Background: It is unclear whether a short-term change in circulating androgens is associated with changes in the transcriptome of the peripheral blood mononuclear cells (PBMC).
Aims & Methods: To explore the effect of hCG-stimulation on the PBMC-transcriptome, 12 boys with a median age (range) of 0.7yrs (0.3, 11.2) who received intramuscular hCG 1500u on 3 consecutive days as part of their investigations underwent transcriptomic array analysis on RNA extracted from peripheral blood mononuclear cells before and after hCG stimulation.
Results: Median pre and post hCG testosterone for the overall group was 0.7nmol/l (<0.5,6) and 7.9nmol/l (<0.5, 31.5), respectively. Of the 12 boys, 3 (25%) did not respond to hCG stimulation with a pre and post median serum testosterone of <0.5nmol/l and <0.5nmol/l, respectively. When corrected for gene expression changes in the non-responders to exclude hCG effects, all 9 of the hCG responders consistently demonstrated a 20% or greater increase in the expression of piR-37153 and piR-39248, non-coding PIWI-interacting RNAs (piRNAs). In addition, of the 9 responders, 8, 6 and 4 demonstrated a 30%, 40% and 50% rise, respectively in a total of 2 further piRNAs. In addition, 3 of the responders showed a 50% or greater rise in the expression of another small RNA, SNORD5. On comparing fold change in serum testosterone with fold change in the above transcripts, a positive correlation was detected for SNORD5 (p=0.01).
Conclusions: The identification of a dynamic and androgen-responsive PBMC-transcriptome extends the potential value of the hCG test for assessment of androgen sufficiency
