scholarly journals Tomatidine reduces Chikungunya virus progeny release by controlling viral protein expression

2021 ◽  
Vol 15 (11) ◽  
pp. e0009916
Author(s):  
Berit Troost-Kind ◽  
Martijn J. van Hemert ◽  
Denise van de Pol ◽  
Heidi van der Ende-Metselaar ◽  
Andres Merits ◽  
...  
Keyword(s):  
Protein Expression ◽  
Viral Protein ◽  
Chikungunya Virus ◽  
Antiviral Treatment ◽  
Antiviral Effect ◽  
Virus Infectivity ◽  
Expression Levels ◽  
Viral Protein Expression ◽  
Huh7 Cells

Tomatidine, a natural steroidal alkaloid from unripe green tomatoes has been shown to exhibit many health benefits. We recently provided in vitro evidence that tomatidine reduces the infectivity of Dengue virus (DENV) and Chikungunya virus (CHIKV), two medically important arthropod-borne human infections for which no treatment options are available. We observed a potent antiviral effect with EC50 values of 0.82 μM for DENV-2 and 1.3 μM for CHIKV-LR. In this study, we investigated how tomatidine controls CHIKV infectivity. Using mass spectrometry, we identified that tomatidine induces the expression of p62, CD98, metallothionein and thioredoxin-related transmembrane protein 2 in Huh7 cells. The hits p62 and CD98 were validated, yet subsequent analysis revealed that they are not responsible for the observed antiviral effect. In parallel, we sought to identify at which step of the virus replication cycle tomatidine controls virus infectivity. A strong antiviral effect was seen when in vitro transcribed CHIKV RNA was transfected into Huh7 cells treated with tomatidine, thereby excluding a role for tomatidine during CHIKV cell entry. Subsequent determination of the number of intracellular viral RNA copies and viral protein expression levels during natural infection revealed that tomatidine reduces the RNA copy number and viral protein expression levels in infected cells. Once cells are infected, tomatidine is not able to interfere with active RNA replication yet it can reduce viral protein expression. Collectively, the results delineate that tomatidine controls viral protein expression to exert its antiviral activity. Lastly, sequential passaging of CHIKV in presence of tomatidine did not lead to viral resistance. Collectively, these results further emphasize the potential of tomatidine as an antiviral treatment towards CHIKV infection.

scholarly journals Inhibition of Chikungunya Virus Replication by Harringtonine, a Novel Antiviral That Suppresses Viral Protein Expression

2012 ◽  
Vol 57 (1) ◽  
pp. 155-167 ◽  
Author(s):  
Parveen Kaur ◽  
Meerra Thiruchelvan ◽  
Regina Ching Hua Lee ◽  
Huixin Chen ◽  
Karen Caiyun Chen ◽  
...  
Keyword(s):  
Protein Expression ◽  
Viral Entry ◽  
Viral Protein ◽  
Sindbis Virus ◽  
Chikungunya Virus ◽  
Early Stage ◽  
Antiviral Treatment ◽  
Chikv Infection ◽  
Viral Protein Synthesis ◽  
Viral Protein Expression

ABSTRACTChikungunya virus (CHIKV) is a mosquito-transmitted virus that has reemerged as a significant public health threat in the last decade. Since the 2005-2006 chikungunya fever epidemic in the Indian Ocean island of La Réunion, millions of people in more than 40 countries have been infected. Despite this, there is currently no antiviral treatment for chikungunya infection. In this study, an immunofluorescence-based screening platform was developed to identify potential inhibitors of CHIKV infection. A primary screen was performed using a highly purified natural product compound library, and 44 compounds exhibiting ≥70% inhibition of CHIKV infection were identified as positive hits. Among these, four were selected for dose-dependent inhibition assays to confirm their anti-CHIKV activity. Harringtonine, a cephalotaxine alkaloid, displayed potent inhibition of CHIKV infection (50% effective concentration [EC50] = 0.24 μM) with minimal cytotoxicity and was selected for elucidation of its antiviral mechanism. Time-of-addition studies, cotreatment assays, and direct transfection of viral genomic RNA indicated that harringtonine inhibited an early stage of the CHIKV replication cycle which occurred after viral entry into cells. In addition, quantitative reverse transcription-PCR (qRT-PCR) and Western blot analyses indicated that harringtonine affects CHIKV RNA production as well as viral protein expression. Treatment of harringtonine against Sindbis virus, a related alphavirus, suggested that harringtonine could inhibit other alphaviruses. This study suggests for the first time that harringtonine exerts its antiviral effects by inhibiting CHIKV viral protein synthesis.

scholarly journals Antiviral Activity of Compound L3 against Dengue and Zika Viruses In Vitro and In Vivo

2020 ◽  
Vol 21 (11) ◽  
pp. 4050 ◽  
Author(s):  
Fu-Kai Chuang ◽  
Ching-Len Liao ◽  
Ming-Kuan Hu ◽  
Yi-Lin Chiu ◽  
An-Rong Lee ◽  
...  
Keyword(s):  
Protein Expression ◽  
Tyrosine Kinase ◽  
Viral Protein ◽  
Therapeutic Efficacy ◽  
Antiviral Drug ◽  
Severe Illness ◽  
Viral Protein Expression ◽  
Mcf 7

Dengue virus (DENV) and Zika virus (ZIKV) are mosquito-borne flaviviruses that cause severe illness after infection. Currently, there are no specific or effective treatments against DENV and ZIKV. Previous studies have shown that tyrosine kinase activities and signal transduction are involved in flavivirus replication, suggesting a potential therapeutic strategy for DENV and ZIKV. In this study, we found that compound L3 can significantly reduce viral protein expression and viral titers in HEK-293, MCF-7, HepG2, and Huh-7 cells and exhibits superior therapeutic efficacy against flaviviral infection compared to other tyrosine kinase inhibitors. In addition, compound L3 can decrease endogenous HER2 activation and inhibit the phosphorylation of the HER2 downstream signaling molecules Src and ERK1/2, the levels of which have been associated with viral protein expression in MCF-7 cells. Moreover, silencing HER2 diminished DENV-2 and ZIKV expression in MCF-7 cells, which suggests that HER2 activity is involved in flavivirus replication. Furthermore, in DENV-2-infected AG129 mice, treatment with compound L3 increased the survival rates and reduced the viremia levels. Overall, compound L3 demonstrates therapeutic efficacy both in vitro and in vivo and could be developed as a promising antiviral drug against emerging flaviviruses or for concurrent DENV and ZIKV outbreaks.

scholarly journals Pravastatin Promotes Endothelial Colony-Forming Cell Function, Angiogenic Signaling and Protein Expression In Vitro

2021 ◽  
Vol 10 (2) ◽  
pp. 183
Author(s):  
Nadia Meyer ◽  
Lars Brodowski ◽  
Katja Richter ◽  
Constantin S. von Kaisenberg ◽  
Bianca Schröder-Heurich ◽  
...  
Keyword(s):  
Cardiovascular Diseases ◽  
Growth Factor ◽  
Endothelial Dysfunction ◽  
Protein Expression ◽  
Tube Formation ◽  
In Vitro Assays ◽  
Heme Oxygenase 1 ◽  
Expression Levels ◽  
Functional Capacities

Endothelial dysfunction is a primary feature of several cardiovascular diseases. Endothelial colony-forming cells (ECFCs) represent a highly proliferative subtype of endothelial progenitor cells (EPCs), which are involved in neovascularization and vascular repair. Statins are known to improve the outcome of cardiovascular diseases via pleiotropic effects. We hypothesized that treatment with the 3-hydroxy-3-methyl-glutaryl–coenzyme A (HMG-CoA) reductase inhibitor pravastatin increases ECFCs’ functional capacities and regulates the expression of proteins which modulate endothelial health in a favourable manner. Umbilical cord blood derived ECFCs were incubated with different concentrations of pravastatin with or without mevalonate, a key intermediate in cholesterol synthesis. Functional capacities such as migration, proliferation and tube formation were addressed in corresponding in vitro assays. mRNA and protein levels or phosphorylation of protein kinase B (AKT), endothelial nitric oxide synthase (eNOS), heme oxygenase-1 (HO-1), vascular endothelial growth factor A (VEGF-A), placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1) and endoglin (Eng) were analyzed by real time PCR or immunoblot, respectively. Proliferation, migration and tube formation of ECFCs were enhanced after pravastatin treatment, and AKT- and eNOS-phosphorylation were augmented. Further, expression levels of HO-1, VEGF-A and PlGF were increased, whereas expression levels of sFlt-1 and Eng were decreased. Pravastatin induced effects were reversible by the addition of mevalonate. Pravastatin induces beneficial effects on ECFC function, angiogenic signaling and protein expression. These effects may contribute to understand the pleiotropic function of statins as well as to provide a promising option to improve ECFCs’ condition in cell therapy in order to ameliorate endothelial dysfunction.

scholarly journals HSV-2 glycoprotein J promotes viral protein expression and virus spread

Virology ◽  
2018 ◽  
Vol 525 ◽  
pp. 83-95 ◽  
Author(s):  
Yalan Liu ◽  
Xinmeng Guan ◽  
Chuntian Li ◽  
Fengfeng Ni ◽  
Sukun Luo ◽  
...  
Keyword(s):  
Protein Expression ◽  
Viral Protein ◽  
Virus Spread ◽  
Viral Protein Expression

The Effect of High CDC6 Levels on Predicting Poor Prognosis in Colorectal Cancer

Chemotherapy ◽  
2022 ◽  
pp. 1-10
Author(s):  
Cheng Yang ◽  
Na Xie ◽  
Zhifei Luo ◽  
Xiling Ruan ◽  
Yixin Zhang ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Protein Expression ◽  
Poor Prognosis ◽  
Cancer Metastasis ◽  
Mrna Level ◽  
Normal Mucosa ◽  
Tnm Stage ◽  
Expression Levels ◽  
Normal Tissues

<b><i>Introduction:</i></b> We investigated the function of cell division cycle 6 (CDC6) on the prognosis in colorectal carcinoma (CRC). <b><i>Methods:</i></b> CDC6 protein expression levels in 121 patients with colorectal cancer and adjacent normal mucosa were detected by immunohistochemistry. <b><i>Results:</i></b> Compared to adjacent normal tissues, CDC6 mRNA level was overexpressed in CRC tissues. Moreover, CDC6 protein levels were expressed up to 93.39% (113/121) in CRC tissues in the cell nucleus or cytoplasm. However, there were only 5.79% (7/121) in normal mucosal tissues with nuclear expression. CDC6 expression was significantly correlated with TNM stage and tumor metastasis. The 5-year survival rate was lower in the high CDC6 expression group than the low group. After silencing of CDC6 expression in SW620 cells, cell proliferation was slowed, the tumor clones were decreased, and the cell cycle was arrested in G1 phase. In multivariate analysis, increased CDC6 protein expression levels in colon cancer tissues were associated with cancer metastasis, TNM stage, and patient survival time. <b><i>Conclusion:</i></b> CDC6 is highly expressed in CRC, and downregulation of CDC6 can slow the growth of CRC cells in vitro. It is also an independent predictor for poor prognosis and may be a useful biomarker for targeted therapy and prognostic evaluation.

scholarly journals Mammalian orthoreovirus Infection is Enhanced in Cells Pre-Treated with Sodium Arsenite

Viruses ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 563 ◽  
Author(s):  
Michael M. Lutz ◽  
Megan P. Worth ◽  
Meleana M. Hinchman ◽  
John S.L. Parker ◽  
Emily D. Ledgerwood
Keyword(s):  
Protein Expression ◽  
Stress Responses ◽  
Viral Protein ◽  
Sodium Arsenite ◽  
Translation Initiation Factor ◽  
Initiation Factor ◽  
Viral Protein Expression ◽  
Viral Yield ◽  
Pre Treatment ◽  
In Cells

Following reovirus infection, cells activate stress responses that repress canonical translation as a mechanism to limit progeny virion production. Work by others suggests that these stress responses, which are part of the integrated stress response (ISR), may benefit rather than repress reovirus replication. Here, we report that compared to untreated cells, treating cells with sodium arsenite (SA) to activate the ISR prior to infection enhanced viral protein expression, percent infectivity, and viral titer. SA-mediated enhancement was not strain-specific, but was cell-type specific. While SA pre-treatment of cells offered the greatest enhancement, treatment within the first 4 h of infection increased the percent of cells infected. SA activates the heme-regulated eIF2α (HRI) kinase, which phosphorylates eukaryotic translation initiation factor 2 alpha (eIF2α) to induce stress granule (SG) formation. Heat shock (HS), another activator of HRI, also induced eIF2α phosphorylation and SGs in cells. However, HS had no effect on percent infectivity or viral yield but did enhance viral protein expression. These data suggest that SA pre-treatment perturbs the cell in a way that is beneficial for reovirus and that this enhancement is independent of SG induction. Understanding how to manipulate the cellular stress responses during infection to enhance replication could help to maximize the oncolytic potential of reovirus.

scholarly journals MicroRNA-204-5p regulates apoptosis by targeting Bcl2 in rat ovarian granulosa cells exposed to cadmium†

2020 ◽  
Vol 103 (3) ◽  
pp. 608-619
Author(s):  
Ping Zhong ◽  
Jin Liu ◽  
Hong Li ◽  
Senbin Lin ◽  
Lingfeng Zeng ◽  
...  
Keyword(s):  
Protein Expression ◽  
Granulosa Cells ◽  
B Cell Lymphoma ◽  
Experimental Conditions ◽  
Expression Levels ◽  
Ovarian Granulosa Cells ◽  
Mrna And Protein Expression ◽  
Induced Apoptosis ◽  
Apoptosis Regulation

Abstract This study aimed to investigate whether cadmium (Cd) cytotoxicity in rat ovarian granulosa cells (OGCs) is mediated through apoptosis or autophagy and to determine the role of microRNAs (miRNAs) in Cd cytotoxicity. To test this hypothesis, rat OGCs were exposed to 0, 10, and 20 μM CdCl2 in vitro. As the Cd concentration increased, OGC apoptosis increased. In addition, Cd promoted apoptosis by decreasing the mRNA and protein expression levels of inhibition of B-cell lymphoma 2 (Bcl2). However, under our experimental conditions, no autophagic changes in rat OGCs were observed, and the mRNA and protein expression levels of the autophagic markers microtubule-associated protein 1 light chain 3 alpha (Map1lc3b) and Beclin1 (Becn1) were not changed. Microarray chip analysis, miRNA screening, and bioinformatics approaches were used to further explore the roles of apoptosis regulation-related miRNAs. In total, 19 miRNAs putatively related to Cd-induced apoptosis in rat OGCs were identified. Notably, miR-204-5p, which may target Bcl2, was identified. Then, rat OGCs were cultured in vitro and used to construct the miR-204-5p-knockdown cell line LV2-short hairpin RNA (shRNA). LV2-shRNA cells were exposed to 20 μM Cd for 12 h, and the mRNA and protein expression levels of Bcl2 were increased. Our findings suggest that Cd is cytotoxic to rat OGCs, and mitochondrial apoptosis rather than autophagy mediates Cd-induced damage to OGCs. Cd also affects apoptosis-related miRNAs, and the underlying apoptotic mechanism may involve the Bcl2 gene.

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