Evaluation of N-acetilglucosaminidase and myeloperoxidase activity in patients with endometriosis-related infertility undergoing intracytoplasmic sperm injection

A high concentration of neutrophil extracellular traps is observed in humans and mice suffering from endometriosis

We wished to ascertain if there is an association between neutrophil extracellular traps and endometriosis (EMS). We collected the lesional tissues and normal endometrium of 30 patients suffering from endometriosis. Samples were also taken from healthy controls. Blood from the peripheral circulation was collected to isolate serum and neutrophils. A mouse model of endometriosis was also created. Expression of citrullinated histone and the myeloperoxidase level in tissue were measured by immunofluorescence staining and western blotting. The myeloperoxidase level in peripheral blood serum was measured by enzyme-linked immunosorbent assay. Staining (Trypan Blue) and flow cytometry were used to measure the apoptosis of neutrophils in peripheral blood. BALB/C mice were modeled by allotransplantation, and the experimental parameters noted above quantified. The myeloperoxidase content in the peripheral blood of patients with endometriosis was increased compared with that in healthy controls. Flow cytometry showed that the percent apoptosis of neutrophils in patients with endometriosis was lower than that in healthy controls. Expression of citrullinated histone was higher in the endometriosis group in humans and mice compared with respective controls according to immunofluorescence staining and western blotting. Our data suggest that a high concentration of neutrophil extracellular traps was observed in humans and mice suffering from endometriosis.

The Pathological Role of miRNAs in Endometriosis

Association studies investigating miRNA in relation to diseases have consistently shown significant alterations in miRNA expression, particularly within inflammatory pathways, where they regulate inflammatory cytokines, transcription factors (such as NF-κB, STAT3, HIF1α), and inflammatory proteins (including COX-2 and iNOS). Given that endometriosis (EMS) is characterized as an inflammatory disease, albeit one influenced by estrogen levels, it is natural to speculate about the connection between EMS and miRNA. Recent research has indeed confirmed alterations in the expression levels of numerous microRNAs (miRNAs) in both endometriotic lesions and the eutopic endometrium of women with EMS, when compared to healthy controls. The undeniable association of miRNAs with EMS hints at the emergence of a new era in the study of miRNA in the context of EMS. This article reviews the advancements made in understanding the pathological role of miRNA in EMS and its association with EMS-associated infertility. These findings contribute to the ongoing pursuit of developing miRNA-based therapeutics and diagnostic markers for EMS.

Involvement of Anti-Inflammatory and Stress Oxidative Markers in the Antidepressant-like Activity of Aloysia citriodora and Verbascoside on Mice with Bacterial Lipopolysaccharide- (LPS-) Induced Depression

Aloysia citriodora Palau is popularly used to treat nervous disorders. Experimental evidence has indicated that verbascoside (VBS) isolated from A. citriodora has pharmacological potential. In this study, we evaluated the antidepressant-like effects of a hydroalcoholic extract of A. citriodora (HEAc) and VBS against lipopolysaccharide- (LPS-) induced depressive-like behavior in mice. In the pretreatment protocol (performed to evaluate the preventive potential), mice were pretreated with HEAc (3, 30, or 300 mg/kg) or VBS (30 mg/kg) before the administration of LPS. In the posttreatment protocol (performed to evaluate the therapeutic potential), mice were initially administered LPS and were subsequently given HEAc (3, 30, or 300 mg/kg) or VBS (30 mg/kg). In both treatments, the mice were submitted to an open-field test and tail suspension test (TST) at 6 and 24 h after LPS administration. The posttreatment evaluation revealed that HEAc (30 or 300 mg/kg) and VBS produced an antidepressant-like effect, as indicated by a reduction in the time spent with no movement in the TST. Moreover, HEAc (30 or 300 mg/kg) was found to reduce interleukin-6 (IL-6) levels and N-acetyl-glycosaminidase activity in the hippocampus, increase glutathione (GSH) levels in the hippocampus and cortex, and enhance IL-10 in the cortex and, at a dose of 300 mg/kg, reduced myeloperoxidase activity in the cortex. Contrastingly, no comparable effects were detected in mice subjected to the pretreatment protocol. Administration of VBS similarly reduced the levels of IL-6 in the hippocampus and increased GSH levels in the cortex. Our observations indicate that both HEAc and VBS show promising antidepressant-like potential, which could be attributed to their beneficial effects in reducing neuroinflammatory processes and antioxidant effects in the central nervous system.

Ethiopathogenic mechanisms of endometriosis-related infertility

Endometriosis is a highly prevalent disease among women of reproductive age and is frequently associated to infertility. However, the mechanisms underlying endometriosis-related infertility are still not completely known. Several studies have been conducted in order to elucidate this question. Besides anatomical changes that may impair gametes and embryo transport along the tubes; a smaller ovarian reserve due to advanced endometriosis and endometriomas; and a dysregulated hypothalamic-pituitary-ovarian axis, there are pieces of evidence suggesting that the peritoneal ectopic endometrial foci may induce a local inflammatory response, with the recruitment of macrophages, cytokine release, and reactive oxygen species generation, leading to a pro-oxidant peritoneal microenvironment. These alterations may be systemically reflected and also affect the follicular microenvironment. A harmful follicular fluid may disrupt cumulus cells functions and, consequently, compromise oocyte competence. There is also evidence suggesting that the peritoneal fluid of women with endometriosis may alter sperm function. Reduced endometrial receptivity is also pointed as a possible mechanism involved in endometriosis-related infertility, which needs further investigation.

The Impact of Myeloperoxidase and Activated Macrophages on Metaphase II Mouse Oocyte Quality

Myeloperoxidase (MPO), an abundant heme-containing enzyme present in neutrophils, monocytes, and macrophages, is produced in high levels during inflammation, and associated with poor reproductive outcomes. MPO is known to generate hypochlorous acid (HOCl), a damaging reactive oxygen species (ROS) utilizing hydrogen peroxide (H₂O₂) and chloride (Cl^-). Here we investigate the effect of activated immune cells and MPO on oocyte quality. Mouse metaphase II oocytes were divided into the following groups: 1) Incubation with a catalytic amount of MPO (40 nM) for different incubation periods in the presence of 100 mM Cl^- with and without H₂O₂ and with and without melatonin (100 μM), at 37°C (n = 648/648 total number of oocytes in each group for oocytes with and without cumulus cells); 2) Co-cultured with activated mouse peritoneal macrophage and neutrophils cells (1.0 x 10⁶ cells/ml) in the absence and presence of melatonin (200 μM), an MPO inhibitor/ROS scavenger, for different incubation periods in HTF media, at 37°C (n = 200/200); 3) Untreated oocytes incubated for 4 hrs as controls (n = 73/64). Oocytes were then fixed, stained and scored based on the microtubule morphology and chromosomal alignment. All treatments were found to negatively affect oocyte quality in a time dependent fashion as compared to controls. In all cases the presence of cumulus cells offered no protection; however significant protection was offered by melatonin. Similar results were obtained with oocytes treated with neutrophils. This work provides a direct link between MPO and decreased oocyte quality. Therefore, strategies to decrease MPO mediated inflammation may influence reproductive outcomes.

Evaluation of oxidative stress markers and intra-extracellular antioxidant activities in patients with endometriosis

OBJECTIVE

The aim of the study is to evaluate alterations in intracellular and extracellular antioxidant enzymes activities and serum oxidative stress markers in patients with endometriosis.

STUDY DESIGN

The current prospective study consisted of 31 female patients with endometriosis and 27 healthy controls. Serum total thiol, native thiol, disulphide, catalase, myeloperoxidase, and ceruloplasmin concentrations were measured. Laboratory and clinical data of all participants were recorded to compare the differences between the study and the control groups.

RESULTS

Serum native thiol and total thiol levels in the study group were significantly lower than those in the control group [(p=0.009, p=0.03, respectively)]. Serum catalase levels are significantly higher in patients with endometriosis comparing to the control group (p=0.009).

CONCLUSIONS

The finding that significant differences in serum total thiol, native thiol, and catalase levels observed in endometriotic patients supports that oxidative stress carries weigh in the pathophysiological aspects of endometriosis. Also significantly low levels of extracellular antioxidants and significantly high levels of intracellular antioxidants in endometriotic patients may arise from differences of free radicals in endometriosis and the activity levels of endometriosis. These non-invasive serum markers might give us an opportunity to monitor the disease's progress during the treatment.

The Defensive Role of Cumulus Cells Against Reactive Oxygen Species Insult in Metaphase II Mouse Oocytes

We investigated the ability of reactive oxygen species (ROS), such as hydrogen peroxide (H(2)O(2)), hydroxyl radical ((·)OH), and hypochlorous acid (HOCl), to overcome the defensive capacity of cumulus cells and elucidate the mechanism through which ROS differentially deteriorate oocyte quality. Metaphase II mouse oocytes with (n = 1634) and without cumulus cells (n = 1633) were treated with increasing concentration of ROS, and the deterioration in oocyte quality was assessed by the changes in the microtubule morphology and chromosomal alignment. Oocyte and cumulus cell viability and cumulus cell number were assessed by indirect immunofluorescence, staining of gap junction protein, and trypan blue staining. The treated oocytes showed decreased quality as a function of increasing concentrations of ROS when compared to controls. Cumulus cells show protection against H(2)O(2) and (·)OH insult at lower concentrations, but this protection was lost at higher concentrations (>50 μmol/L). At higher H(2)O(2) concentrations, treatment dramatically influenced the cumulus cell number and viability with resulting reduction in the antioxidant capacity making the oocyte more susceptible to oxidative damage. However, cumulus cells offered no significant protection against HOCl at any concentration used. In all circumstances in which cumulus cells did not offer protection to the oocyte, both cumulus cell number and viability were decreased. Therefore, the deterioration in oocyte quality may be caused by one or more of the following: a decrease in the antioxidant machinery by the loss of cumulus cells, the lack of scavengers for specific ROS, and/or the ability of the ROS to overcome these defenses.

Impact of endometriosis and its staging on assisted reproduction outcome: systematic review and meta-analysis

OBJECTIVE

To evaluate whether the presence or severity of endometriosis affects the outcome of assisted reproductive techniques (ART).

METHODS

In this systematic review, all studies comparing the outcome of ART in women with and those without endometriosis, or at different stages of the disease, were considered eligible. We used either risk ratio (RR) or mean difference (MD) and their 95%CIs for comparisons. The primary outcome was live birth; the secondary outcome was clinical pregnancy. Miscarriage and the number of oocytes retrieved were examined as additional outcomes.

RESULTS

We included 92 studies in the review and 78 in the meta-analysis: 20,167 women with endometriosis were compared with 121,931 women without endometriosis, and 1703 women with Stage-III/IV endometriosis were compared with 2227 women with Stage-I/II endometriosis. The following results were observed for the comparison of women with endometriosis vs women without endometriosis: live birth, RR = 0.99 (95%CI, 0.92-1.06); clinical pregnancy, RR = 0.95 (95%CI, 0.89-1.02); miscarriage, RR = 1.31 (95%CI, 1.07-1.59); number of oocytes retrieved, MD = -1.56 (95%CI, -2.05 to -1.08). The following results were observed for the comparison of women with Stage-III/IV vs Stage-I/II endometriosis: live birth, RR = 0.94 (95%CI, 0.80-1.11); clinical pregnancy, RR = 0.90 (95%CI, 0.82-1.00); miscarriage, RR = 0.99 (95%CI, 0.73-1.36); number of oocytes retrieved, MD = -1.03 (95%CI, -1.67 to -0.39).

CONCLUSIONS

Women with endometriosis undergoing ART have practically the same chance of achieving clinical pregnancy and live birth as do women with other causes of infertility. No relevant difference was observed in the chance of achieving clinical pregnancy and live birth following ART when comparing Stage-III/IV with Stage-I/II endometriosis. The quality of the evidence for the additional examined outcomes was very low, not allowing meaningful conclusions to be drawn.

Identification of local angiogenic and inflammatory markers in the menstrual blood of women with endometriosis

The aim of this study was to evaluate the presence of myeloperoxidase (MPO), N-acetyl-β-D-glucosaminidase (NAG), tumor necrosis factor alpha (TNF-α) and vascular endothelial growth factor (VEGF) in peripheral and menstrual blood in women with (n=10) and without (n=7) endometriosis. NAG and MPO activities were evaluated by enzymatic methods, whereas TNF-α and VEGF by immunoassay. No significant differences were found for these markers, neither in menstrual nor in peripheral blood between groups. Menstrual blood NAG (P=0.039) and MPO (P=0.0117) activities in the endometriosis group were significantly higher than in peripheral blood. NAG and MPO presented positive linear correlation in peripheral (P=0.07; r=0.641) and menstrual blood (P=0.01; r=0.603). These findings point to the existence of an increased local inflammatory activity in women with endometriosis.

N-acetylglucosaminidase, myeloperoxidase and vascular endothelial growth factor serum levels in breast cancer patients

Inflammatory cells surround breast carcinomas and may act promoting tumor development or stimulating anti-tumor immunity. N-acetylglucosaminidase (NAG) has been employed to detect macrophage accumulation/activation. Myeloperoxidase (MPO) is considered a marker for neutrophils activity/accumulation. Vascular Endothelial Growth Factor (VEGF) is as strong pro-angiogenic cytokine. The aim of this study was to measure the systemic inflammatory response by measuring serum levels of NAG, MPO and VEGF in women diagnosed with breast cancer and associate this response to the peritumoral inflammatory infiltrate and to prognostic factors. Serum samples obtained from women with no evidence of disease (n=31) and with breast cancer (n=68) were analyzed for the activities of NAG, MPO and VEGF by enzymatic assay. Serum levels of NAG and VEGF were higher in healthy volunteers (P<0.0001) and serum levels of MPO were higher in patients with breast cancer (P=0.002). Serum levels of NAG were positively correlated to serum levels of MPO and VEGF (P<0.0001 and P=0.0012, respectively) and MPO and VEGF serum levels had also a positive correlation (P=0.0018). The inflammatory infiltrate was not associated to serum levels of the inflammatory markers, and higher levels of MPO were associated to lymphovascular invasion negativity (P=0.0175).