Edición Génica para el Estudio de Canales Iónicos Vasculares y Proteínas Mitocondriales (VASCUMIT)https://uvadoc.uva.es/handle/10324/436772024-03-28T14:02:40Z2024-03-28T14:02:40ZKv1.3 channels modulate human vascular smooth muscle cells proliferation independently of mTOR signaling pathwayCidad Velasco, María del PilarMiguel-Velado, EduardoRuiz-McDavitt, ChristianAlonso Alonso, EsperanzaJiménez-Pérez, LauraAsuaje, AgustínCarmona, YamilaGarcía-Arribas, DanielLópez Díaz, JavierMarroquín, YngridFernández Gutiérrez, María MirellaRoqué, MercéPérez García, María TeresaLópez López, José Ramónhttps://uvadoc.uva.es/handle/10324/658812024-02-07T20:02:24Z2014-01-01T00:00:00ZPhenotypic modulation (PM) of vascular smooth muscle cells (VSMCs) is central to the process of intimal hyperplasia which constitutes a common pathological lesion in occlusive vascular diseases. Changes in the functional expression of Kv1.5 and Kv1.3 currents upon PM in mice VSMCs have been found to contribute to cell migration and proliferation. Using human VSMCs from vessels in which unwanted remodeling is a relevant clinical complication, we explored the contribution of the Kv1.5 to Kv1.3 switch to PM. Changes in the expression and the functional contribution of Kv1.3 and Kv1.5 channels were studied in contractile and proliferating VSMCs obtained from human donors. Both a Kv1.5 to Kv1.3 switch upon PM and an anti-proliferative effect of Kv1.3 blockers on PDGF-induced proliferation were observed in all vascular beds studied. When investigating the signaling pathways modulated by the blockade of Kv1.3 channels, we found that anti-proliferative effects of Kv1.3 blockers on human coronary artery VSMCs were occluded by selective inhibition of MEK/ERK and PLCγ signaling pathways, but were unaffected upon blockade of PI3K/mTOR pathway. The temporal course of the anti-proliferative effects of Kv1.3 blockers indicates that they have a role in the late signaling events essential for the mitogenic response to growth factors. These findings establish the involvement of Kv1.3 channels in the PM of human VSMCs. Moreover, as current therapies to prevent restenosis rely on mTOR blockers, our results provide the basis for the development of novel, more specific therapies.
2014-01-01T00:00:00ZmiR-126 contributes to the epigenetic signature of diabetic vascular smooth muscle and enhances antirestenosis effects of Kv1.3 blockersArévalo Martínez, MarycarmenCidad Velasco, María del PilarMoreno‐Estar, SaraFernández, MirellaAlbinsson, SebastianCózar Castellano, IreneLópez López, José RamónPérez García, María Teresahttps://uvadoc.uva.es/handle/10324/657662024-02-05T20:04:22Z2021-01-01T00:00:00ZObjectives: Restenosis after vessel angioplasty due to dedifferentiation of the vascular smooth muscle cells (VSMCs) limits the success of surgical treatment of vascular occlusions. Type 2 diabetes (T2DM) has a major impact on restenosis, with patients exhibiting more aggressive forms of vascular disease and poorer outcomes after surgery. Kv1.3 channels are critical players in VSMC proliferation. Kv1.3 blockers inhibit VSMCs MEK/ERK signalling and prevent vessel restenosis. We hypothesize that dysregulation of microRNAs (miR) play critical roles in adverse remodelling, contributing to Kv1.3 blockers efficacy in T2DM VSMCs.
Methods and results: We used clinically relevant in vivo models of vascular risk factors (VRF) and vessels and VSMCs from T2DM patients.
Resukts: Human T2DM vessels showed increased remodelling, and changes persisted in culture, with augmented VSMCs migration and proliferation. Moreover, there were downregulation of PI3K/AKT/mTOR and upregulation of MEK/ERK pathways, with increased miR-126 expression. The inhibitory effects of Kv1.3 blockers on remodelling were significantly enhanced in T2DM VSMCs and in VRF model. Finally, miR-126 overexpression confered "diabetic" phenotype to non-T2DM VSMCs by downregulating PI3K/AKT axis.
Conclusions: miR-126 plays crucial roles in T2DM VSMC metabolic memory through activation of MEK/ERK pathway, enhancing the efficacy of Kv1.3 blockers in the prevention of restenosis in T2DM patients.
2021-01-01T00:00:00ZmiR-126 contributes to the epigenetic signature of diabetic vascular smooth muscle and enhances antirestenosis effects of Kv1.3 blockersArévalo Martínez, MarycarmenCidad Velasco, María del PilarMoreno‐Estar, SaraFernández, MirellaAlbinsson, SebastianCózar Castellano, IreneLópez López, José RamónPérez García, María Teresahttps://uvadoc.uva.es/handle/10324/657152024-02-05T20:04:20Z2021-01-01T00:00:00ZLa reestenosis después de la angioplastia vascular debido a la desdiferenciación de las células musculares lisas vasculares (VSMC, por sus siglas en inglés) limita el éxito del tratamiento quirúrgico de las oclusiones vasculares. La diabetes tipo 2 (T2DM) tiene un gran impacto en la reestenosis, con pacientes que muestran formas más agresivas de enfermedad vascular y peores resultados después de la cirugía. Los canales Kv1.3 juegan un papel crítico en la proliferación de las VSMC. Los bloqueantes de Kv1.3 inhiben la señalización MEK/ERK de las VSMC y previenen la reestenosis vascular. En este trabajo se hipotetiza que la desregulación de los microARN (miR) juega un papel crítico en el remodelado adverso, contribuyendo a la eficacia de los bloqueantes de Kv1.3 en las VSMC con T2DM. Metodológicamente utilizamos modelos in vivo clínicamente relevantes con factores de riesgo vascular (FRV) y vasos y VSMC de pacientes con T2DM. En este trabajo se muestra que los vasos humanos con T2DM tienen un remodelado aumentado, y que los cambios persisten en cultivo, con la migración y la proliferación de las VSMC aumentadas. Además, se produce una regulación a la baja de las vías PI3K/AKT/mTOR y una regulación al alza de las vías MEK/ERK, con aumento de la expresión de miR-126. Los efectos inhibitorios de los bloqueantes de Kv1.3 en el remodelado son significativamente mayores en las VSMC de pacientes con T2DM y en el modelo FRV. Finalmente, la sobreexpresión de miR-126 confiere un fenotipo "diabético" a las VSMC no-T2DM al regular a la baja el eje PI3K/AKT. Por tanto se concluye que el miR-126 desempeña un papel crucial en el desarrollo de la memoria metabólica de las VSMC con T2DM a través de la activación de la vía MEK/ERK, mejorando la eficacia de los bloqueadores de Kv1.3 en la prevención de la reestenosis en pacientes con T2DM.
2021-01-01T00:00:00ZKv channels and vascular smooth muscle cell proliferationLópez López, José RamónCidad Velasco, María del PilarPérez García, María Teresahttps://uvadoc.uva.es/handle/10324/653792024-01-30T20:03:35Z2018-01-01T00:00:00ZKv channels are present in virtually all VSMCs and strongly influence contractile responses. However, they are also instrumental in the proliferative, migratory, and secretory functions of synthetic, dedifferentiated VSMCs upon PM. In fact, Kv channels not only contribute to all these processes but also are active players in the phenotypic switch itself. This review is focused on the role(s) of Kv channels in VSMC proliferation, which is one of the best characterized functions of dedifferentiated VSMCs. VSMC proliferation is a complex process requiring specific Kv channels at specific time and locations. Their identification is further complicated by their large diversity and the differences in expression across vascular beds. Of interest, both conserved changes in some Kv channels and vascular bed-specific regulation of others seem to coexist and participate in VSMC proliferation through complementary mechanisms. Such a system will add flexibility to the process while providing the required robustness to preserve this fundamental cellular response.
2018-01-01T00:00:00ZKv1.3 Channel Inhibition Limits Uremia-Induced Calcification in Mouse and Human Vascular Smooth MuscleCazaña Pérez, VioletaCidad Velasco, María del PilarNavarro-González, Juan F.Rojo Mencía, JorgeJaisser, FredericLópez López, José RamónÁlvarez de la Rosa, DiegoGiraldez, TeresaPérez García, María Teresahttps://uvadoc.uva.es/handle/10324/653782024-01-30T20:03:34Z2021-01-01T00:00:00ZChronic kidney disease (CKD) significantly increases cardiovascular risk. In advanced CKD stages, accumulation of toxic circulating metabolites and mineral metabolism alterations triggers vascular calcification, characterized by vascular smooth muscle cell (VSMC) transdifferentiation and loss of the contractile phenotype. Phenotypic modulation of VSMC occurs with significant changes in gene expression. Even though ion channels are an integral component of VSMC function, the effects of uremia on ion channel remodeling has not been explored. We used an in vitro model of uremia-induced calcification of human aorta smooth muscle cells (HASMCs) to study the expression of 92 ion channel subunit genes. Uremic serum-induced extensive remodeling of ion channel expression consistent with loss of excitability but different from the one previously associated with transition from contractile to proliferative phenotypes. Among the ion channels tested, we found increased abundance and activity of voltage-dependent K+ channel Kv1.3. Enhanced Kv1.3 expression was also detected in aorta from a mouse model of CKD. Pharmacological inhibition or genetic ablation of Kv1.3 decreased the amount of calcium phosphate deposition induced by uremia, supporting an important role for this channel on uremia-induced VSMC calcification.
2021-01-01T00:00:00ZActivation of the cation channel TRPM3 in perivascular nerves induces vasodilation of resistance arteriesAlonso Carbajo, LucíaAlpizar, Yeranddy A.Startek, Justyna B.López López, José RamónPérez García, María TeresaTalavera, Karelhttps://uvadoc.uva.es/handle/10324/653732024-01-30T20:03:31Z2019-01-01T00:00:00ZThe Transient Receptor Potential Melastatin 3 (TRPM3) is a Ca2+-permeable non-selective cation channel activated by the neurosteroid pregnenolone sulfate (PS). This compound was previously shown to contract mouse aorta by activating TRPM3 in vascular smooth muscle cells (VSMC), and proposed as therapeutic modulator of vascular functions. However, PS effects and the role of TRPM3 in resistance arteries remain unknown. Thus, we aimed at determining the localization and physiological role of TRPM3 in mouse mesenteric arteries. Real-time qPCR experiments, anatomical localization using immunofluorescence microscopy and patch-clamp recordings in isolated VSMC showed that TRPM3 expression in mesenteric arteries is restricted to perivascular nerves. Pressure myography experiments in wild type (WT) mouse arteries showed that PS vasodilates with a concentration-dependence that was best fit by two Hill components (effective concentrations, EC50, of 14 and 100 μM). The low EC50 component was absent in preparations from Trpm3 knockout (KO) mice and in WT arteries in the presence of the CGRP receptor antagonist BIBN 4096. TRPM3-dependent vasodilation was partially inhibited by a cocktail of K+ channel blockers, and not mediated by β-adrenergic signaling. We conclude that, contrary to what was found in aorta, PS dilates mesenteric arteries, partly via an activation of TRPM3 that triggers CGRP release from perivascular nerve endings and a subsequent activation of K+ channels in VSMC. We propose that TRPM3 is implicated in the regulation of the tone of resistance arteries and that its activation by yet unidentified endogenous damage-associated molecules lead to protective vasodilation responses in mesenteric arteries.
2019-01-01T00:00:00ZKv1.3 blockade inhibits proliferation of vascular smooth muscle cells in vitro and intimal hyperplasia in vivoBobi, JoaquimGarabito, ManelSolanes, NuriaCidad Velasco, María del PilarRamos-Pérez, VíctorPonce, AlbertoRigol, MontserratFreixa, XavierPérez-Martínez, ClaudiaPérez de Prado, ArmandoFernández-Vázquez, FelipeSabaté, ManelBorrós, SalvadorLópez López, José RamónPérez García, María TeresaRoqué, Mercéhttps://uvadoc.uva.es/handle/10324/653692024-01-30T20:03:29Z2020-01-01T00:00:00ZThe modulation of voltage-gated K+ (Kv) channels, involved in cell proliferation, arises as a potential therapeutic approach for the prevention of intimal hyperplasia present in in-stent restenosis (ISR) and allograft vasculopathy (AV). We studied the effect of PAP-1, a selective blocker of Kv1.3 channels, on development of intimal hyperplasia in vitro and in vivo in 2 porcine models of vascular injury. In vitro phenotypic modulation of VSMCs was associated to an increased functional expression of Kv1.3 channels, and only selective Kv1.3 channel blockers were able to inhibit porcine VSMC proliferation. The therapeutic potential of PAP-1 was then evaluated in vivo in swine models of ISR and AV. At 15-days follow-up, morphometric analysis demonstrated a substantial reduction of luminal stenosis in the allografts treated with PAP-1 (autograft 2.72 ± 1.79 vs allograft 10.32 ± 1.92 vs allograft + polymer 13.54 ± 8.59 vs allograft + polymer + PAP-1 3.06 ± 1.08 % of luminal stenosis; P = 0.006) in the swine model of femoral artery transplant. In the pig model of coronary ISR, using a prototype of PAP-1-eluting stent, no differences were observed regarding % of stenosis compared to control stents (31 ± 13 % vs 37 ± 18%, respectively; P = 0.372) at 28-days follow-up. PAP-1 treatment was safe and did not impair vascular healing in terms of delayed endothelialization, inflammation or thrombosis. However, an incomplete release of PAP-1 from stents was documented. We conclude that the use of selective Kv1.3 blockers represents a promising therapeutic approach for the prevention of intimal hyperplasia in AV, although further studies to improve their delivery method are needed to elucidate its potential in ISR.
2020-01-01T00:00:00ZElastin-like recombinamer-based devices releasing Kv1.3 blockers for the prevention of intimal hyperplasia: An in vitro and in vivo studyMoreno‐Estar, SaraSerrano, SofíaArévalo Martínez, MarycarmenCidad Velasco, María del PilarLópez López, José RamónSantos García, María MercedesPérez García, María TeresaArias Vallejo, Francisco Javierhttps://uvadoc.uva.es/handle/10324/653572024-01-30T20:03:27Z2020-01-01T00:00:00ZCoronary artery disease (CAD) is the most common cardiovascular disorder. Vascular surgery strategies for coronary revascularization (either percutaneous or open) show a high rate of failure because of restenosis of the vessel, due to phenotypic switch of vascular smooth muscle cells (VSMCs) leading to proliferation and migration. We have previously reported that the inhibition of Kv1.3 channel function with selective blockers represents an effective strategy for the prevention of restenosis in human vessels used for coronary angioplasty procedures. However, delivery systems for controlled release of these drugs have not been investigated. Here we tested the efficacy of several formulations of elastin like recombinamers (ELRs) hydrogels to deliver the Kv1.3 blocker PAP-1 in various restenosis models. The dose and time course of PAP-1 release from ELRs click hydrogels was able to inhibit human VSMC proliferation in vitro as well as remodeling of human vessels in organ culture and restenosis in in vivo models. We conclude that this combination of active compound and advanced delivery method could improve the outcomes of vascular surgery in patients. STATEMENT OF SIGNIFICANCE: Vascular surgery strategies for coronary revascularization show a high rate of failure, because of occlusion (restenosis) of the vessel, due to vascular smooth muscle cells proliferation and migration. We have previously reported that blockers of Kv1.3 channels represent an effective anti-restenosis therapy, but delivery systems for their controlled release have not being explored. Here we tested the efficacy of several formulations of elastin like recombinamers (ELRs) hydrogels to deliver the Kv1.3 blocker PAP-1 in various restenosis models, both in vivo and in vitro, and also in human vessels. We demonstrated that combination of active compound and advanced delivery method could improve the outcomes of vascular surgery in patients.
2020-01-01T00:00:00ZVoltage‐dependent conformational changes of Kv1.3 channels activate cell proliferationCidad Velasco, María del PilarAlonso Alonso, EsperanzaArévalo Martínez, MarycarmenCalvo, Enriquede la Fuente, Miguel A.Pérez García, María TeresaLópez López, José Ramónhttps://uvadoc.uva.es/handle/10324/653482024-01-30T20:03:26Z2020-01-01T00:00:00ZThe voltage-dependent potassium channel Kv1.3 has been implicated in proliferation in many cell types, based on the observation that Kv1.3 blockers inhibited proliferation. By modulating membrane potential, cell volume, and/or Ca2+ influx, K+ channels can influence cell cycle progression. Also, noncanonical channel functions could contribute to modulate cell proliferation independent of K+ efflux. The specificity of the requirement of Kv1.3 channels for proliferation suggests the involvement of molecule-specific interactions, but the underlying mechanisms are poorly identified. Heterologous expression of Kv1.3 channels in HEK cells has been shown to increase proliferation independently of K+ fluxes. Likewise, some of the molecular determinants of Kv1.3-induced proliferation have been located in the C-terminus region, where individual point mutations of putative phosphorylation sites (Y447A and S459A) abolished Kv1.3-induced proliferation. Here, we investigated the mechanisms linking Kv1.3 channels to proliferation exploring the correlation between Kv1.3 voltage-dependent molecular dynamics and cell cycle progression. Using transfected HEK cells, we analyzed both the effect of changes in resting membrane potential on Kv1.3-induced proliferation and the effect of mutated Kv1.3 channels with altered voltage dependence of gating. We conclude that voltage-dependent transitions of Kv1.3 channels enable the activation of proliferative pathways. We also found that Kv1.3 associated with IQGAP3, a scaffold protein involved in proliferation, and that membrane depolarization facilitates their interaction. The functional contribution of Kv1.3-IQGAP3 interplay to cell proliferation was demonstrated both in HEK cells and in vascular smooth muscle cells. Our data indicate that voltage-dependent conformational changes of Kv1.3 are an essential element in Kv1.3-induced proliferation.
2020-01-01T00:00:00ZThe secret life of ion channels: Kv1.3 potassium channels and proliferationPérez García, María TeresaCidad Velasco, María del PilarLópez López, José Ramónhttps://uvadoc.uva.es/handle/10324/653402024-01-30T20:03:25Z2018-01-01T00:00:00ZKv1.3 channels are involved in the switch to proliferation of normally quiescent cells, being implicated in the control of cell cycle in many different cell types and in many different ways. They modulate membrane potential controlling K + fluxes, sense changes in potential, and interact with many signaling molecules through their intracellular domains. From a mechanistic point of view, we can describe the role of Kv1.3 channels in proliferation with at least three different models. In the “membrane potential model,” membrane hyperpolarization resulting from Kv1.3 activation provides the driving force for Ca 2+ influx required to activate Ca 2+ -dependent transcription. This model explains most of the data obtained from several cells from the immune system. In the “voltage sensor model,” Kv1.3 channels serve mainly as sensors that transduce electrical signals into biochemical cascades, independently of their effect on membrane potential. Kv1.3-dependent proliferation of vascular smooth muscle cells (VSMCs) could fit this model. Finally, in the “channelosome balance model,” the master switch determining proliferation may be related to the control of the Kv1.3 to Kv1.5 ratio, as described in glial cells and also in VSMCs. Since the three mechanisms cannot function independently, these models are obviously not exclusive. Nevertheless, they could be exploited differentially in different cells and tissues. This large functional flexibility of Kv1.3 channels surely gives a new perspective on their functions beyond their elementary role as ion channels, although a conclusive picture of the mechanisms involved in Kv1.3 signaling to proliferation is yet to be reached.
2018-01-01T00:00:00ZVascular smooth muscle ion channels in essential hypertensionDaghbouche-Rubio, NuriaLópez López, José RamónPérez García, María TeresaCidad Velasco, María del Pilarhttps://uvadoc.uva.es/handle/10324/653272024-01-30T20:03:23Z2022-01-01T00:00:00ZHypertension is a highly prevalent chronic disease and the major risk factor for cardiovascular diseases, the leading cause of death worldwide. Hypertension is characterized by an increased vascular tone determined by the contractile state of vascular smooth muscle cells that depends on intracellular calcium levels. The interplay of ion channels determine VSMCs membrane potential and thus intracellular calcium that controls the degree of contraction, vascular tone and blood pressure. Changes in ion channels expression and function have been linked to hypertension, but the mechanisms and molecular entities involved are not completely clear. Furthermore, the literature shows discrepancies regarding the contribution of different ion channels to hypertension probably due to differences both in the vascular preparation and in the model of hypertension employed. Animal models are essential to study this multifactorial disease but it is also critical to know their characteristics to interpret properly the results obtained. In this review we summarize previous studies, using the hypertensive mouse (BPH) and its normotensive control (BPN), focused on the identified changes in the expression and function of different families of ion channels. We will focus on L-type voltage-dependent Ca2+ channels (Cav1.2), canonical transient receptor potential channels and four different classes of K+ channels: voltage-activated (Kv), large conductance Ca2+-activated (BK), inward rectifiers (Kir) and ATP-sensitive (KATP) K+ channels. We will describe the role of these channels in hypertension and we will discuss the importance of integrating individual changes in a global context to understand the complex interplay of ion channels in hypertension.
2022-01-01T00:00:00ZDevelopment of a novel in vitro model to study the modulatory role of the respiratory complex I in macrophage effector functionsSerrano-Lorenzo, PabloGobelli, DinoGarrido-Moraga, RocíoEsteban-Amo, María J.Orduña, Antoniode la Fuente, Miguel A.Martín, Miguel A.López López, José RamónSimarro Grande, Maríahttps://uvadoc.uva.es/handle/10324/653042024-01-30T20:03:19Z2023-01-01T00:00:00ZIncreasing evidence demonstrate that the electron transfer chain plays a critical role in controlling the effector functions of macrophages. In this work, we have generated a Ndufs4−/− murine macrophage cell lines. The Ndufs4 gene, which encodes a supernumerary subunit of complex I, is a mutational hotspot in Leigh syndrome patients. Ndufs4−/− macrophages showed decreased complex I activity, altered complex I assembly, and lower levels of maximal respiration and ATP production. These mitochondrial respiration alterations were associated with a shift towards a pro-inflammatory cytokine profile after lipopolysaccharide challenge and improved ability to phagocytose Gram-negative bacteria.
2023-01-01T00:00:00ZB cell–intrinsic deficiency of the Wiskott-Aldrich syndrome protein (WASp) causes severe abnormalities of the peripheral B-cell compartment in miceRecher, MikeBurns, Siobhan O.Fuente García, Miguel Ángel de laVolpi, StephanoDahlberg, CarinWalter, Jolan E.Moffitt, KristinMathew, DivijHonke, NadineLang, Philipp A.Patrizi, LauraFalet, HervéKeszei, MartonMizui, MasayukiCsizmadia, EvaCandotti, FabioNadeau, KariBouma, GerbenDelmonte, Ottavia M.Frugoni, FrancescoFerraz Fomini, Angela B.Buchbinder, DavidLundequist, Emma MariaMassaad, Michel J.Tsokos, George C.Hartwig, John H.Manis, JohnTerhorst, CoxGeha, Raif S.Snapper, Scott B.Lang, Karl S.Malley, RichardWesterberg, Lisa S.Thrasher, Adrian J.Notarangelo, Luigi D.https://uvadoc.uva.es/handle/10324/446362021-06-24T07:17:57Z2012-01-01T00:00:00ZWiskott Aldrich syndrome (WAS) is caused by mutations in the WAS gene that encodes for a protein (WASp) involved in cytoskeleton organization in hematopoietic cells. Several distinctive abnormalities of T, B, and natural killer lymphocytes; dendritic cells; and phagocytes have been found in WASp-deficient patients and mice; however, the in vivo consequence of WASp deficiency within individual blood cell lineages has not been definitively evaluated. By conditional gene deletion we have generated mice with selective deficiency of WASp in the B-cell lineage (B/WcKO mice). We show that this is sufficient to cause a severe reduction of marginal zone B cells and inability to respond to type II T-independent Ags, thereby recapitulating phenotypic features of complete WASp deficiency. In addition, B/WcKO mice showed prominent signs of B-cell dysregulation, as indicated by an increase in serum IgM levels, expansion of germinal center B cells and plasma cells, and elevated autoantibody production. These findings are accompanied by hyperproliferation of WASp-deficient follicular and germinal center B cells in heterozygous B/WcKO mice in vivo and excessive differentiation of WASp-deficient B cells into class-switched plasmablasts in vitro, suggesting that WASp-dependent B cell–intrinsic mechanisms critically contribute to WAS-associated autoimmunity.
2012-01-01T00:00:00ZNAD+ regulates Treg cell fate and promotes allograft survival via a systemic IL-10 production that is CD4+ CD25+ Foxp3+ T cells independentElkhal, AbdallahRodriguez-Cetina Biefer, HéctorHeinbokel, TimmUehara, HirofumiQuante, MarkusSeyda, MidasSchuitenmaker, Jeroen M.Krenzien, FelixCamacho, VirginiaFuente García, Miguel Ángel de laGhiran, IonitaTullius, Stefan G.https://uvadoc.uva.es/handle/10324/446332021-06-24T07:17:55Z2016-01-01T00:00:00ZCD4+ CD25+ Foxp3+ Tregs have been shown to play a central role in immune homeostasis while
preventing from fatal inflammatory responses, while Th17 cells have traditionally been recognized
as pro-inflammatory mediators implicated in a myriad of diseases. Studies have shown the potential
of Tregs to convert into Th17 cells, and Th17 cells into Tregs. Increasing evidence have pointed out
CD25 as a key molecule during this transdifferentiation process, however molecules that allow such
development remain unknown. Here, we investigated the impact of NAD+ on the fate of CD4+ CD25+
Foxp3+ Tregs in-depth, dissected their transcriptional signature profile and explored mechanisms
underlying their conversion into IL-17A producing cells. Our results demonstrate that NAD+ promotes
Treg conversion into Th17 cells in vitro and in vivo via CD25 cell surface marker. Despite the reduced
number of Tregs, known to promote homeostasis, and an increased number of pro-inflammatory
Th17 cells, NAD+ was able to promote an impressive allograft survival through a robust systemic
IL-10 production that was CD4+ CD25+ Foxp3+ independent. Collectively, our study unravels a novel
immunoregulatory mechanism of NAD+ that regulates Tregs fate while promoting allograft survival
that may have clinical applications in alloimmunity and in a wide spectrum of inflammatory conditions.
2016-01-01T00:00:00ZRole of FAST kinase domains 3 (FASTKD3) in post-transcriptional regulation of mitochondrial gene expressionBoehm, ErikZornoza, MaríaJourdain, Alexis A.Delmiro Magdalena, AitorGarcía Consuegra, InésTorres Merino, RebecaOrduña Domingo, AntonioMartín Ferrero, Miguel ÁngelMartinou, Jean-ClaudeFuente García, Miguel Ángel de laSimarro Grande, Maríahttps://uvadoc.uva.es/handle/10324/446262021-06-24T07:17:53Z2016-01-01T00:00:00ZThe Fas-activated serine/threonine kinase (FASTK) family of proteins has recently emerged as a central regulator of mitochondrial gene expression through the function of an unusual RNA-binding domain named RAP (for RNA-binding domain abundant in Apicomplexans), shared by all six members of the family. Here we describe the role of one of the less characterized members, FASTKD3, in mitochondrial RNA metabolism. First, we show that, in contrast to FASTK, FASTKD2, and FASTKD5, FASTKD3 does not localize in mitochondrial RNA granules, which are sites of processing and maturation of mtRNAs and ribosome biogenesis. Second, we generated FASTKD3 homozygous knock-out cell lines by homologous recombination and observed that the absence of FASTKD3 resulted in increased steady-state levels and half-lives of a subset of mature mitochondrial mRNAs: ND2, ND3, CYTB, COX2, and ATP8/6. No aberrant processing of RNA precursors was observed. Rescue experiments demonstrated that RAP domain is required for FASTKD3 function in mRNA stability. Besides, we describe that FASTKD3 is required for efficient COX1 mRNA translation without altering mRNA levels, which results in a decrease in the steady-state levels of COX1 protein. This finding is associated with reduced mitochondrial complex IV assembly and activity. Our observations suggest that the function of this family of proteins goes beyond RNA processing and ribosome assembly and includes RNA stability and translation regulation within mitochondria.
2016-01-01T00:00:00ZThe FASTK family of proteins : emerging regulators of mitochondrial RNA biologyJourdain, Alexis A.Popow, JohannesFuente García, Miguel Ángel de laMartinou, Jean-ClaudeAnderson, PaulSimarro Grande, Maríahttps://uvadoc.uva.es/handle/10324/446242021-06-24T07:17:51Z2017-01-01T00:00:00ZThe FASTK family proteins have recently emerged as key post-transcriptional regulators of mitochondrial gene expression. FASTK, the founding member and its homologs FASTKD1–5 are architecturally related RNA-binding proteins, each having a different function in the regulation of mitochondrial RNA biology, from mRNA processing and maturation to ribosome assembly and translation. In this review, we outline the structure, evolution and function of these FASTK proteins and discuss the individual role that each has in mitochondrial RNA biology. In addition, we highlight the aspects of FASTK research that still require more attention.
2017-01-01T00:00:00Z