Page 109 - NNS 2014 Program & Abstract Book

C2-02
COMBINING ENRICHED ENVIRONMENT AND INDUCED
PLURIPOTENT STEM CELL THERAPY RESTORES FUNC-
TION FOLLOWING TRAUMATIC BRAIN INJURY
Dunkerson, J.D.1 , Young, J.1 , Moritz, K.E.1, Fink, K.2, Dunbar, G.2,
Smith, J.S.1
1Saginaw Valley State University, Saginaw, U.S.
2Field Neuroscience Institute, Saginaw, U.S.
Despite advances towards potential clinically viable therapies there
has been only limited success in improving functional recovery
following traumatic brain injury (TBI). Exposure to an enriched
environment (EE) improves memory, learning, and motor skill de-
velopment. Induced pluripotent stem cells (iPSCs) have been shown
to survive transplantation and influence functional recovery. The
current study evaluated EE/iPSC as a polytherapy for remediating
deficits following medial frontal cortex (mFC) controlled cortical
impact (CCI) injury. Sixty adult male rats received a midline mFC
CCI or sham injury. Following surgery, rats were randomly placed in
either EE or standard environment (SE). Seven days later injured rats
received bilateral transplantation of either 100,000 iPSCs or vehicle.
Behavioral measures included the Open-field, vermicelli handling
(VHT), Morris water maze (MWM), and Rotarod (RR) tasks. Brains
were perfused, extracted, and embedded in paraffin. The brain tissue
was sliced into 30 lm thick sections and labeled with hematoxlyn
and eosin; additionally, 250 lm thick sections were cleared using
SeeDB and labeled with GFAP, MAP2, and NeuN. Open-field data
revealed that injured rats had initially lower activity levels when
compared to shams. However, the long lasting effects of combined
therapies resulted in activity patterns typical of enriched shams. On
the VHT, rats that received EE/iPSC polytherapy performed better
than HBSS-treated rats. Rats exposed to EE or iPSCs performed
equivalently to Sham/EE rats on the MWM. Proficiency on the RR
was consistently better in EE housed groups as compared to their SE
counterparts. Confocal microscopy confirmed that iPSCs survived,
migrated away from the transplantation site, and expressed neural
phenotypic characteristics. Overall, rats that received either EE or iPSC
therapy improved on cognitive and motor tasks, however, full cog-
nitive restoration was seen only with the EE/iPSC polytherapeutic
approach. These data suggest that EE/iPSC therapy should be ex-
plored as a potential, clinically relevant, polytherapy for the treat-
ment of TBI.
Key words
enriched environment, induced pluripotent stem cell, iPSC, poly-
therapy, SeeDB, traumatic brain injury
C2-03
TRAUMATIC BRAIN INJURY REDUCES VASCULAR RE-
ACTIVITY IN AGING RAT MIDDLE CEREBRAL ARTERIES
Zeng, Y.P., Sell, S.L., Prough, D.S., Leavitt, S., Parsley, M., DeWitt,
D.S.
University of Texas Medical Branch, Department of Anesthesiology,
Galveston, USA
Age is a consistent predictor of poor outcome following traumatic
brain injury (TBI) (Mosenthal,et al., 2002; Susman, et al., 2002). The
causes for the adverse effects of age on brain injury remain obscure. In
experimental animals and patients, TBI reduces cerebral vascular
compensatory responses to changes in arterial blood pressure (DeWitt
& Prough, 2003). Aged rats subjected to weight drop TBI exhibited
reduced cerebral-blood-flow (CBF) and significantly reduced hy-
peremia following posttraumatic-hypoperfusion (Biagas, et al.,
1996). Here we test the hypothesis that age reduces the post-trau-
matic vascular reactivity of the middle cerebral artery (MCA). Old
(22–24 months) and young (3–4 months) male rats (n = 16/group)
were anesthetized with isoflurane, intubated, and mechanically
ventilated on 1.5–2.0% isoflurane in a mixture of air and oxygen and
received either moderate fluid percussion or sham injury and were
randomly assigned to one of four groups: aged-sham, a ged-TBI,
young-sham, young-TBI. The rats were monitored for one hour post
injury than decapitated and segments of the MCA were harvested.
The MCA segments were mounted on an arteriograph, pressurized
and the diameters were measured as intraluminal pressure was se-
quentially reduced from 100 to 20 mmHg in 20 mmHg decrements.
MCAs in the young and aged sham groups showed normal, step-wise
increases in diameter with decreases in intraluminal pressure from
100 to 40 mmHg. However there was an effect of age in the sham-
groups at intraluminal pressures of 40 and 20 mmHg (P < 0.05). In
young and aged TBI-groups, the MCA diameter was smaller com-
pared to the sham-groups with each step-wise reduction in intra-
vascular pressure. There was a significant effect of age on
vasodilatory responses in the aged TBI group compared to the
young-TBI group (P < 0.05) with the aged TBI group showing re-
duced vasoresponsiveness. In conclusion, vasodilatory responses to
decreases in intravascular pressure in isolated MCAs were reduced
in both TBI-groups compared to sham. In addition, the aged TBI-
group demonstrated significantly reduced vascular reactivity com-
pared to the young TBI-group, suggesting that reduced vascular
reactivity after TBI may contribute to the worse outcome for older
patients with TBI.
Key words
aging rat, middle cerebral arteries, TBI, vascular reactivity
C2-04
A COMBINATION THERAPY OF PHENYTOIN AND
ETHOSUXIMIDE IMPROVED THERAPEUTIC BENEFITS
AGAINST POST-TRAUMATIC NONCONVULSIVE SEI-
ZURES
Lu, X.M.1, Tallarida, R.2, Mountney, A.1, Cao, Y.1, Liao, Z.1, Schmid,
K.E.1, Shear, D.A.1, Tortella, F.C.1
1Walter Reed Army Institute of Research, Silver Spring, USA
2Temple University, Philadelphia, USA
Previously we reported that treatment with phenytoin (PHT) or
ethosuximide (EXM) dose-dependently attenuated post-traumatic
nonconvulsive seizures (NCS) induced in rats by penetrating bal-
listic-like brain injury (PBBI). The efficacious monotherapy dose
ranges of the two drugs were identified to be 20–30 mg/kg (PHT)
and 125–187.5 mg/kg (EXM), but moderate-severe sedation re-
sulted. In this study isobolographic analysis was used to construct
fixed dose ratios for the combination of PHT and EXM to determine
if combined treatments could improve anti-seizure efficacy. All rats
received frontal PBBI and were immediately subjected to post-
injury EEG/video monitoring for 72 h for seizure detection. PHT
and EXM were tested in pairs at the following fixed dose ratios: 1.8/
5.5, 3.6/11.1, 7.2/22.2, or 14.4/44.4 mg/kg (PHT/EXM) and the
treatments were given intravenously twice/day for three consecutive
days, initiated 30 min post-injury. Control animals received match-
ing vehicle treatments. Outcome measures included NCS incidence,
frequency, duration, and onset latency. The results showed that
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