Sanderson Thomas

Biography

J. Thomas Sanderson completed a Bachelor's degree (B.Sc., 1989) in Chemistry from Vrije Universiteit in Amsterdam, the Netherlands, and a Ph.D. (Ph.D., 1994) in pharmacology and toxicology from the University from British Columbia to Vancouver, Canada. After a postdoctoral fellowship at the Michigan State University (1994-1997), he was appointed Assistant Professor at the University of Utrecht, Netherlands (Institute for Risk Assessment Sciences, 1997-2005). ), where he received his tenure in 2003. Since 2005, Thomas Sanderson holds an associate professor position at the INRS-Institut Armand-Frappier, focusing on the interaction between chemicals and biosynthesis enzymes. steroids, linked to the development of hormone-dependent cancers and endocrine disruptions.

Research Interest

Some pesticides, environmental contaminants, drugs (human and veterinary) and naturally occurring products can interfere with steroid biosynthesis and metabolism in humans and wildlife. The mechanisms of deregulation of steroidogenesis by chemicals and toxicological consequences are unexplored fields of research but are currently of great interest given concern about endocrine disruptors, increased frequency of hormone- dependence and a greater incidence of reproductive problems in humans and wildlife. My current research focuses on the synthesis and metabolism of estrogens and androgens by the various enzymes of cytochrome P450 and reductases that are present in steroidogenic tissues and hormone-dependent tumors. Particularly, enzymes such as CYP19 (aromatase), CYP17 and 5? -reductase, among others, are of immense interest because their high expression is associated with a greater risk of certain cancers. I focus on how chemicals disrupt the expression or catalytic activity of steroidogenic enzymes in the various cellular systems of mammals and fauna and in vivo in transgenic mice. The induction by xenobiotics is regulated by intracellular messengers such as cAMP and protein kinase A in gonads and adrenocortical cells (Sanderson et al., 2004). However, in other target tissues, other transduction pathways (PKC, Jak / Stat, glucocorticoid) are involved (Heneweer et al., 2004). This work will be extended to the study of primary cultures of human tissue cells and those of wildlife. Various natural (plant-derived) products are known to interfere with steroidogenesis and / or metabolism and to act as agonists or antagonists for estrogen and androgen receptors. However, specific enzymes or target receptors are unknown for several of these products. As part of a long-term project funded by NSERC, the inducing or inhibiting properties of natural polyphenolic products and synthetic analogs will be examined and structure-activity relationships will be described. The in vitro effects of chemicals on steroid synthesis are highly dependent on tissue types and do not take into account biokinetic factors such as absorption, distribution and metabolism. A limited number of in vivo studies will be performed to confirm in vitro results and to validate cell biological assays as useful and predictive models for in vivo effects. The in vitro effects of chemicals on steroid synthesis are highly dependent on tissue types and do not take into account biokinetic factors such as absorption, distribution and metabolism. A limited number of in vivo studies will be performed to confirm in vitro results and to validate cell biological assays as useful and predictive models for in vivo effects. The in vitro effects of chemicals on steroid synthesis are highly dependent on tissue types and do not take into account biokinetic factors such as absorption, distribution and metabolism. A limited number of in vivo studies will be performed to confirm in vitro results and to validate cell biological assays as useful and predictive models for in vivo effects.