Study: Environmental pollutants affect male reproduction in many species, including humans

In the St. Lawrence River near Montreal's sewage discharge site, male spottail shiners show the effects of pollution with more than one third of the fish having oocytes in their testes. This is one of many examples of Professor Daniel Cyr's research at INRS, during which he has studied the effects of human activity on male fertility in various species, including man. His research has received significant recognition and support, including the recently awarded Canada Research Chair in Reproductive Toxicology.

Environmental pollutants affect male reproduction in many species, including humans. Numerous substances interfere with finely tuned hormonal signaling mechanisms, resulting in multiple pathologies, including infertility. Professor Cyr's research focuses primarily on understanding how environmental pollutants can affect sperm maturation, a process that occurs in the epididymis, where sperm acquires the ability to swim and fertilize.

Prof. Cyr's research team has developed novel tools to study human epididymal function, including unique rodent and human cell lines to understand how genes can be altered in the epididymis, resulting in infertility. Of significance is the role of a cellular barrier in the epididymis, which protects the maturing sperm from the immune system while creating an environment that is necessary for sperm maturation. How environmental contaminants can alter this barrier, threatening sperm development and, consequently, male fertility remains a major focus of research.

Knowledge acquired through the activities of the new chair will contribute to the development of novel methods and data that will provide better guidelines for more effective ecosystem protection, in particular by helping to establish standards and strategies for governments.