Forskning
Udskriv Udskriv
Switch language
Region Hovedstaden - en del af Københavns Universitetshospital
Udgivet

Hallmarks of Human Small Antral Follicle Development: Implications for Regulation of Ovarian Steroidogenesis and Selection of the Dominant Follicle

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

DOI

  1. Biological and Clinical Rationale for Androgen Priming in Ovarian Stimulation

    Publikation: Bidrag til tidsskriftReviewForskningpeer review

  2. Glycemic Variability and Diabetic Neuropathy in Young Adults With Type 1 Diabetes

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

  1. Expression of the Insulin-like Growth Factor System in First- and Second-Trimester Human Embryonic and Fetal Gonads

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

  2. Futures and fears in the freezer: Danish women's experiences with ovarian tissue cryopreservation and transplantation

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

  3. Shortcomings of an unphysiological triggering of oocyte maturation using human chorionic gonadotropin

    Publikation: Bidrag til tidsskriftReviewForskningpeer review

Vis graf over relationer

Regulation of human ovarian steroidogenesis differs from other species and precise knowledge on how human small antral follicles (hSAF) develop and acquire competence for continued growth and steroid output is still incomplete. The present study has characterized almost 1,000 normal hSAF collected in connection with cryopreservation of ovarian tissue for fertility preservation. The antral follicles (ranging from 3 to 13 mm) were generally aspirated from one ovary surgically removed during the natural cycle, and the follicular fluid (FF) and the granulosa cells (GC) were isolated and snap-frozen. In FF, the following hormones were measured: inhibin-B, inhibin-A, AMH, follistatin, PAPP-A, estradiol, progesterone, testosterone, and androstenedione. In GC, mRNA gene expressions using q-PCR were measured for the following genes: FSHR, AMH, CYP19, and AR. All samples in which one of the abovementioned parameters was measured were included, but typically multiple parameters were measured. Highly significant differences in concentration and follicular content in relation to follicular diameter were found for all measured hormones despite massive variability in-between follicles for any given diameter. The results demonstrate that profound changes take place in the hormonal microenvironment around follicular diameters of 8-11 mm corresponding to when follicular selection occurs. At this point, inhibin-B and inhibin-A showed distinct peaks concomitant with a significant reduction in both AMH protein and mRNA expression. Concentrations of inhibins, androgens, FSHR, and AR were intimately associated, and it is suggested that inhibin-B in combination with PAPP-A and thereby IGF2 activity exerts important paracrine signaling at follicular selection. At the same time upregulation of estradiol synthesis and CYP19 mRNA expression increased steroid output profoundly. Furthermore, the highly significant association between FSHR and AR mRNA gene expression enforces important functions of androgens in follicular development. Collectively, these data reintroduce the understanding of the follicular phase as two parted in which regulation of steroidogenesis differs. The profound changes taking place around follicular selection highlight important paracrine actions of TGF-β family members and IGFs for securing dominance of the selected follicle.

OriginalsprogEngelsk
TidsskriftFrontiers in Endocrinology
Vol/bind8
Sider (fra-til)376
ISSN1664-2392
DOI
StatusUdgivet - 2018

ID: 52661114