If We Consider Parkinson's an Exaggeration of "Normal" Aging...
Many of the conditions that occur with age might be considered exaggerated forms of "normal" aging - one aspect of damage that has raced ahead in that person for some reason. In Parkinson's disease, this damage takes the form of a decline in dopamine-secreting cells in the brain. That happens to all people to some degree, but Parkinson's sufferers have a much greater loss of these vital cells. Here researchers demonstrate that a treatment for Parkinson's produces benefits for the same symptoms seen to a lesser degree in "normal" aging: "We wished to determine whether L-DOPA, a common treatment for the motor deficits in Parkinson's disease, could also reverse the motor deficits that occur during aging. We assessed motor performance in young (2-3 months) and old (20-21 months) male C57BL/6 mice using the challenge beam and cylinder tests. Prior to testing, mice were treated with L-DOPA or vehicle. Following testing, striatal tissue was analyzed for phenotypic markers of dopamine neurons: dopamine, dopamine transporter, and tyrosine hydroxylase. Although the dopaminergic markers were unchanged with age or L-DOPA treatment, L-DOPA reversed the motor deficits in the old animals such that their motor coordination was that of a young mice. These findings suggest that some of the locomotor deficits that accompany normal aging are responsive to L-DOPA treatment and may be due to subtle alterations in dopaminergic signaling."