The bioinorganic chemistry of chromium(III)

The biochemistry of chromium(III) has been a poorly understood field of end eavor. Despite four decades of investigation, only recently has a somewhat clear picture of the role of Cr been refined. Chromium(III) is required for proper carbohydrate and lipid metabolism in mammals, although chromium def iciency is difficult to achieve. Conditions that increase circulating gluco se and insulin concentrations increase urinary chromium output. Chromium is excreted after an insulin challenge in the form of the oligopeptide chromo dulin. Chromodulin may be the key to understanding the role of chromium at a molecular level as the molecule has been found to bind to activated insul in receptor, stimulating its kinase activity. An examination of the history of studies of chromium picolinate and glucose tolerance factor illustrates the difficulties and problems associated with biochemical studies dealing with chromium(III). (C) 2001 Elsevier Science B.V. All rights reserved.