title: Hyperandrogenism Decreases GRP78 Protein Level and Glucose Uptake in Human Endometrial Stromal Cells.
abstract: Women with polycystic ovary syndrome (PCOS) exhibit a low fertility by chronic hyperandrogenemia. Different evidence have shown that androgens could regulate the endoplasmic reticulum (ER) homeostasis and glucose metabolism. However, it is unclear whether androgens can exert these effects on human endometrial stromal cells. Our goal was to study the protein content of GRP78 (an ER homeostasis marker) in endometria from women with PCOS and healthy women and to assess the GRP78 protein levels and its relationship with glucose uptake on a human endometrial stromal cell line stimulated with testosterone.
  
  
  
  Immunohistochemistry assays for GRP78 were performed on endometrial samples obtained from women with PCOS (n = 8) and control women subjected to hysterectomy (n = 8). Western blot analysis for GRP78 and glucose uptake was assessed in a telomerase-immortalized human endometrial stromal cell line (T-HESC) exposed to testosterone for 24 or 48 hours and challenged to an insulin short-term stimulation. Tukey test was performed for human samples comparison. Student t test or ANOVA-Bonferroni test was carried out according to the in vitro experiment. P < .05 was considered as significant.
  
  
  
  GRP78 stromal immunostaining was reduced in PCOS endometria compared to controls (P < .05). The T-HESC shows a testosterone-dependent downregulation of GRP78 protein content (P < .05), concomitant with half-reduction in glucose uptake compared to controls (P < .05). Moreover, enhanced small interfering RNA against GRP78 messenger RNA leads to a decrease in glucose uptake (P < .05). Such effects were reverted by hydroxyflutamide, an inhibitor of androgen receptor.
  
  
  
  These results suggest that hyperandrogenemic PCOS environment could compromise the endometrial homeostasis confirmed by the decrease in glucose uptake induced by testosterone and exhibited by stromal cells.
authors.affiliation: Laboratory of Endocrinology and Reproductive Biology, University of Chile Clinical Hospital, Santiago, Chile.
authors.forename: Carlos
authors.initials: C
authors.lastname: Rosas
authors.affiliation: Laboratory of Endocrinology and Reproductive Biology, University of Chile Clinical Hospital, Santiago, Chile.
authors.forename: Lorena
authors.initials: L
authors.lastname: Oróstica
authors.affiliation: Laboratory of Endocrinology and Reproductive Biology, University of Chile Clinical Hospital, Santiago, Chile.
authors.forename: Cristian
authors.initials: C
authors.lastname: Poblete
authors.affiliation: Laboratory of Endocrinology and Reproductive Biology, University of Chile Clinical Hospital, Santiago, Chile Department of Obstetrics and Gynecology, University of Chile Clinical Hospital, Santiago, Chile.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Carvajal
authors.affiliation: Faculty of Medicine, University of Chile, Santiago, Chile.
authors.forename: Fernando
authors.initials: F
authors.lastname: Gabler
authors.affiliation: Laboratory of Endocrinology and Reproductive Biology, University of Chile Clinical Hospital, Santiago, Chile Department of Obstetrics and Gynecology, University of Chile Clinical Hospital, Santiago, Chile.
authors.forename: Carmen
authors.initials: C
authors.lastname: Romero
authors.affiliation: Faculty of Medicine, University of Chile, Santiago, Chile Advanced Center for Chronic Diseases (ACCDIS), Faculty of Chemical & Pharmaceutical Sciences, University of Chile, Santiago, Chile Advanced Center for Chronic Diseases (ACCDIS), Faculty of Medicine, University of Chile, Santiago, Chile.
authors.forename: Sergio
authors.initials: S
authors.lastname: Lavandero
authors.affiliation: Laboratory of Endocrinology and Reproductive Biology, University of Chile Clinical Hospital, Santiago, Chile Department of Obstetrics and Gynecology, University of Chile Clinical Hospital, Santiago, Chile Faculty of Medicine, University of Chile, Santiago, Chile mvega@med.uchile.cl.
authors.forename: Margarita
authors.initials: M
authors.lastname: Vega
mesh_terms: D000328:Adult; D002460:Cell Line; D004717:Endometrium / Q000187:drug effects / Q000378:metabolism*; D000091342:Endoplasmic Reticulum Chaperone BiP; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006801:Humans; D017588:Hyperandrogenism / Q000378:metabolism*; D011085:Polycystic Ovary Syndrome / Q000378:metabolism*; D017154:Stromal Cells / Q000187:drug effects / Q000378:metabolism; D013739:Testosterone / Q000008:administration & dosage / Q000502:physiology*; D055815:Young Adult
chemical_list: D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D013739:Testosterone; D005947:Glucose
keywords: ER stress; GRP78; endometrium; glucose; testosterone