Persistent inflammatory state after photoreceptor loss in an animal model of retinal degeneration

Microglia act as the resident immune cells of the central nervous system, including the retina. In response to damaging stimuli microglia adopt an activated state, which can progress into a phagocytic phenotype and play a potentially harmful role by eliciting the expression and release of pro-inflammatory cytokines. The aim of the present study was to assess longitudinal changes in microglia during retinal degeneration in the homozygous P23H rat, a model of dominant retinitis pigmentosa. Microglial phenotypes, morphology and density were analyzed by immunohistochemistry, flow cytometry, and cytokine antibody array. In addition, we performed electroretinograms to evaluate the retinal response. In the P23H retina, sclera, choroid and ciliary body, inflammatory cells increased in number compared with the control at all ages analyzed. As the rats became older, a higher number of amoeboid MHC-II+ cells were observed in the P23H retina, which correlated with an increase in the expression of pro-inflammatory cytokines. These findings suggest that, in the P23H model, retinal neuroinflammation persists throughout the rat’s life span even after photoreceptor depletion. Therefore, the inclusion of anti-inflammatory drugs at advanced stages of the neurodegenerative process may provide better retinal fitness so the remaining cells could still be used as targets of cellular or gene therapies.This work was supported by grants from the Spanish Ministry of the Economy and Competitiveness-FEDER (BFU2012-36845, BFU2015-67139-R), Instituto de Salud Carlos III (RETICS-FEDER RD12/0034/0010), Organización Nacional de Ciegos Españoles (ONCE), Asociación Retina Asturias, FUNDALUCE and Fundación Jesús de Gangoiti Barrera

Natural Compounds from Saffron and Bear Bile Prevent Vision Loss and Retinal Degeneration

All retinal disorders, regardless of their aetiology, involve the activation of oxidative stress and apoptosis pathways. The administration of neuroprotective factors is crucial in all phases of the pathology, even when vision has been completely lost. The retina is one of the most susceptible tissues to reactive oxygen species damage. On the other hand, proper development and functioning of the retina requires a precise balance between the processes of proliferation, differentiation and programmed cell death. The life-or-death decision seems to be the result of a complex balance between pro- and anti-apoptotic signals. It has been recently shown the efficacy of natural products to slow retinal degenerative process through different pathways. In this review, we assess the neuroprotective effect of two compounds used in the ancient pharmacopoeia. On one hand, it has been demonstrated that administration of the saffron constituent safranal to P23H rats, an animal model of retinitis pigmentosa, preserves photoreceptor morphology and number, the capillary network and the visual response. On the other hand, it has been shown that systemic administration of tauroursodeoxycholic acid (TUDCA), the major component of bear bile, to P23H rats preserves cone and rod structure and function, together with their contact with postsynaptic neurons. The neuroprotective effects of safranal and TUDCA make these compounds potentially useful for therapeutic applications in retinal degenerative diseases.This research was supported by grants from the Spanish Ministry of Economy and Competitiveness-FEDER (BFU2012-36845), Instituto de Salud Carlos III (RETICS RD12/0034/0010), Asociación Retina Asturias, Fundación Jesús Gangoiti, Organización Nacional de Ciegos Españoles (ONCE) and FUNDALUCE

Systemic inflammation induced by lipopolysaccharide aggravates inherited retinal dystrophy

Retinal neurodegenerative diseases involve a scenario of inflammation and cell death that leads to morphological alterations and visual impairment. Non-ocular inflammatory processes could affect neurodegenerative retinal disorders and their progression, at least in part by activating microglial cells and releasing pro-inflammatory cytokines. Our purpose was to study the consequences of a systemic inflammatory process in the progression of retinal degeneration in P23H rats, a retinitis pigmentosa (RP) model. In order to induce a mild chronic systemic inflammation, we administered low doses of lipopolysaccharide (LPS) from age P20 to P60 to dystrophic P23H rats and healthy SD rats. Visual responsiveness was assessed by electroretinography (ERG). The morphological state of the retinas was analyzed by fluorescent immunohistochemistry (IHC), evaluating the number, morphology, and connectivity of different neuronal populations by means of cell type-specific markers. Microglia density, distribution, and degree of activation were evaluated by IHC and flow cytometry. The expression levels of inflammation- and apoptosis-related genes were analyzed by qRT-PCR arrays. Low-dose LPS administration did not induce significant functional or morphological changes in the retina of SD rats, although at the molecular level, we detected expression changes in genes related to apoptosis. Otherwise, systemic injection of LPS into P23H rats induced a further deterioration in the ERG response, with greater loss of photoreceptors and worsening of synaptic connectivity, accompanied by increasing numbers of microglial cells, which also showed a more intense activation state. Several inflammation- and apoptosis-related genes were upregulated. Our results indicate that chronic exacerbation of the inflammatory response in response to LPS accelerates neurodegeneration in dystrophic P23H rats, suggesting that in patients with ocular neurodegenerative diseases, peripheral damage, as a systemic infection or chronic inflammatory process, could accelerate disease progression, and should be taken into account in order to select an appropriate therapy to revert, block or slow-down the degenerative process.This research was supported by grants from the Spanish Ministry of Economy and Competitiveness (MINECO-FEDER BFU2015-67139-R), Instituto de Salud Carlos III (RETICS-FEDER RD16/0008/0016), Asociación Retina Asturias, and the Regional Government of Valencia (PROMETEO/2016/158)

Sodium Hyaluronate-Induced Ocular Hypertension in Rats Damages the Direction-Selective Circuit and Inner/Outer Retinal Plexiform Layers

Purpose: To assess the changes in retinal morphology in a rat model of chronic glaucoma induced by ocular hypertension. Methods: Intraocular pressure (IOP) was surgically increased through weekly injections of sodium hyaluronate (HYA) in the anterior eye chamber of the left eye of male Wistar rats, whereas the right eyes were sham operated (salt solution). During the 10-week experimental period, IOP was measured weekly with a rebound tonometer. Retinal cryosections were prepared for histological/immunohistochemical analysis and morphometry. Results: IOP was higher in HYA-treated eyes than in sham-operated eyes along the 10-week period, which was significant from the fourth to the nineth week. Ocular hypertension in HYA-treated eyes was associated with morphologic and morphometric changes in bipolar cells, ON-OFF direction-selective ganglion cells, ON/OFF starburst amacrine cells, and inner plexiform layer sublamina. Conclusions: Serial HYA treatment in the rat anterior eye chamber results in mild-to-moderate elevated and sustained IOP and ganglion cell death, which mimics most human open-angle glaucoma hallmarks. The reduced number of direction-selective ganglion cells and starburst amacrine cells accompanied by a deteriorated ON/OFF plexus in this glaucoma model could lend insight to the abnormalities in motion perception observed in patients with glaucoma.Supported by the Spanish Ministry of Science and Innovation (MICINN-FEDER PID2019-106230RB-I00), 2), Institute of Health Carlos III (General Subdirection of Networks and Cooperative Research Centers RETICs OFTARED 2012-2021) co-financed by the European Regional Development fund (RD16/0008/0016 [Alicante] and RD16/0008/0022 [Valencia]), Asociación Retina Asturias (ASOCIACIONRETINA1-20I), Generalitat Valenciana (IDIFEDER/2017/064), and the Research funds from both Department of Surgery (Ophthalmology Unit) and Cellular-Molecular Ophthalmobiology Group of the University of Valencia (Spain)

Ensayo de evaluación a distancia frente a evaluación presencial

El sistema de evaluación debe valorar las competencias adquiridas por el estudiante según los conocimientos, habilidades y aptitudes que ha desarrollado a lo largo del proceso de enseñanza-aprendizaje. Este proceso debe ser válido, además de confiable y práctico. Es necesario estudiar los diversos métodos de evaluación disponibles y su idoneidad para las distintas actividades de los grados. El hecho de disponer de herramientas que permiten realizar una evaluación a distancia nos hizo plantearnos la idoneidad de este sistema. Así pues, con el objeto de evaluar la fiabilidad de la evaluación a distancia, se realizó una experiencia en la que se compararon las calificaciones obtenidas en actividades prácticas y seminarios, empleando ambas modalidades de evaluación: presencial y a distancia, mediante las herramientas del campus virtual. Como pudimos comprobar, no hubo diferencias significativas según la modalidad de evaluación, por lo que, con los datos de los que disponemos, podemos aceptar ambos sistemas como igualmente efectivos. Estudiamos también el efecto de la realización de una prueba previa de autoevaluación. En este caso sí encontramos como consecuencia un ligero incremento en la nota, por lo que recomendamos esta actividad para la mejora del rendimiento académico

Immunosuppression, peripheral inflammation and invasive infection from endogenous gut microbiota activate retinal microglia in mouse models

Although its actual role in the progression of degenerative processes is not fully known, the persistent activated state of retinal microglia and the concurrent secretion of inflammatory mediators may contribute to neuronal death and permanent vision loss. Our objective was to determine whether non-ocular conditions (immunosuppression and peripheral inflammation) could lead to activation of retinal microglia. Mouse models of immunosuppression induced by cyclophosphamide and/or peripheral inflammation by chemically induced sublethal colitis in C57BL/6J mice were used. Retinal microglia morphology, spatial distribution and complexity, as well as MHCII and CD11b expression levels were determined by flow cytometry and confocal immunofluorescence analysis with anti-CD11b, anti-IBA1 and anti-MHCIIRT1B antibodies. Retinas of mice with double treatment showed changes in microglial morphology, spatial distribution and expression levels of CD11b and MHCII. These effects were higher than those observed with any treatment separately. In addition, we also observed in these mice: (i) translocation of endogenous bacteria from gut to liver, and (ii) upregulation of TLR2 expression in retinal microglia. Using a mouse model of immunosuppression and gut colonization by Candida albicans, translocation of fungal cells was confirmed to occur in wild type and, to a higher extent, in TLR2 KO mice, which are more susceptible to fungal invasion; interestingly microglial changes were also higher in TLR2 KO mice. Hence, non-ocular injuries (immunosuppression, peripheral inflammation and invasive infection from endogenous gut microbiota) can activate retinal microglia and therefore could affect the progression of neurodegenerative disorders and should be taken into account to improve therapeutic options.This study was supported by project grants from the Spanish Ministry of Economy and Competitiveness-FEDER BFU2012-36845, Instituto de Salud Carlos III RETICS RD12/0034/0010, FUNDALUCE, Retina Asturias, ONCE and Fundación Jesús de Gangoiti Barrera

Purinergic Receptors P2X7 and P2X4 as Markers of Disease Progression in the rd10 Mouse Model of Inherited Retinal Dystrophy

The purinergic receptor P2X7 (P2X7R) is implicated in all neurodegenerative diseases of the central nervous system. It is also involved in the retinal degeneration associated with glaucoma, age-related macular degeneration, and diabetic retinopathy, and its overexpression in the retina is evident in these disorders. Retinitis pigmentosa is a progressive degenerative disease that ultimately leads to blindness. Here, we investigated the expression of P2X7R during disease progression in the rd10 mouse model of RP. As the purinergic receptor P2X4 is widely co-expressed with P2X7R, we also studied its expression in the retina of rd10 mice. The expression of P2X7R and P2X4R was examined by immunohistochemistry, flow cytometry, and western blotting. In addition, we analyzed retinal functionality by electroretinographic recordings of visual responses and optomotor tests and retinal morphology. We found that the expression of P2X7R and P2X4R increased in rd10 mice concomitant with disease progression, but with different cellular localization. Our findings suggest that P2X7R and P2X4R might play an important role in RP progression, which should be further analyzed for the pharmacological treatment of inherited retinal dystrophies.This research was funded by grants from the Spanish Ministry of the Economy and Competitiveness (RTI2018-094248-B-I00), Spanish Ministry of Science and Innovation co-financed by European Regional Development Fund (MICINN-FEDER PID2019-106230RB-I00), Instituto de Salud Carlos III co-financed by European Regional Development Fund (RETICS-FEDER-RD16/0008/0016), Asociación Retina Asturias (ASOCIACIONRETINA1-20I), and Generalitat Valenciana (PROMETEO/2021/024, IDIFEDER/2017/064), and by a grant (MARSALAS21-35) to L.V

Rendimiento académico del ABP en Anatomía

Desde que en la Universidad de Alicante se implantaron los nuevos planes de estudios EEES en el curso 2010-11, hasta la actualidad, se ha estado aplicando la metodología docente colaborativa de aprendizaje basado en problemas (ABP) en asignaturas del área de Anatomía Humana y Embriología impartidas en los primeros cursos de las titulaciones de Grado en “Enfermería”, “Nutrición Humana y Dietética”, “Óptica y Optometría” y “Ciencias de la Actividad Física y del Deporte”. El objetivo de este estudio es comparar los resultados de aprendizaje a través del rendimiento académico obtenido en la evaluación continua según diferentes metodologías docentes. En general, las calificaciones obtenidas en la evaluación de la exposición oral en grupo del trabajo ABP fueron mucho mejores en todas las asignaturas a lo largo de los últimos 5 años. Los resultados de las pruebas objetivas de respuesta múltiple usadas para evaluar los logros de aprendizaje mediante el uso de clases magistrales de teoría y prácticas de laboratorio fueron algo inferiores. Se plantea la posibilidad de incrementar el número de actividades de ABP y asignar un mayor peso en la ponderación de los criterios de evaluación de la asignatura

Integración del inglés en materias de Anatomía

En el curso 2012-13 iniciamos un proyecto de trabajo en red para favorecer la integración del inglés en 5 materias de Ciencias de la Salud. Dado que el aprendizaje de esta segunda lengua es una competencia básica transversal e instrumental en los Grados de la Universidad de Alicante, en el presente estudio pretendemos valorar el nivel de adquisición simultánea en lengua inglesa y española de nuevos términos anatómicos, así como el nivel de conocimientos genéricos de comprensión lectora y escritora del inglés. Para ello, al principio y final del primer semestre del curso 2013-14, se realizaron encuestas con preguntas de respuesta múltiple en las asignaturas de Anatomía impartidas en los primeros cursos de 4 Grados: Enfermería, Nutrición Humana y Dietética, Óptica y Optometría y Ciencias de la Actividad Física y del Deporte. Observamos una cierta mejora en la adquisición de términos anatómicos en inglés según el sistema de aprendizaje integrado de contenidos en lengua extranjera (AICLE). Sin embargo, los conceptos genéricos de la lengua inglesa permanecen constantes o incluso se algo disminuidos. Concluimos que en un entorno AICLE, con materiales curriculares bilingües, se obtienen buenos resultados de aprendizaje en las materias de Anatomía integradas con el inglés

¿Se aprende inglés a la vez que anatomía?

Continuando un proyecto previo, se pretende favorecer la integración del inglés en materias de Ciencias de la Salud impartidas en los Grados de Enfermería, Nutrición Humana y Dietética, Óptica y Optometría y Ciencias de la Actividad Física y del Deporte de la Universidad de Alicante. En el curso 2013-14 se obtienen y analizan los resultados de las encuestas sobre el progreso del aprendizaje y competencias en inglés según el sistema de aprendizaje integrado de contenidos en lengua extranjera (AICLE). Mediante una encuesta de preguntas de respuesta múltiple se valoran las competencias lectoras y escritoras en inglés genérico y específico para contenidos de Anatomía impartidos en cada una de las asignaturas. Con una pregunta de valoración subjetiva se obtiene una aproximación del nivel de conocimientos de inglés que cada alumno considera poseer. Estas encuestas se respondieron al principio y final del primer cuatrimestre. En general, se aprecia una cierta mejora en los aprendizajes de términos anatómicos en inglés, mientras que los relativos a conceptos genéricos de la lengua inglesa permanecen constantes o incluso ligeramente mermados. Se concluye que en un entorno AICLE, con materiales curriculares bilingües, se obtienen buenos resultados de aprendizaje propios de cada materia integrada con el inglés