title: Characterization of Subcellular Responses Induced by Exposure of Microbubbles to Astrocytes.
abstract: Blast traumatic brain injury (bTBI) has now been identified to associate with adverse health consequences among combat veterans. Post-traumatic stress disorder linked with explosive blasts, for example, may result from such brain injury. The fundamental questions about the nature, diagnosis, and long-term consequences of bTBI and causative relationship to post-traumatic stress disorder remain elusive, however. A better understanding of brain tissue injury requires elucidation of potential mechanisms. One such mechanism may be generation of microcavitation bubbles in the brain after an explosive blast and their subsequent interaction with brain cells. Using a controlled electrical discharge system, we have successfully generated shock waves (∼10 MPa) and microbubbles (20-30 μm) in the cell culture of mouse astrocytes. Detachment of astrocytes from the substrate after exposure to microbubbles was observed, and it depended on repetitive exposures. Of the cells that survived the initial assault, several subcellular changes were monitored and determined using fluorescent microscopy, including cell viability, cytoskeletal reorganization, changes in focal adhesion, membrane permeability, and potential onset of apoptosis. While the astrocytes impacted by the shock wave only demonstrated essentially unaltered cellular behavior, the astrocytes exposed to microbubbles exhibited significantly different responses, including production of reactive oxygen species by collapse of microbubbles. In the present study, we characterized and report for the first time the altered biophysical and subcellular properties in astrocytes in response to exposure to the combination of shock waves and microbubbles.
authors.affiliation: 1 Department of Bioengineering, University of Illinois at Chicago , Chicago, Illinois.
authors.forename: Shan
authors.initials: S
authors.lastname: Sun
authors.affiliation: 1 Department of Bioengineering, University of Illinois at Chicago , Chicago, Illinois.
authors.forename: Johnwesly
authors.initials: J
authors.lastname: Kanagaraj
authors.affiliation: 2 Department of Kinesiology and Community Health, University of Illinois at Urbana-Champaign , Urbana, Illinois.
authors.forename: Lindsey
authors.initials: L
authors.lastname: Cho
authors.affiliation: 3 Department of Electrical and Computer Engineering, Old Dominion University , Norfolk, Virginia.
authors.forename: Dongkoo
authors.initials: D
authors.lastname: Kang
authors.affiliation: 3 Department of Electrical and Computer Engineering, Old Dominion University , Norfolk, Virginia.
authors.forename: Shu
authors.initials: S
authors.lastname: Xiao
authors.affiliation: 1 Department of Bioengineering, University of Illinois at Chicago , Chicago, Illinois.
authors.forename: Michael
authors.initials: M
authors.lastname: Cho
mesh_terms: D000818:Animals; D001253:Astrocytes / Q000473:pathology*; D001696:Biomechanical Phenomena; D001753:Blast Injuries / Q000473:pathology*; D001930:Brain Injuries / Q000473:pathology*; D020169:Caspases / Q000378:metabolism; D002448:Cell Adhesion; D002470:Cell Survival; D002478:Cells, Cultured; D051379:Mice; D045423:Microbubbles / Q000009:adverse effects*; D018625:Microscopy, Atomic Force; D017382:Reactive Oxygen Species / Q000378:metabolism; D013347:Subcellular Fractions / Q000473:pathology*; D013481:Superoxides / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D013481:Superoxides; D020169:Caspases
keywords: astrocytes; atomic force microscope; fluorescent microscopy; microbubbles; principle of symmetry; shock waves