Neurotoxicity manganese

Graham, D.G. Catecholamine toxicity A proposal for the molecular pathogenesis of manganese neurotoxicity and Parkinson s disease. Neurotoxicology 5 83-86, 1984. 

The mitochondrial dysfunctionality seen in manganese neurotoxicity might be related to the accumulation of reactive oxygen species (Verity, 1999). Mitochondrial Mn superoxide dismutase (MnSOD) is found to be low or absent in tumour cells and may act as a tumour suppressor. It is induced by inflammatory cytokines like TNF, presumably to protect host cells. In a rat model, iron-rich diets were found to decrease MnSOD activity, although a recent study reported that in rat epithelial cell cultures iron supplementation increased MnSOD protein levels and activity, but did not compromise the ability of inflammatory mediators like TNF to further increase the enzyme activity (Kuratko, 1999). 

Dll. Donaldson, J., LaBella, F. S., and Gesser, D. Enhanced autooxidation of dopamine as possible basis of manganese neurotoxicity. Neurotoxicology 1, 53-64 (1981). 

Pal PK, Samri A, Caine DB. Manganese neurotoxicity a review of clinical features, imaging and pathology. Neurotoxicology 1999 20(2-3) 227-38. 

Erikson KM and Aschner M (2003) Manganese neurotoxicity and glutamate-GABA interaction. Neurochemistry International 43 475-480. 

Barron TF, Devenyi AG, Mamourian AC Symptomatic manganese neurotoxicity in a patient with chronic liver disease correlation of clinical symptoms with MRI findings. Pediatr Neurol 10 145-148,1994... 

Donaldson J, Barbeau A Manganese neurotoxicity possible clues to the etiology of human brain disorders, in Metal Ions in Neurology and Psychiatry. Edited by Gabay S, Harris J, Ho BT. New York, Alan R Liss, 1985, pp 259-285... 

The central nervous system is the primary target of manganese toxicity. Although it is known that manganese is a cellular toxicant that can impair transport systems, enzyme activities, and receptor functions, the principal manner in which manganese neurotoxicity occurs has not been clearly established (Aschner and Aschner 1991). 

Elderly people might also be somewhat more susceptible to manganese neurotoxicity than the general population. Neurological effects were observed in older persons consuming manganese levels similar to levels found in U.S. surface and groundwaters (Deveral and Mellard 1988 EPA 1984 Kondakis et al. 

Studies in rodents and nonhuman primates indicate that oral intake of high doses of manganese can lead to biochemical and behavioral changes indicative of nervous system effects (Bonilla and Prasad 1986 Chandra 1983 Gupta et al. 1980 Kristensson et al. 1986 Lai et al. 1984 Nachtman et al. 1986), and this is supported by intravenous studies in monkeys (Newland and Weiss 1992). Rodents do not appear to be as susceptible to manganese neurotoxicity as humans however, a study by Newland and Weiss (1992) indicates that Cebus monkeys would be a reasonable animal model. Further studies in animals may help determine the basis for the apparent differences in route and species susceptibility. 

Ali MM, Murthy RC, Mandal SK, et al. 1985. Effect of low protein diet on manganese neurotoxicity III. Brain neurotransmitter levels. Neurobehav Toxicol Teratol 7 427-431. 

Aschner M, Aschner JL. 1991. Manganese neurotoxicity Cellular effects and blood-brain barrier transport. Neurosci Biobehav Rev 15 333-340. 

Donaldson J, LaBella FS, Gesser D. 1980. Enhanced autoxidafion of dopamine as a possible basis of manganese neurotoxicity. Neurotoxicity 2 53-64. 

Donaldson J, McGregor D, LaBella F. 1982. Manganese neurotoxicity A model for free radical mediated neurodegenerafion Can J Physiol Pharmacol 60 1398-1405. 

Iregren A. 1999. Manganese neurotoxicity in industrial exposures Proof of effects, critical exposure level, and sensitive tests. Neurotoxicology 20 315-324. 

Mergler D, Baldwin M, Bdlanger S, et al. 1999. Manganese neurotoxicity, a continuum of dysfunction Results from a community based study. Neurotoxicology 20 327-342. 

Parenti M, Rusconi L, Cappabianca V, et al. 1988. Role of dopamine in manganese neurotoxicity. Brain Res 473 236-240. 

Zheng W, Ren S, Graziano JH. 1998. Manganese inhibits mitochondrial aconitase a mechanism of manganese neurotoxicity. Brain Res 799 334-342. 

Mergler D and Baldwin M (1997) Early manifestations of manganese neurotoxicity in humans an update. Environ Res 73 92-100. 

Verity MA (1999) Manganese neurotoxicity a mechanistic hypothesis. Neurotoxicology 20 489— 497. 

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