Inhibidores de la vía PI3K/Akt/mTOR: utilidad en la profilaxis/tratamiento de la enfermedad injerto contra huésped

[ES] La enfermedad injerto contra huésped (EICH) constituye la principal causa de morbi-mortalidad en los pacientes sometidos a un trasplante alogénico de progenitores hematopoyéticos (aloTPH). Los linfocitos T del donante, que se activan frente a las células del receptor, son los principales efectores celulares implicados en el desarrollo de la EICH. Una de las rutas de señalización claves en la activación de las células T es la ruta PI3K/Akt/mTOR. Por ello, el uso de fármacos que bloqueen dicha ruta podría resultar eficaz para inhibir el desarrollo de la enfermedad. En los últimos años, la administración del inhibidor de mTOR rapamicina (Sirolimus) ha proporcionado resultados prometedores en la profilaxis de la EICH. Aún así, la incidencia de la enfermedad continúa siendo elevada. Nuestra hipótesis es que la limitada efectividad clínica de la rapamicina puede deberse a que ejerce un bloqueo incompleto de la ruta PI3K/Akt/mTOR pues inhibe la actividad de mTOR cuando forma parte del complejo mTORC1 pero tiene escasa eficacia en la inhibición del complejo mTORC2. Por tanto, fármacos que bloqueen la vía de manera más efectiva podrían inhibir más eficazmente la activación de los linfocitos T alorreactivos y, por tanto, el desarrollo de la EICH. Por ello analizamos el efecto de un inhibidor dual de mTORC1/mTORC2 y de un inhibidor dual de PI3K/mTOR (mTORC1 y mTORC2) sobre células T y evaluamos su potencial utilidad en la profilaxis de la EICH. A su vez, contrastamos la actividad de ambos compuestos con la de inhibidores específicos de mTORC1 (rapamicina) y PI3K (BKM120). Los estudios in vitro con células T humanas demostraron que ambos inhibidores duales bloquean de manera más eficaz que rapamicina y BKM120 la activación de proteínas de la ruta PI3K/Akt/mTOR, así como la proliferación y la producción de marcadores de activación linfocitaria. Además, los inhibidores duales previenen, de manera más efectiva que rapamicina y BKM120, la activación de las células T naïve y generan tolerancia frente a células alogénicas, manteniendo una respuesta eficaz frente a patógenos como citomegalovirus. Finalmente, comprobamos en un modelo murino de EICH que la administración de los inhibidores duales disminuye el daño tisular ocasionado por la enfermedad y mejora significativamente la supervivencia con respecto a los ratones no tratados aunque no se alcanza la tasa de supervivencia lograda con rapamicina. Es probable que, a las concentraciones utilizadas, los fármacos induzcan cierta toxicidad. Por ello, futuros estudios permitirán determinar si la optimización de las dosis y el calendario de administración permiten reducir la toxicidad y aumentar la supervivencia. En definitiva, estos resultados confirman el efecto inmunosupresor de los inhibidores duales de mTORC1/mTORC2 y PI3K/mTOR sobre linfocitos T y avalan su posible utilidad en la profilaxis de la EICH

TDR pressure cell for monitoring water content retention and bulk electrical conductivity curves in undisturbed soil samples

30 Pags., 4 Tabls., 5 Figs.-- The .pdf file is the last author version.-- The definitive version is avalaible at: http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1099-1085The water retention curve (θ(ψ)), which defines the relationship between soil volumetric water content (θ) and matric potential (ψ), is of paramount importance in characterizing the hydraulic behaviour of soils. However, few methods are so far available for estimating θ(ψ) in undisturbed soil samples. We present a new design of TDR-pressure cell (TDR-Cell) for estimating θ(ψ) in undisturbed soil samples. The TDR-Cell consists of a 50-mm-long and 50-mm internal diameter stainless steel cylinder (which constitutes the outer frame of a coaxial line) attached to a porous ceramic disc and closed at the ends with two aluminium lids. A 49-mm-long and 3-mm-diameter stainless steel rod, which runs longitudinally through the centre of the cylinder, constitutes the inner rod of a coaxial TDR probe. The TDR-Cell was used to determine the θ(ψ) curves of a packed sand and seven undisturbed soil samples from three profiles of agricultural soils. These θ(ψ) curves were subsequently compared to those obtained from the corresponding 2-mm sieved soils using the pressure plate method. Measurements of bulk electrical conductivity, σa, as a function of the water content, σa(θ), of the undisturbed soil samples were also performed. An excellent correlation (R2 = 0·988) was found between the θ values measured by TDR on the different undisturbed soils and the corresponding θ obtained from the soil gravimetric water content. A typical bimodal θ(ψ) function was found for most of the undisturbed soil samples. Comparison between the θ(ψ) curves measured with the TDR-Cell and those obtained from the 2-mm sieved soils showed that the pressure plate method overestimates θ at low ψ values. The σa(θ) relationship was well described by a simple power expression (R2 > 0·95), in which the power factor, defined as tortuosity, ranged between 1·18 and 3·75.This research was supported by the Ministerio de Ciencia e Inovación (Grants: AGL2007-66320-CO2-02/AGR), CSIC (Grants: PIE-200840I214 and 2008401246) and DGA-Obra social La Caixa (Grants: GA-LC-010/2008; GA-LC-006-2008).Peer reviewe

Polymorphisms in receptors involved in opsonic and nonopsonic phagocytosis, and correlation with risk of infection in oncohematology patients

Producción CientíficaHigh-risk hematological malignancies are a privileged setting for infection by opportunistic microbes, with invasive mycosis being one of the most serious complications. Recently, genetic background has emerged as an unanticipated risk factor. For this reason, polymorphisms for genes encoding archetypal receptors involved in the opsonic and nonopsonic clearance of microbes, pentraxin-3 (PTX3) and Dectin-1, respectively, were studied and correlated with the risk of infection. Fungal, bacterial, and viral infections were registered for a group of 198 patients with highrisk hematological malignancies. Polymorphisms for the pentraxin-3 gene (PTX3) showed a significant association with the risk of fungal infection by Candida spp. and, especially, by Aspergillus spp. This link remained even for patients undergoing antifungal prophylaxis, thus demonstrating the clinical relevance of PTX3 in the defense against fungi. CLEC7A polymorphisms did not show any definite correlation with the risk of invasive mycosis, nor did they influence the expression of Dectin-1 isoforms generated by alternative splicing. The PTX3 mRNA expression level was significantly lower in samples from healthy volunteers who showed these polymorphisms, although no differences were observed in the extents of induction elicited by bacterial lipopolysaccharide and heat-killed Candida albicans, thus suggesting that the expression of PTX3 at the start of infection may influence the clinical outcome. PTX3 mRNA expression can be a good biomarker to establish proper antifungal prophylaxis in immunodepressed patients

Relation among Aromatase P450 and Tumoral Growth in Human Prolactinomas

[EN]The pituitary gland is part of hypothalamic-pituitary–gonadal axis, which controls development, reproduction, and aging in humans and animals. In addition, the pituitary gland is regulated mainly by hormones and neurotransmitters released from the hypothalamus and by systemic hormones secreted by target glands. Aromatase P450, the enzyme responsible for the catabolization of aromatizable androgens to estrogens, is expressed in different parts of body, including the pituitary gland. Moreover, aromatase P450 is involved in sexual dimorphism where alteration in the level of aromatase can initiate a number of diseases in both genders. On the other hand, the direct actions of estrogens, mainly estradiol, are well known for stimulating prolactin release. Numerous studies have shown that changes in the levels of estrogens, among other factors, have been implicated in the genesis and development of prolactinoma. The pituitary gland can produce estradiol locally in several types of endocrine cells, and it is possible that aromatase could be responsible for the maintenance of the population of lactotroph cells and the modulation of the action of central or peripheral regulators. Aromatase overexpression due to inappropriate gene regulation has clinical effects such as the pathogenesis of prolactinomas. The present study reports on the synthesis of pituitary aromatase, its regulation by gonadal steroids, and the physiological roles of aromatase on pituitary endocrine cells. The involvement of aromatase in the pathogenesis of pituitary tumors, mainly prolactinomas, through the auto-paracrine production of estradiol is reviewed

Endoplasmic reticulum stress sensor IRE1α enhances IL-23 expression by human dendritic cells

Producción CientíficaHuman monocyte-derived dendritic cells (DCs) exposed to pathogen-associated molecular patterns (PAMPs) undergo bioenergetic changes that influence the immune response. We found that stimulation with PAMPs enhanced glycolysis in DCs, whereas oxidative phosphorylation remained unaltered. Glucose starvation and the hexokinase inhibitor 2-deoxy-d-glucose (2-DG) modulated cytokine expression in stimulated DCs. Strikingly, IL23A was markedly induced upon 2-DG treatment, but not during glucose deprivation. Since 2-DG can also rapidly inhibit protein N-glycosylation, we postulated that this compound could induce IL-23 in DCs via activation of the endoplasmic reticulum (ER) stress response. Indeed, stimulation of DCs with PAMPs in the presence of 2-DG robustly activated inositol-requiring protein 1α (IRE1α) signaling and to a lesser extent the PERK arm of the unfolded protein response. Additional ER stressors such as tunicamycin and thapsigargin also promoted IL-23 expression by PAMP-stimulated DCs. Pharmacological, biochemical, and genetic analyses using conditional knockout mice revealed that IL-23 induction in ER stressed DCs stimulated with PAMPs was IRE1α/X-box binding protein 1-dependent upon zymosan stimulation. Interestingly, we further evidenced PERK-mediated and CAAT/enhancer-binding protein β-dependent trans-activation of IL23A upon lipopolysaccharide treatment. Our findings uncover that the ER stress response can potently modulate cytokine expression in PAMP-stimulated human DCs.Plan Nacional de Salud y Farmacia (Proyecto SAF2013-44521-R

Tricarboxylic acid cycle activity and remodeling of glycerophosphocholine lipids support cytokine induction in response to fungal patterns

Producción CientíficaIncreased glycolysis parallels immune cell activation, but the role of pyruvate remains largely unexplored. We found that stimulation of dendritic cells with the fungal surrogate zymosan causes decreases of pyruvate, citrate, itaconate, and a-ketoglutarate, while increasing oxaloacetate, succinate, lactate, oxygen consumption, and pyruvate dehydrogenase activity. Expression of IL10 and IL23A (the gene encoding the p19 chain of IL-23) depended on pyruvate dehydrogenase activity. Mechanistically, pyruvate reinforced histone H3 acetylation, and acetate rescued the effect of mitochondrial pyruvate carrier inhibition, most likely because it is a substrate of the acetyl-CoA producing enzyme ACSS2. Mice lacking the receptor of the lipid mediator platelet-activating factor (PAF; 1-O-hexadecyl-2-acetyl-sn-glycero-3-phosphocholine) showed reduced production of IL-10 and IL-23 that is explained by the requirement of acetyl-CoA for PAF biosynthesis and its ensuing autocrine function. Acetyl-CoA therefore intertwines fatty acid remodeling of glycerophospholipids and energetic metabolism during cytokine induction.Plan Nacional de Salud y Farmacia (Proyectos SAF2013-44521-R, SAF2017-83079-R, BFU2014-53469-P, and BFU201)4- 53469-PJunta de Castilla y León - Fondo Social Europeo (Proyecto CSI035P17

Hif-1α knockdown reduces glycolytic metabolism and induces cell death of human synovial fibroblasts under normoxic conditions

[Abstract] Increased glycolysis and HIF-1α activity are characteristics of cells under hypoxic or inflammatory conditions. Besides, in normal O2 environments, elevated rates of glycolysis support critical cellular mechanisms such as cell survival. The purpose of this study was to analyze the contribution of HIF-1α to the energy metabolism and survival of human synovial fibroblasts (SF) under normoxic conditions. HIF-1α was silenced using lentiviral vectors or small-interfering RNA (siRNA) duplexes. Expression analysis by qRT-PCR and western blot of known HIF-1α target genes in hypoxia demonstrated the presence of functional HIF-1α in normoxic SF and confirmed the glycolytic enzyme glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a HIF-1α target even in normoxia. HIF-1α silencing induced apoptotic cell death in cultured SF and, similarly, treatment with glycolytic, but not with OXPHOS inhibitors, induced SF death. Finally, in vivo HIF-1α targeting by siRNA showed a significant reduction in the viability of human SF engrafted into a murine air pouch. Our results demonstrate that SF are highly dependent on glycolytic metabolism and that HIF-1α plays a regulatory role in glycolysis even under aerobic conditions. Local targeting of HIF-1α provides a feasible strategy to reduce SF hyperplasia in chronic arthritic diseases.Instituto de Salud Carlos III; FIS 12/439Instituto de Salud Carlos III; RETICS RD12/009Instituto de Salud Carlos III; CP13/00014Comunidad de Madrid; RAPHYME-CM S2010/BMD235

Effects of Covid-19 on the Online Library and Information Science Degree at the University of León (Spain)

.The Degree in Library Science and Documentation of the University of León started during the 1990–1991 academic year. This first curriculum suffered from a strong presence of subjects from the humanities, with a low fraction of experimental work in many subjects because of its inclusion within the Faculty of Philosophy and Letters. The first years attracted large numbers of students. However, the subsequent decrease in the number of students pursuing the degree drove us to initiate a change toward blended and online modalities. The Librarianship and Documentation Area of the University of León (ULe) already has a long history in blended teaching, starting with the Degree in Librarianship and Documentation, which has used the platform aul@unileon since the 2006–2007 academic year; the Degree of Information and Documentation has used the blended modality since the 2010–2011 academic year, and it has been offered in the distance learning modality since the 2014–2015 academic year. These new technologies have been fully introduced into university education and have facilitated the teaching–learning process through the use of interactive programs via the Internet. The main objective of this column is to determine and study the kind of multimedia tools used by professors of the Bachelor of Information and Documentation at the University of León during the teaching–learning process and in virtual teaching before the COVID-19 pandemic, as well as to report which new tools were introduced by the university for this reason. We study the student–teacher and student–student interactions to help promote communication and participatory learning through chats, forums, email, hangouts, Skype, Meet, videoconferences, etc. To carry out this study, two types of methodology were applied: satisfaction surveys implemented by the Quality Office of the ULe to determine the degree of satisfaction of students and teachers, and a study of annual reportsS

Analysis of incidence, risk factors and clinical outcome of thromboembolic and bleeding events in 431 allogeneic hematopoietic stem cell transplantation recipients

This is an open-access paper.-- et al.Allogeneic hematopoietic stem cell transplantation recipients have an increasing risk of both hemorrhagic and thrombotic complications. However, the competing risks of two of these life-threatening complications in these complex patients have still not been well defined. We retrospectively analyzed data from 431 allogeneic transplantation recipients to identify the incidence, risk factors and mortality due to thrombosis and bleeding. Significant clinical bleeding was more frequent than symptomatic thrombosis. The cumulative incidence of a bleeding episode was 30.2% at 14 years. The cumulative incidence of a venous or arterial thrombosis at 14 years was 11.8% and 4.1%, respectively. The analysis of competing factors for venous thrombosis revealed extensive chronic graft-versus-host disease to be the only independent prognostic risk factor. By contrast, six factors were associated with an increased risk of bleeding; advanced disease, ablative conditioning regimen, umbilical cord blood transplantation, anticoagulation, acute III-IV graft-versus-host disease, and transplant-associated microangiopathy. The development of thrombosis did not significantly affect overall survival (P=0.856). However, significant clinical bleeding was associated with inferior survival (P<0.001). In allogeneic hematopoietic stem cell transplantation, significant clinical bleeding is more common than thrombotic complications and affects survival.Peer Reviewe

Effect of mTORC1/mTORC2 inhibition on T cell function: potential role in graft-versus-host disease control

Producción CientíficaThe mechanistic target of rapamycin (mTOR) pathway is crucial for the activation and function of T cells, which play an essential role in the development of graft-versus-host disease (GvHD). Despite its partial ability to block mTOR pathway, the mTORC1 inhibitor rapamycin has shown encouraging results in the control of GvHD. Therefore, we considered that simultaneous targeting of both mTORC1 and mTORC2 complexes could exert a more potent inhibition of T cell activation and, thus, could have utility in GvHD control. To assess this assumption, we have used the dual mTORC1/mTORC2 inhibitors CC214-1 and CC214-2. In vitro studies confirmed the superior ability of CC214-1 versus rapamycin to block mTORC1 and mTORC2 activity and to reduce T cell proliferation. Both drugs induced a similar decrease in Th1/Th2 cytokine secretion, but CC214-1 was more efficient in inhibiting na€ıve T cell activation and the expression of Tcell activation markers. In addition, CC214-1 induced specific tolerance against alloantigens, while preserving anti-cytomegalovirus response. Finally, in a mouse model of GvHD, the administration of CC214-2 significantly improved mice survival and decreased GvHD-induced damages. In conclusion, the current study shows, for the first time, the immunosuppressive ability of CC214-1 on T lymphocytes and illustrates the role of CC214-2 in the allogeneic transplantation setting as a possible GvHD prophylaxis agent.Gerencia Regional de Salud de Castilla y León (Proyecto GRS 726/A13