A botanical extract from channel flow inhibits cell proliferation, induces apoptosis, and suppresses CCL5 in human endometriotic stromal cells.

Growing evidence suggests that medicinal herbs have direct actions on endometrial cells. By screening multiple herbs using an in vitro model of endometriosis, we found that a commonly used herbal formula exerted considerable antiproliferative effects. Our purpose was to investigate the effects of this antiendometriosis herbal mixture on cell proliferation, apoptosis, and CCL5 expression and secretion in endometriotic stromal cells in vitro. Isolated normal endometrial, eutopic, and ectopic endometriotic stromal cells were cultured under established conditions. Cell proliferation, apoptosis, and CCL5 gene expression protein secretion was evaluated after incubation with different concentrations of an antiendometriosis herbal mixture extract. Cell proliferation was assessed by cell counting, (3)H-thymidine incorporation, and MTS assays. Apoptosis was determined by blotting using anti-cleaved caspase 3 antibodies and by a TUNEL assay. CCL5 gene expression and protein secretion were determined by transient transfection of gene promoter reporters and ELISAs in cell supernatants. Extracts of a traditional herbal mixture dose-dependently decreased cell proliferation in normal, eutopic, and ectopic endometriotic stromal cells. (3)H-Thymidine uptake and MTS confirmed these findings. The herbal extracts induced apoptosis, as evidenced by activation of caspase 3 and the presence of TUNEL-positive cells after treatment. The herbal extracts also suppressed CCL5 gene transcription and protein secretion in endometriotic stromal cells, even when corrected for cell number. Extracts from a medicinal herbal mixture have direct effects on cell proliferation, apoptosis, and CCL5 production in endometriotic stromal cells. Our findings support the further investigation of novel, potentially safe and well-tolerated botanical products as future endometriosis treatments.

Natural and recombinant human glycodelin activate a proapoptotic gene cascade in monocyte cells.

Glycodelin-A (GdA) is a member of the superfamily of lipocalins and the predominant glycoprotein secreted by human and primate endometrium in the secretory and early pregnancy phases. GdA can inhibit NK cell activity, T cell proliferation, and chemotaxis of monocytes. Its physiological function is thought to mediate immunotolerance at the fetomaternal interface. In the present studies, we engineered recombinant Gd (rGd) in yeast and tested its biological effects on monocyte viability. rGd, like the natural, purified endometrial GdA, is glycosylated and secreted, and they both induced apototic changes in monocytic U937 cells and primary human monocytes. Trypan blue exclusion, nucleosome release, DNA laddering, and immunocytochemistry to detect free 3'-OH DNA ends were used to characterize the effects of GdA and rGd. Using U937 cells as a model, cDNA microarray analyses revealed several pro- and antiapoptotic genes that were up- and down-regulated, respectively, in accordance with the kinetics of rGd-induced monocyte cell death. Real-time RT-PCR confirmed that Bad, Bax, and TNF-R1 gene expression were increased, whereas Bcl-2A1 and a proliferation-inducing ligand (APRIL) were reduced by rGd. Transfection assays in U937 cells indicated that the immunomodulatory actions of rGd were associated with NF-kappaB inhibition. Western blotting of U937 and primary monocyte lysates demonstrated that rGd activated caspase-8, -2, and -3 to execute programmed cell death in these cells. We postulate that infiltrating monocytes and potentially other innate immune cells of the decidua might be manipulated by this glycoprotein to enhance embryonic implantation rates or conversely, to develop novel contraceptive strategies.

Translin coactivates steroidogenic factor-1-stimulated transcription.

Transcription of the rat P450c17 gene in Leydig cells requires steroidogenic factor-1 (SF-1) (NR5A1), nerve growth factor-inducible protein B (nurr77), COUP-TF, and SET. The -447/-419 region of this promoter contains two binding sites for orphan nuclear receptors that are required for activation by SF-1, nerve growth factor-inducible protein B, and cAMP. We identified a novel factor, steroidogenic factor-inducer of transcription-2, that binds to this -447/-419 region. We have now purified steroidogenic factor-inducer of transcription-2 from mouse Leydig MA-10 cells and identified it by mass spectrometry as translin, a 27-kDa protein that exerts many functions. By itself, translin cannot activate a P450c17-promoter/reporter construct in HeLa cells; however, translin increased SF-1-stimulated transcription 2-fold, indicating cooperativity between SF-1 and translin. Mutation of both SF-1 binding sites in the -447/-419 sequence eliminated activation by SF-1 and translin. Translin did not augment SF-1-stimulated transcription from all SF-1-responsive elements, suggesting that the activation is specific for the sequence of the SF-1 response element. Gel shift analysis of double- and single-stranded DNA showed that translin binds to single-stranded DNA, but its transcriptional activation is independent of DNA binding. The hinge region of SF-1 is necessary for activation by translin; deletion of hinge amino acids 170-225 in SF-1 eliminates translin's ability to augment SF-1-dependent transcription. A translin-like protein, called translin-associated factor X, can substitute for a translin moiety; translin homomers and translin/translin-associated factor X heteromers activated SF-1-stimulated transcription equally. Thus, we have identified a new factor that works together with SF-1 to augment gene transcription in a DNA-specific fashion.

All-trans retinoic acid inhibits vascular endothelial growth factor expression in a cell model of neutrophil activation.

Infiltrating neutrophil granulocytes are a particularly rich source of vascular endothelial growth factor (VEGF) in the endometrium and may contribute to the angiogenesis of endometriosis lesions. The objective of this study is to evaluate the expression and regulation of VEGF in endometrial neutrophils and in a model of neutrophil differentiation relevant to endometriosis. Immunohistochemistry was performed on endometriosis patient biopsies and cultured neutrophil-like HL-60 cells were assessed. The study was set in a reproductive biology division within an academic medical center. Endometrial biopsies were performed on women with endometriosis and HL-60 cells were treated with all-trans retinoic acid (atRA) and dimethyl sulfoxide in vitro. Immunofluorescence histochemistry, VEGF mRNA and protein quantification, and transfection studies of VEGF gene promoter-luciferase constructs were all main outcome measures. Immunofluorescence studies verified the presence of neutrophils in eutopic endometrium from women with endometriosis. Examination of the regulation of VEGF using differentiated HL-60 cells as a model, revealed that atRA induced a dose- and time-dependent suppression of VEGF mRNA and protein. Transient transfection, truncation, EMSA, and site-directed mutagenesis of human VEGF promoter-luciferase constructs in HL-60 cells indicated that atRA repressed VEGF gene transcription via a direct repeat 1 element located between -443 and -431 bp relative to the transcription initiation site. Because retinoic acid is synthesized de novo in endometrial cells under the influence of progesterone, our findings suggest that the up-regulated VEGF and angiogenesis in tissue from women with endometriosis may reflect failure of neutrophil differentiation in these cases, and provide a rationale for retinoid therapy in this condition.

Sulindac suppresses nuclear factor-kappaB activation and RANTES gene and protein expression in endometrial stromal cells from women with endometriosis.

CONTEXT: The nuclear factor-kappaB (NF-kappaB) pathway is a critical mediator of RANTES (regulated on activation, normal T cell expressed and secreted) gene regulation and therefore represents a potential target for therapy of endometriosis-associated symptoms. OBJECTIVE: The objective of this study was to investigate the effects of the antiinflammatory drug sulindac on NF-kappaB activation, NF-kappaB-mediated gene expression, RANTES gene and protein expression in endometrial stromal cells isolated from women with endometriosis, and unaffected controls. DESIGN: This was a clinical experimental study. SETTING: The study was conducted at a university hospital. RESULTS: The inflammatory response in endometriosis is augmented by a 5-fold increased TNFalpha-induced RANTES secretion from ectopic endometriotic stromal cells, compared with normal endometrial stromal cells (P < 0.05). Western blot analysis revealed basal activation of NF-kappaB in endometriotic cells, which could be suppressed by sulindac. EMSAs showed that sulindac dramatically decreased NF-kappaB activation and diminished TNFalpha and IL-1beta-induced NF-kappaB DNA binding activity. Sulindac pretreatment resulted in a significant decrease in TNFalpha-induced luciferase activity of NF-kappaB response element and -477 bp RANTES promoter constructs in normal and endometriotic stromal cells. The addition of sulindac to IL-1beta- and TNFalpha-treated endometriotic stromal cells also resulted in a 4-fold inhibition of RANTES protein secretion (P < 0.05). CONCLUSIONS: We have demonstrated that sulindac exerts strong antiinflammatory effects by suppression of NF-kappaB translocation, inhibition of NF-kappaB-mediated gene transcription, RANTES gene expression, and protein secretion in normal and endometriotic stromal cells. These results suggest that drugs targeting the NF-kappaB pathway may be beneficial in the treatment of endometriosis-associated symptoms.

Effects of phorbol dibutyrate on cell proliferation, apoptosis, and tumor necrosis factor-alpha expression in human endometrial adenocarcinoma cells.

OBJECTIVES: Recent evidence suggested that protein kinase C (PKC), a major cell cycle regulator in endometrial models, mimics progesterone withdrawal by inducing downstream signals. In the current study we examined the hypothesis that the PKC activator phorbol 12,13 dibutyrate (PDB) would inhibit cell proliferation and induce apoptosis in two endometrial adenocarcinoma cell (EAC) lines, HEC-1B and Ishikawa cells. We further examined whether the induction of tumor necrosis factor-alpha (TNF-alpha) might mediate these effects. METHODS: EAC lines were cultured under standard and serum-free conditions to study the effects of PDB on cell kinetics. Cell proliferation was determined by cell count using a hemacytometer and by incorporation of (3)H thymidine into 10% trichloracetic acid-precipitable DNA. Apoptosis was determined by measuring cytoplasmic histone-associated DNA fragments. Conditioned media concentrations of TNF-alpha were measured by a commercially available enzyme-linked immunosorbent assay (ELISA). EACs were transfected with a -125-bp TNF-alpha promoter luciferase construct and treated with PDB to evaluate transcriptional activation. RESULTS: Activation of the PKC system with PDB (10 nM) decreased cell proliferation and mitogenesis in EACs. PDB induced apoptosis in both EAC lines. EACs exhibit basal TNF-alpha gene expression and protein secretion and these were increased potently by PDB. However, neutralization of TNF-alpha by addition of anti-TNF-alpha antibodies did not prevent the suppression of mitogenesis, induction of apoptosis, or activation of TNF-alpha gene expression by PDB. CONCLUSION: Activation of the PKC system leads to inhibition of cell proliferation, induction of apoptosis, and TNF-alpha expression in EACs. However, apoptosis in this setting does not appear to require TNF-alpha action. EACs provide an informative model to investigate aspects of endometrial epithelial remodeling that may occur under physiologic conditions of progesterone withdrawal.

2,3,7,8-Tetrachlorodibenzo-p-dioxin increases glycodelin gene and protein expression in human endometrium.

CONTEXT: Glycodelin (GdA) is an immunosuppressive endometrial glycoprotein critical for embryonic implantation and pregnancy establishment. OBJECTIVE: The aim of the present study was to examine the effect of dioxin [2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)] on GdA production in human endometrial cells. DESIGN: Controlled endometrial explant (EE) and cell cultures were used in this study. SETTING: Work was conducted at university hospital research laboratories in Bern, Switzerland, and in San Francisco, California. PATIENTS: Ovulatory women provided endometrial biopsies in the proliferative or secretory phase. INTERVENTION(S): EEs and cells were cultured without and with TCDD. MAIN OUTCOME MEASURE(S): GdA protein and gene expression were quantified. RESULTS: A 2.5-fold increase in GdA production was demonstrated in EEs treated with 10 nm TCDD for 9 d. Fluorography revealed a 3- to 4-fold increase in new GdA biosynthesis and secretion in TCDD-treated endometrial epithelial cells. Because the action of dioxin is mediated by the aryl hydrocarbon receptor (AhR), we ascertained that primary epithelial and Ishikawa cells express AhR. Dose responses to TCDD and expressed AhR were established in transiently transfected Ishikawa cells using luciferase fusion vectors containing 1.0 kb of 5' flanking DNA relative to the GdA transcriptional start site but not when shorter promoter constructs were used. A dioxin response element was mapped to nucleotides -539 to -533 of the gene promoter and verified by site-directed mutagenesis. CONCLUSIONS: We demonstrated a direct AhR-mediated effect of dioxin on GdA gene transcription and protein secretion that might influence human female fertility.

PPAR gamma represses VEGF expression in human endometrial cells: implications for uterine angiogenesis.

UNLABELLED: Endometrial vasculature supports physiological uterine growth, embryonic implantation and endometrial pathology. Vascular endothelial growth factor (VEGF) is regulated by diverse developmental and hormonal signals, including eicosanoid ligands of PPARgamma. The action of natural and synthetic PPARgamma ligands on VEGF expression in primary and transformed human endometrial cell cultures was established by quantifying endogenous gene expression and transfected VEGF gene reporters. VEGF promoter-luciferase constructs were truncated and mutated to map functional sequences. Endometrial tissues and cells express PPARgamma protein. Treatment of transformed and primary endometrial cells with rosiglitazone, a synthetic PPARgamma agonist, or prostaglandin 15-deoxy-Delta12-14 J(2), a naturally occurring eicosanoid ligand, decreased VEGF protein secretion. In transiently transfected Ishikawa cells, rosiglitazone repressed VEGF gene promoter-luciferase activation with an IC(50) approximately approximately 50 nM. Truncated and mutated VEGF promoter constructs revealed that the PPARgamma-regulated domain is a direct repeat (DR)-1 motif -443 bp upstream of the transcriptional start site. CONCLUSIONS: PPARgamma ligands repress VEGF gene expression via a PPARgamma-responsive element (PPRE) in the VEGF gene promoter. Agonists of this nuclear receptor might be exploited pharmacologically to inhibit pathological vascularization in complications of pregnancy, endometriosis and endometrial adenocarcinoma.

Thiazolidinedione inhibition of peritoneal inflammation.

Chemoattraction of macrophages into the peritoneal cavity is one of the important characteristics in patients with endometriosis. An inflammatory response is postulated to be responsible for infertility and pelvic pain associated with this syndrome. The present in vivo studies were designed to test if thiazolidinediones (TZDs), activators of peroxisome proliferator activated receptor gamma, could inhibit monocyte chemotaxis in a murine model. TZDs were first used as orally bioavailable insulin-sensitizing agents. They are currently under investigation in the treatment of inflammatory diseases, including arthritis or colitis. Intraperitoneal injection of thioglycollate was used to elicit high numbers of activated peritoneal macrophages in female mice. Concomitant peritoneal injection of ciglitazone, a member of the TZD family, significantly reduced the number of macrophages. When cultured and stimulated by tumor necrosis factor alpha, these peritoneal macrophages also secreted less RANTES and less IL-1beta protein. This animal model suggests that treatment of endometriosis patients with TZDs may diminish symptoms associated with intraperitoneal inflammation.

Progestins activate vascular endothelial growth factor gene transcription in endometrial adenocarcinoma cells.

OBJECTIVE: To determine whether progestins activate vascular endothelial growth factor (VEGF) gene transcription in endometrial adenocarcinoma cells. DESIGN: In vitro study. SETTING: University reproductive biology laboratories. PATIENT(S): None. INTERVENTION(S): Ishikawa cells were transfected with VEGF promoter-luciferase reporter constructs and expression vectors encoding human progesterone receptors (hPR) A or B. The cells were treated with different progestins and antiprogestins, and luciferase activity was compared with controls. MAIN OUTCOME MEASURE(S): Three functional progesterone response elements (PREs) in the VEGF promoter were identified by electrophoretic mobility-shift assay, and different constructs were created to assess each PRE. RESULT(S): In cells expressing hPRA or B, treatment with 10 nM R5020 or 100 nM medroxyprogesterone acetate statistically significantly increased luciferase activity (3.3- to 4.8-fold). Pretreatment with 100 nM RU486 blunted the effect of 10 nM R5020, resulting only in a slight, statistically nonsignificant increase in luciferase activity (1.3- to 1.7-fold). Although three different functional PREs could be identified, no single PRE accounted for the preponderance of the luciferase activity. Full VEGF promoter activation required all three PREs. CONCLUSION(S): Progestins have a direct effect on VEGF gene transcription. However, hPR-mediated transcriptional regulation of the VEGF promoter is complex and cannot be localized to confined PRE sequences. Other response element motifs are likely to play a contributory role.