Bone Morphogenetic Protein Receptor Research Articles

O8G Site-Specifically Modified tRF-1-AspGTC: A Novel Therapeutic Target and Biomarker for Pulmonary Hypertension.

Hypoxia and oxidative stress contribute to the development of pulmonary hypertension (PH). tRNA-derived fragments play important roles in RNA interference and cell proliferation, but their epitranscriptional roles in PH development have not been investigated. We aimed to gain insight into the mechanistic contribution of oxidative stress-induced 8-oxoguanine in pulmonary vascular remodeling. Through small RNA modification array analysis and quantitative polymerase chain reaction, a significant upregulation of the 8-oxoguanine-modified tRF-1-AspGTC was found in the lung tissues and the serum of patients with PH. This modification occurs at the fifth 8-oxoguanine (5o8G) tRF in the seed region of the tRNA-derived fragments. Inhibition of the 5o8G tRF reversed hypoxia-induced proliferation and apoptosis resistance in pulmonary artery smooth muscle cells. Further investigation unveiled that the 5o8G tRF retargeted mRNA of WNT5A and CASP3 and inhibited their expression. Ultimately, BMPR2 (bone morphogenetic protein receptor 2)-reactive oxygen species/5o8G tRF/WNT5A signaling pathway exacerbated the progression of PH. Our study highlights the role of site-specific 8-oxoguanine-modified tRF in promoting the development of PH. Our findings present a promising therapeutic avenue for managing PH and propose 5o8G tRF as a potential innovative marker for diagnosing this disease.

Blood flow regulates acvrl1 transcription via ligand-dependent Alk1 activity.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant disease characterized by the development of arteriovenous malformations (AVMs) that can result in significant morbidity and mortality. HHT is caused primarily by mutations in bone morphogenetic protein receptors ACVRL1/ALK1, a signaling receptor, or endoglin (ENG), an accessory receptor. Because overexpression of Acvrl1 prevents AVM development in both Acvrl1 and Eng null mice, enhancing ACVRL1 expression may be a promising approach to development of targeted therapies for HHT. Therefore, we sought to understand the molecular mechanism of ACVRL1 regulation. We previously demonstrated in zebrafish embryos that acvrl1 is predominantly expressed in arterial endothelial cells and that expression requires blood flow. Here, we document that flow dependence exhibits regional heterogeneity and that acvrl1 expression is rapidly restored after reinitiation of flow. Furthermore, we find that acvrl1 expression is significantly decreased in mutants that lack the circulating Alk1 ligand, Bmp10, and that, in the absence of flow, intravascular injection of BMP10 or the related ligand, BMP9, restores acvrl1 expression in an Alk1-dependent manner. Using a transgenic acvrl1:egfp reporter line, we find that flow and Bmp10 regulate acvrl1 at the level of transcription. Finally, we observe similar ALK1 ligand-dependent increases in ACVRL1 in human endothelial cells subjected to shear stress. These data suggest that ligand-dependent Alk1 activity acts downstream of blood flow to maintain or enhance acvrl1 expression via a positive feedback mechanism, and that ALK1 activating therapeutics may have dual functionality by increasing both ALK1 signaling flux and ACVRL1 expression.

MiR-143-3p regulates chondrogenic differentiation of synovium derived mesenchymal stem cells under mechanical stress through the BMPR2-Smad signalling pathway by targeting BMPR2.

Mesenchymal stem cells (MSCs) derived from the synovium, known as synovium mesenchymal stem cells (SMSCs), exhibit significant potential for articular cartilage regeneration owing to their capacity for chondrogenic differentiation. However, the microRNAs (miRNAs) governing this process and the associated mechanisms remain unclear. While mechanical stress positively influences chondrogenesis in MSCs, the miRNA-mediated response of SMSCs to mechanical stimuli is not well understood. This study explores the miRNA-driven mechano-transduction in SMSCs chondrogenesis under mechanical stress. The surface phenotype of SMSCs was analysed by flow cytometry. Chondrogenesis capacities of SMSCs were examined by Alcian blue staining. High throughput sequencing was used to screen mechano-sensitive miRNAs of SMSCs. The RNA expression level of COL2A1, ACAN, SOX9, BMPR2 and miR-143-3p of SMSCs were tested by quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between miR-143-3p and TLR4 was confirmed by luciferase reporter assays. The protein expression levels of related genes were assessed by western blot. High-throughput sequencing revealed a notable reduction in miR-143-3p levels in mechanically stressed SMSCs. Gain- or loss-of-function strategies introduced by lentivirus demonstrated that miR-143-3p overexpression hindered chondrogenic differentiation, whereas its knockdown promoted this process. Bioinformatics scrutiny and luciferase reporter assays pinpointed a potential binding site for miR-143-3p within the 3'-UTR of bone morphogenetic protein receptor type 2 (BMPR2). MiR-143-3p overexpression decreased BMPR2 expression and phosphorylated Smad1, 5 and 8 levels, while its inhibition activated BMPR2-Smad pathway. This study elucidated that miR-143-3p negatively regulates SMSCs chondrogenic differentiation through the BMPR2-Smad pathway under mechanical tensile stress. The direct targeting of BMPR2 by miR-143-3p established a novel dimension to our understanding of mechano-transduction mechanism during SMSC chondrogenesis. This understanding is crucial for advancing strategies in articular cartilage regeneration.

Ethanol-induced lung and cardiac right ventricular inflammation and remodeling underlie progression to pulmonary arterial hypertension.

Current research on ethanol-induced cardiovascular anomalies has focused on left ventricular (LV) function and blood pressure. To extend this area of research, we sought to determine whether ethanol-induced alterations in the structure and function of the right cardiac ventricle (RV) and pulmonary artery (PA) lead to pulmonary arterial hypertension (PAH). Two groups of male Sprague-Dawley rats received a balanced liquid diet containing 5% ethanol (w/v) or a pair-fed isocaloric liquid diet for 8 weeks. Weekly echocardiography was conducted to evaluate cardiopulmonary function, and lung and RV tissues were collected for exvivo histological and molecular studies. The ethanol-treated rats exhibited: (1) Elevated mean pulmonary arterial pressure and decreased pulmonary artery acceleration time/ejection time; (2) Pulmonary vascular remodeling comprising intrapulmonary artery medial layer thickening; and (3) RV hypertrophy along with increased RV/LV + septum, RV diameter, RV cardiomyocyte cross-sectional area, and LV mass/body weight ratio. These responses were associated with increased lung and RV pro-inflammatory markers, endothelin-1 (ET-1), TNF-α, and IL-6 levels and higher ET-1,ET-1 type A/B receptor ratio, and downregulation of the cytoprotective protein, bone morphogenetic protein receptor 2 (BMPR2), in the lungs. These findings show that moderate ethanol-induced cardiopulmonary changes underlie progression to PAH via an upregulated proinflammatory ET1-TNFα-IL6 pathway and suppression of the anti-inflammatory BMPR2.

Capitella teleta gets left out: possible evolutionary shift causes loss of left tissues rather than increased neural tissue from dominant-negative BMPR1

BackgroundThe evolution of central nervous systems (CNSs) is a fascinating and complex topic; further work is needed to understand the genetic and developmental homology between organisms with a CNS. Research into a limited number of species suggests that CNSs may be homologous across Bilateria. This hypothesis is based in part on similar functions of BMP signaling in establishing fates along the dorsal-ventral (D-V) axis, including limiting neural specification to one ectodermal region. From an evolutionary-developmental perspective, the best way to understand a system is to explore it in a wide range of organisms to create a full picture.MethodsHere, we expand our understanding of BMP signaling in Spiralia, the third major clade of bilaterians, by examining phenotypes after expression of a dominant-negative BMP Receptor 1 and after knock-down of the putative BMP antagonist Chordin-like using CRISPR/Cas9 gene editing in the annelid Capitella teleta (Pleistoannelida).ResultsEctopic expression of the dominant-negative Ct-BMPR1 did not increase CNS tissue or alter overall D-V axis formation in the trunk. Instead, we observed a unique asymmetrical phenotype: a distinct loss of left tissues, including the left eye, brain, foregut, and trunk mesoderm. Adding ectopic BMP4 early during cleavage stages reversed the dominant-negative Ct-BMPR1 phenotype, leading to a similar loss or reduction of right tissues instead. Surprisingly, a similar asymmetrical loss of left tissues was evident from CRISPR knock-down of Ct-Chordin-like but concentrated in the trunk rather than the episphere.ConclusionsOur data highlight a novel asymmetrical phenotype, giving us further insight into the complicated story of BMP’s developmental role. We further solidify the hypothesis that the function of BMP signaling during the establishment of the D-V axis and CNS is fundamentally different in at least Pleistoannelida, possibly in Spiralia, and is not required for nervous system delimitation in this group.

Loss of tumor-derived SMAD4 enhances primary tumor growth but not metastasis following BMP4 signalling

BackgroundBone morphogenetic protein 4 (BMP4) is a potent inhibitor of breast cancer metastasis. However, a tumor-promoting effect of BMP4 is reported in other tumor types, especially when SMAD4 is inactive.MethodsTo assess the requirement for SMAD4 in BMP4-mediated suppression of metastasis, we knocked down SMAD4 in two different breast tumors and enforced SMAD4 expression in a third line with endogenous SMAD4 deletion. In addition, we assessed the requirement for SMAD4 in tumor cell-specific BMP signalling by expression of a constitutively active BMP receptor. Delineation of genes regulated by BMP4 in the presence or absence of SMAD4 was assessed by RNA sequencing and a BMP4-induced gene, MYO1F was assessed for its role in metastasis. Genes regulated by BMP4 and/or SMAD4 were assessed in a publicly available database of gene expression profiles of breast cancer patients.ResultsIn the absence of SMAD4, BMP4 promotes primary tumor growth that is accompanied by increased expression of genes associated with DNA replication, cell cycle, and MYC signalling pathways. Despite increased primary tumor growth, BMP4 suppresses metastasis in the absence of tumor cell expression of SMAD4. Consistent with the anti-metastatic activity of BMP4, enforced signalling through the constitutively active receptor in SMAD4 positive tumors that lacked BMP4 expression still suppressed metastasis, but in the absence of SMAD4, the suppression of metastasis was largely prevented. Thus BMP4 is required for suppression of metastasis regardless of tumor SMAD4 status. The BMP4 upregulated gene, MYO1F, was shown to be a potent suppressor of breast cancer metastasis. Gene signature upregulated by BMP4 in the absence of SMAD4 was associated with poor prognosis in breast cancer patients, whereas gene signature upregulated by BMP4 in the presence of SMAD4 was associated with improved prognosis.ConclusionsBMP4 expression is required for suppression of metastasis regardless of the SMAD4 status of the tumor cells. Since BMP4 is a secreted protein, we conclude that it can act both in an autocrine manner in SMAD4-expressing tumor cells and in a paracrine manner on stromal cells to suppress metastasis. Deletion of SMAD4 from tumor cells does not prevent BMP4 from suppressing metastasis via a paracrine mechanism.

Mechanistic Insights into Nonylphenol Stress on BMP2 and BMP4 Gene Expression in Red Crucian Carp (Carassius auratus Red var.)

Nonylphenol (NP) is a known endocrine-disrupting chemical (EDC) that has been shown to affect bone development in mammals. However, the detrimental impacts of NP on the skeletal growth and development of aquatic species, especially bony fish, remain poorly understood. Bone morphogenic proteins (BMPs), essential for bone formation and osteoblast differentiation, act through the BMP-Smad signaling pathway. In this study, two BMP genes, BMP2 and BMP4, were cloned and characterized in the red crucian carp (Carassius auratus red var.). The full-length cDNAs of BMP2 and BMP4 were 2029 bp and 2095 bp, respectively, encoding polypeptides of 411 and 433 amino acids, and share a typical TGF-β domain with other BMPs. The tissue expression patterns of both genes were identified, showing ubiquitous expression across all studied tissues. Additionally, the exposure of embryos or adult fish to NP stress resulted in a downregulation of BMP2, BMP4, and other genes associated with the BMP-Smad signaling pathway. Moreover, the combined treatment of adult fish with NP and the specific BMP receptor inhibitor significantly reduced these genes’ expression. These findings elucidate the mechanism of NP stress on BMP2 and BMP4, suggesting a role for the BMP-Smad signaling pathway in the response to endocrine-disrupting chemicals in fish.

Epithelial-mesenchymal interaction protects normal colonocytes from 4-HNE-induced phenotypic transformation.

Recent studies have shown that epithelial-stromal interactions could play a role in the development of colorectal cancer. Here, we investigated the role of fibroblasts in the transformation of normal colonocytes induced by 4-HNE. Normal Co colonocytes and nF fibroblasts from the same mouse colon were exposed, in monoculture (m) or coculture (c), to 4-HNE (5 μM) twice weekly for 3 weeks. Gene expression was then analysed and the ability of Co colonocytes to grow in anchorage-independent conditions was tested in soft agar. Fibroblasts previously treated or not with 4-HNE were also seeded in culture inserts positioned above the agar layers to allow paracrine exchanges with colonocytes. First, 60% of the genes studied were modulated by coculture in Co colonocytes, with notably increased expression of BMP receptors. Furthermore, while 4-HNE increased the ability of monoculture-treated Co colonocytes to form colonies, this effect was not observed in coculture-treated Co colonocytes. Adding a selective BMPR1 inhibitor during the treatment phase abolished the protective effect of coculture. Conversely, addition of a BMP4 agonist to the medium of monoculture-treated Co colonocytes prevented phenotypic transformation by 4-HNE. Second, the presence of nF(m)-HNE fibroblasts during the soft agar assay increased the number and size of Co(m) colonocyte colonies, regardless of whether these cells had been previously treated with 4-HNE in monoculture. For soft agar assays performed with nF(c) and Co(c) cells initially treated in coculture, only the reassociation between Co(c)-HNE and nF(c)-HNE resulted in a small increase in the number of colonies. During the exposure phase, the epithelial-mesenchymal interaction protected colonocytes from 4-HNE-induced phenotypic transformation via activation of the BMP pathway. This intercellular dialogue also limited the ability of fibroblasts to subsequently promote colonocyte-anchorage-independent growth. In contrast, fibroblasts pre-exposed to 4-HNE in monoculture strongly increased the ability of Co(m) colonocytes to form colonies.

Association of polymorphism in the promotor area of the caprine BMPR1B gene with litter size and body measurement traits in Damani goats.

This study aimed to explore polymorphisms in the promoter region of the caprine BMPR1B (Bone morphogenetic protein receptor 1 beta) gene and its association with body measurement and litter size traits in Damani does. A total of 53 blood samples were collected to analyze the association between the BMPR1B gene polymorphism and 11 phenotypic traits in Damani female goats. The results revealed that three novel SNPs were identified in the promoter region of the caprine BMPR1B gene, including g.67 A > C (SNP1), g.170 G > A(SNP2), and g.501A > T (SNP3), among which the SNP1 and SNP2 were significantly (p < 0.05) associated with litter size and body measurement traits in Damani goats. In SNP1 the AC genotype could be used as a marker for litter size, and the CC genotype for body weight in Damani goats. In SNP2, the genotype GG was significantly (p < 0.05) associated with ear and head length. Therefore, we can conclude from the present study, that genetic variants AC and CC of the caprine BMPR1B gene could be used as genetic markers for economic traits through marker-assisted selection for the breed improvement program of the Damani goat.

Effects of the ferroptosis inducer erastin on osteogenic differentiation and biological pathways of primary osteoblasts

ABSTRACT Background Periodontitis is a chronic destructive inflammatory disease exacerbated by osteoblast dysfunction. Ferroptosis has emerged as a significant factor that could contribute to the pathological changes observed in periodontitis. However, the impact of ferroptosis on osteogenic differentiation and gene expression patterns of primary osteoblasts remain elusive. Methods In this study, osteoblasts were osteogenically induced for specific durations with and without the ferroptosis inducer erastin. Subsequently, cell proliferation, ferroptosis-related molecules, and osteogenic differentiation capacity were assessed. Furthermore, the differences in transcriptome expression following erastin treatment were analyzed by RNA sequencing. Results The results demonstrated that erastin treatment induced ferroptosis, resulting in suppressed cell proliferation and impaired osteogenic differentiation. Transcriptomic analysis revealed significant alterations in processes such as hydrogen peroxide catabolism, response to lipid peroxidation, and metal iron binding, as well as BMP receptor activity and collagen type XI trimer. Conclusion The ferroptosis inducer erastin inhibited osteoblast proliferation and differentiation. Our study provides novel insights into the effect of ferroptosis on osteogenesis, suggesting that targeting ferroptosis may present a promising approach in the treatment of periodontitis.

Mesenchymal stromal cell chondrogenesis under ALK1/2/3-specific BMP inhibition: a revision of the prohypertrophic signalling network concept

BackgroundIn vitro chondrogenesis of mesenchymal stromal cells (MSCs) driven by the essential chondro-inducer transforming growth factor (TGF)-β is instable and yields undesired hypertrophic cartilage predisposed to bone formation in vivo. TGF-β can non-canonically activate bone morphogenetic protein-associated ALK1/2/3 receptors. These have been accused of driving hypertrophic MSC misdifferentiation, but data remained conflicting. We here tested the antihypertrophic capacity of two highly specific ALK1/2/3 inhibitors – compound A (CompA) and LDN-212854 (LDN21) – in order to reveal potential prohypertrophic contributions of these BMP/non-canonical TGF-β receptors during MSC in vitro chondrogenesis.MethodsStandard chondrogenic pellet cultures of human bone marrow-derived MSCs were treated with TGF-β and CompA (500 nM) or LDN21 (500 nM). Daily 6-hour pulses of parathyroid hormone-related peptide (PTHrP[1–34], 2.5 nM, from day 7) served as potent antihypertrophic control treatment. Day 28 samples were subcutaneously implanted into immunodeficient mice.ResultsAll groups underwent strong chondrogenesis, but GAG/DNA deposition and ACAN expression were slightly but significantly reduced by ALK inhibition compared to solvent controls along with a mild decrease of the hypertrophy markers IHH-, SPP1-mRNA, and Alkaline phosphatase (ALP) activity. When corrected for the degree of chondrogenesis (COL2A1 expression), only pulsed PTHrP but not ALK1/2/3 inhibition qualified as antihypertrophic treatment. In vivo, all subcutaneous cartilaginous implants mineralized within 8 weeks, but PTHrP pretreated samples formed less bone and attracted significantly less haematopoietic marrow than ALK1/2/3 inhibitor groups.ConclusionsOverall, our data show that BMP-ALK1/2/3 inhibition cannot program mesenchymal stromal cells toward stable chondrogenesis. BMP-ALK1/2/3 signalling is no driver of hypertrophic MSC misdifferentiation and BMP receptor induction is not an adverse prohypertrophic side effect of TGF-β that leads to endochondral MSC misdifferentiation. Instead, the prohypertrophic network comprises misregulated PTHrP/hedgehog signalling and WNT activity, and a potential contribution of TGF-β-ALK4/5-mediated SMAD1/5/9 signalling should be further investigated to decide about its postulated prohypertrophic activity. This will help to successfully engineer cartilage replacement tissues from MSCs in vitro and translate these into clinical cartilage regenerative therapies.

Coexistence of pulmonary arterial hypertension and straight back syndrome in a patient with a novel BMPR2 variant affecting cytoplasmic tail domain

BackgroundPathologic variants in the bone morphogenetic protein receptor-2 (BMPR2) gene cause a pulmonary arterial hypertension phenotype in an autosomal-dominant pattern with incomplete penetrance. Straight back syndrome is one of the causes of pseudo-heart diseases. To date, no cases of idiopathic or heritable pulmonary arterial hypertension with straight back syndrome have been reported.Case presentationA 30-year-old female was diagnosed with pulmonary arterial hypertension by right heart catheterization. Computed tomography revealed a decreased anteroposterior thoracic space with heart compression, indicating a straight back syndrome. Genetic analysis by whole exome sequencing identified a novel c.2423_2424delGT (p.G808Gfs*4) germline frameshift variant within BMPR2 affecting the cytoplasmic tail domain.ConclusionsThis is the first report of different straight back characteristics in heritable pulmonary arterial hypertension with a novel germline BMPR2 variant. This finding may provide a new perspective on the variable penetrance of the pulmonary arterial hypertension phenotype.

Royal Jelly Enhances the Ability of Myoblast C2C12 Cells to Differentiate into Multilineage Cells.

Royal jelly (RJ) is recognized as beneficial to mammalian health. Multilineage differentiation potential is an important property of mesenchymal stem cells (MSCs). C2C12 cells have an innate ability to differentiate into myogenic cells. Like MSCs, C2C12 cells can also differentiate into osteoblast- and adipocyte-lineage cells. We recently reported that RJ enhances the myogenic differentiation of C2C12 cells. However, the effect of RJ on osteoblast or adipocyte differentiation is still unknown. Here in this study, we have examined the effect of RJ on the osteoblast and adipocyte differentiation of C2C12 cells. Protease-treated RJ was used to reduce the adverse effects caused by RJ supplementation. To induce osteoblast or adipocyte differentiation, cells were treated with bone morphogenetic proteins (BMP) or peroxisome proliferator-activated receptor γ (PPARγ) agonist, respectively. RNA-seq was used to analyze the effect of RJ on gene expression. We found that RJ stimulates osteoblast and adipocyte differentiation. RJ regulated 279 genes. RJ treatment upregulated glutathione-related genes. Glutathione, the most abundant antioxidative factor in cells, has been shown to promote osteoblast differentiation in MSC and MSC-like cells. Therefore, RJ may promote osteogenesis, at least in part, through the antioxidant effects of glutathione. RJ enhances the differentiation ability of C2C12 cells into multiple lineages, including myoblasts, osteoblasts, and adipocytes.

B-cells in pulmonary arterial hypertension: friend, foe or bystander?

There is an unmet need for new therapeutic strategies that target alternative pathways to improve the prognosis of patients with pulmonary arterial hypertension (PAH). As immunity has been involved in the development and progression of vascular lesions in PAH, we review the potential contribution of B-cells in its pathogenesis and evaluate the relevance of B-cell-targeted therapies. Circulating B-cell homeostasis is altered in PAH patients, with total B-cell lymphopenia, abnormal subset distribution (expansion of naïve and antibody-secreting cells, reduction of memory B-cells) and chronic activation. B-cells are recruited to the lungs through local chemokine secretion, and activated by several mechanisms: 1) interaction with lung vascular autoantigens through cognate B-cell receptors; 2) costimulatory signals provided by T follicular helper cells (interleukin (IL)-21), type 2 T helper cells and mast cells (IL-4, IL-6 and IL-13); and 3) increased survival signals provided by B-cell activating factor pathways. This activity results in the formation of germinal centres within perivascular tertiary lymphoid organs and in the local production of pathogenic autoantibodies that target the pulmonary vasculature and vascular stabilisation factors (including angiotensin-II/endothelin-1 receptors and bone morphogenetic protein receptors). B-cells also mediate their effects through enhanced production of pro-inflammatory cytokines, reduced anti-inflammatory properties by regulatory B-cells, immunoglobulin (Ig)G-induced complement activation, and IgE-induced mast cell activation. Precision-medicine approaches targeting B-cell immunity are a promising direction for select PAH conditions, as suggested by the efficacy of anti-CD20 therapy in experimental models and a trial of rituximab in systemic sclerosis-associated PAH.

The role of immune cells and inflammation in pulmonary hypertension: mechanisms and implications.

Pulmonary hypertension (PH) is a malignant disease with progressive increase of pulmonary vascular pressure, which eventually leads to right heart failure. More and more evidences show that immune cells and inflammation play an important role in the occurrence and development of PH. In the context of pulmonary vascular diseases, immune cells migrate into the walls of the pulmonary vascular system. This leads to an increase in the levels of cytokines and chemokines in both the bloodstream and the surrounding tissues of the pulmonary vessels. As a result, new approaches such as immunotherapy and anti-inflammatory treatments are being considered as potential strategies to halt or potentially reverse the progression of PH. We reviewed the potential mechanisms of immune cells, cytokines and chemokines in PH development. The potential relationship of vascular cells or bone morphogenetic protein receptor 2 (BMPR2) in immune regulation was also expounded. The clinical application and future prospect of immunotherapy were further discussed.

Novel role of bone morphogenetic protein 9 in innate host responses to HCMV infection

Herpesviruses modulate immune control to secure lifelong infection. The mechanisms Human Cytomegalovirus (HCMV) employs in this regard can reveal unanticipated aspects of cellular signaling involved in antiviral immunity. Here, we describe a novel relationship between the TGF-β family cytokine BMP9 and HCMV infection. We identify a cross-talk between BMP9-induced and IFN receptor-mediated signaling, showing that BMP9 boosts the transcriptional response to and antiviral activity of IFNβ, thereby enhancing viral restriction. We also show that BMP9 is secreted by human fibroblasts upon HCMV infection. However, HCMV infection impairs BMP9-induced enhancement of the IFNβ response, indicating that this signaling role of BMP9 is actively targeted by HCMV. Indeed, transmembrane proteins US18 and US20, which downregulate type I BMP receptors, are necessary and sufficient to cause inhibition of BMP9-mediated boosting of the antiviral response to IFNβ. HCMV lacking US18 and US20 is more sensitive to IFNβ. Thus, HCMV has a mutually antagonistic relationship with BMP9, which extends the growing body of evidence that BMP signaling is an underappreciated modulator of innate immunity in response to viral infection.

Inhibition of BMP signaling pathway induced senescence and calcification in anaplastic meningioma

PurposeMeningiomas are the most common type of brain tumors and are generally benign, but malignant atypical meningiomas and anaplastic meningiomas frequently recur with poor prognosis. The metabolism of meningiomas is little known, so few effective treatment options other than surgery and radiation are available, and the targets for treatment of recurrence are not well defined. The Aim of this paper is to find the therapeutic target.MethodsThe effects of bone morphogenetic protein (BMP) signal inhibitor (K02288) and upstream regulator Gremlin2 (GREM2) on meningioma’s growth and senescence were examined. In brief, we examined as follows: 1) Proliferation assay by inhibiting BMP signaling. 2) Comprehensive analysis of forced expression GREM2.3) Correlation between GREM2 mRNA expression and proliferation marker in 87 of our clinical samples. 4) Enrichment analysis between GREM2 high/low expressed groups using RNA-seq data (42 cases) from the public database GREIN. 5) Changes in metabolites and senescence markers associated with BMP signal suppression.ResultsInhibitors of BMP receptor (BMPR1A) and forced expression of GREM2 shifted tryptophan metabolism from kynurenine/quinolinic acid production to serotonin production in malignant meningiomas, reduced NAD + /NADH production, decreased gene cluster expression involved in oxidative phosphorylation, and caused decrease in ATP. Finally, malignant meningiomas underwent cellular senescence, decreased proliferation, and eventually formed psammoma bodies. Reanalyzed RNA-seq data of clinical samples obtained from GREIN showed that increased expression of GREM2 decreased the expression of genes involved in oxidative phosphorylation, similar to our experimental results.ConclusionsThe GREM2-BMPR1A-tryptophan metabolic pathway in meningiomas is a potential new therapeutic target.

Detection of Booroola Polymorphism of Bone Morphogenetic Protein Receptor 1b and Embrapa Polymorphism of Growth Differentiation Factor 9 in Sheep in Thailand.

This study aimed to investigate the appearance and frequencies of the Booroola polymorphism of the bone morphogenetic protein receptor 1b (BMPR1B) gene (FecB) and the Embrapa polymorphism of the growth differentiation factor 9 (GDF9) gene (FecGE) in sheep in Thailand. A total of 454 crossbred sheep blood samples were collected from four provinces in Thailand during August 2022 to July 2023. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to identify the FecB and FecGE genotypes. The history of ewe birth types was collected from the owners to analyze the association between fecundity (Fec) genotypes and the history of birth types. The genotypic frequencies of FecB for homozygous genotype (B/B), heterozygous genotype (+/B), and wildtype (+/+) were 0.22%, 1.54%, and 98.24%, respectively. Meanwhile, the genotypic frequencies of FecGE for homozygous genotype (E/E), heterozygous genotype (+/E), and wildtype (+/+) were 0.00%, 2.42%, and 97.58%, respectively. Furthermore, three ewes exhibited both FecB and FecGE genotypes. Fisher's exact test revealed that possession of the FecB genotype was associated with multiple births (p < 0.01). Both FecB and FecGE mutations were identified in crossbred sheep in Thailand. Sheep containing FecB allele could be alternative candidates to be selected to improve the prolificacy of crossbred sheep in Thailand.

LncRNA S100PBP promotes proliferation and steroid hormone synthesis of granulosa cells by sponging MiR-2285bc-BMPR2 in bovine.

In bovine follicular development, the proliferation of bovine granulosa cells (GCs) affect follicular selection, atresia, and cystic follicle formation. With the proliferation of GCs and secretion of steroid hormones, follicles develop further and increase in diameter. However, when cystic follicles appear on the ovaries, GCs stop proliferating, resulting in the reduction of GCs layer. In our previous study, the whole transcriptome sequencing revealed that Bone morphogenetic protein receptor 2 (BMPR2) was differentially expressed (DE) between cystic and normal follicular GCs. We speculated that lncRNA may act as ceRNA targeting miRNAs and then regulating the expression of BMPR2 and the function of GCs, thereby affecting follicular development and cyst formation. In this study, the results elucidated that lncRNA S100PBP (NONBTAT011846.2) directly bound miR-2285bc, which targeted in the BMPR2 3'-UTR. miR-2285bc suppresses GCs proliferation by downregulating BMPR2 expression. Furthermore, lncRNA S100PBP was silenced by small interfering RNA (siRNA), and lncRNA S100PBP regulated BMPR2 expression by sponging miR-2285bc investigated through cross-verification. When siRNA of lncRNA S100PBP was transfected into GCs, the results revealed similar molecular changes as those transfected with miR-2285bc mimics. Silencing lncRNA S100PBP or overexpressing miR-2285bc altered the expressions of some follicular development-related genes, which could be related to follicular cyst occurrence. In conclusion, our findings support that lncRNA S100PBP regulates the expression of BMPR2 through sponge miR-2285bc, promotes the proliferation of GCs, inhibits their apoptosis, and increases the synthesis and secretion of follicular steroid hormones, thus promoting the development of bovine follicles and potentially inhibiting the formation of follicular cysts.

A3 INVESTIGATING MACROPHAGE-TISSUE CELL COMMUNICATION AXES IN THE GASTROINTESTINAL TRACT

Abstract Background The gastrointestinal tract boasts the highest concentration of macrophages (MPs) in the body, acting as vital immune sentinels that oversee tissue balance. Three distinct subsets of MPs, namely CCR2+, Tim4+, and CCR2,Tim4 double-negative (DN) MPs, populate distinct gut niches. Their functional specialization suggests unique interactions within their non-hematopoietic tissue microenvironments. Despite their crucial roles, the intricacies of these interactions remain elusive. One recently discovered interaction involves a communication axis between MPs and neurons within the muscularis layer of the gut. Here, neurons secrete Colony Stimulating Factor 1 (CSF1), a survival factor for MPs. These MPs reciprocate by producing Bone Morphogenetic Protein 2 (BMP2), assisting neurons in regulating gut motility. Aims Based on the aforementioned interaction, we hypothesize that BMP2, derived from tissue-resident MPs, might influence functions of other tissue niches, subsequently prompting survival of MP via CSF1 production. Our aims are twofold: (1) Identify the role of BMP2 in gut macrophages; (2) Identify BMP2-responsive CSF1-producing tissue cells within the gut. Methods To discern the roles of MP subsets, we developed a conditional knockout mouse model, targeting Bmp2 expression in MPs. We validated successful Bmp2 deletion(BMP2 KO) through quantitative polymerase chain reaction (qPCR) and an in-situ hybridization immunofluorescence assay (RNAscope). Subsequently, single cell RNA (scRNAseq) was performed, combining samples from both control and KO small intestines. This was done to further confirm BMP2 KO and to identify BMP2-responsive CSF1-producing cells. Flow cytometry was then used to characterize the intestinal MPs in control and KO mice. Results Tim4+ MPs emerged as the primary source of BMP2. Comprehensive analysis using qPCR, RNAscope, and scRNAseq validated the complete KO of BMP2 across all macrophage subsets. The loss of MP-produced BMP2 led to a disruption in MP development. Notably, a marked reduction in DN and Tim4+ MPs was observed following deletion of Bmp2 in MPs, emphasizing the critical role of BMP2-driven CSF1 in sustaining these subsets. CSF1 producing cells co-expressing the cognate BMP receptor in the gut, were predominantly non-hematopoietic tissue cells. Among these, distinct fibroblast populations emerged as a potent but not the sole source of CSF1. Conclusions Our work underscores the involvement of multiple tissue cell populations, revealing an intricate network of interactions that extends beyond fibroblasts. This study unveils the multifaceted nature of tissue-MP interactions and their critical roles in maintaining gut homeostasis. Disturbances of these pathways may pave the way for disease by altering tissue homeostasis. Funding Agencies NSERC