BMP Inhibitor Research Articles

Chrdl1-mediated BMP4 inhibition disrupts the balance between retinal neurons and Müller Glia

Chordin-like 1 (CHRDL1) is a secreted protein that serves as an endogenous antagonist of bone morphogenetic proteins (BMPs). In the developing retina, Bmp4 has been demonstrated to be essential for sustaining the proliferation of progenitor cells and facilitating the differentiation of glial cells. Despite these efforts, the precise effects of Bmp4 inhibition on the developing retina are yet to be fully understood. We sought to address this question by overexpressing Chrdl1 in the developing retina. In this study, we explored the impact of Bmp4 inhibition on the developing mouse retina by conditionally overexpressing the Bmp4 inhibitor Chrdl1. Initially, we characterized the expression patterns of Bmp4 and Chrdl1 in the developing mouse retina from E10.5 to P12.5. Additionally, we utilized various molecular markers to demonstrate that Bmp4 inhibition disrupts both neuronal and Müller glial differentiation in the developing mouse retina. Moreover, through the application of RNA-seq analysis, distinctively expressed retinal genes under the modulation of Bmp4 signaling were discerned, encompassing the upregulation of Id1/2/3/4 and Hes1/5, as well as the downregulation of Neurod1/2/4 and Bhlhe22/23. Lastly, electroretinogram (ERG) and optomotor response (OMR) assays were conducted to illustrate that Bmp4 inhibition impairs the functional connectivity of various cells in the retina and consequently affects visual function. Collectively, this study demonstrates that inhibiting Bmp4 promotes the differentiation of retinal neurons over Müller glia by activating the expression of genes associated with neuron specification. These findings offer molecular insights into the role of Bmp4 signaling in mammalian retinal development.

Epigenetics enters the stage in vascular malformations.

Cerebral arteriovenous malformations represent the most common form of vascular malformations and can cause recurrent bleeding and hemorrhagic stroke. The current issue of the JCI features an article by Zhao et al. describing a mouse model of cerebral arteriovenous malformations. Endothelial cells lacking matrix Gla protein, a BMP inhibitor, underwent epigenetic changes characteristic of an endothelial-to-mesenchymal fate transition. The authors uncovered a two-step process for this transition controlled by the epigenetic regulator histone deacetylase 2 (HDAC2), which controls endothelial cell differentiation, and by enhancer of zeste homolog 1 (EZH1), which suppressed mesenchymal fate. This discovery provides a promising entry point for preventive pharmacological interventions.

Bone morphogenic protein-4 availability in the cardiac microenvironment controls inflammation and fibrosis in autoimmune myocarditis

Myocarditis is an inflammatory heart disease that leads to loss of cardiomyocytes and frequently precipitates fibrotic remodeling of the myocardium, culminating in heart failure. However, the molecular mechanisms underlying immune cell control and maintenance of tissue integrity in the inflamed cardiac microenvironment remain elusive. In this study, we found that bone morphogenic protein-4 (BMP4) gradients maintain cardiac tissue homeostasis by single-cell transcriptomics analyses of inflamed murine and human myocardial tissues. Cardiac BMP pathway dysregulation was reflected by reduced BMP4 serum concentration in patients with myocarditis. Restoration of BMP signaling by antibody-mediated neutralization of the BMP inhibitors gremlin-1 and gremlin-2 ameliorated T cell-induced myocardial inflammation in mice. Moreover, progression to inflammatory cardiomyopathy was blocked through the reduction of fibrotic remodeling and preservation of cardiomyocyte integrity. These results unveil the BMP4–gremlin axis as a druggable pathway for the treatment of myocardial inflammation, limiting the severe sequelae of cardiac fibrosis and heart failure.

Conditioned Medium of Intervertebral Disc Cells Inhibits Osteo-Genesis on Autologous Bone-Marrow-Derived Mesenchymal Stromal Cells and Osteoblasts.

Low back pain (LBP) is associated with the degeneration of human intervertebral discs (IVDs). Despite progress in the treatment of LBP through spinal fusion, some cases still end in non-fusion after the removal of the affected IVD tissue. In this study, we investigated the hypothesis that the remaining IVD cells secrete BMP inhibitors that are sufficient to inhibit osteogenesis in autologous osteoblasts (OBs) and bone marrow mesenchymal stem cells (MSCs). A conditioned medium (CM) from primary human IVD cells in 3D alginate culture was co-cultured with seven donor-matched OB and MSCs. After ten days, osteogenesis was quantified at the transcript level using qPCR to measure the expression of bone-related genes and BMP antagonists, and at the protein level by alkaline phosphatase (ALP) activity. Additionally, cells were evaluated histologically using alizarin red (ALZR) staining on Day 21. For judging ALP activity and osteogenesis, the Noggin expression in samples was investigated to uncover the potential causes. The results after culture with the CM showed significantly decreased ALP activity and the inhibition of the calcium deposit formation in alizarin red staining. Interestingly, no significant changes were found among most bone-related genes and BMP antagonists in OBs and MSCs. Noteworthy, Noggin was relatively expressed higher in human IVD cells than in autologous OBs or MSCs (relative to autologous OB, the average fold change was in 6.9, 10.0, and 6.3 in AFC, CEPC, and NPC, respectively; and relative to autologous MSC, the average fold change was 2.3, 3.4, and 3.2, in AFC, CEPC, and NPC, respectively). The upregulation of Noggin in residual human IVDs could potentially inhibit the osteogenesis of autologous OB and MSC, thus inhibiting the postoperative spinal fusion after discectomy surgery.

Human intestinal organoid-derived PDGFRα + mesenchymal stroma enables proliferation and maintenance of LGR4 + epithelial stem cells

BackgroundIntestinal epithelial cells derived from human pluripotent stem cells (hPSCs) are generally maintained and cultured as organoids in vitro because they do not exhibit adhesion when cultured. However, the three-dimensional structure of organoids makes their use in regenerative medicine and drug discovery difficult. Mesenchymal stromal cells are found near intestinal stem cells in vivo and provide trophic factors to regulate stem cell maintenance and proliferation, such as BMP inhibitors, WNT, and R-spondin. In this study, we aimed to use mesenchymal stromal cells isolated from hPSC-derived intestinal organoids to establish an in vitro culture system that enables stable proliferation and maintenance of hPSC-derived intestinal epithelial cells in adhesion culture.MethodsWe established an isolation protocol for intestinal epithelial cells and mesenchymal stromal cells from hPSCs-derived intestinal organoids and a co-culture system for these cells. We then evaluated the intestinal epithelial cells and mesenchymal stromal cells' morphology, proliferative capacity, chromosomal stability, tumorigenicity, and gene expression profiles. We also evaluated the usefulness of the cells for pharmacokinetic and toxicity studies.ResultsThe proliferating intestinal epithelial cells exhibited a columnar form, microvilli and glycocalyx formation, cell polarity, and expression of drug-metabolizing enzymes and transporters. The intestinal epithelial cells also showed barrier function, transporter activity, and drug-metabolizing capacity. Notably, small intestinal epithelial stem cells cannot be cultured in adherent culture without mesenchymal stromal cells and cannot replaced by other feeder cells. Organoid-derived mesenchymal stromal cells resemble the trophocytes essential for maintaining small intestinal epithelial stem cells and play a crucial role in adherent culture.ConclusionsThe high proliferative expansion, productivity, and functionality of hPSC-derived intestinal epithelial cells may have potential applications in pharmacokinetic and toxicity studies and regenerative medicine.

Loss of Axin1 in limb mesenchymal cells leads to multiple synostoses syndrome-like phenotype in mice

<p>Multiple synostoses syndrome (SYNS) is a disease characterized by the fusion of multiple joints. Unfortunately, the underlying and critical signaling pathways of this disorder remain poorly understood. Given the pivotal role of Wnt/��-catenin signaling in skeletal development and the key regulatory effect of Axin1 and Axin2 in the ��-catenin pathway, limb mesenchymal stem cell (MSC) specific <i>Axin1</i> conditional KO (cKO) mice and <i>Axin1</i>/<i>Axin2</i> double KO (dKO) mice were generated to explore their involvement in joint formation. Abnormalities, such as developmental defects in joints and fusions in multiple joint tissues were observed in both <i>Axin1</i> cKO and <i>Axin1</i>/<i>Axin2</i> dKO mice, which resemble to the characteristics of human SYNS disease including synostoses of carpal and tarsal bones, as well as ankylosis of elbow joint and knee joint. Administration of ��-catenin or BMP inhibitor significantly reversed the joint fusion phenotype in <i>Axin1</i> cKO mice. Our findings suggest that Axin1 plays a key role in joint formation by inhibiting ��-catenin-BMP signaling and could potentially serve as a therapeutic target for SYNS.</p>

BMP and activin receptor membrane bound inhibitor: BAMBI has multiple roles in gene expression and diseases (Review).

BMP and activin membrane-bound inhibitor (BAMBI) is a transmembrane glycoprotein, known as a pseudo-receptor for TGFβ, as, while its extracellular domain is similar to that of type I TGFβ receptors, its intracellular structure is shorter and lacks a serine/threonine phosphokinase signaling motif. BAMBI can regulate numerous biological phenomena, including glucose and lipid metabolism, inflammatory responses, and cell proliferation and differentiation. Furthermore, abnormal expression of BAMBI at the mRNA and protein levels contributes to various human pathologies, including obesity and cancer. In the present review, the structure of BAMBI is briefly introduced and its associated signaling pathways and physiological functions are described. Understanding of BAMBI structure and function may contribute to knowledge regarding the occurrence of diseases, including obesity and diabetes, among others. The present review provides a theoretical foundation for the development of BAMBI as a potential biomarker or therapeutic target.

Circular RNA circSP5 promotes liver metastasis of colorectal cancer via SP5-mediated BAMBI transcription.

Liver metastasis of colorectal cancer (CRC) is a major cause of cancer morbidity and mortality. Circular RNAs (circRNAs) have been widely reported to be implicated in cancer metastasis. This study aims to investigate the effect of circSP5 (has_circ_0057010) on liver metastasis of CRC. Quantitative real-time PCR (RT-qPCR) analysis was performed to detect gene expression. The level of proteins was measured by western blot. The migration and invasion of CRC cells were assessed by wound healing assay and transwell assay. In vivo assays were performed after the construction of the CRC xenograft model and CRC model with liver metastasis. Mechanism analyses were performed via RNA-binding protein immunoprecipitation (RIP), RNA pulldown, luciferase reporter, chromatin immunoprecipitation (ChIP), and DNA pulldown assays. We found that circSP5 is significantly overexpressed in CRC with liver metastasis and its depletion suppresses the progression of CRC with liver metastasis in vitro and in vivo. Moreover, circSP5 enhances the expression of Sp5 transcription factor (SP5) via competitively sponging microRNA (miR)-1249-3p and could regulate BMP and activin membrane-bound inhibitor (BAMBI) via transcriptional activation. CircSP5 promotes the migration, invasion, and epithelial-mesenchymal transition (EMT) of CRC cells via BAMBI. In sum, circSP5 promotes liver metastasis of CRC by up-regulating SP5-mediated BAMBI transcription.

MeCP2 dysfunction prevents proper BMP signaling and neural progenitor expansion in brain organoid.

Sporadic mutations in MeCP2 are a hallmark of Rett syndrome (RTT). Many RTT brain organoid models have exhibited pathogenic phenotypes such as decreased spine density and small size of soma with altered electrophysiological signals. However, previous models are mainly focused on the phenotypes observed in the late phase and rarely provide clues for the defect of neural progenitors which generate different types of neurons and glial cells. We newly established the RTT brain organoid model derived from MeCP2-truncated iPS cells which were genetically engineered by CRISPR/Cas9 technology. By immunofluorescence imaging, we studied the development of NPC pool and its fate specification into glutamatergic neurons or astrocytes in RTT organoids. By total RNA sequencing, we investigated which signaling pathways were altered during the early brain development in RTT organoids. Dysfunction of MeCP2 caused the defect of neural rosette formation in the early phase of cortical development. In total transcriptome analysis, BMP pathway-related genes are highly associated with MeCP2 depletion. Moreover, levels of pSMAD1/5 and BMP target genes are excessively increased, and treatment of BMP inhibitors partially rescues the cell cycle progression of neural progenitors. Subsequently, MeCP2 dysfunction reduced the glutamatergic neurogenesis and induced overproduction of astrocytes. Nevertheless, early inhibition of BMP pathway rescued VGLUT1 expression and suppressed astrocyte maturation. Our results demonstrate that MeCP2 is required for the expansion of neural progenitor cells by modulating BMP pathway at early stages of development, and this influence persists during neurogenesis and gliogenesis at later stages of brain organoid development.

CSNK1D-mediated phosphorylation of HNRNPA2B1 induces miR-25-3p/miR-93-5p maturation to promote prostate cancer cell proliferation and migration through m6A-dependent manner.

It has been reported that heterogeneous nuclear ribonucleoprotein A2/B1 (HNRNPA2B1) is highly expressed in prostate cancer (PCa) and associated with poor prognosis of patients with PCa. Nevertheless, the specific mechanism underlying HNRNPA2B1 functions in PCa remains not clear. In our study, we proved that HNRNPA2B1 promoted the progression of PCa through in vitro and in vivo experiments. Further, we found that HNRNPA2B1 induced the maturation of miR-25-3p/miR-93-5p by recognizing primary miR-25/93 (pri-miR-25/93) through N6-methyladenosine (m6A)-dependent manner. In addition, both miR-93-5p and miR-25-3p were proven as tumor promoters in PCa. Interestingly, by mass spectrometry analysis and mechanical experiments, we found that casein kinase 1 delta (CSNK1D) could mediate the phosphorylation of HNRNPA2B1 to enhance its stability. Moreover, we further proved that miR-93-5p targeted BMP and activin membrane-bound inhibitor (BAMBI) mRNA to reduce its expression, thereby activating transforming growth factor β (TGF-β) pathway. At the same time, miR-25-3p targeted forkhead box O3 (FOXO3) to inactivate FOXO pathway. These results collectively indicated that CSNK1D stabilized HNRNPA2B1 facilitates the processing of miR-25-3p/miR-93-5p to regulate TGF-β and FOXO pathways, resulting in PCa progression. Our findings supported that HNRNPA2B1 might be a promising target for PCa treatment.

Establishment and characterisation of oviductal organoids from farm and companion animals.

Organoid technology has provided a unique opportunity to study early human development and decipher various steps involved in the pathogenesis of disease. The technology is already used in clinics to improve human patient outcomes. However, limited knowledge of the methodologies required to establish organoid culture systems in domestic animals has slowed the advancement and application of organoid technology in veterinary medicine. This is particularly true for the field of reproduction and the application of assisted reproductive technologies (ART). Here, we have developed a platform to grow oviductal organoids from five domestic species - bovine, porcine, equine, feline, and canine. The organoids were grown progressively from single cells derived from the enzymatic digestion of freshly collected infundibular/fimbrial samples. The addition of WNT, TGFβ, BMP, ROCK, and Notch signalling pathway activators or inhibitors to the organoid culture medium suggested remarkable conservation of the molecular signals involved in oviductal epithelial development and differentiation across species. The gross morphology of organoids from all the domestic species was initially similar. However, some differences in size, complexity, and growth rate were subsequently observed and described. After 21days, well-defined and synchronized motile ciliated cells were observed in organoids. Histopathologically, oviductal organoids mimicked their respective native tissue. In summary, we have carried out a detailed cross-species comparison of oviductal organoids, which would be valuable in advancing our knowledge of oviduct physiology and, potentially, help in increasing the success of assisted reproductive technologies.

Expression and Function of BMP and Activin Membrane-Bound Inhibitor (BAMBI) in Chronic Liver Diseases and Hepatocellular Carcinoma.

BAMBI (bone morphogenetic protein and activin membrane-bound inhibitor) is a transmembrane pseudoreceptor structurally related to transforming growth factor (TGF)-β type 1 receptors (TGF-β1Rs). BAMBI lacks a kinase domain and functions as a TGF-β1R antagonist. Essential processes such as cell differentiation and proliferation are regulated by TGF-β1R signaling. TGF-β is the best-studied ligand of TGF-βRs and has an eminent role in inflammation and fibrogenesis. Liver fibrosis is the end stage of almost all chronic liver diseases, such as non-alcoholic fatty liver disease, and at the moment, there is no effective anti-fibrotic therapy available. Hepatic BAMBI is downregulated in rodent models of liver injury and in the fibrotic liver of patients, suggesting that low BAMBI has a role in liver fibrosis. Experimental evidence convincingly demonstrated that BAMBI overexpression is able to protect against liver fibrosis. Chronic liver diseases have a high risk of hepatocellular carcinoma (HCC), and BAMBI was shown to exert tumor-promoting as well as tumor-protective functions. This review article aims to summarize relevant studies on hepatic BAMBI expression and its role in chronic liver diseases and HCC.

The BMP inhibitor follistatin-like 1 (FSTL1) suppresses cervical carcinogenesis.

Follistatin-like 1 (FSTL1) is a cancer-related matricellular secretory protein with contradictory organ-specific roles. Its contribution to the pathogenesis of cervical carcinoma is still not clear. Meanwhile, it is necessary to identify novel candidate genes to understand cervical carcinoma's pathogenesis further and find potential therapeutic targets. We collected cervical carcinoma samples and matched adjacent tissues from patients with the locally-advanced disease and used cervical carcinoma cell lines HeLa and C33A to evaluate the effects of FSTL1 on CC cells. The mRNA transcription and protein expression of FSTL1 in cervical carcinoma tumor biopsy tissues were lower than those of matched adjacent tissues. Patients with a lower ratio of FSTL1 mRNA between the tumor and its matched adjacent tissues showed a correlation with the advanced cervical carcinoma FIGO stages. High expression of FSTL1 markedly inhibited the proliferation, motility, and invasion of HeLa and C33A. Regarding mechanism, FSTL1 plays its role by negatively regulating the BMP4/Smad1/5/9 signaling. Our study has demonstrated the tumor suppressor effect of FSTL1, and these findings suggested a potential therapeutic target and biomarker for cervical carcinoma.

SMOC2 promoted vascular smooth muscle cell proliferation, migration, and extracellular matrix degradation by activating BMP/TGF-β1 signaling pathway.

A widespread degenerative condition of the aorta, abdominal aortic aneurysm (AAA), severely endangers the health of middle-aged and elderly people. SPARC related modular calcium binding2 (SMOC2) is upregulated in the carotid arteries of rats with atherosclerotic lesions, but its function in AAA is still unknown. Therefore, the aim of this research was to evaluate the function of SMOC2 in AAA. The results showed that in the AAA tissues, SMOC2 expression was upregulated compared with healthy controls. Overexpression of SMOC2 promoted vascular smooth muscle cells (VSMCs) proliferation, migration, and extracellular matrix (ECM) degradation. In contrast, silence of SMOC2 inhibited VSMCs proliferation, migration, and ECM degradation. Overexpression of SMOC2 promoted BMP and TGF-β1 expression and silence of SMOC2 had an opposite effect. Besides, inhibition of BMP or TGF-β1 suppressed VSMCs cell proliferation, migration, and ECM degradation. Moreover, inhibition BMP or TGF-β1 reversed the promotive effects of SMOC2 overexpression on VSMCs proliferation, migration, and ECM degradation. SMOC2 may affecte the formation of AAA by upregulating BMP and TGF-β1 to regulate the proliferation, migration, and ECM degradation of VSMCs.

FGF10 ameliorates lipopolysaccharide-induced acute lung injury in mice via the BMP4-autophagy pathway.

Introduction: Damage to alveolar epithelial cells caused by uncontrolled inflammation is considered to be the main pathophysiological change in acute lung injury. FGF10 plays an important role as a fibroblast growth factor in lung development and lung diseases, but its protective effect against acute lung injury is unclear. Therefore, this study aimed to investigate protective effect and mechanism of FGF10 on acute lung injury in mice. Methods: ALI was induced by intratracheal injection of LPS into 57BL/6J mice. Six hours later, lung bronchoalveolar lavage fluid (BALF) was acquired to analyse cells, protein and the determination of pro-inflammatory factor levels, and lung issues were collected for histologic examination and wet/dry (W/D) weight ratio analysis and blot analysis of protein expression. Results: We found that FGF10 can prevent the release of IL-6, TNF-α, and IL-1β, increase the expression of BMP4 and autophagy pathway, promote the regeneration of alveolar epithelial type Ⅱ cells, and improve acute lung injury. BMP4 gene knockdown decreased the protective effect of FGF10 on the lung tissue of mice. However, the activation of autophagy was reduced after BMP4 inhibition by Noggin. Additionally, the inhibition of autophagy by 3-MA also lowered the protective effect of FGF10 on alveolar epithelial cells induced by LPS. Conclusions: These data suggest that the protective effect of FGF10 is related to the activation of autophagy and regeneration of alveolar epithelial cells in an LPS-induced ALI model, and that the activation of autophagy may depend on the increase in BMP4 expression.

The Role of Matrix Metalloproteinase-13 (MMP13) in TGFβ/BMP Pathway Regulation of Fibro-Adipogenic Progenitor (FAP) Differentiation.

Muscle fibrosis and fatty infiltration (FI) are common complications seen in various muscle disease states. Recent studies indicate that muscle residential fibro/adipogenic progenitors (FAPs) are the major cellular source for muscle fibrosis and FI. We previously showed that MMP13 knockout (KO) mice have significantly increased FI, suggesting an important role of MMP13 in muscle FI. However, how MMP13 affects the differentiation of FAPs remains unknown. In order to assess the role of MMP-13 on FAP differentiation, we isolated FAPs from wildtype C57BL/6 and MMP13 knock out mice with FACS using CD31-, CD45-, Integrin α7- and Sca-1+ markers. FAPs were cultured in 24 well plate after FACS.in standard media till 80% confluent and then switched to adipogenic medium. In order to study the role of TGFβ and BMP in their differentiation, FAPs from both wildtype and MMP13 KO mice were treated with TGFβ1 (5 ng/ml). For MMP13 inhibitor treatment, FAPs from wildtype mice were incubated in adipogenic medium containing 10 µM MMP13 inhibitor (or vehicle) for 2 weeks. Immunofluorescence and gene expression analysis were used to assess FAP adipogenic and fibrogenic differentiation. FAPs were stained with Perilipin A (FITC, adipogenesis marker) and αSMA (Red, fibroblast marker), and DAPI. Real time PCR was performed for gene expression evaluation. A two-tailed Anova was used for statistical comparisons between groups, with p ≤ 0.05. Data are presented as mean ± standard deviation. In this study, we isolated FAPs from wildtype C57BL/6 and MMP13 KO mice and evaluated their adipogenic and fibrogenic differentiation in vitro. MMP13 KO FAPs demonstrated enhanced adipogenesis but reduced fibrogenesis compared to wildtype FAPs. Treating wildtype FAPs with an MMP13 inhibitor simulated phenotypes seen in MMP13 KO FAPs. In order to assess the role of MMP13 on TGFβ/BMP signaling in regulating FAP differentiation, we treated wildtype and MMP13 KO FAPs with TGFβ1, BMP7, TGFβ inhibitor, and BMP inhibitor. TGFβ1 treatment significantly enhanced fibrogenesis, but inhibited adipogenesis of wildtype FAPs. However, treatment with BMP7 showed the opposite effect. Interestingly, the effect of TGFβ1/BMP7 was voided in MMP13 KO FAPs. Treating wildtype FAPs with MMP13 inhibitor also abolished the effect of TGFβ1/BMP7 in FAP differentiation. Results from this study showed that TGFβ1 inhibits FAP adipogenesis but stimulates FAP fibrogenesis. BMP7 was shown to promote FAP adipogenesis but reduce its fibrogenesis. The role of the TGFβ/BMP signaling pathway regulating FAP differentiation was found to be MMP13 dependent. This study suggests that MMP13 is a critical downstream effector in TGFβ/BMP pathway which may serve as a new therapeutic target for muscle fibrosis and FI.

BMP and activin membrane-bound inhibitor regulate connective tissue growth factor controlling mesothelioma cell proliferation

BackgroundMalignant mesothelioma (MM) is an aggressive mesothelial cell cancer type linked mainly to asbestos inhalation. MM characterizes by rapid progression and resistance to standard therapeutic modalities such as surgery, chemotherapy, and radiotherapy. Our previous studies have suggested that tumor cell-derived connective tissue growth factor (CTGF) regulates the proliferation of MM cells as well as the tumor growth in mouse xenograft models.MethodsIn this study, we knock downed the bone morphogenetic protein and activin membrane-bound inhibitor (BAMBI) and CTGF in MM cells and investigated the relationship between both and their impact on the cell cycle and cell proliferation.ResultsThe knockdown of CTGF or BAMBI reduced MM cell proliferation. In contrast to CTGF knockdown which decreased BAMBI, knockdown of BAMBI increased CTGF levels. Knockdown of either BAMBI or CTGF reduced expression of the cell cycle regulators; cyclin D3, cyclin-dependent kinase (CDK)2, and CDK4. Further, in silico analysis revealed that higher BAMBI expression was associated with shorter overall survival rates among MM patients.ConclusionsOur findings suggest that BAMBI is regulated by CTGF promoting mesothelioma growth by driving cell cycle progression. Therefore, the crosstalk between BAMBI and CTGF may be an effective therapeutic target for MM treatment.

A novel BMP2 secretagogue ameliorates glucocorticoid induced oxidative stress in osteoblasts by activating NRF2 dependent survival while promoting Wnt/β-catenin mediated osteogenesis.

In our previous study, a novel BMP2 secretagogue was synthesized belonging to a class of galloyl conjugates of flavanones, with remarkable osteogenic potential that promoted bone regeneration. We aimed to establish the protective effect of our compound against bone loss that co-exists with excess Glucocorticoid (GC) therapy. GC therapy induces osteoblast damage leading to apoptosis by increasing reactive oxygen species (ROS). Our results delineate that compound 5e (a BMP2 secretagogue) activates NRF2 signalling to counter the disturbed cellular redox homeostasis and escalate osteoblast survival as assessed by Western blot and immunocytochemistry. Depletion of NRF2 by siRNA blocked activation of the NRF2/HO-1 pathway, magnified oxidative stress, increased apoptosis and abrogated the protective effects of compound 5e. 5e, on the other hand, increased ALP, mineralization activity, and promoted osteoblast differentiation by activating WNT/β-catenin signalling in BMP2 dependent manner, validated by Western blot of WNT3A, SOST, GSK3-β and β-catenin nuclear translocation. Treatment of 5e in presence of BMP inhibitor noggin attenuated the osteogenic efficacy and minimized Wnt//β-catenin signalling in presence of dexamethasone. Our compound prevents GC challenged trabecular and cortical bone loss assessed by micro-CT and promotes bone formation and osteocyte survival determined by calcein labelling and TUNEL assay in GC treated animals. The osteogenic potential of the compound was authenticated by bone turnover markers. On a concluding note, compounds with BMP upregulation can be potential therapeutics for the prevention and treatment of glucocorticoid-induced osteoporosis.

Directed differentiation of human pluripotent stem cells into diverse organ-specific mesenchyme of the digestive and respiratory systems.

Development of visceral organs such as the esophagus, lung, liver and stomach are coordinated by reciprocal signaling interactions between the endoderm and adjacent mesoderm cells in the fetal foregut. Although the recent successes in recapitulating developmental signaling in vitro has enabled the differentiation of human pluripotent stem cells (hPSCs) into various types of organ-specific endodermal epithelium, the generation of organ-specific mesenchyme has received much less attention. This is a major limitation in ongoing efforts to engineer complex human tissue. Here, we describe a protocol to differentiate hPSCs into different types of organ-specific mesoderm, leveraging signaling networks and molecular markers elucidated from single-cell transcriptomics of mouse foregut organogenesis. Building on established methods, hPSC-derived lateral plate mesoderm treated with either retinoic acid (RA) or RA together with a Hedgehog (HH) agonist generates posterior or anterior foregut splanchnic mesoderm, respectively, after 4-d cultures. These are directed into organ-specific mesenchyme lineages by the combinatorial activation or inhibition of WNT, BMP, RA or HH pathways from days 4 to 7 in cultures. By day 7, the cultures are enriched for different types of mesoderm with distinct molecular signatures: 60-90% pure liver septum transversum/mesothelium-like, 70-80% pure liver-like fibroblasts and populations of ~35% respiratory-like mesoderm, gastric-like mesoderm or esophageal-like mesoderm. This protocol can be performed by anyone with moderate experience differentiating hPSCs, provides a novel platform to study human mesoderm development and can be used to engineer more complex foregut tissue for disease modeling and regenerative medicine.

Repair of Retinal Degeneration by Human Amniotic Epithelial Stem Cell-Derived Photoreceptor-like Cells.

The loss of photoreceptors is a major event of retinal degeneration that accounts for most cases of untreatable blindness globally. To date, there are no efficient therapeutic approaches to treat this condition. In the present study, we aimed to investigate whether human amniotic epithelial stem cells (hAESCs) could serve as a novel seed cell source of photoreceptors for therapy. Here, a two–step treatment with combined Wnt, Nodal, and BMP inhibitors, followed by another cocktail of retinoic acid, taurine, and noggin induced photoreceptor–like cell differentiation of hAESCs. The differentiated cells demonstrated the morphology and signature marker expression of native photoreceptor cells and, intriguingly, bore very low levels of major histocompatibility complex (MHC) class II molecules and a high level of non–classical MHC class I molecule HLA–G. Importantly, subretinal transplantation of the hAESCs–derived PR–like cells leads to partial restoration of visual function and retinal structure in Royal College of Surgeon (RCS) rats, the classic preclinical model of retinal degeneration. Together, our results reveal hAESCs as a potential source of functional photoreceptor cells; the hAESCs–derived photoreceptor–like cells could be a promising cell–replacement candidate for therapy of retinal degeneration diseases.