Insulin chromium

Chromium. Chromium Ill) polentiales the action of insulin and may be considered a col actor for insulin. Chromium is thought to form a complex with insulin and insulin receptors. 

In humans and animals, chromium(III) is an essential nutrient that plays a role in glucose, fat, and protein metabolism by potentiating action of insulin. Chromium picolinate, a trivalent form of chromium complexed with picolinic acid, is used as a dietary supplement, because it is claimed to speed metabolism... 

Chromium is a trivalent cption that occurs as A typical daily intake isO-5 3-8 jimoJ (25-200 ig/day). After absorption from the diet, chromium occurs bound to transferrin. A safe and adequate intake of 50 to 200 ffg Cr/day has been established. Chromium appears to participate in glucose metabolism. The ion may play a part in mediating the hormonal effects of insulin. Chromium deficiency results in abnormally high glucose tolerance curves and impaired clearance of plasma glucose. Chromium deficiency can be induced in animals. There is evidence that... 

The question whether Cr(III) might be toxic is complicated by the fact that it is considered an essential metal. Biologically active Cr(III) facilitates the action of insulin. Chromium deficiency results in impaired glucose tolerance, which can be corrected by the administration of chromium (Anderson et al. 1983 Anderson 1986). Hypoglycemia and its associated symptoms can also be corrected by administration of chromium (Anderson et al. 1987). These effects of chromium supplementation are often associated with improvements in lipid levels, with a net decrease in total lipids and cholesterol and an increase in the ratio of HDL cholesterol to LDL cholesterol (Riales and Albrink 1981 Mossop 1983 Evans 1989 Wang et al. 1989). 

Chromium is not common even in a balanced diet and thus supplements may be of value. It may benefit newly diagnosed diabetics who have mild glucose intolerance. It may also benefit those with low blood sugar levels since it promotes the action of insulin. Chromium is best absorbed in the form of its nicotinate or picolinate salts. 

Metabolic Functions. Chromium (ITT) potentiates the action of insulin and may be considered a cofactor for insulin (137,138). In in vitro tests of epididymal fat tissue of chromium-deficient rats, Cr(III) increases the uptake of glucose only in the presence of insulin (137). The interaction of Cr(III) and insulin also is demonstrated by experimental results indicating an effect of Cr(III) in translocation of sugars into ceUs at the first step of sugar metaboHsm. Chromium is thought to form a complex with insulin and insulin receptors (136). 

There appears to be a chromium pool in individuals who are not chromium deficient (136). When there is an increase in level of cHculating insulin in response to a glucose load, an increase in circulating chromium occurs over a period of 0.5—2 h. This is foUowed by a decline and excretion of chromium in urine increases. Chromium deficiency is indicated when no increase or a small increase in blood chromium level or urine chromium occurs. 

Brewers and bakers dried yeasts are used as dietary supplements. They contribute some protein and trace minerals, and some B vitamins, but no vitamin C, vitamin B 2 or fat-soluble vitamins. The glucose tolerance factor (GTE) of yeast, chromium nicotinate, mediates the effect of insulin. It seems to be important for older persons who caimot synthesize GTE from inorganic dietary chromium. The ceU wall fraction of bakers yeast reduces cholesterol levels in rats fed a hypercholesteremic diet. 

It appears that chromium(III) is an essential trace element in mammalian metabolism and, together with insulin, is responsible for the clearance of glucose from the blood-stream. Tungsten too has been found to have a role in some enzymes converting CO2 into formic acid but, from the point of view of biological activity, the focus of interest in this group is unquestionably on molybdenum. 

Chromium is a trace mineral that is necessary to process carbohydrates and fats, as well as to help cells respond properly to insulin—an especially important function for people with diabetes. Chromium, in its safest form, can be found in whole grains, seafood, green beans, peanut butter, and potatoes. As a dietary supplement, chromium is available in several forms, including chromium picolinate, chromium chloride, chromium nicotinate, and high-chromium yeast. 

Chromium (Cr) Associated with insulin Food supply Kidney damage, lung cancer (inhalation) 50 to 200 pg (Cr3-)... 

Chromium was recognized as an essential trace element in 1955.1190 Rats fed a chromium-deficient diet developed an impaired tolerance for intravenous glucose, which could be reversed by an insulin-potentiating factor present in brewer s yeast, meat and various other foods. The insulin-potentiating factor was found to be a complex of chromium(IH)1191 and such substances have been termed Glucose Tolerance Factor(s) (GTFs). Chromium was demonstrated to be essential for humans in 1975.1192 There are several reviews of the chemistry of chromium(III) and its relationship to glucose tolerance.1193-1196... 

Glucose tolerance factor chromium in 888 Glucose transporters 415, 416 GLUT1, topology diagram 416 GLUT4, response to insulin 416 Glucosidase... 

Chromium also slimulales fatty acid and cholesterol synthesis from acetate in liver. Thai chromium is an essential cofaclor for the action of insulin on the rat lens was shown by Parkas in 1964. In the absence of the element, no significant insulin effect on glucose utilization of lens can be demonstrated. Chromium supplementation to the donor animals resulls in a significant response of lens tissue to the hormone. Numerous other findings indicate that chromium may play several vital roles in biological systems. 

Not all of the various chemical forms of chromium are effective in improving sugar metabolism, and the exact nature of the compound or compounds involved in activating insulin is not established. Some of the chromium in plants may not be present in nutritionally effective forms. Il has not been established that chromium is essential to plants, but high concentrations of the metal are toxic. Most agricultural crops, especially their seeds, contain only low levels of chromium. 

There is now much interest in the biology of chromium,1086"1088 which has been suggested to be involved not only in the action of insulin, but also in the activation of certain enzymes, and, possibly, the stabilization of nucleic acids. Chromium is also known to be carcinogenic and mutagenic at high concentrations, particularly as chromate. Chromate is reduced in rat liver microsomes to Crm and Crv. Crv is labile and may well be the carcinogenic form.1089... 

It has been proposed that GTF is related to a dinicotinatotris(amino acid)chromium(III) complex, which forms a ternary complex at the membrane receptor with insulin. Porcine insulin binds a Cr(nic)2(glutathione) complex very tightly. 

Chromium 2 mg 50-200 fig Potentiation of insulin, maintenance of normal glucose tolerance In malnutrition, aging, TPN impaired glucose tolerance, relative insulin resistance, elevated serum lipids, peripheral neuropathy Unknown15... 

A 54-year-old woman with gestational diabetes was later found to be allergic to chromium, pollen, dust, penicillin, acarbose, and metformin (130). She was treated with diet and glibenclamide, but later required insulin. With Humulin N insulin she developed a wheal of 15 mm immediately after the injection, which resolved in a few hours. However, a painful itchy induration appeared 2-3 hours after the injection and lasted a few days. She had an immediate reaction to isophane insulin, with induration, but insulin lispro was well-tolerated. 

In addition to vanadium, other early transition metals have been shown to have antidiabetic properties, which is not surprising, as this class of compounds would be expected to share some chemical functionality. Chromium [110-112], tungsten [113,114], and molybdenum [115,116] all have demonstrated insulin-like properties. 

Clodfelder, B.J., R.G. Upchurch, and J.B. Vincent. 2004. A comparison of the insulin-sensitive transport of chromium in healthy and model diabetic rats. J. Inorg. Biochem. 98 522-33. 

Brautigan, D.L., A. Kruszewski, and H. Wang. 2006. Chromium and vanadate combination increases insulin-induced glucose uptake by 3T3-L1 adipocytes. Biochem. Biophys. Res. Commun. 347 769-773. 

Chromium(III) is an essential nutrient required for normal energy metabolism. The National Research Council (NRC) recommends a dietary intake of 50-200 ig/day (NRC 1989). The biologically active form of an organic chromium(ni) complex, often referred to as GTF, is believed to function by facilitating the interaction of insulin with its cellular receptor sites. The exact mechanism of this interaction is not known (Anderson 1981 Evans 1989). Studies have shown that chromium supplementation in deficient and marginally deficient subjects can result in improved glucose, protein, and lipid metabolism. 

Administration of inorganic trivalent chromium compounds or extracts of brewers yeast resulted in decreased blood glucose levels and cholesterol levels and regression of atherosclerotic plaques (Pi-Sunyer and Offenbacher 1984). Improved insulin sensitivity also resulted in an increased incorporation of amino acids into proteins and cell transport of amino acid in rats receiving supplemental chromium (Roginski and Mertz 1969). 

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