Carcinogenic Chromium(VI) Compounds Formed by Intracellular Oxidation of Chromium(III) Dietary Supplements by Adipocytes. Issue 5 (22nd December 2015)

• Record Type: Journal Article
• Authors: Wu, Lindsay E.; Levina, Aviva; Harris, Hugh H.; Cai, Zhonghou; Lai, Barry; Vogt, Stefan; James, David E.; Lay, Peter A.
• Is Part Of: Angewandte Chemie international edition. Volume 55:Issue 5(2016)
• Page Start: 1742
• Page End: 1745
• Publication Date: 2015-12-22
• Subjects: adipocytes -- cancer -- chromium -- oxidation -- X-ray fluorescence microscopy; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201509065
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Chromium(III) nutritional supplements are widely consumed for their purported antidiabetic activities. X‐ray fluorescence microscopy (XFM) and X‐ray absorption near‐edge structure (XANES) studies have now shown that non‐toxic doses of [Cr3 O(OCOEt)6 (OH2 )3 ] + (A ), a prospective antidiabetic drug that undergoes similar H2 O2 induced oxidation reactions in the blood as other Cr supplements, was also oxidized to carcinogenic Cr VI and Cr V in living cells. Single adipocytes treated withA had approximately 1 μm large Cr hotspots containing Cr III, Cr V, and Cr VI (primarily Cr VI thiolates) species. These results strongly support the hypothesis that the antidiabetic activity of Cr III and the carcinogenicity of Cr VI compounds arise from similar mechanisms involving highly reactive Cr VI and Cr V intermediates, and highlight concerns over the safety of Cr III nutritional supplements. Abstract : Dangerous oxidation : Synchrotron‐based single‐cell mapping and XANES spectroscopic techniques revealed the formation of chromium hotspots containing mixtures of Cr III, Cr V, and Cr V species in cultured mouse adipocytes that had been treated with Cr III dietary supplements. These findings provide evidence for the hypothesis that the consumption of such supplements may pose a cancer risk.