Flos Farfarae Inhibits Enterovirus 71-Induced Cell Injury by Preventing Viral Replication and Structural Protein Expression

Enterovirus 71 (EV71) infection can cause airway symptoms, brainstem encephalitis, neurogenic shock, and neurogenic pulmonary edema with high morbidity and mortality. There is no proven therapeutic modality. Flos Farfarae is the dried flower bud of Tussilago farfara L. that has been used to manage airway illnesses for thousands of years. It has neuro-protective activity and has been used to manage neuro-inflammatory diseases. However, it is unknown whether Flos Farfarae has activity against EV71-induced neuropathy. The current study used both human foreskin fibroblast (CCFS-1/KMC) and human rhabdomyosarcoma (RD) cell lines to test the hypothesis that a hot water extract of Flos Farfarae could effectively inhibit EV71 infection. The authenticity of Flos Farfarae was confirmed by HPLC-UV fingerprint. Through plaque reduction assays and flow cytometry, Flos Farfarae was found to inhibit EV71 infection ([Formula: see text]). Inhibition of viral replication and protein expression were further confirmed by reverse transcription polymerase chain reaction (RT-PCR) and quantitative RT-PCR (qRT-PCR), and western blot, respectively. The estimated IC[Formula: see text]s were 106.3[Formula: see text][Formula: see text]g/mL in CCFS-1/KMC, and 15.0[Formula: see text][Formula: see text]g/mL in RD cells. Therefore, Flos Farfarae could be beneficial to inhibit EV71 infection by preventing viral replication and structural protein expression.

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Investigation on Factors Associated with Severe Hand, Foot and Mouth Disease

Infection International ◽

10.1515/ii-2017-0080 ◽

2014 ◽

Vol 3 (2) ◽

pp. 82-91

Author(s):

Gui-lin Yang ◽

Ying-xia Liu ◽

Mu-tong Fang ◽

Yan-xia He ◽

John Nunnari ◽

...

Keyword(s):

Detection Rate ◽

Multivariate Logistic Regression Analysis ◽

Enterovirus 71 ◽

Foot And Mouth Disease ◽

Ev71 Infection ◽

Pathological Examination ◽

Nasopharyngeal Swab ◽

Neurogenic Pulmonary Edema ◽

Factors Associated ◽

Logistic Analysis

Abstract Objective To analyze the clinical and laboratory features of patients with mild and severe HFMD to identify early predictive or diagnostic markers for severe cases. Methods Samples of feces, nasopharyngeal-swab specimens, peripheral blood, serum and cerebral spinal fluid were collected. Postmortem pathological examination was conducted on 2 dead patients with complication due to neurogenic pulmonary edema. Reverse transcription-polymerase chain-reaction (RT-PCR), culture and isolation of enterovirus 71 (EV71) were performed to detect EV71 infection. Both univariate and multivariate logistic analysis were used to identify factors associated with severe cases. Results EV71 was mainly responsible for HFMD. In this study, 5 isolated EV71 strains belonged to C4 gene subtype. Compared with mild patients, EV71-RNA detection rate was higher and CoxA16 detection rate was lower among severe patients (P < 0.01). Inflammatory cell infiltration in the lung, cardiac and liver tissues were mild by postmortem pathological examination. It was found that body temperature, vomitting, limb tremor, neutrophil, blood glucose and EV71 infection were significantly related to the severe cases by univariate logistic analysis. However, after multivariate logistic regression analysis, only vomiting (OR 16.1, CI 2.3-110.5, P < 0.01) and limb tremor (OR 117.6, CI 13.8-1004.5, P < 0.01) were significantly and independently correlated with the severe cases. Conclusions EV71 was mainly responsible for HFMD, particularly for severe cases. Vomiting and limb tremor were predictive markers for severe cases.

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Water Extract of Glycyrrhiza uralensis Inhibited Enterovirus 71 in a Human Foreskin Fibroblast Cell Line

The American Journal of Chinese Medicine ◽

10.1142/s0192415x09006904 ◽

2009 ◽

Vol 37 (02) ◽

pp. 383-394 ◽

Cited By ~ 22

Author(s):

Kung-Kai Kuo ◽

Jung-San Chang ◽

Kuo-Chih Wang ◽

Lien-Chai Chiang

Keyword(s):

Cell Line ◽

Enterovirus 71 ◽

Water Extract ◽

Fibroblast Cell ◽

Skin Lesions ◽

Human Infection ◽

Glycyrrhiza Uralensis ◽

Host Cells ◽

Ev71 Infection ◽

Viral Attachment

Human infection by enterovirus type 71 (EV71) can cause life-threatening meningo-encephalitis. Currently, there is no effective anti-EV71 therapy available. Since EV71 infection commonly involves skin lesions, we tested our hypothesis that water extract of Glycyrrhiza uralensis (G. uralensis) could inhibit the cytopathic effects of EV71 in a human foreskin cell line by using an XTT-based method. Our results showed that the water extract of G. uralensis at 3,000 μg/ml has only 30% cytotoxicity on host cells, and furthermore, that the water extract of G. uralensis at 0.1 μg/ml could effectively protect host cells against EV71 infection (p < 0.0001). The half maximal inhibitory concentration (IC50) was 0.056 μg/ml with a selective index greater than 50,000. The water extract of G. uralensis exerted its effects not only by preventing viral attachment (p < 0.0001), but also by inhibiting the penetration of the virus (p < 0.0001). EV71 infection caused cells to produce significant amounts of IFN-β (p = 0.0003). However, the anti-EV71 activity of the water extract of G. uralensis was not mediated by IFN. In conclusion, the water extract of G. uralensis possesses potent anti-EV71 effects with less cytotoxicity. Its low IC50 and high 50% cytotoxic concentration (CC50) values suggest that it is a promising anti-EV71 agent.

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Enterovirus 71 Activates GADD34 via Precursor 3CD to Promote IRES-Mediated Viral Translation

Microbiology Spectrum ◽

10.1128/spectrum.01388-21 ◽

2022 ◽

Author(s):

Hui Li ◽

Wenqian Li ◽

Shuangling Zhang ◽

Manman Qiu ◽

Zhuoran Li ◽

...

Keyword(s):

Viral Replication ◽

Therapeutic Targets ◽

Enterovirus 71 ◽

Host Factors ◽

Ev71 Infection ◽

Host Proteins ◽

Viral Translation ◽

Pathogenic Mechanisms ◽

Important Approach

Identification of host factors involved in viral replication is an important approach in discovering viral pathogenic mechanisms and identifying potential therapeutic targets. Previously, we screened host proteins that were upregulated by EV71 infection.

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Enterovirus 3A Facilitates Viral Replication by Promoting Phosphatidylinositol 4-Kinase IIIβ–ACBD3 Interaction

Journal of Virology ◽

10.1128/jvi.00791-17 ◽

2017 ◽

Vol 91 (19) ◽

Cited By ~ 24

Author(s):

Xia Xiao ◽

Xiaobo Lei ◽

Zhenzhen Zhang ◽

Yijie Ma ◽

Jianli Qi ◽

...

Keyword(s):

Viral Replication ◽

Enterovirus 71 ◽

Rna Replication ◽

Host Cells ◽

Ev71 Infection ◽

Genome Replication ◽

Replication Sites ◽

Phosphatidylinositol 4 ◽

Interfering Rna ◽

Stimulation Of

ABSTRACT Like other enteroviruses, enterovirus 71 (EV71) relies on phosphatidylinositol 4-kinase IIIβ (PI4KB) for genome RNA replication. However, how PI4KB is recruited to the genome replication sites of EV71 remains elusive. Recently, we reported that a host factor, ACBD3, is needed for EV71 replication by interacting with viral 3A protein. Here, we show that ACBD3 is required for the recruitment of PI4KB to RNA replication sites. Overexpression of viral 3A or EV71 infection stimulates the interaction of PI4KB and ACBD3. Consistently, EV71 infection induces the production of phosphatidylinositol-4-phosphate (PI4P). Furthermore, PI4KB, ACBD3, and 3A are all localized to the viral-RNA replication sites. Accordingly, PI4KB or ACBD3 depletion by small interfering RNA (siRNA) leads to a reduction in PI4P production after EV71 infection. I44A or H54Y substitution in 3A interrupts the stimulation of PI4KB and ACBD3. Further analysis suggests that stimulation of ACBD3-PI4KB interaction is also important for the replication of enterovirus 68 but disadvantageous to human rhinovirus 16. These results reveal a mechanism of enterovirus replication that involves a selective strategy for recruitment of PI4KB to the RNA replication sites. IMPORTANCE Enterovirus 71, like other human enteroviruses, replicates its genome within host cells, where viral proteins efficiently utilize cellular machineries. While multiple factors are involved, it is largely unclear how viral replication is controlled. We show that the 3A protein of enterovirus 71 recruits an enzyme, phosphatidylinositol 4-kinase IIIβ, by interacting with ACBD3, which alters cellular membranes through the production of a lipid, PI4P. Consequently, the viral and host proteins form a large complex that is necessary for RNA synthesis at replication sites. Notably, PI4KB-ACBD3 interaction also differentially mediates the replication of enterovirus 68 and rhinovirus 16. These results provide new insight into the molecular network of enterovirus replication.

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A Laboratory Evaluation of Medicinal Herbs Used in China for the Treatment of Hand, Foot, and Mouth Disease

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2013/504563 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Xiaoqing Chen ◽

Chunyang Wang ◽

Lanfang Xu ◽

Xiaoshuang Chen ◽

Wei Wang ◽

...

Keyword(s):

Viral Infection ◽

Enterovirus 71 ◽

Water Extract ◽

Foot And Mouth Disease ◽

Mouth Disease ◽

Chinese Herbs ◽

Ev71 Infection ◽

Laboratory Evaluation ◽

Proinflammatory Response ◽

Foot And Mouth

Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16) are the causative agents of hand, foot, and mouth disease (HFMD). During recent epidemics of HFMD in China, medicinal herbals and preparations containing herbal extracts have demonstrated therapeutic efficacy with relative safety profiles. There have been no microbiological studies to validate their usefulness for HFMD. We selected 12 commonly used herbs for HFMD from government recommended guidelines as well as published reports and tested for their antiviral activity and anti-inflammatory activity. A water extract ofHouttuynia cordataThunb. (HCT) inhibited EV71 infection significantly and was marginally active against CVA16 infection. The IC50(concentration to have 50% inhibitory effect) values of HCT against a Fuyang strain and a BrCr strain of EV71 were determined at 8.9 μg/mL and 20.6 μg/mL, respectively.Mentha haplocalyxBriq. (MHB) water extract was active against CVA16, with an IC50value of 70.3 μg/mL. The extract did not exhibit activity against EV71 infection. Although the majority of the extracts showed no activity against viral infection, several extracts demonstrated activity in blocking proinflammatory response by viral infection. This study therefore validates the effectiveness of Chinese herbs for HFMD since some formulations containing the correct combination of the herbs can block viral replication as well as proinflammatory response of HFMD.

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Enterovirus 71 Represses Interleukin Enhancer Binding Factor 2 Production and Nucleus Translocation to Antagonize ILF2 Antiviral Effects

10.20944/preprints201910.0161.v1 ◽

2019 ◽

Author(s):

Jing Jin ◽

Wenbiao Wang ◽

Sha Ai ◽

Qi Zhang ◽

Kailang Wu ◽

...

Keyword(s):

Health Hazard ◽

Enterovirus 71 ◽

Ev71 Infection ◽

Structural Protein ◽

Antiviral Effects ◽

Distinct Mechanism ◽

Binding Factor ◽

2B Protein ◽

Rd Cells ◽

Hand Foot Mouth Disease

Enterovirus 71 (EV71) infection hand-foot-mouth disease (HFMD), meningoencephalitis, neonatal sepsis, and even fatal encephalitis in children, thereby representing a serious public health hazard. It is important to determine the mechanisms underlying the regulation of EV71 infection. In this study, we initially reveal that the interleukin enhancer binding factor 2 (ILF2) down-regulates EV71 50% tissue culture infective dose (TCID50), attenuates EV71 plaque formation unit (PFU), thereby repressing EV71 infection. Moreover, we reveal a distinct mechanism by which EV71 antagonizes ILF2-mediated antiviral effects. Chip data analyses show that ILF2 mRNA is reduced upon EV71 infection. Cellular studies indicate that EV71 infection represses ILF2 mRNA expression and protein production in human leukemic monocytes (THP-1) differentiated macrophages and in human rhabdomyosarcoma (RD) cells. Additionally, EV71 non-structural protein 2B interacts with ILF2 in human embryonic kidney (HEK293T) cells. Interestingly, in the presence of EV71 2B, ILF2 is translocated from the nucleus to the cytoplasm and co-localizes with 2B in the cytoplasm. Therefore, we reveal a distinct mechanism by which EV71 antagonizes ILF2-mediated antiviral effects by inhibiting ILF2 expression and promoting ILF2 translocation from the nucleus to cytoplasm through its 2B protein.

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HAND, FOOT AND MOUTH DISEASE IN SOUTH BENGAL AND KOLKATA: A STUDY OVER 5 YEARS TO EVALUATE CASES WITH CLINICAL SUSPICION

10.36106/gjra/3901402 ◽

2021 ◽

pp. 39-41

Author(s):

Swagnik Roy ◽

Bibhas SahaDalal ◽

Rajat Dasgupta ◽

Sourabh Mitra ◽

Amrita Roy ◽

...

Keyword(s):

Disease Risk ◽

Enterovirus 71 ◽

Foot And Mouth Disease ◽

Mouth Disease ◽

Ev71 Infection ◽

Human Enterovirus ◽

Neurological Involvement ◽

Neurogenic Pulmonary Edema ◽

Foot And Mouth ◽

Hands And Feet

Hand, foot, and mouth disease is a very infective infection. It's caused by viruses from the Enterovirus genus, among the Enterovirus genus coxsackievirus is most commonly found associated with Hand , Foot and Mouth disease. Hand, foot and mouth disease (HFMD) causes rashes or vesicular lesions in the affected individuals and lesions are found in extremities and upper extremity lesion is more common along with feet and mouth. It is mostly seen in school going children, and causative agents are likely Enterovirus-A (EV-A) species, including Coxsackievirus-A16 (CV-A16) and Enterovirus-71 (EV-71) [1]. Hand , Foot and Mouth Disease is usullay mild and selimiting. In the affected patient's rst identied by a brief prodromal fever, followed by pharyngitis, mouth ulcers and rash on the hands and feet. The disease is caused by numerous members of the Enterovirus genus of the family Picornaviridae e.g. Coxsackievirus type A (CA) and Enterovirus 71 (EV71), and the clinical features are not identiable and distinguishable from virus to virus. [2] . Young children have the highest risk of getting hand, foot, and mouth disease. Risk increases if they attend daycare or school, as viruses can spread quickly in these facilities. Children usually build up immunity to the disease after being exposed to the viruses that cause it. This is why the condition rarely affects people over age 10. However, it's still possible for older children and adults to get the infection, especially if they have weakened immune systems. EV71 is a human enterovirus A species causing infection in clildren[3,4] . Clinically though it is mild symptoms and self limiting initially, such as a fever along with unraised colorless spots, and bumps on the hands, feet, and mouth. In some patients with severe disease several neurological complications (including cephalomeningitis, encephalitis, and neurogenic pneumonedema) and circulatory disorders. Occasionally, it even causes death [5]. Therefore, an early indicator of EV71 infection with neurological involvement is crucial for appropriate management [6]. Hand, foot, and mouth disease by enterovirus infection repots severe complications (such as brain stem encephalitis, neurogenic pulmonary edema, and other fatal complications) and a high mortality due to HFMD are more frequently related to EV71 infection[7,8] .

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