Chromium: Biological Relevance
Published Online: 15 MAR 2006
Copyright © 2006 John Wiley & Sons, Ltd
Encyclopedia of Inorganic Chemistry
How to Cite
Vincent, J. B. 2006. Chromium: Biological Relevance. Encyclopedia of Inorganic Chemistry. .
- Published Online: 15 MAR 2006
The biochemistry of CrIII has been a poorly understood field of endeavor; studies of the biochemistry of none of the other transition metals have been as problematic. Despite four decades of investigation, only recently has a clear picture of the role of Cr been defined potentially. The biologically important form is the trivalent ion, although not in the form of the purported glucose tolerance factor. Apparently, CrIII is required for proper carbohydrate and lipid metabolism in mammals, although Cr deficiency is difficult to achieve. Conditions that increase circulating glucose and insulin concentrations increase urinary chromium output. Cr is excreted after an insulin challenge, probably in the form of the oligopeptide chromodulin. Chromodulin may be the key to understanding the role of Cr at a molecular level as the molecule has been found to bind to the activated insulin receptor, stimulating its kinase activity. A mechanism for the action of chromodulin has been proposed recently. The popular nutritional supplement chromium picolinate has been associated with potentially deleterious effects. The mechanism of toxicity of chromate (CrVI) is still an area of intense investigation.
- insulin receptor;
- glucose tolerance factor;
- chromium picolinate;
- low-molecular-weight chromium-binding substance;