17β-Estradiol as a Neuroprotective Agent

Purpose: The purpose of this study was to analyze the effects of estrogen deficiency and hormone replacement therapy (HRT) on fibrinolytic activity in a rat mode of surgically-induced menopause. Methods: Twelve-week-old, sexually mature female Sprague-Dawley rats, each weighing 200–250 g, were randomly divided into four groups: (1) sham-operated group, (2) ovariectomy group, (3) ovariectomy group followed by oral administration of daily 17β-estradiol (0.02 mg/kg/day) (E2) + norethisterone acetate (0.01 mg/kg/day), and (4) ovariectomy group followed by oral administration of daily 17β-estradiol (0.01 mg/kg/day) + drospirenone (0.02 mg/kg/day). Tissue plasminogen activator (tPA) antigen, plasminogen activator inhibitor-1 (PAI-1) antigen, and PAI-1/tPA levels were measured as markers of fibrinolysis in plasma and liver and brain tissue. Results: Compared with sham-operated rats, ovariectomized rats showed higher levels of fibrinolytic activity; however, the increased fibrinolytic activity in plasma and liver tissue was significantly reduced by HRT regimens. No change was observed in the levels of fibrinolytic activity in brain tissue. Conclusions: HRT showed beneficial effects by decreasing fibrinolytic activity related to surgically-induced menopause. Short-term HRT treatment was associated with a shift in the procoagulant-anticoagulant balance toward a procoagulant state.

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A Surface Plasmon Resonance Based Inhibition Immunoassay for Sensitive and Selective Detection of 17β-Estradiol

10.26434/chemrxiv.5945005 ◽

2018 ◽

Author(s):

Yong Cao ◽

Mark T. McDermott

Keyword(s):

Surface Plasmon Resonance ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Quantitative Measurement ◽

Dynamic Range ◽

Indirect Detection ◽

Negative Slope ◽

Chip Surface ◽

Detection Mechanism ◽

17Β Estradiol

<div> <div> <div> <p>Quantitative measurement of small-molecule metabolites is now emerging as an effective way to link the metabolite profile to disease state. Surface plasmon resonance (SPR) is a sensing platform that has demonstrated applicability for a large range of biomolecules. However, direct detection of small molecules with SPR challenges the refractive index based detection mechanism. Herein, we utilized an indirect detection format and developed an inhibition immunoassay for the quantitative measurement of 17β-estradiol (E2) using SPR. One competitor, BSA-E2 conjugate, was immobilized to the SPR chip via the reaction between the primary amino group of the conjugate and the succinimide group (NHS) introduced by the formation of a thiol-NHS monolayer on gold surface. Free E2 molecules compete with BSA-E2 on chip surface for binding sites provided by a monoclonal anti-E2 antibody. It was found the binding affinity of the antibody to BSA-E2 conjugate increases with decreasing surface coverage of BSA-E2 conjugate. Under optimal conditions, a sigmoidal calibration curve with a negative slope and a dynamic range from 10 pM to 2 nM was generated. The detection limit of the immunoassay is estimated to be 0.3 pM. Moreover, the immunoassay exhibits high specificity for E2 detection using estrone (E1) as a potential interference.</p></div></div></div>

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