Docta Complutense
Open Access Institutional Repository of the Complutense University of Madrid, that compiles scientific production to promote the visibility and impact of Complutense research.
With the collaboration of the Ministerio de Ciencia e Innovación and the Spanish Foundation for Science and Technology (FECYT).
Recent Submissions
Osteoprotective effects of the neuropeptide VIP: insights from triple cultures of human osteocytes, osteoblasts, and osteoclasts
(Traslational Research, 2026) Castro Vázquez, David; García López, Ivan; Wirsig, Katharina; Arribas Castaño, Paula; Pérez Gomáriz, Rosa María; Martínez Mora, María Del Carmen; Juarranz Moratilla, Yasmina; Bernhardt, Anne; Carrión Caballo, Mar
Bone remodelling is a dynamic process of osteoblastic bone formation and osteoclastic bone resorption, regulated by local, paracrine and endocrine factors, in which osteocytes act as orchestrators of bone homeostasis. Among these regulatory factors, the neuropeptide VIP (vasoactive intestinal peptide) has demonstrated osteoprotective effects by inhibiting osteoclastogenesis and promoting osteoblast differentiation. However, its potential role in osteocyte biology remains unexplored. In this study, we investigated the effect of VIP on the differentiation of primary human osteocytes. We describe for the first time the expression of VIP and its receptors during in vitro osteocyte differentiation. Our results show that VIP promotes osteocytogenesis, accompanied by a reduction in the RANKL/OPG ratio, thereby supporting its role as an anti-osteoclastogenic factor. To better mimic the complexity of bone tissue, we performed triple co-cultures of osteoblasts and simultaneously differentiating osteocytes and osteoclasts, in the presence or absence of VIP. Our results confirmed that VIP supports the osteoblast-to-osteocyte transition and promotes an osteoprotective phenotype, characterized by a reduced RANKL/OPG ratio and decreased SOST expression. The downregulation of sclerostin may attenuate osteocyte-mediated inhibitory signalling toward osteoblasts and, in turn, contribute to the reduction of the osteoblastic RANKL/OPG ratio. Collectively, our findings reinforce the anti-osteoclastogenic actions of VIP, supporting its role as a potential osteoprotective factor.
From terrestrialisation to disturbance: long-term trajectories of a fen ecosystem and its conservation implications in the Xistral Mountains, NW Iberia
(Biodiversity and Conservation, 2026) Hernando Bartolomé, Álvaro; Moreno Martín, Álvaro; Magaña Ugarte, Rosina; Manzano, Saúl; Martínez Cortizas, Antonio; López Merino, Lourdes
Peatlands in north-west Iberia are globally important carbon reservoirs, yet their fen communities remain less well understood than those of bogs. Here, we present a multiproxy study of a ~11,100 cal. yr BP peat sequence cored at the Toxiza fen (TOX, Xistral Mountains, Galicia). Our analyses of palynology, rarefaction, charcoal, elemental composition and CIELab colour identify three main ecological phases. First, early Holocene mire initiation through terrestrialisation: wet meadows progressively replaced by a transitional fen at ~10,350 cal. yr BP, and subsequently by a Sphagnum-rich fen. Second, the mire experienced a prolonged phase of hydrological stability during the Holocene Climatic Optimum, characterised by Sphagnum-rich vegetation, high organic-matter content and sustained peat accumulation. Third, late Holocene increasing disturbance, including catchment erosion (~4900-4200 cal. yr BP) and fire-intense phases leading to an Ericaceae-rich fen; with Sphagnum partially recovered in reduced-burning intervals. Phases of ecological transition (i.e., early Holocene terrestrialisation and late Holocene disturbance) showed higher pollen richness, whereas comparatively stable values were found during the mid-Holocene, reflecting long-term ecosystem stability. Comparisons with nearby ombrotrophic mires highlight the importance of hydrological setting (minerotrophy vs. ombrotrophy) in shaping peatland vegetation trajectories under similar climatic forcing. Today the fen shows clear signs of degradation, including fire activity, sediment inputs and afforestation pressure, with no clear Sphagnum recovery. The TOX record, therefore, provides a process-based reference baseline for conservation where the mid-Holocene Sphagnum-rich phase represents a benchmark of hydrological stability and minimal disturbance, offering a framework for understanding biodiversity change and for guiding restoration of minerotrophic peatlands under ongoing environmental change.
Harvested by
