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The Behavioral Effects of Aspartame Exposure
to Black Planaria (Dugesia dorotocephala)
http://s399.photobucket.com/user/chelseybrownfield/media/Lab%2022%20Specimesns/151.jpg.html
Jessica L. Pratt
Department of Biological Sciences, York College of Pennsylvania
Abstract
Pilot Study
10 planaria
Control
No aspartame
Objective
To determine if there are behavioral and mobility changes
after periodic exposure at a low and high aspartame
concentration.
Hypotheses
H1: There are changes in behavior and mobility of black
planaria when exposed to aspartame.
H2: Changes in behavior and mobility are more frequent as
aspartame concentrations increase.
10 planaria
Low
concentration
High
concentration
0.001 M
0.01 M
Placed in
recording petri
dish & video
recorded planaria
for 8 minutes
Behavior
Time
Subjects
Interaction
Head Bop
0.0754
0.0321*
0.9978
Squirming
0.0176*
0.8850
0.0036**
Twitching
Head Swing
0.0001***
0.0082**
0.7247
0.0256*
0.1792
0.1366
Discussion
http://www.mindsetsonline.co.uk/Catalogue/ProductDetail/petri-dish?productID=c52d0927-e398-4efc-906e74c0ca95d5bf&catalogueLevelItemID=09ce19f0-e14f-4f2f-99f3-a017466a71e6
http://www.carolina.com/lab-dishes/stender-dish-stacking-type-37-x-25mm/741012.pr;jsessionid=DED2236040ED1740770F47D6EBA4AC27.stageworker2?catId=10261&mCat=&sCat=&ssCat=&questio
n=
Behavior
P < 0.05*
P < 0.01**
P < 0.001***
Placed in dilution
dish
• Planaria are freshwater flatworms which are used as an animal
model in developmental biology and neuropharmacology research
(Raffa and Desai 2005, Pagán et al. 2009). Planaria are known to
respond behaviorally to various stimuli such as cocaine,
amphetamines, and opiates (Pagán et al. 2009).
• There is debate if aspartame is a safe product although it has been
approved by the FDA because of its metabolic components. Some of
aspartame’s metabolic components, however, can cause changes in
the production of neurotransmitters, or when broken down can be
very cytotoxic. There is an ongoing debate among researchers
whether aspartame causes developmental, behavioral, and
neurological effects (Humphries et al. 2007).
10 planaria
Exposed for 120
minutes
Introduction
• Aspartame is a popular artificial sweetener which is used in a large
assortment of products. The presence of aspartame in products that
are used on a daily basis is growing and not restricted to only sugarfree or unsweetened products.
Table 1. Two-way ANOVA summary.
Methods
Aspartame is a popular artificial sweetener used in a large array of products.
There is an ongoing debate among researchers whether aspartame causes
developmental, behavioral, and neurological effects. This study investigated
whether changes in behavior and mobility of the black planaria (Dugesia
dorotocephala) occurred after periodic exposures to low (0.001 M) and high
(0.01 M) aspartame concentrations. The control, low, and high concentration
groups were kept in separate glass dishes and given fresh water every 3 days
after a feeding. Exposures to aspartame or control water occurred in
microcentrifuge tubes for 2 hours. This protocol proceeded for 29 days where
single-blind observations were recorded every other day. The behaviors
searched for were head bopping, head swinging, twitching, cork screwing,
squirming, and inch worming. As treatment to aspartame occurred over time a
decrease in mobility was observed in planaria. A decrease in mobility was also
observed in the control group which gives reason to believe an outside factor
could be responsible. Treatment groups differed significantly in the number of
head bops and head swings observed. Squirming behavior amounts differed
significantly when aspartame concentrations increased. The amount of time
the planaria were treated significantly affected the amount of squirming,
twitching, and head swinging observed. The amount of time the planaria were
treated on the first day against the last significantly affected the amounts of
head swings and squirms observed. There were changes in behavior and
mobility of black planaria when exposed to aspartame. Changes in behavior
and mobility were not more frequent as aspartame concentrations increased.
Chemdraw
Mobility
• As treatment to aspartame occurred over time a decrease in mobility
was observed in planaria, along with the control group. The outside factor
hypothesized to be responsible was contaminated river water from the
collection site at Tyler Run Creek (Figure 1).
• Treatment groups differed significantly in the number of head bops and
head swings (Table 1).
• Squirming behavior amounts differed significantly when aspartame
concentrations increased (Table 1, Figure 4).
• The amount of time the planaria were treated significantly affected the
amount of squirming, twitching, and head swinging (Table 1).
• The amount of time the planaria were treated on the first day vs the last
day, significantly affected the amounts of head swings and squirms
observed (Figure 2, Figure 4).
Conclusions
Head Bopping
Head Swinging
Twitching
Cork Screwing
Results
Squirming
Inch Worming
• There were changes in behavior and mobility of black planaria when
exposed to aspartame.
• Changes in behavior and mobility were not more frequent as aspartame
concentrations increased.
• The decrease in mobility within the control group gives reason to believe
an outside factor was responsible.
Literature Cited
• Humphries, P.P., Pretorius, E.E., and Naudé, H.H. (2008). Direct and indirect cellular
effects of aspartame on the brain. European Journal Of Clinical Nutrition
[09543007] 62(4): 451-462.
• Lavin, J., French, S., & Read, N. (1997). The effect of sucrose- and aspartamesweetened drinks on energy intake, hunger and food choice of female, moderately
restrained eaters. International Journal Of Obesity & Related Metabolic Disorders
[03070565] 21(1): 37.
• Pagán, R.O., Coudron, T., and Kaneria, T. (2009). The Flatworm Planaria as a
Toxicology and Behavioral Pharmacology Animal Model in Undergraduate Research
Experiences. The Journal of Undergraduate Neuroscience Education [serial online]
7(2): A48-A52.
• Pagán R.O., Rowlands, L.A., and Urban R.K. 2006. Toxicity and behavioral effects of
dimethylsulfoxide in planaria. Neuroscience Letters. [0304-3940] 407(3): 274-278.
• Raffa, B.R. and Desai, P. 2005. Description and quantification of cocaine withdrawal
signs in Planaria. Brain Research [0006-8993] 1032(1-2): 200-202.0
Acknowledgements
I would like to thank York College of Pennsylvania for funding my research.
I would like to thank Dr. Rehnberg for his guidance throughout the
entirety of my research. I would like to thank Dr. Hagerty for her advice in
the analysis of my data. I would like to thank Joan Carpenter for her
continuous help in ensuring lab access throughout the summer months.
Lastly, I would like to thank TJ Steckbeck, Masi Luttner, and Emily Springer
for assisting me during the course of my research.
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