Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32.366
Filtrar
2.
Pathog Dis ; 78(4)2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32667665

RESUMO

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) around the world has led to a pandemic with high morbidity and mortality. However, there are no effective drugs to prevent and treat the disease. Transcriptome-based drug repositioning, identifying new indications for old drugs, is a powerful tool for drug development. Using bronchoalveolar lavage fluid transcriptome data of COVID-19 patients, we found that the endocytosis and lysosome pathways are highly involved in the disease and that the regulation of genes involved in neutrophil degranulation was disrupted, suggesting an intense battle between SARS-CoV-2 and humans. Furthermore, we implemented a coexpression drug repositioning analysis, cogena, and identified two antiviral drugs (saquinavir and ribavirin) and several other candidate drugs (such as dinoprost, dipivefrine, dexamethasone and (-)-isoprenaline). Notably, the two antiviral drugs have also previously been identified using molecular docking methods, and ribavirin is a recommended drug in the diagnosis and treatment protocol for COVID pneumonia (trial version 5-7) published by the National Health Commission of the P.R. of China. Our study demonstrates the value of the cogena-based drug repositioning method for emerging infectious diseases, improves our understanding of SARS-CoV-2-induced disease, and provides potential drugs for the prevention and treatment of COVID-19 pneumonia.


Assuntos
Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Reposicionamento de Medicamentos , Pneumonia Viral/tratamento farmacológico , Ribavirina/farmacologia , Saquinavir/farmacologia , Líquido da Lavagem Broncoalveolar/química , Degranulação Celular/imunologia , Endocitose/imunologia , Perfilação da Expressão Gênica , Humanos , Lisossomos/imunologia , Simulação de Acoplamento Molecular , Ativação de Neutrófilo/imunologia , Pandemias , Transcriptoma
3.
Int J Mol Sci ; 21(14)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668803

RESUMO

In line with SARS and MERS, the SARS-CoV-2/COVID-19 pandemic is one of the largest challenges in medicine and health care worldwide. SARS-CoV-2 infection/COVID-19 provides numerous therapeutic targets, each of them promising, but not leading to the success of therapy to date. Neither an antiviral nor an immunomodulatory therapy in patients with SARS-CoV-2 infection/COVID-19 or pre-exposure prophylaxis against SARS-CoV-2 has proved to be effective. In this review, we try to close the gap and point out the likely relationships among lysosomotropism, increasing lysosomal pH, SARS-CoV-2 infection, and disease process, and we deduce an approach for the treatment and prophylaxis of COVID-19, and cytokine release syndrome (CRS)/cytokine storm triggered by bacteria or viruses. Lysosomotropic compounds affect prominent inflammatory messengers (e.g., IL-1B, CCL4, CCL20, and IL-6), cathepsin-L-dependent viral entry of host cells, and products of lysosomal enzymes that promote endothelial stress response in systemic inflammation. As supported by recent clinical data, patients who have already taken lysosomotropic drugs for other pre-existing conditions likely benefit from this treatment in the COVID-19 pandemic. The early administration of a combination of antivirals such as remdesivir and lysosomotropic drugs, such as the antibiotics teicoplanin or dalbavancin, seems to be able to prevent SARS-CoV-2 infection and transition to COVID-19.


Assuntos
Infecções por Coronavirus/patologia , Lisossomos/metabolismo , Pneumonia Viral/patologia , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Betacoronavirus/isolamento & purificação , Betacoronavirus/fisiologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/patologia , Humanos , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/complicações , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Internalização do Vírus/efeitos dos fármacos
4.
Front Immunol ; 11: 1409, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714335

RESUMO

As the world is severely affected by COVID-19 pandemic, the use of chloroquine and hydroxychloroquine in prevention or for the treatment of patients is allowed in multiple countries but remained at the center of much controversy in recent days. This review describes the properties of chloroquine and hydroxychloroquine, and highlights not only their anti-viral effects but also their important immune-modulatory properties and their well-known use in autoimmune diseases, including systemic lupus and arthritis. Chloroquine appears to inhibit in vitro SARS virus' replication and to interfere with SARS-CoV2 receptor (ACE2). Chloroquine and hydroxychloroquine impede lysosomal activity and autophagy, leading to a decrease of antigen processing and presentation. They are also known to interfere with endosomal Toll-like receptors signaling and cytosolic sensors of nucleic acids, which result in a decreased cellular activation and thereby a lower type I interferons and inflammatory cytokine secretion. Given the antiviral and anti-inflammatory properties of chloroquine and hydroxychloroquine, there is a rational to use them against SARS-CoV2 infection. However, the anti-interferon properties of these molecules might be detrimental, and impaired host immune responses against the virus. This duality could explain the discrepancy with the recently published studies on CQ/HCQ treatment efficacy in COVID-19 patients. Moreover, although these treatments could be an interesting potential strategy to limit progression toward uncontrolled inflammation, they do not appear per se sufficiently potent to control the whole inflammatory process in COVID-19, and more targeted and/or potent therapies should be required at least in add-on.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus/fisiologia , Hidroxicloroquina/uso terapêutico , Pandemias , Replicação Viral/efeitos dos fármacos , Apresentação do Antígeno , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Humanos , Lisossomos/imunologia , Lisossomos/virologia , Peptidil Dipeptidase A/imunologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Receptores Toll-Like/imunologia , Replicação Viral/imunologia
5.
Pestic Biochem Physiol ; 167: 104585, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32527440

RESUMO

Apigenin, is a natural compound that found in high amounts in vegetables and fruits. This natural flavone has shown strong cardioprotective effects in animal and clinical studies. Due to cardioprotective effects of apigenin in previous studies, we hypothesized that apigenin protects isolated cardiomyocytes from aluminum phosphide(AlP)-induced toxicity as the most common disturbances after exposure with this agent. By using of biochemical and flowcytometry techniques; cell viability, reactive oxygen species (ROS) generation, mitochondria membrane potential (MMP), lysosomal membrane integrity, malondialdehyde (MDA) and oxidized/reduced glutathione (GSH/GSSG) content were measured in rat heart isolated cardiomyocytes. Our results showed that the administration of apigenin (5-100 µM) efficiently decreased (P < .05) cytotoxicity, oxidative, lysosomal and mitochondrial damages induced by AlP (20 µg/ml) in isolated cardiomyocytes. Taken together, apigenin protected the cardiomyocytes against AlP toxicity via the protection of mitochondria and lysosome mediated by its antioxidant properties.


Assuntos
Apigenina , Miócitos Cardíacos , Compostos de Alumínio , Animais , Apoptose , Lisossomos , Estresse Oxidativo , Fosfinas , Ratos , Espécies Reativas de Oxigênio
6.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 32(4): 504-507, 2020 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-32527363

RESUMO

Sepsis is a life-threatening systemic inflammatory response syndrome (SIRS) caused by the host's maladjustment response to infection, which eventually leads to septic shock and multiple organ failure. Pancreatic injury was found to be an important pathological change in sepsis. Autophagy is a crucial way to maintain the normal metabolism of cell substances and energy, which plays an important role in many diseases. Recent studies have found that autophagy plays a dual role in pancreatic injury in sepsis. Moderate autophagy can protect the pancreas and reduce the injury, while excessive autophagy can cause apoptosis-related autophagic cell death and aggravate the pancreatic injury. In sepsis, activated nuclear factor-κB (NF-κB) has a promoting effect on autophagy, and lysosome associated membrane protein (LAMP) degradation can result in impaired autophagy flux and aggravate pancreatic injury. The exploration of the mechanism of autophagy in pancreatic injury of sepsis will help to restore the normal autophagy function, so as to find a new target for the treatment of pancreatic injury of sepsis.


Assuntos
Autofagia , Pâncreas/lesões , Sepse , Apoptose , Humanos , Lisossomos , NF-kappa B
7.
F1000Res ; 92020.
Artigo em Inglês | MEDLINE | ID: mdl-32518628

RESUMO

A complex molecular machinery converges on the surface of lysosomes to ensure that the growth-promoting signaling mediated by mechanistic target of rapamycin complex 1 (mTORC1) is tightly controlled by the availability of nutrients and growth factors. The final step in this activation process is dependent on Rheb, a small GTPase that binds to mTOR and allosterically activates its kinase activity. Here we review the mechanisms that determine the subcellular localization of Rheb (and the closely related RhebL1 protein) as well as the significance of these mechanisms for controlling mTORC1 activation. In particular, we explore how the relatively weak membrane interactions conferred by C-terminal farnesylation are critical for the ability of Rheb to activate mTORC1. In addition to supporting transient membrane interactions, Rheb C-terminal farnesylation also supports an interaction between Rheb and the δ subunit of phosphodiesterase 6 (PDEδ). This interaction provides a potential mechanism for targeting Rheb to membranes that contain Arl2, a small GTPase that triggers the release of prenylated proteins from PDEδ. The minimal membrane targeting conferred by C-terminal farnesylation of Rheb and RhebL1 distinguishes them from other members of the Ras superfamily that possess additional membrane interaction motifs that work with farnesylation for enrichment on the specific subcellular membranes where they engage key effectors. Finally, we highlight diversity in Rheb membrane targeting mechanisms as well as the potential for alternative mTORC1 activation mechanisms across species.


Assuntos
Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteína Enriquecida em Homólogo de Ras do Encéfalo/metabolismo , Transdução de Sinais , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas ras/metabolismo
8.
Cells ; 9(6)2020 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-32545714

RESUMO

There is no vaccine or specific antiviral treatment for COVID-19, which is causing a global pandemic. One current focus is drug repurposing research, but those drugs have limited therapeutic efficacies and known adverse effects. The pathology of COVID-19 is essentially unknown. Without this understanding, it is challenging to discover a successful treatment to be approved for clinical use. This paper addresses several key biological processes of reactive oxygen, halogen and nitrogen species (ROS, RHS and RNS) that play crucial physiological roles in organisms from plants to humans. These include why superoxide dismutases, the enzymes to catalyze the formation of H2O2, are required for protecting ROS-induced injury in cell metabolism, why the amount of ROS/RNS produced by ionizing radiation at clinically relevant doses is ~1000 fold lower than the endogenous ROS/RNS level routinely produced in the cell and why a low level of endogenous RHS plays a crucial role in phagocytosis for immune defense. Herein we propose a plausible amplification mechanism in immune defense: ozone-depleting-like halogen cyclic reactions enhancing RHS effects are responsible for all the mentioned physiological functions, which are activated by H2O2 and deactivated by NO signaling molecule. Our results show that the reaction cycles can be repeated thousands of times and amplify the RHS pathogen-killing (defense) effects by 100,000 fold in phagocytosis, resembling the cyclic ozone-depleting reactions in the stratosphere. It is unraveled that H2O2 is a required protective signaling molecule (angel) in the defense system for human health and its dysfunction can cause many diseases or conditions such as autoimmune disorders, aging and cancer. We also identify a class of potent drugs for effective treatment of invading pathogens such as HIV and SARS-CoV-2 (COVID-19), cancer and other diseases, and provide a molecular mechanism of action of the drugs or candidates.


Assuntos
Antivirais/química , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/imunologia , Compostos Heterocíclicos/uso terapêutico , Hidrocarbonetos Halogenados/uso terapêutico , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/imunologia , Animais , Antivirais/uso terapêutico , Infecções por Coronavirus/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Lisossomos/efeitos dos fármacos , Pandemias , Fagocitose , Pneumonia Viral/metabolismo , Explosão Respiratória/efeitos dos fármacos , Transdução de Sinais
9.
Cell Prolif ; 53(7): e12813, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32515860

RESUMO

OBJECTIVES: Accumulating studies have investigated the PM2.5-induced pulmonary toxicity, while gaps still remain in understanding its toxic mechanism. Due to its high specific surface area and adsorption capacity similar to nanoparticles, PM2.5 acts as a significant carrier of metals in air and then leads to altered toxic effects. In this study, we aimed to use CBs and Ni as model materials to investigate the autophagy changes and pulmonary toxic effects at 30 days following intratracheal instillation of CBs-Ni mixture. MATERIALS AND METHODS: Groups of mice were instilled with 100 µL normal saline (NS), 20 µg CBs, and 4 µg Ni or CBs-Ni mixture, respectively. At 7 and 30 days post-instillation, all the mice were weighed and then sacrificed. The evaluation system was composed of the following: (a) autophagy and lysosomal function assessment, (b) trace element biodistribution observation in lungs, (c) pulmonary lavage biomedical analysis, (d) lung histopathological evaluation, (e) coefficient analysis of major organs and (f) CBs-Ni interaction and cell proliferation assessment. RESULTS: We found that after CBs-Ni co-exposure, no obvious autophagy and lysosomal dysfunction or pulmonary toxicity was detected, along with complete clearance of Ni from lung tissues as well as recovery of biochemical indexes to normal range. CONCLUSIONS: We conclude that the damaged autophagy and lysosomal function, as well as physiological function, was repaired at 30 days after exposure of CBs-Ni. Our findings provide a new idea for scientific assessment of the impact of fine particles on environment and human health, and useful information for the comprehensive treatment of air pollution.


Assuntos
Autofagia/efeitos dos fármacos , Carbono/efeitos adversos , Pneumopatias/induzido quimicamente , Pulmão/efeitos dos fármacos , Metais/efeitos adversos , Animais , Linhagem Celular , Pulmão/metabolismo , Pneumopatias/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Tamanho da Partícula , Células RAW 264.7 , Distribuição Tecidual
10.
Sci Total Environ ; 734: 139229, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32450398

RESUMO

The induced membrane damage is a key mechanism for the cytotoxicity of graphene nanosheets (GNSs). In this research, the physical interaction of GNSs on model membranes was investigated using artificial membranes and plasma membrane vesicles. The effects of the GNSs on plasma membrane, lysosomal and mitochondrial membranes were investigated using rat basophilic leukemia (RBL2H3) cells via lactate dehydrogenase (LDH) assay, acridine orange staining and JC-1 probe, respectively. The physical interaction with model membranes was dominated by electrostatic forces, and the adhered GNSs disrupted the membrane. The degree of physical membrane disruption was quantified by the quartz crystal microbalance with dissipation (QCM-D), confirming the serious membrane disruption. The internalized GNSs were mainly distributed in the lysosomes. They caused plasma membrane leakage, increased the lysosomal membrane permeability (LMP), and depolarized the mitochondrial membrane potential (MMP). The increased cellular levels of reactive oxygen species (ROS) were also detected after GNS exposure. The combination of physical interaction and the excess ROS production damaged the plasma and organelle membranes in living RBL-2H3 cells. The lysosomal and mitochondrial dysfunction, and the oxidative stress further induced cell apoptosis. Specially, the exposure to 25 mg/L GNSs caused severest cell mortality, plasma membrane damage, ROS generation, MMP depolarization and apoptosis. The research findings provide more comprehensive information on the graphene-induced plasma and organelle membrane damage, which is important to understand and predict the cytotoxicity of carbon-based nanomaterials.


Assuntos
Membranas Mitocondriais , Animais , Apoptose , Linhagem Celular Tumoral , Grafite , Lisossomos , Potencial da Membrana Mitocondrial , Ratos , Espécies Reativas de Oxigênio
11.
Int J Antimicrob Agents ; 55(6): 106004, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32361028

RESUMO

SARS-coronavirus 2 is the causal agent of the COVID-19 outbreak. SARS-Cov-2 entry into a cell is dependent upon binding of the viral spike (S) protein to cellular receptor and on cleavage of the spike protein by the host cell proteases such as Cathepsin L and Cathepsin B. CTSL/B are crucial elements of lysosomal pathway and both enzymes are almost exclusively located in the lysosomes. CTSL disruption offers potential for CoVID-19 therapies. The mechanisms of disruption include: decreasing expression of CTSL, direct inhibition of CTSL activity and affecting the conditions of CTSL environment (increase pH in the lysosomes). We have conducted a high throughput drug screen gene expression analysis to identify compounds that would downregulate the expression of CTSL/CTSB. One of the top significant results shown to downregulate the expression of the CTSL gene is amantadine (10uM). Amantadine was approved by the US Food and Drug Administration in 1968 as a prophylactic agent for influenza and later for Parkinson's disease. It is available as a generic drug. Amantadine in addition to downregulating CTSL appears to further disrupt lysosomal pathway, hence, interfering with the capacity of the virus to replicate. It acts as a lysosomotropic agent altering the CTSL functional environment.  We hypothesize that amantadine could decrease the viral load in SARS-CoV-2 positive patients and as such it may serve as a potent therapeutic decreasing the replication and infectivity of the virus likely leading to better clinical outcomes. Clinical studies will be needed to examine the therapeutic utility of amantadine in COVID-19 infection.


Assuntos
Amantadina/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Catepsina L/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Catepsina B/metabolismo , Catepsina L/genética , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Pandemias
12.
Int J Antimicrob Agents ; 55(6): 106007, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32389720

RESUMO

A recent report identified significant reductions or disappearance of viral load in COVID-19 patients given a combination of hydroxychloroquine and azithromycin. The present communication discusses some common pharmacokinetic properties of these two drugs that may be linked to a potential underlying mechanism of action for these antiviral effects. The physicochemical properties of both hydroxychloroquine and azithromycin are consistent with particularly high affinity for the intracellular lysosomal space, which has been implicated as a target site for antiviral activity. The properties of both drugs predict dramatic accumulation in lysosomes, with calculated lysosomal drug concentrations that exceed cytosolic and extracellular concentrations by more than 50 000-fold. These predictions are consistent with previously reported experimentally measured cellular and extracellular concentrations of azithromycin. This is also reflected in the very large volumes of distribution of these drugs, which are among the highest of all drugs currently in use. The combination of hydroxychloroquine and azithromycin produces very high local concentrations in lysosomes. The clinical significance of this observation is unclear; however, the magnitude of this mechanism of drug accumulation via ion-trapping in lysosomes could be an important factor for the pharmacodynamic effects of this drug combination.


Assuntos
Azitromicina/farmacologia , Azitromicina/farmacocinética , Hidroxicloroquina/farmacologia , Hidroxicloroquina/farmacocinética , Lisossomos/efeitos dos fármacos , Antivirais/farmacocinética , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Humanos , Pandemias , Pneumonia Viral/tratamento farmacológico , Carga Viral/efeitos dos fármacos
13.
Life Sci ; 253: 117750, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32380078

RESUMO

AIM: Osteoarthritis (OA) is the main cause of disability and joint replacement surgery in the elderly. As a crucial cell survival mechanism, autophagy has been reported to decrease in OA. PHF23 is a new autophagy inhibitor which was first reported by us previously. This study aimed to explore the anti-autophagic mechanism of PHF23 to make it a possible therapeutic target of OA. MAIN METHOD: Lentiviral vectors specific to PHF23 were used on chondrocytes (C28/I2) to establish PHF23 overexpressed or knockdown stable cell strains. Interleukin (IL)-1ß (10 ng/mL) and chloroquine (CQ, 25 uM) were used as an inducer of OA and inhibitor of lysosome, respectively. Autophagy was evaluated by autophagosome formation using transmission electron microscopy (TEM) and western blot analysis of P62 and LC3B on different groups of cells. Effects of PHF23 on OA were evaluated by collagen II immunofluorescent staining and western blot analysis of OA-associated proteins MMP13 and ADAMTS5. Effects of PHF23 on AMPK and mTOR/S6K pathways and mitophagy were determined by western blot analysis. KEY FINDINGS: Knockdown of PHF23 enhanced IL-1ß-induced autophagy, while overexpression of PHF23 exerted the opposite effect. Knockdown of PHF23 protected chondrocytes against IL-1ß-induced OA by decreasing the levels of OA-associated proteins and increasing expression of Collagen II. Knockdown of PHF23 also increased mitophagy level and altered the phosphorylation levels of AMPK, mTOR, and S6K. SIGNIFICANCE: PHF23 downregulates autophagy, mitophagy in IL-1ß-induced OA-like chondrocytes and alters the activities of AMPK and mTOR/S6K, which suggests that PHF23 may be a possible therapeutic target for OA.


Assuntos
Autofagia/genética , Condrócitos/patologia , Proteínas de Homeodomínio/genética , Osteoartrite/patologia , Proteínas Quinases Ativadas por AMP/metabolismo , Sobrevivência Celular/genética , Células Cultivadas , Colágeno Tipo II/metabolismo , Técnicas de Silenciamento de Genes , Humanos , Interleucina-1beta/administração & dosagem , Lisossomos/metabolismo , Osteoartrite/genética , Proteínas Quinases S6 Ribossômicas/metabolismo , Serina-Treonina Quinases TOR/metabolismo
14.
Int J Mol Sci ; 21(9)2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32380787

RESUMO

Coronaviruses (CoVs), including Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and the novel coronavirus disease-2 (SARS-CoV-2) are a group of enveloped RNA viruses that cause a severe respiratory infection which is associated with a high mortality [...].


Assuntos
Lesão Renal Aguda/mortalidade , Lesão Renal Aguda/virologia , Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Túbulos Renais Proximais/metabolismo , Túbulos Renais Proximais/virologia , Pneumonia Viral/virologia , Lesão Renal Aguda/fisiopatologia , Lesão Renal Aguda/prevenção & controle , Angiotensina II/farmacologia , Catepsinas/metabolismo , Morte Celular/efeitos dos fármacos , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/patologia , Infecções por Coronavirus/fisiopatologia , Creatinina/sangue , Estado Terminal/mortalidade , Endossomos/efeitos dos fármacos , Endossomos/enzimologia , Endossomos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Incidência , Túbulos Renais Proximais/fisiopatologia , Lisossomos/efeitos dos fármacos , Lisossomos/enzimologia , Lisossomos/metabolismo , Pandemias , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/mortalidade , Pneumonia Viral/patologia , Pneumonia Viral/fisiopatologia , Receptores Virais/metabolismo , Síndrome Respiratória Aguda Grave/sangue , Síndrome Respiratória Aguda Grave/mortalidade , Síndrome Respiratória Aguda Grave/fisiopatologia , Internalização do Vírus , Replicação Viral
15.
Ecotoxicol Environ Saf ; 200: 110713, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32464436

RESUMO

Calcutta Leather Complex of the state of West Bengal, India has been designated as an industrially active zone with around 400 active tannery units. This area spanning 4.5 km2 is surrounded by human habitation. The soil of this region is contaminated with metal pollutants and exhibited an alteration in selected physicochemical parameters, namely cation exchange capacity, moisture content, pH, total nitrogen, total organic carbon and water holding capacity. Metaphire posthuma, a common variety of endogeic earthworm inhabiting this region is thus continuously exposed to these toxic metals. Coelomocytes, the chief immune effector cells of earthworm presented a shift in phagocytosis, lysosomal membrane stability, lysozyme and phosphatase activity, physiological apoptosis and cell cycle profile of M. posthuma sampled from the soil of tannery industry. Presence of high concentration of toxic metals and change in the physicochemical characteristics of soil led to a state of cellular stress and immunocompromisation in M. posthuma, a common inhabitant of soil of this region. Experimental endpoints bear ecotoxicological significance as biomarkers of physiological stress in earthworm for monitoring the health of soil around this tannery industrial zone.


Assuntos
Metais/toxicidade , Oligoquetos/efeitos dos fármacos , Poluentes do Solo/toxicidade , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Biomarcadores Ambientais , Humanos , Índia , Indústrias , Lisossomos/efeitos dos fármacos , Muramidase/metabolismo , Oligoquetos/enzimologia , Oligoquetos/imunologia , Oligoquetos/metabolismo , Fagocitose/efeitos dos fármacos , Solo/química
16.
Toxicol Lett ; 331: 11-21, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32439580

RESUMO

Cholestasis represents pathophysiologic syndromes defined as impaired bile flow from the liver. As an outcome, bile acids accumulate and promote hepatocyte injury, followed by liver cirrhosis and liver failure. Glycochenodeoxycholic acid (GCDCA) is relatively toxic and highly concentrated in bile and serum after cholestasis. However, the mechanism underlying GCDCA-induced hepatotoxicity remains unclear. In this study, we found that GCDCA inhibits autophagosome formation and impairs lysosomal function by inhibiting lysosomal proteolysis and increasing lysosomal pH, contributing to defects in autophagic clearance and subsequently leading to the death of L02 human hepatocyte cells. Notably, through tandem mass tag (TMT)-based quantitative proteomic analysis and database searches, 313 differentially expressed proteins were identified, of which 71 were increased and 242 were decreased in the GCDCA group compared with those in the control group. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that GCDCA suppressed the signaling pathway of transcription factor E3 (TFE3), which was the most closely associated with autophagic flux impairment. In contrast, GCDCA-inhibited lysosomal function and autophagic flux were efficiently attenuated by TFE3 overexpression. Specifically, the decreased expression of TFE3 was closely related to the disruption of reactive oxygen species (ROS) homeostasis, which could be prevented by inhibiting intracellular ROS with N-acetyl cysteine (NAC). In summary, our study is the first to demonstrate that manipulation of ROS/TFE3 signaling may be a therapeutic approach for antagonizing GCDCA-induced hepatotoxicity.


Assuntos
Autofagia/efeitos dos fármacos , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Ácido Glicoquenodesoxicólico/toxicidade , Hepatócitos/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Ácidos e Sais Biliares/metabolismo , Linhagem Celular , Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Lisossomos/efeitos dos fármacos , Proteômica
17.
FASEB J ; 34(6): 7253-7264, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32367579

RESUMO

Drug repurposing is potentially the fastest available option in the race to identify safe and efficacious drugs that can be used to prevent and/or treat COVID-19. By describing the life cycle of the newly emergent coronavirus, SARS-CoV-2, in light of emerging data on the therapeutic efficacy of various repurposed antimicrobials undergoing testing against the virus, we highlight in this review a possible mechanistic convergence between some of these tested compounds. Specifically, we propose that the lysosomotropic effects of hydroxychloroquine and several other drugs undergoing testing may be responsible for their demonstrated in vitro antiviral activities against COVID-19. Moreover, we propose that Niemann-Pick disease type C (NPC), a lysosomal storage disorder, may provide new insights into potential future therapeutic targets for SARS-CoV-2, by highlighting key established features of the disorder that together result in an "unfavorable" host cellular environment that may interfere with viral propagation. Our reasoning evolves from previous biochemical and cell biology findings related to NPC, coupled with the rapidly evolving data on COVID-19. Our overall aim is to suggest that pharmacological interventions targeting lysosomal function in general, and those particularly capable of reversibly inducing transient NPC-like cellular and biochemical phenotypes, constitute plausible mechanisms that could be used to therapeutically target COVID-19.


Assuntos
Antivirais/farmacocinética , Betacoronavirus/fisiologia , Infecções por Coronavirus/tratamento farmacológico , Reposicionamento de Medicamentos , Endossomos/virologia , Hidroxicloroquina/farmacologia , Lisossomos/virologia , Doença de Niemann-Pick Tipo C/patologia , Pneumonia Viral/tratamento farmacológico , Proteína ADAM17/fisiologia , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Alanina/análogos & derivados , Alanina/farmacologia , Alanina/uso terapêutico , Antivirais/farmacologia , Antivirais/uso terapêutico , Benzilisoquinolinas/farmacologia , Benzilisoquinolinas/uso terapêutico , Transporte Biológico , Catepsina L/fisiologia , Endocitose , Endossomos/efeitos dos fármacos , Endossomos/fisiologia , Glicopeptídeos/farmacologia , Glicopeptídeos/uso terapêutico , Humanos , Hidroxicloroquina/farmacocinética , Hidroxicloroquina/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/deficiência , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lipídeos de Membrana/metabolismo , Microdomínios da Membrana/fisiologia , Doença de Niemann-Pick Tipo C/metabolismo , Oxisteróis/metabolismo , Pandemias , Peptidil Dipeptidase A/metabolismo , Receptores Virais/metabolismo , Serina Endopeptidases/fisiologia , Triazóis/farmacologia , Triazóis/uso terapêutico , Internalização do Vírus/efeitos dos fármacos
18.
Arterioscler Thromb Vasc Biol ; 40(6): 1441-1453, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32375545

RESUMO

Megakaryocyte-derived platelets and endothelial cells store their hemostatic cargo in α- and δ-granules and Weibel-Palade bodies, respectively. These storage granules belong to the lysosome-related organelles (LROs), a heterogeneous group of organelles that are rapidly released following agonist-induced triggering of intracellular signaling pathways. Following vascular injury, endothelial Weibel-Palade bodies release their content into the vascular lumen and promote the formation of long VWF (von Willebrand factor) strings that form an adhesive platform for platelets. Binding to VWF strings as well as exposed subendothelial collagen activates platelets resulting in the release of α- and δ-granules, which are crucial events in formation of a primary hemostatic plug. Biogenesis and secretion of these LROs are pivotal for the maintenance of proper hemostasis. Several bleeding disorders have been linked to abnormal generation of LROs in megakaryocytes and endothelial cells. Recent reviews have emphasized common pathways in the biogenesis and biological properties of LROs, focusing mainly on melanosomes. Despite many similarities, LROs in platelet and endothelial cells clearly possess distinct properties that allow them to provide a highly coordinated and synergistic contribution to primary hemostasis by sequentially releasing hemostatic cargo. In this brief review, we discuss in depth the known regulators of α- and δ-granules in megakaryocytes/platelets and Weibel-Palade bodies in endothelial cells, starting from transcription factors that have been associated with granule formation to protein complexes that promote granule maturation. In addition, we provide a detailed view on the interplay between platelet and endothelial LROs in controlling hemostasis as well as their dysfunction in LRO related bleeding disorders.


Assuntos
Plaquetas/ultraestrutura , Grânulos Citoplasmáticos/fisiologia , Células Endoteliais/ultraestrutura , Hemostasia/fisiologia , Lisossomos/fisiologia , Transtornos da Coagulação Sanguínea/genética , Transtornos da Coagulação Sanguínea/fisiopatologia , Colágeno/fisiologia , Grânulos Citoplasmáticos/ultraestrutura , Humanos , Lisossomos/ultraestrutura , Corpos de Weibel-Palade/fisiologia , Corpos de Weibel-Palade/ultraestrutura , Fator de von Willebrand/metabolismo
19.
J Lipid Res ; 61(7): 972-982, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32457038

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2 has resulted in the death of more than 328,000 persons worldwide in the first 5 months of 2020. Herculean efforts to rapidly design and produce vaccines and other antiviral interventions are ongoing. However, newly evolving viral mutations, the prospect of only temporary immunity, and a long path to regulatory approval pose significant challenges and call for a common, readily available, and inexpensive treatment. Strategic drug repurposing combined with rapid testing of established molecular targets could provide a pause in disease progression. SARS-CoV-2 shares extensive structural and functional conservation with SARS-CoV-1, including engagement of the same host cell receptor (angiotensin-converting enzyme 2) localized in cholesterol-rich microdomains. These lipid-enveloped viruses encounter the endosomal/lysosomal host compartment in a critical step of infection and maturation. Niemann-Pick type C (NP-C) disease is a rare monogenic neurodegenerative disease caused by deficient efflux of lipids from the late endosome/lysosome (LE/L). The NP-C disease-causing gene (NPC1) has been strongly associated with viral infection, both as a filovirus receptor (e.g., Ebola) and through LE/L lipid trafficking. This suggests that NPC1 inhibitors or NP-C disease mimetics could serve as anti-SARS-CoV-2 agents. Fortunately, there are such clinically approved molecules that elicit antiviral activity in preclinical studies, without causing NP-C disease. Inhibition of NPC1 may impair viral SARS-CoV-2 infectivity via several lipid-dependent mechanisms, which disturb the microenvironment optimum for viral infectivity. We suggest that known mechanistic information on NPC1 could be utilized to identify existing and future drugs to treat COVID-19.


Assuntos
Anticolesterolemiantes/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Peptídeos e Proteínas de Sinalização Intracelular/genética , Doença de Niemann-Pick Tipo C/tratamento farmacológico , Pandemias , Pneumonia Viral/tratamento farmacológico , Androstenos/uso terapêutico , Betacoronavirus/metabolismo , Betacoronavirus/patogenicidade , Colesterol/metabolismo , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Reposicionamento de Medicamentos/métodos , Humanos , Hidroxicloroquina/uso terapêutico , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/virologia , Doença de Niemann-Pick Tipo C/genética , Doença de Niemann-Pick Tipo C/metabolismo , Doença de Niemann-Pick Tipo C/patologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Ligação Proteica , Receptores Virais/antagonistas & inibidores , Receptores Virais/genética , Receptores Virais/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
20.
Nature ; 581(7806): 100-105, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376951

RESUMO

Immune evasion is a major obstacle for cancer treatment. Common mechanisms of evasion include impaired antigen presentation caused by mutations or loss of heterozygosity of the major histocompatibility complex class I (MHC-I), which has been implicated in resistance to immune checkpoint blockade (ICB) therapy1-3. However, in pancreatic ductal adenocarcinoma (PDAC), which is resistant to most therapies including ICB4, mutations that cause loss of MHC-I are rarely found5 despite the frequent downregulation of MHC-I expression6-8. Here we show that, in PDAC, MHC-I molecules are selectively targeted for lysosomal degradation by an autophagy-dependent mechanism that involves the autophagy cargo receptor NBR1. PDAC cells display reduced expression of MHC-I at the cell surface and instead demonstrate predominant localization within autophagosomes and lysosomes. Notably, inhibition of autophagy restores surface levels of MHC-I and leads to improved antigen presentation, enhanced anti-tumour T cell responses and reduced tumour growth in syngeneic host mice. Accordingly, the anti-tumour effects of autophagy inhibition are reversed by depleting CD8+ T cells or reducing surface expression of MHC-I. Inhibition of autophagy, either genetically or pharmacologically with chloroquine, synergizes with dual ICB therapy (anti-PD1 and anti-CTLA4 antibodies), and leads to an enhanced anti-tumour immune response. Our findings demonstrate a role for enhanced autophagy or lysosome function in immune evasion by selective targeting of MHC-I molecules for degradation, and provide a rationale for the combination of autophagy inhibition and dual ICB therapy as a therapeutic strategy against PDAC.


Assuntos
Adenocarcinoma/imunologia , Autofagia/imunologia , Carcinoma Ductal Pancreático/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Neoplasias Pancreáticas/imunologia , Evasão Tumoral/imunologia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Apresentação do Antígeno/imunologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/imunologia , Linhagem Celular Tumoral , Cloroquina/farmacologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Masculino , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Evasão Tumoral/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA