85 research outputs found

    Glutamate induces autophagy via the two-pore channels in neural cells

    Get PDF
    NAADP (nicotinic acid adenine dinucleotide phosphate) has been proposed as a second messenger for glutamate in neuronal and glial cells via the activation of the lysosomal Ca2+ channels TPC1 and TPC2. However, the activities of glutamate that are mediated by NAADP remain unclear. In this study, we evaluated the effect of glutamate on autophagy in astrocytes at physiological, non-toxic concentration. We found that glutamate induces autophagy at similar extent as NAADP. By contrast, the NAADP antagonist NED-19 or SiRNA-mediated inhibition of TPC1/2 decreases autophagy induced by glutamate, confirming a role for NAADP in this pathway. The involvement of TPC1/2 in glutamate-induced autophagy was also confirmed in SHSY5Y neuroblastoma cells. Finally, we show that glutamate leads to a NAADP-dependent activation of AMPK, which is required for autophagy induction, while mTOR activity is not affected by this treatment. Taken together, our results indicate that glutamate stimulates autophagy via NAADP/TPC/AMPK axis, providing new insights of how Ca2+ signalling glutamate-mediated can control the cell metabolism in the central nervous system

    Liposomes loaded with everolimus and coated with hyaluronic acid: A promising approach for lung fibrosis

    Get PDF
    Chronic lung allograft dysfunction (CLAD) and interstitial lung disease associated with collagen tissue diseases (CTD-ILD) are two end-stage lung disorders in which different chronic triggers induce activation of myo-/fibroblasts (LFs). Everolimus, an mTOR inhibitor, can be adopted as a potential strategy for CLAD and CTD-ILD, however it exerts important side effects. This study aims to exploit nanomedicine to reduce everolimus side effects encapsulating it inside liposomes targeted against LFs, expressing a high rate of CD44. PEGylated liposomes were modified with high molecular weight hyaluronic acid and loaded with everolimus (PEG-LIP(ev)-HA400kDa). Liposomes were tested by in vitro experiments using LFs derived from broncholveolar lavage (BAL) of patients affected by CLAD and CTD-ILD, and on alveolar macrophages (AM) and lymphocytes isolated, respectively, from BAL and peripheral blood. PEG-LIP-HA400kDa demonstrated to be specific for LFs, but not for CD44-negative cells, and after loading everolimus, PEG-LIP(ev)-HA400kDa were able to arrest cell cycle arrest and to decrease phospho-mTOR level. PEG-LIP(ev)-HA400kDa showed anti-inflammatory effect on immune cells. This study opens the possibility to use everolimus in lung fibrotic diseases, demonstrating that our lipids-based vehicles can vehicle everolimus inside cells exerting the same drug molecular effect, not only in LFs, but also in immune cells

    Effective Synergy of Sorafenib and Nutrient Shortage in Inducing Melanoma Cell Death through Energy Stress

    Get PDF
    Skin melanoma is one of the most aggressive and difficult-to-treat human malignancies, characterized by poor survival rates, thus requiring urgent novel therapeutic approaches. Although metabolic reprogramming has represented so far, a cancer hallmark, accumulating data indicate a high plasticity of cancer cells in modulating cellular metabolism to adapt to a heterogeneous and continuously changing microenvironment, suggesting a novel therapeutic approach for dietary manipulation in cancer therapy. To this aim, we exposed melanoma cells to combined nutrient-restriction/sorafenib. Results indicate that cell death was efficiently induced, with apoptosis representing the prominent feature. In contrast, autophagy was blocked in the final stage by this treatment, similarly to chloroquine, which also enhanced melanoma cell sensitization to combined treatment. Energy stress was evidenced by associated treatment with mitochondrial dysfunction and glycolysis impairment, suggesting metabolic stress determining melanoma cell death. A reduction of tumor growth after cycles of intermittent fasting together with sorafenib treatment was also observed in vivo, reinforcing that the nutrient shortage can potentiate anti-melanoma therapy. Our findings showed that the restriction of nutrients by intermittent fasting potentiates the effects of sorafenib due to the modulation of cellular metabolism, suggesting that it is possible to harness the energy of cancer cells for the treatment of melanoma

    Extensive myocardial infiltration by hemopoietic precursors in a patient with myelodysplastic syndrome

    Get PDF
    BACKGROUND: Although myocardial infiltration with leukemic blasts is a known finding in patients with acute leukemia, this phenomenon in myelodysplasia is not reported in the literature. Cardiac symptoms in patients with myelodysplasia are often due to anemia and may be due to iron overload and side effects of therapy. CASE PRESENTATION: Herein we report the first case of neoplastic infiltration of the heart with associated myocardial necrosis in a patient with myelodysplasia. It was associated with unicellular and multifocal geographic areas of necrosis in the left ventricle and the interventricular septum. It is likely that cardiac compromise in our patient was due to a combination of restrictive cardiomyopathy due to leukemic infiltration, concomitant anemia, cardiac dilatation, conduction blocks and myocardial necrosis. Myocardial necrosis was most likely due to a combination of ischemic damage secondary to anemia and prolonged hypotension and extensive leukemic infiltration. Markedly rapid decrease in ejection fraction from 66% to 33% also suggests the role of ischemia, since leukemic infiltration is not expected to cause this degree of systolic dysfunction over a 24-hour period. The diagnosis was not suspected during life due to concomitant signs and symptoms of anemia, pulmonary infections, and pericardial and pleural effusions. The patient succumbed to cardiac failure. CONCLUSION: Hemopoietic cell infiltration was not considered in the differential diagnosis and contributed to this patient's morbidity and mortality. This case highlights the clinical importance of considering myocardial infiltration in patients with myelodysplasia and cardiac symptoms

    Lifespan-Extending Effects of Royal Jelly and Its Related Substances on the Nematode Caenorhabditis elegans

    Get PDF
    One of the most important challenges in the study of aging is to discover compounds with longevity-promoting activities and to unravel their underlying mechanisms. Royal jelly (RJ) has been reported to possess diverse beneficial properties. Furthermore, protease-treated RJ (pRJ) has additional pharmacological activities. Exactly how RJ and pRJ exert these effects and which of their components are responsible for these effects are largely unknown. The evolutionarily conserved mechanisms that control longevity have been indicated. The purpose of the present study was to determine whether RJ and its related substances exert a lifespan-extending function in the nematode Caenorhabditis elegans and to gain insights into the active agents in RJ and their mechanism of action.We found that both RJ and pRJ extended the lifespan of C. elegans. The lifespan-extending activity of pRJ was enhanced by Octadecyl-silica column chromatography (pRJ-Fraction 5). pRJ-Fr.5 increased the animals' lifespan in part by acting through the FOXO transcription factor DAF-16, the activation of which is known to promote longevity in C. elegans by reducing insulin/IGF-1 signaling (IIS). pRJ-Fr.5 reduced the expression of ins-9, one of the insulin-like peptide genes. Moreover, pRJ-Fr.5 and reduced IIS shared some common features in terms of their effects on gene expression, such as the up-regulation of dod-3 and the down-regulation of dod-19, dao-4 and fkb-4. 10-Hydroxy-2-decenoic acid (10-HDA), which was present at high concentrations in pRJ-Fr.5, increased lifespan independently of DAF-16 activity.These results demonstrate that RJ and its related substances extend lifespan in C. elegans, suggesting that RJ may contain longevity-promoting factors. Further analysis and characterization of the lifespan-extending agents in RJ and pRJ may broaden our understanding of the gene network involved in longevity regulation in diverse species and may lead to the development of nutraceutical interventions in the aging process

    Artificial intelligence of imaging and clinical neurological data for predictive, preventive and personalized (P3) medicine for Parkinson Disease: the NeuroArtP3 protocol for a multi-center research study

    Get PDF
    Background The burden of Parkinson Disease (PD) represents a key public health issue and it is essential to develop innovative and cost-effective approaches to promote sustainable diagnostic and therapeutic interventions. In this perspective the adoption of a P3 (predictive, preventive and personalized) medicine approach seems to be pivotal. The NeuroArtP3 (NET-2018-12366666) is a four-year multi-site project co-funded by the Italian Ministry of Health, bringing together clinical and computational centers operating in the field of neurology, including PD. Objective The core objectives of the project are: i) to harmonize the collection of data across the participating centers, ii) to structure standardized disease-specific datasets and iii) to advance knowledge on disease’s trajectories through machine learning analysis. Methods The 4-years study combines two consecutive research components: i) a multi-center retrospective observational phase; ii) a multi-center prospective observational phase. The retrospective phase aims at collecting data of the patients admitted at the participating clinical centers. Whereas the prospective phase aims at collecting the same variables of the retrospective study in newly diagnosed patients who will be enrolled at the same centers. Results The participating clinical centers are the Provincial Health Services (APSS) of Trento (Italy) as the center responsible for the PD study and the IRCCS San Martino Hospital of Genoa (Italy) as the promoter center of the NeuroartP3 project. The computational centers responsible for data analysis are the Bruno Kessler Foundation of Trento (Italy) with TrentinoSalute4.0 –Competence Center for Digital Health of the Province of Trento (Italy) and the LISCOMPlab University of Genoa (Italy). Conclusions The work behind this observational study protocol shows how it is possible and viable to systematize data collection procedures in order to feed research and to advance the implementation of a P3 approach into the clinical practice through the use of AI models

    Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

    Get PDF

    Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

    Get PDF
    In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field
    corecore