E-Poster Presentation ESA-SRB-ANZBMS 2021

Oestrogenic metabolite equol reduces reproductive capacity in drosophila melanogaster over two generations (#612)

Kelsey R Pool 1 , Raveena Gajanayakage 1 , Callum Connolly 1 , Shane Maloney 1 , Dominique Blache 1
  1. University of Western Australia, Crawley, WA, Australia

The role of phytoestrogens as endocrine disrupting agents is of emerging relevance in reproduction, as transgenerational impacts continue to be uncovered. To investigate whether oestrogen-like compound equol could impact reproduction over subsequent generations, a drosophila melanogaster model was used. Male and female flies (P1) were exposed from hatch to a period of peak fertility, to a physiologically relevant level of dietary equol (5mm). P1 were then either mated to a non-exposed partner of the same age, or an exposed partner. The subsequent offspring (F1) were then mated to either a partner from exposed or non-exposed parents. All matings were done in replicates of 10. The seminal vesicles of 5 males per group, per generation were also measured. In the P1 generation, exposure to equol reduced egg-producing capacity from both males and females regardless of whether they were mated to a control or exposed partner (control 31.25 ± 2.9 eggs per lay vs exposed female 20.27 ± 2.7 vs exposed male 15.08 ± 2.3, P=0.006). The number of subsequent offspring (F1) was also reduced (control 16 ±3.1 offspring per mating vs exposed P1 female 5.6 ± 0.3 vs exposed P1 male 2.5 ±  0.5, P<0.001). F1 flies with either a male or female equol-exposed parent had reduced egg-producing capacity (control 48.5 offspring per lay, vs 2.6 exposed female P1, 13.33 exposed male P1,  P =0.015). Male F1 had reduced seminal vesicle size if either parent had been exposed to equol (control 0.0771 ± 0.002 mm2, vs  0.057 ± 0.001 mm2 from exposed female parent, 0.066 ± 0.001 mm2 from exposed male parent,  P =0.015). Male F2 had reduced seminal vesicle size if exposure occured on the maternal side (P= 0.006).  Further work is warranted to determine how equol is able to program the reproductive capacity of exposed individuals and their descendants.