Escherichia coli derived factors modulate human granulosa cell steroidogenesis.
OBJECTIVE
In order to identify bacterial compounds which directly affect granulosa cell steroidogenesis, the effect of culture-supernatants and extracts from Escherichia coli were tested in an in vitro granulosa cell culture model.


METHODS
Samples were drawn from the culture-supernatant of E. coli ATCC25922 cultured in Luria-broth medium. Bacterial extract was prepared by incubation of freshly harvested bacteria in buffer. The bacterial culture-supernatants and extracts were added to human granulosa cells in culture. The granulosa cells collected from the follicular aspirates from women undergoing in-vitro fertilization were cultured for 17-53 h and progesterone or oestradiol was assayed in the spent culture medium.


RESULTS
The E. coli culture-supernatant stimulated the basal granulosa cell progesterone production demonstrating its maximum activity reached after 200-240 min of bacterial growth. The heat denaturated bacterial extract as well as its low-molecular-weight fraction (<10 kDa) stimulated both the basal and the hCG-stimulated progesterone production; the oestradiol production was slightly inhibited. Stimulation of progesterone production was time dependent increasing from 125 +/- 18% of control within the first 3 h to 205 +/- 35% within 17-53 h. The high-molecular-weight fraction (>30 kDa) of the bacterial extract inhibited progesterone production. The inhibitory activity was significantly diminished by heat denaturation.


CONCLUSIONS
The present study demonstrates the existence of various compounds which are secreted by E. coli and could also be extracted out of E. coli bacteria. These bacterial compounds modulate ovarian steroidogenesis. Further studies are needed to clarify how far these compounds contribute to menstrual disturbance observed in chronic pelvic inflammation.
Reinsberg
J
J
Department of Gynecological Endocrinology and Reproductive Medicine, University of Bonn, Bonn, Germany. jochen.reinsberg@ukb.uni-bonn.de
Christoffel
S
S
Kumar
A
A
van der Ven
H
H
D000328:Adult; D001426:Bacterial Proteins / Q000494:pharmacology*; D001431:Bacteriological Techniques; D002478:Cells, Cultured; D017077:Culture Media, Conditioned; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli; D004958:Estradiol / Q000378:metabolism; D005260:Female; D012739:Gonadal Steroid Hormones / Q000096:biosynthesis* / Q000378:metabolism; D006107:Granulosa Cells / Q000187:drug effects / Q000378:metabolism* / Q000382:microbiology*; D006801:Humans; D011374:Progesterone / Q000378:metabolism; D013268:Stimulation, Chemical; D013997:Time Factors
D001426:Bacterial Proteins; D017077:Culture Media, Conditioned; D012739:Gonadal Steroid Hormones; D011374:Progesterone; D004958:Estradiol