Flow chart of participant enrollment.

<p>Flow chart of participant enrollment.</p

Induction of necrosis in HESCs altered the secretion of HMGB-1.

Cell viability was detected by MTT assays after treatment of HESCs with H2O2 (A). Extracellular release of HMGB-1 was measured following H2O2-induced necrosis. Relative mRNA (B) and protein levels (C, D) are shown. *, P 2O2; **, P 2O2. a, fresh medium was used as a control; b, 0 μM H2O2; c, 25 μM H2O2; d, 50 μM H2O2.</p

Pathophysiology of Endometriosis: Role of High Mobility Group Box-1 and Toll-Like Receptor 4 Developing Inflammation in Endometrium

<div><p>Oxidative stress has been proposed as a potential factor associated with the establishment and progression of endometriosis. Although a few studies have shown possible mechanisms which may play roles in development, progression of endometriosis, few are known in regards of initiation of the disease, especially in the relationship with endometrium. The aim of our study was to investigate whether normal endometrium may be changed by Damage-associated molecular patterns (DAMPs), which may contribute developing pathologic endometrium to induce endometriosis. Endometrial tissues were obtained from 10 patients with fibroids undergoing hysterectomy at a university hospital. High mobility group box-1 (HMGB-1), which is a representative DAMP, has been chosen that may induce alteration in endometrium. In preceding immunohistochemistry experiments using paraffin-block sections from endometriosis (N = 33) and control (N = 27) group, retrospectively, HMGB-1 expression was shown in both epithelial and stromal cell. HMGB-1 expression was significantly increased in secretory phase of endometriosis group, comparing to the controls. To examine the alteration of endometrial stromal cell (HESC) by oxidative stress in terms of HMGB-1, cell proliferation and expression of its receptor, TLR4 was measured according to recombinant HMGB-1 use. Cell proliferation was assessed by CCK-8 assay; real-time PCR and western blotting were used to quantify Toll like receptor 4 (TLR4) mRNA and protein expression respectively. A TLR4 antagonist (LPS-RS) and an inhibitor of the NF-κB pathway (TPCA-1, an IKK-2 inhibitor) were used to confirm the relationships between HMGB-1, TLR4, and the NF-κB pathway. Passive release of HMGB-1 was significantly proportional to the increase in cell death (P<0.05). HESCs showed significant proliferation following treatment with rHMGB-1 (P<0.05), and increased TLR4 expression was observed following rHMGB-1 treatment (P<0.05) in a concentration-dependent manner. Treatment with a TLR4 antagonist and an NF-κB inhibitor resulted in suppression of rHMGB-1-induced HESC proliferation (P<0.05). Levels of IL-6 were significantly decreased following treatment with an NF-κB inhibitor (P<0.05). Our results support the development of altered, pathological endometrium resulted from oxidative stress in normal endometrium. These findings may provide important insights into the changes in endometrium linking the development and progression of endometriosis.</p></div

Immunohistochemistry analysis of HMGB-1 expression in the human endometrium.

<p>In control endometrium, HMGB-1 was expressed in the glandular cells of the epithelium and in stromal cells (N = 27). No significant differences were observed according to the menstrual cycle (A). In EM from a patient with endometriosis, significantly increased HMGB-1 expression was detected in the early and mid-secretory phase as compared to the control EM (N = 33, B). There were no significant differences in HMGB-1 expression between the two groups during the proliferative phase. *, <i>P</i> < 0.05 versus the control.</p

HESC proliferation and TLR4 expression were altered in a time-dependent manner after treatment with rHMGB-1.

<p>Changes in cell proliferation were measured at 0, 12, 24, and 48 h after treatment with 15 ng/mL rHMGB-1 (A). Relative mRNA (B) and protein levels (C, D) of TLR4 are shown. #, <i>P</i> < 0.05 versus 12 h; ##, <i>P</i> < 0.05 versus 24 h.</p

Effects of NF-κB inhibition on rHMGB-1-induced HESC proliferation and TLR4 expression.

<p>The NF-κB pathways was blocked using TPCA-1, and rHMGB-1-dependent cell proliferation was measured (A). TLR4 expression was analyzed using qRT-PCR (B) and western blotting (C, D) following treatment with different concentrations of rHMGB-1. Changes in IL-6 secretion were measured following inhibition of the NF-κB pathway by TPCA-1 (E). *, <i>P</i> < 0.05 versus the control.</p

BMD according to serum ferritin quartiles after adjusting with confounders in premenopausal and postmenopausal women.

<p>Only lumbar spine in premenopausal women showed significantly decreased tendency in BMD as serum ferritin increased in quartiles (P for trend = 0.035). On the other hand, BMD on total femur and femur neck (P for trend = 0.903, 0.890, respectively) in premenopausal women. BMD on total femur, femur neck, and lumbar spine in postmenopausal women were not found to be statistically significantly associated (P for trend = 0.396, 0.160, 0.793, respectively).</p

Effects of TLR4 inhibition on HESC proliferation and TLR4 expression following treatment with rHMGB-1.

<p>Cells were treated with the TLR4 antagonist LPS-RS, rHMGB-1-induced cell proliferation was measured (A). TLR4 mRNA and protein levels were measured (B–D). *, <i>P</i> < 0.05 versus the control.</p

HESC proliferation and TLR4 expression were altered in a concentration-dependent manner after treatment with rHMGB-1.

<p>At 48 h after treatment with different concentrations of rHMGB-1, cell proliferation was measured (A). Cell proliferation after 24 or 48 h of treatment with rHMGB-1 (B). Relative mRNA and protein levels of TLR4 are shown following treatment with rHMGB-1 (C, D). *, <i>P</i> < 0.05 versus the control; **, <i>P</i> < 0.05 versus 5 ng/mL rHMGB-1; ***, <i>P</i> < 0.05 versus 10 ng/mL rHMGB-1.</p

Logistic regression analysis to determine the effects of serum ferritin on bone mineral density at various skeletal sites.

<p>Adjusted variables: age, BMI, smoking, drinking, exercise, serum 25-hydroxyvitamin D levels, calcium and phosphate supplementations, personal history of fracture, family history of fracture.</p><p>Logistic regression analysis to determine the effects of serum ferritin on bone mineral density at various skeletal sites.</p