No / Hair pigmentation is controlled by tightly coordinated programs of melanin synthesis and involves signaling through the melanocortin type 1 receptor (MC-1R) that regulates the switch between pheomelanogenesis and eumelanogenesis. However, the involvement of other signaling systems, including the bone morphogenetic protein (BMP) pathway, in the control of hair pigmentation remains to be elucidated. To assess the effects of BMP signaling on hair pigmentation, transgenic mice overexpressing the BMP antagonist noggin (promoter: keratin 5) were generated. Whereas wild-type C3H/HeJ mice have a subapical yellow band on otherwise black dorsal hairs, K5-Noggin mice are characterized by the absence of a yellow band and near-black pigment in dorsal coat. Noggin overexpression is accompanied by strongly reduced levels of Agouti signal protein and enhanced expression of microphthalmia transcription factor in the midphase of the hair-growth cycle. Wild-type color in K5-Noggin mice is restored by administration of a synthetic MC-1R antagonist resulting in the reappearance of a subapical yellow band. BMP-4 stimulates the expression of Agouti transcripts and protein in primary epidermal keratinocytes, and BMP signaling positively regulates dermal papilla-specific enhancer of the Agouti gene in primary dermal fibroblasts. Taken together, these data suggests that BMP signaling controls the expression of Agouti protein in the hair follicle and provide evidence for interaction between BMP and MC-1R signaling pathways to modulate the balance between pheomelanogenesis and eumelanogenesis during hair growth.

The role of cytokines and cell behavior and viability with respect to bone remodeling and bone behavior is an exciting area of orthopedic research. The purpose of this study was to investigate the relationships between BMP antagonist expression and osteocyte density, lacunar densities and osteocyte viability in cortical bone. Samples of unloaded tibial bone obtained from six C57Bl/6 mice were immunohistochemically stained for gremlin and noggin expression and also underwent methyl green staining to determine osteocyte presence. Bone sections were divided into four quadrants (cranial, caudal, medial and lateral) and three regions (proximal, mid shaft and distal), followed by analysis across these quadrants and regions. The results showed matching regional differences in gremlin expression with regional variations in osteocyte density, lacunar density, and osteocyte viability. These variations were supported by positive correlations found via regression analysis. Regression analysis also showed marginal negative correlations between noggin expression and osteocyte density and osteocyte viability, supported by regional ANOVA results. Further research on loaded bone samples is needed if the relationship between these BMP antagonists and osteocyte densities are to be fully explained with respect to the bone remodeling process.

Bone morphogenetic proteins (BMPs) and their receptors (BMPRs) coordinate tissue development and postnatal remodelling by regulating proliferation, differentiation and apoptosis. However, their role in wound healing remains unclear. To study this, transgenic mice overexpressing Smad1 (K14-caSmad1) or the BMP antagonist Noggin (K14-Noggin) were utilised, together with human and mouse ex vivo wound healing models and in vitro keratinocyte culture. In wild-type mice, transcripts for Bmpr-1A, Bmpr-II, Bmp ligands and Smad proteins were decreased following tissue injury, whilst Bmpr-1B expression was up-regulated. Furthermore, immunohistochemistry revealed a down-regulation of BMPR-1A in hair follicles adjacent to the wound in murine skin, whilst in murine and human wounds, BMPR-1B and phospho-Smad-1/5/8 expression was pronounced in the wound epithelial tongue. K14-caSmad1 mice displayed retarded wound healing, associated with reduced keratinocyte proliferation and increased apoptosis, whilst K14-Noggin mice exhibited accelerated wound healing. Furthermore, microarray analysis of K14-caSmad1 epidermis revealed decreased expression of distinct cytoskeletal and cell motility-associated genes including wound-associated keratins (Krt16, Krt17) and Myo5a versus controls. Human and mouse keratinocyte proliferation and migration were suppressed by BMP-4/7 both in vitro and ex vivo, whilst they were stimulated by Noggin. Additionally, K14-caSmad1 keratinocytes showed retarded migration compared to controls when studied in vitro. Furthermore, Bmpr-1B silencing accelerated migration and was associated with increased expression of Krt16, Krt17 and Myo5a versus controls. Thus, this study demonstrates that BMPs inhibit proliferation, migration and cytoskeletal re-organization in epidermal keratinocytes during wound healing, and raises a possibility that BMP antagonists may be used for the future management of chronic wounds.

No / Bone morphogenetic protein (BMP) signaling is involved in the regulation of a large variety of developmental programs, including those controlling organ sizes. Here, we show that transgenic (TG) mice overexpressing the BMP antagonist noggin (promoter, K5) are characterized by a marked increase in size of anagen hair follicles (HFs) and by the replacement of zig-zag and auchen hairs by awl-like hairs, compared with the age-matched WT controls. Markedly enlarged anagen HFs of TG mice show increased proliferation in the matrix and an increased number of hair cortex and medulla cells compared with WT HFs. Microarray and real-time PCR analyses of the laser-captured hair matrix cells show a strong decrease in expression of Cdk inhibitor p27(Kip1) and increased expression of selected cyclins in TG vs. WT mice. Similar to TG mice, p27(Kip1) knockout mice also show an increased size of anagen HFs associated with increased cell proliferation in the hair bulb. Primary epidermal keratinocytes (KC) from TG mice exhibit significantly increased proliferation and decreased p27(Kip1) expression, compared with WT KC. Alternatively, activation of BMP signaling in HaCaT KC induces growth arrest, stimulates p27(Kip1) expression, and positively regulates p27(Kip1) promoter activity, thus further supporting a role of p27(Kip1) in mediating the effects of BMP signaling on HF size. These data suggest that BMP signaling plays an important role in regulating cell proliferation and controls the size of anagen HFs by modulating the expression of cell-cycle-associated genes in hair matrix KC.

<p>Proper morphogenesis is essential for both form and function of mammalian craniofacial and neural tube development. Craniofacial deformities and neural tube defects are highly prevalent human birth defects. Although studies concerning craniofacial and neural tube development have revealed important genetic and/or environmental factors, understanding the mechanisms underlying proper development and the defects remain incomplete. </p><p>Among many genes that were cloned as the gastrula organizer genes in 1990s, Nog, a secreted BMP antagonist, is expressed in the relevant domains during craniofacial and neural tube development. Previous studies show that Nog null embryos exhibit fully penetrant spina bifida (open spine) and to the lesser extent exencephaly (open brain). Moreover, Nog null mice display deformities in skeletal structures including defects in craniofacial skeleton. As such, Nog is essential for proper neural tube and craniofacial development. However, it is still not clear that which domain(s) of Nog are responsible for proper craniofacial development or neural tube closure. In addition, it is also an important question when, and in what capacity Nog is necessary during development of craniofacial and neural tube.</p> / Dissertation

Bone morphogenetic proteins (BMPs) and their receptors (BMPRs) coordinate tissue development and postnatal remodelling by regulating proliferation, differentiation and apoptosis. However, their role in wound healing remains unclear. To study this, transgenic mice overexpressing Smad1 (K14-caSmad1) or the BMP antagonist Noggin (K14-Noggin) were utilised, together with human and mouse ex vivo wound healing models and in vitro keratinocyte culture. In wild-type mice, transcripts for Bmpr-1A, Bmpr-II, Bmp ligands and Smad proteins were decreased following tissue injury, whilst Bmpr-1B expression was up-regulated. Furthermore, immunohistochemistry revealed a down-regulation of BMPR-1A in hair follicles adjacent to the wound in murine skin, whilst in murine and human wounds, BMPR-1B and phospho-Smad-1/5/8 expression was pronounced in the wound epithelial tongue. K14-caSmad1 mice displayed retarded wound healing, associated with reduced keratinocyte proliferation and increased apoptosis, whilst K14-Noggin mice exhibited accelerated wound healing. Furthermore, microarray analysis of K14-caSmad1 epidermis revealed decreased expression of distinct cytoskeletal and cell motility-associated genes including wound-associated keratins (Krt16, Krt17) and Myo5a versus controls. Human and mouse keratinocyte proliferation and migration were suppressed by BMP-4/7 both in vitro and ex vivo, whilst they were stimulated by Noggin. Additionally, K14-caSmad1 keratinocytes showed retarded migration compared to controls when studied in vitro. Furthermore, Bmpr-1B silencing accelerated migration and was associated with increased expression of Krt16, Krt17 and Myo5a versus controls. Thus, this study demonstrates that BMPs inhibit proliferation, migration and cytoskeletal re-organization in epidermal keratinocytes during wound healing, and raises a possibility that BMP antagonists may be used for the future management of chronic wounds.

The osteogenic effects of bone morphogenetic protein-2 (BMP-2) on human mesenchymal stem cells (MSCs) are less profound than expected as compared with rodent cells, and supraphysiological dose of BMP-2 is required to achieve desired clinical outcome. The mechanism for this phenomenon is unclear. In this study, we examined the effects of macrophages and noggin suppression on the BMP-2-induced osteogenesis of human bone marrow MSCs in vitro. Our data show that macrophage conditioned medium significantly decreased the migration capacity, metabolic activity and BMP-2-induced osteogenesis of MSCs. In addition, knocking down noggin by small interfering RNA (siRNA) also significantly decreased BMP-2-induced osteogenesis and proliferation of MSCs. In summary, our studies demonstrated that macrophages and knocking down the expression of noggin decreased BMP-2-induced osteogenesis of human MSCs in vitro. In the future, manipulation on macrophage activation and noggin expression may allow us to achieve higher BMP-2-induced osteogenesis that leads to better bone healing. / Experimental Surgery

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Made available in DSpace on 2014-12-17T15:32:33Z (GMT). No. of bitstreams: 1 CyntiaHPC_TESE.pdf: 1535929 bytes, checksum: 7d7c8298def3233365b9ad5eb617d015 (MD5) Previous issue date: 2014-02-27 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy in the oral cavity and reach a large number of individuals, has become an important public health problem. Studies have demonstrated changes in pathway components BMP in various types of cancers as prostate, colon, breast, gastric and OSCCs. Is the current knowledge that these proteins may exert pro-tumor effect in more advanced stages of neoplastic development coming to favor progression and invasion tumor. The inhibition of the signaling pathway BMP-2 through its antagonists, have shown positive results of antitumor activity and use of Noggin may be a novel therapeutic target for cancer. Given this evidence and the few studies with BMP-2, Noggin and OSCC, the objective of this research was to evaluate the effect of BMP-2 and its antagonist Noggin on proliferation and migration cell in line of cell cultures of human tongue squamous cell carcinoma (SCC25). The study was divided in three groups, a control group, where SCC25 cells suffered no treatment, a BMP-2 group, in which cells were treated with 100ng/ml of BMP-2 and a group of cells that were treated with 100ng/ml of Noggin. For the proliferation assay and cell cycle were established three time intervals (24, 48 and 72 hours). Proliferative activity was investigated by trypan blue and cell cycle analysis by staining with propidium iodide flow cytometry. The potential for migration / invasion of SCC25 cells was performing by a cell invasion assay using Matrigel in a 48-hour interval. The proliferation curve showed a higher proliferation in cells treated with BMP-2 in 72 hours (p < 0.05), and lower overgrowth and cell viability in Noggin group. Recombinant proteins favored a greater percentage of cells in cell cycle phase Go/G1 with a statistically significant difference in the interval of 24 hours (p < 0.05). BMP- 2 produced a greater invasion of cells studied as well as its antagonist Noggin inhibits invasion of cells (p < 0.05). Thus, these results indicate that BMP-2 promotes malignant phenotype, dues stimulates proliferation and invasion of SCC25 cells and, its antagonist Noggin may be an alternative treatment, due to inhibit the tumor progression / O carcinoma epiderm?ide oral (CEO) representa a neoplasia maligna mais prevalente na cavidade oral e por atingir um grande n?mero de indiv?duos, acaba se tornado um relevante problema de sa?de p?blica. Muitos estudos demonstram altera??es nos componentes da via BMP em v?rios tipos de tumores, como os de pr?stata, c?lon, mama, g?stricos e CEOs. ? do conhecimento atual que essas prote?nas podem exercer efeito pr?-tumoral em est?gios mais avan?ados do desenvolvimento neopl?sico vindo a favorecer a progress?o e invas?o tumoral. A inibi??o da via de sinaliza??o da BMP-2, atrav?s dos seus antagonistas, tem mostrado resultados positivos de a??o antitumoral e que assim, o uso do Noggin pode ser um novo alvo terap?utico contra o c?ncer. Diante destas evid?ncias e dos escassos trabalhos com BMP-2, Noggin e CEO, o objetivo desta pesquisa foi avaliar o efeito da BMP-2 e seu antagonista Noggin sobre a prolifera??o e migra??o celulares em culturas de c?lulas de carcinoma epiderm?ide de l?ngua humana (SCC25). Foi feita a divis?o em tr?s grupos de estudo, um grupo controle, onde as c?lulas SCC25 n?o sofriam tratamento com subst?ncia alguma, um grupo BMP-2, no qual as c?lulas eram tratadas com 100ng/ml de BMP-2 e um grupo de c?lulas que eram tratadas com 100ng/ml de Noggin. Para o ensaio de prolifera??o e ciclo celular foram estabelecidos tr?s intervalos de tempo (24, 48 e 72 horas). A atividade proliferativa foi investigada por azul de tripan e a an?lise do ciclo celular atrav?s da marca??o por iodeto de prop?dio em Citometria de fluxo. O potencial de migra??o/invas?o das c?lulas SCC25 foi avaliado atrav?s da realiza??o de um ensaio de invas?o celular utilizando o matrigel em um intervalo de 48 horas. A curva de prolifera??o revelou maior crescimento celular nas c?lulas tratadas com BMP-2 no intervalo de 72 horas (p<0.05) e menor crecimento e viabilidade celular no grupo Noggin. As prote?nas recombinantes favoreceram a maior porcentagem das c?lulas na fase do ciclo celular Go/G1 com diferen?a estatisticamente significativa no intervalo de 24 horas (p<0,05). A BMP-2 promoveu uma maior invas?o das c?lulas estudadas, assim como o seu antagonista Noggin inibiu a invas?o das c?lulas estudadas (p<0,05). Dessa forma, os resultados indicam que a BMP-2 favorece o fen?tipo maligno, pois estimula a prolifera??o e invas?o das c?lulas SCC25 e seu antagonista Noggin pode ser uma alternativa terap?utica pois inibiu essas caracter?sticas pr?-tumorais

Bone morphogenetic protein (BMP) signalling plays key roles in skin development and also possesses a potent anti-tumour activity in postnatal skin. To study mechanisms of the tumour-suppressive role of BMPs in the skin, a transgenic (TG) mouse model was utilized, in which a transgenic expression of the BMP antagonist Noggin was targeted to the epidermis and hair follicles (HFs) via Keratin 14 promoter. K14-Noggin mice developed spontaneous HF-derived tumours, which resembled human trichofolliculoma. Initiation of the tumours was associated with a marked increase in cell proliferation and an expansion of the hair follicle stem/early progenitor cells. In addition, the TG mice showed hyperplastic changes in the sebaceous glands and the interfollicular epidermis. The epidermal hyperplasia was associated with an increase in the susceptibility to chemically-induced carcinogenesis and earlier malignant transformation of chemically-induced papillomas. Global gene expression profiling revealed that development of the trichofolliculomas was associated with an increase in the expression of the components of several pro-oncogenic signalling pathways (Wnt, Shh, PDGF, Ras, etc.). Specifically, expression of the Wnt ligands and (β-catenin/Lef1) markedly increased at the initiation stage of tumour formation. In contrast, expression of components of the Shh pathway was markedly increased in the fully developed tumours, compared to the tumour placodes. Pharmacological treatment of the TG mice with the Wnt and Shh antagonists resulted in the stage-dependent inhibition of the tumour initiation and progression, respectively. Further studies revealed that BMP signalling antagonizes the activity of the Wnt and Shh pathways via distinct mechanisms, which include direct regulation of the expression of the tumour suppressor Wnt inhibitory factor 1 (Wif1) and indirect effects on the Shh expression. Thus, tumour suppressor activity of the BMPs in skin epithelium depends on the local concentrations of Noggin and is mediated, at least in part, via stage-dependent antagonizing of the Wnt and Shh signalling pathways.