Bisphenol A (BPA) replacements cause reproductive problems in lab mice
Twenty years ago, US researchers made the accidental discovery that the now infamous plastics ingredient known as bisphenol A (BPA) had leached out of plastic cages used to house female mice in the lab, causing a sudden increase in chromosomally abnormal eggs in the animals. Now, the same team reports in Current Biology that the array of alternative bisphenols currently used to replace BPA in BPA-free bottles, cups, cages and other items appear to come with similar problems for their mice. The same researchers again noticed a change in the data coming out of studies on control animals. Again, they traced the problem to contamination from damaged cages, but the effects this time were more subtle than before. Not all of the cages were damaged and the source of contamination remained less certain. The researchers were able to determine that the mice were being exposed to replacement bisphenols. They also saw that the disturbance in the lab was causing problems in the production of both eggs and sperm. Once they got the contamination under control, the researchers conducted additional controlled studies to test the effects of several replacement bisphenols, including a common replacement known as BPS. Those studies confirm that replacement bisphenols produce remarkably similar chromosomal abnormalities to those seen so many years earlier in studies of BPA. These problems, if they hold true in people as has been shown in the case of BPA, will carry over to future generations through their effects on the germline. The researchers showed that if it were possible to eliminate bisphenol contaminants completely, the effects in mice would still persist for about three generations. More work is needed to determine whether some replacement bisphenols might be safer than others. Other widely used and endocrine-disrupting chemicals, including parabens, phthalates and flame retardants, may be having similar adverse effects on fertility that warrant further study.
Animal research: is it time to open up the laboratories?
Australian scientists, universities and research institutions have been urged to be more open with the public about how laboratory animals are used and why they are needed in scientific research. A more informed ethical debate should also take into account the strict regulatory protection for animals in laboratories. Speaking at the Australian and New Zealand Laboratory Animal Science Association conference in Melbourne, Bella Williams from the British organisation Understanding Animal Research said that recent years have seen a complete turnaround in how UK research institutions engage with the public over their use of animals in scientific studies, and that Australia was lagging behind. “In the past, intimidation by a small extremist element pushed many in the research community to become almost secretive about their use of animals. Unfortunately, the public was left to assume the worst despite the UK research being strictly regulated with high animal welfare standards. This has now changed dramatically. Since 2012, over 120 of Britain’s top universities, research institutions and pharmaceutical companies have signed a public pledge committing them to greater openness in their animal research programs. As well as posting details of their animal research on their public websites, some have even provided virtual tours of their animal facilities.” The pledge, known as the Concordat on Openness on Animal Research in the UK, requires institutions to commit to providing clear, publicly available information about their use of animals through proactive communication strategies and regular reviews of progress. Increasingly, organisations around the world are taking similar steps towards greater transparency, reflecting public expectations that organisations are clear about their approach to ethical issues. Spokesperson for the Australian and New Zealand Laboratory Animal Association, Malcolm France, says the research community in Australia is often reluctant to engage openly about animal research. “Unfortunately, this does nothing to support informed discussion. Many people still think that cosmetics are tested on animals in Australia even though this has never actually happened here. Australian regulations for protecting animals in research are ranked among the highest internationally and animal research has played a role in some of Australia’s most important medical breakthroughs: cochlear implants, cervical cancer vaccine and [anti-influenza] medication all have a basis in animal research. Animal research will always be an ethically complex area. But with greater openness, at least the debate can become better informed.”
New tool to detect fatty liver disease before liver damage
An international research team led by the Westmead Institute for Medical Research has developed a new test, which may soon be available, to predict advanced fibrosis in people with non-alcoholic fatty liver disease (NAFLD). NAFLD is the leading cause of chronic liver disease, affecting approximately one in four people, including children, worldwide. The team developed a score, based on the PRO-C3 biological marker, to accurately predict the presence (or absence) of advanced fibrosis in people with NAFLD. They found that PRO-C3 progressively increases as fibrosis becomes more severe. The team combined these data with routine clinical information – such as age, presence of diabetes, and platelet count – to develop a highly accurate tool to detect advanced fibrosis in NAFLD. The results exceed existing fibrosis scores, accurately identifying 92% of patients with advanced fibrosis. NAFLD – also known as “fatty liver” – occurs when more than 5% of the liver is made up of fatty tissue. As the name suggests, it affects people who drink little to no alcohol. Physical inactivity and obesity were some of the leading causes behind the global rise in NAFLD. Non-alcoholic fatty liver disease also increases the risk of developing type 2 diabetes and cardiovascular diseases. The study investigated 431 patients from across Australia, the UK and Japan, and is published in Hepatology.
What’s new online at the MJA
17 September Podcast with Professor Jeremy Chapman, Director of Renal Medicine at Westmead Hospital in Sydney … OPEN ACCESS permanently
17 September Podcast with Professor Louise Baur, AM, Head of Child and Adolescent Health at Sydney Medical School and Head of the Children’s Hospital Westmead Clinical School … OPEN ACCESS permanently
To find a doctor, or a job, to use GP Desktop and Doctors Health, book and track your CPD, and buy textbooks and guidelines, visit doctorportal.