Use of knockout transgenic mice in the study of endometriosis: insights from mice lacking beta(2)-microglobulin and interleukin-12p40

Tetramethylpyrazine Retards the Progression and Fibrogenesis of Endometriosis

The development of more efficacious, non-hormonal therapeutics for endometriosis is still an unmet medical need begging to be fulfilled. Growing evidence indicates that endometriotic lesions are wounds undergoing repeated tissue injury and repair, and, as such, platelets play an important role in lesional progression. Tetramethylpyrazine (TMP), a compound derived from a herb that has been used for thousands of years to combat “blood stasis” in traditional Chinese medicine, is a prescription drug in China for the treatment of cerebrovascular disorders. We tested the hypothesis that TMP can decelerate lesional progression through arresting epithelial-mesenchymal transition (EMT), fibroblast-to-myofibroblast transdifferentiation (FMT), and fibrogenesis. We found in our in vitro experiments that TMP treatment suppresses platelet-induced EMT, FMT, cellular contractility, and collagen production in a concentration-dependent manner. We also showed that in a mouse model of endometriosis, treatment with TMP significantly reduced lesion weight and the extent of lesional fibrosis and improved hyperalgesia, mostly likely through the reduction of lesional aggregation of platelets and the lesional expression of markers of EMT, FMT, and fibrogenesis. In light of our results and in view of its excellent safety profiles, TMP appears to be a promising drug candidate for treating endometriosis.

Changing prostaglandin E2 (PGE2) signaling during lesional progression and exacerbation of endometriosis by inhibition of PGE2 receptor EP2 and EP4

Purpose

We investigated the change, if any, in prostaglandin E2 (PGE₂) signaling in endometriotic lesions of different developmental stages in mouse. In addition, we evaluated the effect of treatment of mice with induced deep endometriosis (DE) with inhibitors of PGE₂ receptor subtypes EP2 and EP4 and metformin.

Methods

Three mouse experimentations were conducted. In Experiment 1, female Balb/C mice were induced with endometriosis or DE and were serially sacrificed after induction. Experiments 2 and 3 evaluated the effect of treatment with EP2 and EP4 inhibitors and metformin, respectively, in mice with induced DE. Immunohistochemistry analysis of COX-2, EP2, and EP4, along with the extent of lesional fibrosis, was evaluated.

Results

The immunostaining of COX-2, EP2, and EP4 turned from activation to a stall as lesions progressed. Treatment with EP2/EP4 inhibitors in DE mice exacerbated endometriosis-associated hyperalgesia and promoted fibrogenesis in lesions even though it suppressed the PGE₂ signaling dose-dependently. In contrast, treatment with metformin resulted in increased PGE₂ signaling, concomitant with improved hyperalgesia, and retarded lesional fibrogenesis.

Conclusions

The PGE₂ signaling diminishes as endometriotic lesions progress. Treatment with EP2/EP4 inhibitors in DE mice exacerbates endometriosis, but metformin appears to be promising seemingly through the induction of the PGE₂ signaling.

Gut microbiota-derived short-chain fatty acids protect against the progression of endometriosis

Worldwide, ∼196 million are afflicted with endometriosis, a painful disease in which endometrial tissue implants and proliferates on abdominal peritoneal surfaces. Theories on the origin of endometriosis remained inconclusive. Whereas up to 90% of women experience retrograde menstruation, only 10% develop endometriosis, suggesting that factors that alter peritoneal environment might contribute to endometriosis. Herein, we report that whereas some gut bacteria promote endometriosis, others protect against endometriosis by fermenting fiber to produce short-chain fatty acids. Specifically, we found that altered gut microbiota drives endometriotic lesion growth and feces from mice with endometriosis contained less of short-chain fatty acid and n-butyrate than feces from mice without endometriosis. Treatment with n-butyrate reduced growth of both mouse endometriotic lesions and human endometriotic lesions in a pre-clinical mouse model. Mechanistic studies revealed that n-butyrate inhibited human endometriotic cell survival and lesion growth through G-protein-coupled receptors, histone deacetylases, and a GTPase activating protein, RAP1GAP. Our findings will enable future studies aimed at developing diagnostic tests, gut bacteria metabolites and treatment strategies, dietary supplements, n-butyrate analogs, or probiotics for endometriosis.

Preoperative and perioperative intervention reduces the risk of recurrence of endometriosis in mice caused by either incomplete excision or spillage and dissemination

RESEARCH QUESTION

Can preoperative or perioperative intervention reduce the risk of recurrence of endometriosis caused by either incomplete excision or spillage and dissemination?

DESIGN

A mouse model of endometriosis recurrence caused by spillage and dissemination was first established using 24 female Balb/c mice. The spillage and dissemination model was used to test the efficacy of preoperative use of ketorolac, perioperative use of aprepitant and combined use of propranolol and andrographolide in a prospective, randomized mouse experiment involving 75 mice. The efficacy of these preoperative and perioperative interventions in a mouse recurrence model caused by incomplete excision was also tested using 72 mice. In all experiments, the baseline body weight and hotplate latency of all mice were measured and recorded before the induction of endometriosis, before the primary surgery and before sacrifice. In addition, all lesions were excised, weighed and processed for quantification and immunohistochemistry analysis of E-cadherin, α-SMA, VEGF, ADRB2 and putative markers of recurrence PR-B, p-p65, as well as Masson trichrome staining.

RESULTS

All interventions substantially and significantly suppressed the outgrowth of endometriotic lesions and reduced the risk of recurrence caused by either spillage and dissemination or incomplete excision (P = 0.0007 to 0.042). These interventions also significantly attenuated the generalized hyperalgesia, inhibited the staining of α-SMA, p-p65, VEGF and ADRB2 but increased staining of E-cadherin and PR-B, resulting in reduced fibrosis.

CONCLUSION

Given the excellent safety profiles of these drugs, these data strongly suggest that preoperative and perioperative intervention may potentially reduce the risk of endometriosis recurrence effectively.

Sodium tanshinone IIA sulfonate restrains fibrogenesis through induction of senescence in mice with induced deep endometriosis

RESEARCH QUESTION

Does sodium tanshinone IIA sulfonate (STS) induce cellular senescence in endometriotic lesions and thus restrict lesional development and fibrogenesis in a recently established mouse model of deep endometriosis?

DESIGN

Prospective randomized animal experiment in which deep endometriosis was induced in female Balb/C mice, which were then randomly divided into three groups (low-dose STS, high-dose STS and inert vehicle control) and received treatment for 2 weeks. All mice were then sacrificed and their lesions excised and harvested. Lesion weight was quantified and all lesion samples were subjected to histochemical analysis of the extent of lesional fibrosis by Masson trichrome staining, and of cellular senescence by senescence-associated β-galactosidase (SA-β-gal), along with immunohistochemistry analyses of p53, CCN1, activate Salvador 1 (Sav1), hyaluronan synthase 2 (HAS2), survivin, granulocyte-macrophage colony-stimulating factor (GM-CSF) and CD163-positive M2 macrophages. Plasma P-selectin and hyaluronic acid levels were also quantified. Hotplate testing was also administered before the induction, then before and after treatment.

RESULTS

STS treatment resulted in significantly reduced lesion weight, stalled lesional fibrogenesis and improved hyperalgesia, seemingly through the induction of cellular senescence by activating p53, Sav1 and CCN1 while suppressing HAS2, survivin and GM-CSF, resulting in increased apoptosis and reduced lesional infiltration of alternatively activated macrophages. In addition, STS treatment significantly reduced the plasma concentration of P-selectin and hyaluronic acid, possibly leading to reduced lesional platelet aggregation.

CONCLUSIONS

STS appears to be a promising compound for treating endometriosis. The results suggest that senescence may restrict lesional progression and fibrogenesis, and targeting the senescence pathway may have desirable therapeutic potential.

Early maternal separation accelerates the progression of endometriosis in adult mice

BACKGROUND

A large body of research highlights the importance of early-life environmental impact on the health outcome in adulthood. However, whether early-life adversity (ELA) has any impact on the development of endometriosis is completely unclear. In this study, we tested the hypothesis that ELA, as manifested by neonatal separation, can accelerate the progression of endometriosis in mouse through activation of the adrenergic receptor β2 (ADRB2) signaling pathway, leading to increased angiogenesis and progression of endometriotic lesions.

METHODS

Eight female Balb/C mice, in late pregnancy, were used used for this study, which later gave birth to 22 female newborn pubs. Eleven additional female Balb/C mice were also used as donors of uterine tissues. The 22 newborn pubs were randomly divided into 2 equal-sized groups, maternal separation (MS) and no separation (NS). Pubs in the MS group were separated from their dams for 3 h/day from postnatal day (PND) 1 to 21, while those in the NS control remained in the home cage with their dams. In adulthood (8-week old), 3 mice in each group were randomly selected to undergo a battery of behavior tests. The remaining 8 mice in each group were induced with endometriosis by intraperitoneal injection of uterine fragments from donor mice. Four weeks after the induction, all mice were sacrificed and their endometriotic lesions were excised for quantification and then prepared for immunohistochemistry analysis.

RESULTS

We confirmed that MS during infancy resulted in anxiety and depression-like behaviors as previously reported. We also found that in MS mice the lesion weight was increased by over 2 folds and generalized hyperalgesia was also significantly increased as compared with NS mice. Immunostaining analysis demonstrated that MS accelerated the development of endometriosis likely through decreased dopamine receptor D2 (DRD2) expression and activation of the ADRB2/cAMP-response element binding protein (CREB) signaling pathway, leading to increased angiogenesis and progression of endometriotic lesions.

CONCLUSIONS

Exposure of female mouse pups to ELA such as MS during their infancy period accelerates the progression of endometriosis, possibly through altered neuronal wiring and hyperactivity of the hypothalamic-pituitary-adrenal axis.

Platelets induce increased estrogen production through NF-κB and TGF-β1 signaling pathways in endometriotic stromal cells

Endometriosis is estrogen-dependent disorder. Two theories provide the explanations for the increased estrogen production. One is the feed-forward loop model linking inflammation and estrogen production. The more recent model evokes the tissue hypoxia resulting from endometrial debris detached and then regurgitated to the peritoneal cavity. Both models tacitly assume that everything occurs within the endometriotic stromal cells, seemingly without the need for exogenous factors. This study was undertaken to investigate as whether platelets may be responsible for local estrogen overproduction. We employed in vitro experimentation that evaluated the 17β-estradiol (E₂) levels in endometriotic stromal cells treated with activated platelets, and the genes and protein expression levels of StAR, HSD3B2, aromatase, and HSD17B1, as well as their upstream genes/proteins such as NF-κB, TGF-β1, HIF-1α, SF-1 and phosphorylated CREB. In addition, we conducted 2 animal experimentations using platelet depletion/infusion and also neutralization of NF-κB and TGF-β1, followed by immunohistochemistry analysis of involved in StAR, HSD3B2, aromatase, and HSD17B1, as well as SF-1 and p-CREB. We found that treatment of endometriotic stromal cells by activated platelets increase the E₂ production by 4.5 fold, and concomitant with increased gene and protein expression of StAR, HSD3B2, aromatase, and HSD17B1, the four genes/enzymes important to estrogen synthesis, along with their upstream genes HIF-1α, SF-1 and phosphorylated CREB. Moreover, platelets activate these genes through the activation of NF-κB and/or TGF-β1, and antagonism of either signaling pathway can abolish the induction of the 4 genes and thus increased estrogen production. The two animal experimentations confirmed these changes. Thus, platelets increase the E₂ production in endometriotic stromal cells through upregulation of StAR, HSD3B2, aromatase, and HSD17B1 via the activation of NF-κB and/or TGF-β1. These findings provide a yet another compelling piece of evidence that endometriotic lesions are indeed wounds undergoing repeated tissue injury and repair. They strongly indicate that non-hormonal therapeutics for endometriosis is theoretically viable, with anti-platelet therapy being one promising avenue.

The M2a macrophage subset may be critically involved in the fibrogenesis of endometriosis in mice

RESEARCH QUESTION

Recent research has shown that endometriotic lesions are essentially wounds that undergo repeated tissue injury and repair, which results in epithelial-mesenchymal transition, fibroblast-to-myofibroblast transdifferentiation, smooth muscle metaplasia and ultimately fibrosis. Macrophages are a key regulator of tissue repair and fibrogenesis. But do macrophages also play a role in fibrogenesis of endometriosis, and, if yes, which subset of macrophages?

DESIGN

To elucidate the role of macrophages in fibrogenesis of endometriosis, we conducted three experiments in mice. In experiment 1, endometriotic tissue samples from female Balb/C mice with induced endometriosis were serially harvested to evaluate the role of macrophages in fibrogenesis. In experiments 2 and 3, female transgenic mice (C57BL/6J background) expressing the human diphtheria toxin receptor under the control of the CD11b promoter had macrophage depletion by diphtheria toxin injection after induction of endometriosis. Additionally, in experiment 3, adoptive transfer of different subsets of macrophage was carried out after macrophage depletion.

RESULTS

Lesional infiltration of M2 macrophages increased progressively as lesions progressed undisturbed, concomitant with progressive epithelial-mesenchymal transition, fibroblast-to-myofibroblast transdifferentiation and fibrosis. Macrophage depletion after induction of endometriosis significantly reduced lesional infiltration of total macrophages, significantly reduced lesional infiltration of M2 macrophages and significantly reduced lesional fibrotic content and lesion weight (P < 0.05). Finally, adoptive transfer of M2a, but not M1 or M2c macrophages, systemically after macrophage depletion significantly increased the extent of fibrosis in lesions (P = 1.6 × 10^-10).

CONCLUSIONS

The identification of a particular macrophage subset in fibrogenesis of endometriosis should further help to shed new light on the pathophysiology of endometriosis.

Progressive development of endometriosis and its hindrance by anti-platelet treatment in mice with induced endometriosis

We have recently shown that platelets drive smooth muscle metaplasia (SMM) and fibrogenesis in endometriosis through epithelial-mesenchymal transition (EMT) and fibroblast-to-myofibroblast transdifferentiation (FMT). To see whether this is true in vivo, this prospective, randomized, and serially evaluated mouse investigation was conducted. Endometriosis was induced in female Balb/C mice, which were then randomly divided into two groups: Tanshinone IIA (TAN) and control (CTL) groups. TAN mice were treated with TAN but CTL mice received none. Every week until the 6th week after induction, five mice from each group were killed. Lesion weight was measured and lesion samples were subjected to immunohistochemistry and histochemistry analysis of platelet aggregation (CD41), E-cadherin, TGF-β1, phosphorylated Smad3, α-SMA, collagen I, CCN2, LOX, desmin and SM-MHC, and the extent of fibrosis was evaluated by Masson trichrome staining. It was found that endometriotic lesions exhibited progressive cellular changes consistent with the progressive EMT, FMT, SMM, and fibrogenesis. TAN treatment resulted in significant hindrance of EMT, FMT, SMM and fibrogenesis, and reduced lesion weight (all P-values <0.05). These data corroborate the notion that endometriotic lesions undergo progressive EMT and FMT, giving rise to SMM and ultimately fibrosis. This understanding sheds new light onto the natural history of endometriosis.

Chronic stress accelerates the development of endometriosis in mouse through adrenergic receptor β2

STUDY QUESTION

Does chronic stress in mice accelerate the development of endometriosis, and, if so, through what mechanism?

SUMMARY ANSWER

Exposure to chronic stress accelerates the development of endometriosis and exacerbates the endometriosis-associated generalized hyperalgesia, most likely through activation of the adrenoceptor β2 (ADRB2) and cAMP responsive element-binding protein (CREB).

WHAT IS KNOWN ALREADY

Women with endometriosis tend to have higher levels of psychological stress, which is known to impact negatively on health in general and to promote tumor growth and metastasis in particular. Exposure to chronic stress before and after the induction of endometriosis is reported to increase lesion sizes in rodents, but it is unclear whether adrenoceptors are involved or not in the stress-promoted development of endometriosis.

STUDY DESIGN, SIZE, DURATION

Three independent, prospective, randomized mouse experimentations. A total of 184 virgin female Balb/C mice were used.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In Experiment 1, the mice were randomly divided into four groups: the control group, which received no stress; the before, after and both groups, which received immobilization stress before, after and both before and after the induction of endometriosis, respectively. In Experiment 2, mice were randomly divided into four groups one day after the induction of endometriosis: phosphate buffer saline (PBS) and propranolol (PROP) groups, which received the mini-pump containing, respectively, PBS only and propranolol (a non-selective ADRB antagonist) but no stress, STR+PROP and STR+PBS groups, which received stress and the mini-pump containing, respectively, propranolol and PBS. The immobilization stress started after the insertion of mini-pumps. In Experiment 3, mice were induced with endometriosis. Three days after the induction, they were randomly divided into four groups: control, ADRAa, ADRB2a, and ADRBa, which received the mini-pump containing solution only, metaraminol (a non-specific α adrenoceptor agonist), tebutaline (a specific ADRB2 agonist), or isoproterenol (a non-specific ADRB agonist), respectively. In all three experiments, the bodyweight and hotplate latency were evaluated before sacrifice 14 days after the induction. In all experimentations, the lesion weight was evaluated and the harvested ectopic endometrial tissue samples were subjected to immunohistochemistry analysis of vascular endothelial growth factor (VEGF), CD31-positive microvessels, proliferating cell nuclear antigen (PCNA), phosphorylated CREB, ADRB1, ADRB2, ADRB3, adrenergic receptor α1 (ADRA1) and ADRA2.

MAIN RESULTS AND THE ROLE OF CHANCE

Exposure to chronic stress accelerated the development of endometriosis and exacerbated the endometriosis-associated generalized hyperalgesia. This promotional effect is likely to be mediated through the systemic activation of the sympatho-adreno-medullary (SAM) axis, which results in subsequent release of catecholamines. The surging catecholamines may activate ADRB2 and CREB, yielding increased angiogenesis and cellular proliferation in ectopic endometrium in mice with induced endometriosis. In addition, β adrenergic receptor blockade completely abolished the promotional effect of chronic stress, likely through suppression of ADRB2 and CREB activation, thus suppressing angiogenesis and proliferation. Moreover, a non-specific adrenergic β agonist and a specific adrenergic β2 agonist, but not non-specific adrenergic α agonist, acted similarly to chronic stress, accelerating the development of endometriosis and exacerbating the generalized hyperalgesia in mice with pre-existing endometriosis.

LARGE SCALE DATA

NA.

LIMITATIONS, REASONS FOR CAUTION

This study is limited by the use of immunohistochemistry analyses only and the lack of molecular data.

WIDER IMPLICATIONS OF THE FINDINGS

The present study provides the experimental evidence that chronic stress can promote the development of endometriosis through the activation of ADRB2. Given ADRB2 is also expressed in human endometriosis and appears to be functional, and in light of recent awareness that adrenergic signaling plays critical roles in tumorigenesis, it is likely that adrenergic signaling may play important roles in the development of endometriosis and is potentially a target for intervention.

STUDY FUNDING/COMPETING INTERESTS

This research was supported in part by grants (81270676,  81471434 and 81530040  to S.W.G.;  81370695 and 81671436  to X.S.L.) from the National Natural Science Foundation of China, and grant (2013ZYJB0019 to X.S.L.) from Shanghai Municipal Commission of Health and Family Planning. None of the authors has anything to disclose.

Surgery accelerates the development of endometriosis in mice

BACKGROUND

Surgery is currently the mainstay treatment for solid tumors and many benign diseases, including endometriosis, and women tend to receive substantially more surgeries than men mainly because of gynecological and cosmetic surgeries. Despite its cosmetic, therapeutic, or even life-saving benefits, surgery is reported to increase the cancer risk and promotes cancer metastasis. Surgery activates adrenergic signaling, which in turn suppresses cell-mediated immunity and promotes angiogenesis and metastasis. Because immunity, angiogenesis, and invasiveness are all involved in the pathophysiology of endometriosis, it is unclear whether surgery may accelerate the development of endometriosis.

OBJECTIVE

The objective of the study was to test the hypothesis that surgery activates adrenergic signaling, increases angiogenesis, and accelerates the growth of endometriotic lesions.

STUDY DESIGN

This was a prospective, randomized experimentation. The first experiment used 42 female adult Balb/C mice, and the second used 90 female adult Balb/C mice. In experiment 1, 3 days after the induction of endometriosis, mice were randomly divided into 3 groups of approximately equal sizes, control, laparotomy, and mastectomy. In experiment 2, propranolol infusion via Alzet pumps was used to forestall the effect of sympathetic nervous system activation by surgery. In both experiments, mice were evaluated 2 weeks after surgery. Lesion size, hotplate latency, and immunohistochemistry analysis of vascular endothelial growth factor, CD31-positive microvessels, proliferating cell nuclear antigen, phosphorylated cyclic adenosine monophosphate-responsive element-binding protein, β2-adrenergic receptor (ADRB)-2, ADRB1, ADRB3, ADRA1, and ADRA2 in ectopic implants.

RESULTS

Both mastectomy and laparotomy increased lesion weight and exacerbated hyperalgesia, increased microvessel density and elevated the immunoreactivity against ADRB2, phosphorylated cyclic adenosine monophosphate-responsive element-binding protein, vascular endothelial growth factor, and proliferating cell nuclear antigen but not ADRB1, ADRB3, ADRA1, and ADRA2, suggesting activated adrenergic signaling, increased angiogenesis, and accelerated growth of endometriotic lesions. β-Blockade completely abrogated the facilitory effect of surgery, further underscoring the critical role of β-adrenergic signaling in mediating the effect of surgery.

CONCLUSION

Surgery activates adrenergic signaling, increases angiogenesis, and accelerates the growth of endometriotic lesions in the mouse, but such a facilitory effect of surgery can be completely abrogated by β-blockade. Whether surgery can promote the development of endometriosis in humans warrants further investigation.

Endometriosis, a disease of the macrophage

Endometriosis, a common cause of pelvic pain and female infertility, depends on the growth of vascularized endometrial tissue at ectopic sites. Endometrial fragments reach the peritoneal cavity during the fertile years: local cues decide whether they yield endometriotic lesions. Macrophages are recruited at sites of hypoxia and tissue stress, where they clear cell debris and heme-iron and generate pro-life and pro-angiogenesis signals. Macrophages are abundant in endometriotic lesions, where are recruited and undergo alternative activation. In rodents macrophages are required for lesions to establish and to grow; bone marrow-derived Tie-2 expressing macrophages specifically contribute to lesions neovasculature, possibly because they concur to the recruitment of circulating endothelial progenitors, and sustain their survival and the integrity of the vessel wall. Macrophages sense cues (hypoxia, cell death, iron overload) in the lesions and react delivering signals to restore the local homeostasis: their action represents a necessary, non-redundant step in the natural history of the disease. Endometriosis may be due to a misperception of macrophages about ectopic endometrial tissue. They perceive it as a wound, they activate programs leading to ectopic cell survival and tissue vascularization. Clearing this misperception is a critical area for the development of novel medical treatments of endometriosis, an urgent and unmet medical need.

Proangiogenic Tie2(+) macrophages infiltrate human and murine endometriotic lesions and dictate their growth in a mouse model of the disease

Endometriosis affects women of reproductive age, causing infertility and pain. Although immune cells are recruited in endometriotic lesions, their role is unclear. Tie2-expressing macrophages (TEMs) have nonredundant functions in promoting angiogenesis and growth of experimental tumors. Here we show that human TEMs infiltrate areas surrounding newly formed endometriotic blood vessels. We set up an ad hoc mouse model in which TEMs, and not Tie2-expressing endothelial cells, are targeted. We transplanted in wild-type recipients bone marrow cells expressing a suicide gene (Herpes simplex virus type 1 thymidine kinase) under the Tie2 promoter/enhancer. TEMs infiltrated endometriotic lesions. TEM depletion by ganciclovir administration arrested the growth of established lesions, without toxicity. Lesion architecture was disrupted, with: i) loss of glandular organization, ii) reduced neovascularization, and iii) activation of caspase 3 in CD31(+) endothelial cells. Thus, TEMs are important for maintaining the viability of newly formed vessels and represent a potential therapeutic target in endometriosis.

Macrophages are alternatively activated in patients with endometriosis and required for growth and vascularization of lesions in a mouse model of disease

The mechanisms that sustain endometrial tissues at ectopic sites in patients with endometriosis are poorly understood. Various leukocytes, including macrophages, infiltrate endometriotic lesions. In this study, we depleted mouse macrophages by means of either clodronate liposomes or monoclonal antibodies before the injection of syngeneic endometrial tissue. In the absence of macrophages, tissue fragments adhered and implanted into the peritoneal wall, but endometriotic lesions failed to organize and develop. When we depleted macrophages after the establishment of endometriotic lesions, blood vessels failed to reach the inner layers of the lesions, which stopped growing. Macrophages from patients with endometriosis and experimental mice, but not nonendometriotic patients who underwent surgery for uterine leiomyomas or control mice, expressed markers of alternative activation. These markers included high levels of scavenger receptors, CD163 and CD206, which are involved in both the scavenging of hemoglobin with iron transfer into macrophages and the silent clearance of inflammatory molecules. Macrophages in both inflammatory liquid and ectopic lesions were equally polarized, suggesting a critical role of environmental cues in the peritoneal cavity. Adoptively transferred, alternatively activated macrophages dramatically enhanced endometriotic lesion growth in mice. Inflammatory macrophages effectively protected mice from endometriosis. Therefore, endogenous macrophages involved in tissue remodeling appear as players in the natural history of endometriosis, required for effective vascularization and ectopic lesion growth.

Differentially expressed genes in eutopic and ectopic endometrium of women with endometriosis

OBJECTIVE

To elucidate the potential mechanisms involved in the physiopathology of endometriosis. We analyzed the differential gene expression profiles of eutopic and ectopic tissues from women with endometriosis.

DESIGN

Prospective laboratory study.

SETTING

University hospital.

PATIENT(S)

Seventeen patients in whom endometriosis was diagnosed and 11 healthy fertile women.

INTERVENTION(S)

Endometrial biopsy specimens from the endometrium of healthy women without endometriosis and from the eutopic and ectopic endometrium tissues of patients with endometriosis were obtained in the early proliferative phase of the menstrual cycle.

MAIN OUTCOME MEASURE(S)

Six paired samples of eutopic and ectopic tissue were analyzed by subtractive hybridization. To evaluate the expression of genes found by rapid subtraction hybridization methods, we measured CTGF, SPARC, MYC, MMP, and IGFBP1 genes by real-time polymerase chain reaction in all samples.

RESULT(S)

This study identified 291 deregulated genes in the endometriotic lesions. Significant expression differences were obtained for SPARC, MYC, and IGFBP1 in the peritoneal lesions and for MMP3 in the ovarian endometriomas. Additionally, significant differences were obtained for SPARC and IGFBP1 between the peritoneal and ovarian lesions. No significant differences were found for the studied genes between the control and the eutopic endometrium.

CONCLUSION(S)

This study identified 291 genes with differential expression in endometriotic lesions. The deregulation of the SPARC, MYC, MMP3, and IGFBPI genes may be responsible for the loss of cellular homeostasis in endometriotic lesions.

Interleukin (IL)-12 receptor beta1 codon 378 G homozygote and allele, but not IL-1 (beta-511 promoter, 3953 exon 5, receptor antagonist), IL-2 114, IL-4-590 intron 3, IL-8 3'-UTR 2767, and IL-18 105, are associated with higher susceptibility to leiomyoma

OBJECTIVE

To investigate whether certain polymorphisms are correlated with leiomyoma susceptibility, i.e., interleukin (IL)-1, IL-2, IL-4, IL-8, IL-12, and IL-18, which are all immunomodulatory cytokines that play important roles in host immune responses against cancers.

SETTING

Departments of gynecology and genetics in a medical center.

PATIENT(S)

Women were divided into: [1] a leiomyoma group (n = 162) and [2] a nonleiomyoma group (n = 156).

INTERVENTION(S)

Genotyping for the IL-1beta-511 promoter, IL-1beta exon 5, IL-1Ra, IL-2 114, IL-4 -590 intron 3, IL-8 3'-UTR 2767, IL-12Rbeta1 codon 378, and IL-18 105 were evaluated by polymerase chain reaction-restriction fragment length polymorphism.

MAIN OUTCOME MEASUREMENT(S)

Genotypes and allelic frequencies in both groups were compared.

RESULT(S)

Proportions of IL-12Rbeta1 codon 378 *CC/CG/GG in the leiomyoma and nonleiomyoma groups were: [1] 7.4%/43.8%/48.8% and [2] 11.5%/54.5%/34%, respectively. Distributions of other polymorphisms in both groups were not significantly different. Proportions of IL-1beta-511 promoter *CC/CT/TT were: [1] 22.8%/50%/27.2% and [2] 21.8%/57.1%/21.1% in the leiomyoma and nonleiomyoma groups, respectively. The IL-1beta exon 5 *E1 homozygote/heterozygote/E2 homozygote were: [1] 96.3%/3.7%/0% and [2] 96.9%/3.1%/0% in the leiomyoma and nonleiomyoma groups, respectively. Alleles I/II/III/IV/V for IL-1Ra were: [1] 92.6%/7.1%/0.3%/0/0% and [2] 93.9%/5.7%/0%/0.4/0% in the leiomyoma and nonleiomyoma groups, respectively. The IL-2 114 G homozygote/heterozygote/T homozygote were: [1] 27.8%/49.4%/22.8% and [2] 20.5%/53.2%/26.3% in the leiomyoma and nonleiomyoma groups, respectively. The IL-4 -590 intron 3 *RP1 homozygote/heterozygote/RP2 homozygote were: [1] 64.8%/32.7%/2.5% and [2] 69.2%/26.9%/3.9% in the leiomyoma and nonleiomyoma groups, respectively. The IL-8 3'-UTR 2767 A homozygote/heterozygote/G homozygote were: [1] 14.2%/43.8%/42% and [2] 20.5%/41.7%/37.8% in the leiomyoma and nonleiomyoma groups, respectively. The IL-18 *AA/AC/CC were: [1] 56.8%/40.7%/2.5% and [2] 59%/39.7%/1.3% in the leiomyoma and nonleiomyoma groups, respectively.

CONCLUSION(S)

The IL-12Rbeta1 codon 378 *G homozygote and G allele are related to a higher susceptibility to leiomyoma. The IL-1beta-511 promoter, IL-1beta exon 5, and IL-1Ra, IL-2 114, IL-4 -590 intron 3, IL-8 3'-UTR 2767, and IL-18 105 gene polymorphisms are not correlated with the development of leiomyoma.

HpaA is essential for Helicobacter pylori colonization in mice

Infection with the human gastric pathogen Helicobacter pylori can give rise to chronic gastritis, peptic ulcer, and gastric cancer. All H. pylori strains express the surface-localized protein HpaA, a promising candidate for a vaccine against H. pylori infection. To study the physiological importance of HpaA, a mutation of the hpaA gene was introduced into a mouse-adapted H. pylori strain. To justify that the interruption of the hpaA gene did not cause any polar effects of downstream genes or was associated with a second site mutation, the protein expression patterns of the mutant and wild-type strains were characterized by two different proteomic approaches. Two-dimensional differential in-gel electrophoresis analysis of whole-cell extracts and subcellular fractionation combined with nano-liquid chromatography-Fourier transform ion cyclotron resonance mass spectrometry for outer membrane protein profiling revealed only minor differences in the protein profile between the mutant and the wild-type strains. Therefore, the mutant strain was tested for its colonizing ability in a well-established mouse model. While inoculation with the wild-type strain resulted in heavily H. pylori-infected mice, the HpaA mutant strain was not able to establish colonization. Thus, by combining proteomic analysis and in vivo studies, we conclude that HpaA is essential for the colonization of H. pylori in mice.

Quantification of endometriotic lesions in a murine model by fluorimetric and morphometric analyses

BACKGROUND

In animal models of endometriosis, the identification and quantification of lesions originating from human endometrium is often hampered by the small size of the implants and their embedding in murine tissue. The purpose of the present study was to develop two new methods of quantifying endometriosis-like lesions in a nude mouse model: fluorimetry and morphometry.

METHODS

Human menstrual endometrium was labelled using a fluorescent tracker, carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE), and transplanted into the pelvic cavity of mice by injection through the peritoneum after performing a cutaneous incision. After 5 days, lesions were recovered by laparotomy. The fluorescence of the recovered endometriotic lesions was measured. Endometrial stroma and glands were immunostained in lesion sections with anti-CD10 and anti-CK22 antibodies, and their surface area was evaluated by morphometric analysis.

RESULTS

Fluorescent labelling allows identification of lesions not visible macroscopically. A good correlation was observed between fluorimetry and morphometry (r=0.88) applied for lesion quantification.

CONCLUSIONS

Fluorimetric evaluation combined with morphometric analysis of endometriosis-like lesions allows objective and reliable recording of endometriosis development in a nude mouse model. This quantification method could therefore be useful for future pharmacological and toxicological studies.

Transcriptional regulation of Na+/H+ exchanger expression in the intact mouse

We examined regulation of the Na+/H+ exchanger (NHE1 isoform) in the developing mouse. We generated transgenic mice with the Na+/H+ exchanger promoter directing expression of the beta-Galactosidase reporter. We found that expression of the Na+/H+ exchanger was maximum in the heart and liver of 12-day-old embryonic mice. Similar results were found in mice using the green fluorescent protein reporter driven by the Na+/H+ exchanger promoter. Detailed examination of the myocardium revealed that the GFP reporter protein was expressed in the cytoplasm of cardiomyocyte cells. We examined NHE1 protein expression in transgenic mice lacking the transcription factors AP-2alpha or the transcription factor COUP-TF1. Eighteen-day-old AP-2alpha heterozygote mice show no large changes in NHE1 expression in heart, lung, liver, kidney and brain. In contrast, 18-day-old embryos from AP-2alpha null mice showed a large increase in Na+/H+ exchanger protein expression in the brain. NHE1 protein levels in COUP-TF1 knockout embryos did not differ from wild type embryos. The results suggest that AP-2alpha and COUP-TF1 are not critical to NHE1 expression in the late stage embryo and that other related transcription factors may function in regulation of the Na+/H+ exchanger.