Identification and Evaluation of Biomarkers for Niemann-Pick Disease Type C Based on Chemical Analysis Techniques

Niemann–Pick disease type C (NPC) is an autosomal recessive disorder that features progressive neurodegeneration. Because NPC patients have mutations in NPC1 or NPC2 cholesterol transporting proteins, failures in cholesterol and other lipid trafficking occur. NPC patients represent a wide clinical spectrum in terms of age of onset and type of symptoms. Because conventional diagnostic methods are time-consuming and complicated, biomarker tests have attracted increased attention. In this review, recently reported biomarkers for NPC are discussed in detail. For example, oxysterols and some cholenoic acid conjugates, metabolized from excess cholesterol in NPC cells, can be detected in urine or plasma. In addition, two types of lysosphingolipids, sphingosylphosphorylcholine and glycosylsphingosine, are present at increased concentrations in NPC patients. A more recently discovered biomarker is N-palmitoyl-O-phosphorylcholine, previously called “lysosphingomyelin-509.” These biomarkers are helpful for the early diagnosis of NPC and may contribute to a good prognosis for NPC patients.