Preface

Iron is a vital trace element for humans, as it plays a crucial role in oxygen transport, oxidative metabolism, cellular proliferation, and many catalytic reactions. To be beneficial, the amount of iron in the human body needs to be maintained within the ideal range. Iron metabolism is one of the most complex processes involving many organs and tissues, the interaction of which is critical for iron homeostasis. The bone marrow is the prime iron consumer in the body, being the site for erythropoiesis, while the reticuloendothelial system is responsible for iron recycling through erythrocyte phagocytosis. Among the numerous proteins involved in iron metabolism, hepcidin is a liver-derived peptide hormone, which is the master regulator of iron metabolism. This hormone acts in many target tissues and regulates systemic iron levels through a negative feedback mechanism. Hepcidin synthesis is controlled by several factors such as iron levels, anemia, infection, inflammation, and erythropoietic activity. In addition to systemic control, iron balance mechanisms also exist at the cellular level and include the interaction between iron-regulatory proteins and iron-responsive elements. Genetic and acquired diseases of the tissues involved in iron metabolism cause a dysregulation of the iron cycle. Consequently, iron deficiency or excess can result, both of which have detrimental effects on the organism.

This book contains eight chapters divided into three sections on iron, iron metabolism and iron deficiency and new lines of therapy.

Nowadays, research is increasingly dedicated to the field of iron metabolism, but countless questions remain unanswered. Increased knowledge of the physiology of iron homeostasis facilitates understanding the pathology of iron disorders, such as iron deficiency and iron overload, and leads to improved outcomes.

#### **Marwa Zakaria**

Associate Professor of Pediatrics, Faculty of Medicine, Pediatric Department, Zagazig University, Zagazig, Egypt

#### **Tamer Hassan**

Professor of Pediatrics, Faculty of Medicine, Pediatric Department, Zagazig University, Zagazig, Egypt

Section 1
