Alteraciones óseas asociadas con Diabetes mellitus: mecanismos patogénicos y estrategias de tratamiento con alendronato

Objetivos generales: Investigar las alteraciones óseas que se desarrollan en un modelo murino de diabetes leve. Investigar el efecto de los AGEs sobre células progenitoras de médula ósea (CPMO) en cultivo, así como el rol del alendronato sobre dichos efectos. Objetivos específicos: 1. Analizar el efecto de AGEs y alendronato sobre la diferenciación de CPMO al fenotipo osteoblástico, adipogénico y condrogénico en cultivo. 2. Investigar la capacidad de diferenciación osteogénica, adipogénica y condrogénica de CPMO provenientes de ratas controles o diabéticas, tratadas o no con alendronato (efecto ex-vivo del alendronato sobre CPMO). 3. Investigar el efecto del tratamiento in vivo con alendronato sobre las alteraciones asociadas con la diabetes, en la microarquitectura de huesos largos.Facultad de Ciencias Exacta

Alendronate Can Improve Bone Alterations in Experimental Diabetes by Preventing Antiosteogenic, Antichondrogenic, and Proadipocytic Effects of AGEs on Bone Marrow Progenitor Cells

Bisphosphonates such as alendronate are antiosteoporotic drugs that inhibit the activity of bone-resorbing osteoclasts and secondarily promote osteoblastic function. Diabetes increases bone-matrix-associated advanced glycation end products (AGEs) that impair bone marrow progenitor cell (BMPC) osteogenic potential and decrease bone quality. Here we investigated the in vitro effect of alendronate and/or AGEs on the osteoblastogenic, adipogenic, and chondrogenic potential of BMPC isolated from nondiabetic untreated rats. We also evaluated the in vivo effect of alendronate (administered orally to rats with insulin-deficient Diabetes) on long-bone microarchitecture and BMPC multilineage potential. In vitro, the osteogenesis (Runx2, alkaline phosphatase, type 1 collagen, and mineralization) and chondrogenesis (glycosaminoglycan production) of BMPC were both decreased by AGEs, while coincubation with alendronate prevented these effects. The adipogenesis of BMPC (PPARγ, intracellular triglycerides, and lipase) was increased by AGEs, and this was prevented by coincubation with alendronate. In vivo, experimental Diabetes (a) decreased femoral trabecular bone area, osteocyte density, and osteoclastic TRAP activity; (b) increased bone marrow adiposity; and (c) deregulated BMPC phenotypic potential (increasing adipogenesis and decreasing osteogenesis and chondrogenesis). Orally administered alendronate prevented all these Diabetes-induced effects on bone. Thus, alendronate could improve bone alterations in diabetic rats by preventing the antiosteogenic, antichondrogenic, and proadipocytic effects of AGEs on BMPC.Laboratorio de Investigación en Osteopatías y Metabolismo Minera

Alendronate Can Improve Bone Alterations in Experimental Diabetes by Preventing Antiosteogenic, Antichondrogenic, and Proadipocytic Effects of AGEs on Bone Marrow Progenitor Cells

Bisphosphonates such as alendronate are antiosteoporotic drugs that inhibit the activity of bone-resorbing osteoclasts and secondarily promote osteoblastic function. Diabetes increases bone-matrix-associated advanced glycation end products (AGEs) that impair bone marrow progenitor cell (BMPC) osteogenic potential and decrease bone quality. Here we investigated the in vitro effect of alendronate and/or AGEs on the osteoblastogenic, adipogenic, and chondrogenic potential of BMPC isolated from nondiabetic untreated rats. We also evaluated the in vivo effect of alendronate (administered orally to rats with insulin-deficient Diabetes) on long-bone microarchitecture and BMPC multilineage potential. In vitro, the osteogenesis (Runx2, alkaline phosphatase, type 1 collagen, and mineralization) and chondrogenesis (glycosaminoglycan production) of BMPC were both decreased by AGEs, while coincubation with alendronate prevented these effects. The adipogenesis of BMPC (PPARγ, intracellular triglycerides, and lipase) was increased by AGEs, and this was prevented by coincubation with alendronate. In vivo, experimental Diabetes (a) decreased femoral trabecular bone area, osteocyte density, and osteoclastic TRAP activity; (b) increased bone marrow adiposity; and (c) deregulated BMPC phenotypic potential (increasing adipogenesis and decreasing osteogenesis and chondrogenesis). Orally administered alendronate prevented all these Diabetes-induced effects on bone. Thus, alendronate could improve bone alterations in diabetic rats by preventing the antiosteogenic, antichondrogenic, and proadipocytic effects of AGEs on BMPC.Laboratorio de Investigación en Osteopatías y Metabolismo Minera

In silico Guided Drug Repurposing: Discovery of New Competitive and Non-competitive Inhibitors of Falcipain-2

Malaria is among the leading causes of death worldwide. The emergence of Plasmodium falciparum resistant strains with reduced sensitivity to the first line combination therapy and suboptimal responses to insecticides used for Anopheles vector management have led to renewed interest in novel therapeutic options. Here, we report the development and validation of an ensemble of ligand-based computational models capable of identifying falcipain-2 inhibitors, and their subsequent application in the virtual screening of DrugBank and Sweetlead libraries. Among four hits submitted to enzymatic assays, two (odanacatib, an abandoned investigational treatment for osteoporosis and bone metastasis, and the antibiotic methacycline) confirmed inhibitory effects on falcipain-2, with Ki of 98.2 nM and 84.4 μM. Interestingly, Methacycline proved to be a non-competitive inhibitor (α = 1.42) of falcipain-2. The effects of both hits on falcipain-2 hemoglobinase activity and on the development of P. falciparum were also studied.Fil: Alberca, Lucas Nicolás. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Chuguransky, Sara Rocío. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Alvarez, Cora Lilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Talevi, Alan. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; ArgentinaFil: Salas Sarduy, Emir. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas; Argentin

Application of Machine Learning Approaches to Identify New Anticonvulsant Compounds Active in the 6 Hz Seizure Model

Epilepsy is the second most common chronic brain disorder, affecting 65 million people worldwide. According to the NIH’s Epilepsy Therapy Screening Program, evaluation of potential new antiepileptic drug candidates begins with assessment of their protective effects in two acute seizure models in mice, the Maximal Electroshock Seizure test and the 6 Hz test. The latter elicits partial seizures through an electrical stimulus of 44 mA, at which many clinically established anti-seizure drugs do not suppress seizures. The inclusion of this “high-hurdle” acute seizure assay at the initial stage of the drug identification phase is intended to increase the probability that agents with improved efficacy will be detected. In this work, we have used machine learning approximations to develop in silico models capable of identifying novel anticonvulsant drugs with protective effects in the 6 Hz seizure model. Linear classifiers based on Dragon conformation-independent descriptors were generated through an in-house routine in R environment and validated through standard validation procedures. They were later combined through different ensemble learning schemes. The best ensemble comprised the 29 best-performing models combined using the MIN operator. With the objective of finding new drug repurposing opportunities (i.e. identifying second or further therapeutic indications, in our case anticonvulsant activity, in existing drugs), such model ensemble was applied in a virtual screening campaign of DrugBank and Sweetlead databases. 28 approved drugs were identified as potential protective agents in the 6 Hz model. The present study constitutes an example of the use of machine learning approximations to systematically guide drug repurposing projects.Laboratorio de Investigación y Desarrollo de Bioactivo

Insulin-deficient diabetes-induced bone microarchitecture alterations are associated with a decrease in the osteogenic potential of bone marrow progenitor cells: Preventive effects of metformin

Aims: Diabetes mellitus is associated with metabolic bone disease and increased lowimpact fractures. The insulin-sensitizer metformin possesses in vitro, in vivo and ex vivo osteogenic effects, although this has not been adequately studied in the context of diabetes. We evaluated the effect of insulin-deficient diabetes and/or metformin on bone microarchitecture, on osteogenic potential of bone marrow progenitor cells (BMPC) and possible mechanisms involved. Methods: Partially insulin-deficient diabetes was induced in rats by nicotinamide/streptozotocin-injection, with or without oral metformin treatment. Femoral metaphysis microarchitecture, ex vivo osteogenic potential of BMPC, and BMPC expression of Runx-2, PPARg and receptor for advanced glycation endproducts (RAGE) were investigated. Results: Histomorphometric analysis of diabetic femoral metaphysis demonstrated a slight decrease in trabecular area and a significant reduction in osteocyte density, growth plate height and TRAP (tartrate-resistant acid phosphatase) activity in the primary spongiosa. BMPC obtained from diabetic animals showed a reduction in Runx-2/PPARg ratio and in their osteogenic potential, and an increase in RAGE expression. Metformin treatment prevented the diabetes-induced alterations in bone micro-architecture and BMPC osteogenic potential. Conclusion: Partially insulin-deficient diabetes induces deleterious effects on long-bone micro-architecture that are associated with a decrease in BMPC osteogenic potential, which could be mediated by a decrease in their Runx-2/PPARg ratio and up-regulation of RAGE. These diabetes-induced alterations can be totally or partially prevented by oral administration of metformin.Facultad de Ciencias ExactasLaboratorio de Investigación en Osteopatías y Metabolismo Minera

Computational strategies to combat COVID-19: useful tools to accelerate SARS-CoV-2 and coronavirus research

SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is a novel virus of the family Coronaviridae. The virus causesthe infectious disease COVID-19. The biology of coronaviruses has been studied for many years. However, bioinformaticstools designed explicitly for SARS-CoV-2 have only recently been developed as a rapid reaction to the need for fast detection,understanding and treatment of COVID-19. To control the ongoing COVID-19 pandemic, it is of utmost importance to getinsight into the evolution and pathogenesis of the virus. In this review, we cover bioinformatics workflows and tools for theroutine detection of SARS-CoV-2 infection, the reliable analysis of sequencing data, the tracking of the COVID-19 pandemicand evaluation of containment measures, the study of coronavirus evolution, the discovery of potential drug targets anddevelopment of therapeutic strategies. For each tool, we briefly describe its use case and how it advances researchspecifically for SARS-CoV-2.Fil: Hufsky, Franziska. Friedrich Schiller University Jena; AlemaniaFil: Lamkiewicz, Kevin. Friedrich Schiller University Jena; AlemaniaFil: Almeida, Alexandre. the Wellcome Sanger Institute; Reino UnidoFil: Aouacheria, Abdel. Centre National de la Recherche Scientifique; FranciaFil: Arighi, Cecilia. Biocuration and Literature Access at PIR; Estados UnidosFil: Bateman, Alex. European Bioinformatics Institute. Head of Protein Sequence Resources; Reino UnidoFil: Baumbach, Jan. Universitat Technical Zu Munich; AlemaniaFil: Beerenwinkel, Niko. Universitat Technical Zu Munich; AlemaniaFil: Brandt, Christian. Jena University Hospital; AlemaniaFil: Cacciabue, Marco Polo Domingo. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Chuguransky, Sara Rocío. European Bioinformatics Institute; Reino Unido. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Drechsel, Oliver. Robert Koch-Institute; AlemaniaFil: Finn, Robert D.. Biocurator for Pfam and InterPro databases; Reino UnidoFil: Fritz, Adrian. Helmholtz Centre for Infection Research; AlemaniaFil: Fuchs, Stephan. Robert Koch-Institute; AlemaniaFil: Hattab, Georges. University Marburg; AlemaniaFil: Hauschild, Anne Christin. University Marburg; AlemaniaFil: Heider, Dominik. University Marburg; AlemaniaFil: Hoffmann, Marie. Freie Universität Berlin; AlemaniaFil: Hölzer, Martin. Friedrich Schiller University Jena; AlemaniaFil: Hoops, Stefan. University of Virginia; Estados UnidosFil: Kaderali, Lars. University Medicine Greifswald; AlemaniaFil: Kalvari, Ioanna. European Bioinformatics Institute; Reino UnidoFil: von Kleist, Max. Robert Koch-Institute; AlemaniaFil: Kmiecinski, Renó. Robert Koch-Institute; AlemaniaFil: Kühnert, Denise. Max Planck Institute for the Science of Human History; AlemaniaFil: Lasso, Gorka. Albert Einstein College of Medicine; Estados UnidosFil: Libin, Pieter. Hasselt University; BélgicaFil: List, Markus. Universitat Technical Zu Munich; AlemaniaFil: Löchel, Hannah F.. University Marburg; Alemani

Metabolismo del hemo - porfirias

El hemo es un anillo tetrapirrolico perteneciente al grupo de las metaloporfirinas y constituyentede muchas proteínas celulares que realizan funciones de transporte y almacenamiento deoxígeno (hemoglobina, mioglobina), de aquellas que transportan electrones (Citocromos de lascadenas respiratorias de la mitocondria) y de proteínas que participan en reacciones del tipooxidación-reducción (por ejemplo citocromo P450). El hígado y la médula ósea son los principalesórganos donde se sintetiza el hemo, principalmente para la síntesis de citocromo p450 y hemoglobina,respectivamente. Sin embargo, también se sintetiza en casi todas las células debido aque el grupo hemo es importante para otras proteínas como ser catalasa, peroxidasa, triptofanopirrolasa, prostaglandina endoperóxido sintasa y guanilato ciclasa. En otros organismos, otrametaloporfirina de gran importancia es la clorofila, la cual, en lugar de quelar un átomo de Fe seencuentra quelando un átomo de Mg. De hecho, en 1930, Hans Fischer, describio a las porfirinascomo un compuesto que hace verde a las hierbas y roja a la sangre.Las porfirinas son tetrapirroles macrociclos de 4 anillos pirrólicos, unidos a su vez por cuatropuentes metenos (Fig 15.1). Además de ser compuestos cíclicos, poseen una cantidad de doblesenlaces conjugados que le otorgan estabilidad y características fotofísicas particulares.Fil: Chuguransky, Sara Rocío. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; ArgentinaFil: Fernández, Juan Manuel. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Departamento de Ciencias Biológicas. Laboratorio de Investigación en Osteospatías y Metabolismo Mineral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata; Argentin

Alendronate Can Improve Bone Alterations in Experimental Diabetes by Preventing Antiosteogenic, Antichondrogenic, and Proadipocytic Effects of AGEs on Bone Marrow Progenitor Cells

Bisphosphonates such as alendronate are antiosteoporotic drugs that inhibit the activity of bone-resorbing osteoclasts and secondarily promote osteoblastic function. Diabetes increases bone-matrix-associated advanced glycation end products (AGEs) that impair bone marrow progenitor cell (BMPC) osteogenic potential and decrease bone quality. Here we investigated the in vitro effect of alendronate and/or AGEs on the osteoblastogenic, adipogenic, and chondrogenic potential of BMPC isolated from nondiabetic untreated rats. We also evaluated the in vivo effect of alendronate (administered orally to rats with insulindeficient Diabetes) on long-bone microarchitecture and BMPC multilineage potential. In vitro, the osteogenesis (Runx2, alkaline phosphatase, type 1 collagen, and mineralization) and chondrogenesis (glycosaminoglycan production) of BMPC were both decreased by AGEs, while coincubation with alendronate prevented these effects.The adipogenesis of BMPC (PPAR��, intracellular triglycerides, and lipase) was increased by AGEs, and this was prevented by coincubation with alendronate. In vivo, experimental Diabetes (a) decreased femoral trabecular bone area, osteocyte density, and osteoclastic TRAP activity; (b) increased bone marrow adiposity; and (c) deregulated BMPC phenotypic potential (increasing adipogenesis and decreasing osteogenesis and chondrogenesis). Orally administered alendronate prevented all these Diabetes-induced effects on bone. Thus, alendronate could improve bone alterations in diabetic rats by preventing the antiosteogenic, antichondrogenic, and proadipocytic effects of AGEs on BMPC

Discovery of novel falcipain 2 inhibitors by in silico guided drug repositioning

Malaria is a life-threatening condition that continues being one of global leading causes of death worldwide, being themain cause of death globally in the 5-14 year-old population. The disease is caused by parasites from the Plasmodiumgenre. The emergence of Plasmodium falciparum resistant strains with reduced sensitivity to the first linecombination therapy have led to renewed interest in novel therapeutic options. In this work, our objective was theidentification of novel Falcipan-2 (FP2) inhibitors through the application of an in silico approach and the subsequentin vitro evaluation of the emerging hits. FP2 is a key cysteine protease in the life cycle of P. falciparum constituting apromising target in the search for novel therapies due to their significant hemoglobinase capacity.We have developed a ligand-based model ensemble capable of recognizing FP2 inhibitors from non-inhibitors. Thisensemble has showed a powerful ability for the identification of FP2 inhibitors. The ensemble was applied in a virtualscreening campaign of DrugBank database to identify approved drugs with FP2 inhibitory activity. 4 hits wereacquired and tested against recombinant FP2 using a fluorogenic continuous enzymatic assay under balanced assayconditions ([S]0/KM=1). The reversibility of the interaction, mode of inhibition and Ki were further investigated forvalidated hits. Two drugs, Methacycline and Odanacatib, showed dose-dependent inhibition of FP2. Although bothinhibitors showed reversible interactions with FP2, the compounds displayed different inhibition mechanisms. Doseresponseanalysis at growing substrate concentrations indicated that Odanacatib is a competitive inhibitor of FP2(Ki=98.2 nM), whereas Methacycline displayed non-competitive behaviour (Ki=84.4 μM; α =1.42) being to our bestknowledge the first report of the inhibition of plasmodial cysteine proteases by a tetracycline derivative in a noncompetitivemanner. To access the impact of Methacycline and Odanacatib on the intracellular parasite?sdevelopment, parasite trophozoite forms were treated with the compounds for 48h and the parasitemia was analyzedby light microscopy. Treatment of infected erythrocytes with the compounds caused inhibition in a dose-dependentmanner. These results demonstrate the utility of the in silico approach, since we could find two FP2 inhibitors withantiplasmodial activity with a minimal investment of time and money.Fil: Alberca, Lucas Nicolás. Universidad Nacional de La Plata. Facultad de Ciencas Exactas. Laboratorio de Investigación y Desarrollo de Bioactivos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Ingeniería Genética y Biología Molecular "Dr. Héctor N. Torres"; ArgentinaFil: Chuguransky, Sara Rocío. Universidad Nacional de La Plata. Facultad de Ciencas Exactas. Laboratorio de Investigación y Desarrollo de Bioactivos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Alvarez, Cora Lilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Salas Sarduy, Emir. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús). Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. Instituto de Investigaciones Biotecnológicas "Dr. Raúl Alfonsín" (sede Chascomús); ArgentinaFil: Talevi, Alan. Universidad Nacional de La Plata. Facultad de Ciencas Exactas. Laboratorio de Investigación y Desarrollo de Bioactivos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaConference on drug discovery & developmentDundeeReino UnidoCentre for Anti-Infectives ResearchUniversity of Dunde