| First Author | Li R | Year | 2017 |
| Journal | Reprod Fertil Dev | Volume | 29 |
| Issue | 12 | Pages | 2430-2436 |
| PubMed ID | 28531375 | Mgi Jnum | J:258384 |
| Mgi Id | MGI:6111922 | Doi | 10.1071/RD17100 |
| Citation | Li R, et al. (2017) Mouse minipuberty coincides with gonocyte transformation into spermatogonial stem cells: a model for human minipuberty. Reprod Fertil Dev 29(12):2430-2436 |
| abstractText | As the transient postnatal hormone surge in humans, known as ''minipuberty'', occurs simultaneously with key steps in germ-cell development, we investigated whether similar changes occur in the hypothalamic-pituitary-testicular axis of neonatal mice at a time that would coincide with gonocyte transformation into spermatogonial stem cells (SSC). Serum and testes were collected from C57Bl/6 mice at embryonic Day 17 (E17), birth (postnatal Day 0; P0) and daily until P10. Serum FSH and testosterone levels in both serum and testes were analysed and gene expression of FSH receptor (Fshr), luteinising hormone receptor (Lhr), anti-Mullerian hormone (Amh), octamer-binding transcription factor 4 (Oct-4), membrane type 1 metalloprotease (Mt1-mmp), proto-oncogene C-kit and promyelocytic leukaemia zinc finger (Plzf ) was quantified by real-time polymerase chain reaction. We found a transient surge of serum and testicular testosterone levels between P1 and P3 and a gradual increase in FSH from P1 to P10. Testis Lhr expression remained low from P0 until P10 but Fshr expression peaked between P3 and P6 (P<0.01). The same was found for Oct-4 expression (a gonocyte marker), which surged between P3 and P6 (P<0.01). Mt1-mmp expression peaked at P3 (P<0.05). The expression pattern of both C-kit and Plzf (SSC markers) was similar with a steady increase from P1 to P10. These results show a transient activation of the hypothalamic-pituitary-testicular axis postnatally with increases in serum and testicular testosterone at P1-P3 and testicular Fshr (but not Lhr) at P3-P6. These changes coincide with increases in gene expression of Oct4, Mt1-mmp, Plzf and C-kit, reflecting gonocyte activation, migration and transformation into SSC. In conclusion, these findings suggest that ''minipuberty'' does occur in mice and that gonocyte transformation may be driven by a transient FSH signalling pathway. |
