Serum iron, percentage saturation and ferritin are increased. A serum ferritin test checks iron levels and can point to further treatment. Ferritin levels help assess if iron deficiency is contributing to the anemia. A low serum ferritin is most commonly found. Monitoring serum ferritin may also be useful, aiming to decrease ferritin levels to . Vegetarianism is not a cause of low serum ferritin levels, despite the common myth. Activated macrophages secrete ferritin and plasminogen activator leading to hyperfibrinolysis. The level of serum ferritin that is viewed as "high" depends on the condition. Levels of the iron-binding protein ferritin may be extremely elevated with this disorder. Mitochondrial ferritin has many roles pertaining to molecular function. Defects in ferritin proteins are associated with several neurodegenerative diseases. The function and structure of the expressed ferritin protein varies in different cell types. Inside the ferritin shell, iron ions form crystallites together with phosphate and hydroxide ions. A human mitochondrial ferritin, MtF, was found to express as a pro-protein. Hemosiderin is also generated from the abnormal metabolic pathway of ferritin.