Les Weiner (Former Chair of the Department of Neurology, University of Southern California) gives expert video advice on: How do neurologists repair nerve damage of the brain?; Why are some spinal cord injuries more serious than others?; Is there anything I can do to prevent or decrease my chances of developing a neurological disorder? and more...
How do neurologists repair nerve damage of the brain?
If you damage the neuron, which is the cell body from which the nerve extends... the nerve that's extending is the axon, and that can travel great distances, that axon. Now, when that gets injured, if it's the covering of the axon, like in MS, you can repair that. Now, sometimes it doesn't repair itself, but it could be repaired. The body can make new myelin. However, if the axon is injured, it's not likely it's going to be repairing itself.
How do neurologists repair nerve damage of the spinal cord?
If you damage a nerve it doesn't function or that it functions poorly. So, if I injured my elbow, I might get some numbness in my hand from that nerve. It may be permanent or it may not be. If it is a severe injury, the myelin breaks down - which is the covering, the insulation of the nerve - that can be be repaired. But if the nerve itself, which is the axon, gets injured that doesn't always repair itself. That usually means that you have to repair that in the spinal cord because that's where all the apparatus is for that nerve. So what you want to do is prevent axonal damage. The axonal damage may take months and months to repair itself. It may eventually repair itself if it's not too bad, but again, if it's cut it won't repair itself. So you would have to do something to that nerve to bridge that cut. Those kinds of things are happening, where you are taking something from one place and you put it into another place to replace it.
Why are some spinal cord injuries more serious than others?
In an adult, the lumbar spine from about L1 down has no spinal cord, but it has the roots, it has the nerves that have come from the spinal cord that are going to the lower extremities there in that spinal canal. So, when you have a herniated disc it's the root that gets compressed--you have a fracture it's the root that gets compressed. Whereas if you have a fracture of your neck or a fracture of your thoracic spine you do run the risk of compressing the spinal cord, which is a considerably more difficult thing and winds up with paralysis.
What are "neuroprotective drugs"?
Part of our approach to stroke and to other brain injury types of things, including MS and head injury, is to develop drugs that are what we call "neuroprotective." In other words, to try to develop drugs that will prevent you having an injury or an insult; that the axon doesn't die. In other words, you prevent the axon from dying. And we think the mechanisms for why the axon dies with a head injury or in a stroke are being defined now. There are now a whole bunch of factors which include free radicals, there's what we call "excited toxic effects" where if you overstimulate a nerve it will die. You can't inhibit a nerve to death but you can stimulate it to death. So you want to protect from these kinds of things.
Is there anything I can do to prevent or decrease my chances of developing a neurological disorder?
Well, I think since the number one neurologic disorder is stroke; you certainly can. The causes of stroke are hypertension, diabetes, smoking and arteriosclerosis. All of those are preventable. So you can control those with diet, medicine and exercise. The best way to prevent you from having a stroke is to do those things. So, high cholesterol; you need to watch your diet, you may need to have some medication, etc. It has to be checked. Hypertension is more difficult, because people don't know they have hypertension, but it has to be checked periodically and it has to be controlled. And diabetes - the same way, and smoking is a major cause of stroke. So not smoking is very good. Now, is there a way to prevent getting MS? We don't know of any. Is there a way to prevent getting Alzheimer's - well, we know that the more you do with your brain, you can delay the onset; but it doesn't mean you're not going to get it. Parkinson's, we have no way to know how to prevent its onset. Peripheral nerves, if you're exposed to toxins, if you're diabetic, if you have thyroid problems - those things can be controlled and your peripheral nerves can be dealt with.
How does food affect our nervous system?
Well, there are things that we generally tell our patients no matter what they have. Number one is a good diet. So, a good diet is the same if you have cancer, heart disease, stroke, Alzheimer's, whatever. And that is a reasonably low-fat diet, the carbohydrates are primarily complex, which means fruits and vegetables, right?, and there is a reasonable amount of protein. I might add that, the food supply is under attack right now. So we may have a lot of issues with food that we don't realize. We have to wait and see. The major issues I have with food, which I concern myself, is the use of antibiotics in food and the use of hormones for animals. I think both of those can be troubling and problematic. I'm less concerned with recombinant foods, I think they're probably going to be okay, because most of the DNA is dissolved in your stomach, and there's very little evidence that that's going to be an issue. It might in the long run be healthier that natural foods, but one of the issues is I think that the public should know what they're eating. So I'm a big fan of recombinant DNA food, but there should be a sign on it so the patient, the public can decide whether they want to do it or not.
What vitamins are good for the brain and nervous system?
We usually recommend that they have a vitamin, one vitamin a day. But if they have MS, we ask them to take a little extra Vitamin D3. If we think they are having bony issues, we might ask them to take extra calcium. So the supplements really depend. Clearly if they have pernicious anemia or they have peripheral nerve problems we will give them a little extra folic acid and B12. We certainly will recommend the B vitamins if the patient has a peripheral nerve problem because a number of them are related to the B vitamins. I don't think it is necessary to give patients mega vitamins because there is very little hard evidence that mega vitamins do anything but give you very enriched urine. The sterol-based vitamins actually are toxic if you give too much. So if you have too much Vitamin A, Vitamin A is good or your vision. It's good for your skin but if you have too much of it, it will give you trouble. Too much Vitamin D will give you trouble and too much Vitamin E will give you a central nervous system issue. So you have to use these things in moderation. There is evidence that getting your vitamin supplements from natural foods is particularly useful.
What is the "Human Genome Project", and how does it affect the future of neurology?
The human genome project is going to give us information and allow us to look once we are able to get proper studies in the families and so forth. So there actually tens of millions dollars that have been spent on looking for genetic susceptibility genes in most diseases. Whether it be heart disease, Type 1 Diabetes, Alzheimer's, Parkinson's, MS, etc. So lots of money being spent to say, well, if you're 25 can I determine whether you are gonna get this disease. And if I can, how will I keep you from getting it. Well that's, that's a critical issue. It doesn't do you much good to know that you're gonna get this disease when you're 80 if we can't prevent you from getting the disease. So I think these are issues that have to be worked out. There are financial, the societal and there's alot of difficulties. For instance, if we have somebody who we've identified as having a susceptibility gene when they get to be 50 or 60 to a particular disease, what does that do to their health insurance? What does that do for their life insurance? What does that do to their employer? Employer may not want to hire them, even though they may never get the disease. So these are issues that are not easy to deal with. And they have to be dealt with.
What is the future of neurology?
In neurology we are currently trying to identify people, by genetic means, who are at risk from degenerative diseases. With aging occurring in the sense that populations are getting older and older, everyone, if they live long enough, is going to contract some kind of neurologic problem. It may be a stroke, it may be Parkinson's, it may be Alzheimer's disease, it may be motor neuron disease but quite clearly we need to know how those things are happening. Neurology's future is to carry out a lot of research on that. Neurology will be asking why, who, and perhaps when. We want to know we prevent the damage. Neurology talks about MS, strokes, head injury and neural protective agents. But how do you prevent neurons from dying? We have some ideas of the mechanisms. And finally the best way, for repair and regeneration, is stem cells. We may take a while as lot of things have to be done, but we will probably be testing stem cell therapy with some diseases within the next two or three years. Now that doesn't mean it's treatment, it means it's going to be tested, and my feeling are that's our best chance to make some real differences for people who have problems.