IUPS/APS Newsroom March 29-April 6
San Diego Convention Center
Hall E Registration Area/Flex Unit
Telephone: 619.525.6228
Contact: Donna Krupa
(703) 967-2751 (cell)
(301) 634-7209 (office, outside IUPS dates)
Pediatric Burn Victims’
Recovery, Diabetes Aided By Fenofibrate; Improved Mitochondrial
Function Increases Glucose Metabolism
Treating insulin resistance directly could cut general trauma illness
San Diego (April 3, 2005) – One of the immediate
serious results of sudden extreme trauma or stress, including burns and even
surgery, is insulin resistance, or diabetes. As a result, healing is
delayed, especially in the case of severe burns, and since the body is
unable to fully use blood sugar for energy, muscle tissue is broken down as
the body scavenges for other possible energy sources.
However, children with
severe flame burns of more than 40% body surface area showed “significantly
improved whole body glucose uptake -- almost to normal levels -- after a
two-week course of treatment with fenofibrate,” according to lead
researcher, Melanie Green Cree at the University of Texas Medical Branch,
Galveston. (The UTMB trauma center last week treated about 20 adult victims,
including several with burns from the British Petroleum refinery after an
explosion that killed at least 15 workers and injured dozens more.)
Cree said trauma in children “seems to cause problems
with fat metabolism, which in turn may cause insulin resistance. This
insulin resistance can be ameliorated with 10-14 days of fenofibrate
treatment, and it may significantly improve morbidity outcomes, healing
rates, and decrease time spent in the intensive care unit.”
Going into the experiment,
“we felt that the fat metabolism in the children may be deranged by their
burns,” Cree said. “We hoped that improving fat metabolism with fenofibrate,
which is traditionally used to lower plasma triglycerides, would improve the
insulin sensitivity. There is conflicting data about the relationship
between glucose and fat metabolism. However, acute burn trauma seriously
affects both glucose and fat metabolism, and our results show that by
increasing cell mitochondrial fat metabolism with fenofibrate (marketed as
Tricor by Abbott Laboratories), glucose metabolism can also be improved,”
Cree reported.
*Paper presentation: “Fenofibrate improves
glucose metabolism in pediatric burns patients,” 12:30 p.m.-3 p.m. Sunday
April 3, Physiology 361.2/board #A317. On view 7:30 a.m. - 4 p.m. Cree
is presenting the research at the 35th Congress of the International Union
of Physiological Sciences in San Diego, March 31 - April 5, 2005.
The entire research team includes: Melanie Green Cree,
Alse Aarsland, David Chinkes, David N. Herndon and Robert R. Wolfe from the
University of Texas Medical Branch and Shriners Hospital for Children,
Galveston.
Surprising 70% of serious burn victims show high
insulin resistance
Working with children at the Shriners Hospital for
Children, Galveston, the team found that when the children were admitted, “a
surprising 70% of children with greater than a 40% total body surface area
flame burns have an insulin sensitivity almost half that of healthy
children. We wanted to understand why this diabetes develops and to see if
medication could reduce it,” Cree said.
The study involved 18 child burn victims ages 4 to 14
years of age who were admitted within four days of injury to the Shriners
tertiary burn center in Galveston. They were studied four days after their
first and third excision and grafting surgeries. The patients were randomly
assigned either to placebo or fenofibrate treatment after the first
procedure. The fenofibrate (FEN) patients received 5mg/kg of fenofibrate
once daily for 11±2 days. Whole body insulin sensitivity was measured with a
clamp technique; stable isotopes of glucose were used to measure liver
glucose release and leg glucose uptake was calculated from arterial
and venous samples. “Both the liver and the muscle in the leg were examined
to try to understand which organs were responsible for the changes in
insulin sensitivity, Cree explained.
After treatment, there was no change in the placebo
group, but whole body glucose uptake during the clamp, the measure of
insulin sensitivity, improved in the FEN group (p = 0.02). Insulin should
prevent glucose release from the liver, but at one week following the burn,
and before treatment, only 60% of release was prevented in either group.
Following treatment, suppression of glucose release by the liver increased
to over 70% of normal in the FEN group, whereas it dropped to 50% in the
placebo group.
Before treatment at one week post-burn, muscle did not
respond much to insulin in terms of glucose uptake. After treatment with
fenofibrate, insulin-stimulated glucose uptake improved in the FEN group,
compared to no improvement in the placebo group.
Mode of operation and next steps, including non-burn
trauma
Results of the clinical experiment “lead to the
conclusion that fenofibrate increases whole body glucose uptake in pediatric
burn trauma patients, and appears to work by enhancing liver and muscle
insulin sensitivity,” Cree said.
“Even greater implications would be to do similar
studies in non-burn trauma patients or in surgical patents,” she added.
“Currently, intensive care units nationwide have been instituting protocols
to keep blood glucose levels normal during recovery. However, if the insulin
resistance itself could be treated, rather than just the high glucose, the
possibility exists for improved outcomes beyond the insulin treatment. This
perhaps could mean faster recoveries and fewer deaths in many situations,”
Cree said.
Already she said the research group is conducting “a
high insulin protocol to tightly control blood glucose levels in the
Shriners youth burn population, to see if the fenofibrate is more or less
efficacious than this traditional high insulin treatment. At the same time,
we are also partially blocking the stress response with a beta-blocker, and
this also seems to improve insulin sensitivity,” Cree noted
Funding and background. Robert Wolfe, professor
in the Department of Surgery and Anesthesia at UTMB, started studying the
hypermetabolic effects of burns at the Shriners hospital for Children,
Boston while at Harvard University. For the past 20 years he has worked with
David Herndon at the Shriners Hospital for Children, Galveston.
This study was supported by an NIH grant.
***
The 35th Congress of the International Union of
Physiological Sciences is in San Diego, March 31 - April 5, 2005. The
Congress (http://www.iups2005.org/)
is organized by the six member societies of the U.S. National Committee of
the IUPS,
the American Physiological Society,
the Society for Neuroscience,
the Microcirculatory Society,
the Society of General Physiologists,
the Biomedical Engineering Society, and
the Society for Integrative and Comparative Biology, under the auspices
of the U.S. National Academy of Sciences.
The IUPS conference, held every four years, runs
concurrently this year with Experimental Biology 2005 at the San Diego
Convention Center.
The American Physiological Society (APS), which is
hosting IUPS, was founded in 1887 to foster basic and applied science, much
of it relating to human health. The Bethesda, MD-based Society has more than
10,000 members and publishes nearly 4,000 articles every year in its 14
peer-reviewed journals. In May, APS received the Presidential Award
for Excellence in Science, Mathematics and Engineering Mentoring (PAESMEM).
***
Editor’s Note: For further information or to
schedule an interview with a member of the research team, please contact
Donna Krupa at the IUPS/APS newsroom @ 619.525.6228 (March 31-April
6), or (703) 967-2751 (cell) or (301) 634-7209 (office), or Stacy Brooks at
240.432.9697 (cell) or 301.634.7253 (office).
A searchable online program for IUPS and EB is at
http://www.faseb.org/meetings/eb2005/call/default.htm