Walking is beneficial for lots of reasons, and one of its key benefits is
its role in protecting our hearts. Zoltan Arany, MD, PhD, a scientist in
Beth Israel Deaconess Medical Center's Cardiovascular Institute,
investigates the biological mechanisms of cardiac health and heart disease.
His laboratory recently published a study in the medical journal Proceedings of the National Academy of Sciences (PNAS) describing
the importance of a gene called PGC-1alpha, which was found to play a key
role in heart health. Here, Dr. Arany talks about his research — and the
benefits of walking.
Your study looked at a condition called PAD. Can you explain what that is?
PAD stands for peripheral artery disease, which is a condition that
develops when the arteries in the legs become clogged with plaque deposits
and result in reduced blood flow to the limbs. This results in leg pain and
disability. PAD affects 8 million individuals in the U.S. and is the
leading cause of limb amputations.
How is PAD related to cardiac health?
PAD is a warning sign that fatty deposits in the arteries may also be
reducing blood flow to a person's heart or brain, putting him or her at
risk for a heart attack or stroke.
What is angiogenesis and what role does it play in this process?
Angiogenesis is the name for a biological process in which new blood
vessels grow and develop. Our bodies have a terrific built-in "alarm"
system that indicates when our blood circulation is impaired — when, for
example, arteries are clogged with plaque. This "alarm" can trigger the
angiogenic process whenever an injury or artery blockage has left normal
tissue starved for blood.
What did your latest research find?
Last year, I led a research team that discovered that a gene called
PGC-1alpha contributed to "turning on" the angiogenic process. We found
that this gene can sense when levels of oxygen and nutrients are
dangerously low, as would occur when tissue is damaged following cardiac
disease or in PAD In response, PGC-1 alpha then activates the process that
leads to the formation of new blood vessels.
With the current study, we wanted to find out if exercise could activate
this gene. We did this by studying two groups of mice in cages equipped
with electronically monitored running wheels; one group of mice had the
gene, the other didn't. Follow-up tests found that the mice that were
lacking the PGC-1alpha gene failed to grow new blood vessels even though
they exercised. The other group of mice showed robust growth.
So, with this research we have shown that this protein can single-handedly
transform muscle to be capable of greater endurance and increase the blood
vessel content of that muscle. Being able to increase blood vessel density
could help wound healing and even prevent amputations in millions of
patients with diabetes and vascular disease of the limbs, including PAD.
What advice would you give to patients?
Exercise remains one of the most effective interventions for a number of
chronic diseases, including obesity, diabetes, atherosclerosis and
neurodegenerative diseases. PAD is a leading cause of morbidity and the
most common cause of limb amputation in the U.S. and yet even the best
medical therapy available is less effective than simply taking a daily
walk. So, my advice is: Keep moving!
Above content provided by Beth Israel Deaconess Medical Center. For
advice about your medical care, consult your doctor.