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1.
Cureus ; 16(6): e61656, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38966448

ABSTRACT

One of the most widespread enzymopathies affecting human beings is glucose-6-phosphate dehydrogenase (G6PD) deficiency, which is brought on by inherited mutations in the X-linked gene. Red blood cells (RBCs) with a G6PD deficiency are more sensitive to oxidative assault and consequently to hemolysis. There are more than 200 known G6PD mutations, of which around half are polymorphic and thus prevalent in a variety of populations. We present a case of diabetic ketoacidosis (DKA), with severe hemolytic anemia and methemoglobinemia. The patient was admitted to the intensive care unit, treated for DKA, and received a blood transfusion. In addition, the patient presented with high methemoglobin levels and features of severe hemolytic anemia from the onset, which made the diagnostic consideration of G6PD highly likely. Accordingly, the patient was treated with several doses of ascorbic acid instead of methylene blue. In a nutshell, a patient with DKA who has hemolytic anemia has to have it properly evaluated and controlled. The link between methemoglobinemia, G6PD deficiency, and DKA should be recognized by medical professionals, particularly when oxygen saturation gaps are found.

2.
J Med Chem ; 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38687966

ABSTRACT

Despite the record-breaking discovery, development and approval of vaccines and antiviral therapeutics such as Paxlovid, coronavirus disease 2019 (COVID-19) remained the fourth leading cause of death in the world and third highest in the United States in 2022. Here, we report the discovery and characterization of PF-07817883, a second-generation, orally bioavailable, SARS-CoV-2 main protease inhibitor with improved metabolic stability versus nirmatrelvir, the antiviral component of the ritonavir-boosted therapy Paxlovid. We demonstrate the in vitro pan-human coronavirus antiviral activity and off-target selectivity profile of PF-07817883. PF-07817883 also demonstrated oral efficacy in a mouse-adapted SARS-CoV-2 model at plasma concentrations equivalent to nirmatrelvir. The preclinical in vivo pharmacokinetics and metabolism studies in human matrices are suggestive of improved oral pharmacokinetics for PF-07817883 in humans, relative to nirmatrelvir. In vitro inhibition/induction studies against major human drug metabolizing enzymes/transporters suggest a low potential for perpetrator drug-drug interactions upon single-agent use of PF-07817883.

3.
Data Brief ; 53: 110184, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38406255

ABSTRACT

Road traffic accidents constitute the primary cause of fatalities associated with injuries and engender substantial economic ramifications for affected individuals, their families, and entire nations. The Sultanate of Oman, like other countries, suffers from traffic accident injuries and traffic congestion. The accident rate for the period 2021 was recorded as one accident every six hours. Despite a 70% increase in total number of vehicles and an 81% rise in licensed drivers between 2012 and 2019, data on traffic accidents demonstrate an improving trend with a notable 55% decline in crash fatalities. However, it is important to recognize that road traffic accidents in Oman encompass not only social issues but also pose a significant economic burden, resulting in substantial financial costs for the nation. Notwithstanding, it was discovered that more than 50% of fatal crashes in Oman were primarily caused by excessive speeding. The main goal of this research is to analysis the causes and trends of traffic accidents at the national level in the Sultanate of Oman. Data analysis reveals speed as the primary cause of traffic accidents in Oman, with Muscat and Dhofar registering the highest accident rates. In addition, the distribution of deaths and injuries resulting from accidents varies according to Gender and nationality. According to the road accident scenario analysis in the state, more traffic accidents occurred in males than females. Traffic accidents have witnessed a notable decline over the past decade, attributable to the diligent efforts and interventions implemented by the Royal Oman Police.

4.
Materials (Basel) ; 15(9)2022 Apr 29.
Article in English | MEDLINE | ID: mdl-35591538

ABSTRACT

The effect of high temperatures on rock's thermophysical and mechanical properties is critical to the design of underground geotechnical applications. The current work investigates the impact of temperature on rhyolitic turf rock's physical and mechanical properties. Intact cylindrical core rock samples were heated to different temperatures (200, 400, 600, and 800 °C). The uniaxial compressive strength (UCS) and elastic modulus of unheated and heated samples were determined as important mechanical properties. In addition, the effect of temperature on the physical properties of rhyolite rock (density, color, and absorption) was investigated in conjunction with its microstructural properties. The hardening of the rhyolitic rock samples was observed below 600 °C, at which point the UCS and elastic modulus decreased to 78.0% and 75.9%, respectively, at 800 °C. The results also show that heating does not significantly affect the density and volume of permeable pore space, but a color change can be observed at 400 °C and above. A microscopic analysis shows the change in microstructural properties of rhyolite rock after heating to 600 °C. Furthermore, the SEM observations of heated materials show structural particle displacements and microcracking, leading to apparent surface cracks.

5.
Preprint in English | bioRxiv | ID: ppbiorxiv-486975

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic resulting in millions of deaths worldwide. Increasingly contagious variants of concern (VoC) have fueled recurring global infection waves. A major question is the relative severity of disease caused by the previous and currently circulating variants of SARS-CoV-2. In this study, we evaluated the pathogenesis of SARS-CoV-2 variants in human ACE-2-expressing (K18-hACE2) mice. Eight-week-old K18-hACE2 mice were inoculated intranasally with a representative virus from the original B.1 lineage, or the emerging B.1.1.7 (alpha), B.1.351 (beta), B.1.617.2 (delta) or B.1.1.529 (omicron) lineages. We also infected a group of mice with the mouse-adapted SARS-CoV-2 (MA10). Our results demonstrate that B.1.1.7, B.1.351 and B.1.617.2 viruses are significantly more lethal than B.1 strain in K18-hACE2 mice. Infection with B.1.1.7, B.1.351 and B.1.617.2 variants resulted in significantly higher virus titers in the lungs and brain of mice compared to the B.1 virus. Interestingly, mice infected with the B.1.1.529 variant exhibited less severe clinical signs and high survival rate. We found that B.1.1.529 replication was significantly lower in the lungs and brain of infected mice in comparison to other VoC. Transcription levels of cytokines and chemokines in the lungs of the B.1.1.529-infected mice were significantly less when compared to those challenged with the B.1.1.7 virus. Together, our data provide insights into the pathogenesis of the previous and circulating SARS-CoV-2 VoC in mice.

6.
Pathogens ; 11(2)2022 Feb 17.
Article in English | MEDLINE | ID: mdl-35215199

ABSTRACT

Transgenic mice expressing human angiotensin-converting enzyme 2 under the cytokeratin 18 promoter (K18-hACE2) have been extensively used to investigate the pathogenesis and tissue tropism of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. Neuroinvasion and the replication of SARS-CoV-2 within the central nervous system (CNS) of K18-hACE2 mice is associated with increased mortality; although, the mechanisms by which this occurs remain unclear. In this study, we generated primary neuronal cultures from K18-hACE2 mice to investigate the effects of a SARS-CoV-2 infection. We also evaluated the immunological response to SARS-CoV-2 infection in the CNS of K18-hACE2 mice and mouse neuronal cultures. Our data show that neuronal cultures obtained from K18-hACE2 mice are permissive to SARS-CoV-2 infection and support productive virus replication. Furthermore, SARS-CoV-2 infection upregulated the expression of genes involved in innate immunity and inflammation, including IFN-α, ISG-15, CXCL10, CCL2, IL-6 and TNF-α, in the neurons and mouse brains. In addition, we found that SARS-CoV-2 infection of neurons and mouse brains activates the ZBP1/pMLKL-regulated necroptosis pathway. Together, our data provide insights into the neuropathogenesis of SARS-CoV-2 infection in K18-hACE2 mice.

7.
Preprint in English | bioRxiv | ID: ppbiorxiv-476644

ABSTRACT

New variants of SARS-CoV-2 with potential for enhanced transmission, replication, and immune evasion capabilities continue to emerge causing reduced vaccine efficacy and/or treatment failure. As of January 2021, the WHO has defined five variants of concern (VOC): B.1.1.7 (Alpha, ), B.1.351 (Beta, {beta}), P.1 (Gamma, {gamma}), B.1.617.2 (Delta, {delta}), and B.1.1.529 (Omicron, o). To provide a therapeutic option for the treatment of COVID-19 and variants, Nirmatrelvir, the antiviral component of PAXLOVID, an oral outpatient treatment recently authorized for conditional or emergency use treatment of COVID-19, was developed to inhibit SARS-CoV-2 replication. Nirmatrelvir (PF-07321332) is a specific inhibitor of coronavirus main protease (Mpro, also referred to as 3CLpro), with potent antiviral activity against several human coronaviruses, including SARS-CoV-2, SARS-CoV, and MERS (Owen et al, Science 2021. doi: 10.1126/science.abl4784). Here, we evaluated PF-07321332 against the five SARS-CoV-2 VOC (, {beta}, {gamma}, {delta},, o) and two Variants of Interest or VOI, C.37 ({lambda}) and B.1.621 (), using qRT-PCR in VeroE6 cells lacking the P-glycoprotein (Pgp) multidrug transporter gene (VeroE6 P-gp knockout cells). Nirmatrelvir potently inhibited USA-WA1/2020 strain, and , {beta}, {gamma}, {lambda}, {delta}, , and o variants in VeroE6 P-gp knockout cells with mean EC50 values 38.0 nM, 41.0 nM, 127.2 nM, 24.9 nM, 21.2 nM, 15.9 nM, 25.7 nM and 16.2 nM, respectively. Sequence analysis of the Mpro encoded by the variants showed ~100% identity of active site amino acid sequences, reflecting the essential role of Mpro during viral replication leading to ability of Nirmatrelvir to exhibit potent activity across all the variants.

8.
Preprint in English | bioRxiv | ID: ppbiorxiv-462373

ABSTRACT

The emergence of new severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants of concern poses a major threat to the public health due to possible enhanced virulence, transmissibility and immune escape. These variants may also adapt to new hosts in part through mutations in the spike protein. In this study, we evaluated the infectivity and pathogenicity of SARS-CoV-2 variants of concern in wild-type C57BL/6 mice. Six-week-old mice were inoculated intranasally with a representative virus from the original B.1 lineage or emerging B.1.1.7 and B.1.351 lineages. We also infected a group of mice with a mouse-adapted SARS-CoV-2 (MA10). Viral load and mRNA levels of multiple cytokines and chemokines were analyzed in the lung tissues on day 3 after infection. Our data show that unlike the B.1 virus, the B.1.1.7 and B.1.351 viruses are capable of infecting C57BL/6 mice and replicating at high concentrations in the lungs. The B.1.351 virus replicated to higher titers in the lungs compared to the B.1.1.7 and MA10 viruses. The levels of cytokines (IL-6, TNF-, IL-1{beta}) and chemokine (CCL2) were upregulated in response to the B.1.1.7 and B.1.351 infection in the lungs. Overall, these data indicate a greater potential for infectivity and adaptation to new hosts by emerging SARS-CoV-2 variants.

9.
Molecules ; 26(14)2021 Jul 16.
Article in English | MEDLINE | ID: mdl-34299596

ABSTRACT

Zika virus (ZIKV) represents a re-emerging threat to global health due to its association with congenital birth defects. ZIKV NS2B-NS3 protease is crucial for virus replication by cleaving viral polyprotein at various junctions to release viral proteins and cause cytotoxic effects in ZIKV-infected cells. This study characterized the inhibitory effects of doxycycline against ZIKV NS2B-NS3 protease and viral replication in human skin cells. The in silico data showed that doxycycline binds to the active site of ZIKV protease at a low docking energy (-7.8 Kcal/mol) via four hydrogen bonds with the protease residues TYR1130, SER1135, GLY1151, and ASP83. Doxycycline efficiently inhibited viral NS2B-NS3 protease at average human temperature (37 °C) and human temperature with a high fever during virus infection (40 °C). Interestingly, doxycycline showed a higher inhibitory effect at 40 °C (IC50 = 5.3 µM) compared to 37 °C (9.9 µM). The virus replication was considerably reduced by increasing the concentration of doxycycline. An approximately 50% reduction in virus replication was observed at 20 µM of doxycycline. Treatment with 20 µM of doxycycline reduced the cytopathic effects (CPE), and the 40 µM of doxycycline almost eliminated the CPE of human skin cells. This study showed that doxycycline binds to the ZIKV protease and inhibits its catalytic activity at a low micro-molecular concentration range. Treatment of human skin fibroblast with doxycycline eliminated ZIKV infection and protected the cells against the cytopathic effects of the infection.


Subject(s)
Doxycycline/pharmacology , Fibroblasts/metabolism , Skin/metabolism , Viral Nonstructural Proteins/antagonists & inhibitors , Viral Proteins/antagonists & inhibitors , Virus Replication/drug effects , Zika Virus/physiology , Animals , Chlorocebus aethiops , Doxycycline/chemistry , Fibroblasts/virology , Humans , Serine Endopeptidases/chemistry , Serine Endopeptidases/metabolism , Skin/virology , Vero Cells , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/metabolism , Viral Proteins/chemistry , Viral Proteins/metabolism , Zika Virus/chemistry
10.
Viruses ; 13(1)2021 Jan 19.
Article in English | MEDLINE | ID: mdl-33477869

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection can cause neurological disease in humans, but little is known about the pathogenesis of SARS-CoV-2 infection in the central nervous system (CNS). Herein, using K18-hACE2 mice, we demonstrate that SARS-CoV-2 neuroinvasion and encephalitis is associated with mortality in these mice. Intranasal infection of K18-hACE2 mice with 105 plaque-forming units of SARS-CoV-2 resulted in 100% mortality by day 6 after infection. The highest virus titers in the lungs were observed on day 3 and declined on days 5 and 6 after infection. By contrast, very high levels of infectious virus were uniformly detected in the brains of all the animals on days 5 and 6. Onset of severe disease in infected mice correlated with peak viral levels in the brain. SARS-CoV-2-infected mice exhibited encephalitis hallmarks characterized by production of cytokines and chemokines, leukocyte infiltration, hemorrhage and neuronal cell death. SARS-CoV-2 was also found to productively infect cells within the nasal turbinate, eye and olfactory bulb, suggesting SARS-CoV-2 entry into the brain by this route after intranasal infection. Our data indicate that direct infection of CNS cells together with the induced inflammatory response in the brain resulted in the severe disease observed in SARS-CoV-2-infected K18-hACE2 mice.


Subject(s)
Brain/virology , COVID-19/pathology , Encephalitis, Viral/pathology , Lung/virology , SARS-CoV-2/metabolism , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , Brain/pathology , COVID-19/mortality , Cytokines/blood , Disease Models, Animal , Encephalitis, Viral/virology , Lung/pathology , Mice , Mice, Transgenic , Viral Load
11.
Mol Biotechnol ; 63(3): 240-248, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33464543

ABSTRACT

The global public health has been compromised since the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) emerged in late December 2019. There are no specific antiviral drugs available to combat SARS-CoV-2 infection. Besides the rapid dissemination of SARS-CoV-2, several variants have been identified with a potential epidemiologic and pathogenic variation. This fact has forced antiviral drug development strategies to stay innovative, including new drug discovery protocols, combining drugs, and establishing new drug classes. Thus, developing novel screening methods and direct-targeting viral enzymes could be an attractive strategy to combat SARS-CoV-2 infection. In this study, we designed, optimized, and validated a cell-based assay protocol for high-throughput screening (HTS) antiviral drug inhibitors against main viral protease (3CLpro). We applied the split-GFP complementation to develop GFP-split-3CLpro HTS system. The system consists of GFP-based reporters that become fluorescent upon cleavage by SARS-CoV-2 protease 3CLpro. We generated a stable GFP-split-3CLpro HTS system valid to screen large drug libraries for inhibitors to SARS-CoV-2 main protease in the bio-safety level 2 laboratory, providing real-time antiviral activity of the tested compounds. Using this assay, we identified a new class of viral protease inhibitors derived from quinazoline compounds that worth further in vitro and in vivo validation.


Subject(s)
Antiviral Agents , Coronavirus 3C Proteases/antagonists & inhibitors , High-Throughput Screening Assays/methods , SARS-CoV-2/drug effects , COVID-19/virology , Coronavirus 3C Proteases/chemistry , Coronavirus 3C Proteases/metabolism , Drug Development , Green Fluorescent Proteins/chemistry , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , HEK293 Cells , Humans , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Small Molecule Libraries
12.
Pediatr Allergy Immunol ; 32(1): 17-22, 2021 01.
Article in English | MEDLINE | ID: mdl-32897642

ABSTRACT

Multisystem inflammatory syndrome in children (MIS-C) during the COVID-19 pandemic raised a global alert from the Centers for Disease Control and Prevention's Health Alert Network. The main manifestations of MIS-C (also known as pediatric MIS (PMIS)) in the setting of a severe inflammatory state include fever, diarrhea, shock, and variable presence of rash, conjunctivitis, extremity edema, and mucous membrane changes. In some cases, these symptoms progressed to multi-organ failure. The low percentage of children with asymptomatic cases compared with mild illness and moderate illness could be correlated with the rare cases of MIS-C. One potential explanation for the progression to severe MIS-C disease despite the presence of readily detectable anti-SARS-CoV-2 antibodies could be due to the potential role of antibody-dependent enhancement (ADE). We reason that the incidence of the ADE phenomenon whereby the pathogen-specific antibodies can promote pathology should be considered in vaccine development against SARS-CoV-2.


Subject(s)
COVID-19/epidemiology , Systemic Inflammatory Response Syndrome/epidemiology , Adolescent , Antibodies, Viral/immunology , Antibody-Dependent Enhancement/immunology , COVID-19/immunology , Child , Child, Preschool , Conjunctivitis/epidemiology , Diarrhea/epidemiology , Exanthema/epidemiology , Humans , Infant , Macrophage Activation/immunology , Pandemics , SARS-CoV-2/immunology , Severity of Illness Index , Systemic Inflammatory Response Syndrome/immunology , Young Adult
13.
Preprint in English | bioRxiv | ID: ppbiorxiv-422714

ABSTRACT

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection can cause neurological disease in humans, but little is known about the pathogenesis of SARS-CoV-2 infection in the central nervous system. Herein, using K18-hACE2 mice, we demonstrate that SARS-CoV-2 neuroinvasion and encephalitis is associated with mortality in these mice. Intranasal infection of K18-hACE2 mice with 105 plaque-forming units of SARS-CoV-2 resulted in 100% mortality by day 6 after infection. The highest virus titers in the lungs were observed at day 3 and declined at days 5 and 6 after infection. In contrast, very high levels of infectious virus were uniformly detected in the brains of all the animals at days 5 and 6. Onset of severe disease in infected mice correlated with peak viral levels in the brain. SARS-CoV-2-infected mice exhibited encephalitis hallmarks characterized by production of cytokines and chemokines, leukocyte infiltration, hemorrhage and neuronal cell death. SARS-CoV-2 was also found to productively infect cells within the nasal turbinate, eye and olfactory bulb, suggesting SARS-CoV-2 entry into the brain by this route after intranasal infection. Our data indicate that direct infection of CNS cells together with the induced inflammatory response in the brain resulted in the severe disease observed in SARS-CoV-2-infected K18-hACE2 mice.

14.
Pathogens ; 9(7)2020 Jul 06.
Article in English | MEDLINE | ID: mdl-32640525

ABSTRACT

In the absence of therapeutic interventions, and a possible vaccine candidate, the spread of COVID-19 disease and associated fatalities are on the rise. The high mutation frequency in the genomic material of these viruses supports their ability to adapt to new environments, resulting in an efficient alteration in tissue tropism and host range. Therefore, the coronavirus' health threats could be relevant for the long-term. The epidemiological data indicate that age, sex, and cardio-metabolic disease have a significant impact on the spread and severity of COVID-19. In this review, we highlight recent updates on the pathogenesis of SARS-CoV-2 among men and women, including children. We also discuss the role of the cellular receptors and coreceptors used by the virus to enter host cells on differential infection among men, women, and cardio-metabolic patients.

15.
Virology ; 547: 7-11, 2020 08.
Article in English | MEDLINE | ID: mdl-32442105

ABSTRACT

SARS-COV-2 has recently emerged as a new public health threat. Herein, we report that the FDA-approved drug, auranofin, inhibits SARS-COV-2 replication in human cells at low micro molar concentration. Treatment of cells with auranofin resulted in a 95% reduction in the viral RNA at 48 h after infection. Auranofin treatment dramatically reduced the expression of SARS-COV-2-induced cytokines in human cells. These data indicate that auranofin could be a useful drug to limit SARS-CoV-2 infection and associated lung injury due to its antiviral, anti-inflammatory and anti-reactive oxygen species (ROS) properties. Further animal studies are warranted to evaluate the safety and efficacy of auranofin for the management of SARS-COV-2 associated disease.


Subject(s)
Auranofin/pharmacology , Betacoronavirus/drug effects , Virus Replication/drug effects , Antiviral Agents/pharmacology , Betacoronavirus/physiology , COVID-19 , Cell Line , Coronavirus Infections , Cytokines , Drug Evaluation, Preclinical , Gold , Humans , Inflammation , Pandemics , Pneumonia, Viral , SARS-CoV-2
16.
Mol Biotechnol ; 62(5): 289-296, 2020 May.
Article in English | MEDLINE | ID: mdl-32185600

ABSTRACT

Pasteurella multocida is the main cause of haemorrhagic septicaemia (HS) outbreak in livestock, such as cattle and buffaloes. Conventional vaccines such as alum-precipitated or oil-adjuvant broth bacterins were injected subcutaneously to provide protection against HS. However, the immunity developed is only for short term and needed to be administered frequently. In our previous study, a short gene fragment from Pasteurella multocida serotype B was obtained via shotgun cloning technique and later was cloned into bacterial expression system. pQE32-ABA392 was found to possess immunogenic activity towards HS when tested in vivo in rat model. In this study, the targeted gene fragment of ABA392 was sub-cloned into a DNA expression vector pVAX1 and named as pVAX1-ABA392. The new recombinant vaccine was stable and expressed on mammalian cell lines. Serum sample collected from a group of vaccinated rats for ELISA test shows that the antibody in immunized rats was present at high titer and can be tested as a vaccine candidate with challenge in further studies. This successful recombinant vaccine is immunogenic and potentially could be used as vaccine in future against HS.


Subject(s)
DNA, Bacterial/genetics , Hemorrhagic Septicemia/microbiology , Pasteurella Infections/prevention & control , Pasteurella multocida/genetics , Vaccines, DNA/administration & dosage , Animals , Cloning, Molecular , DNA, Bacterial/immunology , Disease Models, Animal , Female , Genetic Vectors/administration & dosage , Genetic Vectors/immunology , Hemorrhagic Septicemia/prevention & control , Pasteurella multocida/immunology , Plasmids/genetics , Rats , Sequence Analysis, DNA , Vaccination , Vaccines, DNA/immunology
17.
J Autoimmun ; 109: 102433, 2020 05.
Article in English | MEDLINE | ID: mdl-32113704

ABSTRACT

Coronavirus disease (COVID-19) is caused by SARS-COV2 and represents the causative agent of a potentially fatal disease that is of great global public health concern. Based on the large number of infected people that were exposed to the wet animal market in Wuhan City, China, it is suggested that this is likely the zoonotic origin of COVID-19. Person-to-person transmission of COVID-19 infection led to the isolation of patients that were subsequently administered a variety of treatments. Extensive measures to reduce person-to-person transmission of COVID-19 have been implemented to control the current outbreak. Special attention and efforts to protect or reduce transmission should be applied in susceptible populations including children, health care providers, and elderly people. In this review, we highlights the symptoms, epidemiology, transmission, pathogenesis, phylogenetic analysis and future directions to control the spread of this fatal disease.


Subject(s)
Betacoronavirus/classification , Betacoronavirus/pathogenicity , Coronavirus Infections/epidemiology , Coronavirus Infections/transmission , Pneumonia, Viral/epidemiology , Pneumonia, Viral/transmission , Animals , COVID-19 , Coronavirus Infections/prevention & control , Humans , Pandemics/prevention & control , Phylogeny , Pneumonia, Viral/prevention & control , Public Health , SARS-CoV-2 , Zoonoses/epidemiology , Zoonoses/virology
18.
Viruses ; 12(1)2019 12 19.
Article in English | MEDLINE | ID: mdl-31861621

ABSTRACT

West Nile virus (WNV) is a flavivirus that has disseminated globally as a significant cause of viral encephalitis in humans. MircoRNA-155 (miR-155) regulates various aspects of innate and adaptive immune responses. We previously reported that WNV infection induces upregulation of miR-155 in mice brains. In the current study, we demonstrate the critical role of miR-155 in restricting the pathogenesis of WNV infection in mice. Compared to wild-type (WT) mice, miR-155 knockout mice exhibited significantly higher morbidity and mortality after infection with either a lethal strain, WNV NY99, or a non-lethal strain, WNV Eg101. Increased mortality in miR-155-/- mice was associated with significantly high WNV burden in the serum and brains. Protein levels of interferon (IFN)-α in the serum and brains were higher in miR-155-/- mice. However, miR-155-/- mice exhibited significantly lower protein levels of anti-viral interleukin (IL)-1ß, IL-12, IL-6, IL-15, and GM-CSF despite the high viral load. Primary mouse cells lacking miR-155 were more susceptible to infection with WNV compared to cells derived from WT mice. Besides, overexpression of miR-155 in human neuronal cells modulated anti-viral cytokine response and resulted in significantly lower WNV replication. These data collectively indicate that miR-155 restricts WNV production in mouse and human cells and protects against lethal WNV infection in mice.


Subject(s)
Gene Expression Regulation , Host-Pathogen Interactions/genetics , MicroRNAs/genetics , West Nile Fever/genetics , West Nile Fever/virology , West Nile virus/physiology , Animals , Cell Line , Cytokines/metabolism , Disease Models, Animal , Host-Pathogen Interactions/immunology , Humans , Inflammation Mediators/metabolism , Mice , Mice, Knockout , Viral Load , Virus Replication , West Nile Fever/immunology , West Nile Fever/pathology
19.
Front Microbiol ; 10: 2089, 2019.
Article in English | MEDLINE | ID: mdl-31572318

ABSTRACT

West Nile virus (WNV), a neurotropic flavivirus, is the leading cause of viral encephalitis in the United States. Recently, Zika virus (ZIKV) infections have caused serious neurological diseases and birth defects, specifically Guillain-Barrè syndrome and microcephaly. Z-DNA binding protein 1 (ZBP1) is a cytoplasmic sensor that that has been shown to play a significant role in initiating a robust immune response. We previously reported that WNV and ZIKV infections induce dramatic up-regulation of ZBP1 in mouse brains as well as in infected primary mouse cells. Herein, we show the critical role of ZBP1 in restricting the pathogenesis of WNV and ZIKV infections. Deletion of ZBP1 resulted in significantly higher morbidity and mortality after infection with a pathogenic WNV NY99 strain in mice. No mortality was observed in wild-type (WT) mice infected with the non-pathogenic WNV strain, Eg101. Interestingly, infection of ZBP1-/- mice with WNV Eg101 was lethal resulting in 100% mortality, suggesting that ZBP1 is required for survival after WNV infection. Viremia and brain viral load were significantly higher in ZBP1-/- mice compared to WT mice. In addition, protein levels of interferon (IFN)-α, and inflammatory cytokines and chemokines were significantly higher in the serum and brains of infected ZBP1-/- mice compared to the WT mice. Primary mouse cortical neurons and mouse embryonic fibroblasts (MEFs) derived from ZBP1-/- mice produced higher virus titers compared to WT cells after infection with WNV NY99 and WNV Eg101. Similarly, neurons and MEFs lacking ZBP1 exhibited significantly enhanced replication of PRVABC59 (Asian) and MR766 (African) ZIKV compared to WT cells. The knockout of ZBP1 function in MEFs inhibited ZBP1-dependent virus-induced cell death. In conclusion, these data reveal that ZBP1 restricts WNV and ZIKV production in mouse cells and is required for survival of a peripheral WNV infection in mice.

20.
Pathogens ; 8(3)2019 Sep 12.
Article in English | MEDLINE | ID: mdl-31547236

ABSTRACT

Flavivirus replication in host cells requires the formation of replication and assembly complexes on the cytoplasmic side of the endoplasmic reticulum (ER) membrane. These complexes consist of an ER membrane, viral proteins, and host proteins. Genome-wide investigations have identified a number of ER multiprotein complexes as vital factors for flavivirus replication. The detailed mechanisms of the role of ER complexes in flavivirus replication are still largely elusive. This review highlights the fact that the ER multiprotein complexes are crucial for the formation of flavivirus replication and assembly complexes, and the ER complexes could be considered as a target for developing successful broad-spectrum anti-flavivirus drugs.

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