Crosstalk in human brain between globoid cell leucodystrophy and zinc-alpha-2-glycoprotein (ZAG), a biomarker of lipid catabolism

Zinc-alpha-2-glycoprotein (ZAG) is a protein identified as a lipid-mobilizing factor participating in a lipid catabolism. In spite of intensive studies conducted during last five decades, the role of this protein in processes of neurodegeneration remains unclear. The aim of our study was to examine the presence of ZAG protein in the brain of patients with Krabbe’s disease, which is considered as a psychosine lipidosis caused by a mutation of a known gene. We found intracellular and extracellular localization of ZAG in the brain of Krabbe’s disease patients but in the brain of control age-matched patients, ZAG was not detected. Distribution of ZAG in the brain suggests that the influx of ZAG into the brain involved a blood-brain barrier mechanism and adenoreceptors localized on astrocytes and some neurons.