Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
Structure ; 32(4): 400-410.e4, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38242118

RESUMEN

Giardia lamblia is a deeply branching protist and a human pathogen. Its unusual biology presents the opportunity to explore conserved and fundamental molecular mechanisms. We determined the structure of the G. lamblia 80S ribosome bound to tRNA, mRNA, and the antibiotic emetine by cryo-electron microscopy, to an overall resolution of 2.49 Å. The structure reveals rapidly evolving protein and nucleotide regions, differences in the peptide exit tunnel, and likely altered ribosome quality control pathways. Examination of translation initiation factor binding sites suggests these interactions are conserved despite a divergent initiation mechanism. Highlighting the potential of G. lamblia to resolve conserved biological principles; our structure reveals the interactions of the translation inhibitor emetine with the ribosome and mRNA, thus providing insight into the mechanism of action for this widely used antibiotic. Our work defines key questions in G. lamblia and motivates future experiments to explore the diversity of eukaryotic gene regulation.


Asunto(s)
Giardia lamblia , Humanos , Giardia lamblia/genética , Giardia lamblia/química , Giardia lamblia/metabolismo , Emetina/farmacología , Emetina/análisis , Emetina/metabolismo , Microscopía por Crioelectrón , Ribosomas/química , ARN Mensajero/metabolismo , Antibacterianos
2.
Virus Res ; 341: 199322, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38228190

RESUMEN

The emergence of highly infectious pathogens with their potential for triggering global pandemics necessitate the development of effective treatment strategies, including broad-spectrum antiviral therapies to safeguard human health. This study investigates the antiviral activity of emetine, dehydroemetine (DHE), and congeneric compounds against SARS-CoV-2 and HCoV-OC43, and evaluates their impact on the host cell. Concurrently, we assess the potential cardiotoxicity of these ipecac alkaloids. Significantly, our data reveal that emetine and the (-)-R,S isomer of 2,3-dehydroemetine (designated in this paper as DHE4) reduce viral growth at nanomolar concentrations (i.e., IC50 ∼ 50-100 nM), paralleling those required for inhibition of protein synthesis, while calcium channel blocking activity occurs at elevated concentrations (i.e., IC50 ∼ 40-60 µM). Our findings suggest that the antiviral mechanisms primarily involve disruption of host cell protein synthesis and is demonstrably stereoisomer specific. The prospect of a therapeutic window in which emetine or DHE4 inhibit viral propagation without cardiotoxicity renders these alkaloids viable candidates in strategies worthy of clinical investigation.


Asunto(s)
Alcaloides , Emetina , Emetina/análogos & derivados , Humanos , Emetina/farmacología , Ipeca/farmacología , Cardiotoxicidad , Antivirales/toxicidad
3.
J Inflamm Res ; 16: 6139-6153, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38107383

RESUMEN

Background: Diabetic nephropathy (DN) is one of the primary causes of end-stage renal disease, yet effective therapeutic targets remain elusive. This study aims to identify novel diagnostic biomarkers and potential therapeutic candidates for DN. Methods: Differentially expressed genes (DEGs) in GSE96804 and GSE142025 were identified and functional enrichment analysis was performed. Diagnostic biomarkers were selected using machine learning algorithms and evaluated by Receiver Operating Characteristic analysis. c-Fos expression was validated in an established DN mouse model. Immune infiltration levels were assessed with Single-Sample Gene Set Enrichment Analysis. Co-expression analysis revealed regulatory relationships involving FOS. cMAP predicted potential therapeutic candidates. Transcriptome sequencing and experiments in RAW264.7 cells was performed to investigate molecular mechanisms of emetine. Results: In both datasets, we identified 44 upregulated and 74 downregulated DEGs involved in focal adhesion, ECM-receptor interaction, and the PI3K-Akt signaling pathway. FOS emerged as a robust diagnostic marker with decreased expression in DN patients and DN mouse. Co-expression analysis revealed potential regulatory mechanisms of FOS, implicating the MAPK signaling pathway, regulation of cell proliferation and apoptotic signaling pathways. Immune dysregulation was observed in DN patients. Notably, emetine was identified as a potential therapeutic candidate. Transcriptome sequencing and experimental validation demonstrated emetine suppressed M1 macrophage polarization by inhibiting the activation of NF-κB signaling pathway, as well as reducing the expression of Il-18 and Ccl5. Conclusion: In conclusion, our study identified FOS as a promising diagnostic biomarker and emetine as a potential therapeutic candidate for DN. These findings enhance our understanding of DN pathogenesis and present novel prospects for therapeutic strategies.

4.
J Cell Mol Med ; 27(23): 3839-3850, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37723905

RESUMEN

Radiation-induced lung injury (RILI), divided into early radiation pneumonia (RP) and late radiation-induced pulmonary fibrosis (RIPF), is a common serious disease after clinical chest radiotherapy or nuclear accident, which seriously threatens the life safety of patients. There has been no effective prevention or treatment strategy till now. Epithelial-mesenchymal transition (EMT) is a key step in the occurrence and development of RILI. In this study, we demonstrated that emetine dihydrochloride (EDD) alleviated RILI through inhibiting EMT. We found that EDD significantly attenuated EMT-related markers, reduced Smad3 phosphorylation expression after radiation. Then, for the first time, we observed EDD alleviated lung hyperaemia and reduced collagen deposit induced by irradiation, providing protection against RILI. Finally, it was found that EDD inhibited radiation-induced EMT in lung tissues. Our study suggested that EDD alleviated RILI through inhibiting EMT by blocking Smad3 signalling pathways. In summary, our results indicated that EDD is a novel potential radioprotector for RILI.


Asunto(s)
Lesión Pulmonar , Fibrosis Pulmonar , Traumatismos por Radiación , Humanos , Lesión Pulmonar/tratamiento farmacológico , Lesión Pulmonar/etiología , Lesión Pulmonar/metabolismo , Emetina/farmacología , Pulmón/patología , Traumatismos por Radiación/metabolismo , Fibrosis Pulmonar/tratamiento farmacológico , Fibrosis Pulmonar/etiología , Fibrosis Pulmonar/metabolismo , Transición Epitelial-Mesenquimal
5.
Physiol Behav ; 269: 114278, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37352906

RESUMEN

No prior studies have shown that gaping reactions are produced with the avoidance of conditioned taste caused by cisplatin and emetine. Therefore, we tried to demonstrate it using a taste reactivity test in rats and found the gaping reactions induced when saccharin is readministered after gustatory conditioning that paired saccharin with cisplatin or emetine. Since conditioned gaping reactions indicate the aversion to saccharin taste and conditioned nausea, the present study suggest that the taste aversion is induced by cisplatin and emetine. It was also found that with intraperitoneal injections of emetine alone, gaping almost never occurs.


Asunto(s)
Cisplatino , Emetina , Ratas , Animales , Emetina/efectos adversos , Cisplatino/toxicidad , Sacarina/farmacología , Gusto , Cloruro de Litio/farmacología , Náusea/inducido químicamente , Reacción de Prevención
6.
Phytother Res ; 37(5): 2168-2186, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37039761

RESUMEN

In the search for compounds that inhibit the SARS-CoV-2 after the onset of the COVID-19 pandemic, isoquinoline-containing alkaloids have been identified as compounds with high potential to fight the disease. In addition to having strong antiviral activities, most of these alkaloids have significant anti-inflammatory effects which are often manifested through the inhibition of a promising host-based anti-COVID-19 target, the p38 MAPK signaling pathway. In the present review, our pharmacological and medicinal chemistry evaluation resulted in highlighting the potential of anti-SARS-CoV-2 isoquinoline-based alkaloids for the treatment of COVID-19 patients. Considering critical parameters of the antiviral and anti-inflammatory activities, mechanism of action, as well as toxicity/safety profile, we introduce the alkaloids emetine, cephaeline, and papaverine as high-potential therapeutic agents for use in the treatment of COVID-19. Although preclinical studies confirm that some isoquinoline-based alkaloids reviewed in this study have a high potential to inhibit the SARS-CoV-2, their entry into drug regimens of COVID-19 patients requires further clinical trial studies and toxicity evaluation.


Asunto(s)
Alcaloides , COVID-19 , Humanos , Química Farmacéutica , SARS-CoV-2 , Pandemias , Isoquinolinas/farmacología , Isoquinolinas/uso terapéutico , Alcaloides/farmacología , Alcaloides/uso terapéutico , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Antivirales/farmacología , Antivirales/uso terapéutico
7.
Cancer Chemother Pharmacol ; 91(4): 303-315, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36941385

RESUMEN

BACKGROUND: Gastric cancer (GC) is a life-threatening malignant tumor with high incidence rate. Despite great progress, there are still many GC sufferers that cannot benefit from the existing anti-GC treatments. Therefore, it is still necessary to develop novel medicines against GC. Emetine, a natural small molecule isolated from Psychotria ipecacuanha, has been broadly used for medicinal purposes including cancer treatment. Here, we conducted a comprehensive study on the anti-GC effects of emetine and the related mechanisms of action. METHODS: The cell viability was evaluated by MTT and colony formation assay. Cellular proliferation and apoptosis were analyzed by edu incorporation assay and Annexin V-PI staining, respectively. Moreover, wound healing assay and transwell invasion assay were conducted to detect cell migration and invasion after treatment with emetine. To elucidate the molecular mechanism involved in the anti-GC effects of emetine, RNA sequencing and functional enrichment analysis were carried out on MGC803 cells. Then, the western blot analysis was performed to further verify the anti-GC mechanism of emetine. In vivo anti-tumor efficacy of emetine was evaluated in the MGC803 xenograft model. RESULTS: MTT and colony formation assay exhibited a strong potency of emetine against GC cell growth, with IC50 values of 0.0497 µM and 0.0244 µM on MGC803 and HGC-27 cells, respectively. Further pharmacodynamic studies revealed that emetine restrained the growth of GC cells mainly via proliferation inhibition and apoptosis induction. Meanwhile, emetine also had the ability to block GC cell migration and invasion. The results of RNA sequencing and western blot showed that emetine acted through regulating multiple signaling pathways, including not only MAPKs and Wnt/ß-catenin signaling axes, but also PI3K/AKT and Hippo/YAP signaling cascades that were not found in other tumor types. Notably, the antitumor efficacy of emetine could also be observed in MGC803 xenograft models. CONCLUSION: Our data demonstrate that emetine is a promising lead compound and even a potential drug candidate for GC treatment, deserving further structural optimization and development.


Asunto(s)
Emetina , Neoplasias Gástricas , Humanos , Emetina/farmacología , Emetina/uso terapéutico , Fosfatidilinositol 3-Quinasas/metabolismo , Neoplasias Gástricas/metabolismo , Proliferación Celular , Vía de Señalización Wnt , Línea Celular Tumoral , Movimiento Celular , Apoptosis
8.
Biosci Biotechnol Biochem ; 87(5): 501-510, 2023 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-36809780

RESUMEN

TEAD is a transcription factor responsible for the output of the tumor suppressor Hippo pathway. The transcriptional activity of TEAD requires molecular interaction with its transcriptional coactivator, YAP. Aberrant activation of TEAD is deeply involved in tumorigenesis and is associated with poor prognosis, suggesting that inhibitors targeting the YAP-TEAD system are promising as antitumor agents. In this study, we identified NPD689, an analog of the natural product alkaloid emetine, as an inhibitor of the YAP-TEAD interaction. NPD689 suppressed the transcriptional activity of TEAD and reduced the viability of human malignant pleural mesothelioma and non-small cell lung cancer cells but not the viability of normal human mesothelial cells. Our results suggest that NPD689 is not only a new useful chemical tool for elucidating the biological role of the YAP-TEAD system but also has potential as a starting compound for developing a cancer therapeutic agent that targets the YAP-TEAD interaction.


Asunto(s)
Antineoplásicos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antineoplásicos/farmacología , Emetina , Neoplasias Pulmonares/patología , Factores de Transcripción/metabolismo , Proteínas Señalizadoras YAP , Factores de Transcripción de Dominio TEA/metabolismo
9.
Cells ; 11(18)2022 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-36139404

RESUMEN

Chloroquine and Emetine are drugs used to treat human parasitic infections. In addition, it has been shown that these drugs have an antiviral effect. Both drugs were also found to cause a suppressive effect on the growth of cancer cells of different origins. Here, using the replication-deficient HIV-1-based lentiviral vector particles, we evaluated the ability of the combination of these drugs to reduce viral transduction efficiency. We showed that these drugs act synergistically to decrease cancer cell growth when added in combination with medium containing lentiviral particles. We found that the combination of these drugs with lentiviral particles decreases the viability of treated cells. Taken together, we state the oncolytic potential of the medium containing HIV-1-based particles provoked by the combination of Chloroquine and Emetine.


Asunto(s)
VIH-1 , Antivirales , Cloroquina/farmacología , Emetina/farmacología , Humanos
10.
Cell Cycle ; 21(22): 2379-2386, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35852390

RESUMEN

Emetine is one of the most highly potent anti-SARS-CoV-2 agents ever identified. In addition to having strong anti-SARS-CoV-2 activities, emetine has other valuable therapeutic effects such as strong anti-inflammatory and anti-arterial pulmonary hypertension (APH) properties, which are suitable for the treatment of COVID-19. Its proper concomitant therapeutic effect has led researchers to test this compound in clinical trials to combat COVID-19. However, due to the risks of cardiac complications, very low doses of emetine have been used in different studies, which may not have significant therapeutic effects. The p38 MAPK signaling pathway is strongly highlighted as an important operator in cardiac cellular damages such as disruption of cardiac fibroblast function and myopathy/cardiomyopathy. Inhibition of this pathway by appropriate inhibitors has also been considered by scientists as a promising strategy for the treatment of fatal host-related hyper-inflammatory immune responses following SARS-CoV-2 infection. Although remarkable stimulatory effects of emetine on activation of the p38 MAPK pathway have been reported in recent studies and strong evidence suggests that this pathway plays an effective role in the emetine's toxicities, it has not been discussed yet that emetine induced cellular cardiac complications may be due to the activation of this critical pathway. Considering these points could lead to the finding of strategies for applying the valuable potential of emetine in the treatment of COVID-19 at low risks.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Emetina , Humanos , Emetina/farmacología , SARS-CoV-2 , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
11.
BMC Cancer ; 22(1): 687, 2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35733175

RESUMEN

BACKGROUND: Patients with lung adenocarcinoma (LUAD) may be more predisposed to coronavirus disease 2019 (COVID-19) and have a poorer prognosis. Currently, there is still a lack of effective anti-LUAD/COVID-19 drugs. Thus, this study aimed to screen for an effective anti-LUAD/COVID-19 drug and explore the potential mechanisms. METHODS: Firstly, we performed differentially expressed gene (DEG) analysis on LUAD transcriptome profiling data in The Cancer Genome Atlas (TCGA), where intersections with COVID-19-related genes were screened out. Then, we conducted Cox proportional hazards analyses on these LUAD/COVID-19 DEGs to construct a risk score. Next, LUAD/COVID-19 DEGs were uploaded on Connectivity Map to obtain drugs for anti-LUAD/COVID-19. Finally, we used network pharmacology, molecular docking, and molecular dynamics (MD) simulation to explore the drug's therapeutic targets and potential mechanisms for anti-LUAD/COVID-19. RESULTS: We identified 230 LUAD/COVID-19 DEGs and constructed a risk score containing 7 genes (BTK, CCL20, FURIN, LDHA, TRPA1, ZIC5, and SDK1) that could classify LUAD patients into two risk groups. Then, we screened emetine as an effective drug for anti-LUAD/COVID-19. Network pharmacology analyses identified 6 potential targets (IL6, DPP4, MIF, PRF1, SERPING1, and SLC6A4) for emetine in anti-LUAD/COVID-19. Molecular docking and MD simulation analyses showed that emetine exhibited excellent binding capacities to DDP4 and the main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). CONCLUSIONS: This study found that emetine may inhibit the entry and replication of SARS-CoV-2 and enhance tumor immunity by bounding to DDP4 and Mpro.


Asunto(s)
Adenocarcinoma del Pulmón , Tratamiento Farmacológico de COVID-19 , Emetina , Neoplasias Pulmonares , SARS-CoV-2 , Adenocarcinoma del Pulmón/complicaciones , Adenocarcinoma del Pulmón/tratamiento farmacológico , Biología Computacional , Proteínas de Unión al ADN/genética , Emetina/farmacología , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/tratamiento farmacológico , Simulación del Acoplamiento Molecular , SARS-CoV-2/efectos de los fármacos , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Proteínas de Transporte de Serotonina en la Membrana Plasmática/metabolismo , Factores de Transcripción/genética
12.
Cancers (Basel) ; 14(10)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35626133

RESUMEN

The lack of effective therapies remains one of the main challenges for malignant pleural mesothelioma (MPM). In this perspective, drug repositioning could accelerate the identification of novel treatments. We screened 1170 FDA-approved drugs on a SV40-immortalized mesothelial (MeT-5A) and five MPM (Mero-14, Mero-25, IST-Mes2, NCI-H28 and MSTO-211H) cell lines. Biological assays were carried out for 41 drugs, showing the highest cytotoxicity and for whom there were a complete lack of published literature in MPM. Cytotoxicity and caspase activation were evaluated with commercially available kits and cell proliferation was assayed using MTT assay and by clonogenic activity with standard protocols. Moreover, the five most effective drugs were further evaluated on patient-derived primary MPM cell lines. The most active molecules were cephalomannine, ouabain, alexidine, thonzonium bromide, and emetine. Except for alexidine, these drugs inhibited the clonogenic ability and caspase activation in all cancer lines tested. The proliferation was inhibited also on an extended panel of cell lines, including primary MPM cells. Thus, we suggest that cephalomannine, ouabain, thonzonium bromide, and emetine could represent novel candidates to be repurposed for improving the arsenal of therapeutic weapons in the fight against MPM.

13.
J Biomol Struct Dyn ; 40(20): 10122-10135, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34254564

RESUMEN

The main objective of this study is to find out the anti-SARS-CoV-2 potential of emetine by using molecular docking and dynamic simulation approaches. Interestingly, molecular docking studies suggest that Emetine showed significant binding affinity toward Nsp15 (-10.8 kcal/mol) followed by Nsp12 (-9.5 kcal/mol), RNA-dependent RNA polymerase, RdRp (-9.5 kcal/mol), Nsp16 (-9.4 kcal/mol), Nsp10 (-9.2 kcal/mol), Papain-like protein (-9.0 kcal/mol), Nsp13 (-9.0 kcal/mol), Nsp14 (-8.9 kcal/mol) and Spike Protein Receptor Domain (-8.8 kcal/mol) and chymotrypsin-like protease, 3CLpro (-8.5 kcal/mol), respectively, which are essential for viral infection and replication. In addition, molecular dynamic simulation (MD) was also performed for 140 ns to explore the stability behavior of the main targets and inhibitor complexes as well as the binding mechanics of the ligand to the target proteins. The obtained MD results followed by absolute binding energy calculation confirm that the binding of emetine at the level of the various receptors is more stable. The complex EmetineNSP15, mechanistically was stabilized as follows: Emetine first binds to the monomer, after, binds to the second inducing the formation of a dimer which in turn leading to the formation of complex that simulation stabilizes it at a value less than 5 Å. Overall, supported by the powerful and good pharmacokinetic data of Emetine, our findings with clinical trials may be helpful to confirm that Emetine could be promoted in the prevention and eradication of COVID-19 by reducing the severity in the infected persons and therefore can open possible new strategies for drug repositioning. Communicated by Ramaswamy H. Sarma.


Asunto(s)
Proteasas Similares a la Papaína de Coronavirus , Emetina , Inhibidores de Proteasas , SARS-CoV-2 , Emetina/farmacología , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Papaína , Inhibidores de Proteasas/farmacología , SARS-CoV-2/efectos de los fármacos , Antivirales/farmacología , Proteasas Similares a la Papaína de Coronavirus/antagonistas & inhibidores
14.
J Biochem Mol Toxicol ; 35(10): e22868, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34338395

RESUMEN

Osteosarcoma (OS) is a primary bone neoplasm that is highly malignant. As advances in chemotherapy for the treatment of OS have stagnated, discovery of new reagents is required. Emetine is a phytochemical which can be isolated from a medicinal herb Cephaelis ipecacuanha and is traditionally used for amoebicides. Previous studies have demonstrated that emetine can possibly be repositioned for use in anticancer reagents. However, any anticancer effects and underlying mechanisms of emetine on human OS are not yet well understood. In this study, we analyzed the anticancer effects and involved cellular mechanisms after treatment with emetine to U2OS human OS cells. Emetine significantly reduced both the viability and proliferation, and induced apoptosis via activation of caspase-3 and caspase-7 in U2OS cells. Emetine effectively inhibited the migration and invasion of U2OS cells. Gelatinase activities of matrix metalloproteinase 2 (MMP-2) and MMP-9 were reduced by emetine. MMP-9 was transcriptionally inhibited, while MMP-2 was posttranscriptionally repressed, via the reduced expression of membrane-type I-matrix metalloproteinase (MT1-MMP). p38, which is closely related with induction of apoptosis, was stimulated by emetine. Extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and ß-catenin, which are linked with expression of MMPs, were downregulated. Emetine exerted anticancer effects on MG63 human OS cells as well. Taken together, our study demonstrated the anticancer and antimetastatic potential of emetine in treating human OS for the first time. It is expected that emetine may be a promising drug candidate to be repositioned for chemotherapy of OS.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Óseas/metabolismo , Cephaelis/química , Emetina/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Osteosarcoma/metabolismo , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , beta Catenina/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Apoptosis/efectos de los fármacos , Neoplasias Óseas/patología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Regulación hacia Abajo , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Osteosarcoma/patología
15.
Physiol Behav ; 241: 113565, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34461130

RESUMEN

We investigated the effect of area postrema lesions and selective vagotomy of afferent fibers on emetine-induced nausea in rats. We evaluated the acquisition of the conditioned taste avoidance (CTA) to 0.1% saccharin solution after conditioning with emetine dihydrochloride (5.54 mg/kg, i.p., 1% BW). The CTA was measured in three groups of rats: a bilateral subdiaphragmatic afferent vagotomy group, an area postrema lesion group, and a sham lesion group. The bilateral vagotomy and sham groups of rats showed acquisition of CTA within 2 days of the test date. Taste avoidance was never conditioned in the area postrema lesion group. These results indicate that the area postrema plays a crucial role in the induction of emetine-induced nausea.


Asunto(s)
Área Postrema , Gusto , Animales , Reacción de Prevención , Emetina , Ratas , Vagotomía
16.
Parasitol Int ; 85: 102437, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34389492

RESUMEN

Babesia gibsoni is a tick-transmitted intraerythrocytic apicomplexan parasite that causes babesiosis in dogs. Due to the strong side effects and lack of efficacy of current drugs, novel drugs against B. gibsoni are urgently needed. Natural products as a source for new drugs is a good choice for screening drugs against B. gibsoni. The current study focuses on identifying novel potential drugs from natural products against B. gibsoniin vitro. Parasite inhibition was verified using a SYBR green I-based fluorescence assay. A total of 502 natural product compounds were screened for anti-B. gibsoni activity in vitro. Twenty-four compounds showed high growth inhibition (>80%) on B. gibsoni and 5 plant-derived compounds were selected for further study. The half-maximal inhibitory concentration (IC50) values of lycorine (LY), vincristine sulfate (VS), emetine·2HCl (EME), harringtonine (HT) and cephaeline·HBr (CEP) were 784.4 ± 3.3, 643.0 ± 2.8, 253.1 ± 1.4, 23.4 ± 1.2, and 108.1 ± 4.3 nM, respectively. The Madin-Darby canine kidney (MDCK) cell line was used to assess cytotoxicity of hit compounds. All compounds showed minimal toxicity to the MDCK cells. The effects of hit compounds combined with diminazene aceturate (DA) on B. gibsoni were further evaluated in vitro. VS, EME, HT or CEP combined with DA showed synergistic effects against B. gibsoni, whereas LY combined with DA showed an antagonistic effect against B. gibsoni. The results obtained in this study indicate that LY, VS, EME, HT and CEP are promising compounds for B. gibsoni treatment.


Asunto(s)
Antiprotozoarios/farmacología , Babesia/efectos de los fármacos , Productos Biológicos/farmacología , Diminazeno/análogos & derivados , Animales , Babesiosis/parasitología , Babesiosis/prevención & control , Diminazeno/farmacología , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/prevención & control , Perros , Evaluación Preclínica de Medicamentos , Concentración 50 Inhibidora
17.
J BioX Res ; 4(2): 53-59, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34254034

RESUMEN

OBJECTIVE: Emetine, an isoquinoline alkaloid that is enriched at high concentrations in the lung, has shown potent in vitro activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The aim of this study was to better understand the effectiveness of low-dose emetine for patients with coronavirus disease 2019 (COVID-19). METHODS: In this real-world study, 63 patients with mild or common COVID-19 were recruited from Wuhan Fangcang Shelter Hospital and five COVID-19-designated hospitals in Anhui Province, China from February to March 2020. Thirty-nine patients from Wuhan Fangcang Shelter Hospital were assigned to a pragmatic randomized controlled clinical trial, and 24 patients from the 5 COVID-19-designated hospitals in Anhui Province underwent a real-world study. The medication course of emetine was less than 10 days. The main symptoms and adverse reactions of all patients were observed and recorded. The primary outcome measure was the time required for a negative SARS-CoV-2 RNA result or the negative result rate on day 10. Secondary outcomes included axillary temperature, transcutaneous oxygen saturation, and respiratory frequency recovery. The study was approved by the Ethics Committee of The First Affiliated Hospital of Anhui Medical University on February 20, 2019 (approval No. PJ2020-03-19) and was registered with the Chinese Clinical Trial Registry on February 20, 2019 (registration number: ChiCTR2000030022). RESULTS: The oxygen saturation values were higher in the treatment group than in the control group on the first day after enrollment for patients treated at Fangcang Shelter Hospital. The axillary body temperature, respiratory rate, and oxygen saturation among patients in Fangcang Shelter Hospital were related to the time effect but not to the intervention measures. The respiratory rate and oxygen saturation of patients in the Anhui designated hospitals were related to the intervention measures but not to the time effect. The axillary body temperature of patients in Anhui designated hospitals was related to the time effect but not to the intervention measures. CONCLUSION: Our preliminary study shows that low-dose emetine combined with basic conventional antiviral drugs improves clinical symptoms in patients with mild and common COVID-19 without apparent adverse effects, suggesting that moderately increased doses of emetine may have good potential for treatment and prevention of COVID-19.

18.
Life Sci ; 280: 119752, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34171382

RESUMEN

AIMS: Angiotensin-converting enzyme 2 (ACE2) is a key negative regulator of the renin-angiotensin system and also a major receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Here, we reveal a role for NF-κB in human lung cell expression of ACE2, and we further explore the potential utility of repurposing NF-κB inhibitors to downregulate ACE2. MAIN METHODS: Expression of ACE2 was assessed by Western blotting and RT-qPCR in multiple human lung cell lines with or without NF-κB inhibitor treatment. Surface ACE2 expression and intracellular reactive oxygen species (ROS) levels were measured with flow cytometry. p50 was knocked down with siRNA. Cytotoxicity was monitored by PARP cleavage and MTS assay. KEY FINDINGS: Pyrrolidine dithiocarbamate (PDTC), an NF-κB inhibitor, suppressed endogenous ACE2 mRNA and protein expression in H322M and Calu-3 cells. The ROS level in H322M cells was increased after PDTC treatment, and pretreatment with N-acetyl-cysteine (NAC) reversed PDTC-induced ACE2 suppression. Meanwhile, treatment with hydrogen peroxide augmented ACE2 suppression in H322M cells with p50 knockdown. Two repurposed NF-κB inhibitors, the anthelmintic drug triclabendazole and the antiprotozoal drug emetine, also reduced ACE2 mRNA and protein levels. Moreover, zinc supplementation augmented the suppressive effects of triclabendazole and emetine on ACE2 expression in H322M and Calu-3 cells. SIGNIFICANCE: These results suggest that ACE2 expression is modulated by ROS and NF-κB signaling in human lung cells, and the combination of zinc with triclabendazole or emetine shows promise for clinical treatment of ACE2-related disease.


Asunto(s)
Enzima Convertidora de Angiotensina 2/genética , Antiparasitarios/farmacología , Regulación hacia Abajo/efectos de los fármacos , Emetina/farmacología , FN-kappa B/antagonistas & inhibidores , Triclabendazol/farmacología , Zinc/farmacología , COVID-19/genética , Línea Celular , Reposicionamiento de Medicamentos , Humanos , Pulmón/citología , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Pirrolidinas/farmacología , Tiocarbamatos/farmacología , Tratamiento Farmacológico de COVID-19
19.
Viruses ; 13(4)2021 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-33918368

RESUMEN

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes COVID-19 and is responsible for the ongoing pandemic. Screening of potential antiviral drugs against SARS-CoV-2 depend on in vitro experiments, which are based on the quantification of the virus titer. Here, we used virus-induced cytopathic effects (CPE) in brightfield microscopy of SARS-CoV-2-infected monolayers to quantify the virus titer. Images were classified using deep transfer learning (DTL) that fine-tune the last layers of a pre-trained Resnet18 (ImageNet). To exclude toxic concentrations of potential drugs, the network was expanded to include a toxic score (TOX) that detected cell death (CPETOXnet). With this analytic tool, the inhibitory effects of chloroquine, hydroxychloroquine, remdesivir, and emetine were validated. Taken together we developed a simple method and provided open access implementation to quantify SARS-CoV-2 titers and drug toxicity in experimental settings, which may be adaptable to assays with other viruses. The quantification of virus titers from brightfield images could accelerate the experimental approach for antiviral testing.


Asunto(s)
Antivirales/farmacología , Aprendizaje Profundo , Evaluación Preclínica de Medicamentos/métodos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Aprendizaje Automático , SARS-CoV-2/efectos de los fármacos , Adenosina Monofosfato/análogos & derivados , Adenosina Monofosfato/farmacología , Alanina/análogos & derivados , Animales , COVID-19 , Chlorocebus aethiops , Proteínas de la Nucleocápside de Coronavirus , Fosfoproteínas , Células Vero , Carga Viral/efectos de los fármacos
20.
Antiviral Res ; 189: 105056, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33711336

RESUMEN

Emetine is a FDA-approved drug for the treatment of amebiasis. Previously we demonstrated the antiviral efficacy of emetine against some RNA and DNA viruses. In this study, we evaluated the in vitro antiviral efficacy of emetine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and found it to be a low nanomolar (nM) inhibitor. Interestingly, emetine exhibited protective efficacy against lethal challenge with infectious bronchitis virus (IBV; a chicken coronavirus) in the embryonated chicken egg infection model. Emetine treatment led to a decrease in viral RNA and protein synthesis without affecting other steps of viral life cycle such as attachment, entry and budding. In a chromatin immunoprecipitation (CHIP) assay, emetine was shown to disrupt the binding of SARS-CoV-2 mRNA with eIF4E (eukaryotic translation initiation factor 4E, a cellular cap-binding protein required for initiation of protein translation). Further, molecular docking and molecular dynamics simulation studies suggested that emetine may bind to the cap-binding pocket of eIF4E, in a similar conformation as m7-GTP binds. Additionally, SARS-CoV-2 was shown to exploit ERK/MNK1/eIF4E signalling pathway for its effective replication in the target cells. Collectively our results suggest that further detailed evaluation of emetine as a potential treatment for COVID-19 may be warranted.


Asunto(s)
Antivirales , Emetina , Virus de la Bronquitis Infecciosa/efectos de los fármacos , ARN Viral/metabolismo , SARS-CoV-2/efectos de los fármacos , Animales , Antivirales/farmacología , Antivirales/uso terapéutico , Embrión de Pollo , Chlorocebus aethiops , Infecciones por Coronavirus/tratamiento farmacológico , Emetina/farmacología , Emetina/uso terapéutico , Factor 4E Eucariótico de Iniciación/metabolismo , Unión Proteica/efectos de los fármacos , ARN Mensajero/metabolismo , Transducción de Señal , Células Vero
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA