Research group - Lena Ekström

We are performing studies on doping and drug metabolism.

We study how different doses and administration routes of doping agents, genetic variations, gender, diseases, and co-medications can affect the results of doping tests. We have shown that individuals that are devoid of the UGT2B17 gene (and enzyme) do not excrete testosterone in the urine to the same extent as those with UGT2B17 allele(s) and may therefore escape a testosterone doping test. Moreover, the urinary biomarker for testosterone doping miss to detect testosterone intake in women. Elite athletes test results may be longitudinal monitored in an athlete biological passport (ABP) that calculates individual thresholds. Our studies have shown that the individual ABP thresholds are larger in women due to hormonal fluctuation during the menstrual cycle. Pregnancy and contraceptives are confounders that may the interpretation of ABP results.

Future testing strategy may include blood sampling to monitor serum testosterone (and other steroids) levels. Ongoing studies are conducted to see how testosterone serum levels are affected by doping and natural confounders in women. We are studying additional steroid-metabolites i.e., sulfate conjugates in urine and serum to see if inclusion of these may improve the chances to detect testosterone doping.

We are investigating the possibility to use dried blood spots (DBS) as a matrix for steroid and erythropoietin (EPO) detection, and if the esterified steroids often abused in the society (among recreational athletes) can be detected in serum and DBS.

In addition to improve detection of doping substances, we are studying side effects (cardiovascular and endocrine parameters) of anabolic-androgenic steroids (AAS). This is done in healthy volunteers (low, single dose administration of AAS) and in self-reporting AAS users, in collaboration with Anti-Doping. We are also mapping what AAS as well as other anabolic agents such as SARMs are popular to use in the society (by self-reports and presence in urine samples).

Research group leader Lena Ekström

Profile image

Lena Ekström

Adjunct Professor

Group members

PhD students (main supervisor)

Licentiate students (main supervisor)

Alexander Andersson

Kim Pettersson-Bohlin

Research techniques

  • Genotyping
  • Quantitative PCR (gene expression, miRNA)
  • Western blot
  • LC-MS/MS and GC-MS/MS

External funding

Swedish National Centre for Research in Sports, Partnership for clean competition (PCC).

Teaching assignments

Pharmacology, 7.5 Credits, semester 6, BMA.

Selected publications

Studies of athlete biological passport biomarkers and clinical parameters in male and female users of anabolic androgenic steroids and other doping agents.
Börjesson A, Lehtihet M, Andersson A, Dahl ML, Vicente V, Ericsson M, Ekström L
Drug Test Anal 2020 Apr;12(4):514-523

Longitudinally monitoring of P-III-NP, IGF-I, and GH-2000 score increases the probability of detecting two weeks' administration of low-dose recombinant growth hormone compared to GH-2000 decision limit and GH isoform test and micro RNA markers.
Lehtihet M, Bhuiyan H, Dalby A, Ericsson M, Ekström L
Drug Test Anal 2019 Mar;11(3):411-421

Urinary steroid profile in relation to the menstrual cycle.
Schulze J, Suominen T, Bergström H, Ericsson M, Björkhem Bergman L, Ekström L
Drug Test Anal 2021 Mar;13(3):550-557

Sensitivity of doping biomarkers after administration of a single dose testosterone gel.
Mullen J, Börjesson A, Hopcraft O, Schulze JJ, Ericsson M, Rane A, Lehtihet M, Ekström L
Drug Test Anal 2018 May;10(5):839-848

Recruitment to doping and help-seeking behavior of eight female AAS users.
Börjesson A, Gårevik N, Dahl ML, Rane A, Ekström L
Subst Abuse Treat Prev Policy 2016 Mar;11():11