The seat of human intelligence is the human cerebral cortex, which is responsible for our exceptional cognitive abilities. Identifying principles that lead to the development of the large-sized human cerebral cortex will shed light on what makes the human brain and species so special. The remarkable increase in the number of human cortical pyramidal neurons and the size of the human cerebral cortex is mainly because human cortical radial glial cells, primary neural stem cells in the cortex, generate cortical pyramidal neurons for more than 130 days, whereas the same process takes only about 7 days in mice. The molecular mechanisms underlying this difference are largely unknown. Here, we found that bone morphogenic protein 7 (BMP7) is expressed by increasing the number of cortical radial glial cells during mammalian evolution (mouse, ferret, monkey, and human). BMP7 expression in cortical radial glial cells promotes neurogenesis, inhibits gliogenesis, and thereby increases the length of the neurogenic period, whereas Sonic Hedgehog (SHH) signaling promotes cortical gliogenesis. We demonstrate that BMP7 signaling and SHH signaling mutually inhibit each other through regulation of GLI3 repressor formation. We propose that BMP7 drives the evolutionary expansion of the mammalian cortex by increasing the length of the neurogenic period.
Animals ; Mice ; Humans ; Ependymoglial Cells/metabolism* ; Hedgehog Proteins/metabolism* ; Ferrets/metabolism* ; Cerebral Cortex ; Neurogenesis ; Mammals/metabolism* ; Neuroglia/metabolism* ; Bone Morphogenetic Protein 7/metabolism*

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 the protective effects of Panax notoginseng saponins (PNS) on kidney in diabetic rats.

METHODSDiabetic rat model was obtained by intravenous injection of alloxan, and the rats were divided into model, PNS-100 mg/(kg day) and PNS-200 mg/(kg day) groups, 10 each. Another 10 rats injected with saline were served as control. Periodic acid-Schiff staining and immunological histological chemistry were used to observe histomorphology and tissue expression of bone morphogenetic protein-7 (BMP-7). Silent information regulator 1 (SIRT1) was silenced in rat mesangial cells by RNA interference. The mRNA expressions of SIRT-1, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor β1 (TGF-β1) and plasminogen activator inhibitor-1 (PAI-1) were analyzed by reverse transcription polymerase chain reaction. The protein expressions of SIRT1 and the acetylation of nuclear factor κB (NF-κB) P65 were determined by western blotting. The concentration of MCP-1, TGF-β1 and malondialdehyde (MDA) in culture supernatant were detected by enzyme-linked immuno sorbent assay. The activity of superoxide dismutase (SOD) was detected by the classical method of nitrogen and blue four.

RESULTSIn diabetic model rats, PNS could not only reduce blood glucose and lipid (P<0.01), but also increase protein level of BMP-7 and inhibit PAI-1 expression for suppressing fibrosis of the kidney. In rat mesangial cells, PNS could up-regulate the expression of SIRT1 (P<0.01) and in turn suppress the transcription of TGF-β1 (P<0.05) and MCP-1 (P<0.05). PNS could also reverse the increased acetylation of NF-κB p65 by high glucose. In addition, redox regulation factor MDA was down-regulated (P<0.05) and SOD was up-regulated (P<0.01), which were both induced by SIRT1 up-regulation.

CONCLUSIONSPNS could protect kidney from diabetes with the possible mechanism of up-regulating SIRT1, therefore inhibiting inflammation through decreasing the induction of inflammatory cytokines and TGF-β1, as well as activating antioxidant proteins.

Acetylation ; drug effects ; Animals ; Antioxidants ; metabolism ; Blood Glucose ; metabolism ; Bone Morphogenetic Protein 7 ; metabolism ; Chemokine CCL2 ; metabolism ; Diabetes Mellitus, Experimental ; blood ; drug therapy ; genetics ; physiopathology ; Gene Knockdown Techniques ; Immunohistochemistry ; Kidney ; drug effects ; pathology ; Kidney Function Tests ; Lipids ; blood ; Male ; Malondialdehyde ; metabolism ; Mesangial Cells ; drug effects ; metabolism ; Oxidative Stress ; drug effects ; Panax notoginseng ; chemistry ; Plasminogen Activator Inhibitor 1 ; genetics ; metabolism ; Protective Agents ; pharmacology ; therapeutic use ; Rats, Sprague-Dawley ; Saponins ; pharmacology ; therapeutic use ; Sirtuin 1 ; genetics ; Superoxide Dismutase ; metabolism ; Transcription Factor RelA ; metabolism ; Transcription, Genetic ; drug effects ; Transforming Growth Factor beta1 ; metabolism ; Up-Regulation ; drug effects

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

OBJECTIVETo obtain highly efficient small interfering RNAs (siRNAs) against bone morphogenetic protein-7 (BMP-7) for future functional analysis of BMP-7 in bone homeostasis.

METHODSWe designed 4 independent siRNA sequences against rat BMP-7 and transfected them in rat umbilical vein endothelial cells. After 72 h, we examined BMP-7 mRNA and protein level in the transfected cells using real-time PCR and Western blotting, respectively.

RESULTSAll the 4 siRNAs effectively reduced BMP-7 expression in rat umbilical vein endothelial cells, and among them BMP-7-3 siRNA showed the highest efficiency.

CONCLUSIONWe have obtained an efficient siRNA to knockdown BMP-7 expression in vitro for further investigation of the role of BMP-7 in bone and cartilage formation.

Animals ; Bone Morphogenetic Protein 7 ; genetics ; metabolism ; Cells, Cultured ; Endothelial Cells ; metabolism ; RNA, Messenger ; RNA, Small Interfering ; Rats ; Real-Time Polymerase Chain Reaction ; Transfection

OBJECTIVETo investigate the differentiation capability of kidney stem cells (KSCs) into renal tubular epithelial cells (RTECs).

METHODSKSCs isolated from the renal papilla of 4-week-old SD rats were co-cultured with hypoxia-exposed RTEC in induced medium (containing activin A, BMP-7, and retinoic acid) and renal epithelial cell growth medium (REGM) alternately. The KSCs cultured in MSC medium served as the control. The KSC differentiation rates in both groups were determined using flow cytometry, immunofluorescence assay and qRT-PCR.

RESULTSFlow cytometry showed a CK-18 positive rate of 6.5Percnt; in the control KSC group and of 44.2% in the induced group. Immunofluorescence assay detected the positivity for mature epithelial cell markers CK-18, E-cadherin, and ZO-1 in the induced cells. The results of qRT-PCR showed significantly increased expression of E-cadherin and AQP-1 mRNAs in the induced cells compared with the control cells (P<0.01).

CONCLUSIONRat KSCs can be induced to differentiate into RTECs in vitro.

Activins ; chemistry ; Animals ; Aquaporin 1 ; metabolism ; Bone Morphogenetic Protein 7 ; chemistry ; Cadherins ; metabolism ; Cell Differentiation ; Coculture Techniques ; Culture Media ; chemistry ; Epithelial Cells ; cytology ; Keratin-18 ; metabolism ; Kidney Tubules ; cytology ; Rats ; Rats, Sprague-Dawley ; Stem Cells ; cytology ; Tretinoin ; chemistry ; Zonula Occludens-1 Protein ; metabolism

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

OBJECTIVETo evaluate the effect of bone morphogenetic protein(BMP7)on the differentiation of adipose derived mesenchymal stem cells(AD-MSCs)isolated from different adipose tissues into brown adipocytes in rats.

METHODSPrimary AD-MSCs were isolated from rate interscapular brown adipose tissue(iBAT),inguinal subcutaneous white adipose tissue(sWAT),and epididymal white adipose tissue(eWAT),respectively,and then cultivated in vitro. Differentiation of AD-MSCs into brown adipocytes was induced by BMP7. The characteristics of brown adipocytes were detected by immunofluorescence staining and oil red staining of cells. The expression levels of brown adipocyte-related genes were detected by polymerase chain reaction.

RESULTSAD-MSCs from iBAT and sWAT were differentiated into cluster multilocular cells,which were stained red by oil red "O"staining and showed uncoupling protein 1-positive by immunofluorescent staining method. AD-MSCs from eWAT had a small number of scattered multilocular cells and showed uncoupling protein 1-negative. The results of reverse transcription-polymerase chain reaction showed that the uncoupling protein 1 gene was highly expressed in the iBAT group and sWAT group but was negative in the eWAT group.

CONCLUSIONAD-MSCs isolated from different adipose tissues in rats have different gene expression profiles and differentiation potentials.

Adipocytes, Brown ; physiology ; Adipose Tissue ; metabolism ; Adipose Tissue, Brown ; physiology ; Animals ; Bone Morphogenetic Protein 7 ; metabolism ; Cell Differentiation ; physiology ; Ion Channels ; metabolism ; Mesenchymal Stromal Cells ; physiology ; Mitochondrial Proteins ; metabolism ; Obesity ; metabolism ; Rats ; Uncoupling Protein 1

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

OBJECTIVEThis study explored the dynamic expression of the E3 ubiquitin-protein ligase gene, Arkadia, in response to carbon tetrachloride (CCl4)-induced liver fibrosis in a mouse model and investigated the differential expression that occurs following treatment with the anti-fibrotic bone morphogenetic protein-7 (BMP-7).

METHODSThirty healthy male imprinting control region (ICR) mice were randomly assigned to three groups: normal (control; n = 6), CCl4-induced model group (model; n = 18), and CCl4-induced model with BMP-7 treatment group (treatment; n = 6). The model group was further divided into three subgroups (n = 6 each) for analysis at 4, 8 and 12 weeks after fibrosis induction. Liver fibrosis was induced by hypodermic injections of 60% CCl4 /peanut oil (5 mL/kg) to the hind legs of mice two-times per week in alternating legs for a period of 12 weeks. At week 9, the treatment group of CCl4-induced mice were given an intraperitoneal injection of BMP-7 (300 pg/g) simultaneously with that day's hypodermic injection of 60% CCl4 /peanut oil, and then every other day for a period of four weeks. The pathological changes in liver tissues were observed after staining with hematoxylin-eosin (HE) and Masson's trichrome. Messenger RNA (mRNA) and protein expression of Arkadia in liver were evaluated using reverse transcription-polymerase chain reaction and immunohistochemistry and Western blotting, respectively.

RESULTSMouse models of liver fibrosis were successfully established by CCl4 exposure. Arkadia, Smad7 and TGF-beta1 mRNA levels were up-regulated in the model group in a time-dependent manner (vs. control group), and BMP-7 treatment led to significant down-regulation of the CCl4-induced expression of the three genes (vs. control group: F = 812.80, 451.46, and 998.96, respectively; P less than 0.01). At week 12, the mRNA levels of Arkadia, Smad7, and TGF-b1 were significantly lower in the BMP-7 treatment group than in the model group (t = 12.108, 18.737, and 16.364, respectively; P less than 0.01). Arkadia, Smad7, and TGF-b1 protein staining was weak in the portal area of control liver tissue. In contrast, the model group showed significantly stronger staining for all three proteins in the portal area and in the cytoplasm of liver cells. The staining of Arkadia, Smad7, and TGF-b1 proteins was significantly lower in the treatment group (vs. control group: F = 8.399, 609.690, and 900.561, respectively; P < 0.01). At week 12, the protein levels of Arkadia, Smad7, and TGF-b1 were significantly lower in the treatment group than in the model group (t = 23.438, 11.667, and 42.889, respectively; P < 0.01).

CONCLUSIONArkadia expression gradually increased along with the development of liver fibrosis but was suppressed by treatment with the anti-fibrotic factor, BMP-7.

Animals ; Bone Morphogenetic Protein 7 ; pharmacology ; Liver ; metabolism ; Liver Cirrhosis, Experimental ; metabolism ; prevention & control ; Male ; Mice ; Mice, Inbred ICR ; Ubiquitin-Protein Ligases ; metabolism ; Up-Regulation