http://hdl.handle.net/10366/3958 2026-05-03T21:18:07Z 2026-05-03T21:18:07Z Tur González, Raquel Abad Hernández, María Mar Filipovich, Elena Rivas, María Belén Rodríguez González, Marta Montero González, Juan Carlos Sayagués Manzano, José María http://hdl.handle.net/10366/168906 2026-02-20T11:19:59Z 2025-01-01T00:00:00Z

[EN]BACKGROUND Colorectal cancer (CRC) is the second leading cause of cancer-related death, largely due to limited treatment options in advanced stages. Genomic alterations in advanced CRC (aCRC) are complex and not fully characterized, with only 30% of patients benefiting from targeted therapies. AIM To investigate the molecular heterogeneity of primary aCRC in order to identify clinically relevant genomic alterations. METHODS We conducted a retrospective molecular analysis of 73 consecutive patients with histologically confirmed primary aCRC (stage pT4a-b). All molecular findings were correlated with available clinicopathological data. In addition, we performed survival analyses using publicly available datasets and tools. RESULTS Genetic abnormalities identified in primary tumors were most frequently mutations in tumor protein p53 (58% of cases), Kirsten rat sarcoma viral oncogene homolog (52%), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (25%), B-Raf kinase (11%) and fibroblast growth factor receptor 3 (8%), as well as R-spondin 3 (RSPO3) fusions (8%). Alterations in the tumor protein p53 and neuroblastoma RAS viral oncogene homolog genes were predominantly observed in tumors from the left colon, whereas B-Raf kinase mutations and RSPO3 fusions were more frequently detected in the right or transverse colon. We also show a strong association between the presence of RSPO3 rearrangements and patients with small tumors, normal carcinoembryonic antigen levels, and microsatellite stable tumors. Furthermore, aCRC patients with protein tyrosine phosphatase receptor type k::RSPO3 fusions exhibited a higher mortality rate. Elevated RSPO3 gene expression levels were also significantly correlated with poorer OS across two large, independent CRC cohorts. CONCLUSION This study identifies a relatively high incidence of RSPO3 rearrangements in aCRC and a strong association with clinical features. Furthermore, we find that RSPO3 fusions are associated with poorer OS. Tur R, Abad M, Filipovich E, Rivas MB, Rodriguez M, Montero JC, Sayagués JM. RSPO3 rearrangements in advanced colorectal cancer patients and their relationship with disease characteristics. World J Gastrointest Oncol 2025; 17(11): 112838 [PMID: 41281482 DOI: 10.4251/wjgo.v17.i11.112838]

2025-01-01T00:00:00Z Sayagués Manzano, José María Montero González, Juan Carlos Jiménez Pérez, Andrea Carmen Martínez, Sofía del Rodríguez González, Marta Vidal Tocino, María del Rosario Montero, Enrique Sanz, Julia Abad Hernández, María Mar http://hdl.handle.net/10366/168861 2026-02-19T12:33:30Z 2023-01-01T00:00:00Z

[EN]Sporadic colorectal cancer (sCRC) initially presents as metastatic tumors in 25–30% of patients. The 5-year overall survival (OS) in patients with metastatic sCRC is 50%, falling to 10% in patients presenting with synchronous metastatic disease (stage IV). In this study, we systematically analyzed the mutations of RAS, PIK3CA and BRAF genes in circulating tumor DNA (ctDNA) and tumoral tissue DNA (ttDNA) from 51 synchronous metastatic colorectal carcinoma (SMCC) patients by real-time PCR, and their relationship with the clinical, biological and histological features of disease at diagnosis. The highest frequency of mutations detected was in the KRAS gene, in tumor biopsies and plasma samples, followed by mutations of the PIK3CA, NRAS and BRAF genes. Overall, plasma systematically contained those genetic abnormalities observed in the tumor biopsy sample from the same subject, the largest discrepancies detected between the tumor biopsy and plasma from the same patient being for mutations in the KRAS and PIK3CA genes, with concordances of genotyping results between ttDNA and ctDNA at diagnosis of 75% and 84%, respectively. Of the 51 SMCC patients in the study, 25 (49%) showed mutations in at least 1 of the 4 genes analyzed in patient plasma. From the prognostic point of view, the presence and number of the most common mutations in the RAS, PIK3CA and BRAF genes in plasma from SMCC patients are independent prognostic factors for OS. Determination of the mutational status of ctDNA in SMCC could be a key tool for the clinical management of patients.

2023-01-01T00:00:00Z Montero González, Juan Carlos Carmen Martínez, Sofía del Abad Hernández, María Mar Sayagués Manzano, José María Barbáchano, Antonio Fernández Barral, Asunción Muñoz, Alberto Pandiella Alonso, Atanasio http://hdl.handle.net/10366/168849 2026-01-16T01:02:16Z 2023-01-01T00:00:00Z

[EN]Advanced colorectal cancer (CRC) is difficult to treat. For that reason, the development of novel therapeutics is necessary. Here we describe a potentially actionable plasma membrane target, the amino acid transporter protein subunit CD98hc. Western blot and immunohistochemical analyses of CD98hc protein expression were carried out on paired normal and tumoral tissues from patients with CRC. Immunofluorescence and western studies were used to characterize the action of a DM1-based CD98hc-directed antibody–drug conjugate (ADC). MTT and Annexin V studies were performed to evaluate the effect of the anti-CD98hc-ADC on cell proliferation and apoptosis. CRISPR/Cas9 and shRNA were used to explore the specificity of the ADC. In vitro analyses of the antitumoral activity of the anti-CD98hc-ADC on 3D patient-derived normal as well as tumoral organoids were also carried out. Xenografted CRC cells and a PDX were used to analyze the antitumoral properties of the anti-CD98hc-ADC. Genomic as well proteomic analyses of paired normal and tumoral samples showed that CD98hc expression was significantly higher in tumoral tissues as compared to levels of CD98hc present in the normal colonic tissue. In human CRC cell lines, an ADC that recognized the CD98hc ectodomain, reached the lysosomes and exerted potent antitumoral activity. The specificity of the CD98hc-directed ADC was demonstrated using CRC cells in which CD98hc was decreased by shRNA or deleted using CRISPR/Cas9. Studies in patient-derived organoids verified the antitumoral action of the anti-CD98hc-ADC, which largely spared normal tissue-derived colon organoids. In vivo studies using xenografted CRC cells or patient-derived xenografts confirmed the antitumoral activity of the anti-CD98hc-ADC. The studies herewith reported indicate that CD98hc may represent a novel ADC target that, upon welldesigned clinical trials, could be used to increase the therapeutic armamentarium against CRC.

2023-01-01T00:00:00Z Sanchón Sánchez, Paula Briz Sánchez, Oscar Rodríguez Macías, Rocío Isabel Abad Hernández, María Mar Sánchez Martín, Anabel García Marín, José Juan Lozano Esteban, Elisa http://hdl.handle.net/10366/168847 2026-01-16T10:35:13Z 2023-01-01T00:00:00Z

[EN]Cholangiocarcinoma (CCA) is a highly lethal cancer originated in the biliary tree. Available treatments for CCA are scarcely effective, partly due to mechanisms of chemoresistance, such as aberrant activation of Wnt/β-catenin pathway and dysfunctional p53. To evaluate the impact of enhancing the expression of negative regulators of the Wnt/β-catenin pathway (AXIN1, AXIN2, and GSK3B) and the tumor suppressor gene TP53. Gene expression in paired samples of CCA and adjacent non-tumor liver tissue was determined by RT-qPCR and immunohistochemistry (IHC). Using lentiviral vectors, CCA cells were transduced with genes of interest to assess their impact on the resistome (TLDA), apoptosis (annexin V/propidium iodide), and decreased cell viability (MTT). IHC revealed marked nuclear localization of β-catenin, consistent with Wnt/β-catenin pathway activation. In silico analysis with data from TCGA showed heterogeneous down-regulation of AXIN1, AXIN2, and GSK3B in CCA. Enhancing the expression of AXIN1, AXIN2, and GSK3B in CCA cells was not enough to block the activity of this signaling pathway or significantly modify resistance to 5-FU, gemcitabine, and platinated drugs. Consistent with impaired p53 function, CDKN1A was down-regulated in CCA. Forced TP53 expression induced p21 up-regulation and reduced cell proliferation. Moreover, the resistome was modified (FAS, BAX, TYMP, and CES2 up-regulation along with DHFR, RRM1, and BIRC5 down-regulation), which was accompanied by enhanced sensitivity to some antitumor drugs, mainly platinated drugs. Enhancing TP53 expression, but not that of AXIN1, AXIN2, and GSK3B, in CCA cells may be a useful strategy to sensitize CCA to antitumor drugs.

2023-01-01T00:00:00Z Montero González, Juan Carlos Calvo Jiménez, Elisa Carmen Martínez, Sofía del Abad Hernández, María Mar Ocaña, Alberto Pandiella Alonso, Atanasio http://hdl.handle.net/10366/168827 2026-02-23T08:58:53Z 2022-01-01T00:00:00Z

[EN]Background: Despite the incorporation of novel therapeutics, advanced triple negative breast cancer (TNBC) still represents a relevant clinical problem. Considering this, as well as the clinical efficacy of antibody-drug conjugates (ADCs), we aimed at identifying novel ADC targets that could be used to treat TNBC. Methods: Transcriptomic analyses were performed on TNBC and normal samples from three different studies. Plasma membrane proteins of three cell lines representative of the TNBC subtype were identified by cell surface biotinyla‑ tion or plasma membrane isolation, followed by analyses of cell surface proteins using the Surfaceome online tool. Immunofluorescence and western studies were used to characterize the action of a CD98hc-directed ADC, which was prepared by in house coupling of emtansine to an antibody that recognized the ectodomain of CD98hc. Xenografted TNBC cells were used to analyze the antitumoral properties of the anti-CD98hc ADC. Results: Comparative genomic studies between normal breast and TNBC tissues, together with proteomic and bioin‑ formatic analyses resulted in the elaboration of a catalog of potential ADC targets. One of them, the CD98hc trans‑ membrane protein, was validated as an ADC target. An antibody recognizing the ectodomain of CD98hc efficiently internalized and reached the lysosomal compartment. An emtansine-based ADC derived from such antibody was prepared and showed antitumoral properties in TNBC in vitro and in vivo models. Mechanistically, the anti-CD98hc ADC blocked cell cycle progression, that was followed by cell death caused by mitotic catastrophe. Conclusions: This work describes a list of potential ADC targets in TNBC and validates one of them, the transmem‑ brane protein CD98hc. The studies presented here also demonstrate the robustness of the multiomic approach herewith described to identify novel potential ADC targets.

2022-01-01T00:00:00Z Santos Ledo, Adrián Washer, Sam Dhanaseelan, Tamil Eley, Lorraine Alqatani, Ahlam Chrystal, Paul W Papoutsi, Tania Henderson, Deborah J Chaudhry, Bill Chrystal, Paul W. Henderson, Deborah J. http://hdl.handle.net/10366/167616 2026-02-20T10:44:47Z 2020-05-01T00:00:00Z

[EN]The planar cell polarity pathway is required for heart development and whilst the functions of most pathway members are known, the roles of the jnk genes in cardiac morphogenesis remain unknown as mouse mutants exhibit functional redundancy, with early embryonic lethality of compound mutants. In this study zebrafish were used to overcome early embryonic lethality in mouse models and establish the requirement for Jnk in heart development. Whole mount in-situ hybridisation and RT-PCR demonstrated that evolutionarily conserved alternative spliced jnk1a and jnk1b transcripts were expressed in the early developing heart. Maternal zygotic null mutant zebrafish lines for jnk1a and jnk1b, generated using CRISPR-Cas9, revealed a requirement for jnk1a in formation of the proximal, first heart field (FHF)-derived portion of the cardiac ventricular chamber. Rescue of the jnk1a mutant cardiac phenotype was only possible by injection of the jnk1a EX7 Lg alternatively spliced transcript. Analysis of mutants indicated that there was a reduction in the size of the hand2 expression field in jnk1a mutants which led to a specific reduction in FHF ventricular cardiomyocytes within the anterior lateral plate mesoderm. Moreover, the jnk1a mutant ventricular defect could be rescued by injection of hand2 mRNA. This study reveals a novel and critical requirement for Jnk1 in heart development and highlights the importance of alternative splicing in vertebrate cardiac morphogenesis. Genetic pathways functioning through jnk1 may be important in human heart malformations with left ventricular hypoplasia.

2020-05-01T00:00:00Z Gómez Martínez, Mario Rincón Iglesias, Héctor Gómez Álvarez, Marcelo Gómez Nieto, Ricardo José Saldaña Fernández, Enrique http://hdl.handle.net/10366/167499 2026-03-19T09:33:55Z 2025-03-01T00:00:00Z

[EN]Animals integrate auditory and somatosensory stimuli because the perception of sounds depends not only on their position relative to the sound source, but also on the posture of the head and ears. In the mammalian brain, audiotactile integration already occurs in the dorsal cochlear nucleus (DCN), a very early station of the central auditory pathway. In the DCN, auditory inputs preferentially target the deep layer, whereas somatosensory inputs innervate granule cells, whose axons target the superficial, molecular layer. However, there is an often overlooked major pathway that presumably conveys direct auditory information to the molecular layer of the DCN: the projection from the contralateral ventral nucleus of the trapezoid body (VNTB), first characterized by Warr and Beck (1996, Hear. Res., 93:83-101). To investigate in detail the morphology and distribution of the VNTB-to-DCN projection, we injected the bidirectional tracer biotinylated dextran amine (BDA) into the VNTB of adult rats and analyzed the axons that innervate the DCN. Moreover, to identify the neurons that innervate the DCN, we injected BDA into the DCN and analyzed the retrogradely labeled VNTB neurons. Our results show that the VNTB-to-DCN projection is very predominantly contralateral. The axons reach the cochlear nuclei via the rostral part of the trapezoid body. Within the DCN, VNTB axons form a very dense plexus that covers the entire molecular layer and, to a lesser extent, the underlying fusiform cell layer. These axons bear a high number of en passant and terminal synaptic boutons. In the plexus, parasagittal bands of higher density perpendicular to the pial surface alternate with bands of lower density. The VNTB-to-DCN projection is tonotopic. The DCN is innervated by medium-sized multipolar neurons that occupy the ventral two-thirds of the VNTB and are distributed throughout the rostrocaudal extent of the nucleus. Moreover, the deep layer of the DCN is innervated by the ipsilateral lateral nucleus of the trapezoid body. Although the biological role of the VNTB-to-DCN projection remains unknown, the available evidence from the literature suggests that it is GABAergic. Given its density, the projection may be very relevant to the functions of the DCN. Therefore, this projection should be considered in future investigations of DCN physiology and pathology, and should be incorporated into future morphofunctional schemes and models of the DCN.

2025-03-01T00:00:00Z García Macia, Marina Santos Ledo, Adrián Caballero, Beatriz Rubio-González, Adrian de Luxán-Delgado, Beatriz Potes, Yaiza Rodríguez-González, Susana Mª. Boga, José Antonio Coto-Montes, Ana http://hdl.handle.net/10366/161912 2026-02-20T10:47:58Z 2019-01-01T00:00:00Z

[EN]Sexual dimorphism has been reported in many processes. However, sexual bias in favour of the use of males is very present in science. One of the main reasons is that the impact of hormones in diverse pathways and processes such as autophagy have not been properly addressed in vivo. The Harderian gland is a perfect model to study autophagic modulation as it exhibits important changes during the oestrous cycle. The aim of this study is to identify the main processes behind Harderian gland differences under oestrous cycle and their modulator. In the present study we show that redox-sensitive transcription factors have an essential role: NF-κB may activate SQSTM1/p62 in oestrus, promoting selective types of autophagy: mitophagy and lipophagy. Nrf2 activation in dioestrus, leads the retrieval phase and restoration of mitochondrial homeostasis. Melatonin’s receptors show higher expression in dioestrus, leading to decreases in pro-inflammatory mediators and enhanced Nrf2 expression. Consequently, autophagy is blocked, and porphyrin release is reduced. All these results point to melatonin as one of the main modulators of the changes in autophagy during the oestrous cycle.

2019-01-01T00:00:00Z Santos Ledo, Adrián García Macia, Marina Campbell, Philip D. Gronska, Marta Marlow, Florence L. Campbell, Philip D. Marlow, Florence L http://hdl.handle.net/10366/161911 2026-02-20T10:48:53Z 2017-01-01T00:00:00Z

[EN]During skeletal morphogenesis diverse mechanisms are used to support bone formation. This can be seen in the bones that require a cartilage template for their development. In mammals the cartilage template is removed, but in zebrafish the cartilage template persists and the bone mineralizes around the cartilage scaffold. Remodeling of unmineralized cartilage occurs via planar cell polarity (PCP) mediated cell rearrangements that contribute to lengthening of elements; however, the mechanisms that maintain the chondrocyte template that supports perichondral ossification remain unclear. We report double mutants disrupting two zebrafish kinesin-I genes (hereafter kif5Blof) that we generated using CRISPR/Cas9 mutagenesis. We show that zygotic Kif5Bs have a conserved function in maintaining muscle integrity, and are required for cartilage remodeling and maintenance during craniofacial morphogenesis by a PCP-distinct mechanism. Further, kif5Blof does not activate ER stress response genes, but instead disrupts lysosomal function, matrix secretion, and causes deregulated autophagic markers and eventual chondrocyte apoptosis. Ultrastructural and transplantation analysis reveal neighboring cells engulfing extruded kif5Blof chondrocytes. Initial cartilage specification is intact; however, during remodeling, kif5Blof chondrocytes die and the cartilage matrix devoid of hypertrophic chondrocytes remains and impedes normal ossification. Chimeric and mosaic analyses indicate that Kif5B functions cell-autonomously in secretion, nuclear position, cell elongation and maintenance of hypertrophic chondrocytes. Interestingly, large groups of wild-type cells can support elongation of neighboring mutant cells. Finally, mosaic expression of kif5Ba, but not kif5Aa in cartilage rescues the chondrocyte phenotype, further supporting a specific requirement for Kif5B. Cumulatively, we show essential Kif5B functions in promoting cartilage remodeling and chondrocyte maintenance during zebrafish craniofacial morphogenesis.

2017-01-01T00:00:00Z Carreño Gutierrez , Héctor Santos Ledo, Adrián Velasco Arranz, María Almudena Lara Pradas, Juan Manuel Aijón Noguera, José Arévalo Arévalo, María Rosario http://hdl.handle.net/10366/161910 2025-04-30T19:24:21Z 2013-01-01T00:00:00Z

[EN]Retinoic acid (RA) is an important morphogen involved in retinal development. Perturbations in its levels cause retinal malformations such as microphthalmia. However, the cellular changes in the retina that lead to this phenotype are little known. We have used the zebrafish to analyse the effects of systemic high RA levels on retinogenesis. For this purpose we exposed zebrafish embryos to 0.1μM or 1μM RA from 24 to 48h post-fertilisation (hpf), the period which corresponds to the time of retinal neurogenesis and initial retinal cell differentiation. We did not find severe alterations in 0.1μM RA treated animals, but the exposure to 1μM RA significantly reduced retinal size upon treatment, and this microphthalmia persisted through larval development. We monitored histology and cell death and quantified both the proliferation rate and cell differentiation from 48hpf onwards, focusing on the retina and optic nerve of normal and 1μM treated animals. Retinal lamination and initial neurogenesis are not affected by RA exposure, but we found widespread apoptosis after RA treatment that could be the main cause of microphthalmia. Proliferating cells increased their number at 3days post-fertilisation (dpf) but decreased significantly at 5dpf maintaining the microphthalmic phenotype. Retinal cell differentiation was affected; some cell markers do not reach normal levels at larval stages and some cell types present an increased number compared to those of control animals. We also found the presence of young axons growing ectopically within the retina. Moreover although the optic axons leave the retina and form the optic chiasm they do not reach the optic tectum. The alterations observed in treated animals become more severe as larvae develop.

2013-01-01T00:00:00Z Santos Ledo, Adrián Arenzana, F.J. Porteros Herrero, Ángel Fernando Lara Pradas, Juan Manuel Velasco Arranz, María Almudena Aijón Noguera, José Arévalo Arévalo, María Rosario http://hdl.handle.net/10366/161909 2026-02-19T12:49:40Z 2011-01-01T00:00:00Z

[EN]Embryonic exposure to ethanol leads to malformations such as cyclopia. Cyclopic embryos present fused eyes and lack of the ventral specification of the brain, with physiological and morphological defects in the visual system, which provides a useful model for teratology and neurotoxicity assessments. We analysed the differentiation of the visual areas in the ethanol-induced cyclopic animals. For this purpose we exposed zebrafish embryos to 1.5% ethanol from 4 hours post-fertilisation (hpf) to 24 hpf in order to get cyclopic embryos. We monitored cytoarchitecture and quantified both the proliferation rate and cell differentiation from 2 days post-fertilisation (dpf) onwards, focusing on the main components of the visual system (retina, optic nerve and optic tectum) of normal and cyclopic zebrafish embryos. The visual system of the zebrafish embryos is affected by exposure to ethanol; two optic nerves that fuse before leaving the eyes are present in cyclopic specimens but an optic chiasm is not evident. Cell differentiation is severely delayed throughout the visual system at 2 dpf. At 5 dpf, lamination in the cyclopic retina and optic tectum is completed, but they are filled with pyknotic nuclei demonstrating cell death. At this stage the proliferation rate and expression patterns are unaltered and glial and neuronal neurochemical differentiations are similar to untreated animals. We found that the alterations produced by exposure to ethanol are not only cell-selective, but also tissue-selective. Cyclopia is the most severe phenotype induced by ethanol, although cell differentiation and proliferation can reach normal patterns after a certain period of time, which points to a neural plasticity process. Zebrafish embryos may possess a compensation mechanism against the ethanol effect, which would account for their use for pharmacogenetic and chemical screenings in the analysis of new molecules that could improve visual problems.

2011-01-01T00:00:00Z Santos Ledo, Adrián Cavodeassi, F. Carreño, H. Aijón, J. Arévalo, R. http://hdl.handle.net/10366/161867 2026-02-20T10:52:47Z 2013-01-01T00:00:00Z

[EN]Ethanol has been described as a teratogen in vertebrate development. During early stages of brain formation, ethanol affects the evagination of the optic vesicles, resulting in synophthalmia or cyclopia, phenotypes where the optic vesicles partially or totally fuse. The mechanisms by which ethanol affects the morphogenesis of the optic vesicles are however largely unknown. In this study we make use of in situ hybridization, electron microscopy and immunohistochemistry to show that ethanol has profound effects on cell organization and gene expression during the evagination of the optic vesicles. Exposure to ethanol during early eye development alters the expression patterns of some genes known to be important for eye morphogenesis, such as rx3/1 and six3a. Furthermore, exposure to ethanol interferes with the acquisition of neuroepithelial features by the eye field cells, which is clear at ultrastructual level. Indeed, ethanol disrupts the acquisition of fusiform cellular shapes within the eye field. In addition, tight junctions do not form and retinal progenitors do not properly polarize, as suggested by the mis-localization and down-regulation of zo1. We also show that the ethanol-induced cyclopic phenotype is significantly different to that observed in cyclopic mutants, suggesting a complex effect of ethanol on a variety of targets. Our results show that ethanol not only disrupts the expression pattern of genes involved in retinal morphogenesis, such as rx3 and rx1, but also disrupts the changes in cell polarity that normally occur during eye field splitting. Thus, ethylic teratology seems to be related not only to modifications in gene expression and cell death but also to alterations in cell morphology.

2013-01-01T00:00:00Z Sanchez-Simon, F.M. Santos Ledo, Adrián Arévalo Arévalo, María Rosario Rodríguez Rodriguez , Raquel Emilia http://hdl.handle.net/10366/161865 2026-02-19T12:57:50Z 2012-01-01T00:00:00Z

[EN]Opioids are the most potent analgesics known today, but their prolonged administration produces severe adverse effects such as constipation, bradycardia, besides addiction, a concept not fully understood at present, which represents one of the most important challenges of modern bioscience. Wnts constitute an important family of vertebrate genes that encode secreted signaling proteins implicated in various developmental processes (patterning of the neural tube, neuronal differentiation), and are extensively conserved through evolution. In this study we have focused on Wnt1, an essential signal in axis polarity, as well as in proliferation and the development and differentiation of the CNS, roles shared by opioid receptors. Our previous studies in zebrafish show that morphine, the most potent analgesic known today, increases cell proliferation and induces neuronal protection and dopaminergic differentiation by activating the opioid receptors. The aim of the present study is to determine whether these effects are a consequence of an interaction between Wnt1 and the endogenous opioid system, which may act as a transcription regulator of Wnt1. Hence, we have exposed embryos to morphine, the endogenous delta opioid agonist Met-Enkephalin-Glu-Tyr (MEGY) (it binds with high affinity to both zebrafish delta opioid receptors, ZfDORs), and SNC80, a highly specific delta agonist, which displays low affinity towards the ZfDORs. Although at earlier stages, all opioids reduced the expression level of Wnt1, further on development, mainly during the differentiation of the CNS (24–48 h post fertilization (hpf)), morphine and MEGY increased Wnt1 expression. Our results point to the possibility that opioid signaling controls the transcription of Wnt1 and that through Wnt1, the opioid system regulates cell proliferation and neuronal differentiation. The present work opens a door to the discovery of new mechanisms that regulate opioid activity and its adverse effects, and hence, it might provide a good target to design new drugs that prevent or avoid these effects.

2012-01-01T00:00:00Z Cid, Elena Santos Ledo, Adrián Parrilla-Monge, Marta Lillo Delgado, María Concepción Arévalo, Rosario Lara Pradas, Juan Manuel Aijón Noguera, José Velasco Arranz, María Almudena http://hdl.handle.net/10366/161856 2026-02-20T10:55:20Z 2010-02-01T00:00:00Z

[EN]The transcription factor Prox1 acts in rodent retinogenesis, at least in promoting cell cycle withdrawal and horizontal cell production. In the mature retina, this protein is detected at the inner nuclear layer of all vertebrate groups. We have made a neurochemical characterisation of Prox1(+) cell types in two different vertebrate groups: mammals and fish. As well as Prox1(+) horizontal cells, we have observed Prox1(+)/PKC-alpha(+) rod bipolar cells in mouse and cone ON and mixed b bipolar cells in goldfish. In mouse, only some CB(+) and CR(+) amacrine cells are Prox1(+) and the TH(+) and CR(+) amacrine cells are Prox1(-). However, in goldfish all CR(+) amacrine cells and TH(+) interplexiform cells are Prox1(+) and in the GCL displaced amacrine cells are also Prox1(+). Besides its expression in different interneuron subpopulations, we demonstrate, for the first time, the presence of Prox1 in the GS(+) and CRALBP(+) Müller cells in the retina of adult mammals and in developing and mature retina of fish. The presence of Prox1 in these cells appears to be related to survival or maintenance of their phenotype. We also demonstrate that in fish, where retinal formation persists into adulthood, Prox1 is expressed in dividing PCNA(+) cells at the peripheral growing zone, in rod progenitors at the inner and outer nuclear layers as well as in early progenitors during a retinal regeneration process after cryo-lesion of the peripheral growing zone. Therefore, Prox1 functions in vertebrate retinogenesis may be more complex than previously expected.

2010-02-01T00:00:00Z Saldaña Fernández, Enrique http://hdl.handle.net/10366/155485 2026-02-19T22:40:12Z 2015-07-04T00:00:00Z

[EN]Enrico Mugnaini has devoted part of his long and fruitful neuroscientific career to investigating the structural similarities between the cerebellar cortex and one of the first relay stations of the mammalian auditory pathway: the dorsal cochlear nucleus. The hypothesis of the cerebellar-like nature of the superficial layers of the dorsal cochlear nucleus received definitive support with the discovery and extensive characterization in his laboratory of unipolar brush cells, a neuron type unique to certain regions of the cerebellar cortex and to the granule cell domains of the cochlear nuclei. Paradoxically, a different line of research carried out in his laboratory revealed that, unlike the mammalian cerebellar cortex, the dorsal cochlear nucleus receives direct projections from the cerebral cortex, a fact that constitutes one of the main differences between the cerebellum and the dorsal cochlear nucleus. In an article published in 1995, Mugnaini's group described in detail the novel direct projections from the rat auditory neocortex to various subcollicular auditory centers, including the nucleus sagulum, the paralemniscal regions, the superior olivary complex, and the cochlear nuclei (Feliciano et al., Auditory Neuroscience 1995; 1:287-308). This review gives Enrico Mugnaini credit for his seminal contribution to the knowledge of auditory corticosubcollicular projections and summarizes how this growing field has evolved in the last 20 years.

2015-07-04T00:00:00Z Felix II, Richard A. Gourévitch, Boris Gómez Álvarez, Marcelo Leijon, Sara C. M. Saldaña Fernández, Enrique Magnusson, Anna K. http://hdl.handle.net/10366/155480 2026-02-19T22:46:54Z 2017-05-31T00:00:00Z

[EN]Auditory streaming enables perception and interpretation of complex acoustic environments that contain competing sound sources. At early stages of central processing, sounds are segregated into separate streams representing attributes that later merge into acoustic objects. Streaming of temporal cues is critical for perceiving vocal communication, such as human speech, but our understanding of circuits that underlie this process is lacking, particularly at subcortical levels. The superior paraolivary nucleus (SPON), a prominent group of inhibitory neurons in the mammalian brainstem, has been implicated in processing temporal information needed for the segmentation of ongoing complex sounds into discrete events. The SPON requires temporally precise and robust excitatory input(s) to convey information about the steep rise in sound amplitude that marks the onset of voiced sound elements. Unfortunately, the sources of excitation to the SPON and the impact of these inputs on the behavior of SPON neurons have yet to be resolved. Using anatomical tract tracing and immunohistochemistry, we identified octopus cells in the contralateral cochlear nucleus (CN) as the primary source of excitatory input to the SPON. Cluster analysis of miniature excitatory events also indicated that the majority of SPON neurons receive one type of excitatory input. Precise octopus cell-driven onset spiking coupled with transient offset spiking make SPON responses well-suited to signal transitions in sound energy contained in vocalizations. Targets of octopus cell projections, including the SPON, are strongly implicated in the processing of temporal sound features, which suggests a common pathway that conveys information critical for perception of complex natural sounds.

2017-05-31T00:00:00Z