葫芦娃视频

Your chronological age might not yield the answer. CU-葫芦娃视频 researchers are studying ways to reverse arterial aging, linked to the leading cause of mortality in America.听I spent 12 weeks in a clinical study of a carbohydrate听that might reverse arterial aging. Here鈥檚 what I learned鈥�

The treadmill spins faster and tilts higher. What was a light, flat jog is now a hard uphill run. My legs are faltering. Arms are flailing. It鈥檚 not flattering.

My breathing veers toward gasping. But my nose is pinched closed, and each breath is taken and measured via a tube in my mouth. A spiderweb of wires stuck on my torso tracks my heart rate, which hits 196 beats per minute.

This鈥攂oth mind and body concur鈥攊s a fine time to stop.

I am completing the second of two VO2 max tests, which measure maximal aerobic capacity. I鈥檇 done the first test in spring, the second after 12 weeks of a 葫芦娃视频 research study to determine the arterial benefits of a natural carbohydrate听called trehalose.

I am 52 years old. I get regular invitations from the AARP, and my arteries are stiffer and do not dilate as well as they did at age 22. That stiffness matters, because declining arterial health鈥攐ften caused by endothelial dysfunction鈥攊s linked to cardiovascular disease.

Heart disease causes about one in four deaths annually and is the leading cause of mortality in the nation, the U.S. Centers for Disease Control and Prevention reports. Most heart-disease deaths occur in people over 65, a demographic group that is expected to balloon.

In 2010, 40 million Americans were 65 or older. By 2050, that number is expected to be 89 million. The portion of the U.S. population over 65 is expected to rise from 13 percent to 20 percent, reports the U.S. Department of Health and Human Services.

Let鈥檚 face it. Despite our best efforts, some people are not going to exercise or improve their diet, but they may benefit from alternative strategies.

Lowering heart-disease risk in older people could save health-care resources and improve quality of life for millions.

Those entering middle age need not abandon all hope. Older adults can slow the decline of arterial function with good lifestyle choices: exercising more, losing weight, eating well and ingesting less salt.

But habits persist. People forgo exercise and good nutrition regardless of how persuasively public-health campaigns preach. That鈥檚 one reason researchers, including those at CU-葫芦娃视频, investigate alternatives.

How to maintain arterial health?

罢丑别听听at CU-葫芦娃视频 researches a host of ways to slow or reverse arterial aging in middle-aged and older adults. The lab, directed by Douglas R. Seals, professor of distinction of integrative physiology, conducts clinical tests on the arterial benefits of Vitamin D, oral sodium nitrite, curcumin (the active ingredient in turmeric) and trehalose.

Seals emphasizes the benefits and limitations of good lifestyle choices. 鈥淟et鈥檚 face it. Despite our best efforts, some people are not going to exercise or improve their diet, but they may benefit from alternative strategies.鈥�

I figure I need no 鈥渁lternative strategy.鈥澨齀 spend more than 200 hours a year vigorously exercising, and I鈥檓 vegan. I have low cholesterol numbers, low risk for heart disease, and probably low risk for aneurysm and stroke, which claimed my dad and granddad.

I volunteered to participate in the trehalose study for two reasons: curiosity and a desire to support science that could help people.

Trehalose is a nutraceutical: a food or non-synthetic food supplement with purported health benefits. The carbohydrate, found in mushrooms and other sources, has a unique chemical structure and might听improve arterial health.

Studies in mice have shown that trehalose can protect against age-related neurological diseases and extend longevity.听听

In addition, the Integrative Physiology of Aging Laboratory has shown that in old mice, trehalose restores arterial elasticity and endothelial function to levels observed in young animals.听

This was the first step in the translational-research approach employed by the laboratory, in which compelling therapies are first studied in animals and then examined in humans.

Good arterial health depends on proper functioning of the lining of blood-vessel walls鈥攖he endothelium. Good endothelial function relies in part on the ability of cells to eliminate damaged proteins and dysfunctional mitochondria. This shedding of damaged cellular components is called autophagy.

鈥淚t鈥檚 a kind of a way for cells to clean house,鈥� says Rachelle Kaplon, a doctoral candidate in integrative physiology and the principal investigator of the trehalose study.

Trehalose is a nutraceutical: a food or non-synthetic food supplement with purported health benefits. The carbohydrate, found in mushrooms and other sources, has a unique chemical structure and may improve arterial health.

With age, autophagy becomes less efficient. That decline contributes to age-related vascular oxidative stress and inflammation, precursors to heart diseases including stroke, peripheral artery disease and atherosclerosis. Volunteers are still participating in the trehalose study, which should be completed by next spring.

Research participants like me consume 100 grams of carbohydrate听dissolved in water each day for 12 weeks. This is a double-blind experiment, so neither Kaplon nor participants knows whether the carbohydrate听being ingested is trehalose or maltose, the placebo.

Kaplon does note that trehalose is a relatively easy pill to swallow. 鈥淯nlike a lot of pharmaceutical drugs that might be able to target this process, 听trehalose is a very safe compound used widely in food manufacturing.鈥�

Weight gain is possible, of course. Research subjects are asked to keep their weight and physical activity stable. That means reducing the number of calories you get from regular sources

The Integrative Physiology of Aging Lab hopes its work may help aging adults maintain healthy lifestyles as long as possible. Kaplon calls this a 鈥渕eaningful increase in lifespan,鈥� one with, say, less time in a nursing home and more physical and cognitive ability into older adulthood.

Subjects: healthy but not off the charts

Before joining the experiment, which is being conducted on people over 50, I had to qualify. I passed a cognitive-function test (correctly answering questions like 鈥渨hat year is it?鈥� and demonstrating a functioning short-term memory).

Eligible volunteers must show some level of vascular dysfunction. Despite my efforts to live well, I lack the arteries of a 22-year-old. That might seem predictable. It isn鈥檛.

Researchers also tested my blood pressure, blood composition and physical fitness. From an arterial function perspective, I had to be healthy, but not too healthy.

Eligible volunteers must show some level of vascular dysfunction. Despite my efforts to live well, I lack the arteries of a 22-year-old. That might seem predictable. It isn鈥檛.

More than 100 people over 50 have signed the consent form for the study, but about a quarter of them show no age-associated vascular dysfunction, Kaplon says.

鈥淲e get people who are really physically active or just have a pretty healthy lifestyle who have really well-preserved vascular function鈥濃�攚ith the arteries of 20-year-olds.

Those candidates do not qualify for the experiment.

鈥淲e don鈥檛 feel it鈥檚 ethical to put people through all of the testing if there鈥檚 nothing that we can do to improve their blood-vessel function,鈥� Kaplon observes.

But there is unpredictable variation. The lab sees sedentary, sometimes-overweight candidates who have 鈥済reat vascular function.鈥�

And there are very active people like me who have diminished vascular function. Genetics, stress, sleep patterns and other factors can take a toll.

Tests, carbs听and more tests

Once a subject qualifies for the study, researchers take 鈥渂aseline鈥� measurements of maximal oxygen uptake and arterial function. These tests are repeated at the end of the 12-week period, to determine what change, if any, researchers see in vascular function and aerobic fitness.

The testing is conducted in CU-葫芦娃视频鈥檚 Clinical Translational Research Center, the only such center in the country not on a medical campus.

The VO2 max tests, perhaps more dramatic than the arterial function tests, showed my maximal oxygen intake to be 50 milliliters per kilogram of body weight per minute at the beginning of the study.

A VO2 max of 50 is good听for a Baby Boomer. A fifty-something with a VO2 max of 35 is average, and one scoring less than 26 is considered to have 鈥渧ery poor鈥� uptake.

By contrast, in their peak, Olympic marathon champ and 葫芦娃视频 running legend Frank Shorter recorded a VO2 max of 71, and Tour de France champ Greg LeMond clocked a 92.5.

The arterial function tests yielded more-precise data. Generally, greater dilation indicates healthier vasculature.

With my arms in inflatable cuffs, researchers test the function of the endothelial layer of arteries by infusing four substances: acetylcholine, which increases arterial dilation; sodium nitroprusside, another substance that increases dilation; a nitric oxide synthase inhibitor, a drug that blocks vasodilation; and vitamin C, an antioxidant.

Acetylcholine acts on the endothelial layer of arteries to cause vasodilation (primarily through endothelial release of nitric oxide). As such, this is a measure of endothelium-dependent dilation, Kaplon notes.

At the beginning of the study, my arteries responded minimally to acetylcholine: My response was about 16 percent of what is seen in people鈥檚 20s.

If researchers see impaired dilation鈥攕uch as mine鈥攊t could reflect one of two things. It could be that the signals that need to be sent from the endothelium aren鈥檛 being sent. Or it could be that the smooth muscle cells aren鈥檛 functioning well and aren鈥檛 responding to the signals they鈥檙e receiving.

My smooth muscle cells performed well, the tests showed.

The tests showed that acetylcholine injected with vitamin C evoked much more dilation. This indicates that my reduced vascular dilation is due in part to oxidative stress鈥攚hich may further indicate that I have faltering autophagy.

Bummer.

At the time of the study, I did not know whether I was in the placebo (control) group or the trehalose (experimental) group. Now, I know which group I was in but can鈥檛 divulge it publicly. Kaplon must remain 鈥渂linded鈥� as she completes her analysis of the results.

Meanwhile, it is heartening to observe the work of Kaplon, Seals and their colleagues.

I know full well the bell tolls for me. Research like this might delay its toll on thee.

For more information about the Integrative Physiology of Aging Laboratory, click听.

Clint Talbott听is director of communications and external relations for the College of Arts and Sciences.