Stimulation of mitochondrial embryo metabolism by dichloroacetic acid in an aged mouse model improves embryo development and viability

Objective: To determine whether supplementation of embryo culture media with a substrate to stimulate mitochondrial activity improves embryo viability and pregnancy establishment in aged mice.

Design: Female mice were superovulated and mated. Zygotes were collected and cultured in either G1/G2 or G1/G2 with 1.0 mM dichloroacetic acid (DCA), a stimulator of pyruvate dehydrogenase complex. Embryos were cultured to the blastocyst stage and transferred into pseudopregnant female mice.

Setting: University research facility.

Animal(s): Swiss female mice 26- to 28-week-old.

Intervention(s): The addition of DCA to the embryo culture media.

Main outcome measure(s): Embryo development, total, trophectoderm, inner cell mass (ICM) and epiblast cell number, mitochondrial membrane potential, reactive oxygen species, pyruvate oxidation, adenosine triphosphate (ATP) output, implantation rates, and fetal and placental size and weights.

Result(s): Supplementation of the embryo culture medium with DCA significantly increased blastocyst development rates in vitro, significantly improved total, trophectoderm, and ICM cell numbers and pluripotency of the ICM, significantly increased pyruvate oxidation and ATP output, and significantly increased fetal weights and size comparable to in vivo conditions.

Conclusion(s): This study demonstrates that the addition of DCA to embryo culture media improves mitochondrial output in embryos produced from aged mice. Although DCA itself may be of limited therapeutic value in a clinical setting due to its low threshold of dosage and high toxicity, this proof of concept study does suggest that the addition of a physiological-based mitochondrial stimulator to embryo culture media for aged women may potentially improve IVF outcomes.