GDF10 is related to obesity as an adipokine derived from subcutaneous adipose tissue.

Introduction: Adipokines are proteins that are secreted by the adipose tissue. Although they are associated with obesity-related metabolic disorders, most studies have focused on adipokines expressed by visceral adipose tissue (VAT). This study aimed to identify the adipokine potentially derived from subcutaneous adipose tissue (SAT) and its clinical significance. Methods: Samples of SAT and VAT were obtained from six adult male patients who underwent laparoscopic surgery for benign gall bladder disease. Differentially expressed genes were analyzed by subjecting the samples to RNA sequencing. The serum concentration of selected proteins according to body mass index (BMI) was analyzed in 58 individuals. Results: GDF10 showed significantly higher expression in the SAT, as per RNA sequencing (fold change = 5.8, adjusted P value = 0.009). Genes related to insulin response, glucose homeostasis, lipid homeostasis, and fatty acid metabolism were suppressed when GDF10 expression was high in SAT, as per genotype-tissue expression data. The serum GDF10 concentration was higher in participants with BMI ≥ 25 kg/m2 (n = 35, 2674 ± 441 pg/mL) than in those with BMI < 25 kg/m2 (n = 23, 2339 ± 639 pg/mL; P = 0.022). There was a positive correlation between BMI and serum GDF10 concentration (r = 0.308, P = 0.019). Conclusions: GDF10 expression was higher in SAT than in VAT. Serum GDF10 concentration was high in patients with obesity. Therefore, GDF10 could be a SAT-derived protein related to obesity.

Brown Adipose Tissue and BMP3b Decrease Injury in Cardiac Ischemia-Reperfusion.

BACKGROUND: Despite advances in treatment, myocardial infarction (MI) is a leading cause of heart failure and death worldwide, with both ischemia and reperfusion (I/R) causing cardiac injury. A previous study using a mouse model of nonreperfused MI showed activation of brown adipose tissue (BAT). Recent studies showed that molecules secreted by BAT target the heart. We investigated whether BAT attenuates cardiac injury in I/R and sought to identify potential cardioprotective proteins secreted by BAT. METHODS: Myocardial I/R surgery with or without BAT transplantation was performed in wild-type (WT) mice and in mice with impaired BAT function (uncoupling protein 1 [Ucp1]-deficient mice). To identify potential cardioprotective factors produced by BAT, RNA-seq (RNA sequencing) was performed in BAT from WT and Ucp1-/- mice. Subsequently, myocardial I/R surgery with or without BAT transplantation was performed in Bmp3b (bone morphogenetic protein 3b)-deficient mice, and WT mice subjected to myocardial I/R were treated using BMP3b. RESULTS: Dysfunction of BAT in mice was associated with larger MI size after I/R; conversely, augmenting BAT by transplantation decreased MI size. We identified Bmp3b as a protein secreted by BAT after I/R. Compared with WT mice, Bmp3b-deficient mice developed larger MIs. Increasing functional BAT by transplanting BAT from WT mice to Bmp3b-deficient mice reduced I/R injury whereas transplanting BAT from Bmp3b-deficient mice did not. Treatment of WT mice with BMP3b before reperfusion decreased MI size. The cardioprotective effect of BMP3b was mediated through SMAD1/5/8. In humans, the plasma level of BMP3b increased after MI and was positively correlated with the extent of cardiac injury. CONCLUSIONS: The results of this study suggest a cardioprotective role of BAT and BMP3b, a protein secreted by BAT, in a model of I/R injury. Interventions increasing BMP3b levels or targeting Smad 1/5 may represent novel therapeutic approaches to decrease myocardial damage in I/R injury.

Ly-6A-Induced Growth Inhibition and Cell Death in a Transformed CD4+ T Cell Line: Role of Tumor Necrosis Factor-α.

Ly-6A, a member of the Ly-6/uPAR supergene family of proteins, is a cell adhesion and cell signaling protein. Signaling through Ly-6A activates the cell-intrinsic apoptotic cell death pathway in CD4+ T cell lines, as indicated by the release of cytochrome C, and activation of caspases 9 and 3. In addition, Ly-6A induces cytokine production and growth inhibition. The mechanism underlying the distinct cellular responses that are triggered by engaging Ly-6A protein has remained unknown. To examine the relatedness of these distinct responses, we have quantified the production of pro-apoptotic, growth inhibitory and tumor suppressive cytokines, such as TNF-α, TGF-ß and a related protein GDF-10, in response to Ly-6A signaling. Anti-Ly-6A monoclonal antibody-induced activation of YH16.33 CD4+ T cell line generated low levels of TGF-ß and GDF-10 but elevated levels of TNF-α. Blocking the biological activity of TNF-α resulted in reduced Ly-6A-induced apoptosis in T cells. The Ly-6A-induced response in the T cell line was distinct, as signaling through the antigen receptor complex did not cause growth inhibition and apoptosis despite high levels of TGF-ß and GDF-10 that were detected in these cultures. Additionally, in response to antigen receptor complex signaling, lower amount of TNF-α was detected. These results indicate the contribution of TNF-α in the observed Ly-6A-induced growth inhibition and apoptosis and provide a mechanistic explanation for the biologically distinct responses observed in CD4+ T cells after engaging Ly-6A protein. Additionally, the findings reported here will aid in the understanding of inhibitory signaling initiated by Ly-6A protein, especially in the context of its potential immune checkpoint inhibitory role in T cells.

GDF-10 Induces an Inhibitory Effect on Epithelial-Mesenchymal Transition of Laryngeal Cancer via LPR4.

BACKGROUND: Growth differentiation factor-10 (GDF-10), a member of the TGF-ß superfamily, plays a crucial role in cell proliferation and differentiation. In some tumors, GDF-10 can act as a tumor suppressor to inhibit tumor progression, but its role in posterior squamous cell carcinoma has not been reported yet. METHODS: The aim of this study was to investigate the effect of GDF-10 on the epithelial-mesenchymal transition of laryngeal squamous cell carcinoma, and to provide new ideas for future targets in the treatment of laryngeal squamous carcinoma. RESULTS: The effect of GDF-10 on tumor growth was detected; bioinformatics analysis was performed to predict the downstream targets of GDF-10, and RT-PCR and western blot were performed to detect the expression levels of target genes and proteins, respectively. CONCLUSION: Our findings support that GDF-10 can inhibit the proliferation, migration, and invasion, and promote apoptosis of laryngeal carcinoma AMC-HN-8 cells. GDF-10 inhibits the EMT of laryngeal carcinoma through LRP4 and thus inhibits the progression of laryngeal carcinoma.

BMP3b Is a Novel Antifibrotic Molecule Regulated by Meflin in Lung Fibroblasts.

Fibroblasts play a central role in the lung fibrotic process. Our recent study identified a novel subpopulation of lung fibroblasts expressing meflin (mesenchymal stromal cell- and fibroblast-expressing Linx paralogue), antifibrotic properties of which were confirmed by murine lung fibrosis model. Meflin-expressing fibroblasts were resistant to fibrogenesis induced by TGF-ß (transforming growth factor-ß), but its underlying mechanisms remain unknown. In this study, evaluation of a silica-nanoparticle-induced lung fibrosis model confirmed the antifibrotic effect of meflin via the regulation of TGF-ß signaling. We conducted comparative gene expression profiling in lung fibroblasts, which identified growth differentiation factor 10 (Gdf10) encoding bone morphogenic protein 3b (BMP3b) as the most downregulated gene in meflin-deficient cells under the profibrotic condition with TGF-ß. We hypothesized that BMP3b can be an effector molecule playing an antifibrotic role downstream of meflin. As suggested by single-cell transcriptomic data, restricted expressions of Gdf10 (Bmp3b) in stromal cells including fibroblasts were confirmed. We examined possible antifibrotic properties of BMP3b in lung fibroblasts and demonstrated that Bmp3b-null fibroblasts were more susceptible to TGF-ß-induced fibrogenic changes. Furthermore, Bmp3b-null mice exhibited exaggerated lung fibrosis induced by silica-nanoparticles in vivo. We also demonstrated that treatment with recombinant BMP3B was effective against TGF-ß-induced fibrogenesis in fibroblasts, especially in the suppression of excessive extracellular matrix production. These lines of evidence suggested that BMP3b is a novel humoral effector molecule regulated by meflin which exerts antifibrotic properties in lung fibroblasts. Supplementation of BMP3B could be a novel therapeutic strategy for fibrotic lung diseases.

Cancer-associated fibroblasts promote tumor progression by lncRNA-mediated RUNX2/GDF10 signaling in oral squamous cell carcinoma.

Cancer-associated fibroblasts (CAF) are the most abundant stromal cells in tumor and exert a pro-tumoral effect in cancer progression. Numerous evidence shows long non-coding RNA (lncRNA) abnormally regulates gene expression in various cancers. However, little is known about the role of lncRNA in the interaction between CAF and cancer cells. Here, we first identify an uncharacterized lncRNA, LOC100506114, which is significantly upregulated in CAF and is involved in the functional transformation of normal fibroblasts (NF) and CAF. Expression of LOC100506114 enhances the expression of fibroblast activation protein alpha and α-smooth muscle actin in NF and promotes malignant characteristics of NF and CAF in vivo and in vitro. The profile of gene co-expression analysis shows that growth differentiation factor 10 (GDF10) is positively correlated with the expression of LOC100506114. CAF promote stromal fibroblast activation and the proliferation and migration of tumor cells by secreting GDF10. Our data demonstrate that lncRNA plays a critical role in the interplay of stromal fibroblasts and tumor cells in oral squamous cell carcinoma.

Growth differentiation factor 10 induces angiogenesis to promote wound healing in rats with diabetic foot ulcers by activating TGF-ß1/Smad3 signaling pathway.

Background: Diabetic foot ulcer (DFU) represents a highly-prevalent complication of diabetes mellitus (DM). Herein, the current study sought to identify the role of growth differentiation factor 10 (GDF-10) in wound healing in DFU via regulation of the transforming growth factor-beta 1 (TGF-ß1)/Smad3 pathway. Methods: DM- and DFU-related microarray datasets GSE29221 and GSE134431 were firstly retrieved, and weighted gene co-expression network analysis (WGCNA) was carried out to construct a co-expression network affecting wound healing in DFU, followed by differential analysis. A protein-protein interaction (PPI) network of the DFU-related genes was subsequently constructed, and the core genes and signaling pathways in DFU were screened with the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional analyses. A DFU rat model was constructed for mechanism verification of the effect of GDF-10 on wound healing in DFU. Results: WGCNA screened five co-expression modules, and the brown module was most closely-related to DM. Clustering analysis screened 4417 candidate genes, of which 175 differential genes were associated with wound healing, further involved in TGF-ß1/Smad3 signaling pathway regulation of wound healing in DFU. The PPI network analysis predicted that GDF-10 might regulate the TGF-ß1/Smad3 signaling pathway to participate in DFU development. Results of animal experimentation showed that the wound healing rates of NFU, DFU, DFU + GDF and GDF + SIS3 groups on the 22nd day were (87.66 ± 6.80)%, (56.31 ± 7.29)%, (71.64 ± 9.43)% and (55.09 ± 7.13)%, respectively. Besides, the expression of TGF-ß1 in NFU, DFU, DFU + GDF and GDF + SIS3 groups was 0.988 ± 0.086, 0.297 ± 0.036, 0.447 ± 0.044, and 0.240 ± 0.050, respectively, and that of Smad3 was 1.009 ± 0.137, 0.145 ± 0.017, 0.368 ± 0.048, and 0.200 ± 0.028, respectively. Specifically, GDF-10 exerted a significant diminishing effect on fasting blood glucose level, and promoted wound healing in DFU rats, in addition to up-regulation of VEGF, FGF, Ang-1, TGF-ß1, Smad3 and enhancement of IL-1b, IL-6, TNF-a and MMP-9, thereby promoting fibroblast proliferation, collagen deposition and angiogenesis. Conclusions: Our findings highlight that GDF-10 may promote angiogenesis by activating TGF-ß1/Smad3 signaling, thereby promoting wound healing in DFU rats.

Transgenic Expression of Bmp3b in Mesenchymal Progenitors Mitigates Age-Related Muscle Mass Loss and Neuromuscular Junction Degeneration.

Skeletal muscle is a vital organ for a healthy life, but its mass and function decline with aging, resulting in a condition termed sarcopenia. The etiology of sarcopenia remains unclear. We recently demonstrated that interstitial mesenchymal progenitors are essential for homeostatic muscle maintenance, and a diminished expression of the mesenchymal-specific gene Bmp3b is associated with sarcopenia. Here, we assessed the protective function of Bmp3b against sarcopenia by generating conditional transgenic (Tg) mice that enable a forced expression of Bmp3b specifically in mesenchymal progenitors. The mice were grown until they reached the geriatric stage, and the age-related muscle phenotypes were examined. The Tg mice had significantly heavier muscles compared to control mice, and the type IIB myofiber cross-sectional areas were preserved in Tg mice. The composition of the myofiber types did not differ between the genotypes. The Tg mice showed a decreasing trend of fibrosis, but the degree of fat infiltration was as low as that in the control mice. Finally, we observed the preservation of innervated neuromuscular junctions (NMJs) in the Tg muscle in contrast to the control muscle, where the NMJ degeneration was conspicuous. Thus, our results indicate that the transgenic expression of Bmp3b in mesenchymal progenitors alleviates age-related muscle deterioration. Collectively, this study strengthens the beneficial role of mesenchymal Bmp3b against sarcopenia and suggests that preserving the youthfulness of mesenchymal progenitors may be an effective means of combating sarcopenia.

Long noncoding RNA ZFPM2-AS1 acts as a miRNA sponge and promotes cell invasion through regulation of miR-139/GDF10 in hepatocellular carcinoma.

BACKGROUND: Emerging evidence has shown that dysregulated expression of long noncoding RNAs (lncRNAs) is implicated in liver hepatocellular carcinoma (HCC). However, the role and molecular mechanism of differentially expressed lncRNAs in HCC has not been fully explained. METHODS: The expression profiles of lncRNAs in HCC samples were derived from microarrays analysis or downloaded from The Cancer Genome Atlas (TCGA), and their correlation with prognosis and clinical characteristics were further analyzed. Silencing of lncRNA ZFPM2-AS1 was conducted to assess the effect of ZFPM2-AS1 in vitro. The miRcode and Target Scan databases were used to determine the lncRNA-miRNA-mRNA interactions. The biological functions were demonstrated by luciferase reporter assay, western blotting, PCR and rescue experiments. RESULTS: The expression level of lncRNA ZFPM2-AS1 was significantly higher in HCC tissues than in adjacent normal tissues, and higher ZFPM2-AS1 was remarkably related to poor survival. Functionally, silencing of lncRNA ZFPM2-AS1 inhibited cell proliferation, migration, invasion and promoted cell apoptosis in vitro. Bioinformatics analysis based on the miRcode and TargetScan databases showed that lncRNA ZFPM2-AS1 regulated GDF10 expression by competitively binding to miR-139. miR-139 and downregulated GDF10 reversed cell phenotypes caused by lncRNA ZFPM2-AS1 by rescue analysis. CONCLUSIONS: ZFPM2-AS1, an upregulated lncRNA in HCC, was associated with malignant tumor phenotypes and worse patient survival. ZFPM2-AS1 regulated the progression of HCC by acting as a competing endogenous RNA (ceRNA) to competitively bind to miR-139 and regulate GDF10 expression. Our study provides new insight into the posttranscriptional regulation mechanism of lncRNA ZFPM2-AS1 and suggests that ZFPM2-AS1/miR-139/GDF10 may act as a potential therapeutic target and prognostic biomarker for HCC.

Klf14 is an imprinted transcription factor that regulates placental growth.

INTRODUCTION: Imprinted genes are preferentially expressed from one parentally inherited allele, and many are crucial to the regulation of placental function and fetal growth. Murine Krüppel-like factor 14 (Klf14) is a maternally expressed imprinted transcription factor that is a component of the Mest imprinted gene cluster on mouse chromosome 6. We sought to determine if loss of Klf14 expression alters the course of normal mouse extraembryonic development. We also used high-throughput RNA sequencing (RNAseq) to identify a set of differentially expressed genes (DEGs) in placentas with loss of Klf14. METHODS: We generated a Klf14 knockout (Klf14null) mouse using recombineering and transgenic approaches. To identify DEGs in the mouse placenta we compared mRNA transcriptomes derived from 17.5dpc Klf14matKO and wild-type littermate placentas by RNAseq. Candidate DEGs were confirmed with quantitative reverse transcription PCR (qPCR) on an independent cohort of male and female gestational age matched Klf14matKO placentas. RESULTS: We found that 17.5dpc placentas inheriting a maternal null allele (Klf14matKO) had a modest overgrowth phenotype and a near complete ablation of Klf14 expression. However, there was no effect on fetal growth. We identified 20 DEGs differentially expressed in Klf14matKO placentas by RNAseq, and subsequently validated five that are highly upregulated (Begain, Col26a1, Fbln5, Gdf10, and Nell1) by qPCR. The most enriched functional gene-networks included those classified as regulating cellular development and metabolism. CONCLUSION: These results suggest that loss of the maternal Klf14 locus in the mouse placenta acts results in changes in gene expression patterns that modulate placental growth.

EPO promotes axonal sprouting via upregulating GDF10.

Erythropoietin (EPO) has an exact neuroprotective effect on stroke. However, it remains unknown whether it participates in axonal sprouting after neuron damage. Growth and differentiation factor 10 (GDF10) has been shown to be a trigger of axonal sprouting after stroke. Hence, it was hypothesized that EPO promotes axonal sprouting mainly through GDF10. In the present in vitro experiment, it was found that EPO could promote axonal sprouting and GDF10 expression in a dose-dependent manner. The knockdown of GDF10 using siRNA abolished the effect of EPO-mediated axonal sprouting, indicating that GDF10 is the executor of EPO-mediated axonal sprouting. The treatment of neurons with nuclear factor-kappaB (NF-κB) inhibitor JSH-23 could inhibit the accumulation of NF-κB phospho-p65 (p-p65) in the nucleus, the upregualtion of GDF10 and extending of axonal length. Furthermore, the addition of Janus kinase 2 (JAK2) inhibitor CEP-33779 or phosphoinositide 3-kinase (PI3K) inhibitor LY294002 to the culture medium also blocked the nuclear translocation of p-p65, the expression of GDF10, and axonal sprouting, suggesting that EPO induces axonal sprouting via activating cellular JAK2 and PI3K signaling. Impeding JAK2 signaling with CEP-33779 can suppress the phosphorylation of PI3K, and this confirms that the upstream of PI3K signaling is JAK2. These present results provide a novel insight into the role of EPO and the molecular mechanism of axonal sprouting, which is beneficial for the development of novel approaches for neurological recovery after brain injury, including stroke.

GDF10 blocks hepatic PPARγ activation to protect against diet-induced liver injury.

OBJECTIVE: Growth differentiation factors (GDFs) and bone-morphogenic proteins (BMPs) are members of the transforming growth factor ß (TGFß) superfamily and are known to play a central role in the growth and differentiation of developing tissues. Accumulating evidence, however, demonstrates that many of these factors, such as BMP-2 and -4, as well as GDF15, also regulate lipid metabolism. GDF10 is a divergent member of the TGFß superfamily with a unique structure and is abundantly expressed in brain and adipose tissue; it is also secreted by the latter into the circulation. Although previous studies have demonstrated that overexpression of GDF10 reduces adiposity in mice, the role of circulating GDF10 on other tissues known to regulate lipid, like the liver, has not yet been examined. METHODS: Accordingly, GDF10-/- mice and age-matched GDF10+/+ control mice were fed either normal control diet (NCD) or high-fat diet (HFD) for 12 weeks and examined for changes in liver lipid homeostasis. Additional studies were also carried out in primary and immortalized human hepatocytes treated with recombinant human (rh)GDF10. RESULTS: Here, we show that circulating GDF10 levels are increased in conditions of diet-induced hepatic steatosis and, in turn, that secreted GDF10 can prevent excessive lipid accumulation in hepatocytes. We also report that GDF10-/- mice develop an obese phenotype as well as increased liver triglyceride accumulation when fed a NCD. Furthermore, HFD-fed GDF10-/- mice develop increased steatosis, endoplasmic reticulum (ER) stress, fibrosis, and injury of the liver compared to HFD-fed GDF10+/+ mice. To explain these observations, studies in cultured hepatocytes led to the observation that GDF10 attenuates nuclear peroxisome proliferator-activated receptor γ (PPARγ) activity; a transcription factor known to induce de novo lipogenesis. CONCLUSION: Our work delineates a hepatoprotective role of GDF10 as an adipokine capable of regulating hepatic lipid levels by blocking de novo lipogenesis to protect against ER stress and liver injury.

GDF10 inhibits proliferation and epithelial-mesenchymal transition in triple-negative breast cancer via upregulation of Smad7.

Triple-negative breast cancer (TNBC) cannot be treated with current hormonal therapies and has a higher risk of relapse than other breast cancers. To identify potential therapeutic targets for TNBC, we conducted microRNA sequencing (RNA-Seq) in human TNBC specimens and tumor-matched controls. We found that growth differentiation factor-10 (GDF10), a member of the TGF-ß superfamily, was downregulated in tumor samples. Further analysis of GDF10 expression in a larger set of clinical TNBC samples using qPCR confirmed its downregulation and association with parameters of disease severity. Using human-derived TNBC cell lines, we carried out GDF10 under- and overexpression experiments, which showed that GDF10 loss promoted cell proliferation and invasion. By contrast, overexpression of GDF10 inhibited proliferation, invasion, and epithelial mesenchymal transition (EMT) via upregulation of Smad7 and E-Cadherin, downregulation of p-Smad2 and N-Cadherin, and reduction of nuclear Smad4 expression. In addition, overexpression of GDF10 reduced tumor burden and induced apoptosis in a TNBC xenograft mouse model. These findings indicate that GDF10 acts as a tumor suppressor in mammary epithelial cells that limits proliferation and suppresses EMT. Efforts aimed at restoring GDF10 expression may thus bring a long-sought therapeutic alternative in the treatment of patients with TNBC.

The caudo-ventral pallium is a novel pallial domain expressing Gdf10 and generating Ebf3-positive neurons of the medial amygdala.

In rodents, the medial nucleus of the amygdala receives direct inputs from the accessory olfactory bulbs and is mainly implicated in pheromone-mediated reproductive and defensive behaviors. The principal neurons of the medial amygdala are GABAergic neurons generated principally in the caudo-ventral medial ganglionic eminence and preoptic area. Beside GABAergic neurons, the medial amygdala also contains glutamatergic Otp-expressing neurons cells generated in the lateral hypothalamic neuroepithelium and a non-well characterized Pax6-positive population. In the present work, we describe a novel glutamatergic Ebf3-expressing neuronal subpopulation distributed within the periphery of the postero-ventral medial amygdala. These neurons are generated in a pallial domain characterized by high expression of Gdf10. This territory is topologically the most caudal tier of the ventral pallium and accordingly, we named it Caudo-Ventral Pallium (CVP). In the absence of Pax6, the CVP is disrupted and Ebf3-expressing neurons fail to be generated. Overall, this work proposes a novel model of the neuronal composition of the medial amygdala and unravels for the first time a new novel pallial subpopulation originating from the CVP and expressing the transcription factor Ebf3.

Treatment with albumin-hydroxyoleic acid complex restores sensorimotor function in rats with spinal cord injury: Efficacy and gene expression regulation.

Sensorimotor dysfunction following incomplete spinal cord injury (SCI) is often characterized by paralysis, spasticity and pain. Previously, we showed that intrathecal (i.t.) administration of the albumin-oleic acid (A-OA) complex in rats with SCI produced partial improvement of these symptoms and that oral 2-hydroxyoleic acid (HOA, a non-hydrolyzable OA analogue), was efficacious in the modulation and treatment of nociception and pain-related anxiety, respectively. Here we observed that intrathecal treatment with the complex albumin-HOA (A-HOA) every 3 days following T9 spinal contusion injury improved locomotor function assessed with the Rotarod and inhibited TA noxious reflex activity in Wistar rats. To investigate the mechanism of action of A-HOA, microarray analysis was carried out in the spinal cord lesion area. Representative genes involved in pain and neuroregeneration were selected to validate the changes observed in the microarray analysis by quantitative real-time RT-PCR. Comparison of the expression between healthy rats, SCI rats, and SCI treated with A-HOA rats revealed relevant changes in the expression of genes associated with neuronal morphogenesis and growth, neuronal survival, pain and inflammation. Thus, treatment with A-HOA not only induced a significant overexpression of growth and differentiation factor 10 (GDF10), tenascin C (TNC), aspirin (ASPN) and sushi-repeat-containing X-linked 2 (SRPX2), but also a significant reduction in the expression of prostaglandin E synthase (PTGES) and phospholipases A1 and A2 (PLA1/2). Currently, SCI has very important unmet clinical needs. A-HOA downregulated genes involved with inflammation and upregulated genes involved in neuronal growth, and may serve to promote recovery of function after experimental SCI.

Decrease of growth and differentiation factor 10 contributes to neuropathic pain through N-methyl-D-aspartate receptor activation.

Neuropathic pain is a chronic disease with hallmarks such as chronic allodynia and hyperalgesia. Previous studies have shown that the transforming growth factor-ß superfamily acts as a protecting factor against neuropathic pain. In the current study, we found that growth and differentiation factor 10 (GDF10), which belongs to the transforming growth factor-ß superfamily, is mainly expressed in the superficial layers of spinal dorsal horn neurons and it was dramatically downregulated after spinal nerve ligation and N-methyl-D-aspartate (NMDA) intrathecal infusion. Moreover, the decrease in GDF10 expression and increase in mechanical sensitivity could be blocked by MK-801, an antagonist of the NMDA receptor. These results suggest that the decreasing GDF10 may contribute toward neuropathic pain by facilitating NMDA receptor activation. Our findings shed new light on the understanding of the molecular mechanisms underlying neuropathic pain.

Overexpression of bone morphogenetic protein-3b (BMP-3b) in adipose tissues protects against high-fat diet-induced obesity.

BACKGROUND: Bone morphogenetic protein-3b (BMP-3b) is a member of the transforming growth factor-ß superfamily and has several activities that differ from those of other BMPs. We previously found that BMP-3b is highly expressed in adipocytes, its level is increased during obesity, and it inhibits adipogenesis by suppressing peroxisome proliferator-activated receptor γ (PPARγ) in vitro. However, the function of BMP-3b in adipose tissues in vivo remains unknown. METHODS: To determine the role of BMP-3b overexpression in adipose tissues in vivo, we generated transgenic mice (BMP-3b Tg) by using a conditional overexpression approach in fatty acid-binding protein 4-expressing adipocytes. We examined BMP-3b Tg mice fed a high-fat diet to elucidate the effects of BMP-3b on obesity. Adipocyte function was evaluated as expression of adipogenic and lipogenic markers in adipose tissue. We also performed glucose and insulin tolerance tests (GTT and ITT, respectively), and biochemical analysis of serum and measured energy expenditure by indirect calorimetry. RESULTS: BMP-3b Tg mice fed a high-fat diet showed decreases in weight gain, fat-pad mass and adipocyte area, compared with wild-type mice. The adipose tissues of BMP-3b Tg mice showed downregulated expression of PPARγ and its target gene encoding fatty acid translocase/CD36. In addition, BMP-3b Tg mice had decreased blood glucose levels on GTT and ITT, and their serum leptin levels were decreased and adiponectin concentrations were increased. These changes in BMP-3b Tg mice were accompanied by increased energy expenditure, indicated as increased locomotor activity and oxygen consumption. CONCLUSIONS: These results provide in vivo evidence that BMP-3b regulates adipocyte function to cause an anti-obesity effect.

The nuclear receptor REV-ERBα represses the transcription of growth/differentiation factor 10 and 15 genes in rat endometrium stromal cells.

Cellular oscillators in the uterus play critical roles in the gestation processes of mammals through entraining of the clock proteins to numerous downstream genes, including growth/differentiation factor (Gdf)10 and Gdf15. The expression of Gdf10 and Gdf15 is significantly increased in the uterus during decidualization, but the mechanism underlying the regulation of Gdf gene expression in the uterus is poorly understood. Here, we focused on the function of the cellular oscillators in the expression of Gdf family by using uterine endometrial stromal cells (UESCs) isolated from pregnant Per2-dLuc transgenic rats. A significant decline of Per2-dLuc bioluminescence activity was induced in in vitro decidualized UESCs, and concomitantly the expression of canonical clock genes was downregulated. Conversely, the expression of Gdf10 and Gdf15 of the Gdf was upregulated. In UESCs transfected with Bmal1-specific siRNA, in which Rev-erbα expression was downregulated, Gdf10 and Gdf15 were upregulated. However, Gdf5, Gdf7, and Gdf11 were not significantly affected by Bmal1 silencing. The expression of Gdf10 and Gdf15 was enhanced after treatment with a REV-ERBα antagonist in the presence or absence of progesterone. Chromatin immunoprecipitation-PCR analysis revealed the inhibitory effect of REV-ERBα on the expression of Gdf10 and Gdf15 in UESCs by recognizing their gene promoters. Collectively, our findings indicate that the attenuation of REV-ERBα leads to an upregulation of Gdf10 and Gdf15 in decidual cells, in which cellular oscillators are impaired. Our results provide novel evidence regarding the functions of cellular oscillators regulating the expression of downstream genes during the differentiation of UESCs.

Loss of GDF10/BMP3b as a prognostic marker collaborates with TGFBR3 to enhance chemotherapy resistance and epithelial-mesenchymal transition in oral squamous cell carcinoma.

Growth differentiation factor-10 (GDF10), commonly referred as BMP3b, is a member of the transforming growth factor-ß (TGF-ß) superfamily. GDF10/BMP3b has been considered as a tumor suppressor, however, little is known about the molecular mechanism of its roles in tumor suppression in oral cancer. Clinical significance of GDF10 downregulation in oral squamous cell carcinoma (OSCC) was evaluated using three independent cohorts of OSCC patients. The molecular mechanisms of GDF10 in the suppression of cell survival, cell migration/invasion and epithelial-mesenchymal transition (EMT) were investigated by using oral cancer cell lines. The present study shows that GDF10 is downregulated during oral carcinogenesis, and GDF10 expression is also an independent risk factor for overall survival of OSCC patients. Overexpression of GDF10 attenuates cell proliferation, transformation, migration/invasion, and EMT. GDF10-inhibited EMT is mediated by ERK signaling but not by typical TGF-ß signaling. In addition, overexpression of GDF10 promotes DNA damage-induced apoptosis and sensitizes the response to all-trans retinoic acid (ATRA) and camptothecin (CPT). Intriguingly, the expression of GDF10 is induced by type III TGF-ß receptor (TGFBR3) through TGF-ß-SMAD2/3 signaling. Our findings suggest that TGFBR3 is an upstream activator of GDF10 expression and they share the same signaling to inhibit EMT and migration/invasion. These results support that GDF10 acts as a hinge to collaborate with TGFBR3 in the transition of EMT-MET program. Taken together, we illustrated the clinical significance and the molecular mechanisms of tumor-suppressive GDF10 in OSCC.

Growth and differentiation factor 10 (Gdf10) is involved in Bergmann glial cell development under Shh regulation.

Growth differentiation factor 10 (Gdf10), also known as Bmp3b, is a member of the transforming growth factor (TGF)-ß superfamily. Gdf10 is expressed in Bergmann glial cells, which was investigated by single-cell transcriptional profiling (Koirala and Corfas, (2010) PLoS ONE 5: e9198). Here we provide a detailed characterization of Gdf10 expression from E14, the stage at which Gdf10 is expressed for the first time in the cerebellum, until P28. We detected Gdf10 expression in both germinal zones: in the ventricular zone (VZ) of the 4th ventricle as well as in the rhombic lip (RL). The VZ has been postulated to give rise to GABAergic neurons and glial cells, whereas the RL gives rise to glutamatergic neurons. Thus, it was very surprising to discover a gene that is expressed exclusively in glial cells and is not restricted to an expression in the VZ, but is also present in the RL. At postnatal stages Gdf10 was distributed equally in Bergmann glial cells of the cerebellum. Furthermore, we found Gdf10 to be regulated by Sonic hedgehog (Shh), which is secreted by Purkinje cells of the cerebellum. In the conditional Shh mutants, glial cells showed a reduced expression of Gdf10, whereas the expression of Nestin and Vimentin was unchanged. Thus, we show for the first time, that Gdf10, expressed in Bergmann glial cells, is affected by the loss of Shh as early as E18.5, suggesting a regulation of glial development by Shh.