Exp Mol Med.  2003 Jun;35(3):160-166.

Expression of 3b-Hydroxysteroid dehydrogenase and P450 side chain cleavage enzyme in the human uterine endometrium

• Rhee HS
• Oh SH
• Ko BJ
• Han DM
• Jeon BH
• Park H
• Moon HB
• Kim WS

Abstract

The enzyme complex 3b-hydroxysteroid dehydrogenase/delta(5)-delta(4)-isomerase (3beta-HSD) is involved in the biosynthesis of all classes of active steroids. The expression of 3beta-HSD in human uterine endometrium during the menstrual cycle and decidua was examined in an effort to understand its role during ova implantation. 3beta-HSD was weakly expressed in the glandular epithelium of the proliferative phase and moderately expressed in the glandular epithelium of secretory phase of the endometrium. In the decidua of the ectopic pregnancy, 3beta-HSD was strongly expressed. The human uterine endometrial 3beta-HSD was identified as being the same type as the placental 3beta-HSD by RT-PCR and sequence analysis. In addition to the expression of 3beta-HSD, P450scc was expressed in the decidua of the ectopic pregnancy. These results suggest that pregnenolone might be synthesized from cholesterol by P450scc de novo and then, it is converted to progesterone by 3beta-HSD in the uterine endometrium. The data implies that the endometrial 3beta-HSD can use not only the out-coming pregnenolone from the adrenal gland but also the self- made pregnenolone to produce progesterone. The de novo synthesis of progesterone in the endometrium might be a crucial factor for implantation and maintenance of pregnancy.

Keyword

3 beta-HSD; decidua; P450scc; progesterone; uterine endometruium

MeSH Terms

Cholesterol/chemistry
Cholesterol Side-Chain Cleavage Enzyme/*biosynthesis/genetics
Decidua/enzymology
Endometrium/*enzymology
Female
Gene Expression/physiology
Human
Menstrual Cycle/physiology
Multienzyme Complexes/*biosynthesis/genetics
Placenta/enzymology
Pregnancy
Pregnenolone/biosynthesis
Progesterone/biosynthesis
Progesterone Reductase/*biosynthesis/genetics
Steroid Isomerases/*biosynthesis/genetics