This work was supported by National Institutes of Health grant, R01 AG033620 (BG) and by Robert Draper Technology Innovation Funding (DAW).

1. Construction of the HIT Device&#160;
<ol>
	<li>Attach the spring to the board using two clamps and four screws (Figure 1A). Center the clamps relative to the width of the board and butt them up against one another with the outer clamp flush with the edge of the board. Prior to attaching the clamps, bend them using pliers to fit tightly over the spring. 
	NOTE: See Table 1 for descriptions of the materials required for constructing the HIT device.&#160;The clamped end of the spr...

<ol>
	<li>Harrison-Felix, C. L., Whiteneck, G. G., Jha, A., DeVivo, M. J., Hammond, F. M., Hart, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mortality+over+four+decades+after+traumatic+brain+injury+rehabilitation:+A+retrospective+cohort+study.">Mortality over four decades after traumatic brain injury rehabilitation: A retrospective cohort study.</a> Arch Phys Med Rehabil. 90, 1506-1513 (2009).</li><li>Coronado, V. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surveillance+for+traumatic+brain+injury-related+deaths+&#8211;+United+States.">Surveillance for traumatic brain injury-related deaths &#8211; United States.</a> MMWR Surveill Summ. 60, 1-32 (1997).</li><li>Masel, B., DeWitt, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Traumatic+brain+injury:+A+disease+process,+not+an+event.">Traumatic brain injury: A disease process, not an event.</a> J. Neurotrauma. 27, 1529-1540 (2010).</li><li>Blennow, K., Hardy, J., Zetterberg, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+neuropathology+and+neurobiology+of+traumatic+brain+injury.">The neuropathology and neurobiology of traumatic brain injury.</a> Neuron. 76, 886-899 (2012).</li><li>Prins, M., Greco, T., Alexander, D., Giza, C. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+pathophysiology+of+traumatic+brain+injury+at+a+glance.">The pathophysiology of traumatic brain injury at a glance.</a> Disease Models Mech. 6, 1307-1315 (2013).</li><li>Menon, D. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Unique+challenges+in+clinical+trails+in+traumatic+brain+injury.">Unique challenges in clinical trails in traumatic brain injury.</a> Crit Care Med. 37, S129-S135 (2009).</li><li>Xiong, Y., Mahmood, A., Chopp, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Animal+models+of+traumatic+brain+injury.">Animal models of traumatic brain injury.</a> Nature Rev Neurosci. 14, 128-142 (2013).</li><li>Balsiger, Z., Leudkte, J., Mawer, S., Willey, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> HIT device high speed analysis. , (2014).</li><li>Davceva, N., Janevska, V., Illevski, B., Petrushevska, G., Popeska, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+occurrence+of+acute+subdural+haematoma+and+diffuse+axonal+injury+as+two+typical+acceleration+injuries.">The occurrence of acute subdural haematoma and diffuse axonal injury as two typical acceleration injuries.</a> J Forensic Leg Med. 19, 480-484 (2012).</li><li>Katzenberger, R. J., Loewen, C. A., Wassarman, D. R., Petersen, A. J., Ganetzky, B., Wassarman , D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Drosophila.+model+of+closed+head+traumatic+brain+injury.">A Drosophila. model of closed head traumatic brain injury.</a> Proc Natl Acad Sci USA. 110, E4152-E4159 (2013).</li><li>Fang, Y., Bonini, N. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Axon+degeneration+and+regeneration:+insights+from+Drosophila+.models+of+nerve+injury.">Axon degeneration and regeneration: insights from Drosophila .models of nerve injury.</a> Annu Rev Cell Biol. 28, 575-597 (2012).</li><li>Babcock, D. T., Ganetzky, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+method+for+accurate+and+rapid+measurement+of+flight+performance+in+Drosophila.">An improved method for accurate and rapid measurement of flight performance in Drosophila.</a> J Vis Exp. (84), e51223 (2014).</li><li>Tully, T., Preat, T., Boynton, S. C., Vecchio, M. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetic+dissection+of+consolidated+memory+in+Drosophila.">Genetic dissection of consolidated memory in Drosophila.</a> Cell. 79, 35-47 (1994).</li><li>Andretic, R., Shaw, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Essentials+of+sleep+recordings+in+Drosophila.:+moving+beyond+sleep+time.">Essentials of sleep recordings in Drosophila.: moving beyond sleep time.</a> Methods Enzymol. 393, 759-772 (2005).</li></ol>

We have no conflicts of interest to disclose.

The HIT device method is distinguished from other methods that inflict traumatic injury in flies&#160;by the fact that it causes closed head rather than penetrating TBI11. Furthermore, the HIT device method takes less time, effort, and skill to inflict TBI in many flies, so the method is more amenable than other methods to large-scale genetic screens. Lastly, the fact that primary injuries inflicted by the HIT device are not limited to the brain is both a limitation and an advantage. It is a limitation because...

An author's name was corrected in the publication of <a href="http://www.jove.com/video/52905">A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila</a>. The second to last author's was spelled incorrectly. It has been updated from:
Barry Ganetky
to:
Barry Ganetzky

An author's name was corrected in the publication of <a href="http://www.jove.com/video/52905">A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila</a>.

Erratum: A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Traumatic brain injury (TBI) is defined as injury to the brain from an external mechanical force. Most commonly, TBI results from closed head forces such as blunt forces and inertial acceleration and deceleration forces that cause the brain to strike the inside of the skull. In the United States, it is estimated that 50,000 individuals die each year from TBI and 2.5-6.5 million individuals are living with the consequences of TBI, including debilitating physical, cognitive, and behavioral problems1,2. The consequences of TBI are not only due to primary mechanical injuries to the brain but also to secondary cellular and molecular injuries to the brain as well as other tissues that occur over time3-5. The development of approaches to diagnose and treat TBI has proven to be difficult because TBI is a complex disease process. The variable nature of primary injuries, human physiology, and environmental factors results in heterogeneous secondary injuries and pathologies. Underlying variable factors include the severity of the primary injury, the time between repetitive primary injuries, and the age and genotype of the individual. Understanding how each variable factor contributes to the consequences of TBI is likely to aid in the development of approaches to diagnose and treat TBI6,7.
Here we describe a method for inflicting closed head TBI in Drosophila melanogaster (fruit flies) that can be used to delineate the contribution of variable factors to the consequences of TBI. The method is based on an initial observation that intensely hitting the side of a fly culture vial against the palm of a hand caused wild-type flies to become temporarily incapacitated, a likely consequence of TBI. Thus, we constructed the High-Impact Trauma (HIT) device to recapitulate the acceleration and deceleration forces from the hand-hitting action. A high-speed movie shows that a single strike from the HIT device causes flies to contact the vial wall several times with their head and body8. To some extent, all contacts are likely to cause the fly brain to ricochet and deform against the head capsule, similar to what happens to humans in falls and car crashes9. Accordingly, flies treated with the HIT device display phenotypes consistent with brain injury, including temporary incapacitation followed by ataxia, gradual recovery of mobility, gene expression changes in the head, and progressive neurodegeneration in the brain10. Thus, the HIT device makes it possible to study TBI using the enormous arsenal of experimental tools and techniques developed for flies.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>Zinc plated compression spring</td>
			<td>The Hillman&#160; Group</td>
			<td>540189</td>
			<td>9 7/8 in (length), 15/16 in (outer diameter), 0.12 in (wire size)</td>
		</tr>
		<tr>
			<td>Wooden board</td>
			<td></td>
			<td></td>
			<td>9 in (length), 6.5 in (width), 0.75 in (height)</td>
		</tr>
		<tr>
			<td>Clamps</td>
			<td>Sigma Electrical Manufacturing Corporation</td>
			<td>49822</td>
			<td>3.10 in (length), 0.68 in (width), 1.11 in (height), EMT Two Hole Straps, click on type for 1 inch steel EMT conduit</td>
		</tr>
		<tr>
			<td>Loop half of self-adhesive velcro</td>
			<td></td>
			<td></td>
			<td>3 in (length), (3/4 in width)</td>
		</tr>
		<tr>
			<td>Polyurethane ice bucket cover</td>
			<td>Fisher Scientific</td>
			<td>02-591-45</td>
			<td>9 1/8 in (length), 9 1/8 in (width), 1 1/4 in (height)</td>
		</tr>
		<tr>
			<td>Plastic fly vials</td>
			<td>Applied Scientific</td>
			<td>AS-510</td>
			<td>3 11/16 in (height), 1 1/16 in (inner diameter), 1 1/8 in (outer diameter)</td>
		</tr>
		<tr>
			<td>Large cotton balls</td>
			<td>Fisher Scientific</td>
			<td>22-456-883</td>
			<td></td>
		</tr>
		<tr>
			<td>Paper protractor</td>
			<td></td>
			<td></td>
			<td>10 in (diameter)</td>
		</tr>
	</tbody>
</table>

a method to inflict closed head traumatic brain injury in drosophila

Traumatic brain injury (TBI) affects millions of people each year, causing impairment of physical, cognitive, and behavioral functions and death. Studies using Drosophila have contributed important breakthroughs in understanding neurological processes. Thus, with the goal of understanding the cellular and molecular basis of TBI pathologies in humans, we developed the High Impact Trauma (HIT) device to inflict closed head TBI in flies. Flies subjected to the HIT device display phenotypes consistent with human TBI such as temporary incapacitation and progressive neurodegeneration. The HIT device uses a spring-based mechanism to propel flies against the wall of a vial, causing mechanical damage to the fly brain. The device is inexpensive and easy to construct, its operation is simple and rapid, and it produces reproducible results. Consequently, the HIT device can be combined with existing experimental tools and techniques for flies to address fundamental questions about TBI that can lead to the development of diagnostics and treatments for TBI. In particular, the HIT device can be used to perform large-scale genetic screens to understand the genetic basis of TBI pathologies.

We are interested in understanding why flies die shortly after primary injury. To quantify death, we determined the Mortality Index at 24 hr (MI24), which is the percentage of flies that died within 24 hr of the primary injury. Flies subjected to strikes from the HIT device were incubated at 25 &#176;C in a vial with fly food, and the number of dead flies was counted after 24 hr. We used this approach to identify factors that affect the MI24 and found that the MI24 is not affected by the ...

Watch this Scientific Journal Video about A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila at JoVE.com

A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Here we describe a method to inflict closed head traumatic brain injury (TBI) in Drosophila. This method provides a gateway to investigate the cellular and molecular mechanisms that underlie TBI pathologies using the vast array of experimental tools and techniques available for flies.

A Method to Inflict Closed Head Traumatic Brain Injury in Drosophila

Traumatic brain injury (TBI) affects millions of people each year, causing impairment of physical, cognitive, and behavioral functions and death. Studies ...

a-method-to-inflict-closed-head-traumatic-brain-injury-in-drosophila

Research

JoVE Journal

Neuroscience

11.3K visualizações.  University of Wisconsin-Madison.  Aqui nós descrevemos um método para infligir a cabeça fechado traumatismo crânio-encefálico (TCE) em Drosophila. Este método oferece um portal para investigar os mecanismos celulares e moleculares que estão na base patologias TCE, utilizando a vasta gama de ferramentas experimentais e técnicas disponíveis para as moscas. 