TY - JOUR
T1 - A sensitive and specific LC-MS/MS method for rapid diagnosis of Niemann-Pick C1 disease from human plasma
AU - Jiang, Xuntian
AU - Sidhu, Rohini
AU - Porter, Forbes D.
AU - Yanjanin, Nicole M.
AU - Speak, Anneliese O.
AU - Te Vruchte, Danielle Taylor
AU - Platt, Frances M.
AU - Fujiwara, Hideji
AU - Scherrer, David E.
AU - Zhang, Jessie
AU - Dietzen, Dennis J.
AU - Schaffer, Jean E.
AU - Ory, Daniel S.
PY - 2011/7
Y1 - 2011/7
N2 - Niemann-Pick type C1 (NPC1) disease is a rare, progressively fatal neurodegenerative disease for which there are no FDA-approved therapies. A major barrier to developing new therapies for this disorder has been the lack of a sensitive and noninvasive diagnostic test. Recently, we demonstrated that two cholesterol oxidation products, specifically cholestane-3β,5α, 6β-triol (3β,5α,6β-triol) and 7- ketocholesterol (7-KC), were markedly increased in the plasma of human NPC1 subjects, suggesting a role for these oxysterols in diagnosis of NPC1 disease and evaluation of therapeutics in clinical trials. In the present study, we describe the development of a sensitive and specific LC-MS/MS method for quantifying 3β,5α,6β- triol and 7-KC human plasma after derivatization with N,N-dimethylglycine. We show that dimethylglycine derivatization successfully enhanced the ionization and fragmentation of 3β,5α,6β-triol and 7-KC for mass spectrometric detection of the oxysterol species in human plasma. The oxysterol dimethylglycinates were resolved with high sensitivity and selectivity, and enabled accurate quantification of 3β,5α,6β-triol and 7-KC concentrations in human plasma. The LC-MS/MS assay was able to discriminate with high sensitivity and specificity between control and NPC1 subjects, and offers for the first time a noninvasive, rapid, and highly sensitive method for diagnosis of NPC1 disease.
AB - Niemann-Pick type C1 (NPC1) disease is a rare, progressively fatal neurodegenerative disease for which there are no FDA-approved therapies. A major barrier to developing new therapies for this disorder has been the lack of a sensitive and noninvasive diagnostic test. Recently, we demonstrated that two cholesterol oxidation products, specifically cholestane-3β,5α, 6β-triol (3β,5α,6β-triol) and 7- ketocholesterol (7-KC), were markedly increased in the plasma of human NPC1 subjects, suggesting a role for these oxysterols in diagnosis of NPC1 disease and evaluation of therapeutics in clinical trials. In the present study, we describe the development of a sensitive and specific LC-MS/MS method for quantifying 3β,5α,6β- triol and 7-KC human plasma after derivatization with N,N-dimethylglycine. We show that dimethylglycine derivatization successfully enhanced the ionization and fragmentation of 3β,5α,6β-triol and 7-KC for mass spectrometric detection of the oxysterol species in human plasma. The oxysterol dimethylglycinates were resolved with high sensitivity and selectivity, and enabled accurate quantification of 3β,5α,6β-triol and 7-KC concentrations in human plasma. The LC-MS/MS assay was able to discriminate with high sensitivity and specificity between control and NPC1 subjects, and offers for the first time a noninvasive, rapid, and highly sensitive method for diagnosis of NPC1 disease.
KW - Cholesterol
KW - Diagnostic tools
KW - Liquid chromatography/tandem mass spectrometry
KW - Neurodegeneration
KW - Niemann-Pick disease
KW - Oxysterols
UR - http://www.scopus.com/inward/record.url?scp=79959232858&partnerID=8YFLogxK
U2 - 10.1194/jlr.D015735
DO - 10.1194/jlr.D015735
M3 - Article
C2 - 21518695
AN - SCOPUS:79959232858
SN - 0022-2275
VL - 52
SP - 1435
EP - 1445
JO - Journal of lipid research
JF - Journal of lipid research
IS - 7
ER -