Sally Stabler, MD

Website: http://www.ncbi.nlm.nih.gov/pubmed?term="Stabler SP"[Author]

For Patients:
My research focuses on: - Anemia - Cytopenias - Chronic leukemias - Myeloproliferative diseases - Congenital bleeding disorders - Hematology - Internal medicine - Medical oncology

For Referring Providers:
Dr. Stabler began her research career in the laboratory of Robert H. Allen, M.D. at the University of Colorado Medical School studying enzymes in vitamin B12-dependent pathways. Together they made the discoveries that homocysteine was a sensitive and specific marker of both vitamin B12 and folate deficiency and that methylmalonic acid elevations could be used to distinguish between the two deficiencies. Over the past three-decades, Drs. Stabler has pursued most aspects of folate, vitamins B12 and B6 and methionine metabolism in the laboratory and in clinical studies. The highly sensitive and specific stable isotope dilution gas chromatography/mass spectrometry assays developed in the hematology laboratories have been used to study animal models of vitamin deficiency, genetic knock-outs or perturbed metabolism as well as large cohorts of patients studied in collaboration with many national and even international groups. Use of these assays have shown that the serum vitamin levels are much less sensitive and specific than widely recognized, and that the pattern of clinical abnormalities in B12 deficiency is broader than expected. She has also developed sensitive and specific liquid chromatography/mass spectrometry assays for S-adenosylhomocysteine and S-adenosylmethionine and studied these in both animal and human models of perturbed vitamin metabolism. Her studies of methionine metabolism have ranged from stroke, markers of frailty and cognition in seniors, O2 induced lung damage, inflammatory bowel disease, vascular diseases, effects of homocysteine-lowering agents and cancer susceptibility in large cohorts, to name a few. She demonstrated that large doses of commonly used supplements such as alpha-lipoic acid caused rapid depletion of S-adenosylmethionine and increases in S-adenosylhomocysteine, the inhibitor of many important methylation reactions. Dr. Stabler had a long-standing collaboration with S. Harvey Mudd of the NIH until his passing in 2014. During this 15-year collaboration she used her panel of methionine metabolites to help pinpoint the abnormalities in known inborn errors of methionine metabolism but also helped describe two other new disorders; glycine N-methyltransferase deficiency and S-adenosylhomocysteine hydrolase deficiency. The pattern of methionine-related metabolites was also demonstrated in more common disorders such as methionine adenosyl-transferase deficiency, cystathionine-beta synthase deficiency, cystathionase deficiency and in disorders not directly related to methionine metabolism such as DGUOK and other mitochondrial DNA deficiency disorders. Dr. Stabler has participated in the diagnosis and follow-up of many patients with inborn errors of folate, vitamin B12 and methionine metabolism through direct measurement of the relative metabolites in patient samples and providing interpretations on baseline and follow-up samples. Many of these lab assays are not available as diagnostic tests and the clinicians in metabolic clinics approach her directly for help in diagnosis. Dr. Stabler has recently developed a stable isotope assay for 2-hydroxy-glutarate, a metabolite that can be used as a marker of IDH mutations commonly found in malignant disease. Dr. Stabler has developed assays for free fatty acids that can be measured in body fluids and feces in models such as inflammatory bowel disease.