Longo, a cell biologist from the University
of Southern California, and Jaime Guevara-Aguirre, an
endocrinologist from Ecuador, conducted a 22-year study that revealed that those
with Laron disease are less
susceptible to cancer and diabetes.
22-year study consisted of Longo and Guevara-Aguirre following a remote
community in the Andes Mountains. Several of the members of this community have
Laron syndrome, which is a deficiency in a gene that stops the body from
utilizing growth hormone. Researchers followed 100 people with Laron syndrome
along with 1,600 relatives of "normal stature."
Guevara-Aguirre found that those with Laron disease did not develop diabetes
over the 22-year period, and only one non-lethal case of cancer was
diagnosed. As far as the 1,600 relatives go, 5 percent developed diabetes in
the same time period while 17 percent were diagnosed with cancer.
growth hormone receptor-deficient people don't get two of the major diseases of
aging," said Longo. "They also have a very low incidence of stroke,
but the number of deaths from stroke is too small to determine whether it's
both groups were exposed to the same genetic and environmental risk factors,
the researchers have a reason to believe that growth hormone activity in adults
who are beyond their growing years can be harmful.
those with Laron syndrome seem to dodge two of humanity's most common diseases,
the lifespan for both groups were about the same. According to the researchers,
the family members with Laron syndrome tend to die from substance abuse and
accidents more than anything else.
all the growth hormone deficient subjects we met appear to be relatively happy
and normal and are known to have normal cognitive function, there are a lot of
strange causes of death, including many that are alcohol-related," said
time, it is not fully understood how growth hormone deficiency protects people
from certain diseases, but Longo found that serum from a subject with Laron
syndrome protects DNA from oxidative mutations and damage, yet also causes the
suicide of severely damaged cells. Those with Laron syndrome have very low insulin
levels as well as low insulin resistance, which could explain why they do not
plan to use the information from this 22-year study to create drugs that are
capable of reducing growth hormone activity, but there are many precautions and
risks that need to be assessed before developing such treatment. For instance,
the treatment would need to show milder effects than drugs used against a
"confirmed disease." Also, it would have to be used for preventative
reduction of growth hormone in adults with high hormone activity in order to
bring it to a normal level, and not to the low levels of those with Laron
syndrome, which could produce even more problems for the individual. In
addition, the treatment would be used only on those with a history of diabetes or
cancer at first.
there are already FDA-approved growth hormone-blocking drugs strictly used for
the treatment of acromegaly, which is closely related to gigantism. Also, mice
studies conducted by John Kopchick have shown that the life of a mouse can be
extended by 40 percent when the growth hormone is blocked. Kopchick also found
that growth factor deficiency led to reduced tumor risk in mice.
to Longo, drug treatments are not the only way to reduce growth hormone
activity. Natural methods like restricting calories and proteins in the diet
seem to have a similar effect. But the study also added that restricting
specific nutrients could have adverse effects as well, causing more harm than
Guevara-Aguirre now plan to seek approval for a clinical trial to test
preventative growth hormone-reducing drugs on patients undergoing chemotherapy,
since mouse models and human cells have been protected against chemical damage
in previous studies. They hope this can lead to effective drugs that can
prevent cancer and diabetes, and help others live similarly to the way those
with Laron syndrome do in the Andes Mountains - disease free.
the dream of every administration, anywhere in the world," said Longo.
"You live a long healthy life, and then you drop dead."
This study was published in Science Translational Medicine.
quote: If only the rest of the population did 5% of the exercise.