scholarly journals Pathogenesis of COVID-19-induced ARDS: implications for an ageing population

2020 ◽  
Vol 56 (3) ◽  
pp. 2002049 ◽  
Author(s):  
Manuel A. Torres Acosta ◽  
Benjamin D. Singer

The coronavirus disease 2019 (COVID-19) pandemic has elicited a swift response by the scientific community to elucidate the pathogenesis of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2)-induced lung injury and develop effective therapeutics. Clinical data indicate that severe COVID-19 most commonly manifests as viral pneumonia-induced acute respiratory distress syndrome (ARDS), a clinical entity mechanistically understood best in the context of influenza A virus-induced pneumonia. Similar to influenza, advanced age has emerged as the leading host risk factor for developing severe COVID-19. In this review we connect the current understanding of the SARS-CoV-2 replication cycle and host response to the clinical presentation of COVID-19, borrowing concepts from influenza A virus-induced ARDS pathogenesis and discussing how these ideas inform our evolving understanding of COVID-19-induced ARDS. We also consider important differences between COVID-19 and influenza, mainly the protean clinical presentation and associated lymphopenia of COVID-19, the contrasting role of interferon-γ in mediating the host immune response to these viruses, and the tropism for vascular endothelial cells of SARS-CoV-2, commenting on the potential limitations of influenza as a model for COVID-19. Finally, we explore hallmarks of ageing that could explain the association between advanced age and susceptibility to severe COVID-19.

2018 ◽  
Vol 17 (10) ◽  
pp. 728-735 ◽  
Author(s):  
Xiaolin Deng ◽  
Yangmei Xie ◽  
Yinghui Chen

Background & Objective: Epilepsy is a common and serious chronic neurological disorder that is mainly treated with antiepileptic drugs. Although current antiepileptic drugs used in clinical practice have advanced to the third generation, approximately one-third of patients are refractory to these treatments. More efficacious treatments for refractory epilepsy are therefore needed. A better understanding of the mechanism underlying refractory epilepsy is likely to facilitate the development of a more effective therapy. The abnormal expression and/or dysfunction of efflux transporters, particularly ABC transporters, might contribute to certain cases of refractory epilepsy. Inflammation in the brain has recently been shown to regulate the expression and/or function of ABC transporters in the cerebral vascular endothelial cells and glia of the blood-brain barrier by activating intracellular signalling pathways. Conclusion: Therefore, in this review, we will briefly summarize recent research advances regarding the possible role of neuroinflammation in regulating ABC transporter expression in epilepsy.


2021 ◽  
Vol 22 (5) ◽  
pp. 2409
Author(s):  
Anastasia A. Bizyaeva ◽  
Dmitry A. Bunin ◽  
Valeria L. Moiseenko ◽  
Alexandra S. Gambaryan ◽  
Sonja Balk ◽  
...  

Nucleic acid aptamers are generally accepted as promising elements for the specific and high-affinity binding of various biomolecules. It has been shown for a number of aptamers that the complexes with several related proteins may possess a similar affinity. An outstanding example is the G-quadruplex DNA aptamer RHA0385, which binds to the hemagglutinins of various influenza A virus strains. These hemagglutinins have homologous tertiary structures but moderate-to-low amino acid sequence identities. Here, the experiment was inverted, targeting the same protein using a set of related, parallel G-quadruplexes. The 5′- and 3′-flanking sequences of RHA0385 were truncated to yield parallel G-quadruplex with three propeller loops that were 7, 1, and 1 nucleotides in length. Next, a set of minimal, parallel G-quadruplexes with three single-nucleotide loops was tested. These G-quadruplexes were characterized both structurally and functionally. All parallel G-quadruplexes had affinities for both recombinant hemagglutinin and influenza virions. In summary, the parallel G-quadruplex represents a minimal core structure with functional activity that binds influenza A hemagglutinin. The flanking sequences and loops represent additional features that can be used to modulate the affinity. Thus, the RHA0385–hemagglutinin complex serves as an excellent example of the hypothesis of a core structure that is decorated with additional recognizing elements capable of improving the binding properties of the aptamer.


2021 ◽  
Vol 22 (6) ◽  
pp. 2804
Author(s):  
Yasuo Yoshitomi ◽  
Takayuki Ikeda ◽  
Hidehito Saito-Takatsuji ◽  
Hideto Yonekura

Blood vessels are essential for the formation and maintenance of almost all functional tissues. They play fundamental roles in the supply of oxygen and nutrition, as well as development and morphogenesis. Vascular endothelial cells are the main factor in blood vessel formation. Recently, research findings showed heterogeneity in vascular endothelial cells in different tissue/organs. Endothelial cells alter their gene expressions depending on their cell fate or angiogenic states of vascular development in normal and pathological processes. Studies on gene regulation in endothelial cells demonstrated that the activator protein 1 (AP-1) transcription factors are implicated in angiogenesis and vascular development. In particular, it has been revealed that JunB (a member of the AP-1 transcription factor family) is transiently induced in endothelial cells at the angiogenic frontier and controls them on tip cells specification during vascular development. Moreover, JunB plays a role in tissue-specific vascular maturation processes during neurovascular interaction in mouse embryonic skin and retina vasculatures. Thus, JunB appears to be a new angiogenic factor that induces endothelial cell migration and sprouting particularly in neurovascular interaction during vascular development. In this review, we discuss the recently identified role of JunB in endothelial cells and blood vessel formation.


2016 ◽  
Vol 8 (17) ◽  
pp. 2017-2031 ◽  
Author(s):  
Simona Panella ◽  
Maria Elena Marcocci ◽  
Ignacio Celestino ◽  
Sergio Valente ◽  
Clemens Zwergel ◽  
...  

2021 ◽  
Author(s):  
Jing Wu ◽  
Jiaqi Gu ◽  
Li Shen ◽  
Xiaonan Jia ◽  
Yiqian Yin ◽  
...  

Influenza A virus (IAV) is a crucial cause of respiratory infections in humans worldwide. Therefore, studies should clarify adaptation mechanisms of IAV and critical factors of the viral pathogenesis in human hosts. GTPases of the Rab family are the largest branch of the Ras-like small GTPase superfamily, and they regulate almost every step during vesicle-mediated trafficking. Evidence has shown that Rab proteins participate in the lifecycle of IAV. In this mini-review, we outline the regulatory mechanisms of different Rab proteins in the lifecycle of IAV. Understanding the role of Rab proteins in IAV infections is important to develop broad-spectrum host-targeted antiviral strategies.


2021 ◽  
Author(s):  
Ee-Hong Tam ◽  
Yen-Chin Liu ◽  
Chian-Huey Woung ◽  
Helene Minyi Liu ◽  
Guan-Hong Wu ◽  
...  

The NS1 protein of the influenza A virus plays a critical role in regulating several biological processes in cells, including the type I interferon (IFN) response. We previously profiled the cellular factors that interact with the NS1 protein of influenza A virus and found that the NS1 protein interacts with proteins involved in RNA splicing/processing, cell cycle regulation, and protein targeting processes, including 14-3-3ε. Since 14-3-3ε plays an important role in RIG-I translocation to MAVS to activate type I IFN expression, the interaction of the NS1 and 14-3-3ε proteins may prevent the RIG-I-mediated IFN response. In this study, we confirmed that the 14-3-3ε protein interacts with the N-terminal domain of the NS1 protein and that the NS1 protein inhibits RIG-I-mediated IFN-β promoter activation in 14-3-3ε-overexpressing cells. In addition, our results showed that knocking down 14-3-3ε can reduce IFN-β expression elicited by influenza A virus and enhance viral replication. Furthermore, we found that threonine in the 49 th amino acid position of the NS1 protein plays a role in the interaction with 14-3-3ε. Influenza A virus expressing C-terminus-truncated NS1 with T49A mutation dramatically increases IFN-β mRNA in infected cells and causes slower replication than that of virus without the T-to-A mutation. Collectively, this study demonstrates that 14-3-3ε is involved in influenza A virus-initiated IFN-β expression and that the interaction of the NS1 protein and 14-3-3ε may be one of the mechanisms for inhibiting type I IFN activation during influenza A virus infection. IMPORTANCE Influenza A virus is an important human pathogen causing severe respiratory disease. The virus has evolved several strategies to dysregulate the innate immune response and facilitate its replication. We demonstrate that the NS1 protein of influenza A virus interacts with the cellular chaperone protein 14-3-3ε, which plays a critical role in RIG-I translocation that induces type I IFN expression, and that NS1 protein prevents RIG-I translocation to mitochondrial membrane. The interaction site for 14-3-3ε is the RNA-binding domain (RBD) of the NS1 protein. Therefore, this research elucidates a novel mechanism by which the NS1 RBD mediates IFN-β suppression to facilitate influenza A viral replication. Additionally, the findings reveal the antiviral role of 14-3-3ε during influenza A virus infection.


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