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1.
J Inorg Biochem ; 231: 111777, 2022 06.
Article in English | MEDLINE | ID: covidwho-1873158

ABSTRACT

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic is currently the major challenge to global public health. Two proteases, papain-like protease (PLpro) and the 3-chymotrypsin-like protease (3CLpro or Mpro), are indispensable for SARS-CoV-2 replication, making them attractive targets for antiviral therapy development. Here we screened a panel of essential metal ions using a proteolytic assay and identified that zinc gluconate, a widely-used zinc supplement, strongly inhibited the proteolytic activities of the two proteases in vitro. Biochemical and crystallographic data reveal that zinc gluconate exhibited the inhibitory function via binding to the protease catalytic site residues. We further show that treatment of zinc gluconate in combination with a small molecule ionophore hinokitiol, could lead to elevated intracellular Zn2+ level and thereby significantly impaired the two protease activities in cellulo. Particularly, this approach could also be applied to rescue SARS-CoV-2 infected mammalian cells, indicative of potential application to combat coronavirus infections. Our studies provide the direct experimental evidence that elevated intracellular zinc concentration directly inhibits SARS-CoV-2 replication and suggest the potential benefits to use the zinc supplements for coronavirus disease 2019 (COVID-19) treatment.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Antiviral Agents/chemistry , Antiviral Agents/pharmacology , COVID-19/drug therapy , Gluconates , Mammals/metabolism , Monoterpenes , Peptide Hydrolases/metabolism , Tropolone/analogs & derivatives , Zinc/pharmacology
2.
N Engl J Med ; 386(9): 815-826, 2022 03 03.
Article in English | MEDLINE | ID: covidwho-1721751

ABSTRACT

BACKGROUND: Whether the use of balanced multielectrolyte solution (BMES) in preference to 0.9% sodium chloride solution (saline) in critically ill patients reduces the risk of acute kidney injury or death is uncertain. METHODS: In a double-blind, randomized, controlled trial, we assigned critically ill patients to receive BMES (Plasma-Lyte 148) or saline as fluid therapy in the intensive care unit (ICU) for 90 days. The primary outcome was death from any cause within 90 days after randomization. Secondary outcomes were receipt of new renal-replacement therapy and the maximum increase in the creatinine level during ICU stay. RESULTS: A total of 5037 patients were recruited from 53 ICUs in Australia and New Zealand - 2515 patients were assigned to the BMES group and 2522 to the saline group. Death within 90 days after randomization occurred in 530 of 2433 patients (21.8%) in the BMES group and in 530 of 2413 patients (22.0%) in the saline group, for a difference of -0.15 percentage points (95% confidence interval [CI], -3.60 to 3.30; P = 0.90). New renal-replacement therapy was initiated in 306 of 2403 patients (12.7%) in the BMES group and in 310 of 2394 patients (12.9%) in the saline group, for a difference of -0.20 percentage points (95% CI, -2.96 to 2.56). The mean (±SD) maximum increase in serum creatinine level was 0.41±1.06 mg per deciliter (36.6±94.0 µmol per liter) in the BMES group and 0.41±1.02 mg per deciliter (36.1±90.0 µmol per liter) in the saline group, for a difference of 0.01 mg per deciliter (95% CI, -0.05 to 0.06) (0.5 µmol per liter [95% CI, -4.7 to 5.7]). The number of adverse and serious adverse events did not differ meaningfully between the groups. CONCLUSIONS: We found no evidence that the risk of death or acute kidney injury among critically ill adults in the ICU was lower with the use of BMES than with saline. (Funded by the National Health and Medical Research Council of Australia and the Health Research Council of New Zealand; PLUS ClinicalTrials.gov number, NCT02721654.).


Subject(s)
Acute Kidney Injury/prevention & control , Critical Illness/therapy , Saline Solution/therapeutic use , Acute Kidney Injury/etiology , Adult , Aged , Critical Care/methods , Critical Illness/mortality , Double-Blind Method , Female , Fluid Therapy , Gluconates/adverse effects , Gluconates/therapeutic use , Humans , Intensive Care Units , Magnesium Chloride/adverse effects , Magnesium Chloride/therapeutic use , Male , Middle Aged , Potassium Chloride/adverse effects , Potassium Chloride/therapeutic use , Saline Solution/adverse effects , Sodium Acetate/adverse effects , Sodium Acetate/therapeutic use , Sodium Chloride/adverse effects , Sodium Chloride/therapeutic use , Treatment Outcome
3.
Chembiochem ; 22(22): 3199-3207, 2021 11 16.
Article in English | MEDLINE | ID: covidwho-1406083

ABSTRACT

Site-specific protein modifications are vital for biopharmaceutical drug development. Gluconoylation is a non-enzymatic, post-translational modification of N-terminal HisTags. We report high-yield, site-selective in vitro α-aminoacylation of peptides, glycoproteins, antibodies, and virus-like particles (VLPs) with azidogluconolactone at pH 7.5 in 1 h. Conjugates slowly hydrolyse, but diol-masking with borate esters inhibits reversibility. In an example, we multimerise azidogluconoylated SARS-CoV-2 receptor-binding domain (RBD) onto VLPs via click-chemistry, to give a COVID-19 vaccine. Compared to yeast antigen, HEK-derived RBD was immunologically superior, likely due to observed differences in glycosylation. We show the benefits of ordered over randomly oriented multimeric antigen display, by demonstrating single-shot seroconversion and best virus-neutralizing antibodies. Azidogluconoylation is simple, fast and robust chemistry, and should accelerate research and development.


Subject(s)
Azides/chemistry , COVID-19 Vaccines/chemistry , Gluconates/chemistry , Glycine/chemistry , Histidine/chemistry , Lactones/chemistry , Vaccines, Virus-Like Particle/chemistry , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/immunology , Azides/immunology , COVID-19 Vaccines/immunology , Gluconates/immunology , Glycine/immunology , Histidine/immunology , Humans , Lactones/immunology , Models, Molecular , Molecular Structure , Vaccines, Virus-Like Particle/immunology
4.
J Trace Elem Med Biol ; 68: 126818, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1300926

ABSTRACT

CONTEXT: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) that emerged late in 2019 is the etiologic agent of coronavirus disease 2019 (Covid-19). There is an urgent need to develop curative and preventive therapeutics to limit the current pandemic and to prevent the re-emergence of Covid-19. This study aimed to assess the in vitro activity of copper gluconate against SARS-CoV-2. METHODS: Vero E6 cells were cultured with or without copper gluconate 18-24 hours before infection. Cells were infected with a recombinant GFP expressing SARS-CoV-2. Cells were infected with a recombinant GFP expressing SARS-CoV-2. Infected cells were incubated in fresh medium containing varying concentration of copper gluconate (supplemented with bovine serum albumin or not) for an additional 48 -h period. The infection level was measured by the confocal microscopy-based high content screening method. The cell viability in presence of copper gluconate was assessed by XTT and propidium iodide assays. RESULTS: The viability of Vero E6 cells exposed to copper gluconate up to 200 µM was found to be similar to that of unexposed cells, but it dropped below 70 % with 400 µM of this agent after 72 h of continuous exposure. The infection rate was 23.8 %, 18.9 %, 20.6 %, 6.9 %, 5.3 % and 5.2 % in cells treated prior infection with 0, 2, 10, 25, 50 and 100 µM of copper gluconate respectively. As compared to untreated cells, the number of infected cells was reduced by 71 %, 77 %, and 78 % with 25, 50, and 100 µM of copper gluconate respectively (p < 0.05). In cells treated only post-infection, the rate of infection dropped by 73 % with 100 µM of copper gluconate (p < 0.05). However, the antiviral activity of copper gluconate was abolished by the addition of bovine serum albumin. CONCLUSION: Copper gluconate was found to mitigate SARS-CoV-2 infection in Vero E6 cells but this effect was abolished by albumin, which suggests that copper will not retain its activity in serum. Furthers studies are needed to investigate whether copper gluconate could be of benefit in mucosal administration such as mouthwash, nasal spray or aerosols.


Subject(s)
Gluconates/pharmacology , Microscopy, Confocal , SARS-CoV-2/drug effects , Animals , Antiviral Agents/pharmacology , COVID-19/pathology , COVID-19/virology , Cell Survival/drug effects , Chlorocebus aethiops , Green Fluorescent Proteins/metabolism , Vero Cells
5.
JAMA Netw Open ; 4(2): e210369, 2021 02 01.
Article in English | MEDLINE | ID: covidwho-1084243

ABSTRACT

Importance: There is limited evidence regarding early treatment of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection to mitigate symptom progression. Objective: To examine whether high-dose zinc and/or high-dose ascorbic acid reduce the severity or duration of symptoms compared with usual care among ambulatory patients with SARS-CoV-2 infection. Design, Setting, and Participants: This multicenter, single health system randomized clinical factorial open-label trial enrolled 214 adult patients with a diagnosis of SARS-CoV-2 infection confirmed with a polymerase chain reaction assay who received outpatient care in sites in Ohio and Florida. The trial was conducted from April 27, 2020, to October 14, 2020. Intervention: Patients were randomized in a 1:1:1:1 allocation ratio to receive either 10 days of zinc gluconate (50 mg), ascorbic acid (8000 mg), both agents, or standard of care. Outcomes: The primary end point was the number of days required to reach a 50% reduction in symptoms, including severity of fever, cough, shortness of breath, and fatigue (rated on a 4-point scale for each symptom). Secondary end points included days required to reach a total symptom severity score of 0, cumulative severity score at day 5, hospitalizations, deaths, adjunctive prescribed medications, and adverse effects of the study supplements. Results: A total of 214 patients were randomized, with a mean (SD) age of 45.2 (14.6) years and 132 (61.7%) women. The study was stopped for a low conditional power for benefit with no significant difference among the 4 groups for the primary end point. Patients who received usual care without supplementation achieved a 50% reduction in symptoms at a mean (SD) of 6.7 (4.4) days compared with 5.5 (3.7) days for the ascorbic acid group, 5.9 (4.9) days for the zinc gluconate group, and 5.5 (3.4) days for the group receiving both (overall P = .45). There was no significant difference in secondary outcomes among the treatment groups. Conclusions and Relevance: In this randomized clinical trial of ambulatory patients diagnosed with SARS-CoV-2 infection, treatment with high-dose zinc gluconate, ascorbic acid, or a combination of the 2 supplements did not significantly decrease the duration of symptoms compared with standard of care. Trial Registration: ClinicalTrials.gov Identifier: NCT04342728.


Subject(s)
Ascorbic Acid/therapeutic use , COVID-19/drug therapy , Dietary Supplements , Zinc/therapeutic use , Adult , Ambulatory Care , Antioxidants/therapeutic use , COVID-19/complications , Cough/drug therapy , Cough/etiology , Dyspnea/drug therapy , Dyspnea/etiology , Fatigue/drug therapy , Fatigue/etiology , Female , Fever/drug therapy , Fever/etiology , Gluconates/therapeutic use , Humans , Male , Middle Aged , SARS-CoV-2 , Severity of Illness Index , Standard of Care , Trace Elements/therapeutic use , Treatment Outcome
6.
Int J Infect Dis ; 99: 307-309, 2020 Oct.
Article in English | MEDLINE | ID: covidwho-548949

ABSTRACT

Coronavirus 2019 (COVID-19) is a pandemic with substantial mortality and no accepted therapy. We report here on four consecutive outpatients with clinical characteristics (CDC case definition) of and/or laboratory-confirmed COVID-19 who were treated with high dose zinc salt oral lozenges. All four patients experienced significant improvement in objective and symptomatic disease measures after one day of high dose therapy suggesting that zinc therapy was playing a role in clinical recovery. A mechanism for zinc's effects is proposed based on previously published studies on SARS- CoV-1, and randomized controlled trials assessing zinc shortening of common cold duration. The limited sample size and study design preclude a definitive statement about the effectiveness of zinc as a treatment for COVID-19 but suggest the variables to be addressed to confirm these initial findings in future trials.


Subject(s)
Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Gluconates/administration & dosage , Oxygen/administration & dosage , Pneumonia, Viral/drug therapy , Zinc Acetate/administration & dosage , Adult , COVID-19 , Coronavirus Infections/virology , Dyspnea/drug therapy , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2
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