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Pharmacokinetic-pharmacodynamic study of subcutaneous injection of depot nandrolone decanoate using dried blood spots sampling coupled with ultrapressure liquid chromatography tandem mass spectrometry assays

Singh GK, Turner L, Desai R, Jimenez M, Handelsman DJ

J Clin Endocrinol Metab, 2014 Jul;99(7):2592-8.
PMID: 24684468 DOI: 10.1210/jc.2014-1243

Testosterone (T) and nandrolone (N) esters require deep im injections by medical personnel but these often deposit injectate into sc fat so that more convenient sc self-administration may be feasible.
Requirement for specific gravity and creatinine adjustments for urinary steroids and luteinizing hormone concentrations in adolescents

Singh GK, Balzer BW, Desai R, Jimenez M, Steinbeck KS, Handelsman DJ

Ann. Clin. Biochem., 2015 Nov;52(Pt 6):665-71.
PMID: 25780247 DOI: 10.1177/0004563215580385

Urinary hormone concentrations are often adjusted to correct for hydration status. We aimed to determine whether first morning void urine hormones in growing adolescents require adjustments and, if so, whether urinary creatinine or specific gravity are better adjustments.
Detrimental effects of bisphenol A on development and functions of the male reproductive system in experimental rats

Gurmeet K, Rosnah I, Normadiah MK, Das S, Mustafa AM

EXCLI J, 2014;13:151-60.
PMID: 26417249

Bisphenol A (BPA) is widely used in manufacturing industries. It is commonly detected in the environment and was reported to exert oestrogenic effects which may be harmful to the reproductive system. The present study was carried out to observe the effects of oral administration of BPA on the development of the reproductive organs and plasma sex hormone levels in prepubertal male Sprague-Dawley (SD) rats. Prepubertal male SD rats (n=8 in each group) were administered BPA in the doses of 1, 5, 10 and 100 mg/kg BW (body weight) via oral gavage for a period of 6 weeks. The control animals received the vehicle for BPA (Tween 80 in distilled water). Following 6 weeks of BPA exposure, the rats exhibited less evidence of spermatogenesis. There was seminiferous epithelial damage which included disruption of intercellular junctions and sloughing of germ cells into the seminiferous tubular lumen. Furthermore, the lumina of the seminiferous tubules and the epididymis of these animals were filled with immature germ cells and cellular debris. This damage may lead to the significant reduction in the seminiferous tubular diameter in BPA-treated animals. These findings were associated with the significant lower plasma testosterone and 17β-oestradiol levels. There was no significant difference between the body weight gain, the absolute as well as relative testis weight or epididymal weight of BPA-treated animals when compared to the control animals. The findings provided further evidence of the detrimental effects of BPA on the male reproductive system.
Fulltext Urinary Sex Steroids and Anthropometric Markers of Puberty - A Novel Approach to Characterising Within-Person Changes of Puberty Hormones

Singh GK, Balzer BW, Kelly PJ, Paxton K, Hawke CI, Handelsman DJ, et al.

PLoS One, 2015;10(11):e0143555.
PMID: 26599397 DOI: 10.1371/journal.pone.0143555

The longitudinal relationships of within-individual hormone and anthropometric changes during puberty have not ever been fully described. The objectives of this study were to demonstrate that 3 monthly urine collection was feasible in young adolescents and to utilise liquid chromatography-tandem mass spectrometry assay methods for serum and urine testosterone (T), estradiol (E2) and luteinizing hormone (LH) in adolescents by relating temporal changes in urine and serum hormones over 12 months to standard measures of pubertal development.
Fulltext Pharmacokinetics and Acceptability of Subcutaneous Injection of Testosterone Undecanoate

Turner L, Ly LP, Desai R, Singh GKS, Handelsman TD, Savkovic S, et al.

J Endocr Soc, 2019 Aug 01;3(8):1531-1540.
PMID: 31384715 DOI: 10.1210/js.2019-00134

Context: Can injectable testosterone undecanoate (TU) be administered effectively and acceptably by the subcutaneous (SC) route?
Objective: To investigate the acceptability and pharmacokinetics (PK) of SC injection of TU.
Design: Randomized sequence, crossover clinical study of SC vs IM TU injections.
Setting: Ambulatory clinic of an academic andrology center.
Participants: Twenty men (11 hypogonadal, 9 transgender men) who were long-term users of TU. injections. Intervention: Injection of 1000 mg TU (in 4 mL castor oil vehicle) by SC or IM route. Main Outcome Measures: Patient-reported pain, acceptability, and preference scales. PK by measurement of serum testosterone, dihydrotestosterone (DHT), and estradiol (E2) concentrations with application of population PK methods and dried blood spot (DBS) sampling.
Results: Pain was greater after SC compared with IM injection 24 hours (but not immediately) after injection but both routes were equally acceptable. Ultimately 11 preferred IM, 6 preferred SC, and 3 had no preference. The DBS-based PK analysis of serum testosterone revealed a later time of peak testosterone concentration after SC vs IM injection (8.0 vs 3.3 days) but no significant route differences in model-predicted peak testosterone concentration (8.4 vs 9.6 ng/mL) or mean resident time (183 vs 110 days). The PK of venous serum testosterone, DHT, and E2 did not differ according to route of injection.
Conclusions: We conclude that SC TU injection is acceptable but produces greater pain 24 hours after injection that may contribute to the overall majority preference for the IM injection. The PK of testosterone, DHT, or E2 did not differ substantially between SC and IM routes. Hence whereas further studies are required, the SC route represents an alternative to IM injections without a need to change dose for men for whom IM injection is not desired or recommended.