Metals in Biological Systems

The purpose of this book is to give the reader integral information of the importance of chemical elements in biology systems, showing the recent advances obtained by modern biochemical and molecular biology technologies. The participation of particular elements, such as iron, cesium, cadmium, arsenic, calcium, zinc, selenium, aluminum, and copper in the biological systems is analyzed in each chapter. Calcium, iron, zinc, copper and selenium are indispensable for the mammalian health, while the other elements are harmful for biological systems. Even the elements that are indispensable for the normal metabolism can be associated to disease, sometimes being incompatible with life when present in concentrations below or above the normal values. Cadmium preferentially accumulates in the kidney, the major target for cadmium-related toxicity. The generation of reactive oxygen species (ROS) has been considered crucial mediators for cadmium tissue injuries. Tap water may be an important source of exposure to arsenic. Oxidative stress has been one of the prime factors in arsenic-induced carcinogenicity. On the other hand, a prolonged exposure to aluminum may impact also health. Occupational exposure to aluminum is allied with a reduced level of serum prolactin, and may lead to significant loss of pituitary cells. In the radioecological context, radioactive isotopes of cesium are some of the most hazardous radionuclides, which for example, were released into the biosphere following the Chernobyl accident. The uptake of radionuclides by plant roots constitutes the main pathway for the migration of radiocesium from soil to humans, via food chain. The authors hope that the lector finds in this book actualized information that can help him to prepare the class for his university student in courses of bioinorganic subject and can begin new research.