Estrogen-Receptors, Estrogen, Exercise, Mice-Exercise-Physiological effect, Mice-Muscles, Musculoskeletal system, Murine, Skeletal muscle
Repairable skeletal muscle damage is an occurrence that everyone experiences. The most common route of damage is through exercise, and more specifically eccentric exercise. During eccentric contractions the muscle lengthens generating tension that leads to molecular damage. After exercise, reactive oxygen species ((ROS) are elevated in skeletal muscle in response to an increase in oxidative phosphorylation and an infiltration of macrophages to damaged tissue (Urso and Clarkson, 2003). The hormone estrogen carries antioxidant properties, which allows for the possibility of protection from peroxidative damage and may have an influence on post-injury inflammatory response (Tildus, 2001). Estrogen exerts its effects on tissue by binding to one of its receptors. There are three proteins that are classified as estrogen receptors (ERs): ERл±, ERл_ and G-protein coupled estrogen receptor (GPER). This study investigated how the three estrogen receptors change in exercise naive mice after an eccentrically biased bout of exercise. It also investigated gender dimorphism of estrogen receptors. Mice were run downhill at a -15еЎ decline for a total of 15 min. Murine biceps were removed under protocols approved by the Smith College IACUC. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) followed by immunoblot analysis was used to investigate expression of the proteins at different time points after exercise. In the study, gender dimorphism is apparent for the ERл± controls, however was not observed for GPER or ERл_ controls. Protein expression decreases after exercise as a function of time moderated by sex for ERл± and GPER for both genders. Finally, ERл_ is not prominent in murine skeletal muscle.
Gelzinis, Justine Amber, "Estrogen receptor analysis after a single bout of exercise in murine biceps brachii" (2014). Masters Thesis, Smith College, Northampton, MA.