While the beneficial effect of levodopa on traditional motor control tasks have been well documented over the decades, its effect on speech motor control has rarely been objectively examined and the existing literature remains inconclusive. This paper aims to examine the effect of levodopa on speech in patients with Parkinson's disease. It was hypothesized that levodopa would improve preparator...

This Medicine Update is for people with Parkinson's disease who are taking, or thinking about taking, rasagiline. Independent, not-for-profit and evidence based, NPS enables better decisions about medicines and medical tests. We are funded by the Australian Government Department of Health and Ageing. Summary Rasagiline is a medicine that has recently been made available in Australia for the tre...

Oral levodopa remains the most effective symptomatic drug for Parkinson’s disease (PD); however, its long-term use is limited by the emergence of motor fluctuations and involuntary movements, particularly in young-onset patients. A growing number of preclinical and clinical studies suggest that non-physiological pulsatile stimulation of striatal dopamine (DA) receptors induced by the use of sho...

Both methylenetetrahydrofolate (MTHFR) C677T genotype and levodopa treatment may give rise to elevated serum homocysteine levels in parkinsonian patients. We aimed to clarify the interplay of these factors in pathogenesis of Parkinson’s disease (PD)-related hyperhomocysteinemia. Total serum levels of homocysteine (tHcy) and MTHFR C677T genotype were investigated in levodopa-treated and -untreat...

BACKGROUND Postural stability analysis has shown that postural control is impaired in untreated idiopathic Parkinson's disease (IPD), even in the early stages of the disease. Vascular Parkinson's disease (VPD) lacks consensus clinical criteria or diagnostic tests. Moreover, the levodopa effect on postural balance remains undefined for IPD and even less so for VPD. OBJECTIVE To characterize po...

Levodopa (in combination with a peripheral dopadecarboxylase inhibitor) substantially improves the quality of life of patients. However, physicians are not always comfortable prescribing it, and its administration is often delayed to retard the development of motor complications or is restricted to patients with relatively advanced disease, because there is a fear that the decreased response of...

Ca(2+)/calmodulin-dependent protein kinase II is a synapse-enriched kinase in mammalian brains. This kinase interacts with various synaptic proteins to regulate expression and function of interacting proteins and thereby modulates synaptic transmission. CaMKII and its interacting partners are also believed to play a pivotal role in the pathogenesis of various neurological and neurodegenerative ...

Levodopa-induced dyskinesias (LIDs) are the most common and disabling adverse motor effect of therapy in Parkinson's disease (PD) patients. In this study, we investigated serotonergic mechanisms in LIDs development in PD patients using 11C-DASB PET to evaluate serotonin terminal function and 11C-raclopride PET to evaluate dopamine release. PD patients with LIDs showed relative preservation of s...

Currently, there is no drug that has proven neuroprotective properties in Parkinson's disease. The best-known levodopa, which acts as inhibitors of the MAO-B and COMT enzymes involved dopamine degradation. Although levodopa "gold standard" treatment, disease progresses, most patients develop complications from therapy side effects. In this sense, combination two abundant substances phytotherapi...