N-Acetylcysteine and Other Sulfur-Donors as a Preventative and Adjunct Therapy for COVID-19

COVID-19 vaccine adverse events: Evaluating the pathophysiology with an emphasis on sulfur metabolism and endotheliopathy

In this narrative review, we assess the pathophysiology of severe adverse events that presented after vaccination with DNA and mRNA vaccines against COVID-19. The focus is on the perspective of an undersulfated and degraded glycocalyx, considering its impact on immunomodulation, inflammatory responses, coagulation and oxidative stress. The paper explores various factors that lead to glutathione and inorganic sulfate depletion and their subsequent effect on glycocalyx sulfation and other metabolites, including hormones. Components of COVID-19 vaccines, such as DNA and mRNA material, spike protein antigen and lipid nanoparticles, are involved in possible cytotoxic effects. The common thread connecting these adverse events is endotheliopathy or glycocalyx degradation, caused by depleted glutathione and inorganic sulfate levels, shear stress from circulating nanoparticles, aggregation and formation of protein coronas; leading to imbalanced immune responses and chronic release of pro-inflammatory cytokines, ultimately resulting in oxidative stress and systemic inflammatory response syndrome. By understanding the underlying pathophysiology of severe adverse events, better treatment options can be explored.

MS4A1-PTGS2 axis induces taurine metabolic reprogramming to exacerbate abdominal aortic aneurysm progression

This study unveils the pivotal roles of taurine metabolic reprogramming and its implications in the development and progression of Abdominal Aortic Aneurysm (AAA). Leveraging an integrated approach that combines single-cell RNA sequencing (scRNA-seq) and Weighted Gene Co-expression Network Analysis (WGCNA), our research investigates the intricate transcriptional and gene expression dynamics crucial to AAA. Our findings uniquely link metabolic shifts to the integrity of the extracellular matrix (ECM) and the functionality of smooth muscle cells (SMCs), key elements in the pathology of AAA. Utilizing scRNA-seq data from a mouse model (GSE152583 dataset), we identified critical alterations in cellular composition during AAA progression, particularly highlighting shifts in fibroblasts and inflammatory cells. Concurrently, WGCNA of human AAA tissue samples has outlined distinct gene expression patterns correlated with disease severity and progression, offering comprehensive insights into both molecular and cellular disease mechanisms. Moreover, this study introduces innovative metabolic profiling techniques to identify differential metabolites in AAA, integrating extensive metabolomic analyses with pathway enrichment strategies. This novel approach has pinpointed potential biomarkers and therapeutic targets, notably within taurine metabolism pathways, crucial for crafting non-surgical interventions. By merging state-of-the-art bioinformatics with thorough molecular analysis, our study not only enhances the understanding of AAA's complex pathophysiology but also catalyzes the development of targeted therapeutic strategies. This research represents a significant advancement in the molecular characterization of AAA, with substantial implications for its future diagnosis and treatment strategies.

Malnutrition elevates delirium and ICU stay among critically ill older adult COVID-19 patients

Background and aim

Malnutrition among intensive care unit (ICU) patients is associated with a higher risk of mortality and prolonged hospitalization. However, the influence of malnutrition on severe outcomes of ICU patients with coronavirus disease 2019 (COVID-19) is unclear. By evaluating the effect of malnutrition on the outcomes of COVID-19 in the ICU in older adult patients, this study will contribute to new knowledge of assessing the nutritional status and recovery of these patients.

Methods

In the current single center prospective study, 310 critically ill COVID-19 patients with an age range of ≥65 years were recruited. Data on demographic characteristics, laboratory parameters, comorbidities, medications, and types of mechanical ventilation were collected in the first 24 h of ICU admission. Malnutrition was defined based on the two-step approach of the Global Leadership Initiative on Malnutrition (GLIM) scale at baseline. During the 45 days after the baseline, we collected data on delirium incidence, mortality, invasive mechanical ventilation (IMV) requirement, length of ICU and hospital admission, and re-hospitalization.

Results

In this study, the prevalence of malnutrition was 63.4% among critically ill COVID-19 patients. During the 45-day follow-up, 190 (61.3%) COVID-19 deaths were recorded among the baseline 310 patients. After controlling for potential confounders, malnutrition was associated with an increased risk of delirium so malnourished COVID-19 patients had a significantly 35% higher risk of delirium than those without malnutrition (HR: 1.35, 95% CI: 1.01-1.83). Such a significant association was not for COVID-19 mortality and IMV requirement. In addition, malnutrition was associated with a significantly 84% greater odds of prolonged ICU admission (OR: 1.84, 95% CI: 1.09-3.10). No significant association was seen between malnutrition and re-hospitalization and also prolonged hospital admission.

Conclusion

Malnutrition was associated with an increased risk of delirium and prolonged ICU admission among critically ill older adult COVID-19 patients. Prevention, diagnosis, and treatment of malnutrition could be a key component in improving outcomes in these patients.

Protective role of N-acetylcysteine and Sulodexide on endothelial cells exposed on patients' serum after SARS-CoV-2 infection

Severe acute respiratory syndrome coronavirus-2 causes hyperinflammation and activation of coagulation cascade and, as a result, aggravates endothelial cell dysfunction. N-acetylcysteine and Sulodexide have been found to mitigate endothelial damage. The influence on coronary artery endothelial cells of serum collected after 4 ± 1 months from coronavirus infection was studied. The concentrations of serum samples of interleukin 6, von Willebrand Factor, tissue Plasminogen Activator, and Plasminogen Activator Inhibitor-1 were studied. The cultures with serum of patients after coronavirus infection were incubated with N-acetylcysteine and Sulodexide to estimate their potential protective role. The blood inflammatory parameters were increased in the group of cultures incubated with serum from patients after coronavirus infection. Supplementation of the serum from patients after coronavirus infection with N-acetylcysteine or Sulodexide reduced the synthesis of interleukin 6 and von Willebrand Factor. No changes in the synthesis of tissue Plasminogen Activator were observed. N-acetylcysteine reduced the synthesis of Plasminogen Activator Inhibitor-1. N-acetylcysteine and Sulodexide increased the tPA/PAI-1 ratio. N-acetylcysteine may have a role in reducing the myocardial injury occurring in the post-COVID-19 syndrome. Sulodexide can also play a protective role in post-COVID-19 patients.

Effects of Sulforaphane on SARS‑CoV‑2 infection and NF‑κB dependent expression of genes involved in the COVID‑19 'cytokine storm'

Since its spread at the beginning of 2020, the coronavirus disease 2019 (COVID‑19) pandemic represents one of the major health problems. Despite the approval, testing, and worldwide distribution of anti‑severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) vaccines, the development of specific antiviral agents targeting the SARS‑CoV‑2 life cycle with high efficiency, and/or interfering with the associated 'cytokine storm', is highly required. A recent study, conducted by the authors' group indicated that sulforaphane (SFN) inhibits the expression of IL‑6 and IL‑8 genes induced by the treatment of IB3‑1 bronchial cells with a recombinant spike protein of SARS‑CoV‑2. In the present study, the ability of SFN to inhibit SARS‑CoV‑2 replication and the expression of pro‑inflammatory genes encoding proteins of the COVID‑19 'cytokine storm' was evaluated. SARS‑CoV‑2 replication was assessed in bronchial epithelial Calu‑3 cells. Moreover, SARS‑CoV‑2 replication and expression of pro‑inflammatory genes was evaluated by reverse transcription quantitative droplet digital PCR. The effects on the expression levels of NF‑κB were assessed by western blotting. Molecular dynamics simulations of NF‑kB/SFN interactions were conducted with Gromacs 2021.1 software under the Martini 2 CG force field. Computational studies indicated that i) SFN was stably bound with the NF‑κB monomer; ii) a ternary NF‑kB/SFN/DNA complex was formed; iii) the SFN interacted with both the protein and the nucleic acid molecules modifying the binding mode of the latter, and impairing the full interaction between the NF‑κB protein and the DNA molecule. This finally stabilized the inactive complex. Molecular studies demonstrated that SFN i) inhibits the SARS‑CoV‑2 replication in infected Calu‑3 cells, decreasing the production of the N‑protein coding RNA sequences, ii) decreased NF‑κB content in SARS‑CoV‑2 infected cells and inhibited the expression of NF‑kB‑dependent IL‑1β and IL‑8 gene expression. The data obtained in the present study demonstrated inhibitory effects of SFN on the SARS‑CoV‑2 life cycle and on the expression levels of the pro‑inflammatory genes, sustaining the possible use of SFN in the management of patients with COVID‑19.

N-acetylcysteine efficacy in patients hospitalized with COVID-19 pneumonia: a systematic review and meta-analysis

BACKGROUND

N-acetylcysteine (NAC) is a mucolytic agents with anti-inflammatory properties that has been suggested as an adjunctive therapy in patients with COVID-19 pneumonia.

OBJECTIVES

We conducted a systematic review and meta-analysis to evaluate available evidence on the possible beneficial effects of NAC on SARS-CoV-2 infection.

METHODS

In September 2022, we conducted a comprehensive search on Pubmed/Medline and Embase on randomized controlled trials (RCTs) and observational studies on NAC in patients with COVID-19 pneumonia. Study selection, data extraction and risk of bias assessment was performed by two independent authors. RCTs and observational studies were analyzed separately.

RESULTS

We included 3 RCTs and 5 non-randomized studies on the efficacy of NAC in patients with COVID-19, enrolling 315 and 20826 patients respectively. Regarding in-hospital mortality, the summary effect of all RCTs was OR: 0.85 (95% CI: 0.43 to 1.67, I²=0%) and for non-randomized studies OR: 1.02 (95% CI: 0.47 to 2.23, I²=91%). Need for ICU admission was only reported by 1 RCT (OR: 0.86, 95% CI:0.44-1.69, p=0.66), while all included RCTs reported need for invasive ventilation (OR:0.91, 95% CI:0.54 to 1.53, I²=0). Risk of bias was low for all included RCTs, but certainty of evidence was very low for all outcomes due to serious imprecision and indirectness.

CONCLUSION

The certainty of evidence in the included studies was very low, thus recommendations for clinical practice cannot be yet made. For all hard clinical outcomes point estimates in RCTs are close to the line of no effect, while observational studies have a high degree of heterogeneity with some of them suggesting favorable results in patients receiving NAC. More research is warranted to insure that NAC is both effective and safe in patients with COVID-19 pneumonia.

N-acetylcysteine as adjuvant therapy for hospitalized Covid-19 patients: A single-center prospective cohort study

Background

Whilst over two years have passed since the COVID-19 pandemic's emergence, the proper management of the disease remains challenging. N-acetylcysteine (NAC) as a potentially effective therapeutic option has been suggested by studies, while the exact clinical role of this agent is yet to be evaluated.

Methods

This prospective case-control study was conducted in a major referral respiratory center in Tehran, Iran. We enrolled 217 patients treated with an intravenous daily dose of 1500 mg NAC as a case group; and 245 control patients who did not receive NAC. Two groups were matched based on other treatments, socio-demographics, medical history, and comorbidities.

Results

After ten days of adjuvant therapy with NAC, patients in the NAC group and control group had median room-air SpO2 of 91% and 88%, respectively (P=0.02). Also, the SpO2 to FiO2 ratio had a median of 463 and 421 in the case and control groups, respectively (P=0.01). Furthermore, the case group's hospitalization period was three days shorter (P=0.002). Further, cough, dyspnea, and decreased appetite were reported to have a significantly lower incidence in the case group (P=0.03, 0.001, 0.008).

Conclusion

We showed that a daily intravenous dose of NAC in hospitalized COVID-19 patients could shorten the hospital stay and improve some clinical symptoms; however, it does not remarkably improve the risk of ICU admission and the 28 days in-hospital mortality rate.

Does the use of cysteine-rich whey protein supplements (Inmunocal®) improve the health well-being of COVID-19 patients? A qualitative study

<b>Introduction:</b> In the context of SARS-CoV-2 infection, it has been proposed that oxidative stress may contribute to the management of COVID-19 severity. The impact on the well-being of patients with COVID-19 using cysteine-providing supplements has not yet been evaluated and there is a need to understand the benefits and limitations they may offer.<br /> <b>Aim:</b> The aim of this study is to understand the experiences of improved well-being with cysteine-rich whey protein supplementation (Immunocal®) in patients with COVID-19.<br /> <b>Methods:</b> A qualitative study was conducted by conducting semi-structured interviews with four participants taking Immunocal® while they had COVID-19. Participants were randomly recruited through internet networking. Ethical approval was obtained from the University ethics committee. Participants were informed of the study objectives two days in advance and consent was obtained before interviews began. We used the 16-item “Use of Immunocal supplement for COVID-19” (USIC-19) questionnaire to inquire about COVID-19 behavior (time of illness, symptoms, and severity of illness) and the experience of using the supplement during illness. Confidentiality was maintained throughout this study.<br /> <b>Results:</b> All participants presented mild discomfort such as headache, weakness, and tiredness when they had COVID-19 impacting most of them emotionally. The use of Immunocal® produced a partial improvement in all patients as only two continued to experience fatigue. Immunocal® improved the mood (50%) and physical health of the participants. In addition, participants reported that the supplement was recommended and dosed primarily by a consultant and that they did not feel hesitant to use it because of previous experiences of friends and family. The daily dosage of half of the participants was two sachets and all felt the need to consume the supplement which resulted in daily use.<br /> <b>Conclusion:</b> Following the daily dosage indications of the consultants, the participants who have consumed Inmunocal® have presented a partial improvement of the symptoms related to COVID-19, however, they feel the need to consume the supplement daily to improve their quality of life.