Joshua Johnson, Ph.D.

Joshua Johnson, Ph.D. is Associate Professor at Anschutz Medical Campus at the University of Colorado. He is the Principle Investigator at the Johnson Lab, working on basic and translational studies of the mammalian ovary.

His laboratory is part of the Division of Reproductive Sciences and the Division of Reproductive Endocrinology within the Department of Obstetrics and Gynecology at the University of Colorado Anschutz Medical Campus in Aurora, Colorado.

His overall goal is to improve the health and well-being of women. In one central project, he is investigating the mechanisms that lead to accelerated female reproductive aging, which can manifest when ovarian function ceases early in life relative to the expected time of menopause.

Joshua’s research program focuses on controlling oocyte number inside the ovary, primarily in mammals, but also in the fruit fly model organism. He currently focuses on mechanisms that support oocyte quality, the ability to give rise to a healthy offspring, and those that lead to oocyte loss, due to ‘normal’ aging and in the context of human premature ovarian failure (POF).

What actually causes menopause? We know generally that when the ovarian reserve of primordial follicles (that contain eggs) declines to a certain point, menopause will soon follow. We also know that the onset of the menopausal transition, when menstrual cycles become irregular, indicates that menopause will follow…but when? Read What actually causes menopause? Read Mathematical recapitulation of the end stages of human ovarian aging.

His group is focused on mechanisms that control primordial follicle growth activation (PFGA). The reason for this focus is that the rate of loss of the primordial reserve of follicles determines whether a woman will experience a ‘normal’ duration of ovarian function, or instead, face primary ovarian insufficiency (POI) where ovarian function ceases before the age of 40.

Approximately 1 in 250 women will experience POI before age 35, and 1 in 100 before age 40. An additional 5% of women experience ovarian failure between 40 and 45 years, outside the definition of POI. In combination, the cost of POI to individuals and society is extraordinarily high.

If afflicted with POI, women can face decades of increased risk for these problems of aging and their treatment limitations. Further characterizing the mechanism(s) that drive PFGA, and thus ovarian aging, will fill major gaps in our understanding of this critical biological process. This may lead to future interventions to slow ovarian aging and improve the health of women.

To maximize his clinical/translation acumen, Joshua was trained and worked part-time as an embryologist at the Yale IVF Center between 2005 and 2016. His primary mission is to understand the function of the ovary better so they can first identify women whose ovaries are at risk of failing or who will have trouble conceiving, and one day intervene to protect fertility and organ function.

Joshua earned his Ph.D. in Biology from Arizona State University in 2002. His thesis work was titled Notch signaling during mouse ovarian follicle development.

He earned his Bachelor’s Degree of Science in Biology in 1995 from the University of Wisconsin-Madison. Joshua was Postdoctoral Fellow at the Massachusetts General Hospital between 2002 and 2005, working in the Vincent Center for Reproductive Biology.

Read Recapitulating human ovarian aging using random walks, Why is there an “oversupply” of human ovarian follicles?, Slowest first passage times, redundancy, and menopause timing, and Integrated stress response control of granulosa cell translation and proliferation during normal ovarian follicle development.

Read Germline stem cells and follicular renewal in the postnatal mammalian ovary.

Visit his LinkedIn profile and Google Scholar page. Follow him on ORCiD, GitHub, and Twitter.