Genetic
Key To Type 2 Diabetes Identified
Altered
Liver Or Pancreas Proteins Root Cause, Study Finds
Mutations
in proteins that turn genes on and off in the pancreas and liver
may make a person more likely to develop late-onset
type 2 diabetes, researchers report in the journal Science.
Late-onset
type 2 diabetes is the result of poor regulation of blood sugar.
Today in the US there is an epidemic of type 2 diabetes,
primarily due to obesity, experts say.
According
to the National Institute of Diabetes and Digestive
and Kidney Diseases (NIDDK), diabetes is a disease
in which blood glucose levels are above normal. People with
diabetes have problems converting food to energy.
After
a meal, food is broken down into a sugar called glucose, which
is carried by the blood to cells throughout the body. Cells
use the hormone insulin, made in the pancreas, to help them
process blood glucose into energy.
Diabetes
Causes Multiple Problems
The NIDDK
states that people develop type 2 diabetes because the cells in the
muscles, liver, and fat do not use insulin properly. Eventually, the
pancreas cannot make enough insulin for the body's needs.
As
a result, the amount of glucose in the blood increases while
the cells are starved of energy. Over the years, high blood
glucose damages nerves and blood vessels, leading to complications
such as heart disease, stroke, blindness, kidney disease, nerve
problems, gum infections, and amputation.
Now
researchers find that alterations in proteins that control the
function of genes in the liver and pancreas also play a major
role in type 2 diabetes.
"We
are making major advances in understanding the genetic problems
that lead to type 2 diabetes," says lead researcher Dr. Duncan
Odom, a postdoctoral fellow at the Whitehead Institute in Cambridge,
Mass., which is affiliated with the Massachusetts Institute
of Technology.
"Diagnosing
and predicting your probability of getting diabetes is going
to be much easier in the next few years," Dr. Odom says.
Recent
studies have shown there are special proteins, called transcription
factors, that regulate how genes are turned and off.
Mutations
in the transcription factors that control the genes that manage
insulin production and blood sugar can cause problems in liver
and pancreatic cells, which in turn can cause type 2 diabetes,
Dr. Odom explains.
Working
with human liver and pancreatic tissue, the researchers studied
which genes these transcription factors affect.
"We
found that one of these transcription factors plays a role in
many liver and pancreatic genes, which was unexpected," Dr.
Odom says.
This
transcription factor, called HNF4-alpha, controls about half
of all the genes needed in forming the pancreas and liver, the
researchers report.
Without
HNF4-alpha, the liver and pancreas cannot function normally,
Dr. Odom says. In addition, mutations in HNF4-alpha make it
more likely for someone to develop type 2 diabetes.
Ongoing
Studies Bring Hope for Treatments
Dr.
Odom says that other research, which is expected to be published
in the coming months, shows that mutations in the genes that
control HNF4-alpha make you much more likely to develop type
2 diabetes if you are obese.
Dr.
Odom believes that "if you can bring HNF4-alpha back to its
normal behavior, you might be able to treat diabetes more effectively."
He speculates it might be possible to develop a medication
that can do just that.
"We
hope that this investigation will give us really good insights
into what causes diabetes and provide additional targets for
therapy," he says.
Dr.
Rohit N. Kulkarni, an investigator at the Joslin Diabetes Center
and an assistant professor of medicine at Harvard Medical School,
says "this new data is really important."
This
study, together with others that show that mutations in these
transcription factors increase the probability of getting type
2 diabetes, indicate these transcription factors are significant
in human disease, Dr. Kulkarni says.
These
factors provide a target that scientists can focus on to treat
diabetes, particularly mutations in HNF4-alpha, which seems
to be the key one, he adds.
Always
consult your physician for more information.
Online
Resources
(Our Organization
is not responsible for the content of Internet sites.)
American
Diabetes Association
Centers
for Disease Control and Prevention (CDC)
HealthierUS.Gov
National
Diabetes Education Program
National
Diabetes Information Clearinghouse
National
Institute of Diabetes & Digestive & Kidney Diseases
National
Insitutes of Health (NIH)
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April 2004
Genetic
Key To Type 2 Diabetes Identified
Diabetes
Causes Multiple Problems
Ongoing
Studies Bring Hope for Treatments
Taking
Aim at Prevention
Online
Resources
Taking Aim
at Prevention
Findings from the
Diabetes Prevention Program (DPP), a major
US study, suggest:
Reach and
Maintain a Reasonable Body Weight
Weight affects health
in many ways. Being overweight can keep a person's body
from making and using insulin properly. It can also cause high
blood pressure.
The DPP
showed that losing even a few pounds can help reduce risk of
developing type 2 diabetes because it helps a person's body
use insulin more effectively. In the DPP, people
who lost between 5 percent and 7 percent of their body weight
significantly reduced their risk of type 2 diabetes.
For example, if a
person weighs 200 pounds, losing only 10 pounds could make a
difference.
Make Wise
Food Choices Most of the Time
What a person eats
has a big impact on health. By making wise food choices, a
person can help control body weight, blood pressure, and
cholesterol.
Take a good look
at the serving sizes of foods. Reduce serving sizes of main
courses (such as meat), desserts, and foods high in fat. Increase
the amount of fruits and vegetables.
Limit fat intake to
about 25 percent of total calories. For example, if food choices
add up to about 2,000 calories a day, try to eat no more than
56 grams of fat. A physician or a registered dietitian can help
figure out how much fat to have. Check food labels for fat content,
too.
A person may
also wish to reduce the number of calories consumed each
day. People in the DPP lifestyle modification
group lowered their daily calorie total by an average of about
450 calories. A physician or registered dietitian can help with
a meal plan that emphasizes weight loss.
Keep a food and exercise
log. When a person meets a goal, she/he should find
a reward that is a nonfood item or activity, like watching
a movie.
Be Physically
Active Every Day
Regular exercise tackles
several risk factors at once. It helps a person lose
weight, keep cholesterol and blood pressure under control, and
helps the body use insulin. People in the DPP
who were physically active for 30 minutes a day five days each
week reduced their risk of type 2 diabetes. Many chose brisk
walking for exercise.
If a person is
not very active, he/she should start slowly, talking with
his/her physician first about what kinds of exercise would
be safe. Make a plan to increase activity level toward the goal
of being active for at least 30 minutes a day most days of the
week.
Here are some ways
to work extra activity into a daily routine:
-
Take the stairs rather than
an elevator or escalator.
-
Park at the far end of the
lot and walk.
-
Get off the bus a few stops
early and walk the rest of the way.
-
Walk or bicycle instead
of drive whenever you can.
Always consult your
physician for a diagnosis.
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