The Elevated Brain Manganese Concentration Induced Neurotoxicity: Review

Abstract

Manganese (Mn) is an essential trace element and it is required for many ubiquitous enzymatic reactions. While Mn
deficiency rarely occurs in humans, Mn toxicity is known to occur in certain occupational settings through inhalation of
Mn-containing dust. The brain is particularly susceptible to this excess Mn and accumulation there can cause a neurodegenerative disorder known as manganism. Characteristics of this disease are described as Parkinson-like symptoms.
The similarities between the two disorders can be partially explained by the fact that the basal ganglia accumulate most
of the excess Mn compared with other brain regions in manganism, and dysfunction in the basal ganglia is also the etiology of Parkinson's disease. The mechanisms by which increased Mn levels can cause neuronal dysfunction are yet to
be elucidated. However, emerging studies are beginning to provide significant evidence of Mn effects on cortical structures and cognitive function at lower levels than previously recognized.