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Known as the female hormone, 'Estrogen' is a group of compounds that tends to work in opposition to androgens (like testosterone) and mediate fat metabolism, cognition, blood flow, and female reproduction. Men sometimes wish to lower estrogen via aromatase inhibition.

Our evidence-based analysis on estrogen features 89 unique references to scientific papers.

Research analysis led by and reviewed by the Examine team.
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Research Breakdown on Estrogen

1Skeletal Muscle and Hypertrophy


Both the alpha subset (ERα) and beta subset (ERβ) of the estrogen receptor are present in the skeletal muscle tissue of rats[1][2] and humans[3][4][5] of both sexes.

Estradiol is known to attenuate the rate of inflammatory processes following damaging exercise[6] (also seen in ischemia/reperfusion[7]) by reducing neutrophil accumulation, which is thought to explain the reduce rates of muscle tissue regeneration in ovarectomized rats (model of menopause) relative to those given estrogen[8][9] with similar effects in male rats[10] and is thought to explain the higher than average rates of sarcopenia observed in menopausal women relative to premenopausal women[11] which is alleviated with hormone replacement therapy.[12] This anti-inflammatory response does not appear to be mediated by either estrogen receptor.[13]

Treatment of male[14] and female[15] rats with estradiol results in increased muscle cell recruitment following damaging exercise by an estrogen receptor dependent mean[13] and particularly satellite cell recruitment is mediated through the alpha subset (ERα).[16]

Selective activation of the β subset (ERβ) results in muscle protein synthesis, as ablation of the receptor exacerbates damage from exercise while treatment with agonists causes satellite cell activation and proliferation;[17] Activation of ERβ appears to enhance IGF-1 related anabolic pathways.[17]

Both estrogen receptors and injections of estrogen (to reach a higher circulating level) are associated with increased recovery rates of skeletal muscle secondary to anti-inflammatory effects and increased satellite cell activation


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  2. ^ Milanesi L, et al. Expression and subcellular distribution of native estrogen receptor beta in murine C2C12 cells and skeletal muscle tissue. Steroids. (2009)
  3. ^ Wiik A, et al. Oestrogen receptor beta is expressed in adult human skeletal muscle both at the mRNA and protein level. Acta Physiol Scand. (2003)
  4. ^ Wiik A, et al. Expression of both oestrogen receptor alpha and beta in human skeletal muscle tissue. Histochem Cell Biol. (2009)
  5. ^ Wiik A, et al. Oestrogen receptor beta is present in both muscle fibres and endothelial cells within human skeletal muscle tissue. Histochem Cell Biol. (2005)
  6. ^ Tiidus PM, et al. Estrogen effect on post-exercise skeletal muscle neutrophil infiltration and calpain activity. Can J Physiol Pharmacol. (2001)
  7. ^ Stupka N, Tiidus PM. Effects of ovariectomy and estrogen on ischemia-reperfusion injury in hindlimbs of female rats. J Appl Physiol. (2001)
  8. ^ Sitnick M, et al. Ovariectomy prevents the recovery of atrophied gastrocnemius skeletal muscle mass. J Appl Physiol. (2006)
  9. ^ McClung JM, et al. Estrogen status and skeletal muscle recovery from disuse atrophy. J Appl Physiol. (2006)
  10. ^ Sugiura T, et al. Estrogen administration attenuates immobilization-induced skeletal muscle atrophy in male rats. J Physiol Sci. (2006)
  11. ^ Walsh MC, Hunter GR, Livingstone MB. Sarcopenia in premenopausal and postmenopausal women with osteopenia, osteoporosis and normal bone mineral density. Osteoporos Int. (2006)
  12. ^ Sørensen MB, et al. Obesity and sarcopenia after menopause are reversed by sex hormone replacement therapy. Obes Res. (2001)
  13. ^ a b Enns DL, Iqbal S, Tiidus PM. Oestrogen receptors mediate oestrogen-induced increases in post-exercise rat skeletal muscle satellite cells. Acta Physiol (Oxf). (2008)
  14. ^ Tiidus PM, Deller M, Liu XL. Oestrogen influence on myogenic satellite cells following downhill running in male rats: a preliminary study. Acta Physiol Scand. (2005)
  15. ^ Enns DL, Tiidus PM. Estrogen influences satellite cell activation and proliferation following downhill running in rats. J Appl Physiol. (2008)
  16. ^ Thomas A, Bunyan K, Tiidus PM. Oestrogen receptor-alpha activation augments post-exercise myoblast proliferation. Acta Physiol (Oxf). (2010)
  17. ^ a b Velders M, et al. Selective estrogen receptor-β activation stimulates skeletal muscle growth and regeneration. FASEB J. (2012)
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  53. Liu XX, et al. Effect of soy isoflavones on blood pressure: a meta-analysis of randomized controlled trials. Nutr Metab Cardiovasc Dis. (2012)
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  80. Taku K, et al. Extracted or synthesized soybean isoflavones reduce menopausal hot flash frequency and severity: systematic review and meta-analysis of randomized controlled trials. Menopause. (2012)
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  87. Jefferson WN, Williams CJ. Circulating levels of genistein in the neonate, apart from dose and route, predict future adverse female reproductive outcomes. Reprod Toxicol. (2011)
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