Management of wet age-related macular degeneration in Spain: challenges for treat and extend implementation in routine clinical practice

Age-related macular degeneration; Ophthalmology services; Anti-VEGFDegeneración macular relacionada con la edad; Servicios de oftalmología; Anti-VEGFDegeneració macular relacionada amb l’edat; Serveis d’oftalmologia; Anti-VEGFPurpose. To ascertain wet AMD (wAMD) management patterns in Spain. Methods. A two-round Delphi study conducted through a questionnaire-based survey designed from literature review and validated by an independent Steering Committee. Results. Forty-nine retina specialists experienced in wAMD participated by answering the two-round study questionnaire. Retina specialists are the main responsible for wAMD diagnosis and monitoring, including visits and associated procedures, with a median time per visit of 15 minutes. Standard treatment strategies are based on anti-VEGF administration, including standard loading dose administration followed by maintenance with aflibercept or ranibizumab (81% of patients). Although treat and extend (T&E) dosing strategy is considered as optimal for wAMD management (78% of the panelists), the main routine healthcare limitations (i.e., visits overload, reduced staff, short visit time, coordination issues, lack of facilities) conduct to self-defined “flexible” strategies, based on T&E and pro-re-nata (PRN) protocols. Conclusion. Proactive treatment patterns (T&E) are the preferred ones by the retina specialists in Spain. However, their proper implementation is difficult due to healthcare resource limitations, as well as organisation and logistic issues. The use of anti-VEGF agents with longer duration of action could facilitate the use of strict T&E approaches according to routine clinical practices

Management of wet age-related macular degeneration in Spain: Challenges for treat and extend implementation in routine clinical practice

Purpose. To ascertain wet AMD (wAMD) management patterns in Spain. Methods. A two-round Delphi study conducted through a questionnaire-based survey designed from literature review and validated by an independent Steering Committee. Results. Forty-nine retina specialists experienced in wAMD participated by answering the two-round study questionnaire. Retina specialists are the main responsible for wAMD diagnosis and monitoring, including visits and associated procedures, with a median time per visit of 15 minutes. Standard treatment strategies are based on anti-VEGF administration, including standard loading dose administration followed by maintenance with aflibercept or ranibizumab (81% of patients). Although treat and extend (T&E) dosing strategy is considered as optimal for wAMD management (78% of the panelists), the main routine healthcare limitations (i.e., visits overload, reduced staff, short visit time, coordination issues, lack of facilities) conduct to self-defined “flexible” strategies, based on T&E and pro-re-nata (PRN) protocols. Conclusion. Proactive treatment patterns (T&E) are the preferred ones by the retina specialists in Spain. However, their proper implementation is difficult due to healthcare resource limitations, as well as organisation and logistic issues. .e use of anti-VEGF agents with longer duration of action could facilitate the use of strict T&E approaches according to routine clinical practicesThe study has been sponsored by Bayer Hispania S.L. Logistic

MicroRNA-mediated differential expression of TRMU, GTPBP3 and MTO1 in cell models of mitochondrial-DNA diseases

Mitochondrial diseases due to mutations in the mitochondrial (mt) DNA are heterogeneous in clinical manifestations but usually include OXPHOS dysfunction. Mechanisms by which OXPHOS dysfunction contributes to the disease phenotype invoke, apart from cell energy deficit, maladaptive responses to mitochondria-to-nucleus retrograde signaling. Here we used five different cybrid models of mtDNA diseases to demonstrate that the expression of the nuclear-encoded mt-tRNA modification enzymes TRMU, GTPBP3 and MTO1 varies in response to specific pathological mtDNA mutations, thus altering the modification status of mt-tRNAs. Importantly, we demonstrated that the expression of TRMU, GTPBP3 and MTO1 is regulated by different miRNAs, which are induced by retrograde signals like ROS and Ca2+ via different pathways. Our data suggest that the up- or down-regulation of the mt-tRNA modification enzymes is part of a cellular response to cope with a stoichiometric imbalance between mtDNA- and nuclear-encoded OXPHOS subunits. However, this miRNA-mediated response fails to provide full protection from the OXPHOS dysfunction; rather, it appears to aggravate the phenotype since transfection of the mutant cybrids with miRNA antagonists improves the energetic state of the cells, which opens up options for new therapeutic approaches

Identification and Characterization of New RNASEH1 Mutations Associated With PEO Syndrome and Multiple Mitochondrial DNA Deletions

RNASEH1; Mitochondrial disease; MtDNARNASEH1; Malaltia mitocondrial; ADN mitocondrialRNASEH1; Enfermedad mitocondrial; ADN mitocondrialMitochondrial DNA (mtDNA) depletion and deletion syndrome encompasses a group of disorders caused by mutations in genes involved in mtDNA replication and maintenance. The clinical phenotype ranges from fatal infantile hepatocerebral forms to mild adult onset progressive external ophthalmoplegia (PEO). We report the case of a patient with PEO and multiple mtDNA deletions, with two new homozygous mutations in RNASEH1. The first mutation (c.487T>C) is located in the same catalytic domain as the four previously reported mutations, and the second (c.258_260del) is located in the connection domain, where no mutations have been reported. In silico study of the mutations predicted only the first mutation as pathogenic, but functional studies showed that both mutations cause loss of ribonuclease H1 activity. mtDNA replication dysfunction was demonstrated in patient fibroblasts, which were unable to recover normal mtDNA copy number after ethidium bromide-induced mtDNA depletion. Our results demonstrate the pathogenicity of two new RNASEH1 variants found in a patient with PEO syndrome, multiple deletions, and mild mitochondrial myopathy.This work was supported by the Spanish Instituto de Salud Carlos III, Fondo de Investigaciones Sanitarias and cofunded with ERDF funds (Grant No. FIS PI15/01428 to EG-A and FIS PI18/01574 to RM), the Spanish Ministry of Industry, Economy and Competitiveness (Grant No. SAF2017-87506-R to YC), and the Generalitat de Catalunya (a grant from the URDCat project PERIS to EG-A and RM). JT-T was funded by a fellowship granted by the Generalitat de Catalunya (PERIS program, SLT002/16/00370

Multicentric standardization of protocols for the diagnosis of human mitochondrial respiratory chain defects

The quantification of mitochondrial respiratory chain (MRC) enzymatic activities is essential for diagnosis of a wide range of mitochondrial diseases, ranging from inherited defects to secondary dysfunctions. MRC lesion is frequently linked to extended cell damage through the generation of proton leak or oxidative stress, threatening organ viability and patient health. However, the intrinsic challenge of a methodological setup and the high variability in measuring MRC enzymatic activities represents a major obstacle for comparative analysis amongst institutions. To improve experimental and statistical robustness, seven Spanish centers with extensive experience in mitochondrial research and diagnosis joined to standardize common protocols for spectrophotometric MRC enzymatic measurements using minimum amounts of sample. Herein, we present the detailed protocols, reference ranges, tips and troubleshooting methods for experimental and analytical setups in different sample preparations and tissues that will allow an international standardization of common protocols for the diagnosis of MRC defects. Methodological standardization is a crucial step to obtain comparable reference ranges and international standards for laboratory assays to set the path for further diagnosis and research in the field of mitochondrial diseases. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Multicentric Standardization of Protocols for the Diagnosis of Human Mitochondrial Respiratory Chain Defects

The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Institutional Review Board of each institution: IBC U737 (C0000128), HCL U722 (HCB2017/0808), 12O U723 (CEI:18/487), VH U701 (PR(IR)63/2016) and UPO U729 (C.I. 2768-N-21)The quantification of mitochondrial respiratory chain (MRC) enzymatic activities is essential for diagnosis of a wide range of mitochondrial diseases, ranging from inherited defects to secondary dysfunctions. MRC lesion is frequently linked to extended cell damage through the generation of proton leak or oxidative stress, threatening organ viability and patient health. However, the intrinsic challenge of a methodological setup and the high variability in measuring MRC enzymatic activities represents a major obstacle for comparative analysis amongst institutions. To improve experimental and statistical robustness, seven Spanish centers with extensive experience in mitochondrial research and diagnosis joined to standardize common protocols for spectrophotometric MRC enzymatic measurements using minimum amounts of sample. Herein, we present the detailed protocols, reference ranges, tips and troubleshooting methods for experimental and analytical setups in different sample preparations and tissues that will allow an international standardization of common protocols for the diagnosis of MRC defects. Methodological standardization is a crucial step to obtain comparable reference ranges and international standards for laboratory assays to set the path for further diagnosis and research in the field of mitochondrial diseasesThis work was supported by Instituto de Salud Carlos III (ISCIII), grants FIS PI17/00021, PI17/00359, PI18/00498, PI18/00451, PI18/01374, PI19/01772, PI20/00541, PI21/00229, PI21/00381 and PI21/00935 (ISCIII-FEDER “Cofinanciado por la Unión Europea”), Fundació Privada Cellex, Junta de Andalucía (UPO-1262247) and Ministerio de Ciencia e Innovación (MCINN) grant PID2019-110320RBI00. All participant centers are integrated in the Centro de Investigación Biomédica en Red (CIBER), Sección de Enfermedades Raras (CIBERER, an initiative of ISCIII), which is the founder of this present methodological stud

Functional and structural findings of neurodegeneration in early stages of diabetic retinopathy:cross-sectional analyses of baseline data of the EUROCONDOR project

Cross-sectional study evaluating the relationship between: a) functional and structural measurements of neurodegeneration in initial stages of diabetic retinopathy (DR); and b) presence of neurodegeneration and early microvascular impairment. We analyzed baseline data of patients with type 2 diabetes (n=449) enrolled in the EUROCONDOR study (NCT01726075). Functional studies by multifocal ERG (mfERG) evaluated neurodysfunction and structural measurements using spectral domain optical-coherence tomography (SD-OCT) evaluated neurodegeneration. The mfERG P1 amplitude was more sensitive than the P1 implicit time (IT), and was lower in patients with ETDRS 20-35 than in patients with ETDRS <20 (p=0.005). In 58% of cases, mfERG abnormalities were present in the absence of visible retinopathy. Correspondence between SD-OCT thinning and mfERG abnormalities was shown in 67% of the eyes with ETDRS <20 and in 83% of the eyes with ETDRS 20-35. Notably, 32% of patients with ETDRS 20-35 presented no abnormalities in mfERG or SD-OCT. We conclude that there is a link between mfERG and SD-OCT measurements which increases with the presence of microvascular impairment. However, in our particular study population (ETDRS ≤ 35) a significant proportion of patients had normal GC-IPL thickness and normal mfERG findings. We raise the hypothesis that neurodegeneration may play a role in the pathogenesis of DR in many, but not in all type 2 diabetic patients

CIBERER : Spanish national network for research on rare diseases: A highly productive collaborative initiative

Altres ajuts: Instituto de Salud Carlos III (ISCIII); Ministerio de Ciencia e Innovación.CIBER (Center for Biomedical Network Research; Centro de Investigación Biomédica En Red) is a public national consortium created in 2006 under the umbrella of the Spanish National Institute of Health Carlos III (ISCIII). This innovative research structure comprises 11 different specific areas dedicated to the main public health priorities in the National Health System. CIBERER, the thematic area of CIBER focused on rare diseases (RDs) currently consists of 75 research groups belonging to universities, research centers, and hospitals of the entire country. CIBERER's mission is to be a center prioritizing and favoring collaboration and cooperation between biomedical and clinical research groups, with special emphasis on the aspects of genetic, molecular, biochemical, and cellular research of RDs. This research is the basis for providing new tools for the diagnosis and therapy of low-prevalence diseases, in line with the International Rare Diseases Research Consortium (IRDiRC) objectives, thus favoring translational research between the scientific environment of the laboratory and the clinical setting of health centers. In this article, we intend to review CIBERER's 15-year journey and summarize the main results obtained in terms of internationalization, scientific production, contributions toward the discovery of new therapies and novel genes associated to diseases, cooperation with patients' associations and many other topics related to RD research