RT Journal Article SR Electronic T1 Age-dependent protein abundance of cytosolic alcohol and aldehyde dehydrogenases in human liver JF Drug Metabolism and Disposition JO Drug Metab Dispos FD American Society for Pharmacology and Experimental Therapeutics SP dmd.117.076463 DO 10.1124/dmd.117.076463 A1 Deepak Kumar Bhatt A1 Andrea Gaedigk A1 Robin E. Pearce A1 J. Steven Leeder A1 Bhagwat Prasad YR 2017 UL http://dmd.aspetjournals.org/content/early/2017/06/12/dmd.117.076463.abstract AB Hepatic cytosolic alcohol and aldehyde dehydrogenases (ADHs and ALDHs) catalyze the biotransformation of xenobiotics (e.g., cyclophosphamide and ethanol) and vitamin A. Because age-dependent hepatic abundance of these proteins is unknown, we quantified protein expression of ADHs and ALDH1A1 in a large cohort of pediatric and adult human livers by LC-MS/MS proteomics. Purified proteins were used as calibrators. Two to three surrogate peptides per protein were quantified in trypsin digests of liver cytosolic samples and calibrator proteins under optimal conditions of reproducibility. Neonatal levels of ADH1A, ADH1B, ADH1C and ALDH1A1 were 3, 8, 146 and 3-fold lower than the adult levels, respectively. For all proteins, the abundance steeply increased during the first year of life, which mostly reached adult levels during early childhood (age between 1 to 6 years). Only for ADH1A protein abundance in adults (age >18 yrs.) was ~40% lower relative to the early childhood group. Abundances of ADHs and ALDH1A1 were not associated with gender in samples with age > 1 year compared to males. Known single nucleotide polymorphisms (SNPs) had no effect on the protein levels of these proteins. Quantification of ADHs and ALDH1A1 protein levels could be useful in predicting disposition and response of substrates of these enzymes in younger children.