Beta cells, which make insulin in
the human body, do not replicate after the age of 30, indicating that
clinicians may be closer to better treating diabetes. Type
1 diabetes is caused by a loss of beta cells by auto-immunity while type 2 is
due to a relative insufficiency of beta cells. Whether beta cells replicate
after birth has remained an open issue, and is critically important for
designing therapies for diabetes.
By
using radioactive carbon-14 produced by above-ground nuclear
testing in the 1950s and '60s, researchers have determined that the number of
beta cells remains static after age 30.
Lawrence Livermore National Laboratory
scientist Bruce Buchholz, with collaborators from the National Institutes of Health, used
two methods to examine adult human beta cell turnover and longevity.
Using
LLNL's Center for Accelerator Mass Spectrometry, Buchholz measured
the amount of carbon 14 in DNA in beta cells and discovered that after age 30,
the body does not create any new beta cells, thus decreasing the capacity to
produce insulin as a person ages. Carbon 14 atmospheric concentration
levels remained relatively stable until the Cold War, when above-ground nuclear
bomb tests caused a sharp increase, or peak, which decreased slowly after the
end of above-ground testing in 1963. This spike in carbon 14 in the atmosphere
serves as a chronometer of the past 57 years.
Type 2 diabetes (often called adult onset diabetes) is common in older people
whose ability to secrete sufficient insulin to regulate blood sugar
deteriorates as they age and is often due to increased demand in obese people.
"It could be due to loss of
beta cells with age," Buchholz said. "The body doesn't make new ones in
adulthood and there might not be enough cells to control blood sugar."
Source of information here.
2 comments:
Interesting to read this.
Josh
It makes me wonder how much junk is still out there from bomb testing. How much illness have these tests caused ? Far more than we are told I bet !
Eddie
Post a Comment