Reproductive evaluations in female rat offspring exposed to metformin during intrauterine and intrauterine/lactational periods.

Metformin (MET) is a widely-used drug for the treatment of type 2 diabetes mellitus and gestational diabetes. It is known that metformin crosses the placenta and can to be transferred through milk. In vitro studies show that MET decreases gonadotropin-releasing hormone and gonadotropins release in rat neurons, and decreases progesterone and estradiol in rat granulosa cells and androstenedione synthesis in human theca cells. This study evaluated whether MET maternal exposure might interfere with reproductive parameters of female offspring. Wistar female rats were treated with MET 293 mg/kg/day, by gavage, from gestational day (GD) 0 to GD 21 (METG) or GD 0 until lactation day (LD) 21 (METGL). Controls groups received water. An increase in plasmatic estradiol levels was observed during the estrus stage in the METGL group. This result suggests that exposure to MET during gestational and lactational periods might be related to programming in theca and/or granulosa cells during development.

Evaluation of reproductive toxicity in rats treated with triclosan.

Triclosan (TCS) is an antibacterial agent used in a variety of consumer products such as: soaps, deodorant, and toothpaste, among others. Some studies have reported the (anti)androgenic effects of TCS in the male reproductive system, raising concerns about its effects on the reproductive axis. In this study, the (anti)androgenicity of TCS was evaluated in the Hershberger assay in 52-day old male Wistar rats. Additionally, the sexual behavior, sperm motility, sperm viability, and testicular histomorphometry were evaluated in a second protocol to investigate the reproductive effects of TCS in 49-day old male Wistar rats. The dosages were administered based on the acceptable daily intake for TCS, in addition to 3 and 10-fold higher doses. Our results demonstrated that TCS, in the doses administered, did not act as an endocrine disrupter (ED), with no (anti)androgenic effect in the Hershberger assay and without interfering with the parameters evaluated in the reproductive toxicity study.