Abstract

This project tested berberine, upon Drosophila melanogaster that have been induced with Parkinson’s.  It was hypothesized the greater the concentration of berberine the quicker the drosophila would move up their mobility assay and would increase the distance covered in their crawling assay.  Male Gal 4 flies were crossed with Alpha Synuclein females and placed in differing concentrations of berberine.  Berberine enhanced their mobility compared to the control in both assays (p<.05). 

Rationale

Sixty thousand people are diagnosed every year with Parkinson’s disease. Research has shown a connection between Parkinson’s Disease and a reduction in insulin receptors in the dopaminergic region of the brain.  Berberine is a natural substance used by the Chinese for centuries that has gained a new application in helping with type 2 diabetics.  Because both diseases appear to have a similar link, it was hypothesized that adding more berberine to Drosophila melanogaster that have been induced with Parkinson’s would result in increased mobility in the flies. 

Experimental Design

Create 24 vials- 6 each of 0, 1, 100, 1000 ppm berberine, 4 g potato media, and yeast.  Anesthetize Gal4 fly starter vial, place flies under a microscope, and put two males into each vial.  Obtain two virgin alpha synuclein flies in the same way for each vial.  Leave adults together until larva emerge.  Remove adult flies and dispose of in alcohol morgue.

Perform Larva Crawling Test

Add 50mL of 20% sucrose solution to three vials of each concentration (0, 1, 100, 1000ppm) with larva and let sit for 20 minutes so larva float to top.  Collect larva using pipette and place in filter paper.  Wash larvae on filter paper with distilled water.  Put larva in petri dish containing 2% agarose over graph paper.  Count the number of grid lines crossed in a minute

ET50 test

Place about 10 flies from 0 ppm vial into motor tube.  Time flies until half cross the midpoint.  Record time.  Repeat with other vials (two other controls, 1, 100, 1000 ppm)

Results

In the flying assay, all concentrations of berberine (1, 100, and 1000ppm) compared to the controls have a reduced time for half of the Parkinson induced flies to perform their flying assay (average ET50s were 10.6, 5.4, 6.6., 6.4 sec).  In the crawling trials, larva exposed to berberine were able to travel a further average distance than the controls (3.3, 5.9, 6.4, 7.9 lines).  There was a positive correlation between the amount given and the lines crossed in crawling assay. 

Table 1

Table 2

Discussion

This project attempted to see if there was a correlation between the amount of berberine consumed upon the mobility of Parkinson’s induced Drosophila melanogaster in both larval and adult phases.  It was hypothesized that as the concentration of berberine increased the adult flies would be faster in their flying assay and that larva would cover a greater distance in their crawling assay.  Compared to the controls in the flying assay, Drosophila exposed to berberine did have a shorter ET50 (p < .05).  In the crawling assay, the larva exposed to berberine were able to travel further than the controls (p < .05).  Moreover, there was a positive correlation (p < .01) between increasing amounts of berberine and distance the larva crawled.  Therefore, the hypothesis was supported.  The results of this study suggest that further experimentation should be performed using berberine to see if similar results are obtained in other organisms. 

Acknowledgements:

Thank you to my research instructor, Lisa Garrido, who trained me in experimental methodology as well as Bloomington Drosophila Stock Center for guidance with which flies to mate and for the Gal4 and Alpha Synuclein flies.

Citations

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