Anti-Müllerian Hormone (AMH) Induces Aromatase Expression in Human Granulosa Cells – A study

Objective: Anti-Müllerian Hormone (AMH) is aDesign: Effects of AMH in the absence and
member of the transforming growth factor-?presence of cAMP were studied in primary
(TGF-?) family. Within the ovary AMH is producedluteinized hGCs obtained during in vitro fertilization
solely by granulosa cells and plays an importantcycles and in the immortalized human granulosa
role in regulation of ovarian follicle growth. Incell line, HGL5.
mouse ovary, AMH has been found to inhibitMaterials and Methods: hGCs were cultured +/-
recruitment of primordial follicles into the pool ofdibutyryl cAMP (1 mM), +/- AMH (5-100 ng/ml)
growing follicles and decreases the sensitivity offor 24-48h. RNA was isolated,
small pre-antral follicles to FSH. Along with itsreversed-transcribed and real-time PCR was
pivotal role in follicular development, AMH servesperformed to measure mRNA transcripts for
as a putative marker of ovarian reserve and ofaromatase containing the ovary-specific first exon
assisted reproductive technology outcome.(CYP19IIa) and for AMH.
Aromatase cytochrome P450 (encoded by theResults: In HGL5 cells, cAMP caused a ~40-fold
CYP19 gene) is the key enzyme in theinduction of CYP19IIa mRNA. While AMH (25 ng
biosynthesis of estrogens from C19-steroidml) alone had a modest stimulatory effect
precursors. Previous animal studies have shown(~1.5-fold), co-treatment with AMH + cAMP
that AMH inhibits the expression of aromatase incaused a synergistic ~75-fold increase in CYP19IIa
fetal ovaries; however, the effect of AMH onmRNA levels. In primary cultures of hGCs, basal
aromatase in postnatal human ovaries is not wellCYP19IIa mRNA levels were elevated; cAMP
understood. The objective of the present studycaused a ~2.5-fold increase in CYP19IIa mRNA,
was to investigate the effects of AMH on thewhile AMH had a moderate stimulatory effect
expression of aromatase in human granulosa cells(1.5-fold). In cells co-treated with AMH + cAMP,
(hGCs).CYP19IIa mRNA levels were increased ~3.5-fold.