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1

University of Messina, Neurosciences, Messina, Italy

2

UP, CCM, Pittsburgh, USA

3

WRAIR, Neuroprotection, Silver Spring, USA

4

UM, Neurological Surgery, Miami, USA

5

UF, Psychiatry & Neuroscience, Gainesville, USA

6

Banyan Biomarkers, Biomarkers, Alachua, USA

Levetiracetam (LEV) is a new anti-epileptic used for prevention of post-

traumatic epilepsy that has been shown to be neuroprotective and im-

prove outcomes after TBI even in the absence of seizure activity. The

present work, part of the Operation Brain Trauma Therapy (OBTT) a

multi-center pre-clinical drug screening consortium, investigated the

effects of early, single-dose LEV treatment on behavioral and histo-

pathological outcomes and TBI biomarkers across multiple models.

Adult rats subjected to controlled cortical impact (CCI), fluid per-

cussion (FPI), or penetrating ballistic-like brain injury (PBBI) re-

ceived a single 15 min post-injury IV dose of LEV (54 or 170 mg/kg)

or vehicle. Circulating concentrations of glial fibrillary acidic protein

(GFAP) and ubiquitin C-terminal hydrolase (UCH-L1) were measured

by ELISA at 4 and 24h after-injury.

In CCI, LEV 170 mg/kg was able to markedly improve motor

functions and reduces hemispheric tissue loss (

p

<

0.05 vs vehicle).

These effects were accompanied by a significant reduction in GFAP

concentration at 24h (p

<

0.05 vs vehicle). A positive, albeit modest,

effect on motor and cognitive functions was noted in animals treated

with LEV 54 mg/kg. In FPI, LEV at both doses trended towards im-

proved cognitive outcomes in several behavioral paradigms, but with

no effect on biomarker levels. In PBBI, there was no motor or cog-

nitive benefit from either dose and no benefit on histology. In the LEV

54 mg/kg group, GFAP levels returned to sham levels at 24h after-

injury. LEV had no effect on UCH-L1 concentrations.

Our results suggest a potential application of early, single-dose

Levetiracetam as a neuroprotective therapy for specific types of TBI.

Furthermore, GFAP can be used to identify and monitor drug effect

and might be a valuable theragnostic marker. Support:US Army

W81XWH-10-1-0623.

Keywords: Glial fibrillary acidic protein, Ubiquitin carboxyl-ter-

minal hydrolase-L1, Fluid percussion injury, Controlled cortical im-

pact, Penetrating ballistic-like brain injury, Rat

D8-17

EVALUATION OF GLIBENCLAMIDE IN THE MIAMI FLUID

PERCUSSION MODEL OF TRAUMATIC BRAIN INJURY: AN

OBTT CONSORTIUM STUDY

Helen Bramlett

1,2

, Ofelia Furones-Alonso

2

, Juliana Sanchez-Molano

2

,

David Sequiera

2

, William Moreno

2

,

W. Dalton Dietrich

1,2

1

University of Miami Miller School of Medicine, Neurological Sur-

gery, Miami, USA

2

University of Miami Miller School of Medicine, Miami Project to

Cure Paralysis, Miami, USA

Glibenclamide (GLI) is a sulfonylurea receptor (SUR1) regulated NC

Ca-

ATP

channel antagonist that has shown promise in preclinical traumatic

brain injury (TBI) studies. Male Sprague-Dawley rats were anesthetized

and underwent moderate fluid percussion (FPI; 1.8–2.1 atm) TBI. Rats

were randomized into three groups and administered GLI (10

l

g/kg IP)

or vehicle 10min post-TBI followed by SQ Alzet mini pump implan-

tation (1.0

l

l/h) for drug or vehicle administration. The pump was re-

moved between 168 and 172 hrs post-injury. Animal groups were TBI-

GLI (n

=

15), TBI-Veh (n

=

15) or Sham (n

=

15). Rats were tested on

day 7 post-injury for sensorimotor function (gridwalk, cylinder task).

On days 13–21, rats were assessed for cognitive function utilizing the

simple place task, probe trial and working memory task. On day 21,

brain tissue was processed for histology. One-way ANOVA was sig-

nificant for the cylinder task (p

<

0.05) but not for the gridwalk. TBI-

GLI animals were significantly improved compared to TBI-Veh

(p

<

0.05). For the hidden platform task, two-way repeated measures

ANOVA for latency was not significant for group x day. TBI GLI

treated animals treated groups exhibited similar latencies to TBI-Veh.

Repeated measures ANOVA for working memory latency was signifi-

cant for trial (p

<

0.001), but not group or group x trial. Lesion volume

or cortical volume loss was not significant between the TBI groups. We

conclude that sustained treatment with GLI after FP produced a mild

motor benefit but did not improve cognitive function or decrease his-

tological damage. Although this drug does target several patho-

mechanisms including edema and necrosis, the current study reports

only motor benefit for GLI treatment in the rat FPI model. Our be-

havioral findings mirror the motor benefit seen in CCI, although lack of

cognitive benefit dampens enthusiasm. Support: US Army W81XWH-

10-1-0623.

Keywords: Glibenclamide, OBTT, fluid percussion

D8-18

EVALUATION OF GLIBENCLAMIDE IN THE PITTSBURGH

CONTROLLED CORTICAL IMPACT MODEL OF TRAU-

MATIC BRAIN INJURY: AN OBTT CONSORTIUM STUDY

Ruchira Jha

1,4

, Hong Yan

2,4

, C. Edward Dixon

2,4

, Samuel Poloyac

3,4

,

Travis Jackson

1,4

, Keito Hoshitsuki

3

, Xiecheng Ma

2,4

, Jeremy

Henchir

2,4

, Keri Feldman

1,4

, Patrick Kochanek

1,4

1

Univ of Pittsburgh, Critical Care, Pittsburgh, USA

2

Univ of Pittsburgh, Neurosurgery, Pittsburgh, USA

3

Univ of Pittsburgh, Pharmacy, Pittsburgh, USA

4

Safar Center, Critical Care, Pittsburgh, USA

Preclinical studies suggest that Glibenclamide (GLI) improve out-

comes in TBI through decreasing cerebral edema. GLI (FDA ap-

proved) inhibits the sulfonylurea receptor SUR1. SUR1 also

associates with Trpm4 and mediates cerebral edema via water influx.

Thus, Operation Brain Trauma Therapy (OBTT) selected GLI for

evaluation. In Pittsburgh we studied the effect of GLI on motor,

cognitive and neuropathological outcomes in CCI. Adult, male,

Sprague-Dawley rats were divided into 3 groups (n

=

10/group): sham,

CCI

+

vehicle, CCI

+

GLI. Anesthetized rats underwent CCI vs sham.

An intraperitoneal loading dose (10

l

g/kg) was given 10 min post

injury, followed by a 7-d subcutaneous-infusion at 0.2

l

g/h. Beam

balance (BB) and walking (BW) were assessed at d1-5. Cognitive

outcomes were assessed using Morris Water Maze (MWM, 14-20d).

Contusion volume and hemispheric tissue loss were assessed on d21.

Studies in sham rats estimated that average peak (1h) and steady state

concentrations (24h) post-loading dose were 5.4

1.4 and 1.2

0.3 ng/

mL, respectively (n

=

5). There was benefit on BB and BW in GLI vs

vehicle (p

<

0.05) resulting in full points for treatment for both tasks.

Cognitive outcome did not differ between GLI and vehicle groups,

and in fact, an intermediate detrimental effect was seen on MWM

performance with GLI treatment. Consistent with the motor effect,

GLI reduced lesion volume vs vehicle (p

<

0.05). We conclude, GLI

improved motor and histological outcomes after CCI in rats within the

rigors of OBTT. GLI is the only drug thus far tested in OBTT to

reduce contusion volume in CCI, but lack of cognitive benefit is

disappointing. Given that it targets brain edema, its effects in CCI may

be underestimated by the craniectomy. Further studies are warranted

in contusion. Support:USArmyW81XWH-10-1-0623

A-119