David B. Lombard, M.D., Ph.D.
Assistant Professor of Pathology
Assistant Research Professor, Institute of Gerontology



3015 BSRB
109 Zina Pitcher Place
Ann Arbor, Michigan 48109-2200
Phone: 734/615-0498
FAX: 734/936-9220
E-Mail: davidlom@umich.edu

Research Interests:

Aging is a conserved but poorly understood biological phenomenon. In lower organisms, overexpression or hyperactivity of sirtuins – homologs of the yeast Sir2 deacetylase – confer extended lifespan. Mammals possess seven sirtuins, called SIRT1-SIRT7. Many of these proteins modulate metabolic processes; their potential roles in regulating aging in mammals are uncharacterized. We previously showed that SIRT3 is a mitochondrial factor that deacetylates numerous protein targets in this organelle; we are currently elucidating the biological significance of this activity. More recently we have found that calorie restriction (CR), an intervention that extends lifespan in many organisms, is also associated with perturbations in mitochondrial acetylation. Using a mass spectrometry-based approach, we have identified many factors with altered acetylation during CR as well as numerous novel SIRT3 substrates. We are currently working to uncover how acetylation affects activities of individual factors as well as overall mitochondrial function during CR.

With respect to non-mitochondrial sirtuins, we previously showed that SIRT6 is a nuclear protein that suppresses genomic instability and enhances genotoxin resistance in cells. SIRT6-deficient mice die of a degenerative disorder characterized by profound metabolic abnormalities. We are working to understand the basis for this phenotype through cell culture studies as well as analysis of conditional knockouts and overexpressing mouse models.

In addition to these projects, we are also attempting to isolate novel genes involved in oxidative stress resistance in mammals through shRNA-based screens.


Brief Biography:

Dr. Lombard received a Ph.D. in Biology from Massachusetts Institute of Technology (2000) and an M.D. from Harvard Medical School (2001). He completed residency training in Anatomic Pathology (2001-2003) at Brigham and Women's Hospital in Boston. Following residency training Dr. Lombard joined the laboratory of Professor Frederick Alt at Children's Hospital as a Posdoctoral Fellow. He continued in this role until joining the faculty of the Department of Pathology in September 2008.

Dr. Lombard joined the faculty of the University of Michigan as an Assistant Professor in the Department of Pathology and hold a joint appointment in the Institute of Gerontology as Research Assistant Professor.