i on NIH Vodcast
August 28, 2009
“i on NIH” Vodcast Episode #0022
Welcome to “i on NIH”!
Featured in this month's episode are segments about The Alzheimer’s Project, Part two of the African Tutorial, and questions to ask about diabetes.
From the national institutes of health in Bethesda, Maryland – America’s premiere medical research agency – this is "i on NIH"!
Covering health-research topics important to you and the nation, this public service vodcast is your information source from inside all 27 institutes and centers at NIH.
Half an hour, once a month, we’ll show you the excitement of advances and the important information that comes from medical research. And now, here’s your host, Joe Balintfy.
Host: Welcome to episode 22 of "I on NIH." Coming up in this program, we’ll have an interview about the HBO documentary series on Alzheimer’s Disease. Also, part two of our interview about the MedlinePlus African Tutorial. And important reminders and questions to ask for people with type 2 diabetes. But first, the NIH Research Update with Harrison Wein. What do you have for us this month, Harrison?
Harrison: A "depression risk gene" may not add to risk after all. And scientists pinpoint the cells that give you a light touch.
Joe: So the first study is about a gene that was identified back in 2003 as affecting the risk of major depression.
Harrison: Right. Researchers thought they’d found that a gene—called the serotonin transporter gene==that affected the risk of major depression in people who had a number of stressful life events. Serotonin is a chemical messenger that helps brain cells communicate. The most widely prescribed class of medication for treating major depression acts by blocking this transporter. So it all seemed to make sense.
A lot of studies since then have built on this finding. Some researchers even proposed marketing a serotonin transporter gene test to predict your risk for depression.
But here’s the thing, Joe: Scientists who tried to replicate the 2003 study’s findings were getting inconsistent results.
Joe: So what went wrong?
Harrison: Some earlier scientific reviews actually questioned the validity of the gene’s effect on depression. These critics argued that when you have modest gene effects combined with environmental factors, you have to be very careful about interpreting your results.
In the new study, scientists from NIH and 6 universities set out to review the relevant research that’s been done. The team had expertise in epidemiology, biostatistics, genetics and psychiatry. In an approach called a meta-analysis, they re-analyzed data on over 14,000 participants in 14 studies.
They found a strong association between the number of stressful life events and the risk of depression. But variations in the serotonin transporter gene didn’t affect the risk for major depression, alone or in interaction with stressful life events.
Joe: So what does this tell us about depression risk genes?
Harrison: This study really challenges a common approach to studying depression risk. We’re in the early days of understanding how genes and environment interact to increase the risk for depression.
On a broader note, it also shows how important checks and balances are for scientific progress. You often hear about the latest breakthrough on the news, but you should try to put things in perspective. Try asking yourself: is this really the last word?
Joe: Fine advice, Harrison. Now, the other study you mentioned is about touch.
Harrison: Researchers have long suspected that cells in the skin called Merkel cells are responsible for our sense of light touch—how you can feel the softness of silk or the fuzziness of a peach. There are a lot of Merkel cells in our fingertips and lips. Since these cells were discovered over 100 years ago, researchers have thought they probably play some role in our sense of light touch.
In a new study, NIH-funded researchers at the Baylor College of Medicine found a way to create genetically engineered mice that lack Merkel cells throughout most of their skin, but were otherwise normal.
Skin preparations from these mice showed that the type of nerve cell that resolves fine shapes and textures no longer responded to light touch. Other nerve cells, like those that detect hair movements or skin stretching, still responded normally.
So the researchers think they’ve finally shown that Merkel cells are essential to light touch in the skin, although the precise role of the cells still isn’t clear. Still, it’s a touching discovery.
Joe: Very interesting, Harrison. And where can people find out more about these studies?
Harrison: You can read about these and other NIH research studies in "NIH Research Matters." Go to the NIH home page and click the link on the right-hand side, under "In the News" that says, "eColumn: NIH Research Matters" *
Joe: And what’s in this month’s health newsletter?
Harrison: How to improve your attitude about your body. We also have stories about making sure you drink enough water, advice about testing well water and lots of other great stuff.
Joe: And where can people find that?
Harrison: That’s at news-in-health-dot-nih-dot-gov.
Joe: Thank you Harrison.
Harrison: Thank you Joe.
Host: The National Institute on Aging has collaborated with HBO Documentary Films for THE ALZHEIMER'S PROJECT, a multi-platform public health series which takes a look at groundbreaking scientific discoveries and seeks to bring a wider public understanding of Alzheimer's disease research and care.
Host: THE ALZHEIMER'S PROJECT is centered on a four-part documentary film series. To talk about the documentary and the disease, I on NIH talked with Dr. Marcelle Morrison-Bogorad at the National Institute on Aging. Our first question:
Q: What is Alzheimer’s Disease?
Morrison-Bogorad: Alzheimer's is a disease that initially, usually, affects memory, so you have lapses in memory which are much more than a person of your age would be expected to have. So it's not like forgetting where your car in the car park is -- which is a very good thing, because I forget that all the time -- but it's more forgetting why you're in the car park, or the way home, you know? What are keys for? Not just mislaying them but putting them in the refrigerator and forgetting that they're something that you start your car with or open the house with. So but then it progresses. The memory loss progresses so far that eventually in the later stages you don't recognize your spouse.
Q: How many people have Alzheimer’s Disease?
Morrison-Bogorad: So, it's a disease which develops with age, so after the age of 60 or so, the number of people with Alzheimer's doubles every five years. And so the reason it's so worrying for the U.S. population is because we're having such a boom in the elderly. The most people with Alzheimer's are the folk or the highest percentage of people with Alzheimer's are those over the age of 85, and they're the largest growing segment of the population right now. So, the numbers of people who have Alzheimer's are difficult to get completely accurately because it really depends very much on how you stage the disease, but the numbers range from about 2.5 million to 5 million right now. And when you consider the numbers of folk who caregivers, the numbers of families who are affected, it's huge. And when you look at the census data for how many people will be over the age of 65 in the year 2030 or 2050, the number of folk is going to triple with Alzheimer's.
Q: Can you describe NIA’s involvement with The Alzheimer’s Project?
Morrison-Bogorad: So the major film that we were involved in was, of course, the science film, "Momentum in Science", which looks at the research being done by 25 top scientists across the country, and really sort of manages in two hours to condense what was a 400 hour filming session by HBO, where they went to the labs of all these scientists and spent four days with them, almost becoming part of their families. So the science one was the one that we were most involved in, but the other ones were "The Memory Loss Tapes," which details the beginnings of Alzheimer's disease in seven stages. First, the gradual loss of memory, all the way to through to the very final stages. So that is a tremendously touching documentary. And no less touching is the one that Maria Shriver edited called "Grandpa, Do You Know Who I Am?" which is about the experiences of children confronting a grandparent with Alzheimer's disease. Moving. And the fourth one is "Caregivers" and that is looking at how much caregivers do to make the lives of persons suffering from Alzheimer's disease as bearable as it can be.
Q: What kind of responses have you received from the HBO project?
Morrison-Bogorad: Well, we’ve had informal responses. There were a couple of showings here in the Washington area, and the people from the Division of Neuroscience who attended these said that people were so receptive, so moved that several folks left the screening before it edited, before it finished. They couldn't take it. And I think when they were interviewed, a couple of these folks said, "This hit me so hard I now want to take part in a clinical trial." Because that was one of the sort of objectives, because one of the things we need to do, to really get a drug or an intervention that works on Alzheimer's disease is to do clinical trials and to recruit people for these trials as rapidly as possible. So anything that encourages people to take part in clinical trials or clinical research is really very important. And if you look at the HBO.com/Alzheimer's Web site, you can see a lot of comments about the films there. And of the ones I've seen, all of them are positive, except one that said, you know, "I went through this and it was awful to relive it through your series." So I think that just says what a devastating experience it has been and is for caregivers and family who are living with an Alzheimer's victim.
Q: Is there a way to prevent Alzheimer’s disease?
Morrison-Bogorad: We don't know for sure yet, but some of the research, the epidemiology research, suggests that exercise, or keeping your mind active, might help maintain the brain in a sort of state where it can overcome some of the -- at least some of the early pathology that goes on in the brain of a person with early Alzheimer's disease. And so, we know that exercise can help the brain of a healthy elderly person sustain cognition. We don't know if it will really help on the way to Alzheimer's. But the point about all these things that you can do to perhaps prevent Alzheimer's, like exercise, eating right, keeping your blood pressure right, keeping your cholesterol low, is that these are very important for staving off heart disease and also diabetes. So do them anyway, and you might get an added pull up to your brain as well.
Q: What do you think is important to emphasize about the HBO Alzheimer’s Project?
Morrison-Bogorad: Well, I think going back to the science, and why this documentary was developed when there isn't a cure for the disease, and sort of getting back to the "hopeless to hope" question, is that every scientist, and certainly we at NIA who fund most of the federal work on Alzheimer's disease, feel that so much progress has been made in understanding the disease in the past 20 years. So much progress has been made in identifying pathways that are crucial to disease development, and developing drugs and interventions to try to stop these pathways working. We have a tremendous translational program at NIA, which adds to the basic research we fund, to try to look at these pathways and decide on new ways, new interventions to try to develop drugs to target new pathways until the drugs are ready to be hopefully certified by the FDA, so that they can move forward in clinical trials. We also have a big pilot clinical trial program to test a lot of these potential interventions.
Q: What are the goals of clinical trials and do they show promise?
Morrison-Bogorad: So the eventual goal that we might have to go for is combinations of drugs. You know, a combination of a drug to battle amyloid beta protein, one of the major components of the disease; a drug to combat TAU, which is the component of the neurofibrillary tangle, which is the other major component of the disease; drugs to maintain brain cells in a healthy state; drugs to maintain their connections with each other, because if you can't connect to nerve cells then you can't think; and also interventions like exercise, or doing games to stimulate, or having interviews. [laughs] And so all of these are things that we're waiting for big breakthroughs, you know? And I do believe we'll have one, and that's why it's "hopeless to hope". It's not that anything is ready for treatment right now, but there are a lot of very interesting things on the horizon.
Host: For more information about The Alzheimer’s Project and the disease itself, visit www.nia.nih.gov.
Host: In this next interview we continue with Dr. Julia Royall at the National Library of Medicine. Last episode we started the discussion on the MedlinePlus African Tutorials as a teaching tool. Now we continue.
Host: People with type 2 diabetes are faced with a serious disease that can lead to problems such as heart attack, stroke, blindness, kidney failure and lower limb amputations. Infact, heart disease is the number one cause of death for people with diabetes and two out of three people with diabetes die from heart disease or stroke. In this interview, we get important details on type 2 diabetes from Dr. Griffin Rodgers, Director of the National Institute of Diabetes and Digestive and Kidney Diseases. The first question:
Q: What are the diabetes ABCs?
Rodgers: Well, the ABCs of diabetes are three critical items; the A stands for the hemoglobin, the A1c, and that’s a general measure of the average glucose or sugar control in the preceding two to three months. Typically, for most patients, we like that A1C value to be less than seven percent. The B stands for blood pressure, and for most patients with type-II diabetes, a target for that blood pressure should be less than 130/80. C stands for cholesterol, or the so-called bad cholesterol, or LDL cholesterol, we typically like that target to be 90 or less.
Q: Are there questions people should ask their health care team about the diabetes ABCs?
Rodgers: Sure, the critical fact, with the questions, when one has an opportunity to speak to their health care provider is really to ask them, "What are the goals?" and "How am I along the path to achieving those goals?" And that again relates to the A1C, the blood pressure, the cholesterol, the level of intensity of physical activity that one participates in, as well as one’s diet plan.
Q: What are examples of goals that people can set to help them manage their diabetes?
Rodgers: I think it’s very important to pick a realistic goal, and something that one can stick with, and set that goal, write it down, and then work toward that goal. So for example, if your goal is to increase your physical activity, pick an activity that would be realistic for you, such as walking for example, and plan to walk for a certain number of minutes a day. And depending on how active you’ve been before; if you’ve not been very active, one might start with 15 minutes, and then gradually elevate that level of activity. A second goal might be related to, perhaps, changing one’s diet. One might be able to best accomplish that by diminishing the portion sizes that one has, and so considering that first, and then cutting back on calories and the content of fats, for example, might be a realistic goal to consider. The third thing of course, and these aren’t mutually exclusive, is to consider the medications that you’re taking. If you are taking medicines for your diabetes, and if your hemoglobin A1C isn’t in the normal range that your health care provider has set for you, then bring in either your monitor or your log of your blood sugar levels and work with your health care provider to either adjust your medication, or the combination and balance of your medications, your diet, and your physical activity.
Q: How often should people with type 2 diabetes visit their health care team?
Rodgers: In general we think that patients should have at least two visits with their health care provider over the course of the year, at which point the hemoglobin A1 C should be measured. So again, we suggest that for the average patient there should be at least two of these readings. Of course, at this opportunity, on an annual basis, we want to make sure that the blood pressure is checked, the cholesterol and particularly the LDL level is checked. Having an eye examination is critically important, because as I mentioned, eye disease is an important complication. And this also gives the health care provider an opportunity to screen for kidney damage, and testing the blood as well as the urine for evidence of what we call diabetic nephropathy. So those are critical reasons to see a health care provider, and to get these done, certainly on a twice a year basis. Of course, now, if there are complications associated with their disease, the health care provider may want to structure even more frequent visits.
Q: Are there other tests people with type 2 diabetes should ask the health care team about?
Rodgers: Well, in addition to the tests that I’ve mentioned, of course, it’s important to have, at least on an annual basis, this dilated eye examination, so one could look for the presence of diabetic retinopathy. In addition, of course, we’re looking for evidence of kidney damage, so a urine and a blood test to look for so-called diabetic nephropathy is important. Looking for evidence of disease in the foot, and so a foot examination, using fibers to examine the touch and feeling sensation there is a good way to look for nerve damage that might accompany diabetes as ulceration.
Host: More information on managing type 2 diabetes is available in the brochure called "4 Steps to Control Your Diabetes. For Life."
Host: It is available through the National Diabetes Education Program. Call 1-888-693-NDEP or visit www.yourdiabetesinfo.org.
Host: And that’s it for another episode on I on NIH. If you’d like to see or forward individual segments from this program, they’re available on YouTube. Check out the NIHOD channel. Thanks for tuning in and please watch again next time. We’re working on stories about sarcoidosis, PTSD and much more. For I on NIH, I’m Joe Balintfy.
Narrator: "I on NIH" is a public service vodcast from the Department of Health and Human Servives. Produced by NIH News Media Branch, of the Office of the Director, Office of Communications and Public Liaison. Thanks for tuning in. We’ll be back again next month with another episode of "I on NIH."
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