Researchers at the University of Calgary have identified a biological mechanism responsible for the increased risk of diseases, such as diabetes, after menopause.
The team found that estrogen promotes the renewal and function of certain stem cells that protect women from cardiometabolic diseases, such as type 2 diabetes, that disrupt the cardiovascular system and are closely linked to heart disease. When estrogen levels decline during menopause, the cells lose their ability to generate healthy fat cells, leading to dysfunction in fat tissue and ultimately metabolic disease.
Taylor Scheidl, left, stands beside her supervisor Jennifer Thompson and labmate Jessica Wager at the Tine Haworth Cardiovascular Research Day. Photo Courtesy: Dawn Smith
Led by Dr. Jennifer Thompson, PhD, an associate professor in the Department of Biochemistry and Molecular Biology at the Cumming School of Medicine, an article sharing the study findings was recently selected as article of the month in the journal Diabetes.
"We know that women are protected from developing diseases like type 2 diabetes in obesity until they hit menopause, but we didn't understand why," says Thompson. "In this study, we identified how adipose progenitor cells contribute to sex differences in metabolic disease susceptibility and the increased risk after menopause."
Adds study first author, Dr. Taylor Scheidl, PhD: "When estrogen drops, the stem cells aren't able to differentiate to form new fat cells. This is the inciting event for metabolic dysfunction throughout the body."
Obesity, defined by excessive body fat accumulation, is a major risk factor for chronic conditions including type 2 diabetes and heart disease. However, the vast majority of research on obesity has been conducted in males.
"By failing to study mechanisms in females, we are missing half the picture," says Scheidl.
Thompson says the findings highlight that obesity biology differs significantly in women, a critical step in developing new prevention and treatment strategies for cardiometabolic disease. The lab is now investigating whether hormone replacement therapy can help preserve healthy fat tissue after menopause.
The research used animal models to focus on adipose progenitor cells, specialized stem cells in fat tissue that generate new fat cells and help maintain healthy fat tissue. In women, these cells appear to play a critical protective role.
This study received funding from Diabetes Canada, the Natural Sciences and Engineering Research Council of Canada and the Canadian Institutes of Health Research.
Jennifer Thompson, PhD, is an associate professor in the Dept. of Biochemistry and Molecular Biology at the Cumming School of Medicine (CSM). She is a member of the Libin Cardiovascular Institute and the Alberta Children's Hospital Research Institute. She is the education lead for the Libin Women's Cardiovascular Health Initiative.
Taylor Scheidl was a PhD student in Cardiovascular and Respiratory Science during this research study. She was also a graduate teaching assistant in Bachelor of Health Sciences at the CSM.
