My name is Carrie Johnson and I am a fourth-year PhD candidate at the Sander’s Brown Center on Aging in Dr. Paul Murphy’s lab, and a second-year recipient of the TRIAD T32 fellowship. Our research focuses mainly on Alzheimer’s Disease (AD) and the molecular pathways that are affected by AD pathology. My project within the lab primarily focuses on sex differences in AD related to disrupted sleep patterns. I am very passionate about the work I do here not only because I love sleeping, but also due to the immense impact AD has had on my own life. My best friend’s mother passed away from early onset AD while we were in our 20’s, my grandfather had AD, and my roommate’s grandmother has recently been diagnosed with AD. It is very important to me to be able to understand and explain the complexities of what AD is, how it works, how it affects everyone, and the current status of AD research to those around me.

In the United States, two-thirds of those living with AD are women. Women are on average diagnosed later, experience faster disease progression, and have a higher lifetime risk of developing AD compared to men. Women also have a higher lifetime cost of living with AD and account for more than 60% of caregivers for those living with dementia. It has recently come to light that women may be uniquely vulnerable to both AD and sleep disruption throughout the menopausal transition due to drastic hormonal changes. Universal symptoms experienced during menopause are repeatedly and consistently being linked to poor outcomes in women’s brain health.

Increases in sleep problems are common with advancing age in both men and women, however, these issues increase exponentially in women throughout menopause. When sleep is disrupted, it negatively impacts cognition and overall brain/body health. Disrupted sleep patterns are a strong AD risk factor but how they are linked remains unknown. Research suggests a bi-directional relationship between the two, with sleep problems exacerbating AD risk and disease progression, and AD progression exacerbating sleep problems. It is thought that the link between increased sleep disruption and increased AD risk in women is due to the loss of ovarian hormones (estrogen and progesterone) throughout menopause, and recent studies suggest a more direct link with coinciding increases in certain gonadotropins (follicle stimulating hormone) throughout menopause and beyond. 

My research in AD mouse models has shown that not only do our female mice sleep less and have more AD-related neuropathology than the males, but also that female AD mice are more susceptible to sleep disruptions. These results have replicated across multiple AD mouse lines, indicating a sex-dependent interaction between sleep disruption and AD. Currently I have multiple ongoing experiments examining underlying potential genetic and molecular mechanisms of these sex differences, and have a lot of exciting data to share in the coming months. Additionally, my first paper where I am the first author is currently under review to be published. My primary goal in obtaining my PhD is to bridge the gap when it comes to disparities in healthcare between sex, gender, and AD. I plan to continue AD research, to mentor young women in STEM, to facilitate scientific information to the public in a relatable and engaging manner, and to advocate for science policy at a local level as my career progresses.

Outside of research I also own and operate a small local business called Nerd Babes Co. where I upcycle and repurpose bottles, cans, jars, wood, etc. into functional household items such as soy candles, planters, lamps, table runners, tiki-torches etc. In doing this for 7+ years I have helped the Lexington community keep over 100,000 recyclables out of a landfill, have sponsored community clean ups that resulted in the removal of over 800 pounds of trash from our local waterways, and have raised over $6,000 for local and national non-profit organizations. I have also been able to form numerous collaborations with other local businesses (15 and counting!) to create new items, promote other local conservation initiatives, and have some very unique and once in a lifetime experiences with local wildlife!