PhD student
Research Institute for Environmental and Occupational Health (IRSET) INSERM UMR 1085

Who is Pauline LELANDAIS?

I am a French PhD student currently based In Rennes, France, and carrying out my PhD research under the supervision of Dr Séverine Mazaud-Guittot at the Research Institute for Environmental and Occupational Health (IRSET). The question of the effects of environmental substances of the health and the linked rising health Issues Is something that always touched me. That’s why, after a Bachelor degree In life sciences that I did In Normandy, where I’m from, and a Master degree In Cell biology and Reproduction and Development In Paris, I joined the IRSET In 2019 to start my PhD In the toxicology field and work on the FREIA project. 

Out of the lab, I love doing a lot of sport, reading, and have developed, since my childhood, a passion for fashion.

What is your focus/role in the FREIA project?

Fetal life is a key window for the establishment of female reproductive function, especially through the development of the ovary. In the framework of the workpackage 1, I work with a model of organotypic culture of human fetal ovary to screen the mechanistic effects of different concentrations of two models of endocrine disruptors, the Diethyltilbestrol and the Ketoconazole, in this organ during critical windows of fetal life. This work is carried out with the aim of screening an exhaustive range of endpoints to establish the best test strategies for the Identification of toxic substances for female reproduction in a regulatory context.

What is an interesting result you have obtained so far? 

The Ketoconazole (KTZ), known to be a strong inhibitor of steroidogenesis, disrupts estrogen production by human fetal ovaries, even at sub-toxic concentrations. The production of another ovarian hormone, Inhibin B, Is also disrupted by this endocrine disruptor, but in a non-linear fashion. Finally, I showed a similar decrease in total ovarian and germ cell populations which suggests that germ cells may not display a specific sensitivity to KTZ. Future transcriptomic study that will be obtained by BRBseq should bring us mechanistic information about the mechanisms of KTZ toxicity and we also expect to get further insights into the mechanisms of endocrine disruption in human fetal ovary.

What would you like to accomplish within the FREIA project?

I have always been sensitive to the question of the harmful effects of environmental substances on health, and joining this project allows me to make my contribution in the efforts implemented against this growing public health issue. I know that solutions and changes will take time to reach a safer world In terms of environmental pollutants. However, I am proud to be a part of the FREIA team to better understand mechanisms linked to endocrine disruption In female reproduction and set up the necessary strategies to Improve the female health In the next years. 

How is the COVID-19 pandemic affecting you/your work?

The COVID-19 pandemic severely reduced the number of samples we get from the Rennes Sud hospital which undeniably impacted my work since my research are directly related to culture of human fetal organs. Although sample collection Is gradually getting back to normal, we are still facing a delay regarding the reminding samples we need for the transcriptomic study. However, we are constantly finding solutions to Overcome this Issue linked to the pandemic, and to be able to achieve our goals.

Is there anything else you would like to share with the people following FREIA?

I think that now, a large majority of people has heard of endocrine disruptors and are aware of their deleterious effects on health. Setting up a safer world by limiting our contact with harmful substances is what we would like to reach with the FREIA project, and raise awareness of the effects of endocrine disruptors is also a way to get there. Making better decisions about this in the future will not only be possible thanks to research, but also thanks to each of us!