Ashley Cowart, Ph.D.
Assistant Professor
Biochemistry and Molecular Biology

2005               Research Health Scientist, Ralph H. Johnson VA Medical Center
2001-2005      Postdoctoral Fellowship, Dr. Yusuf Hannun, Biochemistry, MUSC

Education
2001               Ph.D., Biochemistry, Vanderbilt University
1995               B.S., Biology, Furman University

Contact Info
Email: cowartl@musc.edu
Office: 423 Strom Thurmond Building
Lab: 441 Strom Thurmond Building
Phone: 843-789-6796

Research Interests

Our laboratory studies how plasma lipids affect tissue sphingolipid metabolism. This is important because obesity and diabetes increase plasma lipid concentrations, and this increase has been demonstrated to change sphingolipid profiles in tissues including adipose, liver, skeletal muscle, and heart. In fact, elevation of plasma lipids probably contributes to pathologies observed in these tissues from diabetic patients. We hypothesize that aberrant sphingolipid synthesis promotes tissue pathologies including inflammation, muscle wasting, and cardiac hypertrophy. To address this hypothesis we use a combination of tissue culture and rodent models. Placing rodents on a high-fat diet increases plasma fatty acids and dramatically impacts tissue sphingolipids. These changes precipitate major changes in gene regulation and signaling pathways. We have dissected some of these changes using microarrays, and with collaborators in the department of Biostatistics, Bioinformatics, and Epidemiology, we also are actively developing novel bioinformatics strategies for co-analysis of gene expression data from microarrays and sphingolipid levels from lipidomics analysis. These strategies have allowed us to find “needles” in the “haystack” of lipid-mediated cell signaling.

Recent Publications | Additional Publications

1: Richards AJ, Muller B, Shotwell M, Cowart LA, Rohrer B, Lu X. Assessing the functional coherence of gene sets with metrics based on the Gene Ontology graph. Bioinformatics. 2010 Jun 15;26(12):i79-87. PubMed PMID: 20529941; PubMed Central PMCID: PMC2881388.


2: Cowart LA, Shotwell M, Worley ML, Richards AJ, Montefusco DJ, Hannun YA, Lu X.Revealing a signaling role of phytosphingosine-1-phosphate in yeast. Mol Syst Biol. 2010;6:349. Epub 2010 Feb 16. PubMed PMID: 20160710; PubMed Central PMCID: PMC2835565.


3: Hu W, Bielawski J, Samad F, Merrill AH Jr, Cowart LA. Palmitate increases sphingosine-1-phosphate in C2C12 myotubes via upregulation of sphingosine kinase message and activity. J Lipid Res. 2009 Sep;50(9):1852-62. Epub 2009 Apr 15. PubMed PMID: 19369694; PubMed Central PMCID: PMC2724779.


4: Kitagaki H, Cowart LA, Matmati N, Montefusco D, Gandy J, de Avalos SV, Novgorodov SA, Zheng J, Obeid LM, Hannun YA. ISC1-dependent metabolic adaptation reveals an indispensable role for mitochondria in induction of nuclear genes during the diauxic shift in Saccharomyces cerevisiae. J Biol Chem. 2009 Apr 17;284(16):10818-30. Epub 2009 Jan 29. PubMed PMID: 19179331; PubMed Central
PMCID: PMC2667769.


5: Brice SE, Alford CW, Cowart LA. Modulation of sphingolipid metabolism by the phosphatidylinositol-4-phosphate phosphatase Sac1p through regulation of phosphatidylinositol in Saccharomyces cerevisiae. J Biol Chem. 2009 Mar 20;284(12):7588-96. Epub 2009 Jan 12. PubMed PMID: 19139096; PubMed Central PMCID: PMC2658053.