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Name: Phillip B.
Status: Student
Age: 14
Location: N/A
Country: N/A
Date: N/A 

In my AP Biology class, we have begun designing experiments which are pretty much just limited by what one can do with fruit flies. My partner and I became interested in somehow incorporating Saint John's Wort into our experiment. I read articles at which mentioned that the FDA believes Saint John's Wort may be safe when taken by itself, but when it is taken with other medications, such as oral contraceptives, protease inhibitors and even cholesterol medicine, it may produce adverse effects.

The hypotheses suggest Saint John's Wort may interfere in the metabolic pathways of the fore-mentioned types of medication as well as fifty more. My dilemna begins with not knowing of any pharmaceuticals, whether oral contraceptives or cholesterol lowering medicines which, may produce an observable result in fruit flies (drosophila melanogaster). What I imagined was a two staged experiment where the first stage would be defined by testing a given medication which had been proven in prior research or was most likely to produce a quantitative or qualitative result of sorts. After the presence and magnitude of a result was measured in the first stage, the second stage would incorporate Saint John's Wort and I would observe for any noticeable change in the fruit flies.

My problem is that I do not know enough about the metabolic pathways of fruit flies and the chemicals involved in their functioning. I also do not know about the other 50 medications which the article alluded to. I was wondering if Ask-A-Scientist could help me in terms of locating comprehensive data about the metabolic functionings in a fruit fly, medications which may produce noticeable affects in fruit flies, the metabolic pathways in which those medicines function, and finally medicines which may interfere with Saint John's Wort.

Any information or resources I could use would be immensely appreciated.

I commend you on your idea-but I think you are trying to take on a project that is too big to start. The first thing you have to try is whether or not ANY of these things has an effect on fruit flies. This project sounds like one that would need to be broken down into many separate experiments that would build on each other. I'm sure you don't have the time to invest in that. Why not just try one aspect of it-for example, whether St. John's Wort has any noticeable effect on their phenotype or their behavior.

van hoeck

Your intentions seem logical prima fascia but they probably are not what most scientists would accept to go on with an experiment. When performing this type of research a scientist looks for the proper model system in which to perform the studies s/he desires. In this case since it is drug interaction in many respects a mammalian model seems called for. I know of cross reactions with monoamine oxidase inhibitors and such but the overarching issue is that in such a complex system even if you were performing specific biochemical assays in Drosophila I would be very skeptical of any sort of conclusion extrapolated to the mammalian system since the endocrine and exocrine systems of the two Phyla are so drastically different. I would look for a new project. If you need ideas mail back with the field you are interested in and I can probably come up with some ideas that can be done at your high school.

Peter F.

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