Human telomerase reverse transcriptase (hTERT) plays a central role in telomere lengthening for continuous cell proliferation, but it remains unclear how extracellular cues regulate telomerase lengthening of telomeres. Here we report that the cytokine bone morphogenetic protein-7 (BMP7) induces the hTERT gene repression in a BMPRII receptor- and Smad3-dependent manner in human breast cancer cells. Chonic exposure of human breast cancer cells to BMP7 results in short telomeres, cell senescence and apoptosis. Mutation of the BMPRII receptor, but not TGFbRII, ACTRIIA or ACTRIIB receptor, inhibits BMP7-induced repression of the hTERT gene promoter activity, leading to increased telomerase activity, lengthened telomeres and continued cell proliferation. Expression of hTERT prevents BMP7-induced breast cancer cell senescence and apoptosis. Thus, our data suggest that BMP7 induces breast cancer cell aging by a mechanism involving BMPRII receptor- and Smad3-mediated repression of the hTERT gene.
Actin-Related Protein 2 ; genetics ; metabolism ; Activin Receptors, Type II ; genetics ; metabolism ; Bone Morphogenetic Protein 7 ; genetics ; metabolism ; Bone Morphogenetic Protein Receptors, Type II ; genetics ; metabolism ; Breast Neoplasms ; genetics ; metabolism ; Cellular Senescence ; Female ; HeLa Cells ; Humans ; MCF-7 Cells ; Neoplasm Proteins ; genetics ; metabolism ; Protein-Serine-Threonine Kinases ; genetics ; metabolism ; Receptor, Transforming Growth Factor-beta Type II ; Receptors, Transforming Growth Factor beta ; genetics ; metabolism ; Smad3 Protein ; genetics ; metabolism ; Telomerase ; genetics ; metabolism ; Telomere Homeostasis

OBJECTIVETo explore the mechanism of Bushen Qiangji Granule (, BSQJ) in restraining the osteogenic differentiation of ankylosing spondylitis (AS) fifibroblasts.

METHODSHip joint capsules were obtained from AS patients (n=10) receiving total hip replacement and healthy hip joint capsules from patients with hip fracture (n=10) receiving surgery as a control. Finite fifibroblast lines were established from these tissue samples to observe the effect of BSQJ on suppressing osteogenic differentiation of fifibroblasts. The expression of osteogenic marker gene corebinding factor a1 (Cbfa1) and Smad family proteins were examined by Western blot and real-time quantitative polymerase chain reaction (qPCR).

RESULTSThe mRNA expression level of Cbfa1 was significantly higher in AS fibroblasts than that in normal fibroblasts and the expression of pSmad1, pSmad5, Smad4 and Cbfa1 in AS fibroblasts was also higher, demonstrating the activation of the BMP/Smads signal pathway in AS fifibroblasts. BSQJ-medicated serum not only restrained the mRNA and protein expression levels of Cbfa1 and inhibited protein expression level of Smad4 but also decreased the expression quantities of pSmad1 and pSmad5.

CONCLUSIONSBSQJ can inhibit osteogenic differentiation of AS fifibroblasts in vitro by suppressing the activation of the BMP/Smads signal pathway. This may be the important molecular mechanism of BSQJ in regulating AS ossifification.

Adult ; Bone Morphogenetic Proteins ; metabolism ; Cell Differentiation ; drug effects ; Core Binding Factor Alpha 1 Subunit ; genetics ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Fibroblasts ; drug effects ; metabolism ; pathology ; Humans ; Middle Aged ; Osteogenesis ; drug effects ; genetics ; Phosphorylation ; drug effects ; RNA, Messenger ; genetics ; metabolism ; Serum ; metabolism ; Signal Transduction ; drug effects ; Smad Proteins ; metabolism ; Spondylitis, Ankylosing ; genetics ; pathology ; Young Adult

PURPOSE: This study is intended to investigate the effects of plants or plant-derived antioxidants on prevention of osteoporosis through the maintenance of reactive oxygen species (ROS) at a favorable level. MATERIALS AND METHODS: In this study, a novel antioxidant, namely 3,4,5-Trihydroxy-N-[4-(5-hydroxy-6-methoxy-pyrimidin-4-ylsulfamoyl)-phenyl]-benzamide (ZXHA-TC) was synthesized from gallic acid and sulfadimoxine. Its effect on osteoblast metabolism was investigated via the detection of cell proliferation, cell viability, production of ROS, and expression of osteogenic-specific genes including runt-related transcription factor 2 (RUNX2), bone sialoprotein (BSP), osteocalcin (OCN), alpha-1 type I collagen (COL1A1), and osteogenic-related proteins after treatment for 2, 4, and 6 days respectively. RESULTS: The results showed that ZXHA-TC has a stimulating effect on the proliferation and osteogenic differentiation of primary osteoblasts by promoting cell proliferation, cell viability, and the expression of genes BSP and OCN. Productions of bone matrix and mineralization were also increased by ZXHA-TC treatment as a result of up-regulation of COL1A1 and alkaline phosphatase (ALP) at the early stage and down-regulation of both genes subsequently. A range of 6.25x10(-3) microg/mL to 6.25x10(-1) microg/mL is the recommended dose for ZXHA-TC, within which 6.25x10(-2) microg/mL showed the best performance. CONCLUSION: This study may hold promise for the development of a novel agent for the treatment of osteoporosis.
Alkaline Phosphatase/metabolism ; Bone Morphogenetic Proteins/pharmacology ; Cell Differentiation/*drug effects ; Cell Proliferation/*drug effects ; Collagen Type I/genetics ; Core Binding Factor Alpha 1 Subunit ; Down-Regulation ; Gallic Acid ; Osteoblasts/*drug effects ; Osteocalcin/metabolism ; Osteogenesis/drug effects ; Osteoporosis/*prevention & control ; Reactive Oxygen Species ; Up-Regulation

OBJECTIVETo examine the transfection of Homeobox A13 (HOXA13) on epithelial-mesenchymal transition (EMT) and the expression of bone morphogenetic protein-7 (BMP-7) induced by albumin-overload in human kidney tubular epithelial cells (HKCs).

METHODSThe cultured HKCs were treated with 20 mg/mL human serum albumin (HSA) for 48 hours. Protein expression of cytokeratin (CK), vimentin and HOXA13 in the HKCs was assessed by Western blot. Protein expression of CK, vimentin, and BMP-7 was also detected in HKCs transfected with lipofectamine contained HOXA13 DNA.

RESULTSHSA induced EMT in HKCs, presented by decreased CK expression (P<0.01) and increased vimentin expression (P<0.01). The up-regulated expression of HOXA13 transfected by lipofectamine inhibited the level of EMT induced by HSA in HKCs (P<0.05). The decreased rate of BMP-7 protein expression induced by HSA was inhibited by over-expressed HOXA13 in HKCs (P<0.05).

CONCLUSIONSTransfection of HOXA13 in HKCs could inhibit the degree of EMT induced by albumin-overload, possibly by increasing BMP-7 expression.

Bone Morphogenetic Protein 7 ; genetics ; Cells, Cultured ; Epithelial Cells ; metabolism ; Epithelial-Mesenchymal Transition ; Homeodomain Proteins ; physiology ; Humans ; Keratins ; genetics ; Kidney Tubules ; metabolism ; Transfection ; Vimentin ; genetics

PURPOSE: To investigate the molecular responses of various genes and proteins related to disc degeneration upon treatment with cytokines that affect disc-cell proliferation and phenotype in living human intervertebral discs (IVDs). Responsiveness to these cytokines according to the degree of disc degeneration was also evaluated. MATERIALS AND METHODS: The disc specimens were classified into two groups: group 1 (6 patients) showed mild degeneration of IVDs and group 2 (6 patients) exhibited severe degeneration of IVDs. Gene expression was analyzed after treatment with four cytokines: recombinant human bone morphogenic protein (rhBMP-2), transforming growth factor-beta (TGF-beta), interleukin-1beta (IL-1beta), and tumor necrosis factor-alpha (TNF-alpha). Molecular responses were assessed after exposure of cells from the IVD specimens to these cytokines via real-time polymerase chain reaction and immunofluorescence staining. RESULTS: mRNA gene expression was significantly greater for aggrecan, type I collagen, type II collagen, alkaline phosphatase, osteocalcin, and Sox9 in group 1 than mRNA gene expression in group 2, when the samples were not treated with cytokines. Analysis of mRNA levels for these molecules after morphogen treatment revealed significant increases in both groups, which were much higher in group 1 than in group 2. The average number of IVD cells that were immunofluorescence stained positive for alkaline phosphatase increased after treatment with rhBMP-2 and TGF-beta in group 1. CONCLUSION: The biologic responsiveness to treatment of rhBMP-2, TGF-beta, TNF-alpha, and IL-1beta in the degenerative living human IVD can be different according to the degree of degeneration of the IVD.
Adult ; Aggrecans/genetics/metabolism ; Alkaline Phosphatase/genetics/metabolism ; Biological Products/pharmacology/*therapeutic use ; Bone Morphogenetic Protein 2/pharmacology/therapeutic use ; Collagen Type I/genetics/metabolism ; Collagen Type II/genetics/metabolism ; Cytokines/*pharmacology/*therapeutic use ; Female ; Fluorescent Antibody Technique ; Gene Expression Regulation/drug effects ; Humans ; Interleukin-1/pharmacology/therapeutic use ; Intervertebral Disc/*drug effects/*pathology ; Intervertebral Disc Degeneration/*drug therapy/genetics/*pathology ; Male ; Middle Aged ; Osteocalcin/genetics/metabolism ; RNA, Messenger/genetics/metabolism ; Recombinant Proteins/pharmacology/therapeutic use ; SOX9 Transcription Factor/genetics/metabolism ; Transforming Growth Factor beta/pharmacology/therapeutic use ; Tumor Necrosis Factor-alpha/pharmacology

Fucoidan has attracted attention as a potential drug because of its biological activities, which include osteogenesis. However, the molecular mechanisms involved in the osteogenic activity of fucoidan in human alveolar bone marrow-derived mesenchymal stem cells (hABM-MSCs) remain largely unknown. We investigated the action of fucoidan on osteoblast differentiation in hABM-MSCs and its impact on signaling pathways. Its effect on proliferation was determined using the crystal violet staining assay. Osteoblast differentiation was evaluated based on alkaline phosphatase (ALP) activity and the mRNA expression of multiple osteoblast markers. Calcium accumulation was determined by Alizarin red S staining. We found that fucoidan induced hABM-MSC proliferation. It also significantly increased ALP activity, calcium accumulation and the expression of osteoblast-specific genes, such as ALP, runt-related transcription factor 2, type I collagen-alpha 1 and osteocalcin. Moreover, fucoidan induced the expression of bone morphogenetic protein 2 (BMP2) and stimulated the activation of extracellular signal-related kinase (ERK), c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase by increasing phosphorylation. However, the effect of fucoidan on osteogenic differentiation was inhibited by specific inhibitors of ERK (PD98059) and JNK (SP600125) but not p38 (SB203580). Fucoidan enhanced BMP2 expression and Smad 1/5/8, ERK and JNK phosphorylation. Moreover, the effect of fucoidan on osteoblast differentiation was diminished by BMP2 knockdown. These results indicate that fucoidan induces osteoblast differentiation through BMP2-Smad 1/5/8 signaling by activating ERK and JNK, elucidating the molecular basis of the osteogenic effects of fucoidan in hABM-MSCs.
Bone Morphogenetic Protein 2/genetics/*metabolism ; Calcium/metabolism ; Cell Differentiation/drug effects ; Cell Proliferation/drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Extracellular Signal-Regulated MAP Kinases/*metabolism ; Gene Expression Regulation/drug effects ; Gene Knockdown Techniques ; Humans ; JNK Mitogen-Activated Protein Kinases/*metabolism ; Mesenchymal Stromal Cells/cytology/*drug effects/*metabolism ; Osteoblasts/cytology/drug effects/metabolism ; Osteogenesis/drug effects ; Phosphorylation ; Polysaccharides/*pharmacology ; Protein Kinase Inhibitors/pharmacology ; RNA, Messenger/genetics ; Signal Transduction/*drug effects ; Smad Proteins/*metabolism

OBJECTIVETo investigate the effect of compound Coptidis Rhizoma capsule (CCRC) on unbalanced expression of renal tissue TGF-β1/BMP-7 and Smad signaling pathway in rats with early diabetic nephropathy (DN), and discuss CCRC's effect on DN rats with early diabetic nephropathy and its possible mechanism.

METHODDN model rats were established by injecting streptozotocin (STZ). The rats were randomly divided into seven groups: the normal group, the model group, the enalapril treatment group, the xiaoke pill treatment group and three CRCC treatment groups. They were orally administered once a day for five weeks. The fasting blood glucose (FBG), blood urea nitrogen (BUN), serum creatinine (Scr), insulin (Ins), 24 h urinary protein (24 h Upro) and 24 h urinary microalbumin (24 h UmAlb) were tested. The pathological changes in renal tissues were examined by optical microscopy. Immuno- histochemical measures were used to detect the expressions of TGF-β1, BMP-7, Smad2/3, Smad1/5, and Smad7 protein, and RT-PCR was used to detect TGF-β1 mRNA and BMP-7 mRNA in renal tissues.

RESULTCompared with model group, BUN, Scr, Ins, 24 h Upro and 24 h UmAlb levels decreased at different degrees in CCRC treatment groups; the abnormal pathomorphology in renal tissue was improved; immunohistochemistry results showed that the expression of TGF-β1 and Smad2/3 were reduced, while the expression of BMP-7, Smad1/5 and Smad7 increased in CRCC treatment groups; the expression of TGF-β1 mRNA were reduced, but the expression of BMP-7 mRNA had no obvious change in CRCC treatment groups.

CONCLUSIONCRCC can improve the early renal function, delay the progression of chronic renal pathology and maintain the dynamic balance of TGF-β1/BMP-7 expression in renal tissues of DN rats. The mechanism may be related to down-regulation of renal TGF-β1 and up-regulation of BMP-7 through Smad signaling pathway.

Animals ; Bone Morphogenetic Protein 7 ; genetics ; metabolism ; Coptis ; chemistry ; Diabetic Nephropathies ; drug therapy ; genetics ; metabolism ; Gene Expression Regulation ; drug effects ; Humans ; Kidney ; drug effects ; metabolism ; Male ; Rats ; Rats, Sprague-Dawley ; Rhizome ; chemistry ; Signal Transduction ; drug effects ; Smad Proteins ; genetics ; metabolism ; Transforming Growth Factor beta1 ; metabolism

BACKGROUNDKeshan disease (KD) is an endemic cardiomyopathy in China. The etiology of KD is still under debate and there is no effective approach to preventing and curing this disease. Young women of child-bearing age are the most frequent victims in rural areas. The aim of this study was to determine the differences between molecular pathogenic mechanisms in male and female KD sufferers.

METHODSWe extracted RNA from the peripheral blood mononuclear cells of KD patients (12 women and 4 men) and controls (12 women and 4 men). Then the isolated RNA was amplified, labeled and hybridized to Agilent human 4×44k whole genome microarrays. Gene expression was examined using oligonucleotide microarray analysis. A quantitative polymerase chain reaction assay was also performed to validate our microarray results.

RESULTSAmong the genes differentially expressed in female KD patients we identified: HLA-DOA, HLA-DRA, and HLA-DQA1 associated with spontaneous autoimmunity; BMP5 and BMP7, involved in cardiomyocyte differentiation defect; and ADAMTS 8, CCL23, and TNFSF15, implicated in anti-angiogenic activities. These genes are involved in the canonical pathways and networks recognized for the female KD sufferers and might be related to the pathogenic mechanism of KD.

CONCLUSIONOur results might help to explain the higher susceptibility of women to this disease.

ADAM Proteins ; genetics ; ADAMTS Proteins ; Adult ; Autoimmunity ; genetics ; physiology ; Bone Morphogenetic Protein 5 ; genetics ; Bone Morphogenetic Protein 7 ; genetics ; Cardiomyopathies ; genetics ; pathology ; Cell Differentiation ; genetics ; physiology ; Chemokines, CC ; genetics ; Enterovirus Infections ; genetics ; pathology ; Female ; Gene Expression Profiling ; HLA-D Antigens ; genetics ; HLA-DQ alpha-Chains ; genetics ; HLA-DR alpha-Chains ; genetics ; Humans ; Male ; Middle Aged ; Myocytes, Cardiac ; cytology ; metabolism ; Oligonucleotide Array Sequence Analysis ; Sex Factors ; Tumor Necrosis Factor Ligand Superfamily Member 15 ; genetics

OBJECTIVETo construct a luciferase reporter vector containing the response element of transcription protein AP2α for screening the effect of bone morphogenetic proteins (BMPs) on the transcriptional activity of AP2α.

METHODSFour tandem-linked response elements of AP2α were cloned to the pBGLuc luciferase reporter gene plasmid, which was digested with Bam HI and Mlu I to construct pBGLuc-AP2α-RE vector. The recombinant adenovirus Ad-AP2α and its dominant negative mutant Ad-dnAP2α were used to infect mouse mesenchymal stem cells C3H10; the changes in cellular AP2α mRNA and protein expressions were detected by real-time PCR and Western blotting, and electrophoretic mobility shift assay (EMSA) was carried out to assess the DNA-binding ability of AP2α. C3H10 cells were transfected with pBGLuc-AP2α-RE vector, and AP2α transcriptional activity was measured using luciferase reporter gene assay. In pBGLuc-AP2α-RE vector-transfected C3H10 cells infected with Ad-BMPs, luciferase reporter gene assay was performed to screen the effect of BMPs on AP2α transcriptional activity.

RESULTSThe results of PCR, enzyme digestion and sequencing all confirmed correct cloning of AP2α-RE into pBGLuc-AP2α-RE luciferase reporter vector, and Ad-AP2α infection significantly increased AP2α expression and its DNA binding ability. The dominant negative mutants expressed the corresponding mutants, and EMSA results showed that Ad-dnAP2α-δbHLH significantly lowered while Ad-dnAP2α-δTAD enhanced the DNA-binding ability of AP2α. AP2α over-expression promoted AP2α transcriptional activity, which was suppressed by the two dominant negative mutants. AP2α transcriptional activity increased in the cells infected with the recombinant adenovirus BMPs, especially in cells with BMP9 infection.

CONCLUSIONSThe luciferase reporter vector containing the response element of AP2α we constructed allows detection of AP2α transcriptional activity. BMP9 can significantly enhance AP2α transcriptional activity.

Adenoviridae ; Animals ; Bone Morphogenetic Proteins ; genetics ; metabolism ; Genes, Reporter ; Genetic Vectors ; Growth Differentiation Factor 2 ; genetics ; metabolism ; Luciferases ; genetics ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Mice ; Osteogenesis ; Protein Binding ; RNA, Messenger ; metabolism ; Recombinant Proteins ; genetics ; metabolism ; Response Elements ; Transcription Factor AP-2 ; genetics ; metabolism ; Transcriptional Activation ; Transfection

BACKGROUNDAlthough various systemic and local factors such as abnormal carbohydrate or calcium metabolism, aging, and hormonal disturbances have been suggested as causes of ossification of the posterior longitudinal ligament (OPLL), the etiology of OPLL is not fully understood. The purpose of this study was to investigate whether bone morphogenetic protein (BMP)-2 is a candidate gene to modify the susceptibility of OPLL and the mechanism of signal transduction in ossification.

METHODSA total of 420 OPLL patients and 506 age- and sex-matched controls were studied. The complete coding sequence of the human BMP-2 gene was analyzed using polymerase chain reaction (PCR) and direct sequencing. All single nucleotide polymorphisms (SNPs) were detected and genotyped. BMP-2 expression vectors containing positive polymorphisms were constructed and transfected into the C3H10T1/2 cells. The expression of BMP-2 and the Smad signal pathway in positive cell clones were detected by Western blotting. The alkaline phosphatase (ALP) activity was determined using quantitative detection kits.

RESULTSThe frequencies for the 109T > G and 570A > T polymorphisms were different between the case and control groups. The "TG" genotype in 109T > G polymorphism is associated with the occurrence of OPLL, the frequency of the "G" allele is significantly higher in patients with OPLL than in control subjects (P < 0.001). The "AT" genotype in 570A > T polymorphism is associated with the occurrence of OPLL, the frequency of the "T" allele is significantly higher in patients with OPLL than in control subjects (P = 0.005). Western blotting analysis revealed that the expression of P-Smad1/5/8 protein transfected by wild-type or mutant expression vectors were significantly higher than control groups (P < 0.05), but there was no statistical difference in each experimental group (P > 0.05). The expression of Smad4 protein transfected by wild-type or mutant expression vectors was significantly higher than control groups (P < 0.05). The expression of Smad4 protein transfected by pcDNA3.1-BMP2 (109G) and pcDNA3.1-BMP2 (109G, 570T) was significantly higher than the other experimental groups (P < 0.05). The increase in ALP activity has been detected in pcDNA3.1-BMP2 (109G) and pcDNA3.1-BMP2 (109G, 570T) transfected cells up to 4 weeks after stable transfection. Activity of ALP was (30.56 ± 0.46) nmol×min(-1)×mg(-1) protein and (29.62 ± 0.68) nmol×min(-1)×mg(-1) protein, respectively. This was statistically different compared with the other experimental groups (P < 0.05).

CONCLUSIONSBMP-2 is the predisposing gene of OPLL. The "TG" genotype in the 109T > G and the "AT" genotype in the 570A > T polymorphisms are associated with the occurrence of OPLL. The 109T > G polymorphism in exon-2 of the BMP-2 gene is positively associated with the level of Smad4 protein expression and the activity of ALP. The Smad mediated signaling pathway plays an important role during the pathological process of OPLL induced by SNPs of BMP-2 gene.

Adult ; Aged ; Bone Morphogenetic Protein 2 ; genetics ; Cells, Cultured ; Female ; Humans ; In Situ Hybridization ; Longitudinal Ligaments ; metabolism ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; genetics ; Signal Transduction ; genetics ; physiology ; Smad Proteins ; metabolism ; Spine ; metabolism