Person: Martínez Álvarez, María Concepción
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First Name
María Concepción
Last Name
Martínez Álvarez
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Odontología
Department
Area
Anatomía y Embriología Humana
Identifiers
4 results
Search Results
Now showing 1 - 4 of 4
Item Occurrence of cleft-palate and alteration of Tgf-β3 expression and the mechanisms leading to palatal fusion in mice following dietary folic-acid deficiency(Cells Tissues Organs, 2011) Maldonado Bautista, Estela; Murillo González, Jorge Alfonso; Barrio Asensio, María Del Carmen; Río Sevilla, Aurora Del; Pérez De Miguelsanz, María Juliana; López Gordillo, Yamila; Partearroyo, Teresa; Paradas Lara, Irene; Maestro De Las Casas, María Del Carmen; Martínez Sanz, Elena; Varela Moreiras, Gregorio; Martínez Álvarez, María ConcepciónFolic acid (FA) is essential for numerous bodily functions. Its decrease during pregnancy has been associated with an increased risk of congenital malformations in the progeny. The relationship between FA deficiency and the appearance of cleft palate (CP) is controversial, and little information exists on a possible effect of FA on palate development. We investigated the effect of a 2–8 weeks’ induced FA deficiency in female mice on the development of CP in their progeny as well as the mechanisms leading to palatal fusion, i.e. cell proliferation, cell death, and palatal-shelf adhesion and fusion. We showed that an 8 weeks’ maternal FA deficiency caused complete CP in the fetuses although a 2 weeks’ maternal FA deficiency was enough to alter all the mechanisms analyzed. Since transforming growth factor beta 3 (TGF-β3) is crucial for palatal fusion and since most of the mechanisms impaired by FA deficiency were also observed in the palates of Tgf-β3 null mutant mice, we investigated the presence of TGF-beta 3 mRNA, its protein and phospho-SMAD2 in FA-deficient (FAD) mouse palates. Our results evidenced a large reduction in Tgf-β3 expression in palates of embryos of dams fed an FAD diet for 8 weeks; Tgf-β3 expression was less reduced in palates of embryos of dams fed an FAD diet for 2 weeks. Addition of Tgf-β3 to palatal-shelf cultures of embryos of dams fed an FAD diet for 2 weeks normalized all the altered mechanisms. Thus, an insufficient folate status may be a risk factor for the development of CP in mice, and exogenous Tgf-β3 compensates this deficit in vitro.Item Analysis of the presence of cell proliferation-related molecules in the Tgf-β3 null mutant mouse palate reveals misexpression of EGF and Msx-1(Cells Tissues Organs, 2011) Del Río, A; López-Gordillo, Y; Martínez, M L; Barrio Asensio, María Del Carmen; Murillo Arroyo, Francisco Javier; Maldonado Bautista, Estela; Martínez Sanz, Elena; Martínez Álvarez, María ConcepciónThe Tgf-β3 null mutant mouse palate presents several cellular anomalies that lead to the appearance of cleft palate. One of them concerns the cell proliferation of both the palatal medial edge epithelium and mesenchyme. In this work, our aim was to determine whether there was any variation in the presence/distribution of several cell proliferation-related molecules that could be responsible for the cell proliferation defects observed in these palates. Our results showed no difference in the presence of EGF-R, PDGF-A, TGF-β2, Bmp-2, and Bmp-4, and differences were minimal for FGF-10 and Shh. However, the expression of EGF and Msx-1 changed substantially. The shift of the EGF protein expression was the one that most correlated with that of cell proliferation. This molecule is regulated by TGF-β3, and experiments blocking its activity in culture suggest that EGF misexpression in the Tgf-β3 null mutant mouse palate plays a role in the cell proliferation defect observed.Item Craniofacial structure alterations of foetuses from folic acid deficient pregnant mice(Annals of Anatomy, 2018) López, Yamila; Martínez-Sanz, Eelena; Maldonado Bautista, Estela; Herrera Lara, Manuel Eugenio; Martínez Álvarez, María Concepción; Pérez De Miguelsanz, María JulianaIntroduction: Craniofacial development in mammals is a complex process that involves a coordinated series of molecular and morphogenetic events. Folic acid (FA) deficiency has historically been associated with congenital spinal cord malformations, but the effect that a maternal diet deficient in FA has on the development of other structures has been poorly explored. In the present study, the objective was to describe and quantify the alterations of craniofacial structures presented in mouse foetuses from dams fed a FA deficient (FAD) diet compared with controls that were given a regular maternal diet. Material and methods: E17 mouse foetuses were removed from dams that were fed with a control diet or with a FAD diet for several weeks. Foetuses with maternal FAD diets were selected for the study when they showed an altered tongue or mandible. Histological sections were used to quantify the dimensions of the head, tongue, mandibular bone and masseter muscle areas using ImageJ software. The muscles of the tongue, suprahyoid muscles, lingual septum, submandibular ducts, and lingual arteries were also analysed. Results: The heads of malformed foetuses were smaller than the heads of the controls, and they showed different types of malformations: microglossia with micrognathia (some of which were combined with cleft palate) and aglossia with either micrognathia or agnathia. Lingual and suprahyoid muscles were affected in different forms and degrees. We also found alterations in the lingual arteries and in the ducts of the submandibular glands. Summarised we can state that pharyngeal arches-derived structures were affected, and the main malformations observed corroborate the vulnerability of cranial neural crest cells to FA deficiency. Conclusion: The present study reveals alterations in the development of craniofacial structures in FAD foetuses. This study provides a new focus for the role of FA during embryological development.Item Transforming Growth Factor-β3 Regulates Adipocyte Number in Subcutaneous White Adipose Tissue(CELL REPORTS, 2017) Petrus, Paul et al.; Rydén M.; Maldonado Bautista, Estela; Martínez Álvarez, María ConcepciónWhite adipose tissue (WAT) mass is determined by adipocyte size and number. While adipocytes are continuously turned over, the mechanisms controlling fat cell number in WAT upon weight changes are unclear. Herein, prospective studies of human subcutaneous WAT demonstrate that weight gain increases both adipocyte size and number, but the latter remains unaltered after weight loss. Transcriptome analyses associate changes in adipocyte number with the expression of 79 genes. This gene set is enriched for growth factors, out of which one, transforming growth factor-b3 (TGFb3), stimulates adipocyte progenitor proliferation, resulting in a higher number of cells undergoing differentiation in vitro. The relevance of these observations was corroborated in vivo where Tgfb3+/ mice, in comparison with wild-type littermates, display lower subcutaneous adipocyte progenitor proliferation, WAT hypertrophy, and glucose intolerance. TGFb3 is therefore a regulator of subcutaneous adipocyte number and may link WAT morphology to glucose metabolism.