Manganese nervous system

Metabolic Functions. Manganese is essential for normal body stmcture, reproduction, normal functioning of the central nervous system, and activation of numerous enzymes (126). Synthesis of the mucopolysaccharide chondroitin sulfate involves a series of reactions where manganese is required in at least five steps (127). These reactions are responsible for formation of polysaccharides and linkage between the polysaccharide and proteins that form... 

The uptake of manganese by plants and its transport within plants has been reviewed. " Reviews describing Mn speciation in the blood and the transport kinetics of Mn into the central nervous system of mammals have appeared. Manganese has a unique capacity to be taken up via the olfactory pathways and pass trans-neuronally to other parts of the brain. ... 

Toxicology. The major concern of humans exposed to manganese is its effects on the central nervous system after chronic exposure. 

Wennberg A, Iregren A, Struwe G et al Manganese exposure in steel smelters a health hazard to the nervous system. Scand J Work Environ Health 17 255-262, 1991... 

Toxicology. Manganese tetroxide affects the central nervous system, and toxicity occurs mostly in chronic form (manganism). 

Toxicology. 2-Methylcyclopentadienyl manganese tricarbonyl (MMT) causes central nervous system effects and liver, kidney, and pulmonary damage in animals. 

Treatment of symptoms of idiopathic Parkinson s disease (paralysis agitans), postencephalitic parkinsonism, and sympathetic parkinsonism that may follow injury to the nervous system by carbon monoxide and manganese intoxication. 

Although trace amounts of manganese are essential for animals, in large quantities the metal can cause acute and chronic poisoning. Chronic inhalation of metal dust or fumes can cause manganism, a nonfatal disease affecting the central nervous system. The symptoms are mental disorder and disturbance in speech. 

Solvents, such as chlorinated hydrocarbons, toluene, benzene, and xylene, can cause a feeling of euphoria, but they can be deadly toxins. Small, daily doses may cause dizziness, mental confusion, and fatigue high doses will cause permanent damage to the central nervous system. Lead, mercury, and manganese ion poisoning will alter and destroy central and peripheral nerve function and cause personality changes. 

M. Aschner, K. E. Vrana, W. Zheng, Manganese uptake and distribution in the central nervous system (CNS), Neurotoxicology, 20 (1999), 173-180. 

R. T. Ingersoll, E. B. Montgomery, H. V. Aposhian, Central nervous system toxicity of manganese. II. Cocaine or reserpine inhibit manganese concentration in the rat brain. 

Manganese toxicity is also known to represent a serious health hazard to humans, with toxic intakes of the element (either through the air or diet) resulting in severe pathologies, particularly of the central nervous system (15-19). The first observation of Mn toxicity in humans was made by Couper in 1837 (15) (Table II), who reported a paralytic disease in workers of a pyrolusite (Mn dioxide) mill. 

Exposure to neurotoxicants or neurotoxic chemical substances causes severe adverse health effects to the nervous system, which is very sensitive to organometallic compounds and sulfide compounds. These compounds disrupt the normal functioning of the central nervous system, peripheral nerves or sensory organs, and the conduction of nerve impulses. Thus, chemical substances are considered neurotoxicants when they induce a consistent pattern of neural dysfunction. The chemical substances include but are not limited to carbon disulfide, manganese, methyl mercury, organic phosphorous insecticides, tetraethyl lead, thallium, and trialkyl tin compounds. 

The toxic effects of manganese in dogs (SEDA-21, 239) and humans (4) tend to involve the heart, liver, and nervous system, but some endocrine effects can occur. The general toxicity of manganese (5) and its neurotoxicity (6) have been reviewed. 

Feldman RG. Manganese. In de Wolff FA, editor. Intoxications of the Nervous System. Part I. Handbook Clin Neurol 1994 303-22. 

Brain extracellular concentrations of amino acids and divalent metals (e.g., manganese) are primarily regulated by astrocytes. Adequate glutamate homeostasis is essential for the normal functioning of the central nervous system (CNS), for example, glutamate is important for nitrogen metabolism and, along with aspartate, is the primary mediator of the excitatory... 

Other less potent naturally occurring substances exhibit neurotoxic effects when encountered in large concentration for sufficient periods of time. Examples include metals (arsenic, lead, mercury) and certain compounds containing these elements (methylmercu-ry) (Table 2). Some elements (manganese, selenium) and compounds (vitamin Bg) in this group, while neurotoxic in sustained heavy doses, are required in smaller amounts to support normal physiological function, including that of the nervous system. 

Elder A, Gelein R, Silva V, et al. Translocation of inhaled ultrafine manganese oxide particles to central nervous system. Environ Health Perspect 2006 114(8) 1172—8. 

Papp A, Pecze L, Vezer T. Acute effects of lead, mercury and manganese on the central and peripheral nervous system in rats in combination with alcohol exposure. ArhHigRada Tokiskol2005 56(3) 241 8 [abstract only—PubMed]. 

Mergler D, Huel G, Bowler R, Iregren A, Belanger S, Baldwin M, et al. Nervous system dysfunction among workers with long-term exposure to manganese. Environ Res 1994 64 151-80. 

Cawte J Psychiatric sequelae of manganese exposure in the adult, foetal and neonatal nervous systems. Aust N Z J Psychiatry 19 211-217, 1985... 

Canavan MM, Cobh S, Drinker CK Chronic manganese poisoning report of a case, with autopsy. Archives of Neurology and Psychiatry 32 501-512, 1934 Casamajor L An unusual form of mineral poisoning affecting the nervous system manganese JAMA 60 646-649,1913... 

Roels H, Lauwerys R, Buchet J-P, et al Epidemiological survey among workers exposed to manganese effects on lung, central nervous system, and some biological indices. Am J Ind Med 11 307-327,1987... 

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