RESUMEN
The flavonoid naringenin (Nar), present in citrus fruits and tomatoes, has been identified as a blocker of an emerging class of human intracellular channels, namely the two-pore channel (TPC) family, whose role has been established in several diseases. Indeed, Nar was shown to be effective against neoangiogenesis, a process essential for solid tumor progression, by specifically impairing TPC activity. The goal of the present review is to illustrate the rationale that links TPC channels to the mechanism of coronavirus infection, and how their inhibition by Nar could be an efficient pharmacological strategy to fight the current pandemic plague COVID-19.
Asunto(s)
Tratamiento Farmacológico de COVID-19 , Bloqueadores de los Canales de Calcio/farmacología , Canales de Calcio/metabolismo , Flavanonas/farmacología , Neoplasias/tratamiento farmacológico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico , Arabidopsis/metabolismo , COVID-19/epidemiología , COVID-19/patología , COVID-19/virología , Bloqueadores de los Canales de Calcio/uso terapéutico , Evaluación Preclínica de Medicamentos , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Endosomas/virología , Flavanonas/uso terapéutico , Humanos , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Lisosomas/virología , Neoplasias/irrigación sanguínea , Neoplasias/patología , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/patología , Pandemias/prevención & control , SARS-CoV-2/patogenicidad , Vacuolas/metabolismo , Internalización del Virus/efectos de los fármacosRESUMEN
Increasing evidences reveal that autophagy inhibitor could enhance the effect of chemotherapy to cancer. However, few autophagy inhibitors are currently approved for clinical application in humans. Berbamine (BBM) is a natural compound extracted from traditional Chinese medicine that is widely used for treatment of a variety of diseases without any obvious side effects. Here we found that BBM is a novel auophagy inhibitor, which potently induced the accumulation of autophagosomes by inhibiting autophagosome-lysosome fusion in human breast cancer cells. Mechanistically, we found that BBM blocked autophagosome-lysosome fusion by inhibiting the interaction of SNAP29 and VAMP8. Furthermore, BBM induced upregulation of BNIP3 and the interaction between SNAP29 and BNIP3. BNIP3 depletion or SNAP29 overexpression abrogated BBM-mediated blockade of autophagosome-lysosome fusion through the interaction between SNAP29 and VAMP8, whereas BNIP3 overexpression blocked autophagosome-lysosome fusion through inhibition of the interaction between SNAP29 and VAMP8. These findings suggest that upregulation of BNIP3 and interaction between BNIP3 and SNAP29 could be involved in BBM-mediated blockade of autophagosome-lysosome fusion through inhibition of the interaction between SNAP29 and VAMP8. Our findings identify the critical role of BNIP3 in blockade of autophagosome-lysosome fusion mediated by BBM, and suggest that BBM could potentially be further developed as a novel autophagy inhibitor, which could enhance the effect of chemotherapy to cancer.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Autofagia/efectos de los fármacos , Bencilisoquinolinas/farmacología , Proteínas de la Membrana/genética , Proteínas Proto-Oncogénicas/genética , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/genética , Proteínas R-SNARE/genética , Células A549 , Autofagosomas/metabolismo , Autofagosomas/virología , Autofagia/genética , Línea Celular Tumoral , Regulación de la Expresión Génica , Humanos , Lisosomas/metabolismo , Lisosomas/virología , Células MCF-7 , Fusión de Membrana/efectos de los fármacos , Proteínas de la Membrana/agonistas , Proteínas de la Membrana/metabolismo , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Proteínas Proto-Oncogénicas/agonistas , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , Proteínas R-SNARE/metabolismo , Proteína Sequestosoma-1/genética , Proteína Sequestosoma-1/metabolismo , Transducción de SeñalRESUMEN
Our previous study demonstrated that Melaleuca alternifolia (tea tree) oil (TTO) had an interesting antiviral activity against Influenza A in MDCK cells. In fact, when we tested TTO and some of its components, we found that TTO had an inhibitory effect on influenza virus replication at doses below the cytotoxic dose; terpinen-4-ol, terpinolene, and alfa-terpineol were the main active components. The aim of this study was to investigate the mechanism of action of TTO and its active components against Influenza A/PR/8 virus subtype H1N1 in MDCK cells. None of the test compounds showed virucidal activity nor any protective action for the MDCK cells. Thus, the effect of TTO and its active components on different steps of the replicative cycle of influenza virus was studied by adding the test compounds at various times after infection. These experiments revealed that viral replication was significantly inhibited if TTO was added within 2h of infection, indicating an interference with an early step of the viral replicative cycle of influenza virus. The influence of the compound on the virus adsorption step, studied by the infective center assay, indicated that TTO did not interfere with cellular attachment of the virus. TTO did not inhibit influenza virus neuraminidase activity, as shown by the experiment measuring the amount of 4-methylumbelliferone, cleaved by the influenza virus neuraminidase from the fluorogenic substrate 2'-O-(4-methylumbelliferyl)-N-acetylneuraminic acid. The effect of TTO on acidification of cellular lysosomes was studied by vital staining with acridine orange using bafilomycin A1 as positive control. The treatment of cells with 0.01% (v/v) of TTO at 37°C for 4h before staining inhibited the acridine orange accumulation in acid cytoplasmic vesicles, indicating that TTO could inhibit viral uncoating by an interference with acidification of intralysosomal compartment.