Prenatal exposure to Di(2-ethylhexyl) phthalate and high-fat diet synergistically disrupts gonadal function in male mice†.

Prenatal exposure to Di (2-ethylhexyl) phthalate (DEHP) impairs the reproductive system and causes fertility defects in male offspring. Additionally, high-fat (HF) diet is a risk factor for reproductive disorders in males. In this study, we tested the hypothesis that prenatal exposure to a physiologically relevant dose of DEHP in conjunction with HF diet synergistically impacts reproductive function and fertility in male offspring.

Single neonatal estrogen implant sterilizes female animals by decreasing hypothalamic KISS1 expression.

Reproductive sterilization by surgical gonadectomy is strongly advocated to help manage animal populations, especially domesticated pets, and to prevent reproductive behaviors and diseases. This study explored the use of a single-injection method to induce sterility in female animals as an alternative to surgical ovariohysterectomy. The idea was based on our recent finding that repetitive daily injection of estrogen into neonatal rats disrupted hypothalamic expression of Kisspeptin (KISS1), the neuropeptide that triggers and regulates pulsatile secretion of GnRH.

Prenatal exposure to an environmentally relevant phthalate mixture disrupts testicular steroidogenesis in adult male mice.

Endocrine disrupting chemicals (EDCs) in the environment are considered to be a contributing factor to the decline in the sperm quality. With growing evidence of the harmful effects of EDCs on the male reproductive system, we tested the hypothesis that prenatal exposure to an environmentally relevant phthalate mixture adversely affects reproductive outcomes and androgen synthesis. In this study, an environmentally relevant composition of phthalates (15% DiNP, 21% DEHP, 36% DEP, 15% DBP, 8% DiBP, and 5% BBzP) that were detected in urine samples of pregnant women in Illinois, United States, was used.

Generation and characterization of an estrogen receptor alpha-iCre knock-in mouse.

Two estrogen receptors, ESR1 and ESR2, are responsible for the classical actions of estrogens in mammalian species. They display different spatiotemporal expression patterns and nonoverlapping functions in various tissues and physiological conditions. In this study, a novel knock-in mouse line that expresses codon-improved Cre recombinase (iCre) under regulation of the natural Esr1 promoter (Esr1-iCre) was developed.

Granulosa cell endothelin-2 expression is fundamental for ovulatory follicle rupture.

Ovulation is dependent upon numerous factors mediating follicular growth, vascularization, and ultimately oocyte release via follicle rupture. Endothelin-2 (EDN2) is a potent vasoconstrictor that is transiently produced prior to follicle rupture by granulosa cells of periovulatory follicles and induces ovarian contraction. To determine the role of Edn2 expression, surgical transplant and novel conditional knockout mice were super-ovulated and analyzed.

Prenatal Exposure to DEHP Induces Premature Reproductive Senescence in Male Mice.

Di-(2-ethylhexyl) phthalate (DEHP) is the most commonly used phthalate, and it is an endocrine-disrupting chemical. This study tested a hypothesis that prenatal exposure to DEHP lays the foundation for premature gonadal dysfunction and subsequent reproductive senescence in male mice. Pregnant female CD-1 mice were orally dosed with vehicle control (tocopherol-stripped corn oil) or with 20 μg/kg/day, 200 μg/kg/day, 500 mg/kg/day, or 750 mg/kg/day of DEHP from gestational day 11 to birth.