Metal hair as early biomarker of Parkinson-like disease

Hair is a non-invasive biological material useful in the bio monitoring of metals and microelements because it is a vehicle of excretion of substances from the human body (1). Heavy metals, whose concentrations are up to 10-fold higher than the levels found in blood or urine, have an high affinity to hair mainly due to the presence of cystine, and metallic cations form bonds with the sulphur of the keratin matrix of the hair. The value of human hair as matrices for environmental monitoring has been accepted also by Environmental Protection Agency (EPA). Neurodegenerative diseases are characterized by some similar critical processes, such as oxidative stress, protein aggregations, mitochondrial dysfunctions. Energy failure and metal ion imbalance mediates or triggers these processes leading to neurodegeneration and cell death. Epidemiological indications suggest that the exposure to neurotoxin agents (i.e. pesticide, Cu, Fe, Mn, etc) during pregnancy and early childhood is involved in the neurodevelopmental disorders and subclinical brain dysfunction (2). During early age, when the neurodevelopmental process is the most rapid/intense, individuals may be more susceptible to pollutants, leading to potential effects on the brain even at very low doses. Our previous studies indicated that pup rats treated with the pyrethroid insecticide permethrin, during brain development (from 6th to 15th day of life) develop long term effects leading to a Parkinson-like disease (PD) (3). With the aim of improve the knowledge on biomarkers useful to monitoring the development of neurodegeneration, hairs from neck of the rat model of PD were analysed with ICP-MS instrumentation previous treatment of samples with closed vessel mineralization in acidic conditions. Results show a significant decrease of Se, Hg and Sn, while Cu resulted increased.