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1.
Journal of the American Society of Nephrology ; 33:72, 2022.
Article in English | EMBASE | ID: covidwho-2125201

ABSTRACT

Background: AKI is a common complication of COVID-19. The peripheral blood molecular signatures are unknown and could unveil potential therapeutic targets. Method(s): We enrolled a prospective patient cohort of 283 patients with COVID-19 (Mar 24-Aug 26, 2020), with blood samples from Mount Sinai Biobank. We determined AKI severity using KDIGO criteria on admission parameters. 31 patients with severe AKI (AKI 2-3) were defined as cases. We then performed bulk peripheral RNA sequencing and fit a multivariate linear regression model adjusting for key covariates. We also performed cell-type deconvolution following to adjust for neutrophils, and whole blood cells. We considered a significant p-value (0.05) after Bonferroni correction and then used ingenuity pathway analysis (IPA) to analyze differentially expressed genes. Result(s): Patients who developed AKI were significantly older (67 vs. 60 yrs.) and had a greater prevalence of type 2 diabetes (37% vs 20%), and chronic kidney disease (20% vs 4%) vs. controls. Of the 18539 genes in the analysis, 1597 were upregulated and 1267 were downregulated after Bonferroni correction. Top canonical pathways (Fig 1) showed significantly downregulated genes including EIF2, eIF4, and p70S6K via activation of ATF6, a marker of ER stress. Potential mechanisms displayed by our analyses include upregulation of the NF-KB inhibitor and IL6 pathways. Genes involved in oxidative Phosphorylation and mitochondrial dysfunction were heavily downregulated and there was upregulation of markers of kidney cell necrosis. In contrast, upregulated genes CRK and TIMP2 have been previously implicated in kidney injury and progression. Downregulated mTOR pathway is responsible for the activation of the ER stress response via the eIF2/4 complex which is also supported by our finding of upregulated NRF2- transcriptional pathway. Conclusion(s): Transcriptomic analysis of AKI in COVID-19 revealed evidence of mitochondrial dysfunction driven by ER stress and immune-mediated pathways. Addressing these pathways could aide development of targeted therapies. (Figure Presented).

2.
Diabetologia ; 2022 Nov 19.
Article in English | MEDLINE | ID: covidwho-2128530

ABSTRACT

AIMS/HYPOTHESIS: Diabetes is characterised by progressive loss of functional pancreatic beta cells. None of the therapeutic agents used to treat diabetes arrest this process; preventing beta cell loss remains a major unmet need. We have previously shown that serum from eight young healthy male participants who exercised for 8 weeks protected human islets and insulin-producing EndoC-ßH1 cells from apoptosis induced by proinflammatory cytokines or the endoplasmic reticulum (ER) stressor thapsigargin. Whether this protective effect is influenced by sex, age, training modality, ancestry or diabetes is unknown. METHODS: We enrolled 82 individuals, male or female, non-diabetic or diabetic, from different origins, in different supervised training protocols for 8-12 weeks (including training at home during the COVID-19 pandemic). EndoC-ßH1 cells were treated with 'exercised' serum or with the exerkine clusterin to ascertain cytoprotection from ER stress. RESULTS: The exercise interventions were effective and improved [Formula: see text] values in both younger and older, non-obese and obese, non-diabetic and diabetic participants. Serum obtained after training conferred significant beta cell protection (28% to 35% protection after 4 and 8 weeks of training, respectively) from severe ER stress-induced apoptosis. Cytoprotection was not affected by the type of exercise training or participant age, sex, BMI or ancestry, and persisted for up to 2 months after the end of the training programme. Serum from exercised participants with type 1 or type 2 diabetes was similarly protective. Clusterin reproduced the beneficial effects of exercised sera. CONCLUSIONS/INTERPRETATION: These data uncover the unexpected potential to preserve beta cell health by exercise training, opening a new avenue to prevent or slow diabetes progression through humoral muscle-beta cell crosstalk.

3.
Res Vet Sci ; 152: 236-244, 2022 Dec 20.
Article in English | MEDLINE | ID: covidwho-2069657

ABSTRACT

Porcine epidemic diarrhea virus (PEDV) envelope protein (E) is recognized as a viroporin that plays important functions in virus budding, assembly and virulence. Our previous study found that PEDV E protein induces endoplasmic reticulum stress (ERS), as well as suppresses the type I interferon (IFN) response, but their link and underlying mechanism remain obscure. To better understand this relationship, we investigated the roles of PEDV E protein-induced ERS in regulating cellular type I IFN production. Our results showed that PEDV E protein localized in the ER and triggered ERS through activation of PERK/eIF2α branch, as revealed by the up-regulated phosphorylation of PERK and eIF2α. PEDV E protein also significantly inhibited both poly(I:C)-induced and RIG-I signaling-mediated type I interferon production. The PERK/eIF2α branch of ERS activated by PEDV E protein led to the translation attenuation of RIG-I signaling-associated antiviral proteins, resulting in the suppression of type I IFN production. However, PEDV E protein had no effect on the mRNA transcription of RIG-I-associated molecules. Moreover, suppression of ERS with 4-PBA, a widely used ERS inhibitor, restored the expression of RIG-I-signaling-associated antiviral proteins and mRNA transcription of IFN-ß and ISGs genes to their normal levels, suggesting that PEDV E protein blocks the production of type I IFN through inhibiting expression of antiviral proteins caused by ERS-mediated translation attenuation. This study elucidates the mechanism by which PEDV E protein specifically modulates the ERS to inhibit type I IFN production, which will augment our understanding of PEDV E protein-mediated virus evasion of host innate immunity.


Subject(s)
Coronavirus Infections , Interferon Type I , Porcine epidemic diarrhea virus , Swine Diseases , Swine , Animals , Antiviral Agents , Endoplasmic Reticulum Stress , Cell Line , Eukaryotic Initiation Factor-2 , RNA, Messenger , Coronavirus Infections/veterinary
4.
Chest ; 162(4):A1192, 2022.
Article in English | EMBASE | ID: covidwho-2060788

ABSTRACT

SESSION TITLE: Rare Genetic Mutations and Anatomical Variants SESSION TYPE: Rapid Fire Case Reports PRESENTED ON: 10/18/2022 12:25 pm - 01:25 pm INTRODUCTION: Idiopathic pulmonary fibrosis (IPF) is a fatal disease affecting older adults that results in progressive scarring of the lung parenchyma. Familial IPF (FPF), defined by disease in two or more first-degree relatives, is estimated to occur in 2–20% of all IPF cases and can present with varying phenotypes which may be difficult to diagnose. Inherited gene variation as well as environmental factors predispose a patient to disease development. Additionally, rare genetic variants in the genes encoding surfactant A (SFTPA1, and SFTPA2) that affect alveolar stability and endoplasmic reticulum stress have been reported in less than 1% of FPF cases. Understanding these genetic variants is essential in the diagnosis and management of patients with FPF. CASE PRESENTATION: A 47-year-old Hispanic male with a history of COVID-19 one year ago (not requiring hospitalization) presented to the hospital for a two-day history of subjective fever and shortness of breath. He was hypoxic requiring oxygen via high flow nasal cannula. He was admitted four months ago for shortness of breath and treated for pneumonia. Since then, he has had chronic dyspnea with exertion. Computed tomography of the chest showed extensive ground glass opacities, worse in the right lung, with basilar and upper lobe honeycombing, and air bronchograms in the bilateral lower lobes. Family history was significant for a mother, maternal aunt, maternal grandfather, and maternal cousin who all died from pulmonary fibrosis. His maternal cousin was treated at our facility, in which genetic sequencing revealed a mutation in SFTPA2, c.697T>C. Our patient was found to have the same genetic mutation. DISCUSSION: The genetic basis of IPF remains poorly understood. Prior studies suggest only 20-30% of FPF cases harbor an identifiable causative genetic variant. Rare variants in two biologic pathways contribute to the known heritability of FPF including pathologic variants in surfactant related genes which cause improper protein trafficking leading to endoplasmic reticulum stress, defects in autophagy, and type II alveolar cell toxicity. SFTPA1 and SFTPA2 variants have been associated with FPF and lung adenocarcinoma in a small number of families and there are few reported cases. While currently the SFTPA2, c.697T>C mutation, previously reported by our group in 2016, is considered a variant of unknown significance, its occurrence in two relatives with serious progressive interstitial lung diseases suggests that it is indeed pathogenic. CONCLUSIONS: Gene sequencing should be considered for all patients with a family history of pulmonary fibrosis as identification of a rare genetic variant may offer guidance to diagnosis, prognostication, and risk stratification when considering lung transplantation as well as identify additional relatives who may be affected by IPF. Reference #1: Kropski JA, Young LR, Cogan JD, et al. Genetic Evaluation and Testing of Patients and Families with Idiopathic Pulmonary Fibrosis. Am J Respir Crit Care Med. 2017;195(11):1423-1428. doi:10.1164/rccm.201609-1820PP Reference #2: Wang Y, Kuan PJ, Xing C, Cronkhite JT, Torres F, Rosenblatt RL, DiMaio JM, Kinch LN, Grishin NV, Garcia CK. Genetic defects in surfactant protein A2 are associated with pulmonary fibrosis and lung cancer. Am J Hum Genet. 2009 Jan;84(1):52-9. doi: 10.1016/j.ajhg.2008.11.010. Epub 2008 Dec 18. PMID: 19100526;PMCID: PMC2668050. Reference #3: Pulmonary Fibrosis Due to a Novel Surfactant Protein Mutation R.A. Arciniegas Flores, I.A. Vital, K. Medepalli, D. DeMarzo, M.K. Glassberg Csete, R.A. Alvarez. https://doi.org/10.1164/ajrccm-conference.2019.199.1_Meetings.A5437 DISCLOSURES: No relevant relationships by Roger Alvarez No relevant relationships by Eduardo Lopez Gonzalez No relevant relationships by Anita Singh

5.
Biochemistry (Mosc) ; 87(9): 916-931, 2022 Sep.
Article in English | MEDLINE | ID: covidwho-2038256

ABSTRACT

Endoplasmic reticulum (ER) is a multifunctional membrane-enclosed organelle. One of the major ER functions is cotranslational transport and processing of secretory, lysosomal, and transmembrane proteins. Impaired protein processing caused by disturbances in the ER homeostasis results in the ER stress. Restoration of normal ER functioning requires activation of an adaptive mechanism involving cell response to misfolded proteins, the so-called unfolded protein response (UPR). Besides controlling protein folding, UPR plays a key role in other physiological processes, in particular, differentiation of cells of connective, muscle, epithelial, and neural tissues. Cell differentiation is induced by the physiological levels of ER stress, while excessive ER stress suppresses differentiation and can result in cell death. So far, it remains unknown whether UPR activation induces cell differentiation or if UPR is initiated by the upregulated synthesis of secretory proteins during cell differentiation. Cell differentiation is an important stage in the development of multicellular organisms and is tightly controlled. Suppression or excessive activation of this process can lead to the development of various pathologies in an organism. In particular, impairments in the differentiation of connective tissue cells can result in the development of fibrosis, obesity, and osteoporosis. Recently, special attention has been paid to fibrosis as one of the major complications of COVID-19. Therefore, studying the role of UPR in the activation of cell differentiation is of both theoretical and practical interest, as it might result in the identification of molecular targets for selective regulation of cell differentiation stages and as well as the potential to modulate the mechanisms involved in the development of various pathological states.


Subject(s)
COVID-19 , Endoplasmic Reticulum Stress , Cell Differentiation , Fibrosis , Humans , Unfolded Protein Response
6.
Iranian Journal of Pharmaceutical Research ; 21(1), 2022.
Article in English | EMBASE | ID: covidwho-2033387

ABSTRACT

Donepezil hydrochloride is an acetylcholine esterase inhibitor studied and approved to treat Alzheimer’s disease (AD). However, this drug can have positive therapeutic potential in treating different conditions, including various neurodegenerative disorders such as other types of dementia, multiple sclerosis, Parkinson’s disease, psychiatric and mood disorders, and even infectious diseases. Hence, this study reviewed the therapeutic potential of this drug in treating Alzheimer’s and other diseases by reviewing the articles from databases including Web of Science, Scopus, PubMed, Cochrane, and Science Direct. It was shown that donepezil could affect the pathophysiology of these diseases via mechanisms such as increasing the concentration of acetylcholine, modulating local and systemic inflammatory processes, affecting acetylcholine receptors like nicotinic and muscarinic receptors, and activating various cellular signaling via receptors like sigma-1 receptors. Despite many therapeutic potentials, this drug has not yet been approved for treating non-Alzheimer’s diseases, and more comprehensive studies are needed.

7.
Gastroenterology ; 162(7):S-364, 2022.
Article in English | EMBASE | ID: covidwho-1967299

ABSTRACT

Background: Diarrhea is present in up to 36.6% of patients with COVID-19. The mechanism of SARS-CoV-2-induced diarrhea remains unclear. We hypothesized that enterocyte-enteric neuron interactions were important in SARS-CoV-2-induced diarrhea. SARS-CoV-2 induces endoplasmic reticulum (ER) stress in enterocytes causing the release of Damage Associated Molecular Patterns (DAMPs). The DAMPs then stimulate the release of enteric neurotransmitters that disrupt gut electrolyte homeostasis. The influence of ER stress and enteric neuronderived vasoactive intestinal peptide (VIP) on the expression of Na+/H+ exchanger 3 (NHE3), an important transporter that mediates intestinal Na+/fluid absorption, was further examined. Methods: SARS-CoV-2 propagated in Vero-E6 cells was used to infect Caco-2, a human colon epithelial cell line that expresses SARS-CoV-2 entry receptor ACE2. The expression of ER stress markers, phospho-PERK, Xbp1s, and DAMP proteins, was examined by Western blotting. Primary mouse enteric neurons were treated with a conditioned medium of Caco- 2 cells that were infected with SARS-CoV-2 or treated with tunicamycin. VIP expression by cultured enteric neurons was assessed by RT-qPCR, Western blotting, and ELISA. Membrane expression of NHE3 was determined by surface biotinylation. Results: SARS-CoV-2 infection of Caco-2 cells led to increased expression of phospho-PERK and Xbp1s indicating increased ER stress. Infected Caco-2 cells secreted DAMP proteins, including HSP70 and calreticulin, as revealed by proteomic and Western analyses. The expression of VIP mRNA in enteric neurons was up-regulated after treatment with a conditioned medium of SARS-CoV-2- infected Caco-2 cells (Mock, 1 ± 0.0885;and SARS-CoV-2, 1.351 ± 0.020, P=.005). CD91, a receptor for HSP70 and calreticulin, is abundantly expressed in cultured mouse and human enteric neurons and was up-regulated by a conditioned medium of SARS-CoV-2-infected Caco-2 cells. Tunicamycin, an inducer of ER stress, also induced the secretion of HSP70 and calreticulin, mimicking SARS-CoV-2 infection. Moreover, co-culture of enteric neurons with tunicamycin-treated Caco-2 cells stimulated VIP production as determined by ELISA. Co-treatment of Caco-2 cells with tunicamycin (apical) and VIP (basolateral) induced a synergistic decrease in the membrane expression of NHE3. Conclusions: Our findings demonstrate that SARS-CoV-2 infection of enterocytes leads to ER stress and the release of DAMPs that up-regulate the expression and release of VIP by enteric neurons. The presence of ER stress together with the secreted VIP, in turn, inhibits fluid absorption through the downregulation of brush-border membrane expression of NHE3 in the enterocytes. These data highlight epithelial-neuronal crosstalk in COVID-19 related diarrhea. (Figure Presented)

8.
INDIAN JOURNAL OF PHARMACEUTICAL SCIENCES ; 84:190-201, 2022.
Article in English | Web of Science | ID: covidwho-1939749

ABSTRACT

Phellodendrine is a Phellodendri Cortex-derived isoquinoline alkaloids, has been shown to have various activities, especially hypoglycemic effect in mice, predicting its medicinal value on diabetes mellitus. To further understand the pharmacological effect of phellodendrine on diabetes mellitus, network pharmacological techniques have been used to elaborate the involved mechanisms. 84 common target molecules were screened, based on the chemical structure of phellodendrine molecule and disease database. These proteins were enriched in insulin resistance, insulin secretion and inflammatory response, mainly focus on the phosphatidylinositol 3-kinase/protein kinase B signaling pathway, mitogen-activated protein kinase signaling pathway and interleukin-17 signaling pathway. Moreover, enrichment analysis suggested that the targets of phellodendrine such as phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha and mitogen-activated protein kinases 8 were associated with coronavirus disease 2019. To verify the results, molecular docking technique was used to evaluate the interaction between phellodendrine and key targets in the signaling pathway. The calculated binding energy indicates that phellodendrine can form stable complex with insulin receptor, mitogen-activated protein kinases 8, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha and glycogen synthase kinase 3 beta. These data suggest that phellodendrine should be beneficial for treatment of diabetes mellitus.

9.
Alcoholism: Clinical and Experimental Research ; 46:142A, 2022.
Article in English | EMBASE | ID: covidwho-1937893

ABSTRACT

As the delta and omicron SARS-CoV-2 variants spread across the world, more tools to fight off serious infection have been developed. COVID antiviral drugs that can be taken orally at home could cut serious illness and reduce the risk of hospitalization and death. However, significant population of people consume alcohol before the infection and use of the antiviral drugs, which could potentiate side effects of the drugs on the liver. We investigated the role of alcohol in anti-Covid drug-induced stress responses in live cells. METHODS: HepG2 cells or primary mouse hepatocytes (PMH) were pre-treated with alcohol (50 mMlow dose or 100 mMhigh dose) for 6-24 hours and then treated with the newly developed oral anti-Covid drugs: nirmatrelvir, ritonavir, molnupiravir, and remdesivir at 10- 30 lg/ml for 6-24 hours. Unfolded protein response (UPR)/ER stress molecular markers (e.g. IRE1 GRP78, PERK, Xbp1 and CHOP), Golgi stress response (GSR) markers of GCP60, HSP47 and TFE3, and STAT3 were measured after the treatments. Cell death was assessed through double staining the liver cells with Syntox Green and Hoesche's Blue. RESULTS: ER stress response as indicated by IRE1, Xbp1 and CHOP was insignificant or mild in either HepG2 or PMH treated individually with alcohol at the low dose, nirmatrelvir, ritonavir, molnupiravir, or remdesivir. Alcohol or remdesivir induced moderate GSR based on mRNA increase of GCP60, HSP47 and TFE3, which was accompanied with apparent Golgi fragmentation in either HepG2 or PMH. Cell death rates in HepG2 treated with alcohol, nirmatrelvir, ritonavir, molnupiravir, or remdesivir individually were less than 5%. Pre-exposure to alcohol combined with subsequent treatment with nirmatrelvir, ritonavir molnupiravir, or remdesivir significantly increased both ER stress and GSR markers and expression of phosphorylated STAT3 (p-STAT3). Most significantly, cell death rates in HepG2 or PMH were increased by 2- to 5-fold by pre-alcohol exposure plus ritonavir, nirmatrelvir, molnupiravir, or remdesivir. The organelle stress markers, p-STAT3 and cell death were all further increased in alcoholand anti-Covid drug-treated HepG2 or primary mouse hepatocytes that were pre-infected with the lentiviruses that were pseudotyped with the SARS-CoV-2 spike protein. CONCLUSION: Our results indicate that pre-exposure to alcohol potentiates the liver cells to anti-Covid-19 drugs induced stress responses and cell death.

10.
American Journal of Respiratory and Critical Care Medicine ; 205(1), 2022.
Article in English | EMBASE | ID: covidwho-1927865

ABSTRACT

RATIONALE: Airway inflammation plays a role in airway diseases such as asthma, chronic obstructive pulmonary disease (COPD), chronic bronchitis, and COVID-19 that affect millions of people worldwide. Previously, we showed that acute (24-h) exposure to the pro-inflammatory cytokine tumor necrosis factor α (TNFα) triggers an endoplasmic reticulum (ER) stress response in human airway smooth muscle (hASM) cells. In hASM cells, TNFα selectively activates the inositol requiring enzyme 1α (IRE1α) ER stress pathway with downstream splicing of X-box binding protein 1 (XBP1s), which transcriptionally activates expression of target genes that include proteins mediating phosphorylation of dynamin-related protein 1 (pDRP1) at the Ser616 (S616) residue. Increased pDRP1 at S616 is associated with mitochondrial fission (fragmentation);however, DRP1 is also phosphorylated at Ser637 (S637) residue, and the balance between phosphorylation at S616 and S637 regulates the translocation of DRP1 from cytosol to mitochondria and subsequent fragmentation of mitochondria. In the present study, we hypothesized that TNFα induces ER stress leading to XBP1s mediated increase in the expression of specific kinases that phosphorylate DRP1 at S616 and promote mitochondrial fragmentation. METHODS: hASM cells, dissociated from bronchial tissue obtained from patients with no history of respiratory diseases, were exposed to TNFα (20 ng/ ml for 6-h). As an inhibitor of fragmentation, cells were treated with Mdivi1 (50 μM for 6-h), GTPase inhibitor of DRP1. The expression and phosphorylation status of IRE1α, DRP1, XBP1, cyclin dependent kinases (CDK1, CDK5) and cyclin B1 were quantified by Western blot and immunohistochemistry. Mitochondrial morphology was assessed by 3D confocal microscopy using MitoTracker. XBP1-targets were confirmed by chromatin immunoprecipitation (ChIP) and quantitative PCR. RESULTS: Bioinformatics analysis predicted putative binding sites of XBP1 in the promoter region of CDK1, CDK5 and cyclin B1 genes that are reported to phosphorylate DRP1 at S616. Consistent with our previous findings, we found that TNFα increases IRE1α phosphorylation and XBP1 splicing. The TNFα induced increase in XBP1s transcriptionally activated expression of CDK1, CDK5 and cyclin B1 and leads to subsequent phosphorylation of DRP1 at S616 with no change in S637 phosphorylation. As a result, TNFα mediated increase in the ratio of S616/ S637 phosphorylation, which promoted translocation of DRP1 from cytosol to mitochondria and mitochondrial fragmentation. We also showed that Mdivi1 mediated inhibition of DRP1-GTPase activity ameliorated phosphorylation at S616 residue and significantly reduced mitochondrial fragmentation. CONCLUSIONS: The present study elucidates the mechanism underlying TNFα induced ER stress and mitochondrial fragmentation.

11.
J Virol ; 96(1): e0169521, 2022 01 12.
Article in English | MEDLINE | ID: covidwho-1816694

ABSTRACT

The replication of coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is closely associated with the endoplasmic reticulum (ER) of infected cells. The unfolded protein response (UPR), which is mediated by ER stress (ERS), is a typical outcome in coronavirus-infected cells and is closely associated with the characteristics of coronaviruses. However, the interaction between virus-induced ERS and coronavirus replication is poorly understood. Here, we demonstrate that infection with the betacoronavirus porcine hemagglutinating encephalomyelitis virus (PHEV) induced ERS and triggered all three branches of the UPR signaling pathway both in vitro and in vivo. In addition, ERS suppressed PHEV replication in mouse neuro-2a (N2a) cells primarily by activating the protein kinase R-like ER kinase (PERK)-eukaryotic initiation factor 2α (eIF2α) axis of the UPR. Moreover, another eIF2α phosphorylation kinase, interferon (IFN)-induced double-stranded RNA-dependent protein kinase (PKR), was also activated and acted cooperatively with PERK to decrease PHEV replication. Furthermore, we demonstrate that the PERK/PKR-eIF2α pathways negatively regulated PHEV replication by attenuating global protein translation. Phosphorylated eIF2α also promoted the formation of stress granules (SGs), which in turn repressed PHEV replication. In summary, our study presents a vital aspect of the host innate response to invading pathogens and reveals attractive host targets (e.g., PERK, PKR, and eIF2α) for antiviral drugs. IMPORTANCE Coronavirus diseases are caused by different coronaviruses of importance in humans and animals, and specific treatments are extremely limited. ERS, which can activate the UPR to modulate viral replication and the host innate response, is a frequent occurrence in coronavirus-infected cells. PHEV, a neurotropic betacoronavirus, causes nerve cell damage, which accounts for the high mortality rates in suckling piglets. However, it remains incompletely understood whether the highly developed ER in nerve cells plays an antiviral role in ERS and how ERS regulates viral proliferation. In this study, we found that PHEV infection induced ERS and activated the UPR both in vitro and in vivo and that the activated PERK/PKR-eIF2α axis inhibited PHEV replication through attenuating global protein translation and promoting SG formation. A better understanding of coronavirus-induced ERS and UPR activation may reveal the pathogenic mechanism of coronavirus and facilitate the development of new treatment strategies for these diseases.


Subject(s)
Betacoronavirus 1/physiology , Coronavirus Infections/metabolism , Eukaryotic Initiation Factor-2/metabolism , Virus Replication/physiology , eIF-2 Kinase/metabolism , Animals , Betacoronavirus 1/metabolism , Cell Line , Coronavirus Infections/virology , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/ultrastructure , Endoplasmic Reticulum Stress , Mice , Phosphorylation , Protein Biosynthesis , Signal Transduction , Unfolded Protein Response
12.
Cancer Immunology Research ; 10(1 SUPPL), 2022.
Article in English | EMBASE | ID: covidwho-1675745

ABSTRACT

The proceedings contain 100 papers. The topics discussed include: unconventional er stress response pro-tumorigenic polarization and survival in TAMs;tumor microenvironment metabolism in T cell differentiation and dysfunction;CAR NK cells: the future of cancer immunotherapy;chimeric antigen receptor macrophages for the treatment of solid tumors;impact of immunotherapy on COVID-19 immunity: insights from checkpoint blockade in cancer;adaptive immune dysregulation in cancer patients with SARS-CoV-2 infection;mapping myeloid programs that control tumor immunity;and cancer evolution: chromosomal instability and immune evasion.

13.
Kidney Int ; 101(6): 1216-1231, 2022 06.
Article in English | MEDLINE | ID: covidwho-1665244

ABSTRACT

Risk variants of the apolipoprotein-L1 (APOL1) gene are associated with severe kidney disease, putting homozygous carriers at risk. Since APOL1 lacks orthologs in all major model organisms, a wide range of mechanisms frequently in conflict have been described for APOL1-associated nephropathies. The genetic toolkit in Drosophila allows unique in vivo insights into disrupted cellular homeostasis. To perform a mechanistic analysis, we expressed human APOL1 control and gain-of-function kidney risk variants in the podocyte-like garland cells of Drosophila nephrocytes and a wing precursor tissue. Expression of APOL1 risk variants was found to elevate endocytic function of garland cell nephrocytes that simultaneously showed early signs of cell death. Wild-type APOL1 had a significantly milder effect, while a control transgene with deletion of the short BH3 domain showed no overt phenotype. Nephrocyte endo-lysosomal function and slit diaphragm architecture remained unaffected by APOL1 risk variants, but endoplasmic reticulum (ER) swelling, chaperone induction, and expression of the reporter Xbp1-EGFP suggested an ER stress response. Pharmacological inhibition of ER stress diminished APOL1-mediated cell death and direct ER stress induction enhanced nephrocyte endocytic function similar to expression of APOL1 risk variants. We confirmed APOL1-dependent ER stress in the Drosophila wing precursor where silencing the IRE1-dependent branch of ER stress signaling by inhibition with Xbp1-RNAi abrogated cell death, representing the first rescue of APOL1-associated cytotoxicity in vivo. Thus, we uncovered ER stress as an essential consequence of APOL1 risk variant expression in vivo in Drosophila, suggesting a central role of this pathway in the pathogenesis of APOL1-associated nephropathies.


Subject(s)
Kidney Diseases , Podocytes , Animals , Apolipoprotein L1/genetics , Drosophila/genetics , Endoplasmic Reticulum Stress/genetics , Humans , Kidney Diseases/pathology , Podocytes/pathology
14.
Journal of Virology ; 96(1):1-23, 2022.
Article in English | A9H | ID: covidwho-1647636

ABSTRACT

The replication of coronaviruses, including severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERSCoV), and the recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is closely associated with the endoplasmic reticulum (ER) of infected cells. The unfolded protein response (UPR), which is mediated by ER stress (ERS), is a typical outcome in coronavirus-infected cells and is closely associated with the characteristics of coronaviruses. However, the interaction between virus-induced ERS and coronavirus replication is poorly understood. Here, we demonstrate that infection with the betacoronavirus porcine hemagglutinating encephalomyelitis virus (PHEV) induced ERS and triggered all three branches of the UPR signaling pathway both in vitro and in vivo. In addition, ERS suppressed PHEV replication in mouse neuro-2a (N2a) cells primarily by activating the protein kinase R-like ER kinase (PERK)-eukaryotic initiation factor 2α (eIF2α) axis of the UPR. Moreover, another eIF2a phosphorylation kinase, interferon (IFN)-induced double-stranded RNA-dependent protein kinase (PKR), was also activated and acted cooperatively with PERK to decrease PHEV replication. Furthermore, we demonstrate that the PERK/PKR-eIF2a pathways negatively regulated PHEV replication by attenuating global protein translation. Phosphorylated eIF2a also promoted the formation of stress granules (SGs), which in turn repressed PHEV replication. In summary, our study presents a vital aspect of the host innate response to invading pathogens and reveals attractive host targets (e.g., PERK, PKR, and eIF2a) for antiviral drugs. [ FROM AUTHOR] Copyright of Journal of Virology is the property of American Society for Microbiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

15.
Gastroenterology ; 160(6):S-233-S-234, 2021.
Article in English | EMBASE | ID: covidwho-1594011

ABSTRACT

Background: Up to 36.6% of COVID-19 patients have diarrheal symptoms and 48.1% test positive for SARS-CoV-2 via stool test. The mechanism of SARS-CoV-2-associated diarrhea remains poorly understood. We hypothesize that crosstalk between enterocytes and the enteric nervous system (ENS) plays a critical role in the pathogenesis of COVID-19-associated diarrhea. We studied the effects of SARS-CoV-2 on induction of endoplasmic reticulum (ER) stress and release of Damage Associated Molecular Patterns (DAMPs), which act on enteric neurons and stimulate the production of neurotransmitters. The influence of ER stress and enteric neuron-derived vasoactive intestinal peptide (VIP) on the expression of electrolyte transporter Na+/H+ exchanger 3 (NHE3) was also examined. Methods: SARS-CoV-2 (2019-nCoV/USA-WA1/2020) was propagated in Vero-E6 cells. Caco-2, a human colon epithelial cell line, expresses the essential SARS-CoV-2 entry receptor ACE2 and was thus used for infection (MOI, ~0.01). We used Western blotting to assess the expression of ER stress (phospho-PERK and Xbp1s) and DAMP (HMGB1) markers at 48 hours post-infection. Primary mouse enteric neurons were co-cultured with Caco-2 cells, pre-treated for 24 hours with 2 μM tunicamycin to induce ER stress. Supernatants from enteric neurons were used to assess the expression of VIP by ELISA. Primary enteric neurons were treated with HMGB1 or ATP (another form of DAMPs), and the expression of c-FOS, a marker of neuronal activity, was determined by Western blotting and immunofluorescence staining. Results: We found that SARS-CoV-2 infection of Caco-2 cells led to increased expression of phospho-PERK and Xbp1s. Compared to uninfected control, infected Caco-2 cells secreted HMGB1 into culture media, indicating epithelial production of DAMPs in response to SARS-CoV-2 infection. Tunicamycin was used to induce ER-stress and secretion of HMGB1 by Caco-2, mimicking SARS-CoV-2 infection. Importantly, enteric neurons co-cultured with tunicamycin-treated Caco-2 cells secreted significantly higher levels of VIP. Treating Caco-2 cells with tunicamycin or VIP on the basolateral side led to decreased surface NHE3 expression, suggesting a potential impairment of intestinal electrolyte/fluid absorption. More-over, HMGB1 and ATP both increased the expression of phospho-c-FOS in cultured enteric neurons, indicating DAMP-induced neuronal activation. Conclusions: Our findings demon-strate that enterocytes infected by SARS-CoV-2 release DAMPs with the capacity to induce VIP secretion by the enteric neurons, which in turn acts on enterocytes and inhibits apical localization of NHE3. These findings establish basic mechanisms relevant to diarrheal disease in COVID-19 patients and identify potential targets for the treatment of SARS-CoV-2 infection of the gastrointestinal tract.

16.
Gastroenterology Insights ; 12(2):259-269, 2021.
Article in English | EMBASE | ID: covidwho-1572427

ABSTRACT

Background: Gut microbiota is a complex ecosystem of bacteria, viruses, archaea, protozoa and yeasts in our intestine. It has several functions, including maintaining human body equilibrium. Microbial “dysbiosis” can be responsible for outbreak of local and systemic infections, especially in critically ill patients. Methods: to build a narrative review, we performed a Pubmed, Medline and EMBASE search for English language papers, reviews, meta-analyses, case series and randomized controlled trials (RCTs) by keywords and their associations: critically ill patient;nutrition;gut microbiota;probiotics;gut virome;SARS-COV 2. Results: Over the antibiotic-based “selective decontamination”, potentially responsible for drug-resistant microorganisms development, there is growing interest of scientists and the pharmaceutical industry for pre-, probiotics and their associations as safe and reliable remedies restoring gut microbial “eubiosis”. Very first encouraging evidences link different gut microbiota profiles with SARS-COV 2 disease stage and gravity. Thus, there is frame for a probiotic therapeutic approach of COVID-19. Conclusions: gut microbiota remodulation seems to be a promising and safe therapeutic approach to prevent local and systemic multi-resistant bug infections in the intensive care unit (ICU) patients. This approach deserves more and more attention at the time of SARS-COV 2 pandemic.

17.
European Heart Journal ; 42(SUPPL 1):3349, 2021.
Article in English | EMBASE | ID: covidwho-1554712

ABSTRACT

Objective: SARS-CoV-2 causes the coronavirus disease 2019 (COVID-19) and has spawned a global health crisis. Virus infection can lead to elevated markers of cardiac injury and inflammation associated with a higher risk of mortality. However, it is so far unclear whether cardiovascular damage is caused by direct virus infection or is mainly secondary due to inflammation. Recently, additional novel SARS-CoV-2 variants have emerged accounting for more than 70% of all cases in Germany. To what extend these variants differ from the original strain in their pathology remains to be elucidated. Here, we investigated the effect of the novel SARS-CoV-2 variants on cardiovascular cells. Results: To study whether cardiovascular cells are permissive for SARSCoV-2, we inoculated human iPS-derived cardiomyocytes and endothelial cells from five different origins, including umbilical vein endothelial cells, coronary artery endothelial cells (HCAEC), cardiac and lung microvascular endothelial cells, or pulmonary arterial cells, in vitro with SARS-CoV-2 isolates (G614 (original strain), B.1.1.7 (British variant), B.1.351 (South African variant) and P.1 (Brazilian variant)). While the original virus strain infected iPS-cardiomyocytes and induced cell toxicity 96h post infection (290±10 cells vs. 130±10 cells;p=0.00045), preliminary data suggest a more severe infection by the novel variants. To what extend the response to the novel variants differ from the original strain is currently investigated by phosphoproteom analysis. Of the five endothelial cells studied, only human coronary artery EC took up the original virus strain, without showing viral replication and cell toxicity. Spike protein was only detected in the perinuclear region and was co-localized with calnexin-positive endosomes, which was accompanied by elevated ER-stress marker genes, such as EDEM1 (1.5±0.2-fold change;p=0.04). Infection with the novel SARS-CoV-2 variants resulted in significant higher levels of viral spike compared to the current strain. Surprisingly, viral up-take was also seen in other endothelial cell types (e.g. HUVEC). Although no viral replication was observed (850±158 viral RNA copies at day 0 vs. 197±43 viral RNA copies at day 3;p=0.01), the British SARS-CoV-2 variant B.1.1.7 reduced endothelial cell numbers (0.63±0.03-fold change;p=0.0001). Conclusion: Endothelial cells and cardiomyocytes showed a distinct response to SARS-CoV-2. Whereas cardiomyocytes were permissively infected, endothelial cells took up the virus, but were resistant to viral replication. However, both cell types showed signs of increased toxicity induced by the British SARS-CoV-2 variant. These data suggest that cardiac complications observed in COVID-19 patients might at least in part be based on direct infection of cardiovascular cells. The more severe cytotoxic effects of the novel variants implicate that patients infected with the new variants should be even more closely monitored.

18.
Inflammopharmacology ; 30(1): 343-348, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1530348

ABSTRACT

We have previously published several papers illustrating numerous immunomodulatory and anti-inflammatory potential benefits when we repurposed safe, generic non-steroidal anti-inflammatory drugs (NSAIDs)/nitazoxanide/azithromycin (Kelleni's protocol), to early manage our COVID-19 pediatric, adult, and pregnant patients. In this manuscript, we discuss some recently published meta-analysis and clinical studies supporting our practice and discuss a molecular study that might be interpreted as an academic proof that our protocol might also prevent SARS-CoV-2 replication. Moreover, after aspirin has been suggested to be independently associated with reduced risk of mechanical ventilation, ICU admission and in-hospital mortality of COVID-19, we claim that the molecular interpretation of the results that led to this suggestion was not scientifically accurate, and we provide our academic interpretation confirming that low-dose aspirin is least likely to improve COVID-19 mortality through anticoagulation as was suggested. Furthermore, we describe other potential benefits related to aspirin-triggered lipoxins and resolvins while illustrating how NSAIDs interfere with COX-1, COX-2, SARS-CoV-2/ SARS-CoV-2 ORF protein-dependent activation of caspases and their subsequent mitochondrial dysfunction, endoplasmic reticulum stress, apoptosis and necroptosis which were associated with COVID-19 complications. Similarly, NSAIDs are known caspase inhibitors and thus they might independently inhibit other caspase-related COVID-19-associated downstream pathological signaling mechanisms. Finally, we postulated that CARD-14, a caspase recruitment domain-containing protein, polymorphisms might play a role in the development of severe and critical COVID-19 and confirmed our old call to early adopt NSAIDs, as an integral part of Kelleni's protocol, as of choice in its management aiming to end this pandemic.


Subject(s)
COVID-19 , Adult , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , COVID-19/drug therapy , Child , Humans , Pandemics , SARS-CoV-2
19.
Biomed Pharmacother ; 143: 112110, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1377338

ABSTRACT

The catalysis of disulphide (SS) bonds is the most important characteristic of protein disulphide isomerase (PDI) family. Catalysis occurs in the endoplasmic reticulum, which contains many proteins, most of which are secretory in nature and that have at least one s-s bond. Protein disulphide isomerase A3 (PDIA3) is a member of the PDI family that acts as a chaperone. PDIA3 is highly expressed in response to cellular stress, and also intercept the apoptotic cellular death related to endoplasmic reticulum (ER) stress, and protein misfolding. PDIA3 expression is elevated in almost 70% of cancers and its expression has been linked with overall low cell invasiveness, survival and metastasis. Viral diseases present a significant public health threat. The presence of PDIA3 on the cell surface helps different viruses to enter the cells and also helps in replication. Therefore, inhibitors of PDIA3 have great potential to interfere with viral infections. In this review, we summarize what is known about the basic structure, functions and role of PDIA3 in viral infections. The review will inspire studies of pathogenic mechanisms and drug targeting to counter viral diseases.


Subject(s)
Protein Disulfide-Isomerases/metabolism , Virus Diseases/enzymology , Virus Diseases/virology , Virus Internalization , Virus Replication , Viruses/growth & development , Animals , Antiviral Agents/therapeutic use , Enzyme Inhibitors/therapeutic use , Host-Pathogen Interactions , Humans , Protein Disulfide-Isomerases/antagonists & inhibitors , Virus Diseases/drug therapy , Viruses/pathogenicity
20.
Cell J ; 23(2): 247-250, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1259824

ABSTRACT

Angiotensin-converting enzyme II (ACE2) in association with type II transmembrane serine protease (TMPRSS2) is considered the main receptor of SARS-CoV-2. However, considering the clinical complications of COVID-19 in different organs, there is no strong association between the abundance of ACE2/TMPRSS2 co-expression and clinical features of the disease and the severity of complications. Since SARS-CoV-2 affects certain organs that lack or have low expression of ACE2/TMPRSS2, it may be possible that the virus employs other receptors for colonization and entry. Based on recent studies, glucose-regulated protein 78 (GRP78) can be a potential alternative receptor for SARS-CoV-2 entry. In this letter, supporting evidence proposed GRP78 as an alternative receptor in SARS-CoV-2 infection.

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