Richard Van Noorden
Chris - Now if you are a smoker and you would like to know how to quit the habit, perhaps help is at hand because joining us from Chemistry World is Richard Van Noorden. Hi Richard.
Richard - Hi Chris!
Chris - Youíre going to tell us about these chemical strategies that can help people quit?
Richard - Yes. It all seems so simple, if the nicotine is the demon driving tobacco smoking, then you just give the smokers a nicotine-fix and that will keep their hands off the pack. But itís actually 30 years ago since the first nicotine replacement gum was developed in Sweden, and still, according to US centre for disease control, only 5% of those who try to quit smoking succeed in a year.
Chris - With that gum?
Richard - With that gum.
Chris - Which is not much better than will power is it?
Richard - Yes. But fortunately chemists have some new drugs up their sleeve. Number 1 is marketed in the UK as Champix, which received draft approval from the NHS in March, and a decision is being made about it in July, thatís this month. It works by cutting the pleasure of smoking and reducing the withdrawal symptoms. Itís a bit like nicotine so it binds to the nicotine receptors in the brain and produces dopamine (the pleasure chemical) just like nicotine, but in a slow and long lasting seep, where as nicotine gives you a rush. So, you can use it to alleviate your withdrawal symptoms.
Chris - But donít you get hooked on the Champix then?
Richard - No, as far as Iím aware itís such a small seepage out that itís a bit like the nicotine replacement gum. But the clever thing about this is that although itís a bit like the gum, if you lapse and decide to smoke a cigarette, this drug is already blocking the receptors that nicotine would normally go to, so when you smoke a cigarette you donít get the nicotine rush.
Chris - Didnít this drug originate form the chemicals in a tree in Eastern Europe?
Richard - Yes, the chemical came from the golden rain tree, which has a beautiful name. It has been used since the 1960s by smokers wanting to quit. The chemists changed the structure the molecule slightly, so itís not the same as the molecule youíll find in the tree but like so many chemicals it came from a natural product.
Chris - Like Aspirin. Aspirin came from willow trees. Although the synthetic chemical is very different, the chemical clue was the willow bark. So how do the benefits of Champix compare with Zyban which made the headlines about 10 or 8 years ago, and other things like hypnotism and that kind of stuff?
Richard - Well, theyíre all actually fairly similar. No one has managed to break the ceiling on 30% long-term quit rate. So all of these drugs that you can take are not very successful so far, but one other strategy you could try is a smoking vaccine, which wonít be available yet but I think is incredible.
Chris - How does that work?
Richard - Well, what you do is you take a molecule that looks a bit like nicotine and put a small amount of it in the body and it stimulates antibodies. So when you smoke and nicotine enters your blood stream, the nicotine is swallowed up by the antibodies and forms a big complex. These are too big to cross the blood-brain barrier so the nicotine canít activate the receptors that it normally activates. This is still in clinical trials but it seems promising so far.
Chris - There is a similar technique to treat people who are on cocaine. I think theyíve done the same chemical trick where you take the cocaine and link it to a molecule that makes the immune system react to it and make antibodies against cocaine. I think it works by blunting the delivery of the drug to the nervous system so you donít get that big chemical surge of pleasure, so you forget to associate taking the drug with feeling good, so it breaks up the addictive cycle.
Richard - Yes. The only problem with vaccine is that the antibody concentration may not be large enough to counter a serious relapse for someone who smokes lots of cigarettes.
Chris - A determent smoker...20 cigarettes in the mouth at once!
Richard - Another problem is that you may not be addicted to just nicotine. When you smoke a cigarette, you are probably also addicted to the irritating rush of smoke against your throat, so just taking nicotine replacement gum doesnít stop you wanting that rush of smoke. Sometimes the best anti-smoking strategy is to smoke a cigarette that doesnít have any nicotine in it, and take nicotine replacement gum at the same time. That way you are actually decoupling the two mechanisms, one the nicotine withdrawal symptoms, thatís what the gum is doing, and the other is the pleasure you associate with the smoke and the scent of a cigarette, and thatís what the nicotine free cigarette is providing.
Chris - Well, one problem with smoking is that it makes people look a lot older than they really are. There is actually a medical phenomenon called the smokers face and one of things doctors look for in a patient are lines around the mouth and the obvious complexion of someone who has smoked for a long time. But chemistry has a few things that it can throw at the aging process now, I understand.
Richard - Yes. You might remember earlier in May that there were huge queues outside a Boots store when shoppers were keen to get their hands on this anti-wrinkle cream which Manchester researchers had shown that it actually worked. In fact this anti-wrinkle cream contains pro-retinol as an active ingredient, which is not new or exclusive to this product, itís actually the precursor to vitamin A. There are studies to support that in fact vitamin A increases the amount of collagen under the skin. Collagen is a stringy, fibrous protein that makes the skin supple and elastic. But cosmetics are not drugs, a drug with vitamin A in it, for example a treatment for acne, can contain a lot of active ingredients. But a tightly regulated cosmetic can only change the appearance of your wrinkles because they are not allowed to have enough active ingredients to actually do something to your skin.
Chris - So what sorts of chemicals can you put into your skin to iron-out wrinkles.
Richard - Well, we already mentioned vitamin A, you also have vitamin C which is also a cofactor for collagen production, the alpha-hydroxy acids that you get form fruit are acidic and breakdown dead skin cells to leave the new ones underneath, then there is also antioxidants that prevent skin aging by scavenging up the free-radicals. There are also these peptides which are copies of the precursors for producing collagen proteins. So they are all fairly well understood, itís just the case of how much the cosmetic can have in it. Now whatís quite interesting is that a new branch called the cosmeceuticals industry is trying to create much more bio-active product, more like drugs and less like cosmetics and they are trying to inject fillers into the skin to stimulate the cells to produce more collagen. This is going to be a huge industry if they ever succeed, but we will see.
Chris - Thank you very much Richard. Thatís Richard Van Noorden from Chemistry World, at the Royal Society of Chemistry and you can find out more about what heís been up to on the web at chemistryworld.org.