The focus of the Muscle Energetics Laboratory, led by Dr. Brian Glancy, is to determine how mitochondria are optimized within muscle cells to help maintain energy homeostasis during the large change in energy demand caused by muscle contraction.
Skeletal muscle is the most abundant tissue in humans and faces near instantaneous changes in demand for force production lasting from seconds to minutes to hours. Initiating and maintaining muscle contraction requires rapid, coordinated movement of signals and material within and among various structures located throughout the relatively large muscle cell. The Muscle Energetics Laboratory focuses on the energy distribution aspect of continued muscle contraction, deficits in which have been implicated in many pathologies including diabetes and muscular dystrophy as well as aging. In particular, we aim to determine how mitochondria are optimized as part of the integrated muscle cell to maintain energy homeostasis during the large change in energy demand caused by the onset of muscle contraction. The working hypothesis in the lab is that mitochondrial function within a muscle cell is dictated not only by the amount and composition of mitochondria but also by spatial relationships between mitochondria and the sites of energy storage, utilization, and signaling. Ongoing efforts are centered around the structure, function, composition, and developmental regulation of mitochondrial networks with the goal of gaining better control of and understanding the functional consequences of altering spatial relationships within the muscle energy distribution system.
Electron microscopy image of a mitochondrion with a donut hole (cyan) as well as sarcoplasmic reticulum (magenta), transverse tubules (orange), and contractile A-bands (green), I-bands (red), and Z-disks (blue) from a mouse glycolytic skeletal muscle.
3D rendering of the interior of a mouse skeletal muscle mitochondrion. Mitochondrial outer membrane (red) and inner membrane cristae (green) are shown.
3D rendering of mitochondria (various colors) and the sarcotubular network (green) in an oxidative mouse skeletal muscle.
3D rendering of red blood cells (various colors) within a skeletal muscle capillary of a newborn mouse. The vesicles (upper), mitochondria (middle), and endoplasmic reticulum (lower) within each cell are shown.
3D rendering of four different types of mitochondrial networks in the adult muscles of the fruit fly, Drosophila melanogaster. Leg muscle (upper left), jump muscle (upper right), direct flight muscle (bottom right), and indirect flight muscle (bottom left) mitochondrial networks are shown.
Brian Glancy graduated with a B.A. in Sport Science from the University of the Pacific prior to receiving a Master’s degree in Kinesiology and a Ph.D. in Exercise Science from Arizona State University working with Wayne Willis. He was a postdoctoral fellow with Robert Balaban at the National Heart, Lung, and Blood Institute from 2009 to 2016. Dr. Glancy became an Earl Stadtman Investigator at the NIH with a dual appointment between NHLBI and NIAMS in 2016. He is a member of the American College of Sports Medicine and the American Physiological Society.