Science Buddies: "Ask an Expert"

hi!

i'm a science buddy mentor, and i would like some of the other mentors' expertise. i am doing a project for chemistry on how capsaicin relieves the pain in joints, and also on how capsaicin might be a future cure for prostate cancer. can someone help me clarify the link between the capsaicin and the vr1? also, how does capsaicin induce apoptosis in prostate cancer cells?

thanks!

Hi Jessica,

this is quite a hot topic of research, so a lot of the knowledge about what capsaicin does is incomplete. One way it is thought to stimulate apoptosis is through direct induction of the p53 tumor suppressor gene (published in the last couple of months). However, capsaicin also affects a variety of other pathways in cancer cells, and that is certainly not the end of the story.

Capsaicin is a vanilloid, which binds to VR1 (a vanilloid receptor), and stimulates nerve cells - VR1 is an ion channel which allows ions to flow into the cell. VR1 is also activated by heat, which is why capsaicin in peppers feels like a burning sensation on the tongue. So you might think it would increase the pain ! However, prolonged exposure to capsaicin appears to desensitize neurons to pain stimuli - possibly because it blocks other ion channels in the cell, or depletes the supply of neurotransmitters. On top of this, capsaicin seems to destroy a molecule called DSP, which itself damages cartilage in joints.

Quite a molecule to come out of chilli peppers !

I hope that will give you enough information to do some further research through a resource like Google scholar: http://scholar.google.com

thanks for the help!

also for my chem project, we have to relate our topic with topics discussed in class. therefore, i am trying to show how the structure of a molecule plays an important role in what it binds with. i want to show that the vr1 binds only to the caspaicin and not the dihydrocaspaicin because of the difference in the molecular structure (capsaicin has a carbon-carbon bond)

http://www.homesteadcollective.org/mpg/ ... cap4.shtml

would that be a correct conclusion? if so, why does the vr1 only bind to the capsaicin?

one more thing...how does capsaicin inhibit the actions of NF kappa-beta?

You should check into this yourself, but I believe that capsaicin prevents NF kappa beta from moving into the nucleus where it normally acts. It's a bit tricky to find online information about thing like this, as it's very new research which is often only available in research journals. However, if you search google for "capsaicin inhibits nf kappa beta" a few things pop up [hint; look for the links to PDFs - they are often freely available as researchers often publish them on their own websites].

Hi Jessica,

Other useful searches could be "VR1 signaling" or "VR1 pathway". this would look for the proteins that the receptor interacts with and switches on or off when the capsaicin activates the receptor. There are a few databases for pathways and signaling which might be worth going to look at eg. Biocarta, KEGG, STKE (googling the names should find the links).

NF-kappa B interacts with a protein called IKappa B (short for inhibitor of NF-kappa B) that prevents it going to the nucleus. Some inhibitors of NF-kappa B act by making more of IKappa B or by making the IKappa B more active. So it might be woth searching "capsaicin and IKappa B"

(also people put the hyphons in between the names in a fairly arbitrary way which makes it harder to search so it might be good to try NF-KB, IKB, I-KB, in all possible combinations)

best of luck,
Caroline

Excuse me for interrupting your conversation. I am looking for a way to apply caspaicin to reduse my increasing psa levels. I think in the tests they made with animals they must have found a way to give it to them without causing stomach cancer or terrible burning mouth. Which parts of the habaneros should i eat, how many of them a day/week and is there trick to get into the prostate without harming my body?

If someone has an idea to solve my problem I would be thankful for a link or an answer.

many thanks in advance and greetings from germany