118 Manganese Manganese is an essential trace nutrient in all forms of life. Physiologically, it. exists as an ion in the body. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. 7439-96-5 27854 Mn 54.938049 White powder. 1244°C 2095°C (3803°F) Oral (L228) ; inhalation (L228) Manganese is a cellular toxicant that can impair transport systems, enzyme activities, and receptor functions. It primarily targets the central nervous system, particularily the globus pallidus of the basal ganglia. It is believed that the manganese ion, Mn(II), enhances the autoxidation or turnover of various intracellular catecholamines, leading to increased production of free radicals, reactive oxygen species, and other cytotoxic metabolites, along with a depletion of cellular antioxidant defense mechanisms, leading to oxidative damage and selective destruction of dopaminergic neurons. In addition to dopamine, manganese is thought to interact with other neurotransmitters, such as GABA and glutamate. Manganese overwhelms the manganese superoxide dismutase and produce oxidative damage. The neurotoxicity of Mn(II) has also been linked to its ability to substitute for Ca(II) under physiological conditions. It can enter mitochondria via the calcium uniporter and inhibit mitochondrial oxidative phosphorylation. It may also inhibit the efflux of Ca(II), which can result in a loss of mitochondrial membrane integrity. Mn(II) has been shown to inhibit mitochondrial aconitase activity to a significant level, altering amino acid metabolism and cellular iron homeostasis. (L228) Manganese is mainly absorbed via ingestion, but can also be inhaled. It binds to alpha-2-macroglobulin, albumin, or transferrin in the plasma and is distributed to the brain and all other mammalian tissues, though it tends to accumulate more in the liver, pancreas, and kidney. Manganese exists in a number of oxidation states and is believed to undergo changes in oxidation state within the body. Manganese oxidation state can influence tissue toxicokinetic behavior, and possibly toxicity. Manganese is excreted primarily in the faeces. (L228) LD50: 9 g/kg (Oral, Rat) (T26) No indication of carcinogenicity to humans (not listed by IARC). Manganese is used principally in steel production to improve hardness, stiffness, and strength. It may also be used as an additive in gasoline to improve the octane rating of the gas. Manganese ions have various colors and are used industrially as pigments. (L228, L229) Chronic Inhalation: 0.0003 mg/m3 (L134) Manganese mainly affects the nervous system and may cause behavioral changes and other nervous system effects, which include movements that may become slow and clumsy. This combination of symptoms when sufficiently severe is referred to as “manganism”. High levels of manganese may also cause damage to the reproductive system. (L228) Manganese mainly affects the nervous system and may cause behavioral changes and other nervous system effects, which include movements that may become slow and clumsy. This combination of symptoms when sufficiently severe is referred to as “manganism”. (L228) 2009-03-06T18:58:06Z 2014-12-24T20:21:08Z Alpha-2-macroglobulin (P01023) Serum albumin (P02768) Serotransferrin (P02787) Superoxide dismutase [Mn], mitochondrial (P04179) (L228) http://en.wikipedia.org/wiki/Manganese C19610 153550 173470 29035 MN%2b3 D008345 Manganese MN 6475 true Superoxide dismutase [Mn], mitochondrial (P04179) (L228) Alpha-2-macroglobulin (P01023) Serum albumin (P02768) Serotransferrin (P02787) (L228) [Mn++] Mn InChI=1S/Mn/q+2 InChIKey=WAEMQWOKJMHJLA-UHFFFAOYSA-N 54.9369 54.936952476 Exogenous Solid HMDB01333 25916