Growth-associated protein 43–positive sensory nerve fibers accompanied by immature vessels are located in or near peritoneal endometriotic lesions

Location-dependent value of pelvic MRI in the preoperative diagnosis of endometriosis

OBJECTIVES

To investigate the value of magnetic resonance imaging (MRI) in the preoperative diagnosis of specific anatomical locations of endometriosis.

STUDY DESIGN

Between July 2008 and April 2011, 152 women (mean age 33.5 ± 6.1 years) with clinical and sonographic suspicion of endometriosis underwent pelvic MRI using T2 and unenhanced T1 sequences with and without fat saturation. Two radiologists interpreted the following regions by consensus according to a standardized protocol: ovaries, vagina, pouch of Douglas, rectosigmoid colon, uterosacral ligament (USL), bladder, peritoneum, and other pelvic regions. The results of MRI were retrospectively correlated with the laparoscopic and histopathologic findings. The main outcome parameters, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, positive likelihood ratio (LR+) and the negative likelihood ratio (LR-), were determined.

RESULTS

Sensitivity, specificity, PPV, NPV, accuracy, positive and the negative likelihood ratio were 87.6%, 84.6%, 94.3%, 70.2%, 86.8%, 5.69 and 0.15 for the pouch of Douglas (vagina: 81.4%, 81.7%, 79.2%, 83.8%, 81.6%, 4.45, 0.23; rectosigmoid colon: 80.2%, 77.5%, 80.2%, 77.5%, 78.9%, 3.56, 0.25; USL: 77.5%, 68.2%, 77.5%, 68.2%, 73.7%, 2.44, 0.33; ovaries: 86.3%, 73.6%, 78.4%, 82.8%, 80.3%, 3.27, 0.19; urinary bladder: 81.0%, 94.7%, 70.8%, 96.9%, 92.8%, 15.15, 0.20; peritoneum: 35.3%, 88.1%, 60.0%, 73.0%, 70.4%, 2.97, 0.73). All endometriotic implants at other localization were detected (abdominal wall in 4, groin in one patient).

CONCLUSIONS

The value of MRI in preoperative diagnosis of endometriosis is dependent on the location of endometriosis. The highest accuracy was found in bladder endometriosis and the lowest in peritoneal endometriosis.

The effects of target skeletal muscle cells on dorsal root ganglion neuronal outgrowth and migration in vitro

Targets of neuronal innervations play a vital role in regulating the survival and differentiation of innervating neurotrophin-responsive neurons. During development, neurons extend axons to their targets, and then their survival become dependent on the trophic substances secreted by their target cells. Sensory endings were present on myoblasts, myotubes, and myofibers in all intrafusal bundles regardless of age. The interdependence of sensory neurons and skeletal muscle (SKM) cells during both embryonic development and the maintenance of the mature functional state has not been fully understood. In the present study, neuromuscular cocultures of organotypic dorsal root ganglion (DRG) explants and dissociate SKM cells were established. Using this culture system, the morphological relationship between DRG neurons and SKM cells, neurites growth and neuronal migration were investigated. The migrating neurons were determined by fluorescent labeling of microtubule-associated protein-2 (MAP-2) and neurofilament 200 (NF-200) or growth-associated protein 43 (GAP-43). The expression of NF-200 and GAP-43 and their mRNAs was evaluated by Western blot assay and real time-PCR analysis. The results reveal that DRG explants showed more dense neurites outgrowth in neuromuscular cocultures as compared with that in the culture of DRG explants alone. The number of total migrating neurons (the MAP-2-expressing neurons) and the percentage NF-200-immunoreactive (IR) and GAP-43-IR neurons increased significantly in the presence of SKM cells. The levels of NF-200 and GAP-43 and their mRNAs increased significantly in neuromuscular cocultures as compared with that in the culture of DRG explants alone. These results suggested that target SKM cells play an important role in regulating neuronal protein synthesis, promoting neuritis outgrowth and neuronal migration of DRG explants in vitro. These results not only provide new clues for a better understanding of the association of SKM cells with DRG sensory neurons during development, they may also have implications for axonal regeneration after nerve injury.

Enhanced expression of neuronal proteins in idiopathic frozen shoulder

BACKGROUND

Our understanding of the pathogenesis of frozen shoulder and why it is so painful is undetermined. This study investigated the expression of neuronal proteins in the capsular tissue of frozen shoulder.

METHODS

Shoulder capsular samples were collected from 8 patients with idiopathic adhesive capsulitis and 10 patients with a rotator cuff tear but no stiffness (controls). Samples were analyzed by immunohistochemistry using antibodies against protein gene product 9.5 (PGP9.5), a general nerve marker; growth associated protein 43 (GAP43), a nerve growth marker; nerve growth factor receptor p75; and CD34, an endothelial cell marker.

RESULTS

Samples from frozen shoulders showed subsynovial hypercellularity and fibroblastic proliferation, with increased expression of nerve growth factor receptor p75 and CD34 compared with controls. Nerves positive for PGP9.5 and GAP43 were more abundant in samples of frozen shoulder (2.8 ± 0.2 and 2.4 ± 0.4 per field; P < .01) compared with controls (1.6 ± 0.3 and 1.3 ± 0.3 per field; P < .05). Expression of neuronal proteins followed that of CD34.

CONCLUSION

Increased expression of nerve growth factor receptor and new nerve fibers were found in the shoulder capsular tissue of patients with frozen shoulder compared with those without a frozen shoulder. These data suggest that neoinnervation and neoangiogenesis in the shoulder capsule are important events in the pathogenesis of frozen shoulder and may help explain the often-severe pain of patients with frozen shoulder.

Effect of antiangiogenic treatment on peritoneal endometriosis-associated nerve fibers

OBJECTIVE

To investigate the effect of antiangiogenic treatment on experimental endometriotic lesion nerve fibers.

DESIGN

Heterologous mouse model of endometriosis.

SETTING

University Institute IVI, University Hospital La Fe.

ANIMAL(S)

Ovariectomized nude mice (n = 16) receiving human endometrial fragments from oocyte donors (n = 4).

INTERVENTION(S)

Endometrium fragments stuck in the peritoneum of 5-week-old female nude mice treated with vehicle (n = 8) and antiangiogenic agent cabergoline (n = 8; Cb(2,) 0.05 mg/kg/day) for 14 days.

MAIN OUTCOME MEASURE(S)

Immunofluorescence analysis of von-Willebrand factor (vWF) and vascular smooth muscle cells (αSMA) for evaluating the number of immature blood vessels (IBV) and microvascular density (MVD); immunochemical analysis of protein-gene product 9.5 (PGP 9.5) to assess nerve fibers density (NFD), and blue toluidine staining to confirm presence of mast cells and macrophages in endometriotic lesions.

RESULT(S)

All the results were quantified by morphometric techniques. The IBV, NFD, and number of macrophages and mast cells were statistically significantly decreased in the Cb2-treated group when compared with controls.

CONCLUSION(S)

Antiangiogenic treatment statistically significantly diminishes new blood vessel formation after macrophage, mast cell, and nerve fiber reduction, providing a rationale to test antiangiogenic agents as a novel therapeutic approach to severe pelvic pain associated with human peritoneal endometriosis.

Identification and characterization of novel perivascular adventitial cells in the whole mount mesenteric branch artery using immunofluorescent staining and scanning confocal microscopy imaging

A novel perivascular adventitial cell termed, adventitial neuronal somata (ANNIES) expressing the neural cell adhesion molecule (NCAM) and the vasodilator neuropeptide, calcitonin gene-related peptide (CGRP), exists in the adult rat mesenteric branch artery (MBA) in situ. In addition, we have previously shown that ANNIES coexpress CGRP and NCAM. We now show that ANNIES express the neurite growth marker, growth associated protein-43(Gap-43), palladin, and the calcium sensing receptor (CaSR), that senses changes in extracellular Ca(2+) and participates in vasodilator mechanisms. Thus, a previously characterized vasodilator, calcium sensing autocrine/paracrine system, exists in the perivascular adventitia associated with neural-vascular interface. Images of the whole mount MBA segments were analyzed under scanning confocal microscopy. Confocal analysis showed that the Gap-43, CaSR, and palladin were present in ANNIES about 37 ± 4%, 94 ± 6%, and 80 ± 10% respectively, comparable to CGRP (100%). Immunoblots from MBA confirmed the presence of Gap-43 (48 kD), NCAM (120 and 140 kD), and palladin (90–92 and 140 kD). In summary, CGRP, and NCAM-containing neural cells in the perivascular adventitia also express palladin and CaSR, and coexpress Gap-43 which may participate in response to stress/injury and vasodilator mechanisms as part of a perivascular sensory neural network.

Ovarian endometrioma: severe pelvic pain is associated with deeply infiltrating endometriosis

BACKGROUND

The objective of this study was to evaluate the significance of severe preoperative pain for patients presenting with ovarian endometrioma (OMA).

METHODS

Three hundred consecutive patients with histologically proven OMA were enrolled at a single university tertiary referral centre between January 2004 and May 2010. Complete surgical excision of all recognizable endometriotic lesions was performed for each patient. Pain intensity was assessed with a 10-cm visual analogue scale (VAS). Pain was considered as severe when VAS was ≥ 7. Prospective preoperative assessment of type and severity of pain symptoms (VAS) was compared with the peroperative findings (surgical removal and histological analysis) of endometriomas and associated deeply infiltrating endometriosis. Correlations were sought with univariate analysis and a multiple regression logistic model.

RESULTS

After multiple logistic regression analysis, uterosacral ligaments involvement was related with a high severity of chronic pelvic pain [odds ratios (OR) = 2.1; 95% confidence interval (CI): 1.1-4.3] and deep dyspareunia (OR = 2.0; 95% CI: 1.1-3.5); vaginal involvement was related with a higher intensity of lower urinary symptoms (OR = 13.4; 95% CI: 3.2-55.8); intestinal involvement was related with an increased severity of dysmenorrhoea (OR = 5.2; 95% CI: 2.7-10.3) and gastro-intestinal symptoms (OR = 7.1; 95% CI: 3.3-15.3).

CONCLUSIONS

In case of OMA, severe pelvic pain is significantly associated with deeply infiltrating lesions. In this situation, the practitioner should perform an appropriate preoperative imaging work-up in order to evaluate the existence of associated deep nodules and inform the patient in order to plan the surgical intervention strategy.

Imbalance between sympathetic and sensory innervation in peritoneal endometriosis

To investigate possible mechanisms of pain pathophysiology in patients with peritoneal endometriosis, a clinical study on sensory and sympathetic nerve fibre sprouting in endometriosis was performed. Peritoneal lesions (n=40) and healthy peritoneum (n=12) were immunostained and analysed with anti-protein gene product 9.5 (PGP 9.5), anti-substance P (SP) and anti-tyrosine hydroxylase (TH), specific markers for intact nerve fibres, sensory nerve fibres and sympathetic nerve fibres, respectively, to identify the ratio of sympathetic and sensory nerve fibres. In addition, immune cell infiltrates in peritoneal endometriotic lesions were analysed and the nerve growth factor (NGF) and interleukin (IL)-1β expression was correlate with the nerve fibre density. Peritoneal fluids from patients with endometriosis (n=40) and without endometriosis (n=20) were used for the in vitro neuronal growth assay. Cultured chicken dorsal root ganglia (DRG) and sympathetic ganglia were stained with anti-growth associated protein 43 (anti-GAP 43), anti-SP and anti-TH. We could detect an increased sensory and decreased sympathetic nerve fibres density in peritoneal lesions compared to healthy peritoneum. Peritoneal fluids of patients with endometriosis compared to patients without endometriosis induced an increased sprouting of sensory neurites from DRG and decreased neurite outgrowth from sympathetic ganglia. In conclusion, this study demonstrates an imbalance between sympathetic and sensory nerve fibres in peritoneal endometriosis, as well as an altered modulation of peritoneal fluids from patients with endometriosis on sympathetic and sensory innervation which might directly be involved in the maintenance of inflammation and pain.

Female Perspectives on Endometriosis: Findings from the Uterine Bleeding and Pain Women'S Research Study

Purpose

The symptoms of endometriosis are heterogeneous and overlap with those of other conditions, resulting in misdiagnoses and/or delayed diagnosis and treatment. The Uterine Bleeding and Pain Women's Research Study (UBP-WRS) collected data to elucidate differences in diagnoses and treatment experiences of women, and to assess the impact of endometriosis on their quality of life.

Methods

The UBP-WRS interviewed women aged 15 to 49 in eight countries using an online methodology. Quotas were applied for the age, region, level of education, and income of respondents. Questions assessed menstruation, diagnoses of endometriosis or other gynecological conditions (e.g., uterine fibroids), symptoms, impact on life, and perceptions of treatments.

Results

Of the total of 21 749 women, 2.7% reported surgically diagnosed endometriosis, 2.4% reported nonsurgically diagnosed endometriosis, 5.5% had physician-suspected endometriosis, and 6.2% reported symptoms indicative of endometriosis but no diagnosis. Prevalence of the different diagnoses was comparable between countries. Mean age at diagnosis was 28 years and estimated time-to-diagnosis was 6.1 years. Pain symptoms were generally more common and severe in women with diagnosed endometriosis than in those with suspected disease, whereas the reverse was true for their quality-of-life. Of women receiving treatment for diagnosed endometriosis, 60% were satisfied and 40% were dissatisfied with efficacy. However, 29% of women with diagnosed endometriosis were not receiving any treatment.

Conclusions

Approximately 17% of women in the UBP-WRS reported diagnosed, suspected or symptoms of endometriosis; this is comparable to previously published studies. The UBP-WRS – among the largest surveys of its kind – may help to improve understanding of this enigmatic disease and guide therapeutic practices.

Activation of ERK1/2 and PI3K/Akt by IGF-1 on GAP-43 expression in DRG neurons with excitotoxicity induced by glutamate in vitro

Insulin-like growth factor-1 (IGF-1) is a neurotrophic factor and plays an important role in promoting axonal growth from dorsal root ganglion (DRG) neurons. Whether IGF-1 influences growth-associated protein 43 (GAP-43) expression and activates the extracellular signal-regulated protein kinase (ERK1/2) and the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways in DRG neurons with excitotoxicity induced by glutamate (Glu) remains unknown. In this study, embryonic 15-day-old rat DRG explants were cultured for 48 h and then exposed to IGF-1, Glu, Glu + IGF-1, Glu + IGF-1 + PD98059, Glu + IGF-1 + LY294002, Glu + IGF-1 + PD98059 + LY294002 for additional 12 h. The DRG explants were continuously exposed to growth media as control. The levels of GAP-43 mRNA were detected by real time-PCR analysis. The protein levels of GAP-43, phosphorylated ERK1/2, phosphorylated Akt, total ERK1/2, and total Akt were detected by Western blot assay. GAP-43 expression in situ was determined by immunofluorescent labeling. Apoptotic cell death was monitored by Hoechst 33342 staining. IGF-1 alone increased GAP-43 and its mRNA levels in the absence of Glu. The decreased GAP-43 and its mRNA levels caused by Glu could be partially reversed by the presence of IGF-1. IGF-1 rescued neuronal cell death caused by Glu. Neither the ERK1/2 inhibitor PD98059 nor the PI3K inhibitor LY294002 blocked the effect of IGF-1, but both inhibitors together were effective. To validate the impact of GAP-43 expression by IGF-1, GAP-43 induction was blocked by administration of dexamethasone (DEX). IGF-1 partially rescued the decrease of GAP-43 and its mRNA levels induced by DEX. DEX induced an increase of cell apoptosis. IGF-1 may play an important role in neuroprotective effects on DRG neurons through regulating GAP-43 expression with excitotoxicity induced by Glu and the process was involved in both ERK1/2 and PI3K/Akt signaling pathways.

Endometriosis: the role of neuroangiogenesis

Endometriosis is a common cause of pelvic pain and infertility, affecting ∼10% of reproductive-age women. Annual costs for medical and surgical care in the United States exceed $20 billion. The disorder is characterized by implants of endometrial tissue outside the uterine cavity. Endometriotic lesions induce a state of chronic peritoneal inflammation, accompanied by elevated prostaglandin, cytokine, and growth factor concentrations. The current therapy is surgical ablation of ectopic implants and hormones that block the hypothalamic-pituitary-ovarian axis, but these approaches are expensive, carry perioperative risks, or have unpleasant side effects of hypoestrogenism. Recent evidence indicates that ectopic endometriotic implants recruit their own unique neural and vascular supplies through neuroangiogenesis. It is believed that these nascent nerve fibers in endometriosis implants influence dorsal root neurons within the central nervous system, increasing pain perception in patients. We consider the mechanisms and therapeutic implications of neuroangiogenesis in these lesions and propose potential treatments for the control or elimination of endometriosis-associated pain.

Accumulation of nerve growth factor and its receptors in the uterus and dorsal root ganglia in a mouse model of adenomyosis

BACKGROUND

Adenomyosis is a common gynecological disease, which is accompanied by a series of immunological and neuroendocrinological changes. Nerve growth factor (NGF) plays a critical role in producing pain, neural plasticity, immunocyte aggregation and release of inflammatory factors. This study aimed to investigate the expression of NGF and its two receptors in uteri and dorsal root ganglia (DRG) in an adenomyosis mouse model, as well as their relationship with the severity of adenomyosis.

METHODS

Forty newborn ICR mice were randomly divided into the adenomyosis model group and control group (n = 20 in each group). Mice in the adenomyosis model group were orally dosed with 2.7 μmol/kg tamoxifen on days 2-5 after birth. Experiments were conducted to identify the expression of NGF- beta and its receptors, tyrosine kinase receptor (trkA) and p75 neurotrophin receptor (p75NTR), in the uterus and DRG in four age groups (90+/-5 d, 140+/-5 d, 190+/-5 d and 240+/-5 d; n = 5 mice in each group) by western bolt, immunochemistry and real time reverse transcription-polymerase chain reaction.

RESULTS

Adenomyosis, which became more serious as age increased, was successfully induced in dosed ICR mice. NGF-beta, trkA and p75NTR protein levels in the uterus and trkA mRNA levels in DRG were higher in the older aged adenomyosis model group than those in controls (190+/-5 d and 240+/-5 d groups, P < 0.05). The expression of NGF-beta and its receptors in the uterus increased gradually as age increased for adenomyosis mice (190+/-5 d and 240+/-5 d, P < 0.05, compared with 90+/-5 d) but it showed little change in control mice. The mRNA level of trkA in DRG also increased as age increased in the adenomyosis model group (190+/-5 d and 240+/-5 d, P < 0.05, compared with 90+/-5 d) but was unchanged in controls. The mRNA level of p75NTR in DRG was not different between the adenomyosis and control groups and was stable from young to old mice.

CONCLUSIONS

NGF- beta can be used as an indicator for the severity of adenomyosis. The gradually increasing level of NGF- beta and its receptors while the disease becomes more severe suggests an effect of NGF- beta on pathogenic mechanisms of adenomyosis.

The diagnosis and treatment of deep infiltrating endometriosis

BACKGROUND

Endometriosis and adenomyosis uteri are the most common benign disorders affecting girls and women after uterine myomas (fibroids), with a prevalence of roughly 5% to 15%. There have been many advances in diagnostic assessment and in our understanding of the disease over the past decade. Steady improvements in treatment have been accompanied by heightened consciousness of the diagnosis among the affected women and the doctors who care for them.

METHODS

A selective literature search was carried out in the Cochrane and PubMed databases using the key words "endometriosis," "deep infiltrating endometriosis," "endometriosis AND diagnostics," "endometriosis AND surgical therapy," "endometriosis AND endocrine treatment," and others. The AWMF and ESHRE guidelines were also taken in account.

RESULTS AND CONCLUSION

The main manifestations are primary or secondary dysmenorrhea, bleeding disturbances, infertility, dysuria, pain on defecation (dyschezia), cycle-dependent or (later) cycle-independent pelvic pain, nonspecific cycle-associated gastrointestinal or urogenital symptoms. Cycle-associated problems of urination and/or defecation that are due to endometriosis are most common in young, premenopausal women. Whenever such manifestations are present, endometriosis should be considered in the differential diagnosis, and evidence for it should be sought in the clinical history, physical examination, and ultrasound findings. If endometriosis is histologically confirmed and is of the deeply infiltrating kind, the recommended management today is to refer the patient to an endometriosis center.

Endometriosis and mechanisms of pelvic pain

Endometriosis remains an enigmatic disorder in that the cause, the natural history, and the precise mechanisms by which it causes pain are not completely understood. The pain symptoms most commonly attributed to endometriosis are dysmenorrhea, dyspareunia, and chronic pelvic pain. Pain may be due to nociceptive, inflammatory, or neuropathic mechanisms, and there is evidence that all 3 of these mechanisms are relevant to endometriosis-associated pelvic pain. It is proposed that the clinically observed inconsistencies of the relationships of endometriosis severity and the presence or severity of pain are likely due to variable roles of different pain mechanisms in endometriosis. A better understanding of the roles of nociceptive, inflammatory, and neuropathic pain in endometriosis is likely to improve the treatment of women with endometriosis-associated pelvic pain.

A pilot study to evaluate the clinical relevance of endometriosis-associated nerve fibers in peritoneal endometriotic lesions

OBJECTIVE

To investigate the clinical relevance of endometriosis-associated nerve fibers in the development of endometriosis-associated symptoms.

DESIGN

Prospective nonrandomized study.

SETTING

University hospital endometriosis center.

PATIENT(S)

Fifty-one premenopausal patients underwent surgical laparoscopy because of chronic pelvic pain, dysmenorrhea, or for ovarian cysts. Endometriosis was diagnosed in 44 patients.

INTERVENTION(S)

The preoperative and postoperative pain scores were determined using a standardized questionnaire with a visual analogue scale from 1-10. Patients with peritoneal endometriosis were divided into two groups depending on their preoperative pain score: group A with a pain score of at least 3 or more and group B with a pain score of 2 or less. Patients without peritoneal endometriosis were classified as group C and patients without endometriosis were classified as group D. Immunohistochemical analysis of neurofilament and protein gene product 9.5 were used for nerve fiber detection. Occurrence of endometriosis-associated nerve fibers was correlated with the severity of pelvic pain and/or dysmenorrhea.

RESULT(S)

Peritoneal endometriosis-associated nerve fibers were found significantly more frequently in group A than in group B (82.6% vs. 33.3%).

CONCLUSION(S)

The present study suggests that the presence of endometriosis-associated nerve fibers in the peritoneum is important for the development of endometriosis-associated pelvic pain and dysmenorrhea.