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Estrogen Therapy


Scientists believe that estrogen may be neuroprotective, which would explain why pre-menopausal women have a lower incidence of Parkinsonís disease than do post-menopausal women who are not on estrogen replacement therapy,  and why  men have a higher incidence than women.

While there is no proven mechanism for estrogenís neuroprotection , one theory is that it may inhibit mitochondrial failure and oxidative stress thought to play a part in Parkinsonís disease. Scientists believe estrogen prevents cell death in large measure by ensuring that mitochondrial membranes remain functionally intact. Cells that are protected from sudden mitochondrial failure are also protected from the gradual mitochondrial dysfunction associated with Parkinsonís disease.[1]

Because estrogenís anti-oxidative abilities protect the brain, estrogen deprivation is likely to initiate or enhance degenerative changes caused by oxidative stress. Oxidative stress reduces the brain's ability to maintain synaptic connectivity, leading to the cognitive decline seen in individuals who are  elderly and disease-afflicted.[2]

Potential benefits:

  • Neuroprotection

  • Slower disease progression

  • Anti-oxidative abilities

  • Improved cognitive function


  • Estrogen combined with levodopa is sometimes associated with dyskinesias

  • Higher incidence of  uterine cancer

  • Blood clots

  • Nausea

  • Edema

  • Weight gain


  • Oral treatments in men may produce unwanted feminizing side effects

Current research:

  • MIGENIX:   MX-4509

MIGENIXís 17a-estradiol sodium sulfate (ď17a-estradiolĒ), designated MX-4509, is being considered for the treatment of neurodegenerative diseases associated with mitochondrial failure, including Alzheimerís disease, Parkinsonís disease, and Friedreichís ataxia. This estrogen compound should be suitable for chronic treatment of degenerative diseases in both men and women because it has minimal feminizing consequences.[4]

  • POETRY study

The Parkinson Study Group (PSG) is conducting a study in postmenopausal women with Parkinsonís Disease to measure the safety and tolerability of estrogen replacement therapy (ERT). The study includes how ERT affects daily activities, thinking and behavior, and motor fluctuations and dyskinesias. Thirty participants will be enrolled at six US sites. Enrollment began in 2003.[5]


[1] Mitochondria Play a Central Role in Estrogen-Induced Neuroprotection, James W. Simpkins, Jian Wang, Xiaofei Wang, Evelyn Perez, Laszlo Prokai and James A. Dykens, Current Drug Targets - CNS & Neurological Disorders, Volume 4, No. 1, 2005

[2] Estrogen and neurodegeneration - Gandy S; Neurochem Res 2003 Jul;28(7):1003-8.

[3] NINDS: Estrogen Information Summary; Last updated October 06, 2004

[4] SEC Form 20-F; Sept 17, 2004; MIGENIX, INC., Retrieved date: 9/26/04

[5] Parkinson Study Group; Retrieved date: 9/26/04

Copyright© 2012 Pipeline Project

All rights reserved. Revised: 01/26/12.