Modulation of cholinergic systems by manganese

Yoram Finkelstein, Dejan Milatovic, Michael Aschner

Research output: Contribution to journalReview article

62 Scopus citations

Abstract

Information on changes in the central nervous system (CNS) cholinergic systems following exposure to manganese are considerably less extensive than that associated with other neurotransmitter systems. However, experimental and clinical evidence support the notion that cholinergic activity plays a key role in the pathophysiology of manganese-induced neurotoxicity. Manganese acts as a chemical stressor in cholinergic neurons in a region-specific manner causing breakdown of the cellular homeostatic mechanisms. In fact, a number of cholinergic synaptic mechanisms are putative targets for manganese activity: presynaptic choline uptake, quantal release of acetylcholine into the synaptic cleft, postsynaptic binding of acetylcholine to receptors and its synaptic degradation by acetylcholinesterase. Moreover, manganese significantly influences astrocytic choline transport systems and astrocytic acetylcholine-binding proteins. Thus, manganese exerts its effect on the highly dynamic reciprocal relationship between astrocytes and cholinergic neurons. Cholinergic afferents are crucial in the physiology of locomotion, cognition, emotion and behavioral response, and therefore, it is not surprising that the anatomical selectivity of most manganese-induced cholinergic effects is compatible with the clinical correlates of manganism, which involves impairment of emotional response, decline in higher cortical functions and movement disorder. Manganism, also referred to as Parkinson's-like disorder, is initially manifested by a neuropsychiatric syndrome (locura manganica), the most frequent symptoms and signs of which are compulsive behavior, emotional lability, visual hallucinations and flight of ideas, cognitive decline and memory loss. These signs and symptoms are followed by an extrapyramidal syndrome, which shares numerous clinical and pathophysiological characteristics with idiopathic Parkinson's disease (PD). This natural history of disease could be a clinical reflection of the preferential involvement of the cholinergic systems, initially in the septo-hippocampus and later in the basal ganglia. These observations highlight the importance of studying the role of the CNS cholinergic systems in manganese-mediated neurotoxicity.

Original languageEnglish (US)
Pages (from-to)1003-1014
Number of pages12
JournalNeurotoxicology
Volume28
Issue number5 SPEC. ISS.
DOIs
StatePublished - Sep 2007
Externally publishedYes

Keywords

  • Acetyl cholinesterase
  • Acetylcholine
  • Choline uptake
  • Manganese
  • Muscarinic receptors
  • Parkinsonism

ASJC Scopus subject areas

  • Neuroscience(all)
  • Toxicology

Fingerprint Dive into the research topics of 'Modulation of cholinergic systems by manganese'. Together they form a unique fingerprint.

  • Cite this