Liquid chromatographic-atmospheric pressure chemical ionization mass spectrometric analysis of glycine conjugates and urinary isovalerylglycine in isovaleric acidemia.
n-Acetylglycine, n-propionylglycine, n-butyrylglycine, isobutyrylglycine, n-valerylglycine, isovalerylglycine, heptanoylglycine, phenylacetylglycine and isovalerylglucuronide were identified based on their liquid chromatographic-atmospheric pressure chemical ionization mass spectra (LC-APCI-MS). We were able to detect the presence of urinary isovalerylglycine in two cases of isovaleric acidemia using LC-APCI-MS. Membrane-filtered urine samples were injected into the LC-APCI-MS system in the negative-ion mode without any further pretreatment, and large amounts of isovalerylglycine were detected as the [M-H]- ion. The urinary excretion of isovalerylglycine appeared to increase after L-carnitine therapy. This analytical method is quick and easy and it may be a useful tool in understanding dysfunctional conditions in isovaleric acidemia.
Department of Pediatrics, Nagoya City University Medical School, Japan.
T
T
Ito
K
K
Kidouchi
N
N
Sugiyama
M
M
Kajita
T
T
Chiba
T
T
Niwa
Y
Y
Wada
D000138:Acidosis / Q000097:blood* / Q000652:urine*; D000284:Administration, Oral; D002331:Carnitine / Q000494:pharmacology / Q000652:urine; D002675:Child, Preschool; D002853:Chromatography, Liquid; D005260:Female; D005965:Glucuronates / Q000652:urine; D005998:Glycine / Q000031:analogs & derivatives* / Q000652:urine; D045782:Hemiterpenes; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D013058:Mass Spectrometry; D010421:Pentanoic Acids / Q000097:blood*
D005965:Glucuronates; D045782:Hemiterpenes; D010421:Pentanoic Acids; C008216:isovaleric acid; C005916:N-isovalerylglycine; D002331:Carnitine; D005998:Glycine