SRF-SRB Exchange Lecture: Fish on Prozac – impacts of pharmaceutical pollution on pre- and post-copulatory sexual selection in aquatic wildlife – Dr Michael Bertram, Swedish University of Agricultural Sciences, Sweden

This talk will cover:

• Pharmaceutical pollution is a rapidly emerging environmental issue, with drugs detected in ecosystems and organisms around the globe.
• Exposure to pharmaceutical contaminants can disrupt reproductive processes in wildlife, with potential flow-on effects on human health.
• Even subtle effects of pharmaceutical exposure on reproduction in wildlife can have significant ecological and evolutionary impacts.
• Viable approaches exist to reduce pharmaceutical pollution but their implementation requires public awareness and political will.

Dr Michael Bertram is a behavioural ecologist / ecotoxicologist based at the Swedish University of Agricultural Sciences in Umeå, Sweden. His research focuses on impacts of human-induced environmental change on ecological and evolutionary processes in wildlife. In particular, he is interested in uncovering how exposure to ‘emerging’ forms of chemical pollution can disrupt complex traits and behavioural processes in wild animals. He addresses these questions using a combination of lab and field approaches in order to uncover how contaminants affect animals across multiple levels of biological organisation, from individuals to populations and communities.

Reproduction Journal Prize Lecture: Alpha-ketoglutarate affects murine embryo development through metabolic and epigenetic modulations – Dr Zhenzhen Zhang, China Agricultural University, China 

α-ketoglutarate (α-KG) is an intermediary metabolite of the tricarboxylic acid (TCA) cycle, which functions to inhibit ATPase and maintain the pluripotency of embryonic stem cells (ESCs); however, little is known regarding the effects of α-KG on the development of preimplantation embryos. Herein, we report that α-KG (150 μM) treatment significantly promoted the blastocyst rate, the number of inner cell mass (ICM) of cells and fetal growth after embryo transfer. The mechanistic studies have revealed two important pathways regarding the α-KG actions on the embryo development. First, it modulates the mitochondria function by controlling the relatively low ATP production without modification of the mitochondrial copy numbers. The relatively low energy metabolism preserves the pluripotency and competence of the ICM. Second, α-KG modifies the epigenetics of the in vitro cultured embryo via affecting the activity of the DNA demethylation enzyme, TET, and the DNA methylation gene, Dnmt3a, to increase the ratio of 5hmC/5mC. The elevated ratio of 5hmC/5mC not only promotes the pluripotency of the ICM but also makes the methylation level of in vitro embryo close to that of an in vivo embryo. All these characteristics of α-KG collectively contribute to the increased number of ICM cells, lead to greater adaptation of the cultured embryo to the in vitro conditions and promote fetal growth after embryo transfer. Our findings provide basic knowledge regarding the mechanisms by which α-KG affects embryo development and cell differentiation.

During Dr Zhenzhen Zhang’s graduate study, she mainly studied the effects and molecular pathways of two natural metabolites, melatonin (MT) and α-ketoglutarate (α-KG) on female animal oocyte maturation, embryonic development and reproductive aging. She thinks many metabolites have the potential to regulate intracellular signal transduction and physiological functions in animal reproduction, which need to be explored in future.