[P3.068] Neuroprotection by Sex Steroid Hormones in Parkinson's Disease
Kara M. Smith, Nabila Dahodwala
Philadelphia, PA, USA
OBJECTIVE: To systematically review the relationship between sex steroid hormones and neuroprotection in Parkinson's Disease (PD).
BACKGROUND: Sex is a major contributor to the risk of developing PD, with a relative risk of 1.5 in males compared to females, and estrogen may account for this difference. It has been shown that the risk of PD is lower in women with more lifetime estrogen exposure including hormone replacement therapy. Animal studies suggest that estrogen maintains the dopaminergic system and may be neuroprotective in PD. We performed a systematic review of the role of estrogen and other sex steroid hormones in PD.
DESIGN/METHODS: A Pubmed search was performed for English articles between Jan 1980 and Dec 2013. A search for Parkinson(s) and sex/gender differences yielded 238 results, and Parkinson(s) and estrogen, or selective estrogen receptor modulator, yielded 104 new articles. Studies were selected if they focused on neuroprotection by sex steroid hormones in PD.
79 articles were selected for inclusion. 31 articles described the effects of 17β-estradiol on markers of dopaminergic integrity in neurotoxin-mediated animal models of PD. 27 of these 31 demonstrated neuroprotection of markers including dopamine, DOPAC, HVA, DAT and VMAT2 mRNA and specific binding. There were fewer studies investigating other estrogen compounds, although estradiol benzoate and progesterone may be neuroprotective. Selective estrogen receptor modulators appear to be neuroprotective based on 10/13 positive studies. Androgens do not appear to be neuroprotective based on 6 studies.
The neuroprotective effects of sex steroid hormones vary by hormone and sex. The quantity and consistency of the articles reviewed are highly suggestive that estrogen, specifically 17β-estradiol, is neuroprotective in toxin-mediated animal models of PD. 17β-estradiol has high affinity for the estrogen receptor, suggesting the protective effects are receptor-mediated. Harnessing the neuroprotective effects of estogren is a promising therapeutic path in PD prevention and treatment.
Category - Movement Disorders: Parkinson's Disease
Tuesday, April 29, 2014 3:00 PM
P3: Poster Session III: Movement Disorders: Clinical Features of Parkinson's Disease (3:00 PM-6:30 PM)