Science Buddies: "Ask an Expert"

Dear Expert,
My name is Minuoja Chandramohan and I am in grade 10. Currently, I am doing research for my next Science Fair Project. My research is mainly on psoriasis. My 1st idea is to choose a plant /mushroom/oil for it's supposed medical properties, to extract from it a compound that I presume of being effective to treat psoriasis or any other skin disease and finally, to test it on a cell line to see if it has any effects on the proliferation of the cells (ex: extracting nimbin from the neam oil). I focused my research on linoleic acid, omega 3 fatty acid, ergosterol, palmitic acid, agaricus bisporus, castor oil and lactarius indigo.I want to know if I can do the experiment on invertebrates' cells since I only have around 2 months left to do my project.

My 2nd area of research is vitamin D insufficiency and psoriasis. The question I asked myself was: '' Is vitamin D₂more effective than vitamin D₃to treat psoriasis? The reasons why I think vitamin D₂might be better than vitamin D₃are that European and North American populations are affected by psoriasis more often than others and in the article '' Role of vitamin D₃ pathway in healthy and diseased skin-facts, contradictions and hypotheses'', it is written: ''In contrast , the serum level of 25OHD₂which derives from nutritional vitamin D₂is commonly very low in the majorty of the European country.'' and also, Agaricus Bisporus contains ergosterol (precursor of vitamine D₂) and this mushroom seems to be effective to treat psoriasis. Do you think I could compare vitamine D3 and D2 to see which one is more effective? Plus, I found an article : ''Direct and indirect induction by 1,25-dihydroxyvitamin D3 of the NOD2/CARD15-defensin beta2 innate immune pathway defective in Crohn disease.'' and the scientists who did the experiment are in Montreal, so I will try to contact them, but I would like to have decided precisely what I want to do before writting them. Would you help me please?

Thank you for your kind support,
Minuoja

Hi Minuoja,

I think these are both interesting ideas that can be pursued well.

For the first project, you can always do whatever experiment with whatever cells, but you do have to be aware of the limitations of your model. In this case, psoriasis is an autoimmune disease, so studying invertebrate cells poses 2 main limitation: 1) that invertebrates have drastically different immune systems in some ways such that autoimmune diseases arise and progress differently, and 2) that invertebrate cells are different, so signaling and growth pathways that are triggered may be different. This is not to say that you can't do it with invertebrate cells -- but there are limitations to your model, and so it may not be applicable to disease directly.

For your second project, I think that's a reasonable hypothesis to test. I can't help you design your own experiment, but I can help you think about model systems that are available to you. What sort of resources (cell lines, human subjects, model organisms, etc) can you obtain? Can you feed anything vitamins? That would be ideal since that would best mimic metabolic conditions which are likely important. Come up with some ideas on your own but also contact the scientists in Montreal to ask what they think could be reasonable.

Dear Aaron Lin,

Thank you for your response and for your wonderful help. But, I have some other questions:

For my 1st project, what kind of cell would be preferable for my experiment? Is there a sort of cell I can get without any aprovals, so more faster? Plus, can I test my product first on invertabrate cells and then on cells that are more alike to psoriasis cells? Also, do you know how much time before we can see the effects on the cells?

For my second project, thank you for your help on model system. Plus, I read an article which supports the case that vitamin D2 should no longer be considered equivalent to vitamin D3 based on differences in their efficacity. Should I still try to prove that vitamin D2 is better in the case of psoriasis or what would be the other way. Also, did my reflection on why vitamin D2 is better than vitamine D3 have sense?

Minuoja

Hi Minuoja,

For the first idea, again, it's up to you based on what you have access to. Ideally you would want to get actual patients with psoriasis to test the extracts on, but that is hard to do and takes lots of time. The next best step would likely be tissue culture of human cells, maybe epithelial skin cells. Ideally you want to attempt to mimic something about the biology of psoriasis to get a reasonable cell line. I'm guessing you work in a lab, if so, ask what sorts of cell lines they have that would be well suited to your work. Like I mentioned before, you can certain work with whatever cells, but be aware that this imposes limitations -- invertebrate cells might not mimic a property true of vertebrate (human cells), so not all of your conclusions will be applicable to humans.

For the second one, it's up to you what you hypothesize. I think your rationale is fine though. Be aware that differences in vitamin D2 and D3 are complex, and it may not just be that D2 or D3 is more effective intrinsically; one alternative possibility is that Europeans experience psoriasis more commonly because genetically they have some mutation which makes them less efficient at processing all vitamin D generally. In other words, don't forget to consider genetic, geographical, and cultural possibilities.

Dear Aaron Lin,
Thank you very much for your reply.
I will consider the differences between vitamin D2 and D3, thank you. I unfortunately don't have access to a lab yet, how would you suggest me to get into a lab which is appropriate for my project?

Thank you!
Minuoja