Page 152 - NNS 2014 Program & Abstract Book

the movement of the tip for the first 15ms, then, the velocity of the tip
was essentially identical regardless of velocity setting. The terminal
location of the tip when it is stationary during final extension was near
the desired depth for most of the impact time. The analysis suggests
that velocity setting plays little, if any, role as a variable in CCI injury.
Depth settings were reproducible and closely matched stereotaxic
settings, suggesting this variable (as well as tip diameter and shape;
not studied here) may be the significant factors in validation of CCI
models. Results indicate CCI devices should be characterized to meet
future ‘‘methods-reporting’’ standards.
Key words
calibration, controlled cortical impact, methods reporting
D2-20
DEVELOPMENT AND VALIDATION OF TWO ZEBRAFISH
MODELS OF TBI
McCutcheon, V.1, Park, E.2, Liu, E.2 , Tavakkoli, J.3 , SobheBidari, P.3,
Baker, A.J.4
1University of Toronto, Institute of Medical Sciences, Toronto,
Canada
2Keenan Research Centre in the Li Ka Shing Knowledge Institute at
St. Michael’s Hospital, Toronto, Canada
3Ryerson University, Department of Physics, Toronto, Canada
4University of Toronto, Departments of Anesthesia & Surgery, Tor-
onto, Canada
Traumatic brain injury (TBI) is a leading cause of death and mor-
bidity in industrialized countries with considerable associated direct
and indirect healthcare costs. The cost and time associated with
preclinical development of TBI therapeutics is lengthy and expen-
sive. The Zebrafish (ZF) is an emerging model organism for studies
of disease and development owing to its similarity in genome and
cell signalling pathways in mammalian species, ease of genome
manipulation, capacity for whole animal in vivo imaging, rapid rate
of procreation, and amenability to large scale automated preclinical
drug validation. We have developed a two-stage model of TBI in
ZF using larvae and adult fish. In larval ZF, we developed a high-
throughput method of screening therapeutic compounds in a chemi-
cally-induced brain injury model. As proof-of-concept, we demonstrate
dose-dependent larval survival with known neuroprotective com-
pounds (eg. MK-801). We are currently validating other known
neuroprotective compounds in the larvae ZF model. Compound li-
braries of FDA-approved drugs are currently being screened for re-
purposing in our larval model. Candidate compounds will be further
evaluated in an adult ZF model. We use a targeted 1-MHz pulsed high
intensity focused ultrasound (pHIFU) system applied to adult ZF to
produce a non-penetrating injury to the brain. Preliminary results
indicate that pHIFU pressure amplitude at 10MPa results in a
70.5 – 1% and 102 – 1% change in NF160 expression at 5,000 and
10,000 cycles respectively. b-III tubulin shows a 14 – 1% and
16 – 1% increase at the same parameters. We also found a 30 – 1%
increase in cleaved caspase-3 expression in injured brains compared
to controls. The adult ZF injury model allows whole animal be-
haviour outcome measures such as post-injury recovery times which
demonstrate a dose dependent effect with increasing injury severity.
Adult ZF subject to pHIFU also show locomotor swim deficits at
24 h post injury. Our preliminary results indicate that the ZF exhibits
similar responses to injury and pharmacotherapeutic manipulation as
found in mammalian pathophysiology after TBI. This suggests the
possibility of using a two-step ZF injury model system to screen
compound libraries to quickly identify potential therapeutic candi-
dates at a fraction of the time and cost of studies in mammalian
species.
Key words
drug screening, zebrafish
D2-21
COMPARISON OF TBI MODELS USING BRAIN DAMAGE
MARKERS, AND HISTOLOGICAL AND BEHAVIORAL
OUTCOMES IN OPERATION BRAIN TRAUMA THERAPY
Mondello, S.1 , Shear, D.A.2, Bramlett, H.M.3, Dixon, C.E.4, Schmid,
K.2, Dietrich, W.D.3, Wang, K.K.5, Hayes, R.L.6, Tortella, F.C.2,
Kochanek, P.M.4
1University of Messina, Messina, Italy
2Walter Reed Army Institute of Research, Silver Spring, USA
3University of Miami Miller School of Medicine, Miami, USA
4University of Pittsburgh, Pittsburgh, USA
5University of Florida, Gainesville, USA
6Banyan Biomarkers, Alachua, USA
Successful preclinical testing of neuroprotective drugs depends on the
selection and characterization of appropriate animal models. Opera-
tion Brain Trauma Therapy (OBTT) is a multi-center pre-clinical drug
screening consortium testing promising therapies for traumatic brain
injury (TBI) in 3 well-established animal models (parasagittal fluid
percussion injury [FPI], controlled cortical impact [CCI] and pene-
trating ballistic-like brain injury [PBBI]). Here, we characterize/
compare these models using circulating glial (glial fibrillary acidic
protein [GFAP]) and neuronal (ubiquitin C-terminal hydrolase [UCH-
L1]) markers, behavior, and histology.
At 4 h post-injury UCH-L1 was higher in CCI vs. FPI and PBBI
(P < 0.001) and GFAP lower in PBBI vs. CCI and FPI (P < 0.001).
Differences were also found comparing shams across models, with
higher UCH-L1 levels in CCI vs. FPI and PBBI (P < 0.001) and lower
GFAP levels in FPI vs. CCI and PBBI (P < 0.001 and P <0.01, re-
spectively). Increased cognitive deficits were observed in PBBI and CCI
in the hidden platform task vs. FPI (P < 0.001) and in sham-CCI vs.
sham-PBBI and sham-FPI (P < 0.001). Lesion volume was larger in
PBBI vs. FPI and CCI (P < 0.001), while hemispheric volume loss was
smaller in FPI vs. CCI and PBBI (P < 0.001). Average latency to find
the hidden platform correlated with GFAP concentrations across mod-
els, but not with UCH-L1. Also, GFAP but not UCH-L1 correlated with
lesion volume and hemispheric volume loss across models (P < 0.001).
Experimental TBI models display major differences in biomarker
profiles and functional and pathological consequences. Circulating
GFAP levels best reflected behavioral and histological outcomes. Our
data provide a unique characterization of TBI models that enlighten
our understanding of the relationship between biomarkers and tradi-
tional TBI outcomes and could advance translational research. Sup-
port: US Army W81XWH-10-1-0623
Key words
animal model, OBTT, traumatic brain injury
D2-22
CHARACTERIZATION OF A LABORATORY-BASED RO-
DENT ROTATIONAL ACCELERATION TBI DEVICE
Poeske, M.1–3, Chmill, R.1–3, Kollman, A.1–3, Haas, M.1–3, Shah, A.1–3,
Imas, O.1, Stemper, B.D.1–3
A-120