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RESEARCH ETHICS By Kristie Sullivan, M.P.H., and Nancy Beck, Ph.D.
ALTERNATIVES TO ANIMAL RESEARCH
Science Embraces Animal-Free Cell Cultures
Many research studies now focus on cells rather than the whole body. But scientists have expressed concerns that growing cell lines with animal-derived ingredients can lead to a number of problems, including potential contamination with bacteria, viruses, and allergens. As a result, many biotechnology supply providers now offer animal-free products. SAFC Biosciences recently made its Lenexa, Kan., manufacturing site entirely animal-component free, citing increased customer demand and tightening regulations. PCRM pioneered the use of animal-free diagnostic assays when it developed the first insulin assay manufactured in cell culture without the use of fetal calf serum, which is derived from prenatal calves whose mothers are slaughtered while pregnant.
Vaccine Testing Becomes More Relevant to Humans
Researchers have designed a new nonanimal system to test vaccines for potency. Touted as a “human immune system in a tube,” the MIMIC system could replace animals in several safety and efficacy tests. In a case study with the tetanus vaccine, scientists at VaxDesign Corp. in Orlando, Fla., found that the MIMIC system accurately modeled the human immune response when compared with study volunteers. The results are published in the June issue of Biologicals. The scientific relevance of the system is reflected in its growing user base. According to VaxDesign’s Web site, the U.S. Department of Defense is using MIMIC to assess potential plague vaccines.
Byers AM, Tapia TM, Sassano ER, Wittman V. In vitro antibody response to tetanus in the MIMIC system is a representative measure of vaccine immunogenicity. Biologicals. 2009;37:148-151.
NONANIMAL REGULATORY TESTING
EU Cosmetics Testing Ban Now in Place
The European Union Cosmetics Directive testing ban took effect on March 11, banning the use of animals in testing cosmetic ingredients for short-term tests such as for eye or skin irritation. It also prohibits the sale of cosmetics containing animal-tested ingredients. The use of animals in long-term testing, such as carcinogenicity testing, is still allowed but will be prohibited in 2013.
New International Testing Guidelines Will Save Animals
New chemical testing procedures adopted by a key international organization will save thousands of animals a year from painful death. At a recent meeting in Paris, the Organisation for Economic Cooperation and Development (OECD) approved four nonanimal testing methods for severe eye irritation and other tests. The OECD also approved a new acute inhalation toxicity test that will use 55 to 85 percent fewer animals. Over the next few years, the OECD’s Test Guidelines Programme will work to approve nine more nonanimal methods for skin irritation, carcinogenicity screening, and other tests. The OECD is the international authority on chemical testing guidelines; its guidelines are accepted by regulatory authorities of all member countries, including the United States, Canada, and the European Union.
NUTRITION By Susan Levin, M.S., R.D., and Kathryn Strong, M.S., R.D.
Meat and Dairy Products Harm Sperm Quality
Men who eat more processed meat and full-fat dairy products may have poorer quality sperm than those who avoid animal fat and consume more fruits and vegetables. In a study of 61 Spanish men, normal sperm quality was associated with higher intake of carbohydrates, fiber, folate, vitamin C, and lycopene and lower intake of protein and total fat. The study suggests that in addition to its numerous other benefits, a healthful diet may also improve fertility.
Mendiola J, Torres-Cantero AM, Moreno-Grau JM, et al. Food intake and its relationship with semen quality: a case-control study. Fertil Steril. 2009;91:812-818.
Soy Decreases Cancer Risk for Men and Women
Soy intake reduces the risk of prostate cancer and breast cancer, according to two new papers in the American Journal of Clinical Nutrition. An analysis of 14 studies showed that increased intake of soy resulted in a 26 percent reduction in prostate cancer risk. Researchers found a 30 percent risk reduction with consumption of nonfermented soy products such as soymilk and tofu.
The second paper, which studied almost 2,400 Asian-American women, found that those with the highest intakes of soy and vegetables had a decreased risk of breast cancer. Those with the highest intakes of meat and starches had a twofold increased risk. Researchers concluded that lower intakes of meat and starches and higher intakes of legumes and vegetables protect against breast cancer in Asian-American women.
Yan L, Spitznagel EL. Soy consumption and prostate cancer risk in men: a revisit of a meta-analysis. Am J Clin Nutr. 2009;89:1155-1163.
Wu AH, Yu MC, Tseng C, Stanczyk FZ, Pike MC. Dietary patterns and breast cancer risk in Asian-American women. Am J Clin Nutr. 2009;89:1145-1154.
Fish Oils Offer No Heart Benefit
Omega-3 fatty acids, often taken in the form of fish oil, have no heart-health benefit, according to a report presented at the American College of Cardiology’s annual meeting. Among nearly 4,000 heart attack patients, no difference was seen between those who consumed omega-3 supplements and those who took placebo pills.
The conclusions are similar to those of a 2006 review of 89 randomized control trials and cohort studies, which showed no benefit of omega-3 intake on total mortality, cardiovascular events, or cancer.
Senges J. Omega-3 fatty acids on top of modern therapy after acute myocardial infarction (OMEGA). Report presented at: American College of Cardiology Annual Meeting; March 30, 2009: Orlando, FL.
Hooper L, Thompson RL, Harrison RA, et al. Risks and benefits of omega-3 fats for mortality, cardiovascular disease, and cancer: systematic review. BMJ. 2006;332:752-760.
Cognitive Decline Associated with Fat Intake
Fatty foods eaten during midlife may hasten cognitive decline in later life. Researchers from Harvard’s Nurses’ Health Study evaluated cognitive function of almost 1,500 women with type 2 diabetes. Increased intake of saturated and trans fats during midlife was associated with worse cognitive function. The study also showed that a higher polyunsaturated fat to saturated fat ratio was beneficial for cognitive function. Polyunsaturated fat is generally found in plant-based foods, while saturated fat is found mainly in meat and dairy products.
Devore EE, Stampfer MJ, Breteler MMB, et al. Dietary fat intake and cognitive decline in women with type 2 diabetes. Diabetes Care. 2009;32:635-640.