Menopause-related mitochondrial dysfunction ups CVD risk in older women
Researchers have identified what they believe is a molecular explanation for why cardiovascular disease (CVD) occurs later in women than in men.
Estrogen may improve the function of cellular mitochondria and limit inflammation, a known contributor to CVD, Maria Luisa Barcena De Arellano, PhD, reported during an April 21 presentation at Frontiers in Cardiovascular Biology 2018 in Vienna. But when estrogen levels fall with menopause, female hearts begin shifting to a more pro-inflammatory state.
Barcena De Arellano said this process may explain why ischemic heart disease tends to develop an average of seven to 10 years later in women than in men.
The researchers looked at heart tissue from seven women and seven men aged 17 to 40 and eight women and nine men aged 50 to 68. All study participants were free of CVD.
Barcena De Arellano and colleagues found levels of specific proteins and antioxidants—Sirt1 and superoxide dismutase 2—were higher in young women than in young men, but that difference diminished with age. Catalase, an enzyme that protects cells against oxidative damage, also followed a similar path.
“We found that the hearts of older women have reduced expression of antioxidant proteins and proteins that are important for mitochondrial function,” Barcena De Arellano said in a press release. “This may lead to the increased inflammation we observed in older women. … We think that the fall in estrogen with menopause contributes to mitochondrial dysfunction.”
Hormone replacement therapy could be used to boost estrogen levels and protect postmenopausal women from CVD, Barcena De Arellano said. But, she acknowledged, hormone replacement may not be suitable for all women, paving the way for novel pharmaceuticals to be explored.
“Our study suggests that a new drug could be developed which increases the expression of mitochondrial proteins,” she said. “This could improve mitochondrial function, reduce inflammation, and help to prevent cardiovascular disease in older women.”
Daniel joined TriMed’s Chicago editorial team in 2017 as a Cardiovascular Business writer. He previously worked as a writer for daily newspapers in North Dakota and Indiana.