Low-molecular-weight chromium-binding substance and biomimetic [Cr_3O(O_2CCH_2CH_3)_6(H_2O)_3]~+ do not cleave DNA under physiologically-relevant conditions

摘要

Chromium(III) tris(picolinate), Cr(pic)_3, is currently a very popular nutritional supplement; however, at physiologically-relevant concentrations, it has recently been demonstrated to cleave DNA [J. K. Speetjens, R. A. Collins, J. B. Vincent, S. A. Woski, Chem, Res. Toxicol. 12 (1999) 483]. A number of other chromium-containing compounds have been proposed as substitutes for Cr(pic)_3. Of particular interest are low-molecular-weight chromium-binding substance (LMWCr) and [Cr_3O(O_2CCH_2CH_3)_6(H_2O)_3]~+ 1. The former compound has recently been identified as the biologically active form of chromium in mammals, activating the kinase activity of insulin receptor in the presence of insulin. Complex 1 is a functional biomimetic for LMWCr. Both compounds have been proposed as possible nutritional supplements and therapeutics for adult-onset diabetes. This work demonstrates that these complexes, unlike Cr(pic)_3, are poor DNA-cleaving agents and may represent safer materials for human consumption.