Immunomodulatory therapy for severe influenza

A panel of janus kinase inhibitors identified with anti-inflammatory effects protect mice from lethal influenza virus infection

Influenza remains a significant threat to public health. In severe cases, excessive inflammation can lead to severe pneumonia or acute respiratory distress syndrome, contributing to patient morbidity and mortality. While antivirals can be effective if administered early, current anti-inflammatory drugs have limited success in treating severe cases. Therefore, discovering new anti-inflammatory agents to inhibit influenza-related inflammatory diseases is crucial. Herein, we screened a drug library with known targets using a human monocyte U937 infected with the influenza virus to identify novel anti-inflammatory agents. We also evaluated the anti-inflammatory effects of the hit compounds in an influenza mouse model. Our research revealed that JAK inhibitors exhibited a higher hit rate and more potent inhibition effect than inhibitors targeting other drug targets in vitro. Of the 22 JAK inhibitors tested, 15 exhibited robust anti-inflammatory activity against influenza virus infection in vitro. Subsequently, we evaluated the efficacy of 10 JAK inhibitors using an influenza mouse model and observed that seven provided protection ranging from 40% to 70% against lethal influenza virus infection. We selected oclacitinib as a representative compound for an extensive study to further investigate the in vivo therapeutic potential of JAK inhibitors for severe influenza-associated inflammation. Our results revealed that oclacitinib effectively suppressed neutrophil and macrophage infiltration, reduced pro-inflammatory cytokine production, and ultimately mitigated lung injury in mice infected with lethal influenza virus without impacting viral titer. These findings suggest that JAK inhibitors can modulate immune responses to influenza virus infection and may serve as potential treatments for influenza.IMPORTANCEAntivirals exhibit limited efficacy in treating severe influenza when not administered promptly during the infection. Current steroidal and nonsteroidal anti-inflammatory drugs demonstrate restricted effectiveness against severe influenza or are associated with significant side effects. Therefore, there is an urgent need for novel anti-inflammatory agents that possess high potency and minimal adverse reactions. In this study, 15 JAK inhibitors were identified through a screening process based on their anti-inflammatory activity against influenza virus infection in vitro. Remarkably, 7 of the 10 selected inhibitors exhibited protective effects against lethal influenza virus infection in mice, thereby highlighting the potential therapeutic value of JAK inhibitors for treating influenza.

Developmental Impacts of Epigenetics and Metabolism in COVID-19

Developmental biology is intricately regulated by epigenetics and metabolism but the mechanisms are not completely understood. The situation becomes even more complicated during diseases where all three phenomena are dysregulated. A salient example is COVID-19, where the death toll exceeded 6.96 million in 4 years, while the virus continues to mutate into different variants and infect people. Early evidence during the pandemic showed that the host's immune and inflammatory responses to COVID-19 (like the cytokine storm) impacted the host's metabolism, causing damage to the host's organs and overall physiology. The involvement of angiotensin-converting enzyme 2 (ACE2), the pivotal host receptor for the SARS-CoV-2 virus, was identified and linked to epigenetic abnormalities along with other contributing factors. Recently, studies have revealed stronger connections between epigenetics and metabolism in COVID-19 that impact development and accelerate aging. Patients manifest systemic toxicity, immune dysfunction and multi-organ failure. Single-cell multiomics and other state-of-the-art high-throughput studies are only just beginning to demonstrate the extent of dysregulation and damage. As epigenetics and metabolism directly impact development, there is a crucial need for research implementing cutting-edge technology, next-generation sequencing, bioinformatics analysis, the identification of biomarkers and clinical trials to help with prevention and therapeutic interventions against similar threats in the future.

Rationale for combined therapies in severe-to-critical COVID-19 patients

An unprecedented global social and economic impact as well as a significant number of fatalities have been brought on by the coronavirus disease 2019 (COVID-19), produced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Acute SARS-CoV-2 infection can, in certain situations, cause immunological abnormalities, leading to an anomalous innate and adaptive immune response. While most patients only experience mild symptoms and recover without the need for mechanical ventilation, a substantial percentage of those who are affected develop severe respiratory illness, which can be fatal. The absence of effective therapies when disease progresses to a very severe condition coupled with the incomplete understanding of COVID-19's pathogenesis triggers the need to develop innovative therapeutic approaches for patients at high risk of mortality. As a result, we investigate the potential contribution of promising combinatorial cell therapy to prevent death in critical patients.

n-3 Polyunsaturated Fatty Acids Modulate LPS-Induced ARDS and the Lung-Brain Axis of Communication in Wild-Type versus Fat-1 Mice Genetically Modified for Leukotriene B4 Receptor 1 or Chemerin Receptor 23 Knockout

Specialized pro-resolving mediators (SPMs) and especially Resolvin E1 (RvE1) can actively terminate inflammation and promote healing during lung diseases such as acute respiratory distress syndrome (ARDS). Although ARDS primarily affects the lung, many ARDS patients also develop neurocognitive impairments. To investigate the connection between the lung and brain during ARDS and the therapeutic potential of SPMs and its derivatives, fat-1 mice were crossbred with RvE1 receptor knockout mice. ARDS was induced in these mice by intratracheal application of lipopolysaccharide (LPS, 10 µg). Mice were sacrificed at 0 h, 4 h, 24 h, 72 h, and 120 h post inflammation, and effects on the lung, liver, and brain were assessed by RT-PCR, multiplex, immunohistochemistry, Western blot, and LC-MS/MS. Protein and mRNA analyses of the lung, liver, and hypothalamus revealed LPS-induced lung inflammation increased inflammatory signaling in the hypothalamus despite low signaling in the periphery. Neutrophil recruitment in different brain structures was determined by immunohistochemical staining. Overall, we showed that immune cell trafficking to the brain contributed to immune-to-brain communication during ARDS rather than cytokines. Deficiency in RvE1 receptors and enhanced omega-3 polyunsaturated fatty acid levels (fat-1 mice) affect lung-brain interaction during ARDS by altering profiles of several inflammatory and lipid mediators and glial activity markers.

Investigational Use of Mesenchymal Stem/Stromal Cells and Their Secretome as Add-On Therapy in Severe Respiratory Virus Infections: Challenges and Perspectives

Serious manifestations of respiratory virus infections such as influenza and coronavirus disease 2019 (COVID-19) are associated with a dysregulated immune response and systemic inflammation. Treating the immunological/inflammatory dysfunction with glucocorticoids, Janus kinase inhibitors, and monoclonal antibodies against the interleukin-6 receptor has significantly reduced the risk of respiratory failure and death in hospitalized patients with severe COVID-19, but the proportion of those requiring invasive mechanical ventilation (IMV) and dying because of respiratory failure remains elevated. Treatment of severe influenza-associated pneumonia and acute respiratory distress syndrome (ARDS) with available immunomodulators and anti-inflammatory compounds is still not recommended. New therapies are therefore needed to reduce the use of IMV and the risk of death in hospitalized patients with rapidly increasing oxygen demand and systemic inflammation who do not respond to the current standard of care. This paper provides a critical assessment of the published clinical trials that have tested the investigational use of intravenously administered allogeneic mesenchymal stem/stromal cells (MSCs) and MSC-derived secretome with putative immunomodulatory/antiinflammatory/regenerative properties as add-on therapy to improve the outcome of these patients. Increased survival rates are reported in 5 of 12 placebo-controlled or open-label comparative trials involving patients with severe and critical COVID-19 and in the only study concerning patients with influenza-associated ARDS. Results are encouraging but inconclusive for the following reasons: small number of patients tested in each trial; differences in concomitant treatments and respiratory support; imbalances between study arms; differences in MSC source, MSC-derived product, dosing and starting time of the investigational therapy; insufficient/inappropriate reporting of clinical data. Solutions are proposed for improving the clinical development plan, with the aim of facilitating regulatory approval of the MSC-based investigational therapy for life-threatening respiratory virus infections in the future. Major issues are the absence of a biomarker predicting responsiveness to MSCs and MSC-derived secretome and the lack of pharmacoeconomic evaluations.

Combination therapy with predicted body weight-based dexamethasone, remdesivir, and baricitinib in patients with COVID-19 pneumonia: A single-center retrospective cohort study during 5th wave in Japan

BACKGROUND

Dexamethasone, remdesivir, and baricitinib reduce mortality in patients with coronavirus disease 2019 (COVID-19). A single-arm study using combination therapy with all three drugs reported low mortality in patients with severe COVID-19. In this clinical setting, whether dexamethasone administered as a fixed dose of 6 mg has sufficient inflammatory modulation effects of reducing lung injury has been debated.

METHODS

This single-center retrospective study was conducted to compare the treatment strategies/management in different time periods. A total of 152 patients admitted with COVID-19 pneumonia who required oxygen therapy were included in this study. A predicted body weight (PBW)-based dose of dexamethasone with remdesivir and baricitinib was administered between May and June 2021. After this period, patients were administered a fixed dose of dexamethasone at 6.6 mg/day between July and August 2021. The additional respiratory support frequency of high-flow nasal cannula, noninvasive ventilation, and mechanical ventilation was analyzed. Moreover, the Kaplan-Meier method was used to analyze the duration of oxygen therapy and the 30-day discharge alive rate, and they were compared using the log-rank test.

RESULTS

Intervention and prognostic comparisons were performed in 64 patients with PBW-based and 88 with fixed-dose groups. The frequency of infection or additional respiratory support did not differ statistically. The cumulative incidence of being discharged alive or oxygen-free rate within 30 days did not differ between the groups.

CONCLUSIONS

In patients with COVID-19 pneumonia who required oxygen therapy, combination therapy with PBW-based dexamethasone, remdesivir, and baricitinib might not shorten the hospital stay's length or oxygen therapy's duration.

Aerosolized nicotine from e-cigarettes alters gene expression, increases lung protein permeability, and impairs viral clearance in murine influenza infection

E-cigarette use has rapidly increased as an alternative means of nicotine delivery by heated aerosolization. Recent studies demonstrate nicotine-containing e-cigarette aerosols can have immunosuppressive and pro-inflammatory effects, but it remains unclear how e-cigarettes and the constituents of e-liquids may impact acute lung injury and the development of acute respiratory distress syndrome caused by viral pneumonia. Therefore, in these studies, mice were exposed one hour per day over nine consecutive days to aerosol generated by the clinically-relevant tank-style Aspire Nautilus aerosolizing e-liquid containing a mixture of vegetable glycerin and propylene glycol (VG/PG) with or without nicotine. Exposure to the nicotine-containing aerosol resulted in clinically-relevant levels of plasma cotinine, a nicotine-derived metabolite, and an increase in the pro-inflammatory cytokines IL-17A, CXCL1, and MCP-1 in the distal airspaces. Following the e-cigarette exposure, mice were intranasally inoculated with influenza A virus (H1N1 PR8 strain). Exposure to aerosols generated from VG/PG with and without nicotine caused greater influenza-induced production in the distal airspaces of the pro-inflammatory cytokines IFN-γ, TNFα, IL-1β, IL-6, IL-17A, and MCP-1 at 7 days post inoculation (dpi). Compared to the aerosolized carrier VG/PG, in mice exposed to aerosolized nicotine there was a significantly lower amount of Mucin 5 subtype AC (MUC5AC) in the distal airspaces and significantly higher lung permeability to protein and viral load in lungs at 7 dpi with influenza. Additionally, nicotine caused relative downregulation of genes associated with ciliary function and fluid clearance and an increased expression of pro-inflammatory pathways at 7 dpi. These results show that (1) the e-liquid carrier VG/PG increases the pro-inflammatory immune responses to viral pneumonia and that (2) nicotine in an e-cigarette aerosol alters the transcriptomic response to pathogens, blunts host defense mechanisms, increases lung barrier permeability, and reduces viral clearance during influenza infection. In conclusion, acute exposure to aerosolized nicotine can impair clearance of viral infection and exacerbate lung injury, findings that have implications for the regulation of e-cigarette products.

Inhibitory effects of Patchouli alcohol on the early lifecycle stages of influenza A virus

Background

The antiviral activity and underlying mechanism of Patchouli alcohol remain unclear.

Methods

This study evaluated the cytotoxicity, optimal methods for drug administration, anti-influenza A activity of Patchouli alcohol. The antiviral mechanism of Patchouli alcohol was also assessed via qRT-PCR, western blot, hemagglutination inhibiting (HAI) assay, and hemolysis inhibiting assay.

Results

Patchouli alcohol was shown to have low cytotoxicity and its strongest antiviral effect was associated with premixed administration. Patchouli alcohol inhibited virus replication during the early lifecycle stages of influenza A virus infection and specifically prevented expression of the viral proteins, HA and NP. In both the HAI and hemolysis inhibiting assays, Patchouli alcohol was able to block HA2-mediated membrane fusion under low pH conditions. Patchouli alcohol had lower binding energy with HA2 than HA1.

Conclusion

These findings suggest that Patchouli alcohol could be a promising membrane fusion inhibitor for the treatment of influenza A infection.

Fighting cytokine storm and immunomodulatory deficiency: By using natural products therapy up to now

A novel coronavirus strain (COVID-19) caused severe illness and mortality worldwide from 31 December 2019 to 21 March 2023. As of this writing, 761,071,826 million cases have been diagnosed worldwide, with 6,879,677 million deaths accorded by WHO organization and has spread to 228 countries. The number of deaths is closely connected to the growth of innate immune cells in the lungs, mainly macrophages, which generate inflammatory cytokines (especially IL-6 and IL-1β) that induce "cytokine storm syndrome" (CSS), multi-organ failure, and death. We focus on promising natural products and their biologically active chemical constituents as potential phytopharmaceuticals that target virus-induced pro-inflammatory cytokines. Successful therapy for this condition is currently rare, and the introduction of an effective vaccine might take months. Blocking viral entrance and replication and regulating humoral and cellular immunity in the uninfected population are the most often employed treatment approaches for viral infections. Unfortunately, no presently FDA-approved medicine can prevent or reduce SARS-CoV-2 access and reproduction. Until now, the most important element in disease severity has been the host's immune response activation or suppression. Several medicines have been adapted for COVID-19 patients, including arbidol, favipiravir, ribavirin, lopinavir, ritonavir, hydroxychloroquine, chloroquine, dexamethasone, and anti-inflammatory pharmaceutical drugs, such as tocilizumab, glucocorticoids, anakinra (IL-1β cytokine inhibition), and siltuximab (IL-6 cytokine inhibition). However, these synthetic medications and therapies have several side effects, including heart failure, permanent retinal damage in the case of hydroxyl-chloroquine, and liver destruction in the case of remdesivir. This review summarizes four strategies for fighting cytokine storms and immunomodulatory deficiency induced by COVID-19 using natural product therapy as a potential therapeutic measure to control cytokine storms.

Virus Infection and Systemic Inflammation: Lessons Learnt from COVID-19 and Beyond

Respiratory infections with newly emerging zoonotic viruses such as SARS-CoV-2, the etiological agent of COVID-19, often lead to the perturbation of the human innate and adaptive immune responses causing severe disease with high mortality. The responsible mechanisms are commonly virus-specific and often include either over-activated or delayed local interferon responses, which facilitate efficient viral replication in the primary target organ, systemic viral spread, and rapid onset of organ-specific and harmful inflammatory responses. Despite the distinct replication strategies, human infections with SARS-CoV-2 and highly pathogenic avian influenza viruses demonstrate remarkable similarities and differences regarding the mechanisms of immune induction, disease dynamics, as well as the long-term sequelae, which will be discussed in this review. In addition, we will highlight some important lessons about the effectiveness of antiviral and immunomodulatory therapeutic strategies that this pandemic has taught us.

Association between Mesenchymal Stem Cells and COVID-19 Therapy: Systematic Review and Current Trends

Background

The novel coronavirus first emerged in Wuhan, China, and quickly spread across the globe, spanning various countries and resulting in a worldwide pandemic by the end of December 2019. Given the current advances in treatments available for COVID-19, mesenchymal stem cell (MSC) therapy seems to be a prospective option for management of ARDS observed in COVID-19 patients. This present study is aimed at exploring the therapeutic potential and safety of using MSC obtained by isolation from health cord tissues in the treatment of patients with COVID-19.

Methods

A systematic search was done based on the guidelines of the PRISMA 2020 statement. A literature search was executed using controlled vocabulary and indexing of trials to evaluate all the relevant studies involving the use of medical subject headings (MeSH) in electronic databases like PubMed, Embase, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), and clinicaltrials.gov up to 31 December 2021. The protocol was registered in the PROSPERO register with ID CRD42022301666. Findings. After screening finally, 22 remaining articles were included in this systematic review. The studies revealed that MSC exosomes are found to be superior to MSC alone in terms of safety owing to being smaller with a lesser immunological response which leads to free movement in blood capillaries without clumping and also cannot further divide, thus reducing the oncogenic potential of MSC-derived exosomes as compared to MSC only. The studies demonstrated that the lungs healed with the use of exosomes compared to how they presented initially at the hospital. MSCs are found to increase the angiogenesis process and alveolar reepithelization, reducing markers like TNF alpha, TGF beta, and COL I and III, reducing the growth of myofibroblasts and increasing survivability of endothelium leading to attenuated pulmonary fibrosis and even reversing them. Interpretation. We can conclude that the use of mesenchymal stem cells or their derived exosomes is safe and well-tolerated in patients with COVID-19. It improves different parameters of oxygenation and helps in the healing of the lungs. The viral load along with different inflammatory cells and biomarkers of inflammation tend to decrease. Chest X-ray, CT scan, and different radiological tools are used to show improvement and reduced ongoing destructive processes.

Liposomal Dexamethasone Reduces A/H1N1 Influenza-Associated Morbidity in Mice

Re-emerging viral threats have continued to challenge the medical and public health systems. It has become clear that a significant number of severe viral infection cases are due to an overreaction of the immune system, which leads to hyperinflammation. In this study, we aimed to demonstrate the therapeutic efficacy of the dexamethasone nanomedicine in controlling the symptoms of influenza virus infection. We found that the A/Wisconsin/WSLH34939/2009 (H1N1) infection induced severe pneumonia in mice with a death rate of 80%, accompanied by significant epithelial cell damage, infiltration of immune cells, and accumulation of pro-inflammatory cytokines in the airway space. Moreover, the intranasal delivery of liposomal dexamethasone during disease progression reduced the death rate by 20%. It also significantly reduced the protein level of tumor necrosis factor-alpha (TNFα), interleukin-1β (IL-1β), IL-6, and the C-X-C motif chemokine ligand 2 (CXCL2) as well as the number of infiltrated immune cells in the bronchoalveolar lavage fluids as compared to the control and free dexamethasone. The liposomal dexamethasone was mainly distributed into the monocyte/macrophages as a major cell population for inducing the cytokine storm in the lungs. Taken together, the intranasal delivery of liposomal dexamethasone may serve as a novel promising therapeutic strategy for the treatment of influenza A-induced pneumonia.

Role of Dexamethasone and Methylprednisolone Corticosteroids in Coronavirus Disease 2019 Hospitalized Patients: A Review

The WHO announced coronavirus disease 2019 (COVID-19) as a pandemic disease globally on March 11, 2020, after it emerged in China. The emergence of COVID-19 has lasted over a year, and despite promising vaccine reports that have been produced, we still have a long way to go until such remedies are accessible to everyone. The immunomodulatory strategy has been kept at the top priority for the research agenda for COVID-19. Corticosteroids have been used to modulate the immune response in a wide range of diseases for the last 70 years. These drugs have been shown to avoid and reduce inflammation in tissues and the bloodstream through non-genomic and genomic effects. Now, the use of corticosteroids increased the chance of survival and relief by combating the viral strong inflammatory impacts and has moved to the forefront in the management of patients seeking supplemental oxygen. The goal of this review is to illuminate dexamethasone and methylprednisolone, i.e., in terms of their chemical and physical properties, role in COVID-19 patients suffering from pneumonia, the proposed mode of action in COVID-19, pharmacokinetics, pharmacodynamics, clinical outcomes in immunocompromised populations with COVID-19, interaction with other drugs, and contradiction to explore the trends and perspectives for future research. Literature was searched from scientific databases such as Science Direct, Wiley, Springer, PubMed, and books for the preparation of this review. The RECOVERY trial, a massive, multidisciplinary, randomized, and open-label trial, is mainly accountable for recommendations over the usage of corticosteroids in COVID-19 patients. The corticosteroids such as dexamethasone and methylprednisolone in the form of medication have anti-inflammatory, analgesic, and anti-allergic characteristics, including the ability to inhibit the immune system. These drugs are also recommended for treating symptoms of multiple ailments such as rheumatic and autoimmune diseases, leukemia, multiple myeloma, and Hodgkin’s and non-Hodgkin’s lymphoma along with other drugs. Toxicology studies proved them safe usually at low dosage via oral or other routes.

Comparison between methylprednisolone infusion and dexamethasone in COVID-19 ARDS mechanically ventilated patients

Background

Coronavirus disease 2019 (COVID-19) causing severe acute respiratory distress syndrome caused by coronavirus 2 (SARS-CoV-2) still has no solid effective therapy.

From previous studies, dexamethasone has led to a decrease in mortality in patients who required oxygen supplementation mainly invasive mechanical ventilation; at the same time, it is unknown if another corticosteroid can be effective when used and what is the optimal dose and its duration, to achieve improvement in clinical outcome.

The cornerstone of the study was to compare the differences in clinical outcome and laboratory results in intensive care patients with SARS-CoV-2 pneumonia treated with dexamethasone 6 mg/day: doses versus those treated with methylprednisolone 2 mg/kg/day infusion.

Materials and methods

A prospective cohort study with a survival analysis of 414 patients diagnosed with severe COVID-19 pneumonia confirmed by polymerase chain reaction, for SARS-CoV-2 according to the Berlin definition of ARDS, who were admitted in the intensive care unit in the Helwan University Hospitals; the duration is from June 2020 till October 2021.

Patients included in the study were mechanically ventilated with radiological confirmation of pneumonia by chest tomography; patients were included in the study according to the Berlin definition of ARDS and met the inclusion criteria of the study; 222 patients were treated with methylprednisolone infusion with a dose of 2 mg/kg/day versus 192 patients treated with dexamethasone 6 mg/day; both groups were treated for 10 days and were mechanically ventilated; the clinical out come and differences in the laboratory results were evaluated during the 10-day course for each group.

Results

Four hundred fourteen patients had COVID-19 pneumonia, diagnosed and confirmed by ground glass opacities in chest tomography and arterial partial pressure of oxygen/inspired oxygen and fraction of inspired oxygen (P/F ratio) less than 300.

Two hundred twenty-two patients received methylprednisolone infusion at a dose of 2 mg/kg/day, and 192 patients received dexamethasone 6 mg daily; both groups were treated for 10 days.

Inflammatory markers for cytokine storm were improved in the methylprednisolone group in comparison to the patients who were given dexamethasone when comparing the on-admission markers to the results of the inflammatory markers after 10 days, like ferritin after 10 days in methylprednisolone group 292.26 ± 330.10 versus the dexa group 648.10 ± 329.09 (p value < 0.001).

D-dimer in the methylprednisolone group was 1301.75 ± 1515.51 versus 2523.78 ± 843.18 in the dexa group (p value < 0.001); CRP was 49.65 ± 19.91 in the methylprednisolone group versus 100.54 ± 36.75 (p value < 0.001) in the dexa group; LDH after 10 days in methylprednisolone group was 345.09 ± 128.31, and in the dexa group, it was 731.87 ± 195.09 (p value < 0.001); neutrophil to lymphocyte ratio (N:L ratio) after 10 days of treatment in the methylprednisolone group was 17.27 ± 5.09 versus 26.68 ± 7.19 (p value < 0.001) in the dexa group; also, the length of stay was shorter in the methylprednisolone group (7.33 ± 1.71) versus in the dexa group (19.43 ± 5.42) (p value < 0.001), together with mechanical ventilation MV days which are 3.82 ± 1.14 in the methyl group versus 16.57 ± 4.71 in the dexa group (p value < 0.001).

Also, the radiological findings are improved in the methyl group (20.3%) versus the dexa group (73.4%) with p value < 0.001, and discharge from ICU in the methyl group was 79.7% versus 26.6% in the dexa group with p value < 0.001.

Conclusions

Treatment of severe COVID-19 pneumonia, Patients who were mechanically ventilated with methylprednisolone infusion 2 mg/kg/day for 10 days versus dexamethasone 6 mg for 10 days showed a statistically significant improvement in the MV days and length of stay in the intensive care unit, together with the overall mortality and severity inflammatory markers of cytokine storm c-reactive protein (CRP), D-dimer, ferritin, LDH, and N:L ratio.

Early High-Dose Methylprednisolone Therapy Is Associated with Better Outcomes in Children with Acute Necrotizing Encephalopathy

BACKGROUND

The neurologic outcomes of acute necrotizing encephalopathy (ANE) are very poor, with a mortality rate of up to 40% and fewer than 10% of patients surviving without neurologic deficits. Steroid and immunoglobulin treatments have been the most commonly used options for ANE, but their therapeutic efficacy is still controversial.

METHOD

We retrospectively reviewed the medical records of 26 children diagnosed with ANE. We also divided these patients into two groups: 21 patients with brainstem involvement and 8 patients without brainstem involvement. Pulse steroid therapy (methylprednisolone at 30 mg/kg/day for 3 days) and intravenous immunoglobulin (2 g/kg for 2-5 days) were administered to treat ANE.

RESULTS

The overall mortality rate was 42.3%, and patients who did not survive had significantly higher initial lactate and serum ferritin levels, as well as higher rates of inotropic agent use with brainstem involvement. There were no significant differences in the outcomes of pulse steroid therapy or pulse steroid plus immunoglobulin between survivors and non-survivors. When analyzing the time between symptom onset and usage of pulse steroid therapy, pulse steroid therapy used within 24 h after the onset of ANE resulted in significantly better outcomes (p = 0.039). In patients with brainstem involvement, the outcome was not correlated with pulse steroid therapy, early pulse steroid therapy, or pulse steroid therapy combined with immunoglobulin. All patients without brainstem involvement received "early pulse methylprednisolone" therapy, and 87.5% (7/8) of these patients had a good neurologic outcome.

CONCLUSION

Pulse steroid therapy (methylprednisolone at 30 mg/kg/day for 3 days) administered within 24 h after the onset of ANE may be correlated with a good prognosis. Further studies are needed to establish a consensus guideline for this fulminant disease.

Preliminary study regarding the predicted body weight-based dexamethasone therapy in patients with COVID-19 pneumonia

BACKGROUND

The RECOVERY clinical trial reported that 6 mg of dexamethasone once daily for up to 10 days reduces the 28-day mortality in patients with coronavirus disease 2019 (COVID-19) receiving respiratory support. In our clinical setting, a fixed dose of dexamethasone has prompted the question of whether inflammatory modulation effects sufficiently reduce lung injury. Therefore, preliminary verification on the possibility of predicted body weight (PBW)-based dexamethasone therapy was conducted in patients with COVID-19 pneumonia.

METHODS

This single-center retrospective study was conducted in a Japanese University Hospital to compare the treatment strategies/management in different periods. Consecutive patients (n = 90) with COVID-19 pneumonia requiring oxygen therapy and were treated with dexamethasone between June 2020 and May 2021 were analyzed. Initially, 60 patients administered a fixed dexamethasone dose of 6.6 mg/day were defined as the conventional group, and then, 30 patients were changed to PBW-based therapy. The 30-day discharged alive rate and duration of oxygen therapy were analyzed using the Kaplan-Meier method and compared using the log-rank test. The multivariable Cox regression was used to evaluate the effects of PBW-based dexamethasone therapy on high-flow nasal cannula (HFNC), noninvasive ventilation (NIV), or mechanical ventilation (MV).

RESULTS

In the PBW-based group, 9, 13, and 8 patients were administered 6.6, 9.9, and 13.2 mg/day of dexamethasone, respectively. Additional respiratory support including HFNC, NIV, or MV was significantly less frequently used in the PBW-based group (P = 0.0046), with significantly greater cumulative incidence of being discharged alive and shorter oxygen demand within 30 days (92 vs. 89%, log-rank P = 0.0094, 90 vs. 92%, log-rank P = 0.0002, respectively). Patients treated with PBW-based therapy significantly decreased the use of additional respiratory support after adjusting for baseline imbalances (adjusted odds ratio, 0.224; 95% confidence interval, 0.062-0.813, P = 0.023). Infection occurred in 13 (21%) and 2 (7%) patients in the conventional and PBW-based groups, respectively (P = 0.082).

CONCLUSIONS

In patients with COVID-19 pneumonia requiring oxygen therapy, PBW-based dexamethasone therapy may potentially shorten the length of hospital stay and duration of oxygen therapy and risk of using HFNC, NPPV, or MV without increasing serious adverse events or 30-day mortality.

Terretonin as a New Protective Agent against Sepsis-Induced Acute Lung Injury: Impact on SIRT1/Nrf2/NF-κBp65/NLRP3 Signaling

Endophytic fungi are proving to be an excellent source of chemical entities with unique structures and varied bioactivities. Terretonin (TE) and its structurally related derivatives are a class of meroterpenoids, possessing the same unique tetracyclic core skeleton, which have been reported from the Aspergillus genus. This study was carried out to assess the potential protective effects of TE separated from the endophytic fungus A. terreus against LPS (lipopolysaccharide)-induced ALI (acute lung injury) in mice. The results revealed that TE alleviated pulmonary edema as it lowered both the W/D lung ratio and protein content. The inflammatory response represented by inflammatory cell infiltration into the lung tissues was greatly repressed by TE. That was supported by the improved histopathological results and also by the reduced level of myeloperoxidase in the lung. TE showed a potent antioxidant activity as it attenuated lipid peroxidative markers (malondialdehyde, 4-hydroxynonenal, and protein carbonyl) and enhanced endogenous antioxidants (reduced glutathione, superoxide dismutase, and catalase) in lung tissues. Similarly, TE increased the mRNA expression of SIRT1, Nrf2, and its genes (HO-1, NQO1, and GCLm). On the other hand, TE restrained the activation of NF-κB (nuclear factor-κB) in the lung. Consequently, TE depressed the pro-inflammatory cytokines: nitric oxide (NOx), TNF-α (tumor necrosis factor-α), and interleukins (IL-6 and -1β). Additionally, TE inhibited NLRP3 signaling and interrupted apoptosis by decreasing the levels of proapoptotic markers (Bax and caspase-3) and increasing the level of an anti-apoptotic marker (Bcl-2). In conclusion, TE had a remarkable protective potential on LPS-induced lung damage via antioxidant and anti-inflammatory mechanisms. This finding encourages further investigations on this promising candidate.

Current Clinical Application of Mesenchymal Stem Cells in the Treatment of Severe COVID-19 Patients: Review

Coronavirus-2019 disease is a newly diagnosed infectious disease, which is caused by the severe acute respiratory syndrome corona virus-2. It spreads quickly and has become a major public health problem throughout the world. When the viral structural spike protein binds to the angiotensin-converting enzyme-2 receptor of the host cell membrane, the virus enters into host cells. The virus primarily affects lung epithelial cells or other target cells that express angiotensin-converting enzyme-2 receptors in COVID-19 patients. Chemokines released by the host cells stimulate the recruitment of different immune cells. A cytokine storm occurs when a high amount of pro-inflammatory cytokines are produced as a result of the accumulation of immune cells. In COVID-19 patients, cytokine storms are the leading cause of severe acute respiratory distress syndrome. Mesenchymal stem cells are multipotent and self-renewing adult stem cells, which are obtained from a variety of tissues including bone marrow, adipose tissue, Warthon's jelly tissue, and amniotic fluid. Mesenchymal stem cells primarily exert their important therapeutic effects through 2 mechanisms: immunoregulatory effects and differentiation capacity. Mesenchymal stem cells can release several cytokines via paracrine mechanism or by direct interaction with white blood cells such as natural killer cells, T-lymphocytes, B-lymphocytes, natural killer cells, and macrophages, resulting in immune system regulation. Mesenchymal stem cells may help to restore the lung microenvironment, preserve alveolar epithelial cells, prevent lung fibrosis, and treat pulmonary dysfunction that is caused by COVID-19 associated pneumonia. Mesenchymal stem cells therapy may suppress aggressive inflammatory reactions and increase endogenous restoration by improving the pulmonary microenvironment. Furthermore, clinical evidence suggests that intravenous injection of mesenchymal stem cells may radically reduce lung tissue damage in COVID-19 patients. With the advancement of research involving mesenchymal stem cells for the treatment of COVID-19, mesenchymal stem cells therapy may be the main strategy for reducing the recent pandemic.

Specific Cytokine Profiles Predict the Severity of Influenza A Pneumonia: A Prospectively Multicenter Pilot Study

Purpose

Studying the cytokine profiles in influenza A pneumonia could be helpful to better understand the pathogenesis of the disease and predict its prognosis. Patients and Methods. Patients with influenza A pneumonia (including 2009H1N1, H1N1, H3N1, and H7N1) hospitalized in six hospitals from January 2017 to October 2018 were enrolled (ClinicalTrials.gov ID, NCT03093220). Sputum samples were collected within 24 hours after admission and subsequently analyzed for cytokine profiles using a Luminex assay.

Results

A total of 35 patients with influenza A pneumonia were included in the study. The levels of IL-6, IFN-γ, and IL-2 were increased in patients with severe influenza A pneumonia (n =10) (P = 0.002, 0.009, and 0.008, respectively), while those of IL-5, IL-25, IL-17A, and IL-22 were decreased compared to patients with nonsevere pneumonia (P = 0.0001, 0.009, 0.0001, and 0.006, respectively). The levels of IL-2 and IL-6 in the nonsurvivors (n = 5) were significantly higher than those in the survivors (P = 0.043 and 0.0001, respectively), while the levels of IL-5, IL-17A, and IL-22 were significantly lower (P = 0.001, 0.012, and 0.043, respectively). The IL-4/IL-17A ratio has the potential to be a good predictor (AUC = 0.94, P < 0.05, sensitivity = 88.89%, specificity = 92.31%) and an independent risk factor (OR, 95% CI: 3.772, 1.188-11.975; P < 0.05) for intermittent positive pressure ventilation (n = 9).

Conclusion

Significant dysregulation of cytokine profiles can be observed in patients with severe influenza A pneumonia.

Untargeted Metabolic Profiling of Extracellular Vesicles of SARS-CoV-2-Infected Patients Shows Presence of Potent Anti-Inflammatory Metabolites

Extracellular vesicles (EVs) carry important biomolecules, including metabolites, and contribute to the spread and pathogenesis of some viruses. However, to date, limited data are available on EV metabolite content that might play a crucial role during infection with the SARS-CoV-2 virus. Therefore, this study aimed to perform untargeted metabolomics to identify key metabolites and associated pathways that are present in EVs, isolated from the serum of COVID-19 patients. The results showed the presence of antivirals and antibiotics such as Foscarnet, Indinavir, and lymecycline in EVs from patients treated with these drugs. Moreover, increased levels of anti-inflammatory metabolites such as LysoPS, 7-α,25-Dihydroxycholesterol, and 15-d-PGJ2 were detected in EVs from COVID-19 patients when compared with controls. Further, we found decreased levels of metabolites associated with coagulation, such as thromboxane and elaidic acid, in EVs from COVID-19 patients. These findings suggest that EVs not only carry active drug molecules but also anti-inflammatory metabolites, clearly suggesting that exosomes might play a crucial role in negotiating with heightened inflammation during COVID-19 infection. These preliminary results could also pave the way for the identification of novel metabolites that might act as critical regulators of inflammatory pathways during viral infections.

Clinical experience on umbilical cord mesenchymal stem cell treatment in 210 severe and critical COVID-19 cases in Turkey

Objective

Treatment for COVID-19 is still urgent need for the critically ill and severe cases. UC-MSC administration has a therapeutic benefit for severe COVID-19 patients even in the recovery period. In this paper, we aimed to present our clinical experience with UC-MSC treatment in severe and critical severe COVID-19 patients.

Methods

In this study we evaluated the clinical outcome of severe/critically severe 210 COVID-19 patients treated with UC-MSCs, 1–2 × 10⁶ per kilogram to 210 patients from 15/10/2020 until 25/04/2021.

Results

Out of 99 critically severe intubated patients we have observed good clinical progress/discharged from ICU in 52 (52.5%) patients. Where as 86 (77.5%) of 111 severe unintubated patients discharged from ICU. Intubated 47 (47.5%) patients and unintubated 25 (22.5%) patients pass away. Significantly higher survival was observed in patients who underwent UC-MSCs before intubation (OR = 1.475, 95% CI = 1.193–1.824 p < 0.001). It was observed that the SaO₂ parameter tended to improve after UC-MSC therapy compared to all groups. But SaO₂ parameter between intubated and unintubated groups was not statistically significant (p > 0.05), while in discharged cases SaO₂ parameter was statistically significant (p = 0.01). Besides, there was a statistically significant relation with intubation status, age (OR = 3.868, 95% CI = 0.574–7.152 p = 0.02) and weigh (OR = 6.768, 95% CI = 3.423–10.112 p < 0.001) thus presented an elevated risk for COVID-19. The linear regression analysis confirmed that the high weight was associated with the risk of intubation in COVID-19 (p = 0.001).

Conclusions

According to our results and from recent studies, UC-MSC treatment is safe with high potential to be used as an added therapeutic treatment for severe COVID-19 patients. Our experience showed that UC-MSC therapy may restore oxygenation and downregulate cytokine storm in patients hospitalized with severe COVID-19. We advice wider randomised studies to discover the detailed therapeutic pathophysiology of the MSCs on COVID-19 patients.

Graphical abstract

MSCs transplantation improves the damaging effects of the cytokine storm through immunomodulation and improving tissue and organ repair. Severe patients who were unintubated were in the Phase I, while critical patients who were intubated were in the Phase II. The figure is created via biorender application, (BioRender.com).

Characteristics and Developments in Mesenchymal Stem Cell Therapy for COVID-19: An Update

The outbreak of coronavirus disease 2019 (COVID-19) has so far resulted in over a hundred million people being infected. COVID-19 poses a threat to human health around the world. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been confirmed as the pathogenic virus of COVID-19. SARS-CoV-2 belongs to the β-coronavirus family of viruses and is mainly transmitted through the respiratory tract. It has been proven that SARS-CoV-2 mainly targets angiotensin-converting enzyme II (ACE2) receptors on the surface of various cells in humans. The main clinical symptoms of COVID-19 include fever, cough, and severe acute respiratory distress syndrome (ARDS). Current evidence suggests that the damage caused by the virus may be closely related to the induction of cytokine storms in COVID-19. No specific drugs or measures have yet to be shown to cure COVID-19 completely. Cell-based approaches, primarily mesenchymal stem cells (MSCs), have been identified to have anti-inflammatory and immune functions in COVID-19. Clinical studies about using MSCs and its derivatives-exosomes for COVID-19 treatment-are under investigation. Here, we review the current progress of the biological characteristics, clinical manifestations, and cell-based treatment development for COVID-19. Providing up-to-date information on COVID-19 and potential MSC therapies will help highlight routes to prevent and treat the disease.

Plasma exchange therapy for acute necrotizing encephalopathy of childhood

IMPORTANCE

Acute necrotizing encephalopathy (ANE) is a rare disease with high mortality. Plasma exchange (PLEX) has recently been reported to treat ANE of childhood (ANEC), but its efficacy is uncertain.

OBJECTIVE

This study aimed to investigate the effectiveness of PLEX on ANEC.

METHODS

A retrospective study was conducted in four pediatric intensive care units from December 2014 to December 2020. All patients who were diagnosed with ANEC were included; however, these patients were excluded if their length of stay was less than 24 h. Participants were classified into PLEX and non-PLEX groups.

RESULTS

Twenty-nine patients with ANEC were identified, 10 in the PLEX group and 19 in the non-PLEX group. In the PLEX group, C-reactive protein, procalcitonin, alanine aminotransferase, and aspartate aminotransaminase levels were significantly lower after 3 days of treatment than before treatment (13.1 vs. 8.0, P = 0.043; 9.8 vs. 1.5, P = 0.028; 133.4 vs. 31.9, P = 0.028; 282.4 vs. 50.5, P = 0.046, respectively). Nine patients (31.0%, 9/29) died at discharge, and a significantly difference was found between the PLEX group and non-PLEX group [0 vs. 47.4% (9/19), P = 0.011]. The median follow-up period was 27 months, and three patients were lost to follow-up. Thirteen patients (50.0%, 13/26) died at the last follow-up, comprising three (33.3%, 3/9) in the PLEX group and ten (58.8%, 10/17) in the non-PLEX group, but there was no significant difference between the two groups (P = 0.411). Three patients (10.3%, 3/29) fully recovered.

INTERPRETATION

PLEX may reduce serum C-reactive protein and procalcitonin levels and improve liver function in the short term. PLEX may improve the prognosis of ANEC, and further studies are needed.

Medicinal Plants and Isolated Molecules Demonstrating Immunomodulation Activity as Potential Alternative Therapies for Viral Diseases Including COVID-19

Plants have been extensively studied since ancient times and numerous important chemical constituents with tremendous therapeutic potential are identified. Attacks of microorganisms including viruses and bacteria can be counteracted with an efficient immune system and therefore, stimulation of body’s defense mechanism against infections has been proven to be an effective approach. Polysaccharides, terpenoids, flavonoids, alkaloids, glycosides, and lactones are the important phytochemicals, reported to be primarily responsible for immunomodulation activity of the plants. These phytochemicals may act as lead molecules for the development of safe and effective immunomodulators as potential remedies for the prevention and cure of viral diseases. Natural products are known to primarily modulate the immune system in nonspecific ways. A number of plant-based principles have been identified and isolated with potential immunomodulation activity which justify their use in traditional folklore medicine and can form the basis of further specified research. The aim of the current review is to describe and highlight the immunomodulation potential of certain plants along with their bioactive chemical constituents. Relevant literatures of recent years were searched from commonly employed scientific databases on the basis of their ethnopharmacological use. Most of the plants displaying considerable immunomodulation activity are summarized along with their possible mechanisms. These discussions shall hopefully elicit the attention of researchers and encourage further studies on these plant-based immunomodulation products as potential therapy for the management of infectious diseases, including viral ones such as COVID-19.

Interplay of Opposing Effects of the WNT/β-Catenin Pathway and PPARγ and Implications for SARS-CoV2 Treatment

The Coronavirus disease 2019 (COVID-19), caused by the novel coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), has quickly reached pandemic proportions. Cytokine profiles observed in COVID-19 patients have revealed increased levels of IL-1β, IL-2, IL-6, and TNF-α and increased NF-κB pathway activity. Recent evidence has shown that the upregulation of the WNT/β-catenin pathway is associated with inflammation, resulting in a cytokine storm in ARDS (acute respire distress syndrome) and especially in COVID-19 patients. Several studies have shown that the WNT/β-catenin pathway interacts with PPARγ in an opposing interplay in numerous diseases. Furthermore, recent studies have highlighted the interesting role of PPARγ agonists as modulators of inflammatory and immunomodulatory drugs through the targeting of the cytokine storm in COVID-19 patients. SARS-CoV2 infection presents a decrease in the angiotensin-converting enzyme 2 (ACE2) associated with the upregulation of the WNT/β-catenin pathway. SARS-Cov2 may invade human organs besides the lungs through the expression of ACE2. Evidence has highlighted the fact that PPARγ agonists can increase ACE2 expression, suggesting a possible role for PPARγ agonists in the treatment of COVID-19. This review therefore focuses on the opposing interplay between the canonical WNT/β-catenin pathway and PPARγ in SARS-CoV2 infection and the potential beneficial role of PPARγ agonists in this context.

Methylprednisolone or dexamethasone, which one is superior corticosteroid in the treatment of hospitalized COVID-19 patients: a triple-blinded randomized controlled trial

BACKGROUND

Although almost a year has passed since the Coronavirus disease 2019 (COVID-19) outbreak and promising reports of vaccines have been presented, we still have a long way until these measures are available for all. Furthermore, the most appropriate corticosteroid and dose in the treatment of COVID-19 have remained uncertain. We conducted a study to assess the effectiveness of methylprednisolone treatment versus dexamethasone for hospitalized COVID-19 patients.

METHODS

In this prospective triple-blinded randomized controlled trial, we enrolled 86 hospitalized COVID-19 patients from August to November 2020, in Shiraz, Iran. The patients were randomly allocated into two groups to receive either methylprednisolone (2 mg/kg/day; intervention group) or dexamethasone (6 mg/day; control group). Data were assessed based on a 9-point WHO ordinal scale extending from uninfected (point 0) to death (point 8).

RESULTS

There were no significant differences between the groups on admission. However, the intervention group demonstrated significantly better clinical status compared to the control group at day 5 (4.02 vs. 5.21, p = 0.002) and day 10 (2.90 vs. 4.71, p = 0.001) of admission. There was also a significant difference in the overall mean score between the intervention group and the control group, (3.909 vs. 4.873 respectively, p = 0.004). The mean length of hospital stay was 7.43 ± 3.64 and 10.52 ± 5.47 days in the intervention and control groups, respectively (p = 0.015). The need for a ventilator was significantly lower in the intervention group than in the control group (18.2% vs 38.1% p = 0.040).

CONCLUSION

In hospitalized hypoxic COVID-19 patients, methylprednisolone demonstrated better results compared to dexamethasone.

TRIAL REGISTRATION

The trial was registered with IRCT.IR (08/04/2020-No. IRCT20200204046369N1 ).

iPSC screening for drug repurposing identifies anti-RNA virus agents modulating host cell susceptibility

Human pathogenic RNA viruses are threats to public health because they are prone to escaping the human immune system through mutations of genomic RNA, thereby causing local outbreaks and global pandemics of emerging or re-emerging viral diseases. While specific therapeutics and vaccines are being developed, a broad-spectrum therapeutic agent for RNA viruses would be beneficial for targeting newly emerging and mutated RNA viruses. In this study, we conducted a screen of repurposed drugs using Sendai virus (an RNA virus of the family Paramyxoviridae), with human-induced pluripotent stem cells (iPSCs) to explore existing drugs that may present anti-RNA viral activity. Selected hit compounds were evaluated for their efficacy against two important human pathogens: Ebola virus (EBOV) using Huh7 cells and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using Vero E6 cells. Selective estrogen receptor modulators (SERMs), including raloxifene, exhibited antiviral activities against EBOV and SARS-CoV-2. Pioglitazone, a PPARγ agonist, also exhibited antiviral activities against SARS-CoV-2, and both raloxifene and pioglitazone presented a synergistic antiviral effect. Finally, we demonstrated that SERMs blocked entry steps of SARS-CoV-2 into host cells. These findings suggest that the identified FDA-approved drugs can modulate host cell susceptibility against RNA viruses.

Stem Cells Therapy as a Possible Therapeutic Option in Treating COVID-19 Patients

An unfortunate emergence of a new virus SARS-CoV-2, causing a disease known as COVID-19, has spread all around the globe and has caused a pandemic. It primarily affects the respiratory tract and lungs in some cases causing severe organ damage and pneumonia due to overwhelming immune responses. Clinical reports show that the most commons symptoms are fever, dry cough, and shortness of breath, along with several other symptoms. It is thought that an immense cytokine dysregulation in COVID-19 patients is caused following the virus infection. Notably, if patients present with pre-existing specific comorbidities like diabetes or high blood pressure, rates of COVID-19 induced complications and deaths are escalated. Mesenchymal stem cell (MSC) therapy has been shown to alleviate pneumonia and acute respiratory syndrome (ARDS) symptoms, through their immunomodulatory activities in COVID-19 patients. Although more research studies and clinical trial results are needed to elucidate the exact mechanism by which MSCs provide relief to COVID-19 infected patients. Results from clinical trials are encouraging as patients treated with MSCs, regain lung functions and have restored levels of cytokines and trophic factors underscoring the fact that stem cell therapy can be, at least, a complementary therapy to alleviate sufferings in COVID-19 patients. This review discusses the possible therapeutic uses of MSCs for treating COVID-19. Graphical Abstract.

Antiviral Activity of 3D, a Butene Lactone Derivative Against Influenza A Virus In Vitro and In Vivo

Influenza A virus is a highly variable and contagious respiratory pathogen that can cause annual epidemics and it poses an enormous threat to public health. Therefore, there is an urgent need for a new generation of antiviral drugs to combat the emergence of drug-resistant strains of the influenza virus. A novel series of butene lactone derivatives were screened and the compound 3D was selected, as it exhibited in vitro potential antiviral activity against A/Weiss/43 H1N1 virus with low toxicity. In addition, 3D dose-dependently inhibited the viral replication, expression of viral mRNA and viral proteins. 3D exerted a suppressive effect on A/Virginia/ATCC2/2009 H1N1 and A/California/2/2014 H3N2 in vitro. The time-of-addition analysis indicated that 3D suppressed H1N1 in the early stage of its life cycle. A/Weiss/43 H1N1-induced apoptosis in A549 cells was reduced by 3D via the mitochondrial apoptosis pathway. 3D could decrease the production of H1N1-induced pro-inflammatory cytokines that are induced by H1N1 in vitro and in vivo. The administration of 3D reduced lung lesions and virus load in vivo. These results suggest that 3D, which is a butene lactone derivative, is a promising agent for the treatment of influenza A virus infection.

PPAR Gamma: From Definition to Molecular Targets and Therapy of Lung Diseases

Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear receptor superfamily that regulate the expression of genes related to lipid and glucose metabolism and inflammation. There are three members: PPARα, PPARβ or PPARγ. PPARγ have several ligands. The natural agonists are omega 9, curcumin, eicosanoids and others. Among the synthetic ligands, we highlight the thiazolidinediones, clinically used as an antidiabetic. Many of these studies involve natural or synthetic products in different pathologies. The mechanisms that regulate PPARγ involve post-translational modifications, such as phosphorylation, sumoylation and ubiquitination, among others. It is known that anti-inflammatory mechanisms involve the inhibition of other transcription factors, such as nuclear factor kB(NFκB), signal transducer and activator of transcription (STAT) or activator protein 1 (AP-1), or intracellular signaling proteins such as mitogen-activated protein (MAP) kinases. PPARγ transrepresses other transcription factors and consequently inhibits gene expression of inflammatory mediators, known as biomarkers for morbidity and mortality, leading to control of the exacerbated inflammation that occurs, for instance, in lung injury/acute respiratory distress. Many studies have shown the therapeutic potentials of PPARγ on pulmonary diseases. Herein, we describe activities of the PPARγ as a modulator of inflammation, focusing on lung injury and including definition and mechanisms of regulation, biological effects and molecular targets, and its role in lung diseases caused by inflammatory stimuli, bacteria and virus, and molecular-based therapy.

Effect of methylprednisolone in severe and critical COVID-19: Analysis of 102 cases

BACKGROUND

The coronavirus disease 2019 (COVID-19) outbreak has brought great challenges to public health. Aggravation of COVID-19 is closely related to the secondary systemic inflammatory response. Glucocorticoids are used to control severe diseases caused by the cytokine storm, owing to their anti-inflammatory effects. However, glucocorticoids are a double-edged sword, as the use of large doses has the potential risk of secondary infection and long-term serious complications, and may prolong virus clearance time. Nonetheless, the risks and benefits of glucocorticoid adjuvant therapy for COVID-19 are inconclusive.

AIM

To determine the effect of methylprednisolone in severe and critically ill patients with COVID-19.

METHODS

This single-center retrospective study included 102 adult COVID-19 patients admitted to a ward of a designated hospital in Wuhan, Hubei Province from January to March 2020. All patients received general symptomatic treatment and organ function support, and were given different respiratory support measures according to their conditions. In case of deterioration, considering the hyperinflammatory state of the patients, methylprednisolone was intravenously administered at 0.75-1.5 mg/kg/d, usually for less than 14 d. Patient vital signs and oxygenation were closely monitored, in combination with imaging and routine blood tests such as C-reactive protein, biochemical indicators (liver and kidney function, myocardial enzymes, electrolytes, etc.), and coagulation function. Patient clinical outcomes were discharge or death.

RESULTS

A total of 102 severe and critically ill COVID-19 patients were included in this study. They were divided into treatment (69, 67.6%) and control groups (33, 32.4%) according to methylprednisolone use. Comparison of baseline data between the two groups showed that the treatment group patients had higher aspartic acid aminotransferase, globulin, hydroxybutyrate dehydrogenase, and lactate dehydrogenase. There was no significant difference in other baseline data between the two groups. With regard to prognosis, 29 (78.4%) patients in the treatment group died as opposed to 40 (61.5%) in the control group. The mortality was higher in the treatment group than in the control group; however, according to the log-rank test and the Kaplan-Meier survival curve, the difference in mortality between both groups was insignificant (P = 0.655). The COX regression equation was used to correct the variables with differences, and the results showed that methylprednisolone treatment did not improve prognosis.

CONCLUSION

Methylprednisolone treatment does not improve prognosis in severe and critical COVID-19 patients.

Innate immune responses in RNA viral infection

RNA viruses cause a multitude of human diseases, including several pandemic events in the past century. Upon viral invasion, the innate immune system responds rapidly and plays a key role in activating the adaptive immune system. In the innate immune system, the interactions between pathogen-associated molecular patterns and host pattern recognition receptors activate multiple signaling pathways in immune cells and induce the production of pro-inflammatory cytokines and interferons to elicit antiviral responses. Macrophages, dendritic cells, and natural killer cells are the principal innate immune components that exert antiviral activities. In this review, the current understanding of innate immunity contributing to the restriction of RNA viral infections was briefly summarized. Besides the main role of immune cells in combating viral infection, the intercellular transfer of pathogen and host-derived materials and their epigenetic and metabolic interactions associated with innate immunity was discussed. This knowledge provides an enhanced understanding of the innate immune response to RNA viral infections in general and aids in the preparation for the existing and next emerging viral infections.

"Cytokine storm", not only in COVID-19 patients. Mini-review

Cytokine storm is a form of uncontrolled systemic inflammatory reaction activated by a variety of factors and leading to a harmful homeostatic process, even to patient's death. Triggers that start the reaction are infection, systemic diseases and rarely anaphylaxis. Cytokine storm is frequently mentioned in connection to medical interventions such as transplantation or administration of drugs. Presented mini-review would like to show current possibilities how to fight or even stop such a life-threatening, immune-mediated process in order to save lives, not only in COVID-19 patients. Early identification of rising state and multilevel course of treatment is imperative. The most widely used molecule for systemic treatment remains tocilizumab. Except for anti IL-6 treatment, contemporary research opens the possibilities for combination of pharmaceutical, non-pharmaceutical and adjunctive treatment in a successful fight with consequences of cytokine storm. Further work is needed to discover the exact signaling pathways that lead to cytokine storm and to determine how these effector molecules and/or combination of processes can help to resolve this frequently fatal episode of inflammation. It is a huge need for all scientists and clinicians to establish a physiological rational for new therapeutic targets that might lead to more personalized medicine approaches.

Controlling Cytokine Storm Is Vital in COVID-19

Corona virus disease 2019 (COVID-19) has caused a global outbreak and severely posed threat to people's health and social stability. Mounting evidence suggests that immunopathological changes, including diminished lymphocytes and elevated cytokines, are important drivers of disease progression and death in coronavirus infections. Cytokine storm not only limits further spread of virus in the body but also induces secondary tissue damage through the secretion of large amounts of active mediators and inflammatory factors. It has been determined that cytokine storm is a major cause of deaths in COVID-19; therefore, in order to reverse the deterioration of severe and critically ill patients from this disease, the cytokine storm has become a key therapeutic target. Although specific mechanisms of the occurrences of cytokine storms in COVID-19 have not been fully illuminated, hyper-activated innate immune responses, and dysregulation of ACE2 (angiotensin converting enzyme 2) expression and its downstream pathways might provide possibilities. Tailored immunoregulatory therapies have been applied to counteract cytokine storms, such as inhibition of cytokines, corticosteroids, blood purification therapy, and mesenchymal stem cell therapy. This review will summarize advances in the research of cytokine storms induced by COVID-19, as well as potential intervention strategies to control cytokine storms.

SARS-CoV-2 Infection Boosts MX1 Antiviral Effector in COVID-19 Patients

In a published case-control study (GSE152075) from SARS-CoV-2-positive (n = 403) and -negative patients (n = 50), we analyzed the response to infection assessing gene expression of host cell receptors and antiviral proteins. The expression analysis associated with reported risk factors for COVID-19 was also assessed. SARS-CoV-2 cases had higher ACE2, but lower TMPRSS2, BSG/CD147, and CTSB expression compared with negative cases. COVID-19 patients' age negatively affected ACE2 expression. MX1 and MX2 were higher in COVID-19 patients. A negative trend for MX1 and MX2 was observed as patients' age increased. Principal-component analysis determined that ACE2, MX1, MX2, and BSG/CD147 expression was able to cluster non-COVID-19 and COVID-19 individuals. Multivariable regression showed that MX1 expression significantly increased for each unit of viral load increment. Altogether, these findings support differences in ACE2, MX1, MX2, and BSG/CD147 expression between COVID-19 and non-COVID-19 patients and point out to MX1 as a critical responder in SARS-CoV-2 infection.

Human Umbilical Cord Mesenchymal Stem Cells for Adjuvant Treatment of a Critically Ill COVID-19 Patient: A Case Report

Background

COVID-19 (coronavirus disease 2019) has become a global public health emergency since patients were first detected in Wuhan, China, in December 2019. Currently, there are no satisfying antiviral medications and vaccines available.

Case Presentation

We reported the treatment process and clinical outcome of a 48-year-old man critically ill COVID-19 patient who received transfusion of allogenic human umbilical cord mesenchymal stem cells (UC-MSCs).

Conclusions

We proposed that UC-MSC transfusion might be a new option for critically ill COVID-19. Although only one case we were shown, more similar clinical cases are inquired for further evidence providing the potential effectiveness of UC-MSC treatment.

Efficacy of clarithromycin-naproxen-oseltamivir combination therapy versus oseltamivir alone in hospitalized pediatric influenza patients

PURPOSE

This study aimed to compare the safety and efficacy of clarithromycin-naproxen-oseltamivir combination therapy to that of oseltamivir therapy alone in hospitalized pediatric influenza patients.

METHODS

This prospective, single-blind study included children aged 1-18 years hospitalized with influenza, in MacKay Children's Hospital, Taiwan, between December 2017 and December 2019. The primary outcomes were the time to defervescence and decrease of the Pediatric Respiratory Severity Score (PRESS) during hospitalization. The secondary outcomes were serial changes in virus titers, measured using real-time polymerase chain reaction.

RESULTS

Fifty-four patients were enrolled (28 in the control group and 26 in the combination group) in total. There were no differences in the patients' baseline characteristics between the groups. The time to defervescence was significantly shorter in the combination group than the oseltamivir group (13.2 h vs. 32.1 h, p = 0.002). The decrease in the virus titer from days 1-3 (log Δ13) was more pronounced in the combination group than the oseltamivir group. (39% vs. 19%, p = 0.001). There were no differences in adverse effects such as vomiting, diarrhea, and abdominal pain during the study or within 30 days after antiviral therapy.

CONCLUSION

The clarithromycin-naproxen-oseltamivir combination group experienced a more rapid defervescence and a more rapid decline of influenza virus titer than the group treated with oseltamivir alone. Further consideration should be given to whether the overall benefits of combination therapy in hospitalized pediatric influenza patients outweigh the risks.

Targeting the Linear Ubiquitin Assembly Complex to Modulate the Host Response and Improve Influenza A Virus Induced Lung Injury

Influenza virus infection is characterized by symptoms ranging from mild congestion and body aches to severe pulmonary edema and respiratory failure. While the majority of those exposed have minor symptoms and recover with little morbidity, an estimated 500,000 people succumb to IAV-related complications each year worldwide. In these severe cases, an exaggerated inflammatory response, known as "cytokine storm", occurs which results in damage to the respiratory epithelial barrier and development of acute respiratory distress syndrome (ARDS). Data from retrospective human studies as well as experimental animal models of influenza virus infection highlight the fine line between an excessive and an inadequate immune response, where the host response must balance viral clearance with exuberant inflammation. Current pharmacological modulators of inflammation, including corticosteroids and statins, have not been successful in improving outcomes during influenza virus infection. We have reported that the amplitude of the inflammatory response is regulated by Linear Ubiquitin Assembly Complex (LUBAC) activity and that dampening of LUBAC activity is protective during severe influenza virus infection. Therapeutic modulation of LUBAC activity may be crucial to improve outcomes during severe influenza virus infection, as it functions as a molecular rheostat of the host response. Here we review the evidence for modulating inflammation to ameliorate influenza virus infection-induced lung injury, data on current anti-inflammatory strategies, and potential new avenues to target viral inflammation and improve outcomes.

Clinical remission of a critically ill COVID-19 patient treated by human umbilical cord mesenchymal stem cells: A case report

RATIONALE

The COVID-19 cases increased very fast in January and February 2020. The mortality among critically ill patients, especially the elder ones, is relatively high. Considering many patients died of severe inflammation response, it is urgent to develop effective therapeutic strategies for these patients. The human umbilical cord mesenchymal stem cells (hUCMSCs) have shown good capabilities to modulate the immune response and repair the injured tissue. Therefore, investigating the potential of hUCMSCs to the treatment of COVID-19 critically ill patients is necessary.

PATIENT CONCERNS

A 65-year-old woman felt fatigued and had a fever with body temperature of 38.2C, coughed up white foaming sputum. After 1 day, she had chest tightness with SPO2 of 81%, and blood pressure of 160/91 mm Hg.

DIAGNOSE

According to the guideline for the diagnosis and treatment of 2019 novel coronavirus infected pneumonia (Trial 4th Edition), COVID-19 was diagnosed, based on the real-time RT-PCR test of SARS-CoV-2.

INTERVENTIONS

After regular treatment for 12 days, the inflammation symptom of the patient was still very severe and the potential side effects of corticosteroid were observed. Then, allogenic hUCMSCs were given 3 times (5 × 10 cells each time) with a 3-day interval, together with thymosin α1 and antibiotics daily injection.

OUTCOMES

After these treatments, most of the laboratory indexes and CT images showed remission of the inflammation symptom. The patient was subsequently transferred out of ICU, and the throat swabs test reported negative 4 days later.

LESSONS

These results indicated the clinical outcome and good tolerance of allogenic hUCMSCs transfer.

Influenza and obesity: its odd relationship and the lessons for COVID-19 pandemic

AIMS

Analyze the relationship between obesity and influenza.

METHODS

Basal hormone milieu, defective response of both innate and adaptive immune system and sedentariness are major determinants in the severity of influenza viral infection in obese patients. Being overweight not only increases the risk of infection and of complications for the single obese person, but a large prevalence of obese individuals within the population might increase the chance of appearance of more virulent viral strain, prolongs the virus shedding throughout the total population and eventually might increase overall mortality rate of an influenza pandemic.

RESULTS

Waiting for the development of a vaccination against COVID-19, isolation of positive cases and social distancing are the primary interventions. Nonetheless, evidence from previous influenza pandemics suggests the following interventions aimed at improving immune response: (1) lose weight with a mild caloric restriction; (2) include AMPK activators and PPAR gamma activators in the drug treatment for obesity associated with diabetes; and (3) practice mild-to-moderate physical exercise.

CONCLUSIONS

Due to prolonged viral shedding, quarantine in obese subjects should likely be longer than normal weight individuals.

Ethanol Extract of Caesalpinia decapetala Inhibits Influenza Virus Infection In Vitro and In Vivo

Influenza virus infections can lead to viral pneumonia and acute respiratory distress syndrome in severe cases, causing significant morbidity and mortality and posing a great threat to human health. Because of the diversity of influenza virus strains and drug resistance to the current direct antiviral agents, there have been no effective drugs as yet to cure all patients infected by influenza viruses. Natural products from plants contain compounds with diverse structures that have the potential to interact with multiple host and virus factors. In this study, we identified the ethanol extract of Caesalpinia decapetala (Roth) Alston (EEC) as an inhibitor against the replication of a panel of influenza A and B viruses both on human pulmonary epithelial A549 and human monocytic U937 cells. The animal study revealed that EEC administration reduces the weight loss and improves the survival rate of mice infected with lethal influenza virus. Also, EEC treatment attenuated lung injury and reduced virus titer significantly. In conclusion, we showed that EEC has antiviral activity both in vitro and in vivo, suggesting that the plant C. decapetala has the potential to be further developed as a resource of new anti-influenza drugs.

Targeting the Linear Ubiquitin Assembly Complex to Modulate the Host Response and Improve Influenza A Virus Induced Lung Injury

Influenza virus infection is characterized by symptoms ranging from mild congestion and body aches to severe pulmonary edema and respiratory failure. While the majority of those exposed have minor symptoms and recover with little morbidity, an estimated 500,000 people succumb to IAV-related complications each year worldwide. In these severe cases, an exaggerated inflammatory response, known as "cytokine storm", occurs which results in damage to the respiratory epithelial barrier and development of acute respiratory distress syndrome (ARDS). Data from retrospective human studies as well as experimental animal models of influenza virus infection highlight the fine line between an excessive and an inadequate immune response, where the host response must balance viral clearance with exuberant inflammation. Current pharmacological modulators of inflammation, including corticosteroids and statins, have not been successful in improving outcomes during influenza virus infection. We have reported that the amplitude of the inflammatory response is regulated by Linear Ubiquitin Assembly Complex (LUBAC) activity and that dampening of LUBAC activity is protective during severe influenza virus infection. Therapeutic modulation of LUBAC activity may be crucial to improve outcomes during severe influenza virus infection, as it functions as a molecular rheostat of the host response. Here we review the evidence for modulating inflammation to ameliorate influenza virus infection-induced lung injury, data on current anti-inflammatory strategies, and potential new avenues to target viral inflammation and improve outcomes.

Pharmacological (or Synthetic) and Nutritional Agonists of PPAR-γ as Candidates for Cytokine Storm Modulation in COVID-19 Disease

The cytokine storm is an abnormal production of inflammatory cytokines, due to the over-activation of the innate immune response. This mechanism has been recognized as a critical mediator of influenza-induced lung disease, and it could be pivotal for COVID-19 infections. Thus, an immunomodulatory approach targeting the over-production of cytokines could be proposed for viral aggressive pulmonary disease treatment. In this regard, the peroxisome proliferator-activated receptor (PPAR)-γ, a member of the PPAR transcription factor family, could represent a potential target. Beside the well-known regulatory role on lipid and glucose metabolism, PPAR-γ also represses the inflammatory process. Similarly, the PPAR-γ agonist thiazolidinediones (TZDs), like pioglitazone, are anti-inflammatory drugs with ameliorating effects on severe viral pneumonia. In addition to the pharmacological agonists, also nutritional ligands of PPAR-γ, like curcuma, lemongrass, and pomegranate, possess anti-inflammatory properties through PPAR-γ activation. Here, we review the main synthetic and nutritional PPAR-γ ligands, proposing a dual approach based on the strengthening of the immune system using pharmacological and dietary strategies as an attempt to prevent/treat cytokine storm in the case of coronavirus infection.

Metabolic Perturbations and Severe COVID-19 Disease: Implication of Molecular Pathways

Coronavirus disease (COVID-19) is caused by SARS-CoV-2 virus, which can result in serious respiratory illnesses such as pneumonia leading to respiratory failure. It was first reported in Wuhan, Hubei, China, in December 2019 and rapidly spread globally, becoming a pandemic in March 2020. Among comorbidities observed in SARS-CoV-2 positive patients, hypertension (68.3%) and type 2-diabetes (30.1%) are the most frequent conditions. Although symptoms are highly heterogeneous (ranging from absence of symptoms to severe acute respiratory failure), patients with metabolic-associated diseases often experience worse COVID-19 outcomes. This review investigates the association between metabolic disorders and COVID-19 severity, exploring the molecular mechanisms potentially underlying this relationship and those that are responsible for more severe COVID-19 outcomes. In addition, the role of the main biological processes that may connect metabolic alterations to SARS-CoV-2 infection such as hyperglycemia, immune system deregulation, ACE-2 receptor modulation, and inflammatory response is described. The impact of metabolic disorders on the prognosis of COVID-19 has major implications in public health especially for countries affected by a high incidence of metabolic diseases.

The healthy Nordic diet for blood glucose control: a systematic review and meta-analysis of randomized controlled clinical trials

AIMS

Investigations on the possible effect of the Nordic diet (ND) on the glycemic control and the risk of diabetes have led to inconsistent results. The present study tried to determine the effect of the ND on the markers of blood glucose control using a systematic review and meta-analysis of randomized controlled clinical trials (RCTs).

METHODS

Predefined keywords were used to search PubMed, ISI Web of Science, Scopus and Google Scholar up to April 2019. The random effects model was used to compute the overall estimates.

RESULTS

In total, six RCTs with 618 participants (6-26 weeks of follow-up period) were included in the present study. The meta-analysis revealed that the ND might not have a considerable effect on fasting blood glucose levels [weighted mean difference (WMD) = -0.05 mmol/l, 95% CI - 0.13, 0.01, P = 0.112]. In contrast, the analyses showed that the ND significantly reduces serum insulin concentrations (WMD = -1.12 mU/l, 95% CI - 1.84, - 0.39, P = 0.002) and the homeostasis model assessment for insulin resistance (HOMA-IR) (WMD = - 0.34, 95% CI - 0.53, - 0.14, P = 0.001) compared to control diets. The effect on serum insulin levels was sensitive to one of the included studies. This dietary pattern did not significantly affect 2-h post-prandial blood glucose and Matsuda index.

CONCLUSIONS

Adherence to the ND might improve serum insulin and HOMA-IR levels; however, this effect was not confirmed for other markers of blood glucose control. Future well-designed and long-term clinical trials are highly recommended.

Targeting Peroxisome Proliferator-Activated Receptor-Gamma Decreases Host Mortality After Influenza Infection in Obese Mice

Obesity is an independent risk factor for severe influenza infection. However, the underlying cellular and molecular mechanisms are still incompletely understood. In this study, we have utilized a murine influenza infection model in genetic-induced obese (db/db) mice to explore the mechanisms by which obesity increases host susceptibility to influenza infection. We find that db/db mice have enhanced viral replication, exaggerated inflammatory responses, and dysregulated lung repair process after influenza infection, and consequently increased host mortality. Furthermore, we demonstrate that the transcription factor peroxisome proliferator-activated receptor-gamma (PPAR-γ), an important inflammation regulator, was downregulated in the lung macrophages of db/db mice after influenza infection. Strikingly, the treatment of 15-deoxy-Δ12, 14-prostaglandin J2 (15d-PGJ2), a PPAR-γ agonist, largely rescued the survival of db/db mice after influenza infection. Interestingly, macrophage PPAR-γ-deficient mice exhibited enhanced mortality after influenza infection and 15d-PGJ2 fails to rescue host mortality in macrophage PPAR-γ-deficient mice, suggesting that PPAR-γ expression in macrophages is critical for the action of 15d-PGJ2. These data indicate that obesity attenuates lung antiviral immunity and hampers host recovery through the modulation of macrophage PPAR-γ expression. Furthermore, modalities targeting macrophage PPAR-γ expression and/or function may serve as promising therapeutics to treat severe influenza infection in obese patients.