Common 677C-->T mutation of the 5,10-methylenetetrahydrofolate reductase gene affects follicular estradiol synthesis.
OBJECTIVE
To investigate the influence of the 5,10-methylenetetrahydrofolate reductase 677C-->T mutation on the E(2) synthesis in human granulosa cells (GCs).


METHODS
In vitro cell culture study.


METHODS
Research laboratory of a university hospital.


METHODS
Follicular fluids (n = 139) and GCs (n = 66) were obtained from patients undergoing controlled ovarian hyperstimulation for IVF with or without ICSI.


METHODS
Granulosa cells were cultured for a total of 5 days. On day 3, the cells either were stimulated with recombinant (r-) FSH or r-LH (80 IU/L for 48 h) or were sham stimulated.


METHODS
Estradiol and protein content were measured in the pooled follicular fluids of each individual. At the end of each GC-culturing period, the concentrations of E(2) were measured in the supernatants of triplicate cultures by immunoassays. The 5,10-methylenetetrahydrofolate reductase 677C-->T genotype was determined by RFLP analysis.


RESULTS
The E(2)-protein ratio of homozygous T/T carriers was significantly lower compared with that of homozygous C/C individuals. Furthermore, basal and r-FSH- as well as r-LH-stimulated E(2) synthesis of GC obtained from homozygous T/T patients was significantly reduced, compared with GC from heterozygous C/T and homozygous C/C subjects.


CONCLUSIONS
Decreased E(2) in follicular fluid and decreased E(2) synthesis of GC from homozygous T/T individuals suggest that reduced follicular E(2) is a result of impaired E(2) production of human GC.
Hecht
Stephanie
S
Department of Obstetrics and Gynecology, Division of Endocrinology and Reproductive Medicine, Grosshadern, Ludwig Maximilians-University, Munich, Germany.
Pavlik
Roman
R
Lohse
Peter
P
Noss
Ulrich
U
Friese
Klaus
K
Thaler
Christian J
CJ
D000328:Adult; D003596:Cytosine; D004958:Estradiol / Q000096:biosynthesis*; D005260:Female; D005298:Fertility / Q000502:physiology; D015571:Follicular Fluid / Q000502:physiology; D005838:Genotype; D006801:Humans; D007258:Informed Consent; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D006080:Ovarian Follicle / Q000502:physiology*; D020641:Polymorphism, Single Nucleotide; D011446:Prospective Studies; D013941:Thymine; D055815:Young Adult
D004958:Estradiol; D003596:Cytosine; D042965:Methylenetetrahydrofolate Reductase (NADPH2); D013941:Thymine