LPI 10th ANNIVERSARY COLLOQUIUM
The American lifespan has increased to an average of 80 years, compared to 50-55 years about 100 years ago. In the U.S., there are now more people over age 85 than people over age 65 just one hundred years ago.
We introduced the concept of "healthspan"the years of our lives filled with good health and vitality. Despite the fact that Americans are living longer, we are not necessarily living well in our later years. A majority of people over the age of 65 years report having one or more chronic health problems. How do we bridge the gap between lifespan and healthspan?
My research team is investigating "age-essential" micronutrients. These are nutrients that decline in the body with age, negatively affecting normal health functions. These compounds also improve the capacity of the body to cope with a variety of oxidative, environmental, and toxicological stresses.
One micronutrient we are currently investigating is L-carnitine. This compound is vital to the function of mitochondria, the "cellular powerhouses" involved in creating energy for cells. As we age, L-carnitine levels decrease in cells. We have done studies on older rats (age 24 months) and fed them acetyl-Lcarnitine (ALCAR), a natural form of L-carnitine that is more bioavailable than L-carnitine itself. These older rats showed significant increases in physical activity, balance, short-term memory, and energy at the cellular level.
However, ALCAR does not improve the body's ability to deal with oxidative stress or improve the body's stress response.
To complement ALCAR, we are also studying alpha-lipoic acid (LA), another micronutrient that helps the body deal with stress. LA can act as an antioxidant and is also used in the mitochondria to convert food nutrients into energy. We have shown that LA administration to older rats results in lower oxidant levels, increased levels of endogenous cellular antioxidants, and improved stress response to chemicals. LA helps turn on the body's built-in stress response systems, which are not as strongly activated as the body ages. Subclinical inflammation and triglycerides were also decreased in older rats fed LA.
Animals fed LA showed only temporary increases of LA in the plasma. A time-release dose may help maintain levels in the body. Cruciferous vegetables (broccoli, kale, collard greens, and Brussels sprouts) are good sources of LA.
Last updated May 2007