Inverse correlation between peritoneal fluid leptin concentrations and the extent of endometriosis

BACKGROUND: The role of leptin in reproductive processes has received increasing attention. Because leptin has intrinsic angiogenic properties, may be induced by inflammatory cytokines and induces matrix metalloproteinases, we examined peritoneal fluid (PF) leptin concentrations in women with endometriosis. METHODS: PF samples were collected from 60 women undergoing laparoscopy for endometriosis, and 18 controls undergoing tubal sterilization. Fifty of the women with endometriosis had received no prior hormonal treatment, while 10 with moderate- severe endometriosis were using GnRH agonists. RESULTS: Women with untreated endometriosis had significantly higher (mean +/- SD) PF leptin levels (34.9 +/- 7.9 ng/ml) than controls (17.9 +/- 4.1 ng/ml; P < 0.001). However, PF leptin levels were inversely correlated with the stage of disease (r = -0.62; P < 0.001). Nevertheless, women with stage III-IV endometriosis maintained significantly higher PF leptin levels (26.3 +/- 4.8 ng/ml; P < 0.001) than controls. Although PF leptin levels were significantly higher in the secretory versus proliferative phase of the menstrual cycle, they remained higher in both phases in women with untreated endometriosis. PF leptin levels in women on GnRH agonists were similar to controls. CONCLUSIONS: PF leptin levels are elevated in women with endometriosis, but inversely correlated with extent of disease. These findings suggest a potential role for leptin in the pathogenesis of peritoneal endometriosis.     

Increased expression of matrix metalloproteinase-9 in the eutopic endometrial tissue of women with endometriosis

BACKGROUND: Endometriosis is a disease where endometrial tissue implants in ectopic locations. Remodelling of the extracellular matrix (ECM) is a prerequisite for the implantation of this tissue to be possible. METHODS: In this study, we detected immunoreactive matrix metalloproteinase-9 (MMP-9) throughout endometrial tissue and identified von Willebrand factor (vWF)-positive endothelial cells, CD45-positive leukocytes, CD3-positive T lymphocytes and CD68-positive macrophages as cells expressing MMP-9 in the stroma. RESULTS: We found an increased expression of MMP-9 in the uterine endometrial tissue of women with endometriosis, as assessed by zymography and enzyme-linked immunosorbent assay (ELISA) (P < 0.05). However, RT-PCR did not show a statistically significant increase in MMP-9 mRNA expression in these tissues (P = 0.14). There was no significant difference between women with and without endometriosis in the expression of tissue inhibitor of MMPs (TIMP)-1, a known natural inhibitor of the pro- and active forms of MMP-9, whether tested by ELISA or by RT-PCR (P = 0.46 and 0.37, respectively). Interestingly, the ratio of MMP-9/TIMP-1 expression was significantly higher in women with endometriosis than in normal women both at the protein and the mRNA levels (P < 0.05). CONCLUSION: These findings make plausible the involvement of MMP-9/TIMP-1 imbalance in the invasiveness of the endometrial tissue of patients with endometriosis and the ectopic development of the disease.     

Quantitative differences in matrix metalloproteinase (MMP)-2, but not in MMP-9, tissue inhibitor of metalloproteinase (TIMP)-1 or TIMP-2, in seminal plasma of normozoospermic and azoospermic patients

BACKGROUND: Matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs), have been detected in reproductive tissues and seminal plasma. The purpose of this study was to quantify MMP-2, MMP-9, TIMP-1 and TIMP-2 in human seminal plasma and to evaluate their association with sperm. METHODS: Seminal plasma was analysed using ELISA assays for all four analytes in 12 normozoospermic and 12 azoospermic patients and then for MMP-2 only in another 114 men with azoospermia (n = 16), after vasectomy (n = 20) and with sperm counts within the following ranges: 0.3-19 x 10(6)/ml (n = 20), 20-23 x 10(6)/ml (n = 11), 49-57 x 10(6)/ml (n = 12), 96-110 x 10(6)/ml (n = 12), 139-161 x 10(6)/ml (n = 12) and 215-346 x 10(6)/ml (n = 11). Additional zymographic analyses using SDS-PAGE were performed. RESULTS: All investigated MMPs and TIMPs were detected. MMP-9, TIMP-1 and TIMP-2 were not significantly different in normozoospermia and azoospermia. Only the MMP-2 concentration was significantly decreased in azoospermic compared with normozoospermic patients (mean +/- SD: 650.6 +/- 288.9 versus 1677 +/- 910.4 ng/ml respectively; P = 0.0002) and significantly correlated with the number of sperm (r = 0.54; P < 0.0001). CONCLUSION: MMP-2 in seminal plasma was strongly correlated to the sperm count in a linear fashion. Its origin and potential function remain to be elucidated.     

Paracrine changes in the peritoneal environment of women with endometriosis

During the past decade, macrophage-derived substances such as prostanoids, cytokines, growth factors and angiogenic factors have been detected in the peritoneal fluid of women with endometriosis. In particular, growth-promoting and angiogenic factors are considered to be substantially involved in the pathogenesis of endometriosis. In this study, vascular endothelial growth factor (VEGF), transforming growth factor beta (TGF-beta) and intercellular adhesion molecule 1 (ICAM-1), substances recently detected in the peritoneal fluid of women with endometriosis, were assessed with regard to their concentrations in different stages of endometriosis and changes of the peritoneal paracrine activity after medical treatment with a gonadotrophin releasing hormone agonist (GnRHa). Peritoneal fluid was obtained from patients with endometriosis during laparoscopy before and after a 4-month treatment with a GnRHa. VEGF, TGF-beta and ICAM-1 could be detected in all women presenting with various stages of active endometriosis. After GnRHa therapy, all patients showed significant decreases in mean concentrations of VEGF (194+/-77 pg/ml), TGF-beta (902+/-273 pg/ml) and ICAM-1 (157+/-52 ng/ml). Patients with stage III and IV endometriosis (according to the rAFS score) had much higher concentrations of VEGF and TGF-beta before treatment compared with those patients with mild endometriosis (rAFS stages I and II). The most striking decrease in concentration was for TGF-beta, from 902 pg/ml before to 273 pg/ml after therapy. These results indicate an important role for paracrine activity in the establishment and maintenance of endometriosis. Indeed, treatment with a GnRHa may reduce paracrine activity in the peritoneal cavity via hypo-oestrogenism and provide proof of successful therapy.     

Peritoneal fluid leptin is associated with chronic pelvic pain but not infertility in endometriosis patients

BACKGROUND: Leptin influences the proinflammatory immune responses and has angiogenic activity in vitro and in vivo. The objective of this study was to evaluate the peritoneal fluid levels of leptin in patients with endometriosis and idiopathic infertility and compare them with a control group of tubal ligation/reanastomosis patients. METHODS: In this observational, prospective controlled study, peritoneal fluid from 108 women was obtained while they underwent laparoscopy for pelvic pain, infertility, tubal ligation or sterilization reversal. We measured the concentration of leptin in the peritoneal fluid and compared the levels among women who were divided into groups according to their post-surgical diagnosis. Sixty patients were diagnosed with endometriosis, 10 with idiopathic infertility and 38 had undergone tubal ligation or reanastomosis (control group). RESULTS: Peritoneal fluid leptin was significantly higher in endometriosis 14.62+/-9.79 (mean+/-SD) ng/ml compared to idiopathic infertility [0.92+/-1.57 ng/ml (P=0.0007)] and to controls [0.78+/-1.94 ng/ml (P<0.0001)]. Leptin levels were positively correlated with the stage of endometriosis (r=0.45; P=0.03), and with pelvic pain in endometriosis patients (r=0.49; P=0.001). Peritoneal fluid leptin levels in patients with idiopathic infertility were comparable to controls. CONCLUSIONS: Higher levels of leptin were observed in peritoneal fluid of patients with endometriosis compared to those without the disease. These data suggest that the proinflammatory and neoangiogenic action of leptin may contribute to the pathogenesis of endometriosis. Moreover, leptin may play a role in endometriosis-associated pain.     

Children with stable asthma have reduced airway matrix metalloproteinase-9 and matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 ratio

BACKGROUND: Childhood asthma is characterized by inflammation of the airways. Structural changes of the airway wall may also be seen in some children early in the course of the disease. Matrix metalloproteinases (MMPs) are key mediators in the metabolism of the extracellular matrix (ECM). OBJECTIVE: To investigate the balance of MMP-8, MMP-9 and tissue inhibitor of metalloproteinases (TIMP)-1 in the airways of children with asthma. METHODS: One hundred and twenty-four children undergoing elective surgical procedures also underwent non-bronchoscopic bronchoalveolar lavage (BAL). MMP-8, MMP-9 and TIMP-1 were measured by ELISA. RESULTS: There was a significant reduction in MMP-9 in atopic asthmatic children (n=31) compared with normal children (n=30) [median difference: 0.57 ng/mL (95% confidence interval: 0.18-1.1 ng/mL)]. The ratio of MMP-9 to TIMP-1 was also reduced in asthmatic children. Levels of all three proteins were significantly correlated to each other and to the relative proportions of particular inflammatory cells in BAL fluid (BALF). Both MMP-8 and MMP-9 were moderately strongly correlated to the percentage neutrophil count (r=0.40 and 0.47, respectively, P<0.001). CONCLUSIONS: An imbalance of MMPs and their inhibitors occurs in children with well-controlled asthma, which may indicate early derangement of the metabolism of the ECM.     

Eutopic endometrium and peritoneal,ovarian and bowel endometriotic tissues express a different profile of matrix metalloproteinases-2, -3 and -11, and of tissue inhibitor metalloproteinases-1 and -2

Endometriosis is subsequent to the ability of endometrial glands to invade normal tissues. Matrix metalloproteinases (MMPs)—enzymes that mediate normal tissue turnover, including endometrial breakdown during menstruation—appear to be involved in this invasive process. Here, we examined the immunohistochemical expression of MMP-2, MMP-3, MMP-11, tissue inhibitor metalloproteinase (TIMP)-1 and TIMP-2 in endometrium from women with (n=9) or without endometriosis (n=18) in comparison with peritoneal (n=20), ovarian (n=20) and colorectal endometriosis (n=20). Women with endometriosis showed decreased endometrial MMP-2 expression compared with women without endometriosis (mean±SD positive cells: 24.3±28.3% and 69.3±12.1%), together with loss of MMP-3 expression (0 versus 17.5%±20.2). MMP-11, TIMP-1 and TIMP-2 expression was similar in the two groups. Endometrial MMP-2, -3 and -11 expression and TIMP-1 and -2 expression were similar in women with endometriosis and in those with peritoneal endometriosis. MMP-2, -3 and -11 expression was higher in colorectal endometriosis than in ovarian and peritoneal endometriosis. TIMP-2 expression was lower in colorectal endometriosis (P=0.0002) and ovarian endometriotic cysts (P=0.003) than in peritoneal endometriosis. TIMP-1 expression did not vary according to the location of endometriotic lesions. These results suggest that MMP-2 and -3 and TIMP-2 may be involved in the pathogenesis of endometriosis. Interestingly, MMP-2 and -3 overexpression was related to the infiltrative nature of endometriotic lesions, with possible sequential expression from peritoneal to colorectal endometriosis.     

Effects of low-density lipoprotein apheresis on plasma matrix metalloproteinase-9 and serum tissue inhibitor of metalloproteinase-1 levels in diabetic hemodialysis patients with arteriosclerosis obliterans

Low density lipoprotein (LDL) apheresis provides both structural and physiologic improvement to the vascular wall. The purpose of this study was to determine whether LDL pheresis alters levels of plasma matrix metalloproteinase-9 (MMP-9) and serum tissue inhibitor of matrix metalloproteinase-1 (TIMP-1). MMP-9 and TIMP-1 were measured in 30 healthy control subjects (Group A), 20 type 2 diabetic hemodialysis patients without obvious arteriosclerosis obliterans (ASO) (Group B), and 20 type 2 diabetic hemodialysis patients with ASO (Group C). Hemodialysis patients were dialyzed three times weekly with a bicarbonate dialysate. Twelve Group C patients underwent LDL apheresis once weekly for 10 weeks, and changes in plasma MMP-9 and serum TIMP-1 levels because of LDL apheresis were measured. LDL apheresis resulted in a significant decrease in total cholesterol and LDL cholesterol levels (p < 0.01). In addition, LDL apheresis improved clinical symptoms (including cold lower extremity, intermittent claudication, and leg pain) and diminished the size of ulcer/necrosis in all patients. Plasma MMP-9 levels were significantly higher in Group C (76.5 +/- 14.6 ng/ml) than in Group A (31.2 +/- 8.4 ng/ml, p < 0.001) or Group B (58.5 +/- 10.8 ng/ml, p < 0.05). Serum TIMP-1 levels were significantly higher in Group C (360.5 +/- 116.5 ng/ml) than in Group A (142.5 +/- 82.5 ng/ml, p < 0.001) or Group B (254.6 +/- 92.6 ng/ml, p < 0.05). Plasma MMP-9 and serum TIMP-1 levels decreased significantly after LDL apheresis (p < 0.05). However, these levels showed little change in the remaining eight Group C patients who did not undergo LDL apheresis. The data suggested that MMP-9 and TIMP-1 are associated with ASO and that LDL apheresis is effective in reducing plasma MMP-9 and TIMP-1 levels in type 2 diabetic hemodialysis patients with ASO.     

The peritoneal fluid concentration of leptin is increased in women with peritoneal but not ovarian endometriosis

This study was designed to measure leptin concentrations in the peritoneal fluid (PF) of women with different aspects of pelvic endometriosis. Among 36 consecutive women undergoing laparoscopy, nine were diagnosed as having minimal-mild endometriosis (stage I-II). Among nine other subjects with advanced stage (III-IV) disease, six showed one or more ovarian endometriotic cysts as the only operative finding. The remaining 18 unaffected women constituted the control group. Patients with endometriosis had significantly higher PF leptin concentrations (32.6 +/- 16.2 versus 17.1 +/- 6.6 ng/ml, P = 0.002); this difference remained significant when corrected for body mass index (BMI) (PF leptin/BMI ratio 1.41 +/- 0.67 versus 0.76 +/- 0.28, P = 0.001). Furthermore, the PF leptin/BMI ratio was significantly higher in women with peritoneal implants than in those in whom no implant was found at laparoscopy (1.6 +/- 0.7 versus 0.83 +/- 0.33, P = 0.007). Conversely, patients with one or more ovarian endometriomata as the only finding, had a PF leptin/BMI ratio comparable with that in women where no cyst was found (1.05 +/- 0.4 versus 1.1 +/- 0.65). In women with stage I-II endometriosis, a higher mean PF leptin/BMI ratio was found compared with those affected by stage III-IV (1.78 +/- 0.68 versus 1.05 +/- 0.43, P = 0.01). These results show that during endometriosis the presence of peritoneal disease, and not of ovarian endometriotic cysts, influences leptin concentrations in PF. The data suggest that leptin may play a role in the development of peritoneal endometriosis, and that different biochemical phenomena might be involved in the pathogenesis of the ovarian form of the disease.     

Expression of several components of the plasminogen activator and matrix metalloproteinase systems in endometriosis

BACKGROUND: Endometriosis is considered a benign disease that has the ability to invade normal tissue. As in neoplastic growth, local extracellular proteolysis may take place. The aim of this study is to analyse several components of the plasminogen activator (PA) pathway and the matrix metalloproteinase (MMP) system in endometriotic tissue, endometrium and peritoneal fluid from women with and without endometriosis (controls). METHODS AND RESULTS: Thirty-nine women with endometriosis and 35 controls were studied. In eutopic endometrium of women with endometriosis, the antigenic levels of urokinase-type PA (uPA) and MMP-3 were elevated when compared with endometrium from controls. Ovarian endometriotic tissues had higher antigenic levels of PA inhibitor type 1 (PAI-1) and tissue inhibitor of metalloproteinases type 1 (TIMP-1) than endometrium. The peritoneal fluid from women with endometriosis showed a significant increase in uPA levels compared with controls. CONCLUSIONS: The increase in antigenic levels of uPA and MMP-3 in endometrium of women with endometriosis might contribute to the invasive potential of endometrial cells. Once the ovarian endometriotic cyst is developed, an increase in PAI-1 and TIMP-1 is detected and significant proteolytic activity is no longer observed. This increase in inhibitors and decrease in proteolytic activity could explain the frequent clinical finding of isolated endometriotic cyst without invasion of the surrounding ovarian tissue.     

Increased levels of interleukin-15 in the peritoneal fluid of women with endometriosis: inverse correlation with stage and depth of invasion

BACKGROUND: Interleukin (IL)-15 is a novel cytokine with immunoregulatory and angiogenic properties. We compared IL-15 levels in the peritoneal fluid (PF) of women with and without endometriosis. METHODS: PF samples were obtained from 55 women with endometriosis (23 with superficial peritoneal implants, 19 with deep endometriotic implants and 13 with ovarian endometriomas). Eighteen women with normal pelvic anatomy undergoing tubal sterilization served as controls. RESULTS: PF IL-15 concentrations were increased in women with endometriosis (2.7 +/- 0.5 pg/ml) versus controls (2.1 +/- 0.3 pg/ml; P < 0.001). However, IL-15 levels were higher in women with superficial peritoneal implants (2.9 +/- 0.5 pg/ml) than women with deep endometriotic implants (2.6 +/- 0.4 pg/ml; P = 0.01) or ovarian endometriomas (2.2 +/- 0.4 pg/ml; P < 0.001). IL-15 was also higher in women with deep implants than in those with endometriomas (P < 0.05). PF IL-15 correlated inversely with both depth of invasion (r = -0.52) and the stage of endometriosis (r = -0.42). PF IL-15 levels demonstrated little variation during the menstrual cycle, and did not discriminate between women with infertility or pelvic pain. CONCLUSION: PF IL-15 levels are increased in women with endometriosis. However, IL-15 levels are inversely correlated with the depth of invasion and disease stage, suggesting a possible role for this cytokine in the early pathogenesis of endometriosis.     

Dynamic Changes of Matrix Metalloproteinase-9 in Patients with Klebsiella pneumoniae Meningitis

To quantitate cerebrospinal fluid (CSF) concentrations of matrix metalloproteinase 9 (MMP-9) in adult patients with Klebsiella pneumoniae meningitis and to correlate levels of MMP-9 with parameters of intrathecal inflammation and analyze the kinetic changes of MMP-9. In a prospective cohort study, levels of MMP-9 and tissue inhibitor of matrix metalloproteinase (TIMP-1) concentrations were measured in the CSF of six adult patients with meningitis and 11 controls. MMP-9 and TIMP-1 were detected in all of the six patients at presentation and follow up lumbar puncture. CSF levels of MMP-9 (6.71+/-7.29 ng/ml) and TIMP-1(454.3+/-242.9 ng/ml) were higher in patients than in the control group (0.07+/-0.11 ng/ml and 27.14+/-39.34 ng/ml, respectively). Levels of MMP-9 correlated with CSF concentrations of protein, cell count and lactate. Repeated lumbar punctures showed that levels of MMP-9 decrease during clinical recovery, although the levels of MMP-9 in the CSF are variable because of the small number of cases. The relative change in gelatin zymography is comparable to the changes of MMP-9 levels found in ELISA. MMP-9 levels in CSF may be a useful tool in follow-up in patients with K. pneumoniae meningitis.     

Evidence for an increased release of proteolytic activity by the eutopic endometrial tissue in women with endometriosis and for involvement of matrix metalloproteinase-9

BACKGROUND: For the implantation of endometrium in ectopic locations, remodelling of the extracellular matrix (ECM) is necessary. Many studies have shown an increased expression of various proteases in the ectopic endometrium of women with endometriosis. Few, however, have addressed possible changes in protease expression in the eutopic endometrium. METHODS AND RESULTS: Herein, we reveal an increased release of proteolytic activity by the eutopic endometrium of women with endometriosis compared with normal women (P < 0.01). Using zymography and western blotting, we identified matrix metalloproteinase (MMP)-2 and MMP-9 in the culture medium, and further found that MMP-9 secretion, as assessed by zymography and enzyme-linked immunosorbent assay (ELISA), was elevated in women with endometriosis compared with normal women (P < 0.05). No statistically significant difference in MMP-2 secretion between women with and without endometriosis was noted. However, a significant difference in the levels of the tissue inhibitor of metalloproteinases (TIMP)-1, a known MMP-9 inhibitor, was found (P < 0.05). CONCLUSION: The endometriosis-associated increase in proteolysis and imbalance between the secretion of MMP-9 and that of its natural inhibitor, TIMP-1, revealed in the culture medium of endometrial tissue may reflect in vivo the enhanced capacity of this tissue to break down the ECM in host tissues, thereby favouring its ectopic implantation and development.     

Hepatocyte growth factor concentrations are elevated in peritoneal fluid of women with endometriosis.

The concentrations of hepatocyte growth factor (HGF) in peritoneal fluid (PF) from women with endometriosis (n = 36) and without endometriosis (n = 40) were measured. All of the PF samples examined contained detectable concentrations of HGF. The HGF concentrations in PF from women with stage III/IV endometriosis (0.906 ng/ml, 0. 561-1.185; median, interquartile range) were significantly higher (P < 0.0001) than those from women without endometriosis (0.315 ng/ml, 0.251-0.472). The HGF concentrations from women with stage I/II endometriosis (0.417 ng/ml, 0.310-1.023) appeared to be intermediate. There were no apparent variations detected among the HGF concentrations in women in the follicular or luteal phases regardless of the presence of endometriosis. Interestingly, HGF concentrations in PF from women on gonadotrophin releasing hormone analogues, independent of the presence of endometriosis, were comparable with those from untreated women. Given the known mitogenic property of HGF in human endometrial cells, these results suggest that HGF might play a role in the progression of endometriosis.     

The effect of hormone therapy and raloxifene on serum matrix metalloproteinase-2 and -9 in postmenopausal women

OBJECTIVE: The aim of the study was to investigate the effect of continuous-combined hormone therapy and raloxifene on the total and active forms of serum matrix metalloproteinase (MMP) -2 and -9. DESIGN: The study was double-blinded, with a placebo run-in period of 28 to 50 days. Twenty-eight women received either 17beta-estradiol 2 mg + norethisterone acetate 1 mg (E2/NETA) or raloxifene HCL 60 mg for a period of 6 months. Total and active forms of MMP-2 and -9 were estimated at baseline and at month 6. RESULTS: Total MMP-2 increased significantly in both E2/NETA and raloxifene groups (raloxifene baseline: 278.1 +/- 18.1 ng/mL; 6 months: 303.1 +/- 29.9 ng/mL, P = 0.008) (E2/NETA baseline: 281.9 +/- 27.5 ng/mL; 6 months: 298.8 +/- 12.7 ng/mL, P = 0.025). Similarly, both treatments increased the active MMP-2 fraction, although only the raloxifene-associated increase acquired significance (raloxifene baseline: 24.9 +/- 8.6 ng/mL; 6 months: 31.6 +/- 15.3 ng/mL, P = 0.045) (E2/NETA baseline: 21.7 +/- 5.7 ng/mL; 6 months: 27.4 +/- 5.8 ng/mL, P = 0.128). Total as well as active fractions of MMP-9 were not significantly affected by either treatment. CONCLUSIONS: Both E2/NETA and raloxifene increased the total and active MMP-2 serum levels. MMP-9 was not significantly affected by either regimen. Larger, long-term clinical trials are needed to elucidate the effect of HT and raloxifene on MMPs and the possible clinical implications for cardiovascular health.     

Evidence of in vitro differential secretion of 72 and 92 kDa type IV collagenases after selective exposure to lipopolysaccharide in human fetal membranes

Premature rupture of chorioamniotic membranes complicated with intrauterine infection has been associated to degradation of extracellular matrix (ECM), which could explain local morphological changes. We used a culture system in which the chorioamniotic membranes form two independent chambers, allowing for the selective stimulation of either the amnion (AMN) and/or the choriodecidua (CHD) regions. Lipopolysaccharide (500 ng/ml) was added to the AMN and/or the CHD; secretions and gelatinolytic activity of matrix metalloproteinase (MMP)-2 and MMP-9 were measured in both compartments by enzyme-linked immunosorbent assay (ELISA) and zymography. Secretions of TIMP-1, TIMP-2 and TIMP-4 were measured by ELISA. Both metalloproteinases were immunolocalized in tissue sections. All stimulation modalities induced a similar proMMP-2 and proMMP-9 secretion pattern in the CHD with concentrations of 2.49 ng/ml and 90.91 pg/ml, respectively; the AMN showed no significant changes. The active forms of both enzymes did not change with any stimulation modality. TIMP-1, TIMP-2 and TIMP-4 secretions remained without significant changes (P = 0.41). ECM degradation and structural disarrangement were evident after stimulation. Secretion of proMMP-2 and proMMP-9 mainly in the CHD, presence of active forms associated to the tissue and minor changes in TIMPs secretion could favor ECM degradation and explain the weakening and thinning associated with the pathological rupture of chorioamniotic membranes.     

Role of IL-18 in pathogenesis of endometriosis

BACKGROUND: Endometriosis is a complex disease associated with a wide range of immune responses, including pain, adhesion, exudation of peritoneal fluid, elevation of cytokine levels and generation of autoantibodies. Interleukin (IL)-18 is a strong pleiotropic cytokine known to be involved in various immune diseases. The aim of this study is to elucidate the role of IL-18 in the pathogenesis of endometriosis. METHODS: IL-18 and IL-1beta concentrations were measured in the peritoneal fluid and sera of 39 endometriosis patients and 15 control women. Expression of IL-18 and IL-18 receptor alpha-chain (IL-18Ralpha) was analysed in endometriotic tissues immunohistochemically. The effects of IL-18 on cyclooxygenase (COX)-II gene expression were analysed in peritoneal fluid monocytes and endometriotic cells of endometriosis patients. RESULTS: IL-18 concentrations in the peritoneal fluid of endometriosis patients averaged 592.57 +/- 108.27 pg/ml, significantly higher than 260.50 +/- 55.88 pg/ml in non-endometriotic samples. IL-18 concentrations in the serum did not differ significantly between endometriosis and control patients. Similarly, no significant differences were observed in IL-1beta concentrations in either the peritoneal fluid or the serum. IL-18 and IL-18Ralpha were expressed in endometriotic tissues. IL-18Ralpha expression was also observed in cells infiltrating into the inflammatory area of the endometriosis patients. COX-II was induced in peritoneal fluid monocytes and in endometriotic cells in response to IL-18 stimulation. CONCLUSIONS: The elevation of IL-18 in the peritoneal fluid of endometriosis patients and the induction of COX-II in peritoneal monocytes by IL-18 suggest that IL-18 plays a pathogenic role in endometriosis.     

Possible implication of midkine in the development of endometriosis

BACKGROUND: The present study was conducted to assess whether midkine (MK), a multifunctional molecule known to stimulate tumor growth, may be involved in the development of endometriosis. METHODS: The mitogenic activity of MK on cultured endometriotic stromal cells was examined by measuring 5-bromo-2'-deoxyuridine (BrdU) incorporation. Concentrations of MK in the peritoneal fluid (PF) of women without or with endometriosis and those under GnRH agonist treatment were measured using a specific enzyme immunoassay. The expression of MK mRNA in peritoneal bone marrow-derived cells, peritoneum and endometriotic tissues was evaluated by RT-PCR. RESULTS: MK significantly increased BrdU incorporation into the DNA of cultured endometriotic stromal cells. The MK concentrations in the PF of the women with advanced endometriosis (stages II, III and IV) Median: 1.21 ng/ml; interquartile range 0.80-2.27 were significantly higher than those of the women without endometriosis and with stage I endometriosis (0.06 ng/ml, 0.67-1.26, P < 0.05). As for the menstrual phase, the MK concentration in PF in the inteal phase (1.32 ng/ml. 0.72-2.21) were significantly higher than those in the follicular phase (0.95 ng/ml, 0.68-1.24, P < 0.05). In addition, women with adnexal adhesions had higher concentrations of MK in PF than those without adhesions (P < 0.05). The MK concentrations of the women under GnRH agonist treatment were significantly lower than those of the other groups (P < 0.001). The expression of MK mRNA was detected in peritoneal bone marrow-derived cells, peritoneum and endometriotic tissues. CONCLUSIONS: The present findings suggest that MK may play roles, such as stimulation of endometriotic cell proliferation, in the development of endometriosis.     

Increased concentrations of cathepsin D in peritoneal fluid from women with endometriosis

To assess the release of the proteolytic enzyme cathepsin D in endometriosis, concentrations in peritoneal fluid and serum were measured by ELISA in 54 women with (n = 33) and without (n = 21) endometriosis. Surgery was scheduled in either the proliferative or secretory phase of the menstrual cycle. The concentrations of cathepsin D in the peritoneal fluid were markedly elevated in the endometriosis patients (median 58 ng/ml, interquartile range 0-166 ng/ml) as compared to the controls (5 ng/ml, 0-86 ng/ml), especially in women with late stage disease (n = 19, stages III/IV) and in those not undergoing gonadotrophin-releasing hormone (GnRH) agonist therapy (n = 15). No significant difference was determined in cathepsin D concentrations of the serum from women with and without endometriosis. We conclude that cathepsin D is an important factor that may contribute to the pathogenesis of endometriosis, possibly by promoting digestion of extracellular matrix proteins. These results have implications for the therapeutic efficacy of GnRH agonists.     

Elevated levels of MMP-9 and TIMP-1 in the cerebrospinal fluid of children with echovirus type 30 and mumps meningitis

Matrix metalloproteinases are involved in leucocyte invasion into the central nervous system (CNS) during meningitis. The aim of the study was to determine whether there are differences in the expression patterns of matrix metalloproteinase-9 (MMP-9) and the tissue inhibitor of metalloproteinase-1 (TIMP-1) in the cerebrospinal fluid (CSF) of patients with meningitis caused by one of two known distinct viral agents. Concentrations were measured by using an enzyme-linked immunosorbent assay (ELISA) in 16 children with mumps meningitis, in 25 children with echovirus type 30 meningitis and in a control group of 23 children without any CNS infection. Increased levels of MMP-9 were found in children with mumps (median 0.48 ng/ml; P  < 0.001) and enteroviral meningitis (median 2.76 ng/ml; P  < 0.001) compared with that in controls (median: 0.01 ng/ml). Concentrations of TIMP-1 greatly exceeded concentrations of MMP-9 and were elevated in children with mumps (median: 56 ng/ml) and echovirus type 30 meningitis (median: 55 ng/ml) compared to controls (median: 17 ng/ml). No significant differences in MMP-9 or TIMP-1 levels were detected between the two meningitis groups. The MMP-9/TIMP-1 ratio was greater in children with echovirus type 30 than in those with mumps meningitis. There was no correlation between MMP-9 levels and total CSF cell count. MMP-9 correlated with CSF absolute neutrophil count in children with echovirus type 30 meningitis ( r  = 0.431; P  < 0.05). The concentration of MMP-9 is higher in children with viral meningitis, possibly because of infiltrating polymorphonuclear cells present in the initial phase of the disease.