Abstract
We searched for drugs that alleviate the reduction of dopaminergic neurons caused by the administration of lipopolysaccharide (LPS) to the substantia nigra of the rat brain. Human milk fat globule-EGF factor 8 protein (MFG-E8) is similar to MFG-E8-S, a short isoform, of the mouse MFG-E8. However, the function of MFG-E8-S was not clear. Rats with LPS-induced Parkinson's disease were prepared and the effects of human MFG-E8 were examined. MFG-E8 improved the significant reduction in mesencephalic dopamine neurons induced by the administration of LPS. LPS was administered to human induced pluripotent stem cell (iPSC)-derived dopaminergic neurons to induce inflammation and the effect of MFG-E8 was examined. MFG-E8 showed no toxicity toward neurons. We reanalyzed the results using public microarray data. MFG-E8 mRNA was found to be expressed in all parts of the body, particularly by adipose-derived stem cells (ADSCs). Furthermore, we investigated the culture supernatant of ADSCs using the liquid chromatography-tandem mass spectrometry (LC⁻MS/MS) analysis method and successfully identified the peptide of the MFG-E8 F5/8 type C domain. The results suggested that MFG-E8-S may have a preventive effect against Parkinson's disease.