As a post-doctoral fellow, and later an Assistant Professor of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, Dr. Thaden’s interests were in basic research of determinants of lifespan and the intrinsic rate of aging. He used a genetically and biochemically facile animal model system, Caenorhabditis elegans, and the tools of both molecular genetics and bioanalytical chemistry in this work.
Also at UAMS, in late 2002, Dr. Thaden co-founded, and for five years managed the UAMS Core for Small Molecule Mass Spectrometry. Once operational, this laboratory analyzed ~8,000 samples/year using small-molecule LC/MS/MS and GC/MS methods. Among the LC/MS/MS methods he developed were assays lipid peroxidation measuring 4-hydroxynonenal; of lipid enzymatic cyclooxygenation measuring a set of hydroxylated lypids (HETEs, HODEs), and of herbal supplement inhibition of a liver P450 enzyme, measuring the enzyme’s activity on an administered benzodiazepine reporter molecule. He also adapted a GC/MS method for globally surveying small metabolite levels in plasma (metabolomics). Also at UAMS, he was de facto thesis advisor to two graduate students, co-creator/co-instructor of a workshop on the R Statistical Language, and a guest lecturer in courses at the Mid-South Bioinformatics Center, University of Arkansas at Little Rock.
Beginning at UAMS, and now here at Texas A&M University, Dr. Thaden is the chief analytical chemist in the laboratory of the Center for Translational Research in Aging and Longevity. He develops and implements chromatography/mass spectrometry assays that simultaneously measure endogenous small molecules and exogenously added stable-isotopic variants of those molecules, thus allowing calculations of their metabolic flux and fate. Examples include L-arginine and L-citrulline in the nitric oxide pathway, L-phenylalanine, L-leucine and overall amino acids in protein synthesis and clearance; urea and metabolites of L-tryptophan. Analyzed specimens include blood, biopsy tissue, protein hydrolyzates, and urine. While at CTRAL, Dr. Thaden helped secure funding for two high-end chromatography/mass spectrometry systems and researched the selection and installation of a total of four. The amino acid assay has been particularly productive, able to measure up to 80 unique chemical/isotopic entities and averaging over 400 such analyses per week. Please click here for Dr. Thaden’s publications.