Enzymes linked to diabetes and obesity appear to play key roles in arthritis and leukemia, potentially opening up new avenues for treating these diverse diseases, according to researchers at Washington University School of Medicine in St. Louis.
A STRUCTURE IN CELLS THAT MAKES KEY ENZYMES PREVIOUSLY LINKED TO DIABETES AND OBESITY, ALSO APPEARS TO BE IMPORTANT IN SEEMINGLY UNRELATED DISORDERS, SUCH AS ARTHRITIS AND LEUKEMIA. AND ENDOCRINOLOGY RESEARCHERS AT WASHINGTON UNIVERSITY SCHOOL OF MEDICINE IN ST. LOUIS SAY THE DISCOVERY COULD LEAD TO MORE EFFECTIVE TREATMENTS FOR THOSE PROBLEMS. JIM DRYDEN REPORTS
THE RESEARCHERS WERE WORKING WITH GENETICALLY ENGINEERED MICE THAT DIDNT MAKE CERTAIN ENZYMES, SUCH AS FATTY ACID SYNTHASE. AND THEY FOUND THAT WITHOUT THAT ENZYME, A PART OF THE CELL CALLED THE PEROXISOME WASNT ABLE TO MAKE A SPECIAL TYPE OF LIPID, CALLED AN ETHER LIPID. FIRST AUTHOR IRFAN LODHI IS A WASHINGTON UNIVERSITY ENDOCRINOLOGY RESEARCHER.
(act) :19 o/c in neutrophils
Our study suggests that peroxisomes synthesize a special
class of lipids, called ether lipids. When we inactivated an enzyme called fatty acid synthase, ether lipids were reduced,
and there was a selective and dramatic reduction in neutrophils.
LODHI, AND COLLEAGUE CLAY SEMENKOVICH, WERE SURPRISED THAT NEUTROPHILS WERE AFFECTED.
(act) :05 o/c for neutrophils
The finding, I think, is truly surprising because of its
selectivity for neutrophils.
SEMENKOVICH SAYS NO OTHER CELLS SEEMED TO BE AFFECTED WHEN CELLS IN THE MICE COULDNT MAKE ETHER LIPIDS. AND HE SAYS SINCE THOSE SPECIAL ETHER LIPIDS ARE MADE ONLY IN THE PART OF THE CELL CALLED THE PEROXISOME, THE FINDING PROVIDES A VERY SPECIFIC TARGET FOR BLOCKING ETHER LIPIDS, AND THUS, INFLUENCING THE NUMBER OF NEUTROPHILS IN THE SYSTEM.
(act) :19 o/c benefit health
When you actually, in a targeted way, specifically took
out ether lipids, you could also take out neutrophils. So
this is extending the paradigm of cells make lipids; they
make so in a very channeled and specific way; and by getting
more discreet about where you take out those lipids, you could
have very specific effects that could benefit health.
LIMITING THE POPULATION OF NEUTROPHILS COULD HELP PEOPLE WHO HAVE DISEASES WHERE NEUTROPHILS PLAY A BIG ROLE, SUCH AS RHEUMATOID ARTHRITIS AND LEUKEMIA. AND LODHI SAYS THAT ALTHOUGH LIMITING THE ABILITY OF CELLS TO MAKE ETHER LIPIDS GOT RID OF MATURE NEUTROPHILS, IT DIDNT SEEM TO AFFECT THE PRODUCTION OF THOSE CELLS.
(act) :13 o/c mature neutrophils
It was a highly selective depletion of neutrophils, so
that was responsible for the low white blood cell count.
Differentiation of neutrophils from precursors was not
affected. It was the mature neutrophils.
AND SEMENKOVICH SAYS BY TARGETING ETHER LIPIDS, IT MAY BE POSSIBLE TO CONTROL THE NUMBERS OF NEUTROPHILS AND MAKE IT EASIER TREAT DISEASES LIKE ARTHRITIS AND LEUKEMIA.
(act) :13 o/c as well
So the magic will be to go far enough downstream
to find the perfect target that regulates inflammation
in a way that could treat, for example, leukemias, could treat
chronic inflammation, arthritis and potentially treat
obesity as well.
SEMENKOVICH AND LODHI REPORT THEIR FINDINGS IN THE JOURNAL CELL METABOLISM. IM JIM DRYDEN