected iron absorption, mRNA levels of duodenal enzymes involved in iron transport, divalent metal transporter1 (Dmt1), ferroportin (Fpn), duodenum cytochrome 1b (Dcyt1b), and hephaestin (Heph) were measured (Fig. 5).