Monday, November 26, 2012

SeeMyScience: On the Topic of Animal Testing

Earlier this year, I had the opportunity to participate in the “I’m A Scientist, Get me out of here” program, in which students from around Australia ask a variety of scientists questions about every topic imaginable, from what the universe is made of, to what subjects we studied at school. We had some fantastic questions, including one in particular that highlighted one of the most controversial issues in medical science: 

“What do you feel about using animals in experiments and testing experiments on them?”

Animal testing is a loaded topic, and not often spoken about, because scientists often fear the backlash that comes from people who do not understand or approve of what it is we do. As part of this series, I felt it would be appropriate to reproduce my response to this important question, in order to help explain what goes into the development of treatments for some of our most debilitating diseases.

"[This is a question] that is discussed a lot by scientists, particularly in medical research. This is going to be a very long answer, but it is a very big issue! First up, I will be honest: I agree with animal testing in medical research, but not for cosmetics. Now, let’s go in to a bit more detail about why I have these opinions. Let’s start with medical research. I’m going to use drug development as an example, because it’s what I’m familiar with, but this could apply to any disease.

"When a scientist comes up with a new idea for a drug that helps treat cancer, we can’t just take that drug and immediately start using it on people. We don’t know what dose to use, if it will actually cause more harm than not taking the drug, if it will make the cancer get larger, how it interacts with all of our organs. Some new drugs might cause people to have heart failure, or injure their brain, cause birth defects, or just make them feel really sad. In extreme cases, they might even die, so as you can see, we don’t want to go testing things on people straight away. So, where do we start? Hint: It’s not actually with animals!

"Once we’ve done lots of reading about this compound, and figured out how we think it will work, we can do things like run it through a computer simulation. These programs can be quite complex, and give you lots of data about how the body MIGHT react to the drug. This step can rule out lots of drugs, when the computer reminds the scientist that Drug X actually acts on nerve Y in a bad way, so it gets ditched. Even if our drug passes this step, the computer doesn’t know everything about how the human body works (even we don’t!), or how the drug might react with environmental factors. So, after we have gained insight from our computer program, we take it to cell models.

"There are all different kinds of cells we grow in the lab, which can represent all different tissues and diseases. The first thing we do is figure out how much of our drug will cause the cells to die. We then work backwards, using lots of different dilutions to figure out the minimum amount of drug we need to have an effect on the cells. Think of it like making up cordial. We know that straight cordial doesn’t taste very good, but not enough cordial just tastes like water, so we want to get just the right amount to taste good! Once we find this level, we can study the cells to see how they react to the drug. This might be changes in the way they look, what genes they are producing, how well their enzymes are working. We can make sure it is having the effect on the cells we think it is supposed to, or figure out why it is having ones we don’t know about. We do all the same tests in different types of cells, to see what effect it will have on different tissues. This step can take a very long time, and even more drugs never make it past this stage, because they simply do the wrong thing, or are too toxic.

"So, our drug has passed cell culture testing, we think it’s pretty safe, we know how much we need to use, and we’re ready to stick it into a human! NO WAY! We know it’s not killing off the cells in culture, but those are just cells. The body is made up of organs, and blood, and enzymes, all of which can take a drug and change it. This is called bio-metabolism, and some of the products can be quite poisonous. Unfortunately, cell models can only recreate these conditions to a small extent, and we certainly can’t replicate our complex organs in a petri-dish. Without knowing what it will do when it’s taken into our livers, kidneys, brains, etc., wouldn’t you rather have more information? This is where animals come in.

"The only way we can know how a drug will react in complex systems is to place it into a complex system. We want it to be comparable to humans, so we need an animal that has similar genes, organs, and biological processes to us, which can have the same diseases as humans have. In many cases, the closest animals are mice. I’ve already talked a little bit about how mice relate to the human body here.

"Before we work with animals, we have to be very sure that our drug is going to work, and that it is going to be safe. We have to do a lot of math to make sure that we use as few animals as possible, but enough that our results will be meaningful. Even before we see the animals, we have to talk to other scientists, vets, and people from the community, to figure out if this research is going to help people, if we are doing the right thing, a process known as ethics approval. We have to make sure that our animals are going to be under as little stress as possible, that we can reduce stress if we have to, and that we are not going to put the animals in pain. Only after we are very sure of all these things do we ever test on animals.

"When we are running animal trials, we check our animals every day, sometimes twice a day! We make sure they have enough food and water, that they are socialising with other animals, and that they are comfortable. If we ever see that they are in pain, or stressed, we do everything we can to help the animal. Sometimes we have to give them an injection, or take some blood, just like going to the doctor for a blood test. When we give them our new drug, we keep a close eye on them, and if it looks like it’s having a bad effect, or an effect we weren’t expecting, we stop straight away. And at the end of the study, we put the animals to sleep quietly, so that they don’t feel any pain. Some people are lucky, and don’t have to give their animals drugs. Some people give them different food, and Emma from the Organs Zone gets them to run through mazes to check their memory, or listens to them sing to each other!

"The life of the animals we use in research gives us valuable information that can help us improve or save many human lives. It can be very difficult sometimes, and sad, but we treat the animals with respect, and I thank each for the contribution they are making. We do not let anything go to waste, looking at all of the organs and other tissues, and keeping all the parts we don’t use so that other people can look at the same drug or disease without having to do the experiment all over again with new animals.

"I don’t agree with animal testing of cosmetics for reasons that are linked to those I’ve already spoken about above. A new type of hair dye or eye shadow isn’t going to save lives, or really even make them better. We already know so much about the ingredients in products we use on our bodies, that I don’t see why we should use more animals to test them."

I often speak to people, even within my own family, who are against animal testing. Each has their own particular reason, and discussions can become quite heated. Scientists are often told they are evil, amoral, their lives sometimes even threatened, because we have to use these methods in order to complete our research. We can try to reason and explain, but many of us do not, placing it in the 'too hard' basket. I do not enjoy testing on animals, but I know that in doing so, we may be able to help many people in the future.

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