Neuropathogenesis of Multiple Sclerosis and Huntington's Disease

Substantial epidemiological studies have established a link between environmental factors and prevalence of neurodegenerative diseases. Increasingly, some studies report a direct cause-and-effect relation between environmental agents such as heavy metals and pesticides, and some neurodegenerative disorders including multiple sclerosis (MS) and Huntington's disease (HD). Interestingly, high blood level of heavy metals and pesticides has been shown in patients with MS and HD. Those agents could be involved directly or indirectly in the pathogenesis of MS and HD. The underlying mechanisms may imply an immune breaking of self-tolerance or neurodegeneration onset of several neurotransmission systems. The chapter will discuss the role of different metals and pesticides in the onset and progress of MS and HD with an overview of the possible underlying pathomechanisms.