Ductular reaction promotes intrahepatic angiogenesis through Slit2-Roundabout 1 signaling.

BACKGROUND AND AIMS: Ductular reaction (DR) expands in chronic liver diseases and correlates with disease severity. Besides its potential role in liver regeneration, DR plays a role in the wound-healing response of the liver, promoting periductular fibrosis and inflammatory cell recruitment. However, there is no information regarding its role in intrahepatic angiogenesis. In the current study we investigated the potential contribution of DR cells to hepatic vascular remodeling during chronic liver disease. APPROACH AND RESULTS: In mouse models of liver injury, DR cells express genes involved in angiogenesis. Among angiogenesis-related genes, the expression of Slit2 and its receptor Roundabout 1 (Robo1) was localized in DR cells and neoangiogenic vessels, respectively. The angiogenic role of the Slit2-Robo1 pathway in chronic liver disease was confirmed in ROBO1/2-/+ mice treated with 3,5-diethoxycarbonyl-1,4-dihydrocollidine, which displayed reduced intrahepatic neovascular density compared to wild-type mice. However, ROBO1/2 deficiency did not affect angiogenesis in partial hepatectomy. In patients with advanced alcohol-associated disease, angiogenesis was associated with DR, and up-regulation of SLIT2-ROBO1 correlated with DR and disease severity. In vitro, human liver-derived organoids produced SLIT2 and induced tube formation of endothelial cells. CONCLUSIONS: Overall, our data indicate that DR expansion promotes angiogenesis through the Slit2-Robo1 pathway and recognize DR cells as key players in the liver wound-healing response.

Erratum: Andrographolide Suppress Tumor Growth by Inhibiting TLR4/NF-κB Signaling Activation in Insulinoma: Erratum.

[This corrects the article DOI: 10.7150/ijbs.7723.].

Slit2 Promotes Angiogenic Activity Via the Robo1-VEGFR2-ERK1/2 Pathway in Both In Vivo and In Vitro Studies.

PURPOSE: Recent research has provided novel but contrary insight into the function of Slit2-Robo signaling in angiogenesis. Although the role of Robo in choroidal neovascularization (CNV) has been studied, the effect of its ligand, Slit2, on CNV development is unclear. This study investigated the role of endogenous Slit2 in CNV and the possible mechanisms. METHODS: Laser-induced CNV in Slit2 transgenic and wild-type mice was used to study the effects of endogenous Slit2 on angiogenesis in vivo. Fluorescein angiography was performed to evaluate the leakage area of each lesion. Plasmid-based gene transfer technology was used to increase Slit2 expression and to study its effects on human umbilical vein endothelial cells (HUVECs) in vitro. Cell proliferation, migration, and tube formation were assessed. Quantitative real-time PCR and Western blot were used to measure expression in the extracellular signal-related kinase 1/2 (ERK1/2), protein kinase B (AKT), and p38 mitogen-activated protein kinase (p38 MAPK) molecular pathways. RESULTS: Laser treatment led to more CNV and vascular leakage in Slit2 transgenic mice compared with wild-type mice. Upregulation of Slit2, Robo1, VEGF receptor 2 (VEGFR2), and phosphorylated ERK1/2 (p-ERK1/2) were detected in retina and choroidal tissue of laser-treated transgenic mice. After transfection of HUVECs with a Slit2 overexpression plasmid, cell proliferation, migration, and tube formation capacities were promoted. Slit2, Robo1, VEGFR2, and p-ERK1/2 were elevated in transfected HUVECs. CONCLUSION: Slit2 overexpression promoted angiogenic effects in both a laser-induced CNV mouse model and HUVECs and promoted the biological activity of endothelial cells. Slit2 may promote angiogenesis by upregulating Robo1 and activating the VEGFR2-ERK1/2 pathway.

P-selectin as a potential therapeutic target for endometriosis.

OBJECTIVE: To test the hypothesis that P-selectin plays a critical role in the development of endometriosis and that targeting P-selectin has therapeutic potential. DESIGN: Prospective, randomized study. SETTING: Academic facility. ANIMAL(S): The first experiment used 24 each of female adult P-selectin knockout mice and C57BL/6 wild-type mice, and 96 male green fluorescent protein (GFP) transgenic mice. The second experiment used 16 female adult C57BL/6 mice. INTERVENTION(S): In experiment 1, P-selectin knockout and wild-type mice alternately served as donors and recipients for the transplantation of endometrial tissue fragments into the peritoneal cavity to induce endometriosis. Two weeks later all four groups were each randomly divided into two equal-sized subgroups, receiving either green fluorescent protein-expressing platelets or saline infusion. In experiment 2, 2 weeks after the surgical induction of endometriosis, the mice were randomly divided into two groups, one receiving a 2-week treatment with a recombinant P-selectin protein and the other, non-immune IgG, both by intraperitoneal injection. MAIN OUTCOME MEASURE(S): Lesion size, hotplate latency, and immunohistochemistry analysis of platelet aggregation, angiogenesis, transforming growth factor ß1, α-smooth muscle actin, collagen I, and the extent of macrophage infiltration in ectopic implants. The extent of fibrosis also was evaluated in experiment 2. RESULT(S): P-selectin deficiency significantly retarded the development of endometriosis in a mouse model of endometriosis. In addition, soluble P-selectin treatment markedly reduced the lesion size in mouse through decreased platelet aggregation and angiogenesis, improved general hyperalgesia, and reduced the extent of macrophages infiltration, resulting in reduced fibrotic tissue content. CONCLUSION(S): Targeting P-selectin-mediated platelet adhesion onto endometriotic lesions holds promise as a novel therapeutics for treating endometriosis.

Andrographolide suppress tumor growth by inhibiting TLR4/NF-κB signaling activation in insulinoma.

Insulinomas are rare tumors, and approximately 10% of insulinomas are malignant. Accumulating evidence has implicated that we still lack effective therapy to treat the patients who are diagnosed with rare malignant insulinoma. Previous studies have reported that Andrographolide (Andro) could inhibit cell cycle progression, reduce cell invasion and induce cell apoptosis in many common cancer cells. However, the effects of andro are cell type-dependent. So we emplored the ß-TC-6 cells and the RIP1-Tag2 transgenic mouse model of endogenously growing insulinoma model to elucidate the possible anti-cancer effect of Andro on insulinoma, an uncommon type of malignant cancers in this study. Our experiments revealed that Andro significantly inhibited tumor growth at both the early-stage and the advanced-stage of insulinoma through targeting the TLR4/NF-κB signaling pathway. This work initially provides the evidence that the TLR4/NF-κB signaling pathway might be vital as a potential therapeutic target, and also indispensable in Andro-mediated anti-cancer effect in insulinoma.

Mst1/Mst2 regulate development and function of regulatory T cells through modulation of Foxo1/Foxo3 stability in autoimmune disease.

Foxp3 expression and regulatory T cell (Treg) development are critical for maintaining dominant tolerance and preventing autoimmune diseases. Human MST1 deficiency causes a novel primary immunodeficiency syndrome accompanied by autoimmune manifestations. However, the mechanism by which Mst1 controls immune regulation is unknown. In this article, we report that Mst1 regulates Foxp3 expression and Treg development/function and inhibits autoimmunity through modulating Foxo1 and Foxo3 (Foxo1/3) stability. We have found that Mst1 deficiency impairs Foxp3 expression and Treg development and function in mice. Mechanistic studies reveal that Mst1 enhances Foxo1/3 stability directly by phosphorylating Foxo1/3 and indirectly by attenuating TCR-induced Akt activation in peripheral T cells. Our studies have also shown that Mst1 deficiency does not affect Foxo1/3 cellular localization in CD4 T cells. In addition, we show that Mst1(-/-) mice are prone to autoimmune disease, and mutant phenotypes, such as overactivation of naive T cells, splenomegaly, and autoimmune pathological changes, are suppressed in Mst1(-/-) bone marrow chimera by cotransplanted wt Tregs. Finally, we demonstrate that Mst1 and Mst2 play a partially redundant role in Treg development and autoimmunity. Our findings not only identify Mst kinases as the long-searched-for factors that simultaneously activate Foxo1/3 and inhibit TCR-stimulated Akt downstream of TCR signaling to promote Foxp3 expression and Treg development, but also shed new light on understanding and designing better therapeutic strategies for MST1 deficiency-mediated human immunodeficiency syndrome.

Tongxinluo ameliorates renal structure and function by regulating miR-21-induced epithelial-to-mesenchymal transition in diabetic nephropathy.

Diabetic nephropathy (DN) is one of the most important diabetic microangiopathies. The epithelial-to-mesenchymal transition (EMT) plays an important role in DN. The physiological role of microRNA-21 (miR-21) was closely linked to EMT. However, it remained elusive whether tongxinluo (TXL) ameliorated renal structure and function by regulating miR-21-induced EMT in DN. This study aimed to determine the effect of TXL on miR-21-induced renal tubular EMT and to explore the relationship between miR-21 and TGF-ß1/smads signals. Real-time RT-PCR, cell transfection, in situ hybridization (ISH), and laser confocal microscopy were used, respectively. Here, we revealed that TXL dose dependently lowered miR-21 expression in tissue, serum, and cells. Overexpression of miR-21 can enhance α-smooth muscle actin (SMA) expression and decrease E-cadherin expression by upregulating smad3/p-smad3 expression and downregulating smad7 expression. Interestingly, TXL also increased E-cadherin expression and decreased α-SMA expression by regulating miR-21 expression. More importantly, TXL decreased collagen IV, fibronectin, glomerular basement membrane, glomerular area, and the albumin/creatinine ratio, whereas it increased the creatinine clearance ratio. The results demonstrated that TXL ameliorated renal structure and function by regulating miR-21-induced EMT, which was one of the mechanisms to protect against DN, and that miR-21 may be one of the therapeutic targets for TXL in DN.

Induction of intestinal stem cells by R-spondin 1 and Slit2 augments chemoradioprotection.

Cancer research has been rightly and successfully focused on prevention, early detection, and identification of specific molecular targets that distinguish the malignant cells from the neighbouring benign cells. However, reducing lethal tissue injury caused by intensive chemoradiotherapy during treatment of late-stage metastatic cancers remains a key clinical challenge. Here we tested whether the induction of adult stem cells could repair chemoradiation-induced tissue injury and prolong overall survival in mice. We found that intestinal stem cells (ISCs) expressed Slit2 and its single-span transmembrane cell-surface receptor roundabout 1 (Robo1). Partial genetic deletion of Robo1 decreased ISC numbers and caused villus hypotrophy, whereas a Slit2 transgene increased ISC numbers and triggered villus hypertrophy. During lethal dosages of chemoradiation, administering a short pulse of R-spondin 1 (Rspo1; a Wnt agonist) plus Slit2 reduced ISC loss, mitigated gut impairment and protected animals from death, without concomitantly decreasing tumour sensitivity to chemotherapy. Therefore Rspo1 and Slit2 may act as therapeutic adjuvants to enhance host tolerance to aggressive chemoradiotherapy for eradicating metastatic cancers.

Slit/Robo1 signaling regulates neural tube development by balancing neuroepithelial cell proliferation and differentiation.

Formation of the neural tube is the morphological hallmark for development of the embryonic central nervous system (CNS). Therefore, neural tube development is a crucial step in the neurulation process. Slit/Robo signaling was initially identified as a chemo-repellent that regulated axon growth cone elongation, but its role in controlling neural tube development is currently unknown. To address this issue, we investigated Slit/Robo1 signaling in the development of chick neCollege of Life Sciences Biocentre, University of Dundee, Dundee DD1 5EH, UKural tube and transgenic mice over-expressing Slit2. We disrupted Slit/Robo1 signaling by injecting R5 monoclonal antibodies into HH10 neural tubes to block the Robo1 receptor. This inhibited the normal development of the ventral body curvature and caused the spinal cord to curl up into a S-shape. Next, Slit/Robo1 signaling on one half-side of the chick embryo neural tube was disturbed by electroporation in ovo. We found that the morphology of the neural tube was dramatically abnormal after we interfered with Slit/Robo1 signaling. Furthermore, we established that silencing Robo1 inhibited cell proliferation while over-expressing Robo1 enhanced cell proliferation. We also investigated the effects of altering Slit/Robo1 expression on Sonic Hedgehog (Shh) and Pax7 expression in the developing neural tube. We demonstrated that over-expressing Robo1 down-regulated Shh expression in the ventral neural tube and resulted in the production of fewer HNK-1(+) migrating neural crest cells (NCCs). In addition, Robo1 over-expression enhanced Pax7 expression in the dorsal neural tube and increased the number of Slug(+) pre-migratory NCCs. Conversely, silencing Robo1 expression resulted in an enhanced Shh expression and more HNK-1(+) migrating NCCs but reduced Pax7 expression and fewer Slug(+) pre-migratory NCCs were observed. In conclusion, we propose that Slit/Robo1 signaling is involved in regulating neural tube development by tightly coordinating cell proliferation and differentiation during neurulation.

Retention of stem cell plasticity in avian primitive streak cells and the effects of local microenvironment.

Primitive streak (PS) is the first structure occurring in embryonic gastrulation, in which the epiblast cells undergo the epithelial-mesenchymal transition to become the loose mesoderm cells subsequently. Because the mesoderm cells departing from different portions of PS are blessed with disparate migration trajectory and differentiation fate, one question is when the cell fate is determinated. To understand whether the cell fate and cell migration pattern will be alternated along with the microenvironment transformation, the traditional transplantation technology was used to replace the anterior PS cells in HH4 host embryo using posterior PS tissue labeled by green fluorescent protein (GFP) in the same stage donor embryo, and then, we tracked the migration trajectory of the GFP-positive cells with fluorescence stereomicroscope after incubation, and eventually verified the cell contribution from the transplants with in situ hybridization and immunocytochemistry. The same experimental strategy applied for posterior PS site replacement in host embryo. We found that the transplanted posterior PS cells to anterior part of streak followed the anterior PS cell migration pattern rather than kept its posterior streak cell migration trajectory, and so did vice versa. In addition, the transplants were involved in the contribution to the subsequent organogenesis as the local PS tissues affirmed by specific expression of myocardial or hematopoietic markers. Therefore, our data strongly suggest that the PS cells still keep stem cell plasticity during gastrulation and the eventual cell fate will depend on the spatial gene expression within local microenvironment along with development.

Slit2 overexpression results in increased microvessel density and lesion size in mice with induced endometriosis.

We recently reported that Slit/Roundabout (ROBO) 1 pathway may be a constituent biomarker for recurrence of endometriosis, likely through promoting angiogenesis. In this study, we sought to determine as whether Slit2 overexpression can facilitate angiogenesis, increase lesion size, and induce hyperalgesia in mice with induced endometriosis. We used 30 Slit2 transgenic (S) and 29 wild-type (W) mice and cross-transplanted endometrial fragments from S to W (group SW) and vice versa (group WS), and also within the S and W (groups SS and WW, respectively), into the peritoneal cavity, inducing endometriosis. We also performed a sham surgery within both S and W mice (groups Sm and Wm, respectively). The size of the ectopic implants, microvessel density (MVD) and immunoreactivity to ROBO1, and vascular endothelial cell growth factor (VEGF) in ectopic and eutopic endometrium, along with hotplate and tail-flick tests in all mice, were then evaluated. We found that the induction of endometriosis resulted in generalized hyperalgesia, which was unaffected by Slit2 overexpression. Slit2 overexpression did increase the lesion size significantly and correlated positively with the MVD in ectopic and eutopic endometrium. Slit2 expression levels appear to correlate with the MVD, but not with VEGF immunoreactivity, in ectopic endometrium. Consequently, we conclude that Slit2 may play an important role in angiogenesis in endometriosis. The increased angiogenesis, as measured by MVD, but not VEGF immunoreactivity, likely resulted in increased lesion size in induced endometriosis. Thus, SLIT2/ROBO1 pathway may be a potential therapeutic target for treating endometriosis.

Plant lectin can target receptors containing sialic acid, exemplified by podoplanin, to inhibit transformed cell growth and migration.

Cancer is a leading cause of death of men and women worldwide. Tumor cell motility contributes to metastatic invasion that causes the vast majority of cancer deaths. Extracellular receptors modified by α2,3-sialic acids that promote this motility can serve as ideal chemotherapeutic targets. For example, the extracellular domain of the mucin receptor podoplanin (PDPN) is highly O-glycosylated with α2,3-sialic acid linked to galactose. PDPN is activated by endogenous ligands to induce tumor cell motility and metastasis. Dietary lectins that target proteins containing α2,3-sialic acid inhibit tumor cell growth. However, anti-cancer lectins that have been examined thus far target receptors that have not been identified. We report here that a lectin from the seeds of Maackia amurensis (MASL) with affinity for O-linked carbohydrate chains containing sialic acid targets PDPN to inhibit transformed cell growth and motility at nanomolar concentrations. Interestingly, the biological activity of this lectin survives gastrointestinal proteolysis and enters the cardiovascular system to inhibit melanoma cell growth, migration, and tumorigenesis. These studies demonstrate how lectins may be used to help develop dietary agents that target specific receptors to combat malignant cell growth.

SAP suppresses the development of experimental autoimmune encephalomyelitis in C57BL/6 mice.

Experimental autoimmune encephalomyelitis (EAE) is a CD4(+) T cell-mediated disease of the central nervous system. Serum amyloid P component (SAP) is a highly conserved plasma protein named for its universal presence in amyloid deposits. Here we report that SAP-transgenic mice had unexpectedly attenuated EAE due to impaired encephalitogenic responses. Following induction with myelin oligodendroglial glycoprotein (MOG) peptide 35-55 in complete Freund's adjuvant, SAP-transgenic mice showed reduced spinal cord inflammation with lower severity of EAE attacks as compared with control C57BL/6 mice. However, in SAP-Knockout mice, the severity of EAE is enhanced. Adoptive transfer of Ag-restimulated T cells from wild type to SAP-transgenic mice, or transfer of SAP-transgenic Ag-restimulated T cells to control mice, induced milder EAE. T cells from MOG-primed SAP-transgenic mice showed weak proliferative responses. Furthermore, in SAP-transgenic mice, there is little infiltration of CD45-positive cells in the spinal cord. In vitro, SAP suppressed the secretion of interleukin-2 stimulated by P-selectin and blocked P-selectin binding to T cells. Moreover, SAP could change the affinity between α4-integrin and T cells. These data suggested that SAP could antagonize the development of the acute phase of inflammation accompanying EAE by modulating the function of P-selectin.

Over-expression of Slit2 induces vessel formation and changes blood vessel permeability in mouse brain.

AIM: To investigate the effect of the axon guidance cue Slit2 on the density of blood vessels and permeability of the blood-brain barrier in mouse brain. METHODS: hSlit2 transgenic mouse line was constructed, and the phenotypes of the mice were compared with wild-type mice in respect to the lateral ventricle (LV), ventricle pressure, and the choroids plexus. An in vivo Miles permeability assay and an amyloid-ß permeability assay were used to assess the permeability of brain blood vessels. Brain vessel casting and intracerebral hemorrhage models were built to investigate vessel density in the transgenic mice. An in vitro permeability assay was used to test whether Slit2 could change the permeability and tight junctions of blood vessel endothelial cells. RESULTS: Hydrocephalus occurred in some transgenic mice, and a significantly larger lateral ventricle area and significantly higher ventricle pressure were observed in the transgenic mice. The transgenic mice displayed changed construction of the choroids plexus, which had more micro vessels, dilated vessels, gaps between epithelial cells and endothelial cells than wild-type mice. Slit2 significantly increased brain vessel density and the permeability of brain vessels to large molecules. These blood vessels were more sensitive to cues that induce brain hemorrhage. At the cellular level, Slit2 disturbed the integrity of tight junctions in blood vessel endothelial cells and improved the permeability of the endothelial cell layer. Thus, it promoted the entry of amyloid-ß peptides from the serum into the central nervous system, where they bound to neurons. CONCLUSION: Slit2 increases vessel density and permeability in the brains of transgenic mice. Thus, Slit2 induces numerous changes in brain vessels and the barrier system.

SH3KBP1-binding protein 1 prevents epidermal growth factor receptor degradation by the interruption of c-Cbl-CIN85 complex.

The binding of Cbl-interacting protein of 85 kDa (CIN85) to c-Cbl is important to endocytosis and degradation of epidermal growth factor receptor (EGFR). The proline-arginine motif PXXXPR in c-Cbl and SH3 domains of CIN85 are essential to this interaction. Here, we demonstrated that SH3KBP1-binding protein 1 (SHKBP1), which also contains two PXXXPR motifs, constitutively bound to SH3 domains of CIN85. Importantly, the binding of SHKBP1 prevented the interaction of CIN85 with c-Cbl and inhibited the translocation of CIN85 to EGFR-containing vesicles, thus reducing EGFR degradation and enhancing EGF-induced serum response element transcription activity. Therefore, our results indicated that SHKBP1 could promote EGFR signaling pathway by interrupting c-Cbl-CIN85 complex and inhibiting EGFR degradation.

[PTEN impedes EMT during chick embryo gastrulation].

PTEN has been considered as one of the important anti-oncogenes, which possesses very wide biological activities. Endogenous PTEN genes begin to express in epiblast during chick embryo gastrulation, and then the expression extends to neural plate and mesoderm. This suggests that PTEN might be involved in cell migration, proliferation, and differentiation during early embryo development. In this study, we employed in vivo approach to explore if endogenous PTEN participates in EMT (Epithelial-mesenchymal transition) in early chick embryo. PTEN was initially detected to highly express in primitive streak during chick gastrulation, in which EMT occurs, and subsequently mesoderm structure such as somites etc. Then, overexpression of both Wt PTEN-GFP and Wt PTEN-GFP positive transplantation of primitive streak resulted in cell accumulation in primitive streak in the development hereafter, indicating that EMT was blocked in both of our assays, either whole embryo transfection of Wt PTEN-GFP or transplantation of Wt PTEN-GFP primary streak tissue. Finally down-regulation of PTEN gene in one side using PTEN siRNA led to reduce the more number of mesoderm cells in PTNE siRNA side than normal side, which suggests that PTEN gene is probably involved in regulating EMT process in development of early embryonic gastrulation.

Slit-Robo signaling induces malignant transformation through Hakai-mediated E-cadherin degradation during colorectal epithelial cell carcinogenesis.

The Slit family of guidance cues binds to Roundabout (Robo) receptors and modulates cell migration. We report here that ectopic expression of Slit2 and Robo1 or recombinant Slit2 treatment of Robo1-expressing colorectal epithelial carcinoma cells recruited an ubiquitin ligase Hakai for E-cadherin (E-cad) ubiquitination and lysosomal degradation, epithelial-mesenchymal transition (EMT), and tumor growth and liver metastasis, which were rescued by knockdown of Hakai. In contrast, knockdown of endogenous Robo1 or specific blockade of Slit2 binding to Robo1 prevented E-cad degradation and reversed EMT, resulting in diminished tumor growth and liver metastasis. Ectopic expression of Robo1 also triggered a malignant transformation in Slit2-positive human embryonic kidney 293 cells. Importantly, the expression of Slit2 and Robo1 was significantly associated with an increased metastatic risk and poorer overall survival in colorectal carcinoma patients. We conclude that engagement of Robo1 by Slit2 induces malignant transformation through Hakai-mediated E-cad ubiquitination and lysosomal degradation during colorectal epithelial cell carcinogenesis.

The role of nuclear factor-kappa-B p50 subunit in the development of endometriosis.

p50 is a member of the NF-kappaB family known to be involved in endometriosis. To gain insight into the roles of p50 in the development of endometriosis, we cross-transplanted endometrial fragments from p50 knockout mice to wild-type mice and vice versa, and also autotransplanted the fragments within the knockout and wild-type mice, inducing endometriosis. We then evaluated the size of the endometrial implants, and immunoreactivity to phosphorylated p65 (p-p65), PKCepsilon and TRPV1 in ectopic and eutopic endometrium as well as in vagina. We found that p50 deletion significantly reduces the size of endometrial implants. The immunoreactivity to p-p65 and PKCepsilon, but not TRPV1, was reduced in endometrial implants in p50 knockout mice. Deletion of p50 significantly reduced p-p65 and PKCepsilon, but not TRPV1, expression in eutopic endometrium and vagina. It also disrupts NF-kappaB activation and PKCepsilon expression in eutopic and vagina, suggesting the role of NF-kappaB in regulating PKCepsilon, which plays an important role in nociception. These data show that p50 is involved in the development of endometriosis and may be a promising therapeutic target.

Increased immunoreactivity to SLIT/ROBO1 and its correlation with severity of dysmenorrhea in adenomyosis.

Compared with normal endometrium, SLIT expression was statistically significantly higher in ectopic endometrium from women with adenomyosis, while roundabout 1 (ROBO1) immunoreactivity and microvessel density (MVD) level were statistically significantly higher in both eutopic and ectopic endometrium than normal endometrium. Both SLIT immunoreactivity in ectopic endometrium and MVD in eutopic endometrium were positively correlated with the severity of dysmenorrhea and found to be significant predicators for dysmenorrhea severity in women with adenomyosis.

Slit-2 repels the migration of olfactory ensheathing cells by triggering Ca2+-dependent cofilin activation and RhoA inhibition.

Olfactory ensheathing cells (OECs) migrate from the olfactory epithelium towards the olfactory bulb during development. However, the guidance mechanism for OEC migration remains a mystery. Here we show that migrating OECs expressed the receptor of the repulsive guidance factor Slit-2. A gradient of Slit-2 in front of cultured OECs first caused the collapse of the leading front, then the reversal of cell migration. These Slit-2 effects depended on the Ca(2+) release from internal stores through inositol (1,4,5)-triphosphate receptor channels. Interestingly, in response to Slit-2 stimulation, collapse of the leading front required the activation of the F-actin severing protein cofilin in a Ca(2+)-dependent manner, whereas the subsequent reversal of the soma migration depended on the reversal of RhoA activity across the cell. Finally, the Slit-2-induced repulsion of cell migration was fully mimicked by co-application of inhibitors of F-actin polymerization and RhoA kinase. Our findings revealed Slit-2 as a repulsive guidance factor for OEC migration and an unexpected link between Ca(2+) and cofilin signaling during Slit-2-triggered repulsion.