Manganese and Movement Disorders: A Review

Abstract

Scientific and technological advances achieved with industrial expansion have led to an ever-increasing demand for heavy metals. This demand has, in turn, led to increased contamination of soil, water and air with these metals. Chronic exposure to metals may be detrimental not only to occupational workers but also to the nonoccupational population exposed to these metals. Manganese (Mn), a commonly used heavy metal, is an essential cofactor for many enzymatic processes that drive biological functions. However, it is also a potential source of neurotoxicity, particularly in the field of movement disorders. The typical manifestation of Mn overexposure is parkinsonism, which may be difficult to differentiate from the more common idiopathic Parkinson’s disease. In addition to environmental exposure to Mn, other potential etiologies causing hypermanganesemia include systemic health conditions, total parenteral nutrition and genetic mutations causing Mn dyshomeostasis. In this review, we critically analyze Mn and discuss its sources of exposure, pathophysiology and clinical manifestations. We have highlighted the global public health impact of Mn and emphasize that movement disorder specialists should record a detailed social and occupational history to ensure that a toxic etiology is not misdiagnosed as a neurodegenerative disease. In the absence of a definite therapeutic option, early diagnosis and timely institution of preventive measures are the keys to managing its toxic effects.

Environmental Impact on the Epigenetic Mechanisms Underlying Parkinson’s Disease Pathogenesis: A Narrative Review

“…PD risk has been shown to be lower in individuals who drink coffee [ 127 , 128 ]. However, there is also evidence that does not confirm this association [ 129 ].…”

Ayahuasca as a Decoction Applied to Human: Analytical Methods, Pharmacology and Potential Toxic Effects

“…However, in cases of overexposure, whether inhaled or ingested, Mn is highly toxic to several organ systems. Mn crosses the blood-brain barrier by the same mechanism as iron (Fe) [74,75]. Excessive exposure to Mn initially causes non-specific symptoms such as headache, irritability, fatigue, sleep disorders and emotional instability.…”

“…Excessive exposure to Mn initially causes non-specific symptoms such as headache, irritability, fatigue, sleep disorders and emotional instability. Later, a neurodegenerative syndrome with psychiatric symptoms, called manganism, may develop, which is characterized not only by problems with speech, gait and balance, but also with obsessive-compulsive behavior, hostility, mood swings, psychotic experiences such as hallucinations and paranoid ideas, and reduced cognitive flexibility [74,76,77]. Some ayahuasca decoctions may even contain heavy metals, such as lead or cadmium, which are not recommended at all to be consumed.…”

Differentiating Wild and Apiary Honey by Elemental Profiling: a Case Study from Mangroves of Indian Sundarban

“…Manganese (Mn) is an essential and abundant element whose misapplication and overexploitation hampers the concentration balance in ecosystem and causes several natural mess and health disorders [74][75][76]. The maximum, minimum and average concentration of Mn in wild-derived honey samples were 32.12 mg/kg (Samsernagar-HW13), 0.04 mg/kg (Bakkhali-HW2) and 5.25 ± 8.45 mg/kg respectively whereas honey samples were derived from apiarists; the above mentioned concentrations were 14.32 mg/kg (Samsernagar-HA13), 0.09 mg/kg (Nimpith-HA10) and 4.61 ± 3.87 mg/kg.…”