Quantitative Evaluation of Oromotor Function:
A Simple and Stress-free Test for Motor Behavior
Roland Rabl, Adam Horvath, Birgit Hutter-Paier
QPS Neuropharmacology, Parkring 12, 8074 Grambach, Austria
RESULTS
Pasta Gnawing test compared to Rota Rod and Wire Hanging
performance of TNWT#61 mice
0.35
0.25
6
[n]
0.15
***
50
***
0
2
[s]
3
25
0
6
age [months]
wire hanging time
***
***
50
0
2
6
75
1
0.00
***
100
2
0.05
3
age [months]
D
4
3
0.10
*
100
5
0.20
**
[s]
7
2
TNWT#61
3
wt
6
age [months]
2
3
6
age [months]
Figure 1. Motor evaluation of TNWT#61 animals. Gnawing interval duration (A) and gnawing peaks per episode
(B) of TNWT#61 male animals compared to wildtype (wt) littermates as well as latency to fall off the Rota Rod (C)
and wire hanging time (D) of the same animals. n=10-15 per group and age; Statistical analysis: Two-way-ANOVA
followed by Bonferroni post-test, * p<0.05; **p<0.01; ***p<0.001.
TNWT#61 mice showed progressive motor impairments starting at 3 months of age compared to wt littermates
in terms of gnawing peaks per episode (B) in the Pasta Gnawing test. Highly significant differences were also
observed at all ages in the Rota Rod (C) and wire hanging performance (D). Evaluation of the gnawing interval
duration (A) did not reach significance, but showed a trend of decreasing gnawing speed in TNWT#61 mice.
Pasta Gnawing test compared to Rota Rod and Wire Hanging
performance of TDP43xTDP43 mice
8
6
0.25
C
175
0.15
100
75
50
25
0
6
4
D
100
0.10
2
75
0.05
1
0.00
0
age [weeks]
[s]
3
6
*
150
5
0.20
latency to fall Rota Rod
125
7
0.30
[s]
gnawing peaks per episode
***
time [s]
0.35
B
gnawing interval length
*
20
age [weeks]
wire hanging time
***
***
50
25
6
20
age [weeks]
20
0
6
20
age [weeks]
wt
TDP-43xTDP-43
Figure 2. Motor evaluation of TDP43xTDP43 animals. Gnawing interval duration (A) and gnawing peaks per
episode (B) of TDP43xTDP43 animals compared to wt littermates as well as latency to fall off the Rota Rod (C)
and wire hanging time (D) of the same animals. n=5-16 per group and age; Statistical analysis: Two-way-ANOVA
followed by Bonferroni post-test, * p<0.05; ***p<0.001.
TDP43xTDP43 mice showed progressive motor impairments compared to wt littermates in terms of gnawing
peaks per episode (B) in the Pasta Gnawing test similar to the Rota Rod (C). Evaluation of the Wire hanging
performance (D) resulted in highly significant differences at both ages. Furthermore, a significant decrease of
gnawing speed (A) could be detected at 20 weeks of age.
Pasta Gnawing test compared to Rota Rod and Wire Hanging
performance of NPC1 ko mice
B
gnawing interval duration
0.35
8
0.30
7
*
6
5
0.20
[n]
[s]
C
gnawing peaks per episode
[s]
A
0.25
Two parameters were evaluated:
• Biting speed (gnawing
interval length)
• Number of bites during a
chewing period (gnawing
peaks per episode).
***
0.15
90
80
70
60
50
40
30
20
10
0
4
D
3
100
0.10
2
75
0.05
1
0.00
0
6
age [weeks]
*
8
age [weeks]
wire hanging duration
50
25
6
8
NPC -/-
latency to fall Rota Rod
6
[s]
To measure gnawing noise, we placed a microphone above the
home cage and put dry spaghetti pieces (approx. 1 cm long) into
the home cage. Afterwards, we recorded the gnawing noise.
Acquisition was performed by using a Behringer ECM 8000
microphone connected to a Steinberg Cl1 audio interface.
Steinberg Wave Lab LE 7 was used as recording software. The
acquired gnawing pattern was analyzed using sound analyzing
software (Avisoft SASLab Pro 5.1).
latency to fall Rota Rod
8
0.30
A
Two hours prior to testing, animals were brought to the sound proof
cabinet and the food pellets were removed. One little piece of dry
spaghetti was given to each animal to become familiar with the
novel food.
C
150
MATERIALS AND METHODS
Mouse models of Parkinsons disease (TNWT#61 – Line61),
Amyotrophic lateral sclerosis (TAR6/6 – TDP43x TDP43),
Niemann-Pick disease (NPC1 ko/ko) and corresponding wild type
(WT) mice were tested at various ages.
B gnawing peaks per episode
A gnawing interval duration
[n]
Measuring motor behavior in rodent disease models is often
performed in long lasting tests with time consuming evaluations
(paper pencil) under high stress conditions (e.g. Rota Rod,
Challenging Beam Walk). Beyond that, results of these tests are
influenced by body constitution (esp. body weight) and the
emotional status of the animals. In 2011, Kane et al. noticed, that
when performing a Pasta handling test for evaluating the lesion rate
of unilaterally 6-OHDA lesioned rats, not only the number of
adjustments with each paw was altered, but also the gnawing noise
was different. Since various neurodegenerative diseases like
Parkinson`s disease, Amyotrophic lateral sclerosis and NiemannPick disease are accompanied by speech and swallowing
disturbances or mask-like face expressions in humans, we wanted
to check whether this finding could also be observed in motor
impaired transgenic mice. Therefore, we evaluated the gnawing
noise of three mouse models of three different indications
containing motor deficits and compared the results with the
performance in the Rota Rod and Wire Hanging Test.
[s]
BACKGROUND
wt
age [weeks]
8
0
6
8
age [weeks]
Figure 3. Motor evaluation of NPC1 ko animals. Gnawing interval duration (A) and gnawing peaks per episode (B)
of NPC1 ko animals compared to wt littermates as well as latency to fall off the Rota Rod (C) and wire hanging
time (D) of the same animals. n=9-12 per group and age; Statistical analysis: Two-way-ANOVA followed by
Bonferroni post-test, * p<0.05;
NPC1 ko mice showed motor impairments compared to wt littermates in terms of gnawing peaks per episode at
an age of 8 weeks (B) in the Pasta Gnawing test similar to the Rota Rod (C). Gnawing speed (A) and wire hanging
duration (D) were not affected by the genotype.
CONCLUSION
Our results show, that the Pasta gnawing test is capable to quantitatively detect motor
disturbances in mouse models of various neurodegenerative diseases similar to
conventional motor tests. We furthermore were able to detect a more robust sensitivity
towards disease progression compared to Rota Rod and Wire Hanging Test.
As a conclusion, the Pasta Gnawing Test displays a novel, powerful tool to
characterize mouse models of neurodegenerative diseases, as well as for efficacy
tests investigating new compounds. Simultaneously, the test is especially sensitive
resulting in more robust results and also more importantly, reducing stress caused by
animal handling compared to use of other motor tests.
Contact: Roland Rabl I Preclinical Research Associate I QPS Austria GmbH I Parkring 12 I 8074 Grambach I Austria
[email protected] I www.qpsneuro.com
Measuring Behavior 2016, ID:77, P21