Masashi Takamura

Recruitment of CCR6-Expressing Th17 Cells by CCL 20 Secreted from IL-1β-, TNF-α-, and IL-17A-Stimulated Endometriotic Stromal Cells

In a novel paradigm of T cell differentiation, type 17 T helper (Th17) cells may play a significant role in endometriosis, a chronic inflammatory disease. However, the mechanism regulating the accumulation of Th17 cells in endometriotic tissues remains unknown. We hypothesized that Th17 cells migrate to endometriotic tissues through an interaction of the chemokine CC chemokine ligand (CCL)20 and its receptor CCR6. Using endometriotic tissues from women with endometriosis, we demonstrated, by flow cytometry, that Th17 cells in endometriotic tissues express CC chemokine receptor (CCR)6. Immunohistochemistry also revealed that CCL20 was expressed in the epithelial cells and stromal cells beneath the epithelium of endometriotic tissues. CCR6+ cells were small and round and scattered in the stroma in which abundant CCL20+ cells were detected. CCL20 caused selective migration of Th17 cells in the peripheral blood in a migration assay. IL-1β, TNF-α, and IL-17A increased the secretion of CCL20 in cultured endometriotic stromal cells. Inhibitors of p38- and p42/44-MAPKs, and stress-activated protein kinase/c-Jun kinase suppressed the secretion of CCL20 increased by IL-1β, TNF-α, and IL-17A. This suggests that the CCL20/CCR6 system is involved in the migration of Th17 cells to endometriotic tissues and that proinflammatory cytokines contribute to the development of endometriosis via up-regulation of CCL20 secretion from endometriotic stromal cells.

Prevention of the recurrence of symptom and lesions after conservative surgery for endometriosis

Although surgical excision of endometriosis both improves pain and enhances fertility, recurrence can further exacerbate pain and reduce fertility, which in turn impacts the quality of life and increases personal as well as social costs. Therefore, it is crucial to prevent the recurrence of symptoms and lesions after conservative surgery. This article reviews evidence regarding the prevention of postoperative recurrence of endometriosis reported since the 1990s. Over the past 5 years, many new studies have been conducted and have demonstrated that long-term postoperative medication markedly reduces the recurrence. Most of these studies used oral contraceptives (OC), with either the cyclic or continuous regimen, while some used oral or intrauterine progestin. Continuous OC is more efficacious than cyclic OC, especially for dysmenorrhea. The levonorgestrel-releasing intrauterine system is also shown to prevent recurrence of dysmenorrhea and possibly endometriosis lesions. Dienogest, a new progestin, is shown to reduce the recurrence of endometrioma. Similar to the case of ovarian endometriosis, long-term postoperative medication after conservative surgery for deep infiltrating or extragenital endometriosis seems important, although data are limited. Regardless of the lesion and the medication type, patients who discontinued medication experienced a higher incidence of recurrence, indicating that the protective effect of these medications seems to vanish rapidly after the discontinuation. On the basis of these facts, together with the pathogenesis of recurrence (retrograde menstruation and ovulation), regular and prolonged medication until the patient wishes to conceive is highly recommended to prevent the postoperative recurrence of endometriosis.

Dienogest reduces proliferation, aromatase expression and angiogenesis, and increases apoptosis in human endometriosis

Abstract Dienogest is a novel progestin that is highly selective for progesterone receptors and inhibits endometriosis. However, it remains unknown how the administration of dienogest to patients with endometriosis impacts on their lesion tissues. The aim of this study was to evaluate the in vivo effect of dienogest on endometriosis tissue. We collected endometrioma tissues from patients treated with dienogest (N = 7) or not treated (N = 11, controls). Cell proliferation, aromatase expression and blood vessel density were evaluated by staining for Ki67, aromatase and the von Willebrand factor, respectively. Apoptosis was detected using the TUNEL assay. The proportion of Ki67 and aromatase positive epithelial cells was significantly lower in the dienogest group than in controls (p < 0.05, respectively). The number of TUNEL positive cells was significantly higher in the dienogest group (p < 0.05). The density of blood vessels in endometrioma was marginally lower in the dienogest group compared with controls (p = 0.20). Our study demonstrates that endometrioma taken from patients treated with dienogest show remarkable histological features such as reduction of proliferation, aromatase expression and angiogenesis, and increase of apoptosis. This study clarified the impact of dienogest on local histological events that explain its therapeutic effect on endometriosis. Chinese abstract 地诺孕素是一种新型的孕激素，具有孕激素受体高度选择性，可抑制子宫内膜异位症。但是，地诺孕素作用于内异症患者受损组织的机理现在仍未明确。本研究的目的在于评估地诺孕素在体内对子宫内膜异位组织的影响。我们采集经地诺孕素治疗（N = 7）与未经治疗（N = 11，对照组）的患者的子宫内膜异位组织。通过对Ki67染色、芳香化酶及von Willebrand因子的测定，评估细胞增殖、芳香化酶表达及血管密度。细胞凋亡情况通过TUNEL检验测定。结果显示，地诺孕素组的Ki67与芳香化酶阳性上皮细胞比例显著低于对照组（均为p < 0.05）。地诺孕素组的TUNEL阳性细胞数目显著高于对照组（p < 0.05）。地诺孕素组子宫内膜异位组织中血管密度略低于对照组（p = 0.20）。本研究结果表明，经地诺孕素治疗的子宫内膜异位症患者可出现显著的组织学特征改变，如降低细胞增殖、芳香化酶表达及血管生成减少及细胞凋亡增加。研究明确了地诺孕素对局部组织的影响，证实了其治疗子宫内膜异位症的效果。

Dienogest, a new conservative strategy for extragenital endometriosis: a pilot study

Extragenital endometriosis severely impairs the quality of life for affected women but its standard management has not yet been well established because of its relatively low incidence. As extragenital organs, intestine, followed by urinary tract, is the most common place affected by endometriosis, for which surgical treatment is sometimes difficult and accompanied by severe complications. Recently, dienogest, a novel progestin, has emerged as a new alternative for endometriosis, especially for endometriosis-associated pain. In this report, we presented four cases with rectosigmoidal and one with bladder endometriosis, treated with oral 2 mg/day dienogest for over 6 months. For all cases, the measurable extragenital lesions exhibited the reduction in their size after 10 to 11 months of use, accompanied with immediate relief of subjective symptoms related with extragenital lesions. This report suggests that dienogest can be a novel conservative alternative for extragenital endometriosis.

TGF-β1 induces proteinase-activated receptor 2 (PAR2) expression in endometriotic stromal cells and stimulates PAR2 activation-induced secretion of IL-6

BACKGROUND Proteinase-activated receptor 2 (PAR2) is a G-protein-coupled receptor that is activated by several serine proteases. PAR2 activation in endometriotic stromal cells (ESCs) has been implicated in the development of endometriosis but the regulatory mechanism of PAR2 expression in ESC is unknown. Our objective was to study the mechanism by which PAR2 expression may be regulated in endometriotic lesions. METHODS Primary cultures of ESCs were treated with transforming growth factor-β (TGF-β) 1, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), and the expression of PAR2 was examined by real-time quantitative PCR. ESCs pretreated with or without TGF-β1 were treated with PAR2 agonist peptide (PAR2AP) and the secretion of the pro-endometriotic cytokine, IL-6, was measured using a specific enzyme-linked immunosorbent assay. Effects of TGF-β type 1 inhibitor, SB431542, and PAR2 small interfering RNA (siRNA) on the TGF-β1 stimulation of PAR2 gene expression and PAR2AP-induced IL-6 secretion were also evaluated. To study intracellular signaling, effects of inhibitors of mitogen-activated protein kinases (MAPKs) and phosphoinositide 3-kinase (PI3K) and of Smad4 siRNA on the TGF-β1-induced PAR2 gene expression were studied. RESULTS Only TGF-β1, but neither TNF-α nor IL-1β, increased gene expression of PAR2. Activation of PAR2 with PAR2AP increased the secretion of IL-6 from ESCs. As expected, TGF-β1 pretreatment dose-dependently enhanced the PAR2AP-induced increase in IL-6 secretion from ESCs. Treatment of ESCs with the TGF-β type 1 inhibitor, SB431542, inhibited both TGF-β1-stimulation of PAR2 gene expression and PAR2AP-induced IL-6 secretion. Transfection of ESCs with PAR2 siRNA produced a similar inhibition of IL-6 secretion. The TGF-β1-induced increase in PAR2 gene expression was repressed by inhibition of p38 MAPK, p42/44 MAPK or PI3K, but not by knockdown of Smad4 expression. CONCLUSIONS In view of significant roles of PAR2 and IL-6 in endometriosis, the TGF-β1-induced increase in PAR2 expression may be an elaborate mechanism that augments the progression of the disease.

Interleukin-17F increases the secretion of interleukin-8 and the expression of cyclooxygenase 2 in endometriosis

OBJECTIVE To examine the effects of interleukin (IL)-17F on the secretion of IL-8 and the gene expression of cyclooxygenase 2 (COX2) in endometriotic stromal cells. DESIGN In vitro experimental study using human samples. SETTING University hospital. PATIENT(S) Endometriotic tissues were obtained from women with ovarian endometriomas undergoing laparoscopic surgery. INTERVENTION(S) Endometriotic stromal cells (ESCs) were cultured with IL-17F. MAIN OUTCOME MEASURE(S) Concentrations of IL-8 were measured by a specific ELISA, and messenger RNA levels of IL-8 and COX2 were measured by real-time reverse transcription-polymerase chain reaction (PCR). RESULT(S) IL-17F increased the secretion of IL-8 from ESCs, and the effect was inhibited by antibodies for IL-17 receptor A and IL-17 receptor C. Tumor necrosis factor α (TNF-α) synergistically enhanced IL-17F-induced increase in IL-8 secretion from ESCs. The IL-17F increased the gene expression of IL-8 and COX2 in ESCs. CONCLUSION(S) These findings suggest that IL-17F may stimulate the development of endometriosis by up-regulation of IL-8 and COX2.

Toll-Like Receptor-3 Ligation-Induced Indoleamine 2, 3-Dioxygenase Expression in Human Trophoblasts

Indoleamine 2,3-dioxygenase (IDO) is an enzyme that degrades an essential amino acid, tryptophan, and plays a role in inhibiting the proliferation of T cells and intracellular pathogens. Inhibiting IDO in mice leads to fetal rejection, suggesting its significance in establishing pregnancy. Toll-like receptor 3 (TLR-3) is a key component of the innate immune system that recognizes viral double-stranded RNA and triggers immune reactions by producing type I interferon. Using a human trophoblast cell culture system, we studied the effect of TLR-3 ligation on IDO expression and function by treating trophoblasts with polyinosinic-polycytidylic acid [poly(I:C)] (a synthetic double stranded RNA, which mimics viral RNA). Real-time PCR and Western blot analysis revealed that IDO mRNA and protein expression was significantly induced by poly(I:C). The activity of IDO was also increased by poly(I:C) given that the L-kynurenine concentrations were elevated in conditioned media. Conditioned media from poly(I:C)-treated trophoblasts were found to inhibit the proliferation of human T cells significantly. Poly(I:C) was also shown to induce interferon (IFN)-β mRNA expression in trophoblasts. Recombinant human IFN-β increased IDO mRNA expression in trophoblasts more rapidly than poly(I:C). Pretreating with neutralizing antibody against IFN-β significantly suppressed IDO induction by poly(I:C). Collectively we have demonstrated that ligation of TLR-3 by poly(I:C) induces IDO expression in human first-trimester trophoblasts via an IFN-β-dependent pathway. These findings suggest that upon viral infection, trophoblasts induce IDO and in turn contribute to antimicrobial activity and maintenance of fetomaternal tolerance.

Effects of 1,25-Dihydroxy Vitamin D3 on Endometriosis

CONTEXT Endometriosis is an estrogen-dependent, chronic inflammatory disease. Recent studies have shown that vitamin D (VD) is an effective modulator of the immune system and plays an important role in controlling many inflammatory diseases. OBJECTIVE The objective of the study was to clarify the in vitro effects of 1,25-dihydroxy vitamin D3 (1,25[OH]2D3) on human endometriotic stromal cells (ESCs) and to determine the serum levels of VD in endometriosis patients. DESIGN, PATIENTS, AND MAIN OUTCOME MEASURES ESCs were isolated from ovarian endometrioma and cultured with 1,25(OH)2D3. Gene expression of IL-8, cyclooxygenase-2, microsomal prostaglandin E synthase-1, microsomal prostaglandin E synthase-2, cytosolic prostaglandin E synthase, 15-hydroxyprostaglandin dehydrogenase, matrix metalloproteinase (MMP)-2, and MMP-9 was examined using quantitative RT-PCR. The production of IL-8 and prostaglandin E2 was measured using an ELISA and an enzyme immunoassay. Viable cell number was assessed using a cell-counting assay, and DNA synthesis was assessed using the bromodeoxyuridine incorporation assay. Apoptosis was assessed using flow cytometry. The expression of inhibitory-κBα protein was detected using Western blotting. The serum levels of 25-hydroxyvitamin D3 and 1,25(OH)2D3 were measured by a RIA. RESULTS In vitro studies showed that 1,25(OH)2D3 significantly reduced IL-1β- or TNF-α-induced inflammatory responses, such as IL-8 expression and prostaglandin activity. 1,25(OH)2D3 also reduced viable ESC numbers and DNA synthesis but did not affect apoptosis. MMP-2 and MMP-9 expressions were reduced by 1,25(OH)2D3. 1,25(OH)2D3 inhibited nuclear factor-κB activation. The serum 25-hydroxyvitamin D3 levels were significantly lower in women with severe endometriosis than in the controls and women with mild endometriosis. Serum 1,25(OH)2D3 levels were not different between groups. CONCLUSIONS VD modulates inflammation and proliferation in endometriotic cells, and a lower VD status is associated with endometriosis. Taken together, VD supplementation could be a novel therapeutic strategy for managing endometriosis.

Interleukin-1β stimulates the secretion of thymic stromal lymphopoietin (TSLP) from endometrioma stromal cells: possible involvement of TSLP in endometriosis

STUDY QUESTION Is thymic stromal lymphopoietin (TSLP) involved in the pathophysiology of endometriosis? SUMMARY ANSWER TSLP is up-regulated by interleukin (IL)-1β and may be involved in the development of endometriosis. WHAT IS KNOWN ALREADY Endometriosis is a chronic inflammatory disease in which the Th2 immune response is activated and has been suggested to promote the disease. TSLP is a master cytokine that drive Th2 immune response. STUDY DESIGN, SIZE, DURATION A laboratory study. PARTICIPANTS/MATERIALS, SETTING, METHODS Primary cultures of endometrioma stromal cells (ESCs) were treated with IL-1β, a typical inflammatory cytokine associated with endometriosis. Gene expression of TSLP in ESCs and secretion of TSLP protein from ESCs were studied using quantitative PCR and a specific ELISA. Interferon γ (IFNγ), a typical Th1 cytokine, and IL-4, a typical Th2 cytokine, were added to the culture to evaluate their effect on the IL-1β-induced secretion of TSLP. Inhibitors of p38 mitogen-activated protein kinase (MAPK), p42/44 MAPK and stress-activated protein kinase/Jun amino-terminal kinase (SAPK/JNK) were added to the culture to examine intracellular signals involved in IL-1β-induced TSLP secretion. The expression of TSLP in endometrioma tissue was examined by immunohistochemistry. The concentration of TSLP in the serum and peritoneal fluid (PF) of women with or without endometriosis was measured with a specific ELISA. MAIN RESULTS AND THE ROLE OF CHANCE IL-1β stimulated the expression of TSLP mRNA and secretion of TSLP protein from ESCs. IL-4 enhanced the IL-1β-induced TSLP secretion from ESCs, while IFNγ reduced it. Inhibitors of p42/44 MAPK, p38 MAPK and SAPK/JNK suppressed the IL-1β-induced secretion of TSLP from ESCs. Positive immunostaining of TSLP was observed in the stroma of endometrioma tissue. TSLP concentrations in the serum and PF were both higher in women with endometriosis compared with those without endometriosis. LIMITATIONS, REASONS FOR CAUTION The present study was only in vitro. The samples used for culture were endometrioma tissues, not including other types of endometriosis. Therefore, the present findings should be interpreted with caution. WIDER IMPLICATIONS OF THE FINDINGS This study provided new insights in the Th2 immune response-related mechanism in endometriosis. STUDY FUNDING This study is partly supported by grants from the Ministry of Health, Labour and Welfare, and the Ministry of Education, Culture, Sports, Science and Technology. The authors have no conflicts of interest to declare.

Progesterone decreases bone morphogenetic protein (BMP) 7 expression and BMP7 inhibits decidualization and proliferation in endometrial stromal cells

BACKGROUND Regulation of decidualization is decisive for proper implantation and the establishment of pregnancy. Recent studies have suggested that several bone morphogenetic proteins (BMPs) play physiological roles in reproduction. In the present study, we examined the expression of BMP7 in the endometrium and the effect of BMP7 on decidualization and proliferation of endometrial stromal cells (ESC). METHODS The gene expression of BMP7 in endometrial tissues collected from women with regular menstrual cycles was determined and the effect of ovarian steroid hormones on BMP7 gene expression was investigated in cultured ESC. The effect of BMP7 on the decidualization of ESC was determined by measuring the gene expression and protein secretion of insulin-like growth factor binding protein 1 (IGFBP1), a marker of decidualization. The effect of BMP7 on the proliferation of ESC was examined by the bromodeoxyuridine (BrdU) incorporation assay. RESULTS The gene expression of BMP7 in endometrial tissues was low at and after the mid-secretory phase of the menstrual cycle. Progesterone suppressed the gene expression of BMP7 in cultured ESC. Treatment with progesterone and estradiol for 12 days achieved decidualization of ESC, increasing the gene expression and protein secretion of IGFBP1. Addition of BMP7 protein to the culture almost completely inhibited these increases. BMP7 suppressed BrdU incorporation in ESC, which indicated an antiproliferative effect of BMP7 on ESC. CONCLUSIONS Progesterone-induced suppression of BMP7 and BMP7-induced inhibition of decidualization and proliferation of ESC suggest an elaborate regulatory mechanism for decidualization through BMP7 in the endometrium.