In vitro preclinical modeling of sex-specific biology and hormonal dynamics in women's health: insights across multiple organs

Hormonal fluctuations in women have major impacts on organ physiology, contributing to well-recognized sex differences in disease susceptibility and manifestations, as well as therapeutic responses. Yet, most experimental studies and preclinical models fail to take sex-specific differences in tissue responses or changes in female hormones into consideration. In this Minireview, we highlight the importance of incorporating hormonal dynamics in experimental design and focus on emerging in vitro new approach methodologies (NAMs), including primary human cell cultures, organoids, and microfluidic human organ-on-a-chip (Organ Chip) models, which are being used to study hormone-dependent biology across multiple organ systems in a more clinically relevant way. Clinical data linking estrogen and progesterone signaling to sex-specific disease manifestations and the limitations of association-based studies are first reviewed. Then we describe how new human-relevant NAMs that can replicate female hormone-dependent exposures and responses in vitro may be used to dissect disease mechanisms and discuss each model's unique advantages and disadvantages. We also consider how these new approaches may be used as preclinical models for drug development, toxicity testing, and personalized medicine in the future.