The Latest In...
RESEARCH ETHICS By Kristie Sullivan, M.P.H.
Simulation Tool Replaces Animals in Diabetes Research
A new computer-based simulation tool for testing type 1 diabetes treatments could soon replace animals in some diabetes research studies. Researchers at the University of Virginia recently developed the method, and now a partnership with the medical research firm the Epsilon Group is expanding its use, giving researchers more human-relevant results. Sixty other academic and industrial research institutions are already using the tool for research purposes.
Sanderson K. Chemistry: It’s not easy being green. Nature. 2011;469:18-20. doi:10.1038/469018a.
Human Skin Cell Model Advances Parkinson’s Disease Research
Scientists at Stanford University have created a new model to study Parkinson’s disease using human skin cells. The laboratory took skin cells from a 60-year-old woman with Parkinson’s disease and grew them into neural cells in a test tube. After 30 days, the cells had grown into groups of neurons that exhibited some of the key characteristics of Parkinson’s disease.
The laboratory—and other laboratories—can now use the model to test whether certain drugs or other compounds (e.g., nutritional supplements) treat the cells’ deficiencies.
Currently, because nonhuman animals do not naturally develop Parkinson’s disease, some experimenters attempt to simulate Parkinson-like symptoms in animals. Some have injected primates’ brains with high levels of the neurotoxin MPTP. As might be expected, however, the symptoms the animals experience do not demonstrate the true form of the human disease. The cellular model avoids the problems of animal experiments and is a huge step forward.
Neurons with symptoms of Parkinson’s disease created from patient’s skin cells. ScienceDaily. Retrieved August 19, 2011, from http://www.sciencedaily.com/releases/2011/03/110303132308.htm.
Hundreds of Thousands of Mice Spared from BOTOX Tests
Hundreds of thousands of mice will be spared from being used in BOTOX tests. This summer, Allergan, Inc. announced a major breakthrough: The Food and Drug Administration (FDA) has approved a fully in-vitro, cell-based assay for use in the stability and potency safety testing of BOTOX.
BOTOX is used for cosmetic purposes but also as a treatment for migraines, muscle stiffness, and other disorders. The new method uses nerve cells to measure the amount of BOTOX needed to block the release of certain neurotransmitters. It offers a more accurate assessment of the potency of each batch of BOTOX than can be achieved by measuring how much of the neurotoxin is needed to kill groups of mice.
Until the FDA approved this new method, Allergan and other companies producing similar products had been using the infamous Lethal Dose 50 (LD50) test, which subjected mice to considerable suffering and results in death by asphyxiation.
NUTRITION by Susan Levin, M.S., R.D., and Kathryn Strong, M.S., R.D.
Avoiding Cow’s Milk May Cut Type 1 Diabetes Risk
Children who are not exposed to cow’s milk proteins during infancy may have less risk of developing type 1 diabetes, according to a report in the American Journal of Clinical Nutrition. In the Trial to Reduce Insulin-dependent diabetes mellitus in the Genetically at Risk (TRIGR) study, women were encouraged to breastfeed. Those who then transitioned their infants to baby formula were given a specially prepared formula in which proteins were broken up so that no intact cow’s milk proteins remained. The full study results are not yet in. However, the TRIGR pilot study, including 230 infants followed until about 10 years of age, showed that those who followed the special feeding plan were 60 percent less likely to develop type 1 diabetes, compared with children who drank regular cow’s milk formula during infancy.
The study adds more support to the long-held theory that cow’s milk proteins trigger the production of antibodies that can destroy a child’s insulin-producing cells.
Knip M, Virtanen SM, Becker D, Dupré J, Krischer JP, Akerblom HK. Early feeding and risk of type 1 diabetes: experiences from the Trial to Reduce Insulin-dependent diabetes mellitus in the Genetically at Risk (TRIGR). Am J Clin Nutr. Published ahead of print Jun 8, 2011.
Vegetarian Diets Fight Heart Disease and Diabetes
Vegetarians have lower blood pressure, slimmer waistlines, and healthier blood sugar, compared with nonvegetarians, according to a study published in Diabetes Care. In 1,011 randomly selected Adventist Health Study 2 participants, the prevalence of metabolic syndrome, a cluster of disease risk factors associated with heart disease and diabetes, was lowest among vegetarians (25.2 percent), followed by semi-vegetarians (37.6 percent), and highest among nonvegetarians (39.7 percent).
Rizzo NS, Sabate J, Jaceldo-Siegl K, Fraser GE. Vegetarian dietary patterns are associated with a lower risk of metabolic syndrome: the Adventist Health Study 2. Diabetes Care. 2011;34:1225-1227.
Calcium Linked to Cardiovascular Disease
Calcium supplements may increase the risk of heart attack and stroke, according to a study published in the British Medical Journal. Researchers followed 16,718 postmenopausal women in the Women’s Health Initiative. They found that a combination of calcium and vitamin D supplements increased heart health risk by 13 to 22 percent. The analysis showed the risk of calcium intake remained with or without vitamin D.
The wisdom of taking calcium supplements has been called into question by previous studies showing that calcium intake from both supplements and dairy products increases the risk of prostate cancer.
Bolland MK, Grey A, Avenell A, Gamble GD, Reid IR. Calcium supplements with or without vitamin D and risk of cardiovascular events: reanalysis of the Women’s Health Initiative limited access dataset and meta-analysis. BMJ. Published ahead of print April 19, 2011. doi:10.1136/bmj.d2040.
World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition, and the Prevention of Cancer: A Global Perspective. American Institute for Cancer Research. Washington, D.C. 1997; p. 322.
Drug-Resistant Bacteria Common in Meat Across Nation
Nearly half of all meat and poultry products in U.S. grocery stores are contaminated with a type of bacteria linked to human disease, according to a study published in Clinical Infectious Diseases. Of those products infected with Staphylococcus aureas, 52 percent had a drug-resistant strain of the bacteria. Researchers collected meat and poultry samples from 80 different brands in 26 retail grocery stores in Chicago; Washington, D.C.; Los Angeles; Fort Lauderdale, Fla.; and Flagstaff, Ariz. The bacteria were most common in turkey samples, followed by pork, chicken, and beef.
Waters AE, Contente-Cuomo T, Buchhagen J, et al. Multidrug-resistant Staphylococcus aureus in US meat and poultry. Clin Infect Dis. Published ahead of print April 15, 2011:doi:10.1093/cid/cir181.