Expression of 11beta-hydroxysteroid dehydrogenase (11betaHSD) proteins in luteinizing human granulosa-lutein cells

in Journal of Endocrinology
Authors:
LM Thurston
Search for other papers by LM Thurston in
Current site
Google Scholar
PubMed
Close
,
E Chin
Search for other papers by E Chin in
Current site
Google Scholar
PubMed
Close
,
KC Jonas
Search for other papers by KC Jonas in
Current site
Google Scholar
PubMed
Close
,
IJ Bujalska
Search for other papers by IJ Bujalska in
Current site
Google Scholar
PubMed
Close
,
PM Stewart
Search for other papers by PM Stewart in
Current site
Google Scholar
PubMed
Close
,
DR Abayasekara
Search for other papers by DR Abayasekara in
Current site
Google Scholar
PubMed
Close
, and
AE Michael
Search for other papers by AE Michael in
Current site
Google Scholar
PubMed
Close
View More View Less
Free access

In a range of tIssues, cortisol is inter-converted with cortisone by 11beta-hydroxysteroid dehydrogenase (11betaHSD). To date, two isoforms of 11betaHSD have been cloned. Previous studies have shown that human granulosa cells express type 2 11betaHSD mRNA during the follicular phase of the ovarian cycle, switching to type 1 11betaHSD mRNA expression as luteinization occurs. However, it is not known whether protein expression, and 11betaHSD enzyme activities reflect this reported pattern of mRNA expression. Hence, the aims of the current study were to investigate the expression and activities of 11betaHSD proteins in luteinizing human granulosa-lutein (hGL) cells. Luteinizing hGL cells were cultured for up to 3 days with enzyme activities (11beta-dehydrogenase (11betaDH) and 11-ketosteroid reductase (11 KSR)) and protein expression (type 1 and type 2 11betaHSD) assessed on each day of culture. In Western blots, an immunopurified type 1 11betaHSD antibody recognized a band of 38 kDa in hGL cells and in human embryonic kidney (HEK) cells stably transfected with human type 1 11betaHSD. The type 2 11betaHSD antibody recognized a band of 48 kDa in HEK cells transfected with human type 2 11betaHSD cDNA but the type 2 protein was not expressed in hGL cells throughout the 3 days of culture. While the expression of type 1 11betaHSD protein increased progressively by 2.7-fold over 3 days as hGL cells luteinized, both 11betaDH and reductase activities declined (by 52.9% and 34.2%; P<0.05) over this same period. Changes in enzyme expression and activity were unaffected by the suppression of ovarian steroid synthesis.

 

  • Collapse
  • Expand