Cardiovascular disease Mutations in ERβ have been shown to influence
cardiomyocytes, the cells that comprise the largest part of the heart, and can lead to an increased risk of
cardiovascular disease (CVD). There is a disparity in prevalence of CVD between pre- and post-menopausal women, and the difference can be attributed to estrogen levels. Many types of ERβ receptors exist in order to help regulate gene expression and subsequent health in the body, but binding of 17βE2 (a naturally occurring estrogen) specifically improves cardiac metabolism. The heart utilizes a lot of energy in the form of
ATP to properly pump blood and maintain physiological requirements in order to live, and 17βE2 helps by increasing these myocardial ATP levels and respiratory function. In addition, 17βE2 can alter myocardial signaling pathways and stimulate myocyte regeneration, which can aid in inhibiting myocyte cell death. The ERβ signaling pathway plays a role in both
vasodilation and
arterial dilation, which contributes to an individual having a healthy heart rate and a decrease in blood pressure. This regulation can increase
endothelial function and
arterial perfusion, both of which are important to myocyte health. Thus, alterations in this signaling pathways due to ERβ mutation could lead to myocyte cell death from physiological stress. While ERα has a more profound role in regeneration after myocyte cell death, ERβ can still help by increasing
endothelial progenitor cell activation and subsequent cardiac function.
Alzheimer's disease Genetic variation in ERβ is both sex and age dependent and ERβ polymorphism can lead to accelerated brain aging, cognitive impairment, and development of AD pathology. Similar to CVD, post-menopausal women have an increased risk of developing
Alzheimer's disease (AD) due to a loss of estrogen, which affects proper aging of the
hippocampus, neural survival and
regeneration, and
amyloid metabolism. ERβ mRNA is highly expressed in hippocampal formation, an area of the brain that is associated with memory. This expression contributes to increased neuronal survival and helps protect against neurodegenerative diseases such as AD. The pathology of AD is also associated with accumulation of
amyloid beta peptide (Aβ). While a proper concentration of Aβ in the brain is important for healthy functioning, too much can lead to cognitive impairment. Thus, ERβ helps control Aβ levels by maintaining the protein it is derived from, β-amyloid precursor protein. ERβ helps by up-regulating
insulin-degrading enzyme (IDE), which leads to β-amyloid degradation when accumulation levels begin to rise. However, in AD, lack of ERβ causes a decrease in this degradation and an increase in plaque build-up. ERβ also plays a role in regulating
APOE, a risk factor for AD that redistributes lipids across cells. APOE expression in the hippocampus is specifically regulated by 17βE2, affecting learning and memory in individuals afflicted with AD. Thus, estrogen therapy via an ERβ-targeted approach can be used as a prevention method for AD either before or at the onset of menopause. Interactions between ERα and ERβ can lead to antagonistic actions in the brain, so an ERβ-targeted approach can increase therapeutic neural responses independently of ERα. Therapeutically, ERβ can be used in both men and women in order to regulate plaque formation in the brain. ==Neuroprotective benefits==