Detection of lindane and 7,12-dimethylbenz[a]anthracene toxicity at low concentrations in a three-dimensional ovarian follicle culture system

Exposure to environmental toxicants that target ovarian follicles can have long-lasting effects on women's reproductive health and health of the offspring. Experiments in rodents have contributed knowledge about the effects of individual toxicants on ovarian follicles. However, little is known about the effects of mixtures of toxicants on ovarian follicular health. We studied the combined effects of low, physiologically- and environmentally-relevant concentrations of toxicants on murine secondary ovarian follicles cultured in an encapsulated three-dimensional (3D) system. Exposure to lindane and 7,12-dimenthylbenz(a)anthracene (DMBA) led to decreased follicle survival, impaired development and compromised maturation in a concentration-dependent manner. DMBA showed a greater toxicity to cultured follicles compared to lindane. The mixtures of lindane and DMBA did not produce a synergistic toxic effect on follicles. Rather, ovarian follicles exposed to the mixtures showed survival and growth patterns similar to the follicles exposed to the same concentrations of individual toxicants. Our findings regarding follicle toxicity at such low concentrations help informing what might be overlooked when regulating environmental toxicants. The proposed 3D culture system allowed studying the effects of mixtures of environmental toxicants in a physiological setting, providing much needed information on how simultaneous exposure to multiple toxicants affects complex and sensitive biological structures, such as ovarian follicles.