AIMRC Seminar: Non-Invasive Metabolic Imaging for Single Cells and Embryo Development

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Michelle Digman, associate professor of biomedical engineering at the University of California, Irvine.

The Arkansas Integrative Metabolic Research Center will host Michelle Digman, associate professor of biomedical engineering at the University of California, Irvine, at 12:55 p.m. Wednesday, May 3, in ENGR 209, when Digman will present her work on non-invasive metabolic imaging for single cells and embryo development.  

Nicotinamide adenine dinucleotide (NAD) and its reduced form, NADH, play a central role in bioenergetics as an enzymatic cofactor and reducing equivalent in cellular metabolic and redox reactions. The NADH/NAD+ ratio has significant impact on energy production, cell survival, proliferation, longevity and aging. Lifetime measurements of free/bound NADH autofluorescence has been demonstrated to approximate the NADH/NAD+ ratio and has been established as a reliable means for estimating the mode of metabolism used by cells and tissues. We use the phasor-FLIM (Fluorescence Lifetime Imaging Microscopy) approach to spatially map NADH in both free and bound form in living cells and tissues. The phasor approach graphically depicts the change in lifetime at a pixel level without the requirement for fitting the decay. Each fluorescent species has a location in the phasor plot that allows identification and quantitative mapping of tissue components without exogenous labeling. We identify collagen, retinol, retinoic acid, flavins, nicotinamide adenine dinucleotide and porphyrin by their phasor signature and we map their relative concentration within the tissue. The phasor method to FLIM is a non-invasive tool that characterizes local microenvironment and monitor differentiation and diseases in label-free living tissues. We also apply the phasor-FLIM to capture endogenous fluorescent biomarkers of preimplantation embryos as a non-morphological and non-invasive caliber for embryo quality.  

Digman was awarded a doctorate degree in chemistry with specialization in biochemistry from the University of Illinois at Chicago in 2003.  She did her postdoctoral work in the Department of Physics at the University of Illinois at Urbana-Champaign in biophysics until this lab moved to the University of California Irvine. She became Optical Bio-Core director until she joined the biomedical engineering department in 2013.

Digman is currently the associate chair for graduate affairs and holds a joint appointment in the Department of Developmental and Cell Biology. Her research lab is focused on developing novel biophysical and optical tools to study biological questions with the goal of applying the gained knowledge to the advancement of human medicine. Digman is AIMBE Fellow, Scialog Fellow, Allen Distinguished Investigator in Immunometabolism, and has won several awards including the NSF-CAREER award, the Hellman Fellowship, the Fluorescence Young Investigator Award from the Biophysical Society, the Faculty Innovation in Teaching award and has received the Henry Samueli Career Development Chair.  

This seminar is also available via Zoom.  

Pizza and beverages will be served in ENGR 209.   

This event is supported by the NIGMS of the National Institutes of Health under Award Number P20GM139768. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.