Effect of Chromium Picolinate and Chromium Nanoparticles Added to Low- or High-Fat Diets on Chromium Biodistribution and the Blood Level of Selected Minerals in Rats

The metabolism of chromium (Cr), calcium (Ca), phosphorus (P), iron (Fe), copper (Cu), and zinc (Zn) is interconnected, and their deficiency or excessive accumulation may lead to various disturbances, including anemia and diabetes. The current research was undertaken to determine whether low-fat or high-fat diets with the Cr(III) addition in the form of picolinate (CrPic) or nanoparticles (CrNPs) have an interactive effect on the retention and accumulation of this element in organs and the content of P, Ca, Fe, Cu and Zn in the blood plasma of rats. The experiment was performed using 48 outbred male Wistar rats fed a low-fat or high-fat semi-purified rat diet with dietary addition of chromium at a dose of 0.3 mg/kg body weight. The obtained results point to the paramount importance of the dietary Cr form on the excretion pattern of this microelement. It has been found that CrNPs were to a greater extent excreted from the rat’s body via urine and feces in comparison to CrPic, as indicated by the values of the Cr retention index (44.4 vs . 65.9%, respectively). The additional dietary Cr, irrespective of its form and diet type, was not accumulated in the analyzed internal organs, i.e. brain, spleen, kidneys, liver, thigh bone, and thigh muscle. It should be stressed that dietary CrPic, unlike CrNPs, added to the high-fat diet adversely reduced plasma concentration of vital minerals in comparison to the levels observed in rats fed the low-fat diet, i.e. Zn (60.5 vs. 69.9 µM), Cu (13.6 vs. 15.7 µM), and P (1.12 vs. 1.30 µM). In turn, the CrNPs, but not CrPic, added to the high-fat diet decreased plasma Fe level (1.41 vs. 2.43 µM).