Metabolomics of testosterone enanthate administration during severe-energy deficit

Abstract

Introduction: Testosterone administration attenuates reductions in total body mass and lean mass during severe energy deficit (SED).

Objectives: This study examined the effects of testosterone administration on the serum metabolome during SED.

Methods: In a double-blind, placebo-controlled clinical trial, non-obese men were randomized to receive 200-mg testosterone enanthate/wk (TEST) (n = 24) or placebo (PLA) (n = 26) during a 28-d inpatient, severe exercise- and diet-induced energy deficit. This study consisted of three consecutive phases. Participants were free-living and provided a eucaloric diet for 14-d during Phase 1. During Phase 2, participants were admitted to an inpatient unit, randomized to receive testosterone or placebo, and underwent SED for 28-d. During Phase 3, participants returned to their pre-study diet and physical activity habits. Untargeted metabolite profiling was conducted on serum samples collected during each phase. Body composition was measured using dual-energy X-ray absorptiometry after 11-d of Phase 1 and after 25-d of Phase 2 to determine changes in fat and lean mass.

Results: TEST had higher (Benjamini-Hochberg adjusted, q < 0.05) androgenic steroid and acylcarnitine, and lower (q < 0.05) amino acid metabolites after SED compared to PLA. Metabolomic differences were reversed by Phase 3. Changes in lean mass were associated (Bonferroni-adjusted, p < 0.05) with changes in androgenic steroid metabolites (r = 0.42-0.70), acylcarnitines (r = 0.37-0.44), and amino acid metabolites (r = - 0.36-- 0.37). Changes in fat mass were associated (p < 0.05) with changes in acylcarnitines (r = - 0.46-- 0.49) and changes in urea cycle metabolites (r = 0.60-0.62).

Conclusion: Testosterone administration altered androgenic steroid, acylcarnitine, and amino acid metabolites, which were associated with changes in body composition during SED.

Keywords: Anabolic; Military stress; Semi-starvation; Sport metabolomics.

Fig. 1

Experimental design transformed from Pasiakos et al.,

Fig. 2

Total testosterone concentrations between testosterone and placebo conditions. * p < 0.01, **p < 0.001. Time points represent after 14-d of the free-living, controlled feeding (CON), 14- (SED14) and day 28-d (SED28) of severe energy deficit, 14-d of free-living, ad libitum feeding (FL), and weight-regain (WR)

Fig. 3

PCA scores plot during controlled feeding (Phase 1), after 14- and 28-days of severe energy deficit (Phase 2), and after 14-days of free-living and weight regain (Phase 3)

Fig. 4

Heatmap of significant group x time interactions in response to severe energy deficit and testosterone administration. Data were clustered by Ward’s clustering with the Euclidean distance. Time points represent after 14-d of the free-living, controlled feeding (CON), 14- (SED14) and day 28-d (SED28) of severe energy deficit, 14-d of free-living, ad libitum feeding (FL), and weight-regain (WR). AC acylcarnitine metabolites, AC,DC acylcarnitine, dicarboxylate metabolites, AP Acetylated Peptides, AS Androgenic Steroids, BFA branch fatty acid, BM Benzoate metabolites, CA Ceramides, CH Chemical, CM creatine metabolites, FCP Food Component/Plant, GAA Gamma-glutamyl Amino Acid, GSTM Glycine, Serine and Threonine metabolites, HCER Hexosylceramides, HIS Histidine metabolites, HPM Hemoglobin and Porphyrin metabolites, LIV Leucine, Isoleucine and Valine metabolites, LM Lysine metabolites, LP Lysophospholipid, MCFA Medium Chain Fatty Acid, MCST Methionine, Cysteine, SAM and Taurine metabolites, MG Monoacylglycerol, MUFA Long Chain Monounsaturated Fatty Acid, NNM Nicotinate and Nicotinamide metabolites, PAM Polyamine metabolites, PBAM Primary Bile Acid metabolites, PCM Partially Characterized Molecules, PE Phosphatidylethanolamine, PHE Phenylalanine metabolites, PLM Phospholipid metabolites, PM Pentose metabolites, PN Vitamin B6 metabolites, PUFA Long Chain Polyunsaturated Fatty Acid, PYM Pyrimidine metabolites, SFA Long Chain Saturated Fatty Acid, TRP Tryptophan metabolites, TY Tyrosine metabolites, UAP Urea cycle; Arginine and Proline metabolites

Fig. 5

Heatmap of Pearson’s correlation coefficients between changes in analytes and changes in fat mass (top) and lean mass (bottom) after severe energy-deficit