Uterine Stem Cells Used to Treat Diabetes in Mice
|Researchers at NIH have created a mathematical model of what happens when people of varying weights, diets and exercise habits try to change their weight.
Researchers funded by NIH have converted stem cells from the human endometrium into insulin-producing cells and transplanted them into mice to control the animals’ diabetes.
The endometrium, or uterine lining, is a source of adult stem cells. Normally, these cells generate
uterine tissue each month as part of the menstrual cycle. Like other stem cells, however, they can divide to form other kinds of cells.
The study’s findings suggest the possibility that endometrial stem cells could be used to develop
insulin-producing islet cells. These islet cells could then be used to advance the study of islet cell transplantation as a treatment for people with diabetes. If the transplantation of islet cells derived from endometrial cells is perfected,
the study authors write that women with diabetes could provide their own endometrial tissue for such a transplant, sidestepping the chance of rejection posed by tissue from another
person. Endometrial stem cells are readily available and can be collected easily during a simple outpatient procedure. Endometrial tissue
could also be collected after hysterectomy, the surgical removal of the uterus.
“The study findings are encouraging,” said Dr. Louis DePaolo, chief of the Reproductive Sciences
Branch, NICHD, which funded the study. “Research to transplant insulin-producing cells into patients with diabetes could proceed at a much faster pace with a relatively accessible source of donor tissue.”
The authors note that such a treatment would be more useful for people with Type 1 diabetes,
in which no insulin is produced. The treatment
would be less useful for Type 2 diabetes,
in which insulin is usually produced, but in which cells have difficulty using the insulin
that is available. The findings appeared in Molecular Therapy.
Model Predicts Weight with Varying Diet,
Researchers at NIH have created a mathematical
model—and an accompanying online weight simulation tool—of what happens when people of varying weights, diets and exercise habits try to change their weight. The findings challenge the commonly held belief that eating 3,500 fewer calories—or burning them off exercising—will always result in a pound of
Instead, the researchers’ computer
simulations indicate that this assumption overestimates weight loss because it fails to account for how metabolism changes. The computer
simulations show how these metabolic changes can significantly differ among people. Findings were published Aug. 26 in a Lancet issue devoted to obesity.
However, the computer simulation
of metabolism (available at http://bwsimulator.niddk.nih.gov/) is meant as a research tool and not as a weight-loss guide for the public. The computer program can run simulations for changes in calories or exercise that would never be recommended
for healthy weight loss. The researchers hope to use the knowledge gained from developing the model and from clinical trials in people to refine the tool for everyone.
Researchers Discover Genetic Link to Mesothelioma
Scientists have found that individuals who carry a mutation in a gene called BAP1 are susceptible to developing two forms of cancer—mesothelioma and melanoma of the eye.
Additionally, when these individuals are exposed to asbestos or similar mineral fibers, their risk of developing mesothelioma, an aggressive cancer of the lining of the chest and abdomen, may be markedly increased.
The study, published online Aug. 28 in Nature Genetics, describes two U.S. families
with a high incidence of mesothelioma, as well as other cancers, associated
with mutations of the BAP1 gene. The research was funded by the National Cancer Institute and led by scientists at the University of Hawaii Cancer Center, Honolulu, and Fox Chase Cancer Center, Philadelphia.
Mesothelioma tumors are typically associated with asbestos and erionite exposure.
Erionite, a naturally occurring mineral fiber similar to asbestos, is found in rock formations and volcanic ash. Deposits have been located in at least 12 states.
Only a small fraction of individuals exposed to erionite or asbestos actually
develop mesothelioma, one of the deadliest forms of cancer that kills about 3,000 people each year in the United States, with half of those diagnosed dying within 1 year. Additionally, rates of new cases of mesothelioma in parts of the world, including Europe and China, have risen steadily over the past decade.
“This discovery is a first step in understanding the role of the BAP1 gene and its potential utility when screening for mutations in those at high risk,” said Dr. Michele Carbone, study co-leader and director of the University of Hawaii Cancer
Center. “Identifying people at greatest risk for developing mesothelioma, especially those exposed to dangerous levels of asbestos and erionite worldwide, is a task made easier by virtue of this discovery.”