scholarly journals Epigenetic targeting of the ACE2 and NRP1 viral receptors limits SARS-CoV-2 infectivity

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Maria Laura Saiz ◽  
Marta L. De Diego ◽  
Darío López-García ◽  
Viviana Corte-Iglesias ◽  
Aroa Baragaño Raneros ◽  
...  

Abstract Background SARS-CoV-2 uses the angiotensin-converting enzyme 2 (ACE2) and neuropilin-1 (NRP1) receptors for entry into cells, and the serine protease TMPRSS2 for S protein priming. Inhibition of protease activity or the engagement with ACE2 and NRP1 receptors has been shown to be an effective strategy for blocking infectivity and viral spreading. Valproic acid (VPA; 2-propylpentanoic acid) is an epigenetic drug approved for clinical use. It produces potent antiviral and anti-inflammatory effects through its function as a histone deacetylase (HDAC) inhibitor. Here, we propose VPA as a potential candidate to tackle COVID-19, in which rapid viral spread and replication, and hyperinflammation are crucial elements. Results We used diverse cell lines (HK-2, Huh-7, HUVEC, Caco-2, and BEAS-2B) to analyze the effect of VPA and other HDAC inhibitors on the expression of the ACE-2 and NRP-1 receptors and their ability to inhibit infectivity, viral production, and the inflammatory response. Treatment with VPA significantly reduced expression of the ACE2 and NRP1 host proteins in all cell lines through a mechanism mediated by its HDAC inhibitory activity. The effect is maintained after SARS-CoV-2 infection. Consequently, the treatment of cells with VPA before infection impairs production of SARS-CoV-2 infectious viruses, but not that of other ACE2- and NRP1-independent viruses (VSV and HCoV-229E). Moreover, the addition of VPA 1 h post-infection with SARS-CoV-2 reduces the production of infectious viruses in a dose-dependent manner without significantly modifying the genomic and subgenomic messenger RNAs (gRNA and sg mRNAs) or protein levels of N protein. The production of inflammatory cytokines (TNF-α and IL-6) induced by TNF-α and SARS-CoV-2 infection is diminished in the presence of VPA. Conclusions Our data showed that VPA blocks three essential processes determining the severity of COVID-19. It downregulates the expression of ACE2 and NRP1, reducing the infectivity of SARS-CoV-2; it decreases viral yields, probably because it affects virus budding or virions stability; and it dampens the triggered inflammatory response. Thus, administering VPA could be considered a safe treatment for COVID-19 patients until vaccines have been rolled out across the world.

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Jianwei Zhang ◽  
Lei Han ◽  
Feng Chen

Abstract Background Let-7a-5p is demonstrated to be a tumor inhibitor in nasopharyngeal carcinoma. However, the role of let-7a-5p in chronic rhinosinusitis with nasal polyps (CRSwNP) has not been reported. This study is designed to determine the pattern of expression and role of let-7a-5p in CRSwNP. Methods The expression level of let-7a-5p, TNF-α, IL-1β, and IL-6 in CRSwNP tissues and cells were detected by RT-qPCR. Western blot assay was carried out to measure the protein expression of the Ras-MAPK pathway. Dual luciferase reporter assay and RNA pull-down assay were used to explore the relationship between let-7a-5p and IL-6. Results Let-7a-5p was significantly downregulated in CRSwNP tissues and cells. Moreover, the mRNA expression of TNF-α, IL-1β and IL-6 was increased in CRSwNP tissues, while let-7a-5p mimic inhibited the expression of TNF-α, IL-1β and IL-6. Besides that, let-7a-5p was negatively correlated with TNF-α, IL-1β and IL-6 in CRSwNP tissues. In our study, IL-6 was found to be a target gene of let-7a-5p. Additionally, let-7-5p mimic obviously reduced the protein levels of Ras, p-Raf1, p-MEK1 and p-ERK1/2, while IL-6 overexpression destroyed the inhibitory effect of let-7a-5p on the Ras-MAPK pathway in CRSwNP. Conclusion We demonstrated that let-7a-5p/IL-6 interaction regulated the inflammatory response through the Ras-MAPK pathway in CRSwNP.


2021 ◽  
Vol 2021 ◽  
pp. 1-12
Author(s):  
Qi Wang ◽  
Bingfeng Lin ◽  
Zhifeng Li ◽  
Jie Su ◽  
Yulin Feng

Gouty arthritis is characterized by the deposition of monosodium urate (MSU) within synovial joints and tissues due to increased urate concentrations. Here, we elucidated the role of the natural compound cichoric acid (CA) on the MSU crystal-stimulated inflammatory response. The THP-1-derived macrophages (THP-Ms) were pretreated with CA and then stimulated with MSU suspensions. The protein levels of p65 and IκBα, the activation of the NF-κB signaling pathway by measuring the expression of its downstream inflammatory cytokines, and the activity of NLRP3 inflammasome were measured by western blotting and ELISA. CA treatment markedly inhibited the degradation of IκBα and the activation of NF-κB signaling pathway and reduced the levels of its downstream inflammatory genes such as IL-1β, TNF-α, COX-2, and PGE2 in the MSU-stimulated THP-M cells. Therefore, we infer that CA effectively alleviated MSU-induced inflammation by suppressing the degradation of IκBα, thereby reducing the activation of the NF-κB signaling pathway and the NLRP3 inflammasome. These results suggest that CA could be a novel therapeutic strategy in averting acute episodes of gout.


2020 ◽  
Author(s):  
Fang Ren ◽  
Gong Zhang ◽  
Caiyu Li ◽  
Gailing Li ◽  
Yuan Cao ◽  
...  

Abstract Background: Hesperetin, an active compound found in citrus fruits, possesses antiproliferative effects toward several types of cancer cell lines, including cervical cancer. In this study, we explore the antitumor effects of Hesperetin on the human cervical cancer human papilloma virus (HPV)-positive (CaSki and HeLa) and HPV-negative (C-33A) cell lines and further elucidated the underlying mechanisms of this action. Methods: Cell viability and proliferation was measured by the MTT assay and 5-ethynyl-2′-deoxyuridine (EdU) incorporation assay, respectively. dUTP-fluorescein nick end-labeling (TUNEL) staining, Annexin V‑fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining and flow cytometry was used to assess the degree of apoptosis. JC-1 staining assay was used to evaluate the change of mitochondrial membrane potential (ΔΨm) and Western blot assays were used to determine apoptosis-related factors at protein level. Results: Hesperetin (100, 200 and 400 μM) exhibited a significant exclusive inhibitory effect against the growth of HPV-infected CaSki and HeLa cancer cells via induction of apoptosis in a concentration-dependent manner, while it was almost not active in HPV-negative C-33A cancer cells and normal cervix epithelial H8 cells. Moreover, this antitumor effect executed by Hesperetin was associated with disruption of ΔΨm, the release of cytochrome c from mitochondria, activation of pro-apoptotic proteins (Bax, cleaved caspase-3 and caspase-9) and inhibition of anti-apoptotic proteins (Bcl-2). During this process, cleaved caspase-8 remained unchanged. In addition, Hesperetin led to a downregulation of E6 oncoprotein expression and upregulation of tumor suppressor protein p53 level. Conclusions: Collectively, these results implicated that Hesperetin can induce apoptosis of HPV‑positive cervical cancer cells via a mitochondria-mediated intrinsic signaling pathway, together with the repression of E6 and enhancement of p53 protein level, indicating Hesperetin may be considered as a potential candidate for the development of innovative anti-HPV cervical cancer agents.


2018 ◽  
Vol 73 (7-8) ◽  
pp. 273-279 ◽  
Author(s):  
Chang-Suk Kong ◽  
Jung Im Lee ◽  
Fatih Karadeniz ◽  
Hojun Kim ◽  
Youngwan Seo

Abstract The Arctic flora hosts a limited number of species due to its extreme environmental conditions which also yield novel and unique secondary metabolites from withstanding plants. Considering a lack of research on bioactivity potential of Arctic flora, Ranunculus hyperboreus, an Arctic plant, was studied for its anti-inflammatory potential as a part of ongoing research on discovering novel natural bioactive products. Solvent-based fractions (H2O, n-BuOH, 85% aq. MeOH, n-hexane) from R. hyperboreus extract were observed to decrease the elevated nitrate amount during the inflammatory response of lipopolysaccharide-induced mouse macrophage RAW264.7 cells. To some extent, treatment with fractions was able to regulate the expression and protein levels of inflammation-related enzymes, iNOS and COX-2, and pro-inflammatory cytokines, TNF-α, IL-1β, and IL-6. The most active fractions, H2O and 85% aq. MeOH, were suggested to exert their effect through suppressed activation of MAPK pathways, especially JNK. Based on the studies of same species, phenolic glycosides were suggested to be the main active ingredients. To our knowledge, this is the first report of any bioactivity of R. hyperboreus which could be a valuable source of natural bioactive agents against inflammation.


2019 ◽  
Vol 20 (23) ◽  
pp. 5904 ◽  
Author(s):  
Na Dong ◽  
Chensi Wang ◽  
Xinran Li ◽  
Yuming Guo ◽  
Xiaoli Li

The therapeutic application of antimicrobial peptides (AMPs), a potential type of peptide-based biomaterial, is impeded by their poor antimicrobial activity and potential cytotoxicity as a lack of understanding of their structure–activity relationships. In order to comprehensively enhance the antibacterial and clinical application potency of AMPs, a rational approach was applied to design amphiphilic peptides, including head-to-tail cyclic, linear and D-proline antimicrobial peptides using the template (IR)nP(IR)nP (n = 1, 2 and 3). Results showed that these amphiphilic peptides demonstrated antimicrobial activity in a size-dependent manner and that cyclic peptide OIR3, which contained three repeating units (IR)3, had greater antimicrobial potency and cell selectivity than liner peptide IR3, DIR3 with D-Pro and gramicidin S (GS). Surface plasmon resonance and endotoxin neutralization assays indicated that OIR3 had significant endotoxin neutralization capabilities, which suggested that the effects of OIR3 were mediated by binding to lipopolysaccharides (LPS). Using fluorescence spectrometry and electron microscopy, we found that OIR3 strongly promoted membrane disruption and thereby induced cell lysis. In addition, an LPS-induced inflammation assay showed that OIR3 inhibited the pro-inflammatory factor TNF-α in RAW264.7 cells. OIR3 was able to reduce oxazolone-induced skin inflammation in allergic dermatitis mouse model via the inhibition of TNF-α, IL-1β and IL-6 mRNA expression. Collectively, the engineered head-to-tail cyclic peptide OIR3 was considerable potential candidate for use as a clinical therapeutic for the treatment of bacterial infections and skin inflammation.


Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 478 ◽  
Author(s):  
Rasha Al-Rikabi ◽  
Hanady Al-Shmgani ◽  
Yaser Hassan Dewir ◽  
Salah El-Hendawy

(1) Background: Plant flavonoids are efficient in preventing and treating various diseases. This study aimed to evaluate the ability of hesperidin, a flavonoid found in citrus fruits, in inhibiting lipopolysaccharide (LPS) induced inflammation, which induced lethal toxicity in vivo, and to evaluate its importance as an antitumor agent in breast cancer. The in vivo experiments revealed the protective effects of hesperidin against the negative LPS effects on the liver and spleen of male mice. (2) Methods: In the liver, the antioxidant activity was measured by estimating the concentration of glutathione (GSH) and catalase (CAT), whereas in spleen, the concentration of cytokines including IL-33 and TNF-α was measured. The in vitro experiments including MTT assay, clonogenity test, and sulforhodamine 101 stain with DAPI (4′, 6-diamidino-2-phenylindole) were used to assess the morphological apoptosis in breast cancer cells. (3) Results: The results of this study revealed a significant increase in the IL-33 and TNF-α cytokine levels in LPS challenged mice along with a considerable elevation in glutathione (GSH); moreover, the catalase (CAT) level was higher compared to that of the control group. Cytotoxicity of the MCF-7 cell line revealed significant differences among the groups treated with different concentrations when compared to the control groups, in a concentration-dependent manner. Hesperidin significantly inhibited the colony formation of MCF7 cells when compared to that of control. Clear changes were observed in the cell shape, including cell shrinkage and chromatin condensation, which were associated with a later apoptotic stage. (4) Conclusion: The results indicate that hesperidin might be a potential candidate in preventing diseases.


Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4456-4456
Author(s):  
Massimiliano Bonifacio ◽  
Antonella Rigo ◽  
Elisabetta Cavalieri ◽  
Emanuele Guardalben ◽  
Christian Bergamini ◽  
...  

Abstract Abstract 4456 Background. The plant-derived agent α-bisabolol is a small oily sesquiterpene alcohol that has been demonstrated to be cytotoxic against human malignant non-hematological and leukemic cells (Bonifacio M et al, Blood, 2009 ASH annual meeting abstracts;114:4800). Here we tested its activity against BCR-ABL+ cell lines and primary cells from patients, alone or in combination with the Tyrosine-Kinase Inhibitors (TKIs) Imatinib and Nilotinib. Also, the mechanism of α-bisabolol cytotoxicity in BCR-ABL+ cells was assessed. Methods. We used the BCR-ABL+ K562, LAMA-84 and CML-T1 cell lines and primary leukemic cells from 14 patients with BCR-ABL+ Acute Lymphoblastic Leukemia at diagnosis. First, the citotoxicity of single-agent α-bisabolol was determined by MTT. Then, mitochondrial membrane potential of treated cells was evaluated by the JC-1 dye in flow cytometry and fluorescence microscopy. Permeabilized leukemic cells were assayed for oxygen consumption by measuring mitochondrial state 3 and uncoupled respiration. Reactive oxygen species (ROS) production in α-bisabolol treated cells were quantified in flow cytometry by oxidation of CM-H2DCFDA, measuring the fluorescence intensity of the DCF products. Apoptosis was studied by the poly(ADP-ribose) polymerase (PARP) cleavage and internucleosomal DNA laddering analysis. Finally, the combination effects between α-bisabolol and Imatinib or Nilotinib (kindly provided by Novartis) were analyzed according to the median-effect method of Chou and Talalay using the CalcuSyn software. Results. α-bisabolol reduced the viability of BCR-ABL+ cells in a dose-dependent manner. The mean IC50 values of α-bisabolol were 46±11 μ M for primary leukemic cells and ranged from 62 to 115 μ M in the cell lines. JC-1 staining of BCR-ABL+ primary leukemic cells treated with 40 μ M α-bisabolol for 3 to 5 hours demonstrated a dissipation of the mitochondrial transmembrane potential (ΔΨm), thus indicating the start of the apoptotic process. Moreover, NADH-supported state 3 respiration in α-bisabolol treated leukemic cells was significantly decreased in comparison with untreated leukemic controls (140.0±70.5 vs 280.7±11.9 pmol O2/min/106 cells; p<.05). Finally, PARP cleavage and DNA laddering followed α-bisabolol exposure of leukemic BCR-ABL+ blasts. The apoptosis induction was accompanied by ROS production. When tested in combination at constant ratio with Imatinib or Nilotinib, α-bisabolol showed overall slight to strong synergistic effects, without evidence for antagonism across a range of doses (Table 1). In 3 patients with mutation of BCR-ABL (T315I, E255V and Y253H, respectively) we observed full activity of α-bisabolol as single agent and confirmed the synergism between α-bisabolol and Imatinib. Conclusion. This study indicates that α-bisabolol is an effective pro-apoptotic agent for human acute BCR-ABL+ leukemia cells via induction of mitochondrial membrane damage. The combination of α-bisabolol with Imatinib or Nilotinib allows a dose reduction up to 90% of each drug to obtain the same cytotoxic effect, so indicating a clear synergism. α-bisabolol may be a potential candidate for the treatment of BCR-ABL+ leukemias and the effective dose of TKIs could be reduced in a combined treatment with α-bisabolol. Disclosures: No relevant conflicts of interest to declare.


Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 3222-3222
Author(s):  
Bruno A Cardoso ◽  
Helio Belo ◽  
Antonio Almeida

Abstract Background: The classical BCR-ABL-negative myeloproliferative neoplasms (MPN) are characterized by increased proliferation of hematopoietic precursors in the bone marrow resulting in an elevated number of terminally differentiated cells. Despite the recent description of JAK2 activating mutations and other mutations, these do not completely explain the pathophysiology and clinical heterogeneity of MPN. Epigenetic modifications, particularly histone acetylation, play pivotal roles in the pathogenesis of several hematological malignancies, and treatment of such disorders with histone deacetylase inhibitors results cell death and proliferation arrest. Importantly, epigenetic agents have proven to be effective in several hematological malignancies. Aims: HDAC inhibition has demonstrated some efficacy in patients with MPN. In order to investigate the effects of HDAC inhibitors in MPN, we analyzed the impact of Vorinostat on the cellular biology of MPN cell lines and primary bone marrow samples. Material and Methods: MPN bone marrow samples were collected at diagnosis following informed consent in the course of routine clinical laboratory tests. Mononuclear cells were isolated by gradient separation were used for culture experiments and lysed for RNA extraction. RNA extracted from MPN primary samples was used to synthetize cDNA and the transcript levels of genes associated with Apoptosis, Proliferation, Epigenetic modifications and several Signaling pathways were analyzed by quantitative-PCR. MPN primary cells and MPN derived cell lines were incubated with Vorinostat and at different time points the cells were harvest, lysed for gene expression analysis and stained with different antibodies, Annexin-V/PI and DCF-DA to analyze cellular differentiation, apoptosis and Reactive Oxygen Species (ROS) respectively. Results: We performed a targeted-genome wide screen and compared the transcript levels of a defined set of genes between normal bone marrow and MPN primary samples. We identified 9 genes (BIRC3, TNFRSF9, DLL4, IL1B, CDKN1A, FOSL1, CREL, SERPINB9 and EGR1) whose expression increased for at least 4 fold and 2 genes (HIP1 and DTX1) whose expression decreased by at least 0.5 fold in MPN patients relative to normal bone marrow samples. Interestingly, incubation of Vorinostat in MPN cell lines at physiological concentrations increases the expression of such genes, and also the expression of genes associated with apoptosis and growth arrest while decreasing the expression of genes associated with proliferation, growth arrest and JAK-STAT signaling pathway. Regarding cellular physiology, Vorinostat induces apoptosis in MPN cultured cell lines in a time- and dose-dependent manner. Furthermore, incubation of primary MPN bone marrow samples with Vorinostat induced apoptosis, blocked differentiation and also diminished ROS levels in a dose dependent manner. These effects were most marked in the monocytic lineage, a population which expresses the highest levels of ROS. Vorinostat also reduced the levels of GPA and CD61, markers of erythroid and megakaryocytic differentiation, respectively. Summary/Conclusions: Here, we show that Vorinostat incubation impairs MPN cellular differentiation and reduces ROS and cellular viability, possibly through the down-regulation of genes associated with cellular proliferation, particularly the JAK-STAT target genes, and up-regulation of genes important for apoptosis and growth arrest. Interestingly, the genes that we identified to be up-regulated in MPN primary samples relative to normal controls, are further increased by Vorinostat treatment, suggesting that these could act as potential biomarkers for Vorinostat effectiveness in the MPN context. Furthermore, these results hold therapeutic promise as Vorinostat reduced differentiation markers associated with Polycythemia Vera and Essential Thrombocytosis. The observation that Vorinostat is particularly effective against the monocytic lineage is interesting in the context of the recently described role of bone marrow monocytes in the pathogenesis of Polycythemia Vera in mouse models. Our results point towards the potential role of Vorinostat (and possibly other HDAC inhibitors) in the treatment of MPN. This potential would require clinical trials to investigate its efficacy. Disclosures Almeida: Celgene: Consultancy; Novartis: Consultancy; Amgen: Membership on an entity's Board of Directors or advisory committees; Shire: Membership on an entity's Board of Directors or advisory committees; Bristol-Meyer Squibb: Membership on an entity's Board of Directors or advisory committees.


2019 ◽  
Author(s):  
Jun Chen ◽  
Xue Wang ◽  
Jian Hu ◽  
Wenting Huang ◽  
Confidence Dordoe ◽  
...  

Abstract Background :Blood-brain barrier (BBB) disruption and the cerebral inflammatory response are two reciprocal mechanisms that work together to mediate the degree of brain edema, which is responsible for the majority of deaths after traumatic brain injury (TBI), and facilitate further brain damage, which leads to long-term TBI complications. Fibroblast growth factor 20 (FGF20), a neurotrophic factor, plays important roles in the development of dopaminergic neurons in Parkinson disease (PD). However, little is known about the role of FGF20 in TBI. The aim of the current study was to assess the protective effects of FGF20 in TBI through protecting the BBB. Methods: We explored the relationship between FGF20 and BBB function in controlled cortical impact (CCI)-induced TBI mice model and TNF-α-induced human brain microvascular endothelial cell (HBMEC) in vitro BBB disruption model. We also explored the mechanisms of these interactions and the signaling processes involved in BBB function and neuroinflammation. Results: In this study, we demonstrate that recombinant human FGF20 (rhFGF20) reduced neurofunctional deficits, brain edema and Evans Blue penetration in vivo after TBI. In an in vitro BBB disruption model of, rhFGF20 could reverse changes to TNF-α-induced HBMEC morphology, reduce Transwell permeability, and increase transendothelial electrical resistance (TEER). In both a TBI mouse model and in vitro , rhFGF20 upregulated the expression of BBB-associated tight junction (TJ) protein and adherens junction (AJ) protein via the AKT/GSK3β pathway. In addition, rhFGF20 inhibited the cerebral inflammatory response through regulating the JNK/NFκB pathway and further protected the function of the BBB. Conclusions : Our results contribute to a new treatment strategy in TBI research. FGF20 is a potential candidate to treat TBI as it protects the BBB via regulating the AKT/GSK3β and JNK/NFκB signaling pathways.


Molecules ◽  
2021 ◽  
Vol 26 (19) ◽  
pp. 5785
Author(s):  
Fah Chueahongthong ◽  
Singkome Tima ◽  
Sawitree Chiampanichayakul ◽  
Cory Berkland ◽  
Songyot Anuchapreeda

This study aims to enhance efficacy and reduce toxicity of the combination treatment of a drug and curcumin (Cur) on leukemic stem cell and leukemic cell lines, including KG-1a and KG-1 (FLT3+ LSCs), EoL-1 (FLT3+ LCs), and U937 (FLT3− LCs). The cytotoxicity of co-treatments of doxorubicin (Dox) or idarubicin (Ida) at concentrations of the IC10–IC80 values and each concentration of Cur at the IC20, IC30, IC40, and IC50 values (conditions 1, 2, 3, and 4) was determined by MTT assays. Dox–Cur increased cytotoxicity in leukemic cells. Dox–Cur co-treatment showed additive and synergistic effects in several conditions. The effect of this co-treatment on FLT3 expression in KG-1a, KG-1, and EoL-1 cells was examined by Western blotting. Dox–Cur decreased FLT3 protein levels and total cell numbers in all the cell lines in a dose-dependent manner. In summary, this study exhibits a novel report of Dox–Cur co-treatment in both enhancing cytotoxicity of Dox and inhibiting cell proliferation via FLT3 protein expression in leukemia stem cells and leukemic cells. This is the option of leukemia treatment with reducing side effects of chemotherapeutic drugs to leukemia patients.


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