Trivalent chromium (CrIII) as a trace element essential for animals and humans

Abstract

Trivalent chromium is considered an essential element in the nutrition of both animals and humans. Animal studies confirm many beneficial effects of organic and inorganic chromium compounds on carbohydrate, protein and lipid metabolism in the body. Glucose tolerance factor (GTF) has been demonstrated to involve an active form of trivalent chromium, which sustains normal glucose metabolism. Cr(III) compounds form enzymes and ribonucleic acids, accelerate blood clotting and increase β-glucuronidase activity. Chromium also participates in antioxidant processes, in the synthesis of RNA and DNA and in the immune response, as well as affects secretion of hormones and some vitamins. It has been demonstrated that chromium improves lean body mass in animals, increases growth rate and feed conversion and improves feed intake and energy efficiency. Organic chromium reduces mortality and improves animal reproduction parameters. It also enhances immunity and strengthens response to preventive vaccination. It has been noted in many animal species that a diet low in chromium leads to deficiency symptoms, such as reduced feed intake, lower weight gains, reproductive disorders and increased lipid levels. Chromium deficiency can also result from stress. Moderate chromium deficiency is a risk factor of ischemic heart disease with myocardial infarction. Such a condition may pose a great risk of coronary artery disease. Dietary chromium requirement of an animal body is probably 300 μg Cr/kg d.w. of feed, which is usually satisfied by the ration provided. The highest concentration of chromium is found in the hair, skin and teeth, followed by the liver, kidneys, spleen, and slightly lower in the heart, muscles, pancreas, lungs, bones and brain. Chromium absorption rates in the human intestine range between 0.5 and 2% of the daily intake of inorganic Cr forms, and from 25 to 30% of the element ingested as organic complexes. Clinical studies show that the kinetics of chromium excretion from the system are complex and can be described by a multi-range model, the half-life ranging from 13 min to 192 days. Dietary chromium nanocomposite supplementation (CrNano) used in pigs nutrition has significantly increased Cr content in the blood, longissimus muscle, heart, liver, kidneys, jejunum and ileum. Chromium nanocomposite supplementation acts more effectively on the tissues and, as a consequence, increases the accumulation of the element. .