2021 Alzheimer's Association Research Grant (AARG)

Altered Susceptibility to Alzheimer's disease Due to Pregnancy History

What are the contributions of a woman’s reproductive health to later life risk of Alzheimer’s and other brain changes? 

Zheng Sun, Ph.D.
Baylor College of Medicine
Houston, TX - United States

Background

According to the 2021 Alzheimer’s Association Facts and Figures report, more than 6 million Americans aged 65 or older are living with Alzheimer’s and two-thirds of these are women.  The primary drivers of this difference are unknown. 

Studies have shown that a woman’s reproductive health, including the number of pregnancies and number of years with menstrual cycles, may affect later life risk for Alzheimer’s and dementia. This suggests that there may be contributors of the reproductive pathways – including hormones. Previous research in mice engineered to have Alzheimer’s related brain changes have focused on levels of hormones in later life, but it is unclear how pregnancy-related hormone levels during reproductive age may impact susceptibility to Alzheimer’s later in life.
 

Research Plan

Dr. Zheng Sun and team believe that pregnancy-associated hormonal changes may leave a biological affect that impact woman’s later life risk of Alzheimer’s. They will further this research by studying the impact of high levels of estrogen in genetically engineered female Alzheimer’s-like mice. The researchers will evaluate the impact on the animals’ behavior and brain changes. 

In addition, Dr. Sun and his colleagues will study how high levels of estrogen during reproductive age impacts the activity (turning on and off) of specific genes in the brain later in life, again in genetically engineered Alzheimer’s-like mice and cognitively unimpaired mice.
 

Impact

If successful, the findings may contribute to the knowledge of why there are more women living with Alzheimer’s than men today and a better understanding of what may contribute to later life risk in women and men, helping to address these important scientific questions.