Assessment of plasma lactoferrin in Parkinson's disease

Iron may play an important role in the pathogenesis of Parkinson's disease (PD). Recent studies have shown that the iron-transporting glycoprotein lac toferrin (LF) and its receptor are increased in the substantia nigra (SN) i n PD. We investigated whether plasma levels of LF are altered in dopa-respo nsive PD. Plasma LF was not different between patients with PD (n = 23: 306 +/- 116 [mean +/- standard deviation] ng/ml) and age- and sex-matched heal thy control subjects(n = 15: 359 +/- 126 ng/ml ). However, LF was inversely correlated with PD severity (r = -0.68. P = 0.002), an association that re mained significant after adjustment for treatment with levodopa. monoaminoo xidase inhibitors, and dopa agonists (r = -0.53 P = 0.017). Plasma transfer rin and ferritin levels were not different between groups and neither corre lated with disease severity nor with LF levels. Together with the result of increased nigral lactoferrin, this finding is compatible with the hypothes is of an imbalance between LF levels in blood and SN in progressing PD. Lar ger and particularly longitudinal studies and measurements of LF in cerebro spinal fluid are warranted to further examine the role of LF in PD.