We would like to acknowledge Beth Levine for critically reviewing the manuscript, Valerie Tassinari for developing the genotyping protocol, and Matt Ferola and Carlos Maya for their exceptional animal care.

All experiments are conducted in accordance with the protocols described by the National Institutes of Health Guide for the Care and Use of Animals and were approved by ALS TDI&#8217;s institutional animal care and use committee (IACUC).
1. Animals, Housing, and Study Design
Note: The SOD1-G93A mouse colony was derived from the high copy B6SJLTgN(SOD1G93A)1Gur strain originally produced by Gurney et al. 7. The colony is currently being maintained by crossing transgenic C57BL/6-SJL males with wild-type C57BL/6-SJL F1 females. The F1 animals are generated by crossing SJL males with B6 females. Mice are shipped to ALS TDI weekly at 35&#8211;45 days of age.
<ol>
	<li>Allow mice at least one week to acclimate to the animal facility (12-hr light/dark cycle at a temperature of 18-23&#160;&#176;C&#160;and 40-60% humidity) before assigning to a study.</li>
	<li>House male SOD1-G93A mice one mouse per cage, since group housed males tend to fight. House female SOD1-G93A mice up to two&#160;per cage. Provide environmental enrichment, in the form of plastic huts. Provide food and water ad libitum, unless the mice are part of a study requiring drug administration in drinking water/food. In these cases, ration and record food and water.</li>
	<li>Begin a drug-efficacy study around age day 50 and include 64 litter-matched gender-balanced mice (32 per cohort). Finally, ensure that the researchers conducting the studies are blinded to the experimental conditions. 
	Note: It is recommended that a typical drug-efficacy study starts at age day 50 however based on the type of therapeutic intervention it might be preferable to start the study earlier or later. 
	Note: A study with 32 mice per cohort is powered to detect gender-specific drug-effects. If no gender-specific comparisons are required, 24 mice per cohort should suffice to detect overall drug-effects.</li>
</ol>
2. Body Weight
<ol>
	<li>Record body weights for all mice in studies daily with a precision of one tenth of a gram. Note: Body weight is a sensitive indicator of disease progression and of any malaise that might result from chronic drug treatment.</li>
	<li>Mouse body weights vary considerably during the course of a day, being higher in the mornings, thus record them around the same time every day.</li>
</ol>
3. Neurological Scoring System (NeuroScore)
<ol>
	<li>Assess neurological scores (NS) for each mouse daily by observing the mouse under the following three conditions performed sequentially: a) the mouse is suspended by its tail, b) the mouse is allowed to walk, and after the onset of paresis c) the mouse is placed on its side.
	<ol>
		<li>For the tail suspension test, hold the mouse approximately 1.5&#8221; from the base of the tail over the wire top of their home cage for 1-2 sec, away from the food basin, while observing the hindlimbs. Repeat the suspension test 3 times and record the most consistent outcome.</li>
		<li>For the walking test, place the mouse on a clean surface that provides some traction and a walking distance of 25&#160;cm (e.g., a paper towel taped down to prevent slipping). Allow the mouse to walk a total of 75&#160;cm (3X length of the paper towel) while observing its gait.</li>
		<li>For the &#8220;righting reflex&#8221; test, place the mouse on its left or right side and using a stop-watch measure the time it takes to right itself up unassisted from both sides. Note: Only one trial of this test is required.</li>
	</ol>
	</li>
	<li>Determine the NS of each hindlimb (left or right) independently on a scale from 0 to 4. Note: For instance a score of 0, 1 indicates that the left hindlimb NS is 0, while the right hindlimb NS is 1.</li>
	<li>Assign neurological scores (0-4) corresponding to the following set of observations (summary provided in Table 1):
	<ol>
		<li>Assign NS 0 (Pre-symptomatic) if the following is observed: When the mouse is suspended by the tail, the hindlimb presents a normal splay i.e., it is fully extended away from the lateral midline and it stays in this position for 2 sec&#160;or longer. When the mouse is allowed to walk, normal gait is observed.</li>
		<li>Assign NS 1 (First symptoms) if the following is observed: When the mouse is suspended by the tail, the hindlimb presents an abnormal splay, i.e., it is collapsed or partially collapsed towards lateral midline OR it trembles during tail suspension OR it is retracted/clasped. When the mouse is allowed to walk, normal OR slightly slow gait is observed.</li>
		<li>Assign NS 2 (Onset of paresis) if the following is observed: When the mouse is suspended by the tail, the hindlimb is partially OR completely collapsed, not extending much. (There might still be joint movement). When the mouse is allowed to walk, the hindlimb is used for forward motion however the toes curl downwards at least twice during a 90 cm walk OR any part of the foot is dragging along cage bottom/table. When the mouse is placed on its left AND right side, it is able to right itself within 10 sec&#160;from BOTH sides.</li>
		<li>Assign NS 3 (Paralysis) if the following is observed: When the mouse is suspended by the tail, there is rigid paralysis in the hindlimb OR minimal joint movement. When the mouse is allowed to walk there is forward motion however the hindlimb is NOT being used for forward motion. When the mouse is placed on its left AND right side, it is able to right itself within 10 sec&#160;from BOTH sides.&#160;Note: Rarely, after the onset of paralysis, urine moisture might appear on the hindlimbs.&#160; Left untreated urine moisture might result to urine &#8220;burn&#8221; and skin lesions.&#160; Treat urine moisture by clipping the hair, apply warm water soaks to remove the urine, and gently blot dry. If skin lesions are present apply antibiotic ointment.</li>
		<li>Assign NS 4 (Humane end-point) if the following is observed: When the mouse is suspended by the tail, there is rigid paralysis in the hindlimbs. When the mouse is allowed to walk, there is no forward motion. When the mouse is placed on its left AND right side it is NOT able to right itself within 10 sec&#160;from EITHER side. i.e., absence of righting reflex.</li>
	</ol>
	</li>
</ol>
4. Data Entry and Analysis
<ol>
	<li>During the course of a drug efficacy study, enter data collected for each mouse into a Laboratory Information Management System (LIMS) or into a commercially available spreadsheet software. 
	Note: The ALS TDI-developed LIMS software is a central repository for all data collected from internal studies, making these data conveniently accessible over time for ALS TDI investigators. LIMS tracks any individual mouse, with its unique ID, back to its lineage, body weight or neurological score on all study days, and includes any other observations noted during its lifetime. LIMS ultimately generates a spreadsheet which is used for subsequent analyses.</li>
	<li>Upon the completion of a drug efficacy study, i.e., when all mice reach the humane end-point, use spreadsheet software (see Table of Materials) to compute the combined NS for each mouse, for each day by averaging the left and right hindlimb NS. Next, compute the median age at each NS for each mouse and the number of days each mouse spends at a particular NS.</li>
	<li>Analyze overall changes in NS over time by importing the data from the spreadsheet software to the statistical software (see Table of Materials). Fit these data using a model of ordinal logistic regression which estimates the expected NS, with median age at NS and drug-treatment as effects in the regression. Using the log-rank chi square test estimate the effect likelihood probability and determine whether the drug-treatment effect on NS progression is statistically significant (see Supplemental Code File for step-by-step instructions). 
	Note: A p-value &#60;0.05 is considered statistically significant. 
	Note: This method of statistical analysis respects the ordinal nature of the NS data and the variable nature of the NS trajectories for individual mice. It is preferred because individual NS trajectories can be markedly different resulting in NS time-associated group averages that are not sufficiently reflective of NS responses. In addition, in some cases NS can fluctuate, particularly when in the zero-to-one range.</li>
	<li>Finally, use graphing software (see Table of Materials) to generate &#8220;Ordinal Expected NS vs Median Age at NS&#8221; graphs for drug-treated and control animals (Figure 2; see Supplemental Code File for step-by-step instructions). Use these graphs to conveniently estimate shifts between drug-treated and control groups by interpolating from the y-axis the median age of disease onset (i.e., NS 2) on the x-axis. 
	Note: The difference in median age between the two groups represents a drug-induced shift and is treated as a practical measure of the magnitude of effect. 
	Note: Rightward shifts in the expected NS vs. median age curve indicate slowed symptomatic disease progression. Conversely, leftward shifts in the expected NS vs. median age curve indicate accelerated symptomatic disease progression.</li>
</ol>

<ol>
	<li>Gurney, M. E., 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=Motor+neuron+degeneration+in+mice+that+express+a+human+Cu,Zn+superoxide+dismutase+mutation.">Motor neuron degeneration in mice that express a human Cu,Zn superoxide dismutase mutation.</a> Science. 264 (5166), 1772-1775 (1994).</li><li>Rosen, D. R., 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=Mutations+in+Cu/Zn+superoxide+dismutase+gene+are+associated+with+familial+amyotrophic+lateral+sclerosis.">Mutations in Cu/Zn superoxide dismutase gene are associated with familial amyotrophic lateral sclerosis.</a> Nature. 362 (6415), 59-62 (1993).</li><li>Gurney, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+use+of+transgenic+mouse+models+of+amyotrophic+lateral+sclerosis+in+preclinical+drug+studies.">The use of transgenic mouse models of amyotrophic lateral sclerosis in preclinical drug studies.</a> J Neurol Sci. 152, Suppl. 1 (6415), (1997).</li><li>Scott, S., 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=Design,+power,+and+interpretation+of+studies+in+the+standard+murine+model+of+ALS.">Design, power, and interpretation of studies in the standard murine model of ALS.</a> Amyotroph Lateral Scler. 9 (1), 4-15 (2008).</li><li>Hegedus, J., Putman, C. T., Gordon, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time+course+of+preferential+motor+unit+loss+in+the+SOD1+G93A+mouse+model+of+amyotrophic+lateral+sclerosis.">Time course of preferential motor unit loss in the SOD1 G93A mouse model of amyotrophic lateral sclerosis.</a> Neurobiol. Dis. 28 (2), 154-164 (2007).</li><li>Gordon, T., Ly, V., Hegedus, J., Tyreman, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+detection+of+denervated+muscle+fibers+in+hindlimb+muscles+after+sciatic+nerve+transection+in+wild+type+mice+and+in+the+G93A+mouse+model+of+amyotrophic+lateral+sclerosis.">Early detection of denervated muscle fibers in hindlimb muscles after sciatic nerve transection in wild type mice and in the G93A mouse model of amyotrophic lateral sclerosis.</a> Neurol. Res. 31 (1), 28-42 (2009).</li><li>Gurney, M. E., 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=Motor+neuron+degeneration+in+mice+that+express+a+human+Cu,Zn+superoxide+dismutase+mutation.">Motor neuron degeneration in mice that express a human Cu,Zn superoxide dismutase mutation.</a> Science. 264 (5166), 1772-1775 (1994).</li><li>Kim, K., Moore, D. H., Makriyannis, A., Abood, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=AM1241,+a+cannabinoid+CB2+receptor+selective+compound,+delays+disease+progression+in+a+mouse+model+of+amyotrophic+lateral+sclerosis.">AM1241, a cannabinoid CB2 receptor selective compound, delays disease progression in a mouse model of amyotrophic lateral sclerosis.</a> Eur. J. Pharmacol. 542 (1-3), 1-3 (2006).</li><li>Weydt, P., Hong, S. Y., Kliot, M., Moller, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessing+disease+onset+and+progression+in+the+SOD1+mouse+model+of+ALS.">Assessing disease onset and progression in the SOD1 mouse model of ALS.</a> Neuroreport. 14 (7), 1051-1054 (2003).</li><li>Azari, M. F., 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=Behavioural+and+anatomical+effects+of+systemically+administered+leukemia+inhibitory+factor+in+the+SOD1(G93A+G1H)+mouse+model+of+familial+amyotrophic+lateral+sclerosis.">Behavioural and anatomical effects of systemically administered leukemia inhibitory factor in the SOD1(G93A G1H) mouse model of familial amyotrophic lateral sclerosis.</a> Brain Res. 982 (1), 92-97 (2003).</li><li>Guan, Y., 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=Thiazolidinediones+expand+body+fluid+volume+through+PPARgamma+stimulation+of+ENaC-mediated+renal+salt+absorption.">Thiazolidinediones expand body fluid volume through PPARgamma stimulation of ENaC-mediated renal salt absorption.</a> Nat. Med. 11 (8), 861-866 (2005).</li><li>Savcheniuk, O. A., 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=The+effect+of+probiotic+therapy+on+development+of+experimental+obesity+in+rats+caused+by+monosodium+glutamate.">The effect of probiotic therapy on development of experimental obesity in rats caused by monosodium glutamate.</a> Fiziol. Zh. 60 (2), 63-69 (2014).</li><li>Smittkamp, S. E., Brown, J. W., Stanford, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Time-course+and+characterization+of+orolingual+motor+deficits+in+B6SJL-Tg(SOD1-G93A)1Gur/J+mice.">Time-course and characterization of orolingual motor deficits in B6SJL-Tg(SOD1-G93A)1Gur/J mice.</a> Neuroscience. 151 (2), 613-621 (2008).</li><li>C, M., Gurney, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+low+expressor+line+of+transgenic+mice+carrying+a+mutant+human+Cu,Zn+superoxide+dismutase+(SOD1)+gene+develops+pathological+changes+that+most+closely+resemble+those+in+human+amyotrophic+lateral+sclerosis.">A low expressor line of transgenic mice carrying a mutant human Cu,Zn superoxide dismutase (SOD1) gene develops pathological changes that most closely resemble those in human amyotrophic lateral sclerosis.</a> Acta Neuropathol. 93 (6), 537-550 (1997).</li><li>Wegorzewska, I., Baloh, R. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=TDP-43-based+animal+models+of+neurodegeneration:+new+insights+into+ALS+pathology+and+pathophysiology.">TDP-43-based animal models of neurodegeneration: new insights into ALS pathology and pathophysiology.</a> Neurodegener. Dis. 8 (4), 262-274 (2011).</li><li>Hatzipetros, T., 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=C57BL/6J+congenic+Prp-TDP43A315T+mice+develop+progressive+neurodegeneration+in+the+myenteric+plexus+of+the+colon+without+exhibiting+key+features+of+ALS.">C57BL/6J congenic Prp-TDP43A315T mice develop progressive neurodegeneration in the myenteric plexus of the colon without exhibiting key features of ALS.</a> Brain Res. 1584, 59-72 (2014).</li></ol>

The authors have nothing to disclose.

In this report, we describe a quick and simple video protocol which, if properly applied, is capable of reliably assessing the disease progression in SOD1-G93A mice and identifying drug-induced changes. While different groups have developed phenotypic scoring systems for SOD1-G93A mice 8-10, they often do not provide sufficient details on the procedure and are inadequate for replication. As a result, scoring systems are rarely used outside the specific group that develops them. In this report, the combination ...

Ever since its development in the mid 1990&#8217;s the SOD1-G93A transgenic mouse model has been the most widely used animal model of amyotrophic lateral sclerosis (ALS) 1. This transgenic mouse model was genetically engineered to overexpress a mutant form of the human Cu/Zn superoxide dismutase 1(SOD1) gene harboring the ALS-associated glycine to alanine mutation at amino acid 93 (G93A). The G93A mutation is one of many mutations in the SOD1 gene that collectively make-up approximately one fifth of familial ALS cases 2.
The SOD1-G93A model has become a workhorse of ALS drug development research because in addition to its obvious genetic link to ALS, it recapitulates many of the pathological features of ALS in humans such as motor neuron loss, progressive muscle weakness and atrophy, with eventual paralysis and death 3. Though, as is often the case with transgenic animal models, there is an inherent biological variability associated with SOD1-G93A mice. Scott et al. have determined that cohorts of at least 24 litter-matched gender-balanced mice are needed in drug-efficacy study designs in order to overcome the noise created by the biological variability 4. The large number of animals required in these studies in combination with the aggressive disease progression and the need for daily monitoring prohibits the use of elaborate, time-consuming and potentially stressful techniques for measuring neuromuscular strength and function (e.g., electromyography, grip strength, rotorod, etc.). Instead, it highlights the need for an in vivo screening tool that reliably assesses the neuromuscular function of SOD1-G93A mice in a quick manner.
At ALS TDI a protocol was developed that allows for the reliable assessment of the neuromuscular function of SOD1-G93A mice in less than 30 sec&#160;per mouse on average. This protocol encompasses daily assessment of hindlimb function using a simple neurological scoring system (NeuroScore) which is described in this report in press and in video. NeuroScore is focused on hindlimb function because hindlimb deficits are the earliest reported neurological sign of disease in SOD1-G93A mice 5,6. Further, the protocol developed by ALS TDI provides an unbiased assessment of onset of paresis (slight or partial paralysis), progression and severity of paralysis and it is sensitive enough to identify drug-induced changes in disease progression.

<table border="0" cellpadding="0" cellspacing="0">
	<tbody>
		<tr>
			<td>B6SJLTgN(SOD1G93A)1Gur strain</td>
			<td>The Jackson Laboratory, Bar Harbor, ME</td>
			<td>002726</td>
			<td>Strain of mice used in this study</td>
		</tr>
		<tr>
			<td>Breeders</td>
			<td>Biomedical Research Models, Inc., Worcester, MA</td>
			<td></td>
			<td>Colony maintainance</td>
		</tr>
		<tr>
			<td>Scale</td>
			<td>Navigator OHAUS, Parsippany, NJ</td>
			<td>Model N14120</td>
			<td>Used to weigh mice</td>
		</tr>
		<tr>
			<td>Nutra-GelH</td>
			<td>Bio-Serv, Flemington, NJ</td>
			<td>#S4798</td>
			<td>Wet food provided to sick mice</td>
		</tr>
		<tr>
			<td>Irradiated Lab Animal Diet</td>
			<td>Harlan, Indianapolis, IN</td>
			<td>2918-111914M</td>
			<td>Chow diet</td>
		</tr>
		<tr>
			<td>Lab-grade Sani-chips</td>
			<td>Harlan Teklad, Indianapolis, IN</td>
			<td>7090</td>
			<td>Bedding</td>
		</tr>
		<tr>
			<td>JMPH&#160;</td>
			<td>SAS Institute, Inc., SAS Campus Drive, Cary, NC</td>
			<td>&#160;v10.0.2</td>
			<td>Statistical software</td>
		</tr>
		<tr>
			<td>Microsoft Excel</td>
			<td>Microsoft, One Microsoft Way, Redmond, WA</td>
			<td>Excel 2013 (v 15.0)</td>
			<td>Spreadsheet software</td>
		</tr>
		<tr>
			<td>GraphPad Prism 5</td>
			<td>GraphPad software Inc., La Jolla, CA</td>
			<td>v5.4</td>
			<td>Graphing software</td>
		</tr>
		<tr>
			<td>Mouse Huts</td>
			<td>Bio-Serv, Flemington, NJ</td>
			<td>K3272</td>
			<td>For environmental enrichment</td>
		</tr>
	</tbody>
</table>

a quick phenotypic neurological scoring system for evaluating disease progression in the sod1-g93a mouse model of als

The SOD1-G93A transgenic mouse is the most widely used animal model of amyotrophic lateral sclerosis (ALS). At ALS TDI we developed a phenotypic screening protocol, demonstrated in video herein, which reliably assesses the neuromuscular function of SOD1-G93A mice in a quick manner. This protocol encompasses a simple neurological scoring system (NeuroScore) designed to assess hindlimb function. NeuroScore is focused on hindlimb function because hindlimb deficits are the earliest reported neurological sign of disease in SOD1-G93A mice. The protocol developed by ALS TDI provides an unbiased assessment of onset of paresis (slight or partial paralysis), progression and severity of paralysis and it is sensitive enough to identify drug-induced changes in disease progression. In this report, the combination of a detailed manuscript with video minimizes scoring ambiguities and inter-experimenter variability thus allowing for the protocol to be adopted by other laboratories and enabling comparisons between studies taking place at different settings. We believe that this video protocol can serve as an excellent training tool for present and future ALS researchers.

The neurological score data for 90 male and 94 female non-treated SOD1-G93A mice studied at ALS TDI during 2014 were evaluated. The results show that male mice typically have a more aggressive disease progression than female mice, as evidenced by a greater proportion of their lifespan at NS 1 compared to females. NS 2 and NS 3 occur with virtually equal frequency across genders. NS 0 was excluded from the analysis because it is considered a &#8220;normal&#8221; phenotype. NS 4 was also excluded because by definition it c...

Watch this Scientific Journal Video about A Quick Phenotypic Neurological Scoring System for Evaluating Disease Progression in the SOD1-G93A Mouse Model of ALS at JoVE.com

A Quick Phenotypic Neurological Scoring System for Evaluating Disease Progression in the SOD1-G93A Mouse Model of ALS

This video protocol describes a sensitive, reliable, and quick method for evaluating the neuromuscular deficits in a transgenic mouse model of amyotrophic lateral sclerosis.

The SOD1-G93A transgenic mouse is the most widely used animal model of amyotrophic lateral sclerosis (ALS). At ALS TDI we developed a phenotypic screening ...

a-quick-phenotypic-neurological-scoring-system-for-evaluating-disease

Research

JoVE Journal

Medicine

19.2K Views.  ALS Therapy Development Institute. This video protocol describes a sensitive, reliable, and quick method for evaluating the neuromuscular deficits in a transgenic mouse model of amyotrophic lateral sclerosis.

Video: A Quick Phenotypic Neurological Scoring System for Evaluating Disease Progression in the SOD1-G93A Mouse Model of ALS

Development of a Unilaterally-lesioned 6-OHDA Mouse Model of Parkinson's Disease

The unilaterally lesioned 6-hyroxydopamine (6-OHDA)-lesioned rat model of Parkinson's disease (PD) has proved to be invaluable in advancing our understanding of the mechanisms underlying parkinsonian symptoms, since it recapitulates the changes in basal ganglia circuitry and pharmacology observed in parkinsonian patients1-4. However, the precise cellular and molecular changes occurring at cortico-striatal synapses of the output pathways within the striatum, which is the major input region of the basal ganglia remain elusive, and this is believed to be site where pathological abnormalities underlying parkinsonian symptoms arise3,5.
In PD, understanding the mechanisms underlying changes in basal ganglia circuitry following degeneration of the nigro-striatal pathway has been greatly advanced by the development of bacterial artificial chromosome (BAC) mice over-expressing green fluorescent proteins driven by promoters specific for the two striatal output pathways (direct pathway: eGFP-D1; indirect pathway: eGFP-D2 and eGFP-A2a)8, allowing them to be studied in isolation. For example, recent studies have suggested that there are pathological changes in synaptic plasticity in parkinsonian mice9,10. However, these studies utilised juvenile mice and acute models of parkinsonism. It is unclear whether the changes described in adult rats with stable 6-OHDA lesions also occur in these models. Other groups have attempted to generate a stable unilaterally-lesioned 6-OHDA adult mouse model of PD by lesioning the medial forebrain bundle (MFB), unfortunately, the mortality rate in this study was extremely high, with only 14% surviving the surgery for 21 days or longer11. More recent studies have generated intra-nigral lesions with both a low mortality rate &gt;80% loss of dopaminergic neurons, however expression of L-DOPA induced dyskinesia11,12,13,14 was variable in these studies. Another well established mouse model of PD is the MPTP-lesioned mouse15. Whilst this model has proven useful in the assessment of potential neuroprotective agents16, it is less suitable for understanding mechanisms underlying symptoms of PD, as this model often fails to induce motor deficits, and shows a wide variability in the extent of lesion17, 18.
Here we have developed a stable unilateral 6-OHDA-lesioned mouse model of PD by direct administration of 6-OHDA into the MFB, which consistently causes &gt;95% loss of striatal dopamine (as measured by HPLC), as well as producing the behavioural imbalances observed in the well characterised unilateral 6-OHDA-lesioned rat model of PD. This newly developed mouse model of PD will prove a valuable tool in understanding the mechanisms underlying generation of parkinsonian symptoms.

Development of a Unilaterally-lesioned 6-OHDA Mouse Model of Parkinson&#039;s Disease

A protocol for performing unilateral 6-OHDA lesions of the medial forebrain bundle in mice is described. This method has a low mortality rate (13.3 %) with 89% of the surviving animals showing &#62;95% loss of striatal dopamine and 90.63&#177;-4.02 % ipsiversive rotational bias towards the side of the lesion.

The unilaterally lesioned 6-hyroxydopamine (6-OHDA)-lesioned rat model of Parkinson's disease (PD) has proved to be invaluable in advancing our ...

Utilizing Transcranial Magnetic Stimulation to Study the Human Neuromuscular System

Transcranial magnetic stimulation (TMS) has been in use for more than 20 years 1, and has grown exponentially in popularity over the past decade. While the use of TMS has expanded to the study of many systems and processes during this time, the original application and perhaps one of the most common uses of TMS involves studying the physiology, plasticity and function of the human neuromuscular system. Single pulse TMS applied to the motor cortex excites pyramidal neurons transsynaptically 2 (Figure 1) and results in a measurable electromyographic response that can be used to study and evaluate the integrity and excitability of the corticospinal tract in humans 3. Additionally, recent advances in magnetic stimulation now allows for partitioning of cortical versus spinal excitability 4,5. For example, paired-pulse TMS can be used to assess intracortical facilitatory and inhibitory properties by combining a conditioning stimulus and a test stimulus at different interstimulus intervals 3,4,6-8. In this video article we will demonstrate the methodological and technical aspects of these techniques. Specifically, we will demonstrate single-pulse and paired-pulse TMS techniques as applied to the flexor carpi radialis (FCR) muscle as well as the erector spinae (ES) musculature. Our laboratory studies the FCR muscle as it is of interest to our research on the effects of wrist-hand cast immobilization on reduced muscle performance6,9, and we study the ES muscles due to these muscles clinical relevance as it relates to low back pain8. With this stated, we should note that TMS has been used to study many muscles of the hand, arm and legs, and should iterate that our demonstrations in the FCR and ES muscle groups are only selected examples of TMS being used to study the human neuromuscular system.

Transcranial magnetic stimulation (TMS) is a non-invasive tool to gain insight on the physiology and function of the human nervous system. Here, we present our TMS techniques to study cortical excitability of the upper limb and lumbar musculature.

Transcranial magnetic stimulation (TMS) has been in use for more than 20 years 1, and has grown exponentially in popularity over the past decade.  While ...

Use of Animal Model of Sepsis to Evaluate Novel Herbal Therapies

Sepsis refers to a systemic inflammatory response syndrome resulting from a microbial infection. It has been routinely simulated in animals by several techniques, including infusion of exogenous bacterial toxin (endotoxemia) or bacteria (bacteremia), as well as surgical perforation of the cecum by cecal ligation and puncture (CLP)1-3. CLP allows bacteria spillage and fecal contamination of the peritoneal cavity, mimicking the human clinical disease of perforated appendicitis or diverticulitis. The severity of sepsis, as reflected by the eventual mortality rates, can be controlled surgically by varying the size of the needle used for cecal puncture2. In animals, CLP induces similar, biphasic hemodynamic cardiovascular, metabolic, and immunological responses as observed during the clinical course of human sepsis3. Thus, the CLP model is considered as one of the most clinically relevant models for experimental sepsis1-3.
Various animal models have been used to elucidate the intricate mechanisms underlying the pathogenesis of experimental sepsis. The lethal consequence of sepsis is attributable partly to an excessive accumulation of early cytokines (such as TNF, IL-1 and IFN-&gamma;)4-6 and late proinflammatory mediators (e.g., HMGB1)7. Compared with early proinflammatory cytokines, late-acting mediators have a wider therapeutic window for clinical applications. For instance, delayed administration of HMGB1-neutralizing antibodies beginning 24 hours after CLP, still rescued mice from lethality8,9, establishing HMGB1 as a late mediator of lethal sepsis. The discovery of HMGB1 as a late-acting mediator has initiated a new field of investigation for the development of sepsis therapies using Traditional Chinese Herbal Medicine. In this paper, we describe a procedure of CLP-induced sepsis, and its usage in screening herbal medicine for HMGB1-targeting therapies.

Sepsis refers to a systemic inflammatory response syndrome resulting from a microbial infection, and can be simulated by a surgical technique termed cecal ligation and puncture (CLP). Here we describe a method to use CLP-induced animal model to screen medicinal herbs for therapeutic agents.

Sepsis refers to a systemic inflammatory response syndrome resulting from a microbial infection. It has been routinely simulated in animals by several ...

Clinical Testing and Spinal Cord Removal in a Mouse Model for Amyotrophic Lateral Sclerosis (ALS)

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in progressive degeneration of motoneurons. Peak of onset is around 60 years for the sporadic disease and around 50 years for the familial disease. Due to its progressive course, 50% of the patients die within 30 months of symptom onset. In order to evaluate novel treatment options for this disease, genetic mouse models of ALS have been generated based on human familial mutations in the SOD gene, such as the SOD1 (G93A) mutation. Most important aspects that have to be evaluated in the model are overall survival, clinical course and motor function. Here, we demonstrate the clinical evaluation, show the conduction of two behavioural motor tests and provide quantitative scoring systems for all parameters. Because an in depth analysis of the ALS mouse model usually requires an immunohistochemical examination of the spinal cord, we demonstrate its preparation in detail applying the dorsal laminectomy method. Exemplary histological findings are demonstrated. The comprehensive application of the depicted examination methods in studies on the mouse model of ALS will enable the researcher to reliably test future therapeutic options which can provide a basis for later human clinical trials.

Clinical Testing and Spinal Cord Removal in a Mouse Model for Amyotrophic Lateral Sclerosis ALS

A mouse model for amyotrophic lateral sclerosis (ALS) is examined clinically and behaviorally. As a prerequisite for an accompanying immunohistological analysis the preparation of the spinal cord is depicted in detail.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder resulting in progressive degeneration of motoneurons. Peak of onset is around 60 ...

A Simple Method of Mouse Lung Intubation

A simple procedure to intubate mice for pulmonary function measurements would have several advantages in longitudinal studies with limited numbers or expensive animal. One of the reasons that this is not done more routinely is that it is relatively difficult, despite there being several published studies that describe ways to achieve it. In this paper we demonstrate a procedure that eliminates one of the major hurdles associated with this intubation, that of visualizing the trachea during the entire time of intubation. The approach uses a 0.5 mm fiberoptic light source that serves as an introducer to direct the intubation cannula into the mouse trachea. We show that it is possible to use this procedure to measure lung mechanics in individual mice over a time course of at least several weeks. The technique can be set up with relatively little expense and expertise, and it can be routinely accomplished with relatively little training. This should make it possible for any laboratory to routinely carry out this intubation, thereby allowing longitudinal studies in individual mice, thereby minimizing the number of mice needed and increasing the statistical power by using each mouse as its own control.

This paper describes a striaghforward and efficient method of intubating mice for pulmonary function measurements or pulmonary instillation, that allows the mice to recover and be studied at later times. The procedure involves an inexpensive fiberoptic light source that directly illuminates the trachea.

A  simple procedure to intubate mice for pulmonary function measurements would  have several advantages in longitudinal studies with limited numbers or  ...

Bioluminescent Orthotopic Model of Pancreatic Cancer Progression

Pancreatic cancer has an extremely poor five-year survival rate of 4-6%. New therapeutic options are critically needed and depend on improved understanding of pancreatic cancer biology. To better understand the interaction of cancer cells with the pancreatic microenvironment, we demonstrate an orthotopic model of pancreatic cancer that permits non-invasive monitoring of cancer progression. Luciferase-tagged pancreatic cancer cells are resuspended in Matrigel and delivered into the pancreatic tail during laparotomy. Matrigel solidifies at body temperature to prevent leakage of cancer cells during injection. Primary tumor growth and metastasis to distant organs are monitored following injection of the luciferase substrate luciferin, using in vivo imaging of bioluminescence emission from the cancer cells. In vivo imaging also may be used to track primary tumor recurrence after resection. This orthotopic model is suited to both syngeneic and xenograft models and may be used in pre-clinical trials to investigate the impact of novel anti-cancer therapeutics on the growth of the primary pancreatic tumor and metastasis.

Improved understanding of pancreatic cancer biology is critically needed to enable the development of better therapeutic options to treat pancreatic cancer. To address this need, we demonstrate an orthotopic model of pancreatic cancer that permits non-invasive monitoring of cancer progression using in vivo bioluminescence imaging.

Pancreatic cancer has an extremely poor five-year survival rate of 4-6%.  New therapeutic options are critically needed and depend on improved ...

Flexible Colonoscopy in Mice to Evaluate the Severity of Colitis and Colorectal Tumors Using a Validated Endoscopic Scoring System

The use of modern endoscopy for research purposes has greatly facilitated our understanding of gastrointestinal pathologies. In particular, experimental endoscopy has been highly useful for studies that require repeated assessments in a single laboratory animal, such as those evaluating mechanisms of chronic inflammatory bowel disease and the progression of colorectal cancer. However, the methods used across studies are highly variable. At least three endoscopic scoring systems have been published for murine colitis and published protocols for the assessment of colorectal tumors fail to address the presence of concomitant colonic inflammation. This study develops and validates a reproducible endoscopic scoring system that integrates evaluation of both inflammation and tumors simultaneously. This novel scoring system has three major components: 1) assessment of the extent and severity of colorectal inflammation (based on perianal findings, transparency of the wall, mucosal bleeding, and focal lesions), 2) quantitative recording of tumor lesions (grid map and bar graph), and 3) numerical sorting of clinical cases by their pathological and research relevance based on decimal units with assigned categories of observed lesions and endoscopic complications (decimal identifiers). The video and manuscript presented herein were prepared, following IACUC-approved protocols, to allow investigators to score their own experimental mice using a well-validated and highly reproducible endoscopic methodology, with the system option to differentiate distal from proximal endoscopic colitis (D-PECS).

Over the past few years, new generation endoscopes have emerged as important diagnostic research aids for evaluating murine colitis and colorectal tumors. We present herein a detailed protocol for endoscopic assessment of inflammation and colorectal tumors in mice, as well as a novel scoring system that uses decimal identifiers to document the endoscopic severity of colitis and colorectal tumors.

The use of modern endoscopy for research purposes has greatly facilitated our understanding of gastrointestinal pathologies. In particular, experimental ...

Establishment and Characterization of UTI and CAUTI in a Mouse Model

Urinary tract infections (UTI) are highly prevalent, a significant cause of morbidity and are increasingly resistant to treatment with antibiotics. Females are disproportionately afflicted by UTI: 50% of all women will have a UTI in their lifetime. Additionally, 20-40% of these women who have an initial UTI will suffer a recurrence with some suffering frequent recurrences with serious deterioration in the quality of life, pain and discomfort, disruption of daily activities, increased healthcare costs, and few treatment options other than long-term antibiotic prophylaxis. Uropathogenic Escherichia coli (UPEC) is the primary causative agent of community acquired UTI. Catheter-associated UTI (CAUTI) is the most common hospital acquired infection accounting for a million occurrences in the US annually and dramatic healthcare costs. While UPEC is also the primary cause of CAUTI, other causative agents are of increased significance including Enterococcus faecalis. Here we utilize two well-established mouse models that recapitulate many of the clinical characteristics of these human diseases. For UTI, a C3H/HeN model recapitulates many of the features of UPEC virulence observed in humans including host responses, IBC formation and filamentation. For CAUTI, a model using C57BL/6 mice, which retain catheter bladder implants, has been shown to be susceptible to E. faecalis bladder infection. These representative models are being used to gain striking new insights into the pathogenesis of UTI disease, which is leading to the development of novel therapeutics and management or prevention strategies.

The ability to model urinary tract infections (UTI) is crucial in order to be able to understand bacterial pathogenesis and spawn the development of novel therapeutics. This work&#8217;s goal is to demonstrate mouse models of experimental UTI and catheter associated UTI that recapitulate and predict findings seen in humans.

Urinary tract infections (UTI) are highly prevalent, a significant cause of morbidity and are increasingly resistant to treatment with antibiotics. ...

Echocardiographic Approaches and Protocols for Comprehensive Phenotypic Characterization of Valvular Heart Disease in Mice

The aim of this manuscript and accompanying video is to provide an overview of the methods and approaches used for imaging heart valve function in rodents, with detailed descriptions of the appropriate methods for anesthesia, the echocardiographic windows used, the imaging planes and probe orientations for image acquisition, the methods for data analysis, and the limitations of emerging technologies for the evaluation of cardiac and valvular function. Importantly, we also highlight several future areas of research in cardiac and heart valve imaging that may be leveraged to gain insights into the pathogenesis of valve disease in preclinical animal models. We propose that using a systematic approach to evaluating cardiac and heart valve function in mice can result in more robust and reproducible data, as well as facilitate the discovery of previously underappreciated phenotypes in genetically-altered and/or physiologically-stressed mice.

This protocol provides a detailed description of the echocardiographic approach for comprehensive phenotyping of heart and heart valve function in mice.

The aim of this manuscript and accompanying video is to provide an overview of the methods and approaches used for imaging heart valve function in ...

Evaluating the Procedure for Performing Awake Cystometry in a Mouse Model

Awake filling cystometry has been used for a long time to evaluate bladder function in freely moving mice, however, the specific methods used, vary among laboratories. The goal of this study was to describe the microsurgical procedure used to implant an intravesical tube and the experimental technique for recording urinary bladder pressure in an awake, freely moving mouse. In addition, experimental data is presented to show how surgery, as well as tubing type and size, affect lower urinary tract function and recording sensitivity. The effect of tube diameter on pressure recording was assessed in both polyethylene and polyurethane tubing with different internal diameters. Subsequently, the best performing tube from both materials was surgically implanted into the dome of the urinary bladder of male C57BL/6 mice. Twelve-hour, overnight micturition frequency was recorded in healthy, intact animals and animals 2, 3, 5, and 7 days post-surgery. At harvest, bladders were assessed for signs of swelling using gross observation and were subsequently processed for pathological analysis. The greatest extent of bladder swelling was observed on day 2 and 3, which correlated with behavioral voiding data showing significantly impaired bladder function. By day 5, bladder histology and voiding frequency had normalized. Based on the literature and evidence provided by our studies, we propose the following steps for in vivo recording of intravesical pressure and voided volume in an awake mouse: 1) Perform the surgery using an operating microscope and microsurgical tools, 2) Use polyethylene-10 tubing to minimize movement artifacts, and 3) Perform cystometry on post-operative day 5, when bladder swelling resolves.

This study describes the surgical procedures and experimental techniques for performing awake cystometry in a freely moving mouse. In addition, it provides experimental evidence to support its optimization and standardization.

Awake filling cystometry has been used for a long time to evaluate bladder function in freely moving mice, however, the specific methods used, vary among ...