|
Researchers create pigs that produce
heart-healthy omega-3 fatty acids
COLUMBIA, MISSOURI - March 26, 2006 - Researchers report
they have created pigs that produce omega-3 fatty acids, which are
known to improve heart function and help reduce the risks for heart
disease, representing the first cloned transgenic livestock in the
world that can make the beneficial compound. The research could
be a boost to both farmers and health-conscious consumers seeking
an alternative and safer source of omega-3 fatty acids. Currently,
the only way for humans to realize the benefits of omega-3 fatty
acids is by taking dietary supplements or by eating certain types
of fish that may also contain high levels of mercury.
The results, which are being published in the April 2006 Nature
Biotechnology, are the work of a team assembled by Yifan Dai,
MD, PhD, of the University of Pittsburgh School of Medicine that
includes researchers from Randy Prather, PhD's group at the University
of Missouri-Columbia (MU) National Swine Resource and Research Center,
the laboratory of Jing X. Kang, MD, PhD, at Massachusetts General
Hospital (MGH), and the laboratories of Dai and Rhobert Evans, PhD,
at Pittsburgh.
To stimulate production of omega-3 fatty acids in pigs, a team
led by Dai transferred a gene known as fat-1 to pig primary
fetal fibroblasts, the cells that give rise to connective tissue.
Prather's group then created the transgenic pigs from these cells
using a method called nuclear transfer cloning. The transgenic pig
tissues were then analyzed for omega-3 fatty acids in Kang's lab
at MGH and by Dai and Evans at Pitt. The fat-1 gene is responsible
for creating an enzyme that converts less desirable but more abundant
omega-6 fatty acids in the animals to omega-3 fatty acids. The results
could lead to a better understanding of cardiovascular function
not only in pigs but in humans as well.
"Pigs and humans have a similar physiology," said Prather,
distinguished professor of reproductive biology in MU's College
of Agriculture, Food and Natural Resources and a corresponding author
with Dai. "We could use these animals as a model to see what
happens to heart health if we increase the omega-3 levels in the
body. It could allow us to see how that helps cardiovascular function.
If these animals are put into the food chain, there could be other
potential benefits. First, the pigs could have better cardiovascular
function and therefore live longer, which would limit livestock
loss for farmers. Second, they could be healthier animals for human
consumption."
"While fish, especially salmon and tuna, is one of the best
food sources of omega-3 fatty acids, we have been warned to limit
consumption because of high mercury levels. These animals could
represent an alternative source as well as be an ideal model for
studying cardiovascular disease and autoimmune disorders,"
said Dai, an associate professor of surgery at the University of
Pittsburgh School of Medicine's Thomas E. Starzl Transplantation
Institute.
"Livestock with a health ratio of omega-3 to omega-6 fatty
acids may be a promising way to re-balance the modern diet without
relying solely on diminishing fish supplies or supplements,"
Kang said.
The transgenic pigs were created using technology developed by
Kang of MGH, an associate professor of medicine at Harvard Medical
School and co-lead author of the current report with MU's Liangxue
Lai, PhD. Kang's group created the first omega-3 rich mammals (mice)
and published
that work in Nature in 2004. Because of this earlier
study, Dai initiated the collaboration with the aim of creating
cloned transgenic pigs capable of making omega-3 fatty acids.
The production of these pigs will now provide researchers with
opportunities to conduct studies not previously possible. For example,
researchers in MU's College of Veterinary Medicine department of
biomedical sciences now plan to study the omega-3 pigs. Harold Laughlin,
PhD, department chair, uses pigs to study the cardiovascular benefits
of exercise because a pig's cardiovascular system is similar to
a human's. Now he plans to incorporate these unique pigs into his
research to determine how higher omega-3 levels and exercise could
affect the cardiovascular system.
In addition to Prather and Lai at MU, Kang at MGH, and Dai and
Evans at Pitt, other authors include Rongfeng Li, PhD, Hwan Yul
Yong, PhD, Yanhong Ho, PhD, David M. Wax, Clifton N. Murphy, PhD,
DVM, August Rieke, M.S., Melissa Samuel, Michael L. Lihville, DVM,
and Scott W. Korte, DVM, all of MU; Jingdong Wang of MGH and Harvard
Medical School; and William T. Witt, MS, and Thomas E. Starzl, MD,
PhD, of the University of Pittsburgh. Their research was supported
by the National Institutes of Health, the American Cancer Society
and an unrestricted gift to the Thomas E. Starzl Transplantation
Institute at the University of Pittsburgh from the Robert E. Eberly
Program for Transplant Innovation.
Media Contacts: Sue
McGreevey, MGH Public Affairs
Christian Basi, University
of Missouri
Lisa Rossi, University of
Pittsburgh
Physician Referral Service: 1-800-388-4644
Information about Clinical Trials
|
|
 |
