DEP06 - Artículos de revistaDpto. Bioquímica y Biología Molecular y Fisiología - Artículos de revistahttps://uvadoc.uva.es/handle/10324/12132024-03-29T07:40:22Z2024-03-29T07:40:22ZThe biological action and structural characterization of eryngitin 3 and 4, ribotoxin-like proteins from Pleurotus eryngii fruiting bodiesRagucci, SaraLandi, NicolaCitores González, LucíaIglesias Álvarez, María del RosarioRusso, RositaClemente, AngelaSaviano, MichelePedone, Paolo VincenzoChambery, AngelaFerreras Rodríguez, José MiguelDi Maro, Antimohttps://uvadoc.uva.es/handle/10324/668602024-03-20T20:00:34Z2023-01-01T00:00:00ZRibotoxin-like proteins (RL-Ps) are specific ribonucleases found in mushrooms that are able to cleave a single phosphodiester bond located in the sarcin–ricin loop (SRL) of the large rRNA. The cleaved SRL interacts differently with some ribosomal proteins (P-stalk). This action blocks protein synthesis because the damaged ribosomes are unable to interact with elongation factors. Here, the amino acid sequences of eryngitin 3 and 4, RL-Ps isolated from Pleurotus eryngii fruiting bodies, were determined to (i) obtain structural information on this specific ribonuclease family from edible mushrooms and (ii) explore the structural determinants which justify their different biological and antipathogenic activities. Indeed, eryngitin 3 exhibited higher toxicity with respect to eryngitin 4 against tumoral cell lines and model fungi. Structurally, eryngitin 3 and 4 consist of 132 amino acids, most of them identical and exhibiting a single free cysteinyl residue. The amino acidic differences between the two toxins are (i) an additional phenylalanyl residue at the N-terminus of eryngitin 3, not retrieved in eryngitin 4, and (ii) an additional arginyl residue at the C-terminus of eryngitin 4, not retrieved in eryngitin 3. The 3D models of eryngitins show slight differences at the N- and C-terminal regions. In particular, the positive electrostatic surface at the C-terminal of eryngitin 4 is due to the additional arginyl residue not retrieved in eryngitin 3. This additional positive charge could interfere with the binding to the SRL (substrate) or with some ribosomal proteins (P-stalk structure) during substrate recognition.
2023-01-01T00:00:00ZCutaneous Wound Healing in Diabetic Mice Is Improved by Topical Mineralocorticoid Receptor BlockadeNguyen, Van TuanFarman, NicolettePalacios-Ramirez, RobertoSbeih, MariaBehar-Cohen, FrancineAractingi, SélimJaisser, Frederichttps://uvadoc.uva.es/handle/10324/662762024-02-15T20:00:53Z2020-01-01T00:00:00ZSkin ulcers resulting from impaired wound healing are a serious complication of diabetes. Unresolved inflammation, associated with the dysregulation of both the phenotype and function of macrophages, is involved in the poor healing of diabetic wounds. Here, we report that topical pharmacological inhibition of the mineralocorticoid receptor (MR) by canrenoate or MR small interfering RNA can resolve inflammation to improve delayed skin wound healing in diabetic mouse models; importantly, wounds from normal mice are unaffected. The beneficial effect of canrenoate is associated with an increased ratio of anti-inflammatory M2 macrophages to proinflammatory M1 macrophages in diabetic wounds. Furthermore, we show that MR blockade leads to downregulation of the MR target, LCN2, which may facilitate macrophage polarization toward the M2 phenotype and improve impaired angiogenesis in diabetic wounds. Indeed, diabetic LCN2-deficient mice showed improved wound healing associated with macrophage M2 polarization and angiogenesis. In addition, recombinant LCN2 protein prevented IL-4-induced macrophage switch from M1 to M2 phenotype. In conclusion, topical MR blockade accelerates skin wound healing in diabetic mice via LCN2 reduction, M2 macrophage polarization, prevention of inflammation, and induction of angiogenesis.
2020-01-01T00:00:00ZBiglycan Is a Novel Mineralocorticoid Receptor Target Involved in Aldosterone/Salt-Induced Glomerular InjuryNakamura, ToshifumiBonnard, BenjaminPalacios-Ramirez, RobertoFernández-Celis, AmayaJaisser, FrédéricLópez-Andrés, Nataliahttps://uvadoc.uva.es/handle/10324/662742024-02-15T20:00:50Z2022-06-15T00:00:00ZThe beneficial effects of mineralocorticoid receptor (MR) antagonists (MRAs) for various kidney diseases are established. However, the underlying mechanisms of kidney injury induced by MR activation remain to be elucidated. We recently reported aldosterone-induced enhancement of proteoglycan expression in mitral valve interstitial cells and its association with fibromyxomatous valvular disorder. As the expression of certain proteoglycans is elevated in several kidney diseases, we hypothesized that proteoglycans mediate kidney injury in the context of aldosterone/MR pathway activation. We evaluated the proteoglycan expression and tissue injury in the kidney and isolated glomeruli of uninephrectomy/aldosterone/salt (NAS) mice. The MRA eplerenone was administered to assess the role of the MR pathway. We investigated the direct effects of biglycan, one of the proteoglycans, on macrophages using isolated macrophages. The kidney samples from NAS-treated mice showed enhanced fibrosis and increased expression of biglycan accompanying glomerular macrophage infiltration and enhanced expression of TNF-α, iNOS, Nox2, CCL3 (C-C motif chemokine ligand 3), and phosphorylated NF-κB. Eplerenone blunted these changes. Purified biglycan stimulated macrophages to express TNF-α, iNOS, Nox2, and CCL3. This was prevented by a toll-like receptor 4 (TLR4) or NF-κB inhibitor, indicating that biglycan stimulation is dependent on the TLR4/NF-κB pathway. We identified the proteoglycan biglycan as a novel target of MR involved in MR-induced glomerular injury and macrophage infiltration via a biglycan/TLR4/NF-κB/CCL3 cascade
2022-06-15T00:00:00ZInvolvement of Bcl-2 Family Proteins in Tetraploidization-Related SenescenceBarriuso, DanielAlvarez-Frutos, LuciaGonzalez-Gutierrez, LuciaMotiño, OmarKroemer, GuidoPalacios-Ramirez, RobertoSenovilla, Laurahttps://uvadoc.uva.es/handle/10324/662722024-02-15T20:00:47Z2023-03-28T00:00:00ZThe B-cell lymphoma 2 (Bcl-2) family of proteins is the main regulator of apoptosis. However, multiple emerging evidence has revealed that Bcl-2 family proteins are also involved in cellular senescence. On the one hand, the different expression of these proteins determines the entry into senescence. On the other hand, entry into senescence modulates the expression of these proteins, generally conferring resistance to apoptosis. With some exceptions, senescent cells are characterized by the upregulation of antiapoptotic proteins and downregulation of proapoptotic proteins. Under physiological conditions, freshly formed tetraploid cells die by apoptosis due to the tetraploidy checkpoint. However, suppression of Bcl-2 associated x protein (Bax), as well as overexpression of Bcl-2, favors the appearance and survival of tetraploid cells. Furthermore, it is noteworthy that our laboratory has shown that the joint absence of Bax and Bcl-2 antagonist/killer (Bak) favors the entry into senescence of tetraploid cells. Certain microtubule inhibitory chemotherapies, such as taxanes and vinca alkaloids, induce the generation of tetraploid cells. Moreover, the combined use of inhibitors of antiapoptotic proteins of the Bcl-2 family with microtubule inhibitors increases their efficacy. In this review, we aim to shed light on the involvement of the Bcl-2 family of proteins in the senescence program activated after tetraploidization and the possibility of using this knowledge to create a new therapeutic strategy targeting cancer cells.
2023-03-28T00:00:00ZMultiomics insights on the onset, progression, and metastatic evolution of breast cancerAlvarez-Frutos, LuciaBarriuso, DanielDuran, MercedesInfante, MarKroemer, GuidoPalacios-Ramirez, RobertoSenovilla, Laurahttps://uvadoc.uva.es/handle/10324/662702024-02-15T20:00:41Z2023-12-19T00:00:00ZBreast cancer is the most common malignant neoplasm in women. Despite progress to date, 700,000 women worldwide died of this disease in 2020. Apparently, the prognostic markers currently used in the clinic are not sufficient to determine the most appropriate treatment. For this reason, great efforts have been made in recent years to identify new molecular biomarkers that will allow more precise and personalized therapeutic decisions in both primary and recurrent breast cancers. These molecular biomarkers include genetic and post-transcriptional alterations, changes in protein expression, as well as metabolic, immunological or microbial changes identified by multiple omics technologies (e.g., genomics, epigenomics, transcriptomics, proteomics, glycomics, metabolomics, lipidomics, immunomics and microbiomics). This review summarizes studies based on omics analysis that have identified new biomarkers for diagnosis, patient stratification, differentiation between stages of tumor development (initiation, progression, and metastasis/recurrence), and their relevance for treatment selection. Furthermore, this review highlights the importance of clinical trials based on multiomics studies and the need to advance in this direction in order to establish personalized therapies and prolong disease-free survival of these patients in the future.
2023-12-19T00:00:00ZMechanism of the lifespan extension induced by submaximal SERCA inhibition in C. elegansGarcía Casas, PalomaÁlvarez Illera, María PilarFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662482024-02-14T20:00:36Z2021-01-01T00:00:00ZWe have reported recently that submaximal inhibition of the Sarco Endoplasmic Reticulum Ca2+ ATPase
(SERCA) produces an increase in the lifespan of C. elegans worms. We have explored here the mechanism of this increased survival by studying the effect of SERCA inhibition in several mutants of signaling pathways related to longevity. Our data show that the mechanism of the effect is unrelated with the insulin signaling pathway or the sirtuin activity, because SERCA inhibitors increased lifespan similarly in mutants of these pathways. However, the effect required functional mitochondria and both the AMP kinase and TOR pathways, as the SERCA inhibitors were ineffective in the corresponding mutants. The same effects were obtained after reducing SERCA expression with submaximal RNAi treatment. The SERCA inhibitors did not induce ER-stress at the concentrations used, and their effect was not modified by inactivation of the OP50 bacterial food. Altogether, our data suggest that the effect may be due to a reduced ER-mitochondria Ca2+ transfer acting via AMPK activation and mTOR inhibition to promote survival.
2021-01-01T00:00:00ZRegulation of inositol 1,4,5-trisphosphate-induced Ca2+ release from the endoplasmic reticulum by AMP-activated kinase modulatorsArias del Val, JessicaSanto Domingo Mayoral, JaimeGarcía Casas, PalomaÁlvarez Illera, María PilarNúñez Galindo, AntonioWiederkehr, AndreasFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662472024-02-14T20:00:34Z2019-01-01T00:00:00ZThe 5' AMP-activated protein kinase (AMPK) is a nutrient-sensitive kinase that plays a key role in the control of cellular energy metabolism. We have explored here the relationship between AMPK and Ca2+ signaling by looking at the effect of an AMPK activator (A769662) and an AMPK inhibitor (dorsomorphin) on histamine induced Ca2+-release from the endoplasmic reticulum (ER) in HeLa cells. Our data show that incubation with A769662 (EC50=29 μM) inhibited histamine-induced Ca2+-release from the ER in intact cells, as well as inositol-1,4,5-trisphosphate (IP3)-induced Ca2+ release in permeabilized cells. On the contrary, dorsomorphin (EC50=0.4 μM) activated both histamine and IP3-induced Ca2+-release and reversed the effect of A769662. These results suggest a direct effect of AMPK regulation on IP3 receptor (IP3R) function. A phosphoproteomic study did not reveal changes in IP3R phosphorylation, but showed significant changes in phosphorylation of proteins placed upstream in the IP3R interactome and in several proteins related with Ca2+ metabolism, which could be candidates to mediate the effects observed. In conclusion, our data suggest that AMPK negatively regulates IP3R. This effect constitutes a novel and very important link between Ca2+ signaling and the AMPK pathway.
2019-01-01T00:00:00ZSERCA inhibition improves lifespan and healthspan in a chemical model of Parkinson disease in Caenorhabditis elegansRomero-Sanz, SilviaCaldero Escudero, ElenaÁlvarez Illera, María PilarSanto Domingo Mayoral, JaimeFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662372024-02-13T20:00:42Z2023-01-01T00:00:00ZIntroduction: The high prevalence of neurodegenerative diseases in our population and the lack of effective treatments encourage the search for new therapeutic targets for these pathologies. We have recently described that submaximal inhibition of the Sarco-Endoplasmic Reticulum Ca2+ ATPase
(SERCA), the main responsible for ER calcium storage, is able to increase lifespan in Caenorhabditis elegans worms by mechanisms involving mitochondrial metabolism and nutrient-sensitive pathways.
Methods: We have studied here the effects of submaximal SERCA inhibition in a chemical model of Parkinson’s disease (PD) induced in C. elegans worms by treatment with the mitochondrial complex I inhibitor rotenone. For specific SERCA inhibition,we treated worms with RNAi against sca-1, the sole orthologue of SERCA in C. elegans. Results and Discussion: Our results show that rotenone produces alterations in worms that include decreased lifespan, smaller size, reduced fertility, decreased
motility, defecation and pumping rate, increased mitochondrial ROS production, reduced mitochondrial membrane potential and oxygen consumption rate, altered mitochondrial structure, and altered ethanol preference in behavioral studies. Most of these alterations were either fully or partially reversed in worms treated with sca-1 RNAi, suggesting that SERCA inhibition could be a novel pharmacological target in the
prevention or treatment of neurodegeneration.
2023-01-01T00:00:00ZArrhythmic Effects Evaluated on Caenorhabditis elegans: The Case of Polypyrrole NanoparticlesSrinivasan, Sumithra YasaswiniÁlvarez Illera, María PilarKukhtar, DmytroBenseny-Cases, NúriaCerón, JuliánÁlvarez Martín, JavierFonteriz García, Rosalba InésMontero Zoccola, María TeresaLaromaine, Annahttps://uvadoc.uva.es/handle/10324/662362024-02-13T20:00:40Z2023-01-01T00:00:00ZExperimental studies and clinical trials of nanoparticles for treating diseases are increasing continuously.
However, the reach to the market does not correlate with these efforts due to the enormous cost, several years of development, and off-target effects like cardiotoxicity. Multicellular organisms such as the Caenorhabditis elegans (C. elegans) can bridge the gap between in vitro and vertebrate testing as they can provide extensive information on systemic toxicity and specific harmful effects through facile experimentation following 3R EU directives on animal use. Since the nematodes’ pharynx shares similarities with the human heart, we assessed the general and pharyngeal effects of drugs and
polypyrrole nanoparticles (Ppy NPs) using C. elegans. The evaluation of FDA-approved drugs, such as Propranolol and Racepinephrine reproduced the arrhythmic behavior reported in humans and supported the use of this small animal model. Consequently, Ppy NPs were evaluated due to their research interest in cardiac arrhythmia treatments. The NPs’ biocompatibility was confirmed by assessing survival, growth and development, reproduction, and transgenerational toxicity in C. elegans. Interestingly, the NPs increased the pharyngeal pumping rate of C. elegans in two slow-pumping mutant strains, JD21 and DA464. Moreover, the NPs increased the pumping rate over time, which sustained up to a day post-excretion. By measuring pharyngeal calcium levels, we found that the impact of Ppy NPs on the pumping rate could be mediated through calcium signaling. Thus, evaluating arrhythmic effects in C. elegans offers a simple system to test drugs and nanoparticles, as elucidated through Ppy NPs.
2023-01-01T00:00:00ZModeling Alzheimer’s Disease in Caenorhabditis elegansÁlvarez Martín, JavierÁlvarez Illera, María PilarSanto Domingo Mayoral, JaimeFonteriz García, Rosalba InésMontero Zoccola, María Teresahttps://uvadoc.uva.es/handle/10324/662342024-02-13T20:00:39Z2022-01-01T00:00:00ZAlzheimer’s disease (AD) is the most frequent cause of dementia. After decades of research, we know the importance of the accumulation of protein aggregates such as -amyloid peptide and phosphorylated tau. We also know that mutations in certain proteins generate early-onset Alzheimer’s disease (EOAD), and many other genes modulate the disease in its sporadic form. However, the precise molecular mechanisms underlying AD pathology are still unclear. Because of ethical limitations, we need to use animal models to investigate these processes. The nematode Caenorhabditis elegans has received considerable attention in the last 25 years, since the first AD models overexpressing A peptide were described. We review here the main results obtained using this model to study AD. We include works studying the basic molecular mechanisms of the disease, as well as those searching for new therapeutic targets. Although this model also has important limitations, the ability of this nematode to generate knock-out or overexpression models of any gene, single or combined, and to carry out toxicity, recovery or survival studies in short timeframes with many individuals and at low cost is difficult to overcome. We can predict that its use as a model for various diseases will certainly continue to increase.
2022-01-01T00:00:00ZThe Mitochondrial Na+/Ca2+ Exchanger Inhibitor CGP37157 Preserves Muscle Structure and Function to Increase Lifespan and Healthspan in Caenorhabditis elegansGarcía Casas, PalomaÁlvarez Illera, María PilarGómez-Orte, EvaCabello, JuanFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662332024-02-13T20:00:38Z2021-01-01T00:00:00ZWe have reported recently that the mitochondrial Na+/Ca2+ exchanger inhibitor CGP37157 extends lifespan in Caenorhabditis elegans by a mechanism involving mitochondria, the TOR pathway and the insulin/IGF1 pathway. Here we show that CGP37157 significantly improved the evolution with age of the sarcomeric regular structure, delaying development of sarcopenia in C. elegans body wall muscle and
increasing the average and maximum speed of the worms. Similarly, CGP37157 favored the maintenance of a regular mitochondrial structure during aging. We have also investigated further the mechanism of the effect of CGP37157 by studying its effect in mutants of aak-1;aak-2/AMP-activated kinase, sir-2.1/sirtuin, rsks-1/S6 kinase and daf-16/FOXO. We found that this compound was still effective increasing lifespan in all these mutants, indicating that these pathways are not involved in the effect. We have then monitored pharynx cytosolic and mitochondrial Ca2+ signalling and our results suggest that CGP37157 is probably inhibiting not only the mitochondrial Na+/Ca2+ exchanger, but also Ca2+ entry through the plasma membrane. Finally, a transcriptomic study detected that CGP37157 induced changes in lipid metabolism enzymes and a four-fold increase in the expression of ncx-6, one of the C. elegans mitochondrial Na+/Ca2+ exchangers. In summary, CGP37157 increases both lifespan and healthspan by a mechanism involving changes in cytosolic and mitochondrial Ca2+ homeostasis. Thus, Ca2+ signalling could be
a promising target to act on aging.
2021-01-01T00:00:00ZMitochondrial Ca2+ Dynamics in MCU Knockout C. elegans WormsÁlvarez Illera, María PilarGarcía Casas, PalomaFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662322024-02-13T20:00:36Z2020-01-01T00:00:00ZMitochondrial [Ca2+] plays an important role in the regulation of mitochondrial function, controlling ATP production and apoptosis triggered by mitochondrial Ca2+ overload. This regulation depends on Ca2+ entry into the mitochondria during cell activation processes, which is thought to occur through the mitochondrial Ca2+ uniporter (MCU). Here, we have studied the mitochondrial Ca2+ dynamics in control and MCU-defective C. elegans worms in vivo, by using worms expressing mitochondrially-targeted YC3.60 yellow cameleon in pharynx muscle. Our data show that the small mitochondrial Ca2+ oscillations that occur during normal physiological activity of the pharynx were very similar in both control and MCU-defective worms, except for some kinetic differences that could mostly be explained by changes in neuronal stimulation of the pharynx. However, direct pharynx muscle stimulation with carbachol triggered a large and prolonged increase in mitochondrial [Ca2+] that was much larger in control worms than in MCU-defective worms. This suggests that MCU is necessary for the fast mitochondrial Ca2+ uptake induced by large cell stimulations. However, low-amplitude mitochondrial Ca2+ oscillations occurring under more physiological conditions are independent of the MCU and use a different Ca2+ pathway.
2020-01-01T00:00:00ZThe Role of Ca2+ Signaling in Aging and Neurodegeneration: Insights from Caenorhabditis elegans ModelsÁlvarez Martín, JavierÁlvarez Illera, María PilarGarcía Casas, PalomaFonteriz García, Rosalba InésMontero Zoccola, María Teresahttps://uvadoc.uva.es/handle/10324/662312024-02-13T20:00:35Z2020-01-01T00:00:00ZCa2+ is a ubiquitous second messenger that plays an essential role in physiological processes such as muscle contraction, neuronal secretion, and cell proliferation or di erentiation. There is ample evidence that the dysregulation of Ca2+ signaling is one of the key events in the development of neurodegenerative processes, an idea called the “calcium hypothesis” of neurodegeneration. Caenorhabditis elegans (C. elegans) is a very good model for the study of aging and neurodegeneration. In fact, many of the signaling pathways involved in longevity were first discovered in this nematode, and many models of neurodegenerative diseases have also been developed therein, either through mutations in the worm genome or by expressing human proteins involved in neurodegeneration (beta -amyloid, alpha-synuclein, polyglutamine, or others) in defined worm tissues. The worm is completely transparent throughout its whole life, which makes it possible to carry out Ca2+ dynamics studies in vivo at any time, by expressing Ca2+ fluorescent probes in defined worm tissues, and even in specific organelles such as mitochondria. This review will summarize the evidence obtained using this model organism to understand the role of Ca2+ signaling in aging and neurodegeneration.
2020-01-01T00:00:00ZThe Neuroprotector Benzothiazepine CGP37157 Extends Lifespan in C. elegans WormsGarcía Casas, PalomaArias del Val, JessicaÁlvarez Illera, María PilarWojnicz, Anetade los Ríos, CristobalFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662302024-02-13T20:00:33Z2019-01-01T00:00:00ZThe benzothiazepine CGP37157 has shown neuroprotective effects in several in vitro models of excitotoxicity involving dysregulation of intracellular Ca2+ homeostasis. Although its mechanism of neuroprotection is unclear, it is probably related with some of its effects on Ca2C homeostasis. CGP37157 is a well-known inhibitor of the mitochondrial Na+/Ca2+ exchanger (mNCX). However, it is not very specific and also blocks several other Ca2+ channels and transporters, including voltage gated
Ca2+ channels, plasma membrane Na+/Ca2+ exchanger and the Ca2+ homeostasis modulator 1 channel (CALHM1). In the present work, we have studied if CGP37157 could also induce changes in life expectancy. We now report that CGP37157 extends C. elegans lifespan by 10%–15% with a bell-shaped concentration response, with high concentrations producing no effect. The effect was even larger
(25% increase in life expectancy) in worms fed with heat-inactivated bacteria. The worm CGP37157 concentration producing maximum effect was measured by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and was close to the IC50 for inhibition of the Na+/Ca2+ exchanger. CGP37157 also extended the lifespan in eat-2 mutants (a model for caloric restriction), suggesting that caloric restriction is not involved in the mechanism of lifespan extension. Actually,
CGP37157 produced no effect in mutants of the TOR pathway (daf15/unc24) or the insulin/insulin-like growth factor-1 (IGF-1) pathway (daf-2), indicating that the effect involves these pathways. Moreover, CGP37157 was also ineffective in nuo-6 mutants, which have a defect in the mitochondrial respiratory chain complex I. Since it has been described that neuroprotection by this compound in cell cultures is
abolished by mitochondrial inhibitors, this suggests that life extension in C. elegans and neuroprotection in cell cultures may share a similar mechanism involving mitochondria.
2019-01-01T00:00:00ZInhibition of Sarco-Endoplasmic Reticulum Ca2+ ATPase Extends the Lifespan in C. elegans WormsGarcía Casas, PalomaÁlvarez Illera, María PilarArias del Val, JessicaFonteriz García, Rosalba InésMontero Zoccola, María TeresaÁlvarez Martín, Javierhttps://uvadoc.uva.es/handle/10324/662292024-02-13T20:00:32Z2018-01-01T00:00:00ZThe sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) refills the endoplasmic reticulum (ER) with Ca2+ up to the millimolar range and is therefore the main controller of the ER [Ca2+] level ([Ca2+]ER), which has a key role in the modulation of cytosolic Ca2+ signaling and ER-mitochondria Ca2+ transfer. Given that both cytosolic and mitochondrial Ca2+ dynamics strongly interplay with energy metabolism and nutrient sensitive pathways, both of them involved in the aging process, we have studied the effect of SERCA inhibitors on lifespan in C. elegans. We have used thapsigargin and 2,5-Di-tert-butylhydroquinone (2,5-BHQ) as SERCA inhibitors, and the inactive analog 2,6-Di-tert-butylhydroquinone (2,6-BHQ) as a control for 2,5-BHQ. Every drug was administered to the worms either directly in the agar or via an inclusion compound with γ-cyclodextrin. The results show that 2,6-BHQ produced a small but significant
increase in survival, perhaps because of its antioxidant properties. However, 2,5-BHQ produced in all the conditions a much higher increase in lifespan, and the potent and specific SERCA inhibitor thapsigargin also extended the lifespan. The effects of 2,5-BHQ and thapsigargin had a bell-shaped concentration dependence, with a maximum effect at a certain dose and smaller or even toxic effects at higher concentrations. Our data show therefore that submaximal inhibition of SERCA pumps has a pro-longevity effect, suggesting that Ca2+ signaling plays an important role in the aging process and that it could be a promising novel target pathway to act on aging.
2018-01-01T00:00:00ZPharmacological Approaches for the Modulation of the Potassium Channel KV4.x and KChIPsCercós, PilarPeraza, Diego A.Benito-Bueno, Angela deSocuéllamos, Paula G.Aziz-Nignan, AbdoulArrechaga-Estévez, DarielBeato, EscarlePeña-Acevedo, EmilioAlbert, ArmandoGonzález-Vera, Juan A.Rodríguez, YoelMartín-Martínez, MercedesValenzuela, CarmenGutiérrez-Rodríguez, Martahttps://uvadoc.uva.es/handle/10324/660332024-02-08T20:00:58Z2021-01-01T00:00:00ZIon channels are macromolecular complexes present in the plasma membrane and intracellular organelles of cells. Dysfunction of ion channels results in a group of disorders named channelopathies, which represent an extraordinary challenge for study and treatment. In this review, we will focus on voltage-gated potassium channels (KV), specifically on the KV4-family. The activation of these channels generates outward currents operating at subthreshold membrane potentials as recorded from myocardial cells (ITO, transient outward current) and from the somata of hippocampal neurons (ISA). In the heart, KV4 dysfunctions are related to Brugada syndrome, atrial fibrillation, hypertrophy, and heart failure. In hippocampus, KV4.x channelopathies are linked to schizophrenia, epilepsy, and Alzheimer's disease. KV4.x channels need to assemble with other accessory subunits (β) to fully reproduce the ITO and ISA currents. β Subunits affect channel gating and/or the traffic to the plasma membrane, and their dysfunctions may influence channel pharmacology. Among KV4 regulatory subunits, this review aims to analyze the KV4/KChIPs interaction and the effect of small molecule KChIP ligands in the A-type currents generated by the modulation of the KV4/KChIP channel complex. Knowledge gained from structural and functional studies using activators or inhibitors of the potassium current mediated by KV4/KChIPs will better help understand the underlying mechanism involving KV4-mediated-channelopathies, establishing the foundations for drug discovery, and hence their treatments.
2021-01-01T00:00:00Z