Evaluación in vitro del potencial neuroprotector de las células madre mesenquimales sobre los fotorreceptores

La degeneración de los fotorreceptores (FR) es un proceso en el cuál confluyen diversas enfermedades neurodegenerativas de la retina como son la degeneración macular asociada a edad o la retinitis pigmentosa. Enfermedades que representan unas de las principales causas de ceguera a nivel mundial ya que actualmente carecen de un tratamiento realmente efectivo. Las terapias avanzadas se muestran como una alternativa para el tratamiento de este tipo de patologías; entre ellas, la terapia celular mediada por factores paracrinos se perfila como la alternativa más viable. En este sentido, la utilización de células madre mesenquimales (MSCs) podría frenar la degeneración que sufren los FR retinianos en este tipo de patologías. Por ello éste trabajo se planteó el estudio inmunohistoquímico de los FR tras el cocultivo de la retina con las MSCs y el análisis del secretoma proteico tras el cocultivo. Los resultados del presente trabajo mostraron como las MSCs tenían la capacidad de frenar la neurodegeneración de la capa de FR de la retina. Lo que sugiere su posible futura aplicación en tratamientos de terapia celular destinados a pacientes que sufren distrofias retinianas que cursan con la degeneración de los FR. También se muestra como el efecto neuroprotector desarrollado por las MSCs se podría basar en la secreción de factores proteicos por parte de las MSCs, que estarían destinados a contrarrestar los procesos típicos de la degeneración retiniana. Todo ello sienta las bases para, en un futuro, elaborar terapias neuroprotectoras basadas en la combinación de factores neuroprotectores procedentes de las MSCs.Departamento de Cirugía, Oftalmología, Otorrinolaringología y FisioterapiaMáster en Investigación en Ciencias de la Visió

Safety, biocompatibility, and potential functionality of a new accommodative intraocular lens: An experimental study in rabbits

Producción CientíficaThis study aims to evaluate the safety, biocompatibility, and functionality of a new accommodative intraocular lens (IOL) (LUZ, patent PCT/ES2016/070,813) after implantation in rabbit eyes. LUZ (Study) and EyeCee® plus a capsular ring (Control) were implanted in rabbits (n = 8 each) after phacoemulsification. Intraoperative follow-up, long-term clinical follow-up, and functional IOL studies were carried out periodically for up to 180 days. A macroscopic examination of the eyeballs to reveal abnormalities and determine the implant centering and a microscopic examination to semi-quantify cell and tissue response were performed. Statistical analysis of the collected data was finally achieved. During follow-up, no significant changes in the general condition nor the clinical evaluation were observed between both groups. However, Study IOL remained centered throughout the study and did not present severe complications as observed in the Control group. Functional studies did not reveal significant differences between both materials. Study showed better centering, fewer adhesions, and maintenance of an opening capsular bag compared to the Control. Local biological effects caused by Study implantation are minimal and comparable to the Control. Therefore, LUZ showed no clinical signs or histological response of adverse reaction to the implanted material, according to UNE-EN ISO 11979-5 and 10993-6. Functionality must be confirmed in another animal species with greater lens accommodation capacity than the rabbit. LUZ keeps the capsular bag open, favoring its centering and avoiding fibrosis and adherence to the bag; this allows potential accommodation of this IOL and theoretically enables the patient to focus dynamically.Ministerio de Ciencia e Innovación (Neotec Project EXP-00104711/SNEO-20171172

Hair cortisol level as a molecular biomarker in retinitis pigmentosa patients

Producción CientíficaPurpose: Retinitis pigmentosa (RP) patients commonly experience negative psychological states due to their progressive and unpredictable loss of vision and visual variations related to stress. The aim of this study was to examine hair cortisol concentrations (HCCs), which is usually associated with chronic stress, pretending to unveil possible associations between underlying psychological factors and disease severity in RP patients. Methods: Seventy-eight RP patients and 148 healthy controls were included in this study. A complete ophthalmological exam was performed in all patients to grade into severity disease groups. Perceived stress and trait-anxiety were measured by the State-Trait Anxiety Inventory (STAI) questionnaire. Results: Fifty-two (67%) patients had severe RP and 26 (33%) mild-moderate RP. Fifty-eight (58,9%) patients reported severely levels of stress and 18 (23.,1%) highly levels assessed by STAI questionnaire. RP patients exhibited higher HCCs (500.04 ± 120.99 pg/mg) than in controls (136.17 ± 60.51 pg/mg; p < 0.001). Severe RP patients had significant higher HCCs than mild-moderate patients differing in 274.27 pg/mg (p < 0.001). RP severity grade and perceived anxiety levels in the questionaries were not associated. Group differences were not affected by relevant covariates (age, grade of severity, stress status, and gender). Conclusions: HCC seems an effective biomarker associated with chronic stress in RP patients. This study shows that HCC in patients with RP are elevated compared to population-based controls, and association between HCC and RP severity was found. Future research is needed to characterize the effect of untreated negative psychological states on progression of the disease if any.Gerencia Regional de Salud de Castilla y León (GRS, 1932/A/19)Ministerio de Ciencia, Innovación y Universidades (grant PID2020-114585RA-I00

Retinal neuroprotective effect of mesenchymal stem cells secretome through modulation of oxidative stress, autophagy, and programmed cell death

Producción CientíficaPurpose: Degenerative mechanisms of retinal neurodegenerative diseases (RND) share common cellular and molecular signalization pathways. Curative treatment does not exist and cell-based therapy, through the paracrine properties of mesenchymal stem cells (MSC), is a potential unspecific treatment for RND. This study aimed to evaluate the neuroprotective capability of human bone marrow (bm) MSC secretome and its potential to modulate retinal responses to neurodegeneration. Methods: An in vitro model of spontaneous retinal neurodegeneration was used to compare three days of monocultured neuroretina (NR), NR cocultured with bmMSC, and NR cultured with bmMSC secretome. We evaluated retinal morphology markers (Lectin peanut agglutinin, rhodopsin, protein kinase C α isoform, neuronal-specific nuclear protein, glial fibrillary acidic protein, TdT-mediated dUTP nick-end labeling, and vimentin) and proteins involved in apoptosis (apoptosis-inductor factor, caspase-3), necroptosis (MLKL), and autophagy (p62). Besides, we analyzed the relative mRNA expression through qPCR of genes involved in apoptosis (BAX, BCL2, CASP3, CASP8, CASP9), necroptosis (MLKL, RIPK1, RIPK3), autophagy (ATG7, BCLIN1, LC3B, mTOR, SQSTM1), oxidative stress (COX2, CYBA, CYBB, GPX6, SOD1, TXN2, TXNRD1) and inflammation (IL1, IL6, IL10, TGFb1, TNFa). Results: The bmMSC secretome preserves retinal morphology, limits pro-apoptotic– and pro-necroptotic–related gene and protein expression, modulates autophagy-related genes and proteins, and stimulates the activation of antioxidant-associated genes. Conclusions: The neuroprotective ability of the bmMSC secretome is associated with activation of antioxidant machinery, modulation of autophagy, and inhibition of apoptosis and necroptosis during retinal degeneration. The neuroprotective effect of bmMSC secretomes in the presence/absence of MSC looks similar. Our current results reinforce the hypothesis that the human bmMSC secretome slows retinal neurodegeneration and may be a therapeutic option for treating RND.Gobierno de España (PID2019-110709RB-100, RED2018-102417-T, FPU16/04015, PID2020-114585RA-I00 and PID2020-118860RB-I00)Junta de Castilla y León (VA317P18, Infrared2018-UVA06, and GRS1928/A/19)Interred V España-Portugal POCTEP (0624_2IQBIONEURO_6_E