I have a joke with one of the guys I work with about us being zombies being pulled irresistibly to the Douglas each morning, never understanding why. It’s not a good joke, or particularly funny, but we take what we can get and it serves as an excellent lead into what I wanted to write about in my first post. This will be a blog about neurobiology and the molecules in our brains that influence our minds and behaviour, so zombies is a good place to start. Obviously.
Now, if you’ve seen a George Romero movie, you’ll know that zombies are all about brains. In fact, some of us Douglas zombies are actually after brains, and we’re not the only ones. Most of working in research at the Douglas study brains. Naturally, this requires actually having brains to study. Our options for studying brains in living humans are quite limited – needless to say, ethics committees frown upon us looking TOO closely at the brains of living subjects.
What we are left with are scans and models. Scans can tell us interesting things about the brain, but the questions you can answer are limited in scope. We can ask about blood flow, which might be an important indicator of brain activity. We can ask how much of a certain chemical is being released by specific brain areas. However, not all of the millions of questions we have about brains and how they work can be answered through scanning.
Sometimes we can take a closer look at things like protein levels, electric signaling, or gene expression by using animal models of human biology. There are many interesting and important questions about brains, genes and behaviour that can be answered using rats, flies, and even slugs. But to paraphrase the statistician George Box, “some models are useful, but all are wrong.” That’s what makes them “models” as opposed to the actual systems we want to work on. Which is why it is so important to get real human brains for efforts like the Douglas Institute Brain Bank.
The ability to analyze brains in great detail is key to understanding mental health, psychiatric diseases and the actual events in the brain that underlie these states. Using our very own brain bank, Douglas Institute researchers like Dr. Gustavo Turecki have gained important insights into depression and suicide by studying differences between the brains of suicide victims and other patients. These studies will contribute to the development of new theories of depression, which will in turn open the door to new treatments for this complex psychiatric disorder.
Unlike depression, some brain disease is relatively easy to understand and even treat. Nobel Prize laureate Eric Kandel refers to these diseases as “neurological disorders,” and can be characterized as being restricted to a certain area of the brain, limited to a small number of systems in that area, and having the same set of symptoms across all patients. A great example is Parkinson’s Disease – we know that cells dying in a specific area of the brain cause the tremors and disturbances in movement (even if we’re not yet sure why they die). We know ways that it can be treated, and although there is no cure as of yet I am highly confident that stem cell research will provide one in my lifetime.
Psychiatric disorders do not follow such simple rules. Depression and schizophrenia, for example, have widely variable symptoms – no two patients are quite alike. They seem to affect wide areas of the brain and many different “sub-systems.” Our hope is that examination of molecular targets, like those I talk about below, will help us to better define the causes of complex diseases and develop better identification of the problems that can give rise to disorders like depression.
Proteins: Proteins are the workhorses of your cells. Enzymes are proteins that make chemical reactions happen in your body. Receptors are proteins that catch signaling molecules and let cells receive information from other cells and their environments. If there’s a job to do in a cell, there’s better than a 99% chance it gets done by a protein. Often we study receptors, and the proteins they use to pass their signals into a cell; but my experiences suggest that you can find at least one neurobiologist that studies any protein that’s ever been discovered in the brain.
Genes: We hear a lot about the “genetic code” and how important it is. What is meant by this is that genes are the pieces of DNA that lay down the codes for cells to make proteins. Genes in DNA are transformed into a sort of middleman called mRNA in a process called gene expression. mRNA is then translated into proteins, which go on to do the real work.
Promoters: In order to be expressed, genes need to be “read” by a set of proteins that make the mRNA. This set of proteins assembles at the start of a gene in a region called the promoter. The cell can control gene expression by controlling the proteins that assemble at a promoter site for a given gene.
In future posts, I will expand on these topics by talking mostly about genes and promoters, the methods we use to study them, and their importance to different aspects of mental health. So I guess you could say that there will be a test on this later. In the meantime, maybe you want to have a closer look at Dr. Turecki’s research, the Brain Bank maintained at the Douglas, or check out this excellent Nature article on the importance of brain banks and some of the scientific advances we can credit to their existence. I hope you’ll even think about donating your own brains to the Douglas zombies – whenever you happen to be done with them, that is. We promise not to eat them.
Posted in General science.Posted on 16 Feb 2009