The Use of Amniotic Membrane in the Management of Complex Chronic Wounds

Chronic wounds do not follow the usual wound healing process; instead, they are stuck in the inflammatory or proliferative phase. This is particularly evident in large, massive wounds with considerable tissue loss, which become senescent and do not epithelialize. In these wounds, we need to remove all the factors that prevent or delay normal wound healing. After that, soft tissue granulation is stimulated by local negative pressure therapy. Lastly, after the granulation is completed, the epithelialization process must be activated. Although a plethora of wound dressings and devices are available, chronic wounds persist as a unresolved medical concern. We have been using frozen amniotic membrane (AM) to treat this type of wounds with good results. Our studies have shown that AM is able to induce epithelialization in large wounds that were unable to epithelialize. AM induces several signaling pathways involved in cell migration and/or proliferation. Among those, we can highlight the mitogen‐activated protein kinase (MAPK) and Jun N‐terminal kinase (JNK) signaling pathways. Additionally, AM is able to selectively antagonise the anti-proliferative effect of TGFß by modifying its genetic program on keratinocytes. The combined effect of AM on keratinocytes, promoting cell proliferation/migration and antagonising TGFß-effect, is the perfect combination allowing chronic wounds to progress into epithelialization

Acid ceramidase improves mitochondrial function and oxidative stress in Niemann-Pick type C disease by repressing STARD1 expression and mitochondrial cholesterol accumulation.

Niemann-Pick type C (NPC) disease, a lysosomal storage disorder caused by defective NPC1/NPC2 function, results in the accumulation of cholesterol and glycosphingolipids in lysosomes of affected organs, such as liver and brain. Moreover, increase of mitochondrial cholesterol (mchol) content and impaired mitochondrial function and GSH depletion contribute to NPC disease. However, the underlying mechanism of mchol accumulation in NPC disease remains unknown. As STARD1 is crucial in intramitochondrial cholesterol trafficking and acid ceramidase (ACDase) has been shown to regulate STARD1, we explored the functional relationship between ACDase and STARD1 in NPC disease. Liver and brain of Npc1−/− mice presented a significant increase in mchol levels and STARD1 expression. U18666A, an amphiphilic sterol that inhibits lysosomal cholesterol efflux, increased mchol levels in hepatocytes from Stard1f/f mice but not Stard1ΔHep mice. We dissociate the induction of STARD1 expression from endoplasmic reticulum stress, and establish an inverse relationship between ACDase and STARD1 expression and LRH-1 levels. Hepatocytes from Npc1+/+ mice treated with U18666A exhibited increased mchol accumulation, STARD1 upregulation and decreased ACDase expression, effects that were reversed by cholesterol extraction with 2-hydroxypropyl-β-cyclodextrin. Moreover, transfection of fibroblasts from NPC patients with ACDase, decreased STARD1 expression and mchol accumulation, resulting in increased mitochondrial GSH levels, improved mitochondrial functional performance, decreased oxidative stress and protected NPC fibroblasts against oxidative stress-mediated cell death. Our results demonstrate a cholesterol-dependent inverse relationship between ACDase and STARD1 and provide a novel approach to target the accumulation of cholesterol in mitochondria in NPC disease

Malformations of the craniocervical junction (chiari type I and syringomyelia: classification, diagnosis and treatment)

Chiari disease (or malformation) is in general a congenital condition characterized by an anatomic defect of the base of the skull, in which the cerebellum and brain stem herniate through the foramen magnum into the cervical spinal canal. The onset of Chiari syndrome symptoms usually occurs in the second or third decade (age 25 to 45 years). Symptoms may vary between periods of exacerbation and remission. The diagnosis of Chiari type I malformation in patients with or without symptoms is established with neuroimaging techniques. The most effective therapy for patients with Chiari type I malformation/syringomyelia is surgical decompression of the foramen magnum, however there are non-surgical therapy to relieve neurophatic pain: either pharmacological and non-pharmacological. Pharmacological therapy use drugs that act on different components of pain. Non-pharmacological therapies are primarly based on spinal or peripheral electrical stimulation

Affinity for the Interface Underpins Potency of Antibodies Operating In Membrane Environments

The contribution of membrane interfacial interactions to recognition of membrane-embedded antigens by antibodies is currently unclear. This report demonstrates the optimization of this type of antibodies via chemical modification of regions near the membrane but not directly involved in the recognition of the epitope. Using the HIV-1 antibody 10E8 as a model, linear and polycyclic synthetic aromatic compounds are introduced at selected sites. Molecular dynamics simulations predict the favorable interactions of these synthetic compounds with the viral lipid membrane, where the epitope of the HIV-1 glycoprotein Env is located. Chemical modification of 10E8 with aromatic acetamides facilitates the productive and specific recognition of the native antigen, partially buried in the crowded environment of the viral membrane, resulting in a dramatic increase of its capacity to block viral infection. These observations support the harnessing of interfacial affinity through site-selective chemical modification to optimize the function of antibodies that target membrane-proximal epitopes.We are grateful to Professor Ueda (Kyushu University) for valuable advice. C.D. acknowledges RES (Red Espanola de Supercomputacio ' n) for providing computational resources. S.I. received a pre-doctoral fellowship from the Basque Government. P.C. acknowledges a research associate contract from the University of the Basque Country (DOCREC18/01) and a postdoctoral fellowship from the Basque Government (POS_2018_1_0066).This study was supported by the following grants: European Commission (790012 SI H2020MSCA-IF-2017 to E.R., J.-P.J., and J.L.N.); US NIAID (NIH) (R01 AI143563 to M.B.Z.); James B. Pendleton Charitable Trust (to M.B.Z.); Grant-in-Aid for Scientific Research on Innovative Areas "Chemistry for Multimolecular Crowding Biosystems, JSPS KAKENHI (JP17H06349 to A.O.); JSPS KAKENHI (15K06962 and 20H03228 to J.M.M.C.); Spanish MINECO (BIO2015-64421R and MINECO/AEI/FEDER, UE to J.L.N.); Spanish MCIU (RTI2018-095624B-C21 and MCIU/AEI/FEDER, UE to J.L.N.); and the Basque Government (IT1196-19) (to J.L.N.). C.E. acknowledges funding from Medical Research Council (MC_UU_12010/unit programs G0902418 and MC_UU_12025), Wolfson Foundation, Deutsche Forschungsgemeinschaft (Research unit 1905, Excellence Cluster Balance of the Microverse, Collaborative Research Centre 1278 Polytarget), Wellcome Institutional Strategic Support Fund, Oxford internal funds (EPA Cephalosporin Fund and John Fell Fund), and support from the Micron Oxford Advanced Bioimaging Unit (Wellcome Trust funding 107457/Z/15/Z). This research was undertaken, in part, thanks to funding from the CIFAR Azrieli Global Scholar program (to J.-P.J.) and the Canada Research Chairs program (950-231604 to J.-P.J.). This work was also supported by the Platform Project for Supporting Drug Discovery and Life Science Research (Basis for Supporting Innovative Drug Discovery and Life Science Research [BINDS] from AMED JP19am0101091)

A propósito de la hemofilia. ¡Tanto sufrimiento merece un final ético!

La hemofilia es una enfermedad hereditaria que afecta la coagulación. Esto puede ocasionar hemorragias espontáneas, después de una operación o de una lesión. Cada 17 de abril se conmemora el Día Mundial de la Hemofilia, elegido así por la Federación Mundial de Hemofilia en honor al día de nacimiento de su fundador, Frank Schnabel. Se trata de un día en el que se pretende conseguir sensibilizar y concientizar a la población mundial sobre la enfermedad y lograr compartir conocimientos e investigación para mejorar la calidad de vida de los pacientes con esta enfermedad

Aislamiento y caracterización de las células madre de la membrana amniótica: una nueva fuente para terapia celular e inmuno-modulación

Se realizó el aislamiento y caracterización de las células de 20 membranas amnióticas. De cada MA se obtuvo un promedio de 123±12x106 células epiteliales (hAEC) y 5.3x106 células mesenquimales (hAMSC). Las hEAC expresaron SSEA (1, 3 y 4), y TRA (1-60 y 1-81). Las hAMSC expresaron CD73, CD90, CD105 y no CD34, CD45, CD14 ni CD19. Ambas fueron negativas para HLA DR y positivas para transcriptos de Nanog, Oct-4 y Sox-2. En los cultivos primarios las hAEC mostraron menor capacidad de auto-renovación y proliferación que las hAMSC, y en los sub-cultivos desarrollaron Transición Epitelio-Mesénquima. Todas las hAEC mostraron potencialidad para diferenciarse en células de las tres capas germinales (neuroectodérmicas, hepatocíticas y cardiomiocíticas), algunas para diferenciación osteogénica y adipogénica, y ninguna para condrogénica. Todas las hAMSC se diferenciaron hacia líneas osteogénicas, adipogénicas y condrogénicas. En conclusión, la MA representa un reservorio de células madre pluripotenciales y multipotenciales inmunológicamente privilegiadas. In this study we determine the quantity and quality of amnion cells after isolation and culture from 20 placentas. Following our protocol, primary yields were 123 ±12 x 106 hAECs and 5.3x106 hAMSCs. Flow cytometric characterization showed expression of SSEA (1, 3 and 4) and TRA (1-60 and 1-81) in hAECs. hAMSC expressed CD73, CD90, CD105 and none CD45, CD34, CD14, CD19. Both cells types were negative for HLA-DR and exhibited Nanog, Oct-4 and Sox-2 transcripts. In primary cultures hAECs showed slower proliferation and less clonogenic capacity than hAMSCs, in sub-cultures they exhibited Epithelial Mesenchymal Transition. All hAECs samples were induced to differentiate into neuroectodermal, hepatic and cardiomiocitic cells, while osteogenic y adipogenic capacity varied between them. All hAMSCs samples exhibited osteogenic, adipogenic and chondrogenic differentiation capacity. In conclusion, term amnion may be a useful source of pluripotent and multipotent stem cells that possess a degree of immune privilege

Sphingomyelinases and Liver Diseases

Sphingolipids (SLs) are critical components of membrane bilayers that play a crucial role in their physico-chemical properties. Ceramide is the prototype and most studied SL due to its role as a second messenger in the regulation of multiple signaling pathways and cellular processes. Ceramide is a heterogeneous lipid entity determined by the length of the fatty acyl chain linked to its carbon backbone sphingosine, which can be generated either by de novo synthesis from serine and palmitoyl-CoA in the endoplasmic reticulum or via sphingomyelin (SM) hydrolysis by sphingomyelinases (SMases). Unlike de novo synthesis, SMase-induced SM hydrolysis represents a rapid and transient mechanism of ceramide generation in specific intracellular sites that accounts for the diverse biological effects of ceramide. Several SMases have been described at the molecular level, which exhibit different pH requirements for activity: neutral, acid or alkaline. Among the SMases, the neutral (NSMase) and acid (ASMase) are the best characterized for their contribution to signaling pathways and role in diverse pathologies, including liver diseases. As part of a Special Issue (Phospholipases: From Structure to Biological Function), the present invited review summarizes the physiological functions of NSMase and ASMase and their role in chronic and metabolic liver diseases, of which the most relevant is nonalcoholic steatohepatitis and its progression to hepatocellular carcinoma, due to the association with the obesity and type 2 diabetes epidemic. A better understanding of the regulation and role of SMases in liver pathology may offer the opportunity for novel treatments of liver diseasesWe acknowledge the support from grants SAF2017-85877R and PID2019-111669RB from Plan Nacional de I+D funded by the Agencia Estatal de Investigación (AEI) and the Fondo Europeo de Desarrollo Regional (FEDER) and from the CIBEREHD; the center grant P50AA011999 Southern California Research Center for ALPD and Cirrhosis funded by NIAAA/NIH; and support from AGAUR of the Generalitat de Catalunya SGR-2017-1112, European Cooperation in Science & Technology (COST) ACTION CA17112 Prospective European Drug-Induced Liver Injury Network, “ER stress-mitochondrial cholesterol axis in obesity-associated insulin resistance and comorbidities”—Ayudas FUNDACION BBVA and the Red Nacional 2018-102799-T de Enfermedades Metabólicas y Cáncer. Project 201916/31 Contribution of mitochondrial oxysterol and bile acid metabolism to liver carcinogenesis 2019 by Fundació Marato TV3.Peer reviewe

Hypoxia signaling and role in alcoholic liver disease

Resumen del trabajo presentado en el 2nd World Congress on Alcohol and Alcoholism Joint meeting of ISBRA and ESBRA, celebrado en Cracovia (Polonia), del 17 al 20 de septiembre de 2020Alcoholic liver disease (ALD) is a major cause of chronic liver disease and a main reason of liver related death. ALD represents a spectrum of liver alterations that begin with steatosis, which can progress to alcoholic steatohepatitis (ASH) and hepatocellular carcinoma (HCC). Unfortunately, the mechanisms underlying the progression from steatosis to advanced stages of ALD are still incompletely under-stood. Besides the abuse of alcohol consumption and genetic deter-minants, nutritional factors synergize with alcohol to promote ALD progression