Low levels of gonadal circulating estrogen observed in post-menopausal women can adversely impact a diverse range of physiological factors, with clinical implications for brain cognition, gut health, the female reproductive tract and other aspects of women's health. One of the principal regulators of circulating estrogens is the gut microbiome. This review aims to shed light on the role of the gut microbiota in estrogen-modulated disease. The gut microbiota regulates estrogens through secretion of β-glucuronidase, an enzyme that deconjugates estrogens into their active forms. When this process is impaired through dysbiosis of gut microbiota, characterized by lower microbial diversity, the decrease in deconjugation results in a reduction of circulating estrogens. The alteration in circulating estrogens may contribute to the development of conditions discussed herein: obesity, metabolic syndrome, cancer, endometrial hyperplasia, endometriosis, polycystic ovary syndrome, fertility, cardiovascular disease (CVD) and cognitive function. The bi-directional relationship between the metabolic profile (including estrogen levels) and gut microbiota in estrogen-driven disease will also be discussed. Promising therapeutic interventions manipulating the gut microbiome and the metabolic profile of estrogen-driven disease, such as bariatric surgery and metformin, will be detailed. Modulation of the microbiome composition subsequently impacts the metabolic profile, and vice versa, and has been shown to alleviate many of the estrogen-modulated disease states. Last, we highlight promising research interventions in the field, such as dietary therapeutics, and discuss areas that provide exciting unexplored topics of study.

While high-risk human papillomavirus (HPV) infection is a well-established risk factor for cervical cancer, there are likely other factors within the local microenvironment that contribute to cervical carcinogenesis. Here we investigated relationships between HPV, vaginal pH, vaginal microbiota (VMB) composition, level of genital immune mediators and severity of cervical neoplasm. We enrolled women with low- and high-grade cervical dysplasia (LGD, HGD), invasive cervical carcinoma (ICC), and healthy controls. HPV16, HPV45, HPV58, and HPV31 were the most prevalent in our cohort with HPV16 and HPV31 genotypes more prevalent in Hispanics. Vaginal pH was associated with ethnicity and severity of cervical neoplasm. Lactobacillus dominance decreased with the severity of cervical neoplasm, which correlated with elevated vaginal pH. Hispanic ethnicity was also associated with decreased Lactobacillus dominance. Furthermore, Sneathia was enriched in all precancerous groups, ICC, abnormal pH and Hispanic origin. Patients with ICC, but not LGD and HGD, exhibited increased genital inflammatory scores and elevated specific immune mediators. Notably, IL-36γ was significantly associated with ICC. Our study revealed local, host immune and microbial signatures associated with cervical carcinogenesis and provides an initial step to understanding the complex interplay between mucosal inflammation, HPV persistence and the VMB.

Appropriately simulating the three-dimensional (3D) environment in which tissues normally develop and function is crucial for engineering in vitro models that can be used for the meaningful dissection of host-pathogen interactions. This Review highlights how the rotating wall vessel bioreactor has been used to establish 3D hierarchical models that range in complexity from a single cell type to multicellular co-culture models that recapitulate the 3D architecture of tissues observed in vivo. The application of these models to the study of infectious diseases is discussed.