1. The Effects of Ultrasound on Planarian Photoreceptor Regeneration
ANDREW TAGLE | ROSE-ANNE NICOLAS | JASMINE REYES | BEZA NEGUSSIE

2. Why this topic?
◦Personal interests:
◦Diagnostic imaging
◦Ultrasound and skincare (Hissong, et. al)
◦ Application of ultrasound has shown:
◦ Accelerated muscle healing in rats (Montali et. al)
◦ Enhanced blood flow, increased membrane
permeability, altered connective tissue
permeability and nerve conduction in living tissue
(Binder et. al)
◦ Faster bone regeneration in rabbits (Takebe et. al)
◦ Treatment of Alzheimer's in rats (Hynynen et. al)

3. Planaria
◦ Capable of regenerating lost body
parts
◦ Pieces up to 1/279th of the
organism can still regenerate a
head
◦ Contain tissues and organs
homologous to humans
◦ Model organism for investigating
regeneration

4. Background
Morphological and Functional Recovery of the Planarian Photosensing System during Head Regeneration
-Takeshi Inoue, et. Al
◦ Planaria exhibit negative phototaxis
(light avoidance behavior)
◦ Intact planaria able to detect
direction of light
◦ Decapitated planaria unable to
recognize direction of light

5. Planaria Exhibit Negative Phototaxis by Day 5
Morphological and Functional Recovery of the Planarian Photosensing System during Head Regeneration-Takeshi Inoue, et. Al

6. Question
What effect does ultrasound have on planaria
photoreceptor regeneration?

7. Previous Ultrasound Experiment
◦ Applied ultrasound different days after cut
◦ Concluded that applying ultrasound one day after decapitation
was most beneficial
Ultrasound’s effects on planarian photoreceptor regeneration-Chan et., al
◦ Challenges: Budding

8. How can we stop budding?
◦Planaria will bud (fission) and split
apart from each other
◦ Ran experiments to reduce
budding
◦ Cut in two different areas
◦ Placed planaria in 100 mL of
water or 200 mL of water

9. Tail Pieces Reduce Budding

10. Voltage Test
◦Find voltage to use for ultrasound application
◦3 Groups that receive 60 seconds of ultrasound
◦200 mV (n=10)
◦300 mV (n=10)
◦400 mV (n=10)
◦ Timed how long it takes for each planaria to
escape inner ring

11. Voltage Test Results

12. Voltage Test Results

13. Physical Differences

14. Ultrasound Application
◦ Planaria cut near tail to reduce budding 24 hours . . .
◦ Planaria were treated with 200 mV of
ultrasound ~24 hours after being cut
◦ 3 groups (n=36)
◦ Control: No treatment (n=12)
◦ 1 treatment (n=12)
◦ 2 treatments (n=12)
◦ Proceed with phototaxis assay

15. How to Test Photoreceptor Function
◦ Planaria exhibit negative phototaxis
◦ Shadow box
◦ Acclimate planaria to dark ~15
minutes prior to testing
◦ Conducted in a dark room
◦ Test for 90 seconds
◦ Conduct assay on Day 0 and
Day 3-Day 7 and on day 9
◦ Hoped to see difference
between treated planaria
and control.

16. Control Results
Shadow Box Results
*** ***
***
**
NS
***
= p < 0.001
= p < 0.01
NS = Non Significant
***
**

17. Control vs. 1 US Treatment Results
Shadow Box Results
NS
NS
***
*****
*** ***
*** ***
***
*
**
**
**
*
= p < 0.001
= p < 0.01
NS = Non Significant
*
*

18. Control vs. 2 US Treatment Results
Shadow Box Results
NS
NS
NS
*** ***
*** ***
***
*** ***
**
**
**
*
= p < 0.001
= p < 0.01
NS = Non Significant
*
*

19. Summary
◦Using tail piece of planaria help reduce budding
◦Applying 2 doses of 200 mV of ultrasound at 30 minutes aparts
improves photoreceptor regeneration
◦Takes ~7-9 days for tail piece to reach day 0 performance in phototaxis
assay

20. Future Directions
◦More than 2 treatment groups
◦Run assay for a longer period (>90 seconds)

21. Acknowledgements
◦ Bryan White
◦ Pierre Mourad
◦ Cameron Whalen
◦ Ivan Owen
◦ Engineering program for sharing their lab with us

22. Questions?