Research Paper Volume 10, Issue 5 pp 902—929
Testosterone and dihydrotestosterone reduce platelet activation and reactivity in older men and women
- 1 Department of Haemostatic Disorders, Medical University, Lodz, Poland
- 2 Department of Pharmaceutical Chemistry, Medical University of Gdansk, Gdansk, Poland
- 3 Department of Geriatrics, Healthy Ageing Research Centre (HARC), Medical University, Lodz, Poland
Received: November 11, 2017 Accepted: April 26, 2018 Published: May 2, 2018
https://doi.org/10.18632/aging.101438How to Cite
Copyright: Karolczak et al. This is an open‐access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Abstract
The cardiovascular effects of testosterone and dihydrotestosterone are generally attributed to their modulatory action on lipid and glucose metabolism. However, no ex vivo studies suggest that circulating androgen levels influence the activation and reactivity of blood platelets – one of the main components of the haemostasis system directly involved in atherosclerosis. The levels of testosterone, dihydrotestosterone and oestradiol in plasma from men and women aged from 60 to 65 years were measured by LC-MS; the aim was to identify any potential relationships between sex steroid levels and the markers of platelet activation (surface membrane expression of GPII/IIIa complex and P-selectin) and platelet reactivity in response to arachidonate, collagen or ADP, monitored with whole blood aggregometry and flow cytometry. The results of the ex vivo part of the study indicate that the concentrations of testosterone and its reduced form, dihydrotestosterone are significantly negatively associated with platelet activation and reactivity. These observations were confirmed in an in vitro model: testosterone and dihydrotestosterone significantly inhibited platelet aggregation triggered by arachidonate or collagen. Our findings indicate that testosterone and dihydrotestosterone are significant haemostatic steroids with inhibitory action on blood platelets in older people.