The Latest In...
RESEARCH ETHICS By Kristie Sullivan, M.P.H.
NONANIMAL RESEARCH METHODS
EPA’s ToxCast Program Expands Nonanimal Testing
Since 2008, the Environmental Protection Agency’s ToxCast program has predicted the toxicity of thousands of substances. The program uses computer modeling and in vitro methods instead of animal testing to screen pesticides, food additives, drugs not on the market, and other products. The aim of ToxCast is to develop cell-based tests to replace current tests that use hundreds or thousands of animals.
EPA is now expanding the program by awarding a $27 million contract to the company Expression Analysis to test more than 12,000 chemicals found in thousands of human fluid samples. The company is developing gene-based biomarkers—signals that a chemical has had an effect on an organism’s cells and tissues—which will make toxicity testing more human-relevant.
EPA Awards $27 Million Contract to EA for Expansion of ToxCast’s Genomic Data. NCTechNews. Accessed Aug. 27, 2012. Available at: http://nctechnews.com/2012/07/24/environmental-green-tech/epa-awards-27-million-contract-to-ea-for-expansion-of-toxcasts-genomic-data/7574/
Human Tissue Chips to Predict Drug Safety
3-D chips from living human tissues will soon predict the safety of drugs faster and more cost-effectively than animal tests. The chips will model human organs such as the lung, liver, and heart. Ranging in size from a quarter to a house key, the chips will be tested with compounds known to be safe or toxic in humans. Disease and tissue models will include lung fibrosis, cardiac tumors, osteoarthritis, kidney disease, neurodevelopmental toxicity, and muscle, intestinal, and neurovascular tissue. The “Tissue Chip for Drug Screening” initiative is funded by the newly created National Institutes of Health National Center for Advancing Translational Sciences, in collaboration with the Defense Advanced Research Projects Agency and U.S. Food and Drug Administration.
National Institutes of Health. NIH funds development of tissue chips to help predict drug safety. NIH News. Accessed Aug. 28, 2012. Available at http://www.nih.gov/news/health/jul2012/ncats-24.htm
Large-Scale Prediction and Testing of Drug Side Effects
A new study published in the journal Nature used computer modeling to predict the adverse reactions of 656 drugs. Of the 1,042 predictions tested, approximately half were confirmed in human cells. This method could be used to eliminate drugs most likely to fail before they go to clinical trial. Severe “off-target” reactions to drugs not predicted by animal experiments are the main reason drugs fail either in clinical trials or once on the market.
Lounkine E, Keiser MJ, Whitebread S, et al. Large-scale prediction and testing of drug activity on side-effect targets. Nature. 2012; 486:361-367.
NUTRITION by Susan Levin, M.S., R.D.
“Low-Carb” Diets Increase Heart Disease Risk
Low-carbohydrate diets can lead to weight gain and heightened risk of heart disease, according to a new study in Sweden. As part of an effort to reduce heart disease risk in the 1980s, more than 140,000 individuals were encouraged to decrease their fat intake. They did so, and their cholesterol levels fell. However, in the early 2000s, the low-carbohydrate diet fad led many of these individuals to forgo healthful carbohydrates and eat fattier foods instead. The results were higher cholesterol levels and overall increased heart disease risk.
Johansson I, Nilsson L, Stegmayr B, Boman K, Hallmans G, Winkvist A. Associations among 25-year trends in diet, cholesterol and BMI from 140,000 observations in men and women in Northern Sweden. Nutr J. 2012;11:40. E-pub ahead of print.
Nearly a Quarter of U.S. Teens Have Diabetes or Prediabetes
The prevalence of diabetes and prediabetes among teens is up from 9 percent in 1999-2000 to 23 percent in 2007-2008, according to a new study published in Pediatrics. Researchers from the Centers for Disease Control and Prevention reviewed data to find that teenagers, about 34 percent of whom are overweight or obese, are at increased risk for several cardiovascular disease risk factors such as high blood pressure, abnormal cholesterol levels, and diabetes. Prevalence of at least one cardiovascular disease risk factor was at 37, 49, and 61 percent for normal weight, overweight, and obese teens, respectively.
May AL, Kuklina EV, Yoon PW. Prevalence of cardiovascular disease risk factors among US adolescents, 1999-2008. Pediatrics. 2012;129:1035-1041.
Soy Products Protect Women from Breast Cancer Recurrence
A report in the July edition of the American Journal of Clinical Nutrition shows that women previously diagnosed with breast cancer have less risk of cancer recurrence if they consume soy products. The report combined the results of three prior studies, including a total of 9,514 women. Those who consumed the most soy products were 25 percent less likely to have their cancer return, compared with those who avoided soy products.
Nechuta SJ, Caan BJ, Chen WY, et al. Soy food intake after diagnosis of breast cancer and survival: an in-depth analysis of combined evidence from cohort studies of US and Chinese women. Am J Clin Nutr. 2012;96:123-132.
Low-Fat, Plant-Filled Diet Reduces Weight and Symptoms of Menopause
Women who were encouraged to eat a low-fat diet with more fruits, vegetables, and whole grains lost weight and reduced hot flashes and night sweats, according a new study in the journal Menopause. Researchers placed 17,473 postmenopausal women from the Women’s Health Initiative Dietary Modification trial in either a group supported to make specific dietary changes or a control group that received minimal nutrition information and no group support. Women who adopted the low-fat diet were three times as likely to lose weight, compared with the control group.
Kroenke CH, Caan BJ, Stefanick ML, et al. Effects of a dietary intervention and weight change on vasomotor symptoms in the Women’s Health Initiative. Menopause. 2012;19(9):980-988.