Manganese gluconate

Manganese is an essential trace element that is naturally present in many foods and available as a dietary supplement. Manganese is a cofactor for many enzymes, including manganese superoxide dismutase, arginase, and pyruvate carboxylase [1,2]. Through the action of these enzymes, manganese is involved in amino acid, cholesterol, glucose, and carbohydrate metabolism; reactive oxygen species scavenging; bone formation; reproduction; and immune response [3-7]. Manganese also plays a role in blood clotting and hemostasis in conjunction with vitamin K [5]. Manganese is absorbed in the small intestine through an active transport system and, possibly, through diffusion when intakes are high [2]. After absorption, some manganese remains free, but most is bound to transferrin, albumin, and plasma alpha-2-macroglobulin. Manganese is taken up by the liver and other tissues, but the mechanism of this process is not well understood [1,2]. The human body contains about 10 to 20 mg manganese, of which 25% to 40% is in bone [1,2]. The liver, pancreas, kidney, and brain also contain manganese. The body maintains stable tissue manganese concentrations through regulatory control of manganese absorption and excretion [5]. More than 90% of absorbed manganese is excreted via bile into the feces, and a small amount is reabsorbed [1,2,4,5]. Very little is excreted in urine.