The study investigates the role of heme oxygenase 1 (Hmox1) in iron homeostasis in mammals. Hmox1 is responsible for breaking down heme into biliverdin, carbon monoxide, and free iron. The researchers generated mice lacking functional Hmox1 and found that these animals developed anemia with low serum iron levels but accumulated iron in the liver and kidneys, leading to oxidative damage, tissue injury, and chronic inflammation. This indicates that Hmox1 plays a crucial role in releasing iron from hepatic and renal cells, which is essential for maintaining iron homeostasis. The findings provide insights into human iron metabolic disorders, such as hereditary hemochromatosis and anemia of chronic inflammation, and suggest that modulating Hmox1 activity could be a therapeutic approach to improve iron levels and reduce inflammation.The study investigates the role of heme oxygenase 1 (Hmox1) in iron homeostasis in mammals. Hmox1 is responsible for breaking down heme into biliverdin, carbon monoxide, and free iron. The researchers generated mice lacking functional Hmox1 and found that these animals developed anemia with low serum iron levels but accumulated iron in the liver and kidneys, leading to oxidative damage, tissue injury, and chronic inflammation. This indicates that Hmox1 plays a crucial role in releasing iron from hepatic and renal cells, which is essential for maintaining iron homeostasis. The findings provide insights into human iron metabolic disorders, such as hereditary hemochromatosis and anemia of chronic inflammation, and suggest that modulating Hmox1 activity could be a therapeutic approach to improve iron levels and reduce inflammation.