Sports Medicine Australia Young Investigator Award: Natural killer cell numbers and natural killer cytotoxic activity after six weeks of testosterone enanthate administration in healthy young males
Markshall-Gradisnik, SM, Rogerson, S, Deakin, GB, Coutts, RA, Meir, RA, Zhou, S & Weatherby, RP 2005, 'Sports Medicine Australia Young Investigator Award: Natural killer cell numbers and natural killer cytotoxic activity after six weeks of testosterone enanthate administration in healthy young males', Medicine & Science in Sports & Exercise, vol. 38, no. 5 supplement, p. 74.
PURPOSE: Androgenic-anabolic steroids (AAS) are beneficial for athletic performance (Giorgi et al., 1999). However, there is a paucity of literature that has examined the role of AAS, in particular, testosterone enanthate (TE), on immune function.
METHODS: Fifteen healthy young males (mean age 24.8 ± 5.2) were randomly assigned in a double blind method to either a 3.5mg/kg TE (mean age 24.8 ± 5.1; n = 8) or placebo (mean age 26.1 ± 3.4; n = 7) weight training (WT) group. The study was conducted over six weeks and acute immune variables were assessed at week 0 (W0) and week 6 (W6), both before and immediately after a 10-seoncd cycle test. T lymphocyte numbers, Natural Killer cell numbers (NKCN) and Natural Killer Cytotoxic Activity (NKCA) were assessed using flow cytometry.
RESULTS: NKCA significantly increased for the placebo group from W0 to W6 [24.1 ± 4.6 (W0), 33.4 ± 3.9(W6)]. There was a reduction in NKCA for the TE group from W0 to W6 [18.9 ± 3.5 (W0); 13.8 ± 5.4 (W6)] and a significant difference between groups for NKCA at W6 (TE 13.8 ± 5.4, P 33.4 ± 3.9). There was no significant difference between groups for T-lymphocyte numbers for the six week study.
CONCLUSION: The results from this study indicates AAS may adversely affect immune function. Consequently athletes may be more susceptible to illness and highlights the potential adverse health affects of the use of AAS. Additionally, the role of TE on lymphocyte proliferation needs further investigation. Giorgi, A., et al. (1999). J Sci Med Sport. 2(4): 341-55. Support: Mentorn Television Corporation, London, UK