Postmenopausal estrogen therapy and serum estradiol fatty acid esters in women with and without previous intrahepatic cholestasis of pregnancy.
BACKGROUND
Fatty acid esters of 17beta-estradiol (E2) are estrogen metabolites associated with lipoproteins in blood.


OBJECTIVE
To study the effects of estrogen therapy on concentrations of serum E2 fatty acid esters in postmenopausal women with a history of an estrogen-related liver disorder, intrahepatic cholestasis of pregnancy (ICP), and in healthy women in a double-blind, crossover fashion.


METHODS
ICP (n = 10) and control women (n = 10) received increasing doses of E2 valerate orally 2-4 mg/day, or transdermal E2 50-100 microg/day for 6 weeks. After a 4-week wash-out period, the subjects crossed over to the alternate E2 treatment. Concentrations of serum E2 fatty acid esters were quantified after saponification by fluoroimmunoassay.


RESULTS
Oral E2 administration increased median serum E2 fatty acid ester concentrations from 57 to 73 pmol/L in the ICP and from 56 to 74 pmol/L in the control group, in association with elevations in serum E2, estrone and sex hormone-binding globulin levels. Transdermal E2 treatment did not increase serum E2 ester levels.


CONCLUSIONS
The increase in serum E2 fatty acid esters during oral E2 administration may be attributed, at least partly, to the higher estrogen dose during oral compared with transdermal therapy. A history of ICP did not affect esterification of E2 during estrogen therapy.
Department of Medicine, Helsinki University Central Hospital, Helsinki, Finland.
Veera
V
Vihma
Anne
A
Ropponen
Kristiina
K
Aittomäki
Olavi
O
Ylikorkala
Matti J
MJ
Tikkanen
D016022:Case-Control Studies; D002780:Cholestasis, Intrahepatic / Q000150:complications; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004952:Esters; D004958:Estradiol / Q000097:blood* / Q000737:chemistry / Q000378:metabolism; D015914:Estrogen Replacement Therapy; D004967:Estrogens / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D005227:Fatty Acids / Q000737:chemistry; D005260:Female; D015200:Fluoroimmunoassay; D006801:Humans; D050356:Lipid Metabolism; D008055:Lipids / Q000097:blood; D017698:Postmenopause / Q000097:blood* / Q000187:drug effects / Q000378:metabolism; D011247:Pregnancy; D012738:Sex Hormone-Binding Globulin / Q000187:drug effects
D004952:Esters; D004967:Estrogens; D005227:Fatty Acids; D008055:Lipids; D012738:Sex Hormone-Binding Globulin; D004958:Estradiol