Dr Susan Jobling and Dr Edwin Routledge, Brunel University, and Dr Catherine Jones and Dr Leslie Noble, University of Aberdeen
Of molluscs and men: the snail assay as an alternative to the Hershberger male rodent assay for the detection of androgens and anti-androgens
Abstract of research
Prostate cancer is the third most common cancer in older men, and reproductive disorders and cancers are increasing in younger men and boys. Research has shown that exposure to endocrine disrupting pollutants in the environment may be partly responsible for these trends. This has led to changes in international OECD legislation concerning the safety testing of chemicals which could result in the increased use of animal tests.
The Hershberger test in rats is the current gold standard pre-clinical test used in the development of drugs to treat hormone-dependent male cancers and is currently being considered by European and US regulators as a screen for suspected endocrine disrupting chemicals. A typical test uses 30-50 rats and runs for 10-21 days and more than 210,000 animals are used in reproductive toxicity testing in the UK and Europe each year. However, molluscs are a potential surrogate for mammalian reproductive tests because the reproductive organs and accessory sex glands of snails are functional analogues of the mammalian male reproductive organs and respond to androgenic and anti-androgenic chemicals in a similar way.
The aim of this project is develop a reproductive toxicity test based on the snail response to androgens and anti-androgens that could be used as a replacement for the Hershberger assay. To achieve this, the response of the reproductive tract of the tropical freshwater snail (Biomphalaria glabrata) exposed to androgenic chemicals will be compared to known effects of the same chemicals reported in tests using vertebrates. Initially, in vivo models will be used, but the utility of organ cultures of the mollusc reproductive tract as an in vitro model will also be investigated.
