title: Estrogen replacement improves skeletal muscle performance by increasing parvalbumin levels in ovariectomized rats.
abstract: Muscle weakness is common during menopause. Effective estrogen replacement was hypothesized to prevent sarcopenia. This study aimed to investigate the estrogen level, estrogen receptors (α and β) immunoreactivities, muscle mass and functions, and parvalbumin (PV) levels in the extensor digitorum longus (EDL) and the gastrocnemius muscles of ovariectomized rats. Adult female Wistar rats (12 weeks old) were divided into five groups: sham-operated (SHAM), and ovariectomized (E0) groups that received 10 weeks of estrogen replacements of 0μg/kg (E0), 10μg/kg (E10), 20μg/kg (E20) and 40μg/kg (E40). The estrogen levels, ER α and ER β immunoreactivities, muscle fiber sizes and contractivities and the PV levels were reduced in the E0 group, but increased in all the estrogen replacement groups in both muscles. This study indicated that the reduction of estrogen levels led to a decrease of both ER α and ER β resulting in a decline in muscle mass and PV levels. The decrease of PV levels affected muscle performance, whereas estrogen replacement increased both the ER α and ER β. The increase in the PV levels may result in an improvement of muscle performance. This may explain one mechanism of estrogen on muscle mass and strength in estrogen dependent sarcopenia.
authors.affiliation: Department of Anatomy, Faculty of Science, Prince of Songkla University, Thailand.
authors.forename: Suchirat
authors.initials: S
authors.lastname: Bunratsami
authors.affiliation: Department of Pharmacology, Faculty of Science, Prince of Songkla University, Thailand.
authors.forename: Wandee
authors.initials: W
authors.lastname: Udomuksorn
authors.affiliation: Department of Physiology, Faculty of Science, Prince of Songkla University, Thailand.
authors.forename: Ekkasit
authors.initials: E
authors.lastname: Kumarnsit
authors.affiliation: Department of Oral Surgery (Anesthesiology Section), Faculty of Dentistry, Prince of Songkla University, Thailand.
authors.forename: Surapong
authors.initials: S
authors.lastname: Vongvatcharanon
authors.affiliation: Department of Anatomy, Faculty of Science, Prince of Songkla University, Thailand. Electronic address: uraporn.v@psu.ac.th.
authors.forename: Uraporn
authors.initials: U
authors.lastname: Vongvatcharanon
mesh_terms: D000818:Animals; D047628:Estrogen Receptor alpha / Q000378:metabolism; D047629:Estrogen Receptor beta / Q000378:metabolism; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D020249:Hormone Replacement Therapy; D008593:Menopause; D053580:Muscle Strength / Q000187:drug effects*; D018482:Muscle, Skeletal / Q000503:physiopathology*; D010052:Ovariectomy; D010320:Parvalbumins / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D004967:Estrogens; D010320:Parvalbumins
keywords: Estrogen; Estrogen receptor; Ovariectomy; Parvalbumin; Rat; Sarcopenia; Skeletal muscle performance