title: The Effect of Underwater Blast on Aggregating Brain Cell Cultures.
abstract: Although the deleterious effects of primary blast on gas-filled organs are well accepted, the effect of blast-induced shock waves on the brain is less clear because of factors that complicate the interpretation of clinical and experimental data. Brain cell aggregate cultures are comprised of multiple differentiated brain cell types and were used to examine the effects of underwater blast. Suspensions of these cultures encased in dialysis tubing were exposed to explosive-generated underwater blasts of low (∼300 kPa), medium (∼2,700 kPa), or high (∼14,000 kPa) intensities and harvested at 1-28 days post-exposure. No changes in gross morphology were noted immediately or weeks after blast wave exposure, and no increases in either apoptotic (caspase-3) or necrotic (lactate dehydrogenase) cell death were observed. Changes in neuronal (neurofilament H, acetylcholinesterase, and choline acetyltransferase) and glial (glial fibrillary acidic protein, glutamine synthetase) endpoints did not occur. However, significant time- and pressure-related increases in Akt (protein kinase B) phosphorylation were noted, as well as declines in vascular endothelial growth factor levels, implicating pathways involved in cellular survival mechanisms. The free-floating nature of the aggregates during blast wave exposure, coupled with their highly hydrolyzed dialysis tubing containment, results in minimized boundary effects, thus enabling accurate assessment of brain cell response to a simplified shock-induced stress wave. This work shows that, at its simplest, blast-induced shock waves produce subtle changes in brain tissue. This study has mechanistic implications for the study of primary blast-induced traumatic brain injury and supports the thesis that underwater blast may cause subtle changes in the brains of submerged individuals.
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Sawyer
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Julian J
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Mercy
authors.initials: M
authors.lastname: Villanueva
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Yushan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Peggy
authors.initials: P
authors.lastname: Nelson
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Song
authors.affiliation: 2 Canada West Biosciences , Calgary, Alberta, Canada .
authors.forename: Chengyang
authors.initials: C
authors.lastname: Fan
authors.affiliation: 3 Hyland Quality Systems , Medicine Hat, Alberta, Canada .
authors.forename: Julia
authors.initials: J
authors.lastname: Barnes
authors.affiliation: 1 Defence Research and Development Canada, Suffield Research Center , Medicine Hat, Alberta, Canada .
authors.forename: Lori
authors.initials: L
authors.lastname: McLaws
mesh_terms: D000818:Animals; D001753:Blast Injuries / Q000473:pathology*; D001921:Brain / Q000473:pathology* / Q000502:physiology; D016923:Cell Death / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D002478:Cells, Cultured; D005107:Explosions; D005260:Female; D011247:Pregnancy; D011312:Pressure / Q000009:adverse effects; D051381:Rats; D017207:Rats, Sprague-Dawley
keywords: Akt (protein kinase B); blast-induced brain injury; primary blast; traumatic brain injury (TBI); underwater blast; vascular epidermal growth factor (VEGF)