Circulating pyruvate is a potent prognostic marker for critical COVID-19 outcomes.

Background: Coronavirus-19 (COVID-19) disease is driven by an unchecked immune response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus which alters host mitochondrial-associated mechanisms. Compromised mitochondrial health results in abnormal reprogramming of glucose metabolism, which can disrupt extracellular signalling. We hypothesized that examining mitochondrial energy-related signalling metabolites implicated in host immune response to SARS-CoV-2 infection would provide potential biomarkers for predicting the risk of severe COVID-19 illness. Methods: We used a semi-targeted serum metabolomics approach in 273 patients with different severity grades of COVID-19 recruited at the acute phase of the infection to determine the relative abundance of tricarboxylic acid (Krebs) cycle-related metabolites with known extracellular signaling properties (pyruvate, lactate, succinate and α-ketoglutarate). Abundance levels of energy-related metabolites were evaluated in a validation cohort (n=398) using quantitative fluorimetric assays. Results: Increased levels of four energy-related metabolites (pyruvate, lactate, a-ketoglutarate and succinate) were found in critically ill COVID-19 patients using semi-targeted and targeted approaches (p<0.05). The combined strategy proposed herein enabled us to establish that circulating pyruvate levels (p<0.001) together with body mass index (p=0.025), C-reactive protein (p=0.039), D-Dimer (p<0.001) and creatinine (p=0.043) levels, are independent predictors of critical COVID-19. Furthermore, classification and regression tree (CART) analysis provided a cut-off value of pyruvate in serum (24.54 µM; p<0.001) as an early criterion to accurately classify patients with critical outcomes. Conclusion: Our findings support the link between COVID-19 pathogenesis and immunometabolic dysregulation, and show that fluorometric quantification of circulating pyruvate is a cost-effective clinical decision support tool to improve patient stratification and prognosis prediction.

Presentation and outcomes of chronic kidney disease patients with COVID-19.

INTRODUCTION: COVID-19 is currently a global health issue and an important cause of mortality. Chronic kidney disease (CKD) is one of the risk factors for infection, morbidity and mortality by SARS-CoV-2. In our study, we aimed to evaluate the clinical presentation and outcomes of CKD patients with COVID-19, as well as identify predictors of mortality. METHODS: This was a retrospective study of CKD patients admitted in a tertiary-care Portuguese hospital between March and August of 2020. Variables were submitted to univariate and multivariate analysis to determine factors predictive of in-hospital mortality. RESULTS: 130 CKD patients were analyzed (median age 73.9 years, male 60.0%). Hypertension (81.5%), cardiovascular disease (36.2%), and diabetes (54.6%) were frequent conditions. Cough, dyspnea, fever and respiratory failure were also common. Almost 60% had anemia, 50% hypoalbuminemia, 13.8% hyperlactacidemia and 17% acidemia. Mean serum ferritin was 1531 µg/L, mean CRP 8.3 mg/dL and mean LDH 336.9 U/L. Most patients were treated with lopinavir/ritonavir, hydroxychloroquine or corticosteroids and only 2 with remdesivir. Eighty percent had acute kidney injury and 16.2% required intensive care unit admission. The 34 patients who died were older and more likely to have heart failure. They had higher neutrophils/lymphocytes ratio, ferritin, lactate, and LDH levels. Multivariate analysis identified an association between older age [OR 1.1 (CI 1.01-1.24), p=0.027], higher ferritin [OR 1.0 (CI 1.00-1.00), p=0.009] and higher LDH levels [OR 1.0 (CI 1.00-1.01), p=0.014] and mortality. CONCLUSION: In our cohort of CKD patients with COVID-19, older age, higher ferritin, and higher LDH levels were independent risk factors for mortality.

The impact of transient and persistent acute kidney injury in hospital mortality in COVID-19 patients.

INTRODUCTION: Acute kidney injury (AKI) has been described in Coronavirus Disease 2019 (COVID-19) patients and is considered a marker of disease severity and a negative prognostic factor for survival. In this study, the authors aimed to study the impact of transient and persistent acute kidney injury (pAKI) on in-hospital mortality in COVID-19 patients. METHODS: This was a retrospective observational study of patients hospitalized with COVID-19 in the Department of Medicine of the Centro Hospitalar Universitario Lisboa Norte, Lisbon, Portugal, between March 2020 and August 2020. A multivariate analysis was performed to predict AKI development and in-hospital mortality. RESULTS: Of 544 patients with COVID-19, 330 developed AKI: 166 persistent AKI (pAKI), 164 with transient AKI. AKI patients were older, had more previous comorbidities, had higher need to be medicated with RAAS inhibitors, had higher baseline serum creatine (SCr) (1.60 mg/dL vs 0.87 mg/dL), higher NL ratio, and more severe acidemia on hospital admission, and more frequently required admission in intensive care unit, mechanical ventilation, and vasopressor use. Patients with persistent AKI had higher SCr level (1.71 mg/dL vs 1.25 mg/dL) on hospital admission. In-hospital mortality was 14.0% and it was higher in AKI patients (18.5% vs 7.0%). CKD and serum ferritin were independent predictors of AKI. AKI did not predict mortality, but pAKI was an independent predictor of mortality, as was age and lactate level. CONCLUSION: pAKI was independently associated with in-hospital mortality in COVID-19 patients but its impact on long-term follow-up remains to be determined.

New Insights into the Identification of Metabolites and Cytokines Predictive of Outcome for Patients with Severe SARS-CoV-2 Infection Showed Similarity with Cancer.

SARS-CoV-2 infection is characterized by several clinical manifestations, ranging from the absence of symptoms to severe forms that necessitate intensive care treatment. It is known that the patients with the highest rate of mortality develop increased levels of proinflammatory cytokines, called the "cytokine storm", which is similar to inflammatory processes that occur in cancer. Additionally, SARS-CoV-2 infection induces modifications in host metabolism leading to metabolic reprogramming, which is closely linked to metabolic changes in cancer. A better understanding of the correlation between perturbed metabolism and inflammatory responses is necessary. We evaluated untargeted plasma metabolomics and cytokine profiling via 1H-NMR (proton nuclear magnetic resonance) and multiplex Luminex assay, respectively, in a training set of a limited number of patients with severe SARS-CoV-2 infection classified on the basis of their outcome. Univariate analysis and Kaplan-Meier curves related to hospitalization time showed that lower levels of several metabolites and cytokines/growth factors, correlated with a good outcome in these patients and these data were confirmed in a validation set of patients with similar characteristics. However, after the multivariate analysis, only the growth factor HGF, lactate and phenylalanine retained a significant prediction of survival. Finally, the combined analysis of lactate and phenylalanine levels correctly predicted the outcome of 83.3% of patients in both the training and the validation set. We highlighted that the cytokines and metabolites involved in COVID-19 patients' poor outcomes are similar to those responsible for cancer development and progression, suggesting the possibility of targeting them by repurposing anticancer drugs as a therapeutic strategy against severe SARS-CoV-2 infection.

The effects of adjunctive treatment with L-carnitine on monitoring laboratory variables in ICU patients: a double-blinded randomized controlled clinical trial.

BACKGROUND: Critically ill patients must be monitored constantly in intensive care units (ICUs). Among many laboratory variables, nutritional status indicators are a key role in the prognosis of diseases. We investigated the effects of L-carnitine adjunctive therapy on monitoring variables in critical illness. METHOD: A prospective, double-blind, randomized controlled trial was implemented in a medical ICU. Participants were 54 patients, aged > 18 years, with multiple conditions, randomly assigned to receive 3 g L-carnitine per day or placebo, along with enteral feeding, for 1 week. Primary outcomes included monitoring variables related to nutritional status. RESULT: Of 54 patients randomly assigned, 51 completed the trial. Serum albumin (Alb) (P-value: 0.001), total protein (P-value: 0.003), and calcium (Ca) (0.044) significantly increased in the intervention vs. control group. Alanine transaminase (ALT) (0.022), lactate (<0.001), creatinine (Cr) (0.005), and international normalized ratio (INR) (0.049) decreased meaningfully in the intervention vs. control group. CONCLUSION: L-Carnitine supplementation in critically ill patients can improve several parameters including INR, Cr, ALT, lactate, Ca, Alb, and total protein. TRIAL REGISTRATION: Iranian Registry of Clinical Trials IRCT 20151108024938N2. This trial was approved by the Research Ethics Committee of Mashhad University of Medical Sciences (registration code: IR.MUMS.fm.REC.1396.671) (available at https://en.irct.ir/trial/30748 , May 2018).

Fluid balance neutralization secured by hemodynamic monitoring versus protocolized standard of care in critically ill patients requiring continuous renal replacement therapy: study protocol of the GO NEUTRAL randomized controlled trial.

BACKGROUND: Fluid overload is associated with worse outcome in critically ill patients requiring continuous renal replacement therapy (CRRT). Net ultrafiltration (UFNET) allows precise control of the fluid removal but is frequently ceased due to hemodynamic instability episodes. However, approximately 50% of the hemodynamic instability episodes in ICU patients treated with CRRT are not associated with preload dependence (i.e., are not related to a decrease in cardiac preload), suggesting that volume removal is not responsible for these episodes of hemodynamic impairment. The use of advanced hemodynamic monitoring, comprising continuous cardiac output monitoring to repeatedly assess preload dependency, could allow securing UFNET to allow fluid balance control and prevent fluid overload. METHODS: The GO NEUTRAL trial is a multicenter, open-labeled, randomized, controlled, superiority trial with parallel groups and balanced randomization with a 1:1 ratio. The trial will enroll adult patients with acute circulatory failure treated with vasopressors and severe acute kidney injury requiring CRRT who already have been equipped with a continuous cardiac output monitoring device. After informed consent, patients will be randomized into two groups. The control group will receive protocolized fluid removal with an UFNET rate set to 0-25 ml h-1 between inclusion and H72 of inclusion. The intervention group will be treated with an UFNET rate set on the CRRT of at least 100 ml h-1 between inclusion and H72 of inclusion if hemodynamically tolerated based on a protocolized hemodynamic protocol aiming to adjust UFNET based on cardiac output, arterial lactate concentration, and preload dependence assessment by postural maneuvers, performed regularly during nursing rounds, and in case of a hemodynamic instability episode. The primary outcome of the study will be the cumulative fluid balance between inclusion and H72 of inclusion. Randomization will be generated using random block sizes and stratified based on fluid overload status at inclusion. The main outcome will be analyzed in the modified intention-to-treat population, defined as all alive patients at H72 of inclusion, based on their initial allocation group. DISCUSSION: We present in the present protocol all study procedures in regard to the achievement of the GO NEUTRAL trial, to prevent biased analysis of trial outcomes and improve the transparency of the trial result report. Enrollment of patients in the GO NEUTRAL trial has started on June 31, 2021, and is ongoing. TRIAL REGISTRATION: ClinicalTrials.gov NCT04801784. Registered on March 12, 2021, before the start of inclusion.

Characteristics and predictors of outcomes of critically Ill children with SARS-CoV-2 infection - the PICU experience.

OBJECTIVE: To describe the clinical characteristics, laboratory parameters, treatment, and predictors of an unfavorable outcome of critically ill children with SARS-CoV-2 infection. METHOD: This was a prospective observational study performed in a pediatric intensive care unit (PICU) of a tertiary care COVID referral hospital among critically ill children in the age group 1 month - 12 years admitted due to SARS-CoV-2 infection from June to December 2020. Demographic, clinical profile, pSOFA and PRISM III scores, laboratory parameters, treatment, and outcomes of the patients were recorded. Children who had a prolonged PICU stay (>14 days) or died were compared with those who were discharged from PICU within 14 days to assess predictors of unfavorable outcomes. RESULTS: PICU admission rate among hospitalized SARS-CoV-2 infected children was 22.1% (92/416). Infants comprised the majority of the ICU population. Invasive mechanical ventilation and inotropic support were required for 28.3% and 37% of patients, respectively. Remdesivir, IVIg, and steroids were administered to 15.2%, 26.1%, and 54.3% of the subjects, respectively. The mortality rate was 7.6 %. MIS-C patients were older, less comorbid, and required less ventilator support but more inotrope support than acute severe COVID-19 patients. Predictors of unfavorable outcomes were age < 1 year, fever duration > 5 days, respiratory distress, shock, comorbidity, elevated CRP (> 50 mg/L), procalcitonin (> 6 ng/L), D-dimer (> 6 µg/L) and arterial lactate (> 2 mmol/L). CONCLUSION: Critically ill children with unfavorable outcomes were predominantly infants, comorbid, prolonged fever, respiratory distress, shock and elevated inflammatory markers, D-dimer and lactate. These factors may be useful for watchful monitoring and early intervention.

Lactate dehydrogenase/albumin ratio as a prognostic factor in severe acute respiratory distress syndrome cases associated with COVID-19.

BACKGROUND: Patients with severe acute respiratory distress syndrome (ARDS) have high mortality rates; therefore, new biomarkers are necessary to predict the prognosis in the early stages. Serum lactate dehydrogenase (LDH) level is a specific marker of lung damage, but it is not sensitive because it is affected by several factors. This study aimed to determine whether the LDH/albumin ratio could be used as a prognostic biomarker in patients with severe ARDS due to COVID 19. METHODS: Tertiary intensive care unit (ICU) patients with severe ARDS and confirmed COVID-19 diagnosis between August 1, 2020, and October 31, 2021, were included. The demographic and clinical characteristics of the patients were recorded from the hospital databases, together with laboratory results on the day of admission to the ICU and the length of stay in the ICU and hospital. LDH/albumin, lactate/albumin, C-reactive protein (CRP)/albumin, and BUN/albumin ratios were calculated. Logistic regression analysis was performed to determine independent risk factors affecting mortality. RESULTS: Nine hundred and five patients hospitalized in a tertiary ICU were evaluated. Three hundred fifty-one patients with severe ARDS were included in this study. The mortality rate of the included patients was 61.8% (of 217/351). LDH/albumin, lactate/albumin, and BUN/albumin ratios were higher in the nonsurvivor group (P < .001). The area under the curve (AUC) from the receiver operating characteristic analysis that predicted in-hospital mortality was 0.627 (95% confidence intervals (CI): 0.574-0.678, P < .001) for the LDH/albumin ratio, 0.605 (95% CI: 0.551-0.656, P < .001) for lactate/albumin, and 0.638 (95% CI: 0.585-0.688, P < .001) for BUN/albumin. However, LDH/albumin ratio was independently associated with mortality in multivariate logistic regression analysis. CONCLUSION: LDH/albumin ratio can be used as an independent prognostic factor for mortality in patients with severe ARDS caused by COVID-19.

Influence of Manual Diaphragm Release Technique Combined with Inspiratory Muscle Training on Selected Persistent Symptoms in Men with Post-Covid-19 Syndrome: A Randomized Controlled Trial.

OBJECTIVE: To determine whether the addition of manual diaphragm release to an inspiratory muscle training programme is more  effective than inspiratory muscle training alone in reducing blood pressure, dyspnoea, fatigue, and aerobic performance capacity in men with post-COVID-19 syndrome. DESIGN: A prospective, randomized-controlled trial. SETTING: Chest Disease Department, Outpatient Clinic, Cairo University, Egypt. PARTICIPANTS: Fifty-two men with post-COVID-19 syndrome were allocated randomly to the study and control groups. INTERVENTION: The study group underwent diaphragm release plus inspiratory muscle training, whereas the control group received inspiratory muscle training only. OUTCOME MEASURES: All patients were assessed with the following measures at baseline and 6 weeks postintervention: maximum static inspiratory pressure for inspiratory muscle strength, peripheral arterial blood pressure, Modified Medical Research Council scale for dyspnoea, Fatigue Severity Scale, serum lactate level, and 6-min walk test distance for aerobic performance. RESULTS: All outcome measures showed a significant improvement in favour of the study group (p < 0.001) over the control group. However, maximum static inspiratory pressure increased significantly, by 48.17% (p < 0.001) in the study group with no significant change in the control group. CONCLUSION: Addition of manual diaphragm release to an inspiratory muscle training programme potentiates the role of inspiratory muscle training in the management of men with symptomatic post-COVID-19 syndrome.

Risk factors of a severe course of pediatric multi-system inflammatory syndrome temporally associated with COVID-19.

Pediatric multi-system inflammatory syndrome temporally associated with COVID-19 (PIMS-TS) is a serious complication of a previous SARS-CoV-2 infection. The disease causes multiple organ failure, but in some patients, a more severe course of the disease is observed. The treatment is multidirectional and depends on the severity and course of the disease, as some patients do not respond to the recommended treatment. The aim of this study was to identify laboratory risk factors affecting the more severe course of the disease and resistance to standard therapy. It is a single-center retrospective study considering 51 patients with PIMS-TS. Clinical features, laboratory results, and additional imaging tests data were taken into account. Fifty-one patients with PIMS-TS were hospitalized within a 16-month observation period. In the studied group, 26/51 children (51%) were girls. The mean age of patients was 7 years. Sex of the patient was not a risk factor for changes in cardiovascular system or severe course of the disease. Sixteen patients (31.3%) required transfer to the intensive care unit. Children with initially higher concentrations of NT-proBNP, troponin, creatinine, triglycerides, C-reactive protein, procalcitonin, ferritin, D-dimers and lower hematocrit, platelet count, lymphocytes, and ejection fraction should be strictly observed as they have a higher risk of severe course of the disease. CONCLUSIONS: Laboratory parameters especially markers of myocardial damage, markers of inflammation, blood count, as wells as biochemical parameters are significant risk indicators of severe course of PIMS -TS and their concentration can be defined as predictor of disease severity. WHAT IS KNOWN: • Pediatric multisystem inflammatory syndrome temporally associated with COVID-19 (PIMS-TS) is a serious complication of a previous SARS-CoV-2 infection in the group of pediatric patients • Course of the disease may be severe, which may cause long-term complications and the need for longitudinal patient care. WHAT IS NEW: • Children with higher concentrations of NT-proBNP, troponin, creatinine, TG, CRP, PCT, ferritin, D-dimers and lower hematocrit, PLT, lymphocytes, and EF have a higher risk of a severe course of the disease. • Patients with high concentration of NT-proBNP, troponin, CRP, lactates, ferritin, D-dimers, creatinine and a lower concentration of PLT, albumin, leukocytes; lymphopenia, hyponatremia are at risk for intravenous immunoglobulin resistance.

Factors influencing death in COVID-19 patients treated in the ICU: a single-centre, cross-sectional study.

BACKGROUND: This single-centre study investigated factors influencing death in coronavirus disease 2019 (COVID-19) patients treated in an intensive care unit (ICU). METHODS: Data of 113 consecutive patients with a severe form of COVID-19 infection, who completed their ICU stay in a large COVID-19-dedicated hospital in the Silesian Region of Poland during one year of the pandemic (between 10 March, 2020 and 10 March, 2021), were reviewed. Comprehensive comparison of all available ICU pre-admission, admission and treatment variables was performed. Variables that independently influenced ICU death were identified. RESULTS: ICU mortality in the whole group was 64.6%. Mean age was higher in non-survivors (64.6 ± 9.5 vs. 60.0 ± 12.8 years, P = 0.036), but the distribution of sex and body mass index was similar in both groups. Non-survivors had a marginally higher mean Charlson Comorbidity Index (5.9 ± 3.6 vs. 4.5 ± 4.1 points, P = 0.063), and significantly higher mean Clinical Frailty Score (4.8 ± 1.5 vs. 3.9 ± 1.4 points, P = 0.004), admission APACHE II score (22.9 ± 7.9 vs. 19.1 ± 7.8 points, P = 0.017) and SAPS II score (62.1 ± 18.1 vs. 54.0 ± 16.7 points, P = 0.023). Factors that independently influenced ICU death were limited to: admission total protein 2.0 ng mL-1 (OR = 11.3, P = 0.026) and lactate level > 2.0 mmol L-1 (OR = 4.2, P = 0.003) as well as Clinical Frailty Score ≥ 5 points (OR = 3.1, P = 0.021). CONCLUSIONS: The presence of low total protein, frailty and increased procalcitonin and lactate levels at ICU admission are associated with ICU death in patients with severe COVID-19 infection.

1H qNMR-Based Metabolomics Discrimination of Covid-19 Severity.

The coronavirus disease 2019 (Covid-19), which caused respiratory problems in many patients worldwide, led to more than 5 million deaths by the end of 2021. Experienced symptoms vary from mild to severe illness. Understanding the infection severity to reach a better prognosis could be useful to the clinics, and one study area to fulfill one piece of this biological puzzle is metabolomics. The metabolite profile and/or levels being monitored can help predict phenotype properties. Therefore, this study evaluated plasma metabolomes of 110 individual samples, 57 from control patients and 53 from recent positive cases of Covid-19 (IgM 98% reagent), representing mild to severe symptoms, before any clinical intervention. Polar metabolites from plasma samples were analyzed by quantitative 1H NMR. Glycerol, 3-aminoisobutyrate, formate, and glucuronate levels showed alterations in Covid-19 patients compared to those in the control group (Tukey's HSD p-value cutoff = 0.05), affecting the lactate, phenylalanine, tyrosine, and tryptophan biosynthesis and d-glutamine, d-glutamate, and glycerolipid metabolisms. These metabolic alterations show that SARS-CoV-2 infection led to disturbance in the energetic system, supporting the viral replication and corroborating with the severe clinical conditions of patients. Six polar metabolites (glycerol, acetate, 3-aminoisobutyrate, formate, glucuronate, and lactate) were revealed by PLS-DA and predicted by ROC curves and ANOVA to be potential prognostic metabolite panels for Covid-19 and considered clinically relevant for predicting infection severity due to their straight roles in the lipid and energy metabolism. Thus, metabolomics from samples of Covid-19 patients is a powerful tool for a better understanding of the disease mechanism of action and metabolic consequences of the infection in the human body and may corroborate allowing clinicians to intervene quickly according to the needs of Covid-19 patients.

Predictors of venous thromboembolism in COVID-19 patients: results of the COVID-19 Brazilian Registry.

Previous studies that assessed risk factors for venous thromboembolism (VTE) in COVID-19 patients have shown inconsistent results. Our aim was to investigate VTE predictors by both logistic regression (LR) and machine learning (ML) approaches, due to their potential complementarity. This cohort study of a large Brazilian COVID-19 Registry included 4120 COVID-19 adult patients from 16 hospitals. Symptomatic VTE was confirmed by objective imaging. LR analysis, tree-based boosting, and bagging were used to investigate the association of variables upon hospital presentation with VTE. Among 4,120 patients (55.5% men, 39.3% critical patients), VTE was confirmed in 6.7%. In multivariate LR analysis, obesity (OR 1.50, 95% CI 1.11-2.02); being an ex-smoker (OR 1.44, 95% CI 1.03-2.01); surgery ≤ 90 days (OR 2.20, 95% CI 1.14-4.23); axillary temperature (OR 1.41, 95% CI 1.22-1.63); D-dimer ≥ 4 times above the upper limit of reference value (OR 2.16, 95% CI 1.26-3.67), lactate (OR 1.10, 95% CI 1.02-1.19), C-reactive protein levels (CRP, OR 1.09, 95% CI 1.01-1.18); and neutrophil count (OR 1.04, 95% CI 1.005-1.075) were independent predictors of VTE. Atrial fibrillation, peripheral oxygen saturation/inspired oxygen fraction (SF) ratio and prophylactic use of anticoagulants were protective. Temperature at admission, SF ratio, neutrophil count, D-dimer, CRP and lactate levels were also identified as predictors by ML methods. By using ML and LR analyses, we showed that D-dimer, axillary temperature, neutrophil count, CRP and lactate levels are risk factors for VTE in COVID-19 patients.

Danshensu alleviates pseudo-typed SARS-CoV-2 induced mouse acute lung inflammation.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can induce acute inflammatory response like acute lung inflammation (ALI) or acute respiratory distress syndrome, leading to severe progression and mortality. Therapeutics for treatment of SARS-CoV-2-triggered respiratory inflammation are urgent to be discovered. Our previous study shows that Salvianolic acid C potently inhibits SARS-CoV-2 infection. In this study, we investigated the antiviral effects of a Salvia miltiorrhiza compound, Danshensu, in vitro and in vivo, including the mechanism of S protein-mediated virus attachment and entry into target cells. In authentic and pseudo-typed virus assays in vitro, Danshensu displayed a potent antiviral activity against SARS-CoV-2 with EC50 of 0.97 µM, and potently inhibited the entry of SARS-CoV-2 S protein-pseudo-typed virus (SARS-CoV-2 S) into ACE2-overexpressed HEK-293T cells (IC50 = 0.31 µM) and Vero-E6 cell (IC50 = 4.97 µM). Mice received SARS-CoV-2 S via trachea to induce ALI, while the VSV-G treated mice served as controls. The mice were administered Danshensu (25, 50, 100 mg/kg, i.v., once) or Danshensu (25, 50, 100 mg·kg-1·d-1, oral administration, for 7 days) before SARS-CoV-2 S infection. We showed that SARS-CoV-2 S infection induced severe inflammatory cell infiltration, severely damaged lung tissue structure, highly expressed levels of inflammatory cytokines, and activated TLR4 and hyperphosphorylation of the NF-κB p65; the high expression of angiotensinogen (AGT) and low expression of ACE2 at the mRNA level in the lung tissue were also observed. Both oral and intravenous pretreatment with Danshensu dose-dependently alleviated the pathological alterations in mice infected with SARS-CoV-2 S. This study not only establishes a mouse model of pseudo-typed SARS-CoV-2 (SARS-CoV-2 S) induced ALI, but also demonstrates that Danshensu is a potential treatment for COVID-19 patients to inhibit the lung inflammatory response.

Three salvianolic acids inhibit 2019-nCoV spike pseudovirus viropexis by binding to both its RBD and receptor ACE2.

Since December 2019, the new coronavirus (also known as severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2, 2019-nCoV])-induced disease, COVID-19, has spread rapidly worldwide. Studies have reported that the traditional Chinese medicine Salvia miltiorrhiza possesses remarkable antiviral properties; however, the anti-coronaviral activity of its main components, salvianolic acid A (SAA), salvianolic acid B (SAB), and salvianolic acid C (SAC) is still debated. In this study, we used Cell Counting Kit-8 staining and flow cytometry to evaluate the toxicity of SAA, SAB, and SAC on ACE2 (angiotensin-converting enzyme 2) high-expressing HEK293T cells (ACE2h cells). We found that SAA, SAB, and SAC had a minor effect on the viability of ACE2h cells at concentrations below 100 µM. We further evaluated the binding capacity of SAA, SAB, and SAC to ACE2 and the spike protein of 2019-nCoV using molecular docking and surface plasmon resonance. They could bind to the receptor-binding domain (RBD) of the 2019-nCoV with a binding constant (KD ) of (3.82 ± 0.43) e-6 M, (5.15 ± 0.64)e-7 M, and (2.19 ± 0.14)e-6 M; and bind to ACE2 with KD (4.08 ± 0.61)e-7 M, (2.95 ± 0.78)e-7 M, and (7.32 ± 0.42)e-7 M, respectively. As a result, SAA, SAB, and SAC were determined to inhibit the entry of 2019-nCoV Spike pseudovirus with an EC50 of 11.31, 6.22, and 10.14 µM on ACE2h cells, respectively. In conclusion, our study revealed that three Salvianolic acids can inhibit the entry of 2019-nCoV spike pseudovirus into ACE2h cells by binding to the RBD of the 2019-nCoV spike protein and ACE2 protein.

In silico drug discovery of major metabolites from spices as SARS-CoV-2 main protease inhibitors.

Coronavirus Disease 2019 (COVID-19) is an infectious illness caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), originally identified in Wuhan, China (December 2019) and has since expanded into a pandemic. Here, we investigate metabolites present in several common spices as possible inhibitors of COVID-19. Specifically, 32 compounds isolated from 14 cooking seasonings were examined as inhibitors for SARS-CoV-2 main protease (Mpro), which is required for viral multiplication. Using a drug discovery approach to identify possible antiviral leads, in silico molecular docking studies were performed. Docking calculations revealed a high potency of salvianolic acid A and curcumin as Mpro inhibitors with binding energies of -9.7 and -9.2 kcal/mol, respectively. Binding mode analysis demonstrated the ability of salvianolic acid A and curcumin to form nine and six hydrogen bonds, respectively with amino acids proximal to Mpro's active site. Stabilities and binding affinities of the two identified natural spices were calculated over 40 ns molecular dynamics simulations and compared to an antiviral protease inhibitor (lopinavir). Molecular mechanics-generalized Born surface area energy calculations revealed greater salvianolic acid A affinity for the enzyme over curcumin and lopinavir with energies of -44.8, -34.2 and -34.8 kcal/mol, respectively. Using a STRING database, protein-protein interactions were identified for salvianolic acid A included the biochemical signaling genes ACE, MAPK14 and ESR1; and for curcumin, EGFR and TNF. This study establishes salvianolic acid A as an in silico natural product inhibitor against the SARS-CoV-2 main protease and provides a promising inhibitor lead for in vitro enzyme testing.

Biosynthesis of medicinal tropane alkaloids in yeast.

Tropane alkaloids from nightshade plants are neurotransmitter inhibitors that are used for treating neuromuscular disorders and are classified as essential medicines by the World Health Organization1,2. Challenges in global supplies have resulted in frequent shortages of these drugs3,4. Further vulnerabilities in supply chains have been revealed by events such as the Australian wildfires5 and the COVID-19 pandemic6. Rapidly deployable production strategies that are robust to environmental and socioeconomic upheaval7,8 are needed. Here we engineered baker's yeast to produce the medicinal alkaloids hyoscyamine and scopolamine, starting from simple sugars and amino acids. We combined functional genomics to identify a missing pathway enzyme, protein engineering to enable the functional expression of an acyltransferase via trafficking to the vacuole, heterologous transporters to facilitate intracellular routing, and strain optimization to improve titres. Our integrated system positions more than twenty proteins adapted from yeast, bacteria, plants and animals across six sub-cellular locations to recapitulate the spatial organization of tropane alkaloid biosynthesis in plants. Microbial biosynthesis platforms can facilitate the discovery of tropane alkaloid derivatives as new therapeutic agents for neurological disease and, once scaled, enable robust and agile supply of these essential medicines.