Role of Lnc-RNAs in the Pathogenesis and Development of Diabetic Retinopathy.

Important advances in diabetic retinopathy (DR) research and management have occurred in the last few years. Neurodegenerative changes before the onset of microvascular alterations have been well established. So, new strategies are required for earlier and more effective treatment of DR, which still is the first cause of blindness in working age. We describe herein gene regulation through Lnc-RNAs as an interesting subject related to DR. Long non-coding RNAs (Lnc-RNAs) are non-protein-coding transcripts larger than 200 nucleotides. Lnc-RNAs regulate gene expression and protein formation at the epigenetic, transcriptional, and translational levels and can impact cell proliferation, apoptosis, immune response, and oxidative stress. These changes are known to take part in the mechanism of DR. Recent investigations pointed out that Lnc-RNAs might play a role in retinopathy development as Metastasis-Associated Lung Adenocarcinoma Transcript (Lnc-MALAT1), Maternally expressed gene 3 (Lnc-MEG3), myocardial-infarction-associated transcript (Lnc-MIAT), Lnc-RNA H19, Lnc-RNA HOTAIR, Lnc-RNA ANRIL B-Raf proto-oncogene (Lnc-RNA BANCR), small nucleolar RNA host gene 16 (Lnc-RNA SNHG16) and others. Several molecular pathways are impacted. Some of them play a role in DR pathophysiology, including the PI3K-Akt signaling axis, NAD-dependent deacetylase sirtuin-1 (Sirti1), p38 mitogen-activated protein kinase (P38/mapk), transforming growth factor beta signaling (TGF-ß) and nuclear factor erythroid 2-related factor 2 (Nrf2). The way Lnc-RNAs affect diabetic retinopathy is a question of great relevance. Performing a more in-depth analysis seems to be crucial for researchers if they want to target Lnc-RNAs. New knowledge on gene regulation and biomarkers will enable investigators to develop more specialized therapies for diabetic retinopathy, particularly in the current growing context of precision medicine.

Perfiles de expresión de los genes ERG11, MDR1 y AFR1 en Cryptococcus neoformans var. grubii aislados de pacientes con HIV / Gene expression profiles of ERG11, MDR1 y AFR1 in Cryptococcus neoformans var. grubbi isolated from HIV patients

Introducción. El fluconazol es el antifúngico más utilizado para la prevención y el tratamiento de infecciones causadas por el género Cryptococcus, agente etiológico de la criptococosis. La resistencia al fluconazol en los aislamientos de Cryptoccocus neoformans puede hacer fracasar el tratamiento y generar recaídas de la infección. Objetivo. Evaluar los perfiles de expresión de los genes AFR1, MDR1 y ERG11 en aislamientos clínicos de C. neoformans var. grubii, durante la respuesta in vitro a la inducción con fluconazol. Materiales y métodos. Se estudiaron 14 aislamientos de C. neoformans var. grubii provenientes de pacientes con HIV, de los cuales 6 eran sensibles al fluconaol y 8 presentaban sensibilidad disminuida. Los niveles de expresión de los genes ERG11, AFR1 y MDR1 se determinaron mediante PCR en tiempo real. Resultados. Los aislamientos resistentes al fluconazol mostraron sobreexpresión de los genes AFR1 y MDR1, mientras que la expresión de los fenotipos de resistencia evaluados se mantuvo homogénea en ERG11, en todos los aislamientos de C. neoformans var. grubii. Conclusiones. La sobreexpresión de los genes AFR1 y MDR1 que codifican las bombas de eflujo, contribuye a la resistencia al fluconazol en los aislamientos estudiados. Sin embargo, los patrones de resistencia que se registran en este hongo, sumado a los casos de recaídas en pacientes con HIV, no pueden atribuirse únicamente a los casos de resistencia por exposición al fármaco. Otros mecanismos podrían también estar involucrados en este fenómeno, como la resistencia emergente (resistencia mediante otros genes ERG) y la heterorresistencia, los cuales deben ser estudiados en estos aislamientos.

Introduction: Fluconazole is the most used antifungal drug for prevention and treatment of Cryptococcus spp. infections, the etiological agent of cryptococcosis. Resistance to fluconazole among Cryptococcus neoformans isolates can lead to treatment failure and generate relapses. Objective: To evaluate the expression profles of the AFR1, MDR1 and ERG11 genes in C. neoformans var. grubii clinical isolates during the in vitro response to fluconazole induction. Materials and methods: Fourteen C. neoformans var. grubii isolates recovered from HIV patients were studied, in which 6 showed sensitivities to fluconazole and 8 decreased sensitivity. The expression levels of ERG11, AFR1 and MDR1 genes were determined by real-time PCR from extracted mRNA. Results: AFR1 and MDR1 genes from C. neoformans var. grubii were overexpressed in fluconazole resistant isolates, whereas ERG11 maintains homogeneous expression in all the evaluated resistance phenotypes of C. neoformans var. grubii isolates. Conclusions: The overexpression of AFR1 and MDR1 genes, which codify for efflux pumps, contributes to fluconazole resistance in the studied isolates. However, the resistance patterns in this fungus and the relapse cases in HIV patients cannot be attributed solely to the exposure to the drug. Heteroresistance and the emerging resistance (resistance through other ERG genes), might be other mechanisms involved in this phenomenon, which must be studied in these isolations.

Multiprong control of glioblastoma multiforme invasiveness: blockade of pro-inflammatory signaling, anti-angiogenesis, and homeostasis restoration.

Glioblastoma multiforme (GBM) is the most invasive type of glial tumor with poor overall survival, despite advances in surgical resection, chemotherapy, and radiation. One of the main challenges in treating GBM is related to the tumor's location, complex and heterogeneous biology, and high invasiveness. To meet the demand for oxygen and nutrients, growing tumors induce new blood vessels growth. Antibodies directed against vascular endothelial growth factor (VEGF), which promotes angiogenesis, have been developed to limit tumor growth. Bevacizumab (Avastin), an anti-VEGF monoclonal antibody, is the first approved angiogenesis inhibitor with therapeutic promise. However, it has limited efficacy, likely due to adaptive mutations in GBM, leading to overall survival compared to the standard of care in GBM patients. Molecular connections between angiogenesis, inflammation, oxidative stress pathways, and the development of gliomas have been recognized. Improvement in treatment outcomes for patients with GBM requires a multifaceted approach due to the converging dysregulation of signaling pathways. While most GBM clinical trials focus on "anti-angiogenic" modalities, stimulating inflammation resolution is a novel host-centric therapeutic avenue. The selective therapeutic possibilities for targeting the tumor microenvironment, specifically angiogenic and inflammatory pathways expand. So, a combination of agents aiming to interfere with several mechanisms might be beneficial to improve outcomes. Our approach might also be combined with other therapies to enhance sustained effectiveness. Here, we discuss Suramab (anti-angiogenic), LAU-0901 (a platelet-activating factor receptor antagonist), Elovanoid (ELV; a novel lipid mediator), and their combination as potential alternatives to contain GBM growth and invasiveness.

A Year of Living Dangerously: Challenges and Recommendations for Safely Performing Ophthalmic Surgery During the COVID-19 Pandemic, from Start to Finish.

The COVID-19 pandemic has forced all nations to take an active role in infection control incorporating recommendations and measures to control viral dissemination. The epidemiological impact is very diverse and dynamic, even within the same region. Scientific knowledge regarding SARS-CoV-2 continues to improve every day with protocols needing to be updated and adjusted on a regular basis. Ophthalmology is a medical specialty identified to be at high risk for several reasons: it has very close doctor-patient contact, the virus has been detected in tears, and the ocular surface serves as a gateway to developing the infection. We have reviewed the current information on SARS-CoV-2 in the ophthalmologic field and provide up-to-date recommendations to help create protocols that can adapt to the dynamic situation of ophthalmologic institutions, patient cases, economic situations and access to diagnostic tests. This paper outlines the main recommendations regarding the initial consultation and outpatient clinics, measures to apply in the operating room (OR), and suggestions for post-surgical controls. Triage, according to the patient's conditions and eye pathology, reduction of the time the patient is at the institution, social distancing, correct use of personal protective equipment (PPE), barrier methods, hygiene, as well as other recommendations mentioned in this document, will allow physicians to take care of the visual health of the patients while reducing the impact of the COVID-19 pandemic.

Elucidating the mechanism of action of alpha-1-antitrypsin using retinal pigment epithelium cells exposed to high glucose. Potential use in diabetic retinopathy.

BACKGROUND: Alpha-1-antitrypsin is a protein involved in avoidance of different processes that are seen in diabetic retinopathy pathogenesis. These processes include apoptosis, extracellular matrix remodeling and damage of vessel walls and capillaries. Furthermore, because of its anti-inflammatory effects, alpha-1-antitrypsin has been proposed as a possible therapeutic approach for diabetic retinopathy. Our group tested alpha-1-antitrypsin in a type 1 diabetes mouse model and observed a reduction of inflammation and retinal neurodegeneration. Thus, shedding light on the mechanism of action of alpha-1-antitrypsin at molecular level may explain how it works in the diabetic retinopathy context and show its potential for use in other retinal diseases. METHODS: In this work, we evaluated alpha-1-antitrypsin in an ARPE-19 human cell line exposed to high glucose. We explored the expression of different mediators on signaling pathways related to pro-inflammatory cytokines production, glucose metabolism, epithelial-mesenchymal transition and other proteins involved in the normal function of retinal pigment epithelium by RT-qPCR and Western Blot. RESULTS: We obtained different expression patterns for evaluated mediators altered with high glucose exposure and corrected with the use of alpha-1-antitrypsin. CONCLUSIONS: The expression profile obtained in vitro for the evaluated proteins and mRNA allowed us to explain our previous results obtained on mouse models and to hypothesize how alpha-1-antitrypsin hinder diabetic retinopathy progression on a complex network between different signaling pathways. GENERAL SIGNIFICANCE: This network helps to understand the way alpha-1-antitrypsin works in diabetic retinopathy and its scope of action.

Utilidad del gen SLCO1B1 como marcador de interés en la farmacogenómica de las estatinas / SLCO1B1 gene utility as a marker of interest in the pharmacogenomics of statins

Resumen Las enfermedades cardiovasculares son la principal causa de muerte en el mundo. Fármacos hipolipemiantes como las estatinas son la primera alternativa en la prevención primaria de eventos cardiovasculares, ictus cerebrales y procedimientos de revascularización. Estos fármacos son inhibidores de la enzima HMG-CoA reductasa, la cual regula la velocidad de la síntesis del colesterol y además aumenta la captación hepática del mismo por la vía del receptor de las LDL. El polipéptido transportador de aniones orgánicos 1B1 (OATP1B1) codificado por el gen SLCO1B1 es uno de los transportadores de captación y eflujo hepático de las estatinas. Por medio de estudios de asociación de genomas completos se han reportado diferentes SNPs dentro del gen SLCO1B1 con capacidad de reducir la captación de estatinas mediada por OATP1B1, por lo que las variaciones en la secuencia de este gen influyen en la farmacocinética y farmacodinámica de estos medicamentos, llegando a causar una condición conocida como miopatía inducida por estatinas. En la actualidad, genes que afectan las terapias cardiovasculares, así como los avances actuales en el campo de las pruebas diagnósticas basadas en la secuenciación de los mismos, ofrecen la posibilidad de revolucionar el diagnóstico y el tratamiento con el fin de validar el riesgo de predicción, pronóstico, prevención y manejo de pacientes con riesgo de enfermedades cardiovasculares, lo cual conducirá al desarrollo de nuevas formas de tratamientos médicos.

Abstract Cardiovascular diseases are the main cause of death in the world. Lipid-lowering drugs like statins are the first alternative in the primary prevention of cardiovascular events, strokes, and revascularisation procedures. These drugs are HMG-CoA reductase inhibitors, which regulate the rate of cholesterol synthesis, as well as increase its liver uptake via the LDL receptor pathway. The organic anion transporter polypeptide 1B1 (OATP1B1) coded by the solute carrier organic anion transporter 1B1 (SLCO1B1) gene is one of the hepatic influx and efflux transporters of statins. In genome-wide association studies (GWAS) different single nucleotide polymorphisms (SNPs) have been reported within the SLCO1B1 gene that are able to reduce the statin uptake mediated by OATP1B1. This suggests that the variations in the sequencing of this gene have an influence on the pharmacokinetics and pharmacodynamics of these drugs, leading to a condition known as statin-induced myopathy. Genes that affect cardiovascular treatments, as well as the current advances in diagnostic tests based on their sequencing, now offer the possibility of revolutionising their diagnosis and treatment. They could be used with the aim of validating risk prediction, prognosis, prevention, and management of patients with a risk of cardiovascular diseases, and will lead to the development of new forms of medical treatments.

Alpha-1-antitrypsin ameliorates inflammation and neurodegeneration in the diabetic mouse retina.

Diabetic retinopathy (DR) is the most common cause of blindness in the working age population. Early events of DR are accompanied by neurodegeneration of the inner retina resulting in ganglion cell loss. These findings together with reduced retinal thickness are observed within the first weeks of experimental DR. Besides, an inflammatory process is triggered in DR in which the innate immune response plays a relevant role. Alpha 1 antitrypsin (AAT), an inhibitor of serine proteases, has shown anti-inflammatory properties in several diseases. We aimed at evaluating the use of AAT to prevent the early changes induced by DR. Diabetic AAT-treated mice showed a delay on ganglion cell loss and retinal thinning. These animals showed a markedly reduced inflammatory status. AAT was able to preserve systemic and retinal TNF-α level similar to that of control mice. Furthermore, retinal macrophages found in the AAT-treated diabetic mouse exhibited M2 profile (F4/80+CD206+) together with an anti-inflammatory microenvironment. We thus demonstrated that AAT-treated mice show less retinal neurodegenerative changes and have reduced levels of systemic and retinal TNF-α. Our results contribute to shed light on the use of AAT as a possible therapeutic option in DR.

Corneal Neovascularization: A Combined Approach of Bevacizumab and Suramin Showed Increased Antiangiogenic Effect Through Downregulation of BFGF and P2X2.

PURPOSE: The objective is to analyze the antiangiogenic mechanism of suramab, a pharmaceutical compound of bevacizumab and suramin, in a rabbit model of corneal angiogenesis. MATERIAL AND METHODS: Corneal neovascularization was induced in four groups of six New Zealand White rabbits by applying a filter paper disk soaked in 1 M Na (OH) on the central cornea. Group one was treated after injury with intravenous suramab at a dose equivalent to 3 mg/kg of bevacizumab and 10 mg/kg of suramin. Group two was treated with intravenous bevacizumab (5 mg/kg). Group three was treated with 10 mg/kg of suramin while the control group received no treatment. Digital photographs were taken at days 9, 15, 21, and 35. Neovessel formation was quantified giving a 0-4 score to each quadrant according to the centripetal growth of the longest vessel (neovessel index, NVI). Animals were sacrificed at day 35. Corneas were processed for histology, immunohistochemistry, and Western-blot using primary antibodies against P2X2, basic fibroblast growth factor (bFGF), LYVE-1, PECAM-1, and vascular endothelial growth factor-A (VEGF-A). RESULTS: Suramab significantly reduced neovessel growth (mean NVI: 4.2) compared to bevacizumab (8.4), suramin (7.22), and control animals (12.2) at 35 days post-injury (p < 0.01). A lower protein expression of P2X2, bFGF, LYVE-1, PECAM-1, and VEGF-A was found in the cornea of suramab animals than in the other groups of animals. CONCLUSIONS: Joint downregulation of bFGF, P2X2, bFGF, and LYVE-1 constitutes a mechanism that induces greater and longer inhibition of corneal angiogenesis. Results might be relevant to ophthalmic care. Ocular administration of suramab is currently being investigated.

Whole exome trio sequencing reveals a novel LAMP2 mutation found in a male patient with Danon Disease: case report / Secuenciación en trío del exoma revela una nueva mutación LAMP2 encontrada en un paciente masculino con enfermedad de Danon: Reporte de caso

Abstract: Introduction: Danon syndrome was first described by Danon MJ in 1981. This rare disease is a triad consisting of dilated cardiomyopathy, myopathy and mental retardation. The etiology of the disease is associated with mutations in the LAMP2 gene on chromosome X. To date, only mutations in the LAMP2 gene have been associated with the disease. Case presentation: We present the case of a male patient who was initially suspected of being affected by Pompe disease and polymyositis without response to the treatments. He required implantation of pacemakers, and posteriorly a cardioverter defibrillator and isolation of pulmonary veins. Therefore, due to the lack of clarity in the diagnosis, endomyocardial biopsy and genetic studies were performed in order to establish the diagnosis. We found a novel mutation in the LAMP2 gene which had not been reported previously. Discussion: Danon disease is a dominant hereditary syndrome linked to the X chromosome. Danon, specifically is caused by an accumulation of glycogen in muscle cells without alterations in the enzymes responsible for its metabolism. It compromises cardiovascular, muscular and neurological systems, liver and spleen. Cardiac tissue exhibits severe fibrosis, which favors the development of supraventricular and ventricular arrhythmias. As for the diagnosis, the gold standard test is genetic analysis. The treatment is focused on the management of the manifestations that the patient presents, since there is no specific treatment. Conclusions: Danon disease requires further studies in order to obtain epidemiological data for this condition. To date, only mutations in the LAMP2 gene have been documented as the main etiology of Danon disease. We found a single nucleotide deletion in LAMP2 resulting in a frameshift mutation which is the probable cause of Danon disease in this patient.(AU)

Resumen: Introducción: El síndrome de Danon fue descrito por primera vez por MJ Danon en 1981. Esta rara enfermedad es una tríada que consiste en miocardiopatía dilatada, miopatía y retraso mental. La etiología de la enfermedad está asociada con mutaciones en el gen LAMP2 en el cromosoma X. Hasta la fecha, sólo las mutaciones en el gen LAMP2 se han asociado con la enfermedad. Presentación del caso: Presentamos el caso de un paciente masculino que inicialmente se sospechó que estaba afectado por la enfermedad de Pompe y polimiositis sin respuesta a los tratamientos. Requirió la implantación de marcapasos y, posteriormente, un desfibrilador cardioversor y el aislamiento de las venas pulmonares. Entonces, debido a la falta de claridad en el diagnóstico, se realizaron biopsias endomiocardíacas y estudios genéticos para establecer el diagnóstico. Encontramos una nueva mutación en el gen LAMP2 que no se había informado anteriormente. Discusión: La enfermedad de Danon es un síndrome hereditario dominante relacionado con el cromosoma X. Danon, específicamente es causado por una acumulación de glucógeno en las células musculares sin alteraciones en las enzimas responsables de su metabolismo. Compromete los sistemas cardiovascular, muscular y neurológico, el hígado y el bazo. El tejido cardiaco exhibe fibrosis severa, que favorece el desarrollo de arritmias supraventriculares y ventriculares. En cuanto al diagnóstico, la prueba estándar de oro es el análisis genético. El tratamiento se centra en el manejo de las manifestaciones que presenta el paciente, ya que no existe un tratamiento específico. Conclusiones: La enfermedad de Danon requiere más estudios para obtener datos epidemiológicos de esta condición. Hasta la fecha, sólo las mutaciones en el gen LAMP2 se han documentado como la principal etiología de la enfermedad de Danon. Encontramos la eliminación de un solo nucleótido en LAMP2 que resulta en una mutación de cambio de estructura que es la causa probable de la enfermedad de Danon en este paciente.(AU)

Hipercolesterolemia familiar heterocigota en manejo con anti-PCSK9 / Heterozygous familial hypercholesterolaemia being managed with anti-PCSK9

Resumen Introducción: la hipercolesterolemia familiar representa un factor de riesgo sustancial para padecer enfermedad coronaria prematura, arterial periférica y valvular. Se han descrito dos formas según su alteración genética y cigocidad, así como tres mutaciones genéticas asociadas. Pese a que el tratamiento con estatinas se considera la primera línea, algunos pacientes no alcanzan metas, de modo que se han utilizado los inhibidores del PCSK9 como nueva estrategia. Métodos y materiales: se expone el caso de una paciente de 42 años con hipercolesterolemia familiar heterocigota tratada con inhibidores del PCSK9. Se describen los criterios y estudiosgenéticos utilizados para realizar el diagnóstico, la cronología de tratamientos que recibió y los exámenes de laboratorio anteriores y posteriores al inicio del evolocumab. Adicionalmente se hace una revisión de tema acerca de la hipercolesterolemia familiar y su tratamiento con inhibidores del PCSK9. Conclusiones: la hipercolesterolemia familiar es una enfermedad que ocasiona graves consecuencias cardiovasculares. Los inhibidores del PCSK9 se han convertido en una alternativa prometedora para aquellos que no responden a las terapias convencionales. Se requieren estudios que corroboren o contradigan los beneficios y eventos adversos encontrados hasta el momento en que los pacientes se someten a estas nuevas terapias para así ofrecer un tratamiento ideal y oportuno.

Abstract Introduction: Familial hypercholesterolaemia is a substantial risk factor for suffering premature coronary, peripheral arterial, and valular disease. There are two forms described, depending on their genetics and zygosity, as well as three associated genetic mutations. Although treatment with statins is considered first line, some patients do not reach targets, as such that that PCSK9 inhibitors have been used as a new strategy. Materials and method: A case is presented of a 42 year-old patient with heterozygous familial hypercholesterolaemia treated with PCSK9 inhibitors. The criteria and genetic studies used to make a diagnosis are described, as well as the chronology of the treatments that have been received and the laboratory results before and after starting with evolocumab. A review has also been made of the subject of familial hypercholesterolaemia and its treatment with PCSK9 inhibitors. Conclusions: Familial hypercholesterolaemia is a diseases that may have serious cardiovascular consequences. PCSK9 inhibitors have become a promising alternative for those who do not respond to conventional therapies. Studies are required that can corroborate or contradict the benefits and adverse effects found up until now in patients subjected to these new therapies in order to offer an ideal and appropriate treatment.

The Dynamic Genome and Transcriptome of the Human Fungal Pathogen Blastomyces and Close Relative Emmonsia.

Three closely related thermally dimorphic pathogens are causal agents of major fungal diseases affecting humans in the Americas: blastomycosis, histoplasmosis and paracoccidioidomycosis. Here we report the genome sequence and analysis of four strains of the etiological agent of blastomycosis, Blastomyces, and two species of the related genus Emmonsia, typically pathogens of small mammals. Compared to related species, Blastomyces genomes are highly expanded, with long, often sharply demarcated tracts of low GC-content sequence. These GC-poor isochore-like regions are enriched for gypsy elements, are variable in total size between isolates, and are least expanded in the avirulent B. dermatitidis strain ER-3 as compared with the virulent B. gilchristii strain SLH14081. The lack of similar regions in related species suggests these isochore-like regions originated recently in the ancestor of the Blastomyces lineage. While gene content is highly conserved between Blastomyces and related fungi, we identified changes in copy number of genes potentially involved in host interaction, including proteases and characterized antigens. In addition, we studied gene expression changes of B. dermatitidis during the interaction of the infectious yeast form with macrophages and in a mouse model. Both experiments highlight a strong antioxidant defense response in Blastomyces, and upregulation of dioxygenases in vivo suggests that dioxide produced by antioxidants may be further utilized for amino acid metabolism. We identify a number of functional categories upregulated exclusively in vivo, such as secreted proteins, zinc acquisition proteins, and cysteine and tryptophan metabolism, which may include critical virulence factors missed before in in vitro studies. Across the dimorphic fungi, loss of certain zinc acquisition genes and differences in amino acid metabolism suggest unique adaptations of Blastomyces to its host environment. These results reveal the dynamics of genome evolution and of factors contributing to virulence in Blastomyces.

Transglutaminase binding fusion protein linked to SLPI reduced corneal inflammation and neovascularization.

BACKGROUND: To study the effect of topical administration of a fusion protein (PF-MC) made up of N-terminal portion of the protease inhibitor Trappin-2 (which is a substrate of transglutaminasa-2) and SLPI (protein with anti-inflammatory, anti-bacterial and anti-viral ability), in an animal model of corneal inflammation and angiogenesis. METHODS: An alkali injury was produced with a filter paper of 3 mm with 1 N NaOH during 40 seconds on the right cornea of 36 male Sprague Dawley rats, under general anesthesia. Animals were divided into three groups according to treatment. Group 1 was treated with 10 ul of PF-MC (200 ug/ml; n = 12), Group 2, with 10 ul of SLPI (200 ug/ml; n = 12) and Group 3 was treated with buffer (10 ul; n = 12) topically administered four times a day for up to 7 days. Half of the animals were sacrificed at day 3 before making a re-epithelialization time analysis with fluorescein staining at 18 and 24 hours. In the remaining animals corneal opacity was studied and digital photographs were taken at day 7 before doing euthanasia. Eyes were processed for histology and immunofluorescence. RESULTS: Corneal ulcerated area was significantly lower in PF-MC treated animals compared to SLPI and buffer-treated animals at 18 hours and 24 hours postinjury. A clear cornea and fundus red reflex was only found among PF-MC treated animals. Histological analysis revealed a stratified corneal epithelium with at least three layers in all PF-MC animals at day 7. In this group there was a reduced number of PMNs in the corneal stroma at 3 and 7 days of follow-up. Besides, corneal neovascularization was much more extended in SLPI and Buffer animals than in animals treated with PF-MC. CONCLUSIONS: The binding of SLPI with Cementoin to transglutaminase seems to be an effective strategy to treat corneal inflammation and angiogenesis.

Genome update of the dimorphic human pathogenic fungi causing paracoccidioidomycosis.

Paracoccidiodomycosis (PCM) is a clinically important fungal disease that can acquire serious systemic forms and is caused by the thermodimorphic fungal Paracoccidioides spp. PCM is a tropical disease that is endemic in Latin America, where up to ten million people are infected; 80% of reported cases occur in Brazil, followed by Colombia and Venezuela. To enable genomic studies and to better characterize the pathogenesis of this dimorphic fungus, two reference strains of P. brasiliensis (Pb03, Pb18) and one strain of P. lutzii (Pb01) were sequenced [1]. While the initial draft assemblies were accurate in large scale structure and had high overall base quality, the sequences had frequent small scale defects such as poor quality stretches, unknown bases (N's), and artifactual deletions or nucleotide duplications, all of which caused larger scale errors in predicted gene structures. Since assembly consensus errors can now be addressed using next generation sequencing (NGS) in combination with recent methods allowing systematic assembly improvement, we re-sequenced the three reference strains of Paracoccidioides spp. using Illumina technology. We utilized the high sequencing depth to re-evaluate and improve the original assemblies generated from Sanger sequence reads, and obtained more complete and accurate reference assemblies. The new assemblies led to improved transcript predictions for the vast majority of genes of these reference strains, and often substantially corrected gene structures. These include several genes that are central to virulence or expressed during the pathogenic yeast stage in Paracoccidioides and other fungi, such as HSP90, RYP1-3, BAD1, catalase B, alpha-1,3-glucan synthase and the beta glucan synthase target gene FKS1. The improvement and validation of these reference sequences will now allow more accurate genome-based analyses. To our knowledge, this is one of the first reports of a fully automated and quality-assessed upgrade of a genome assembly and annotation for a non-model fungus.

Diabetic retinopathy: could the alpha-1 antitrypsin be a therapeutic option?

Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM) leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF) to induce the angiogenesis process. Alpha-1 antitrypsin (AAT) is the most important circulating inhibitor of serine proteases (SERPIN). Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3) and plasminogen activator (PAI). AAT modulates the effect of protease-activated receptors (PARs) during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs). Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO) by nitric oxide sintase (NOS) inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.

Diabetic retinopathy: could the alpha-1 antitrypsin be a therapeutic option?

Diabetic retinopathy is one of the most important causes of blindness. The underlying mechanisms of this disease include inflammatory changes and remodeling processes of the extracellular-matrix (ECM) leading to pericyte and vascular endothelial cell damage that affects the retinal circulation. In turn, this causes hypoxia leading to release of vascular endothelial growth factor (VEGF) to induce the angiogenesis process. Alpha-1 antitrypsin (AAT) is the most important circulating inhibitor of serine proteases (SERPIN). Its targets include elastase, plasmin, thrombin, trypsin, chymotrypsin, proteinase 3 (PR-3) and plasminogen activator (PAI). AAT modulates the effect of protease-activated receptors (PARs) during inflammatory responses. Plasma levels of AAT can increase 4-fold during acute inflammation then is so-called acute phase protein (APPs). Individuals with low serum levels of AAT could develop disease in lung, liver and pancreas. AAT is involved in extracellular matrix remodeling and inflammation, particularly migration and chemotaxis of neutrophils. It can also suppress nitric oxide (NO) by nitric oxide sintase (NOS) inhibition. AAT binds their targets in an irreversible way resulting in product degradation. The aim of this review is to focus on the points of contact between multiple factors involved in diabetic retinopathy and AAT resembling pleiotropic effects that might be beneficial.

Retinal upregulation of inflammatory and proangiogenic markers in a model of neonatal diabetic rats fed on a high-fat-diet.

BACKGROUND: The contemporary peak of diabetes seems to be related to obesity, sedentary lifestyle and diet. Diabetic retinopathy is the most leading cause of blindness in adulthood in industrialized countries. Our purpose was to evaluate the effect of a high-fat-diet (HFD) on the retina of diabetic rats. METHODS: Two groups of Wistar rats were injected with streptozotocin (STZ) two days after birth using 45 and 90 mg/kg, respectively. At 8 weeks the group on lower doses started to be fed on a HFD. Animals were sacrificed at 37 weeks of diabetes. A control group was made up of non-diabetic rats. Retinal flat mounts were examined using the trypsin digestion technique. Pericytes counts were compared between diabetic and control rats. Cross retinal sections were analyzed by histological techniques and immunohistochemistry and immunofluorescent technique. Primary antibodies against inflammatory and proangiogenic mediators such as RAGE, GFAP, 5-LO, VEGF and TNF-α were used for immunohistochemistry and Western Blot (WB) analyses. RESULTS: In the two diabetic groups we observed GFAP-positive cells with a morphology and spatial organization similar to those seen in Müller cells. Both diabetic groups had a significantly lower number of pericytes than non-diabetic animals.Increased retinal immunoreactivity of GFAP, RAGE, TNF-α, VEGF and 5-LO was seen in diabetic animals fed on HFD compared to the other groups of animals. WB analysis revealed a higher expression of 5-LO, VEGF, TNF-α and RAGE in the retina of diabetic rats on HFD than in controls and diabetics fed on a normal diet. The percentage of RAGE-stained ganglion cells and ganglion cells was found to be significantly lower in animals on a HFD than in the other animals. CONCLUSIONS: Diabetic animals fed on a HFD showed an increased upregulation of inflammatory and proangiogenic markers. This animal model may be useful to study mechanisms of diabetic retinopathy and therapeutic targets.

Suramab, a novel antiangiogenic agent, reduces tumor growth and corneal neovascularization.

PURPOSE: Oncological and ophthalmological diseases are increasingly treated with antiangiogenic agents. These agents have different intensities and duration of effects that should be considered to choose the most suitable therapy. Our purpose was to evaluate the synergistic effect of two drugs, jointly administered as a pharmaceutical compound, in two animal models. METHODS: Corneal neovascularization was induced in three groups of nine white New Zealand rabbits, applying a filter paper disk soaked in 1 M NaOH on the central cornea (Ormerod et al., Invest Ophthalmol Vis Sci 30:2148-2153, 1989). Group one was treated immediately after injury with intravenous Suramab, compound of Bevacizumab + Suramin, and group two with intravenous Bevacizumab. A third group of non-treated rabbits was included as control group. Digital photographs were taken at days 9, 15, 21, and 35. Neovessel index (NVI) was calculated using the Image J Program. Neovessels formation was quantified and given a score from 0 to 4 to each quadrant according to the centripetal growth of the longest vessel. Colorectal animal model: 6- to 8-week-old male BALB/c mice were inoculated with cancer cells. Seven days after tumor inoculation, four groups of BALB/c mice were treated with intravenous Bevacizumab (n = 9); intravenous Suramin (n = 10); intravenous Suramab (n = 10); and intravenous saline solution (n = 4). Tumor growth was assessed twice weekly by caliper measurement. RESULTS: The NVI was remarkably inferior in the group of rabbits treated with intravenous Suramab compared with controls after 35 days of follow-up. A greater inhibitory effect was obtained with Suramab compared to that obtained with Bevacizumab. Suramab significantly reduced tumor volume and prolonged survival of mice compared to controls. CONCLUSIONS: Suramab strongly reduced neovascularization in a rabbit model of corneal angiogenesis and induced a potent antitumoral effect in mice.

One-year follow-up of epithelial corneal cell sheet allografts mounted on platelet poor plasma in rabbits.

PURPOSE: To evaluate the usefulness of epithelial corneal sheets mounted on platelet poor plasma (PPP) for allograft transplantation of rabbits with total limbal stem cell deficiency (LSCD) and to prove its efficacy at 1 year after surgery. METHODS: LSCD was induced in 21 female rabbits by mechanical keratectomy. To configure the grafts, limbal biopsies were taken from male rabbits and cells were cultured on a fibroblast feeder layer grown on clotted autologous PPP. After keratectomy, grafts were sutured over the stroma. Control groups consisted of no implant or an implant of clotted PPP. Rabbits were euthanized at 3 and 12 months. Corneas and cultured sheets were processed for histopathology and immunohistochemistry (K3/12 and K19). Gender analysis was performed at 4 and 7 months. RESULTS: One rabbit had endophthalmitis, and another died of no apparent cause. The rest of the animals treated had no inflammation, showed a stratified epithelium, keratin 3/12 expression, and no expression of keratin 19. At 1 year, seven of eight rabbits showed no LSCD or corneal rejection signs. Y chromosomes were detected at 4 and 7 months postoperatively. All controls showed LSCD signs, erratic epithelium, and minimal cell differentiation; they revealed a slight expression of K3/12 and an expression of K19 in patchy patterns. CONCLUSIONS: Allografts contributed to restoring a healthy eye surface without signs of graft rejection. This technique seems to be a promising procedure for bilateral ocular surface diseases and may be useful for new therapeutic strategies.

Advances in corneal stem-cell transplantation in rabbits with severe ocular alkali burns.

PURPOSE: To evaluate the efficacy of autologous corneal epithelial sheet implantation in restoring transparency of rabbit corneas severely injured by alkaline and the effect of photocoagulation in arresting corneal neovessel ingrowth. SETTING: Ophthalmology Department, School of Biomedical Sciences, Universidad Austral, Buenos Aires, Argentina. METHODS: Limbal stem-cell deficiency (LSCD) was induced in 14 rabbits by alkali burns. A limbal cell biopsy was done in the contralateral eye, and the cells were cultured on a fibroblast feeder layer grown on autologous clotted platelet-poor plasma or commercial fibrin for 21 days. Anterior keratectomy was followed by suturing corneal cell sheets over the stroma. If regrowth of vessels occurred, argon laser photocoagulation was applied to them. Rabbits were killed at 30, 60, 90, 180, and 360 days and the corneas processed for histopathology and inmunohistochemistry. RESULTS: A small (2.5 mm(2)) limbal biopsy achieved stem-cell replication in vitro. Corneal clarity and epithelial defects evolved with a trend toward improvement. There was a significant reduction in corneal neovascularization. Histology showed a multilayered stratified epithelium including several epithelial-like cells with clear cytoplasm in the deepest part. There were no signs of intraepithelial mucin cells on the implanted corneas. Immunohistochemical results showed expression of cytokeratins 3 and 12 in the central corneal epithelium and an absence of cytokeratin 19. CONCLUSIONS: Autologous limbal epithelial cell transplantation improved the corneal surface in eyes with LSCD. Photocoagulation of neovessel ingrowth was effective over the 1-year follow-up. Results may facilitate the application of this technique in patients.