Shawn E. Bearden, Ph.D.
- Associate Professor of Physiology
- Director, ISU Biomedical Research Institute
- Head, Advanced Imaging Core Facility
- bearshaw@isu.edu
- (208) 282-6269
- Gale Life Sciences Bldg, Rm 329
Vascular Health Laboratory
Microcirculation, aging, sex, gender, exercise, cardiovascular physiology, neurovascular interactions, blood flow control
Education
- B.S. Sports Medicine, 1994, University of Virginia, Charlottesville, VA
- M.S. Exercise Science & Health Promotion, 1996, George Mason University, Fairfax, VA
- Ph.D. Exercise Physiology, 2000, Florida State University, Tallahassee, FL
- Postdoc, Microcirculation, 2004 Yale University School of Medicine and the John B. Pierce Laboratories, New Haven CT
Biographical Sketch
We study the structure and function of microvascular networks with a focus on the cells that line blood vessels and form capillaries, endothelial cells. Our primary interests lie at the junctions between these cells. Junctions between endothelial cells are essential for cell-cell communication (gap junctions) and to regulate vascular permeability (tight and adherens junctions). Normal function of these junctions allows proper nutrient delivery and distribution within organs such as skeletal muscle, heart, and brain while regulating what substances may pass between the blood and tissues. We use confocal and multiphoton microscopy to study the structure and function of microvascular junctions with an emphasis on cerebral vessels. These in vivo approaches are complemented by techniques in molecular biology, pharmacology, and immunohistochemistry to better understand the mechanisms of cell-cell coordination in normal and disease states. Our ongoing purpose is to identify modifiable mechanisms that may be exploited to reduce the morbidity and mortality associated with vascular dysfunction. Our work is funded by the National Institutes of Health.
Teaching
- BIOL 301/302 Anatomy & Physiology
- BIOL 499/652 Advanced Topics in Physiology
SELECTED PEER-REVIEWED PUBLICATIONS
(underline denotes undergraduate student, italics denotes graduate student)
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Beard RS, Reynolds JJ, Bearden SE. Metabotropic glutamate receptor 5 mediates phosphorylation of vascular endothelial cadherin and nuclear localization of β-catenin in response to homocysteine. Vascular Pharmacology, 56(3-4):159-167, 2012. PMID: 22285407
- First demonstration of ionotropic-metabotropic glutamate receptor signaling in endothelium
- Chen CH, Beard RS, Bearden SE. Homocysteine impairs endothelial cell proliferation by activating metabotropic glutamate receptor 5. Microcirculation, EPub Jan 5, 2012 PMID: 22221504
- Mayo JN, Beard RS, Price TO, Chen CH, Erickson MA, Ercal N, Banks WA, Bearden SE. Nitrative Stress in Cerebral Endothelium is Mediated by mGluR5 in Hyperhomocysteinemia. Journal of Cerebral Blood Flow and Metabolism, 32(5):825-834, 2012. PMID: 22186670
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Beard RS, Reynolds JJ, Bearden SE. Hyperhomocysteinemia Increases Permeability Of The Blood-Brain Barrier By NMDA Receptor-Dependent Regulation Of Adherens And Tight Junctions. Blood, 118(7):2007-2014, 2011. PMID: 21705496
- First in vivo rescue of the elevated BBB permeability caused by mild hyperhomocysteinemia
- Beard RS, Bearden SE. Vascular Complications of Cystathionine ?-Synthase Deficiency. American Journal of Physiology: Heart and Circulatory Physiology, 300(1):H13-H26, 2011. review article. PMID: 20971760
- Bearden SE, Beard RS, Pfau JC. Extracellular transsulfuration generates hydrogen sulfide from homocysteine and protects endothelium from redox stress. American Journal of Physiology: Heart and Circulatory Physiology, 299:H1568-H1576, 2010. PMID: 20817827
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Moore AW, SE Bearden, and SS Segal. Regional activation of rapid onset vasodilatation in mouse skeletal muscle: Regulation through ?-adrenoreceptors. Journal of Physiology, 588(17):3321-3331, 2010. PMID: 20624796
- Selected for editorial comment/review
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Olson, K., N. Whitfield, S.E. Bearden, J. St. Letger, E. Nilson, Y. Gao, J. Madden. Hypoxic pulmonary vasodilation: A paradigm shift with a hydrogen sulfide mechanism. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 298:R51-R60, 2010. PMID: 19889863
- First demonstration of hydrogen sulfide as a mediator of pulmonary vasodilation and peripheral vessel vasoconstriction, mimicking the effects of hypoxia
- Cheuvront S.N., S.E.Bearden, R.W. Kenefick, B.R. Ely, D.W. Degroot, M.N. Sawka, S.J. Montain. A simple and valid method to determine thermoregulatory sweating threshold and sensitivity. Journal of Applied Physiology, 107(1):69-75, 2009. PMID: 19423839
- Looft-Wilson, R.C., B.S. Ashley, J.E. Billig, M.R. Wolfert, L.A. Ambrecht, and S.E. Bearden. Chronic diet-induced hyperhomocysteinemia impairs eNOS regulation in mouse mesenteric arteries. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 295(1), R59-R66, 2008. PMID: 18448615
- Bearden S.E., E. Linn, B.S. Ashley, R.C. Looft-Wilson. Age-related changes in conducted vasodilation: effects of exercise training and role in functional hyperemia. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 293(4), R1717-R1721, 2007. PMID: 17652355
- Bearden, S.E. Advancing age produces sex differences in vasomotor kinetics during and after skeletal muscle contraction. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, 293(3):R1274-R1279, 2007. PMID: 17626125
- Bearden, S.E. Effect of aging on the structure and function of skeletal muscle microvascular networks. Microcirculation, 13(4): 305-314, 2006. review article. PMID: 16611595
- Payne, G.W., Bearden, S.E. The microcirculation of skeletal muscle in aging. Microcirculation, 13(4): 275-277, 2006. review article. PMID: 16611593
- Bearden, S.E., S.S. Segal. Neurovascular alignment in adult mouse skeletal muscles. Microcirculation, 12(2):161-167, 2005. PMID: 15824038
- Bearden, S.E., G.W. Payne, A. Chisty, S.S. Segal. Arteriolar network architecture and vasomotor function with aging in mouse gluteus maximus muscle. Journal of Physiology, 561(Pt 2):535-545, 2004. PMID: 15388783
- Bearden, S.E., S.S. Segal. Microvessels promote motor nerve survival and regeneration through VEGF following ectopic reattachment. Microcirculation, 11(8):633-644, 2004. PMID: 15726813