Meta-analysis of high doses of ambroxol treatment for acute lung injury/acute respiratory distress syndrome based on randomized controlled trials

Effects of pulmonary surfactant combined with noninvasive positive pressure ventilation in neonates with respiratory distress syndrome

BACKGROUND

Neonatal respiratory distress syndrome (NRDS) is one of the most common diseases in neonatal intensive care units, with an incidence rate of about 7% among infants. Additionally, it is a leading cause of neonatal death in hospitals in China. The main mechanism of the disease is hypoxemia and hypercapnia caused by lack of surfactant

AIM

To explore the effect of pulmonary surfactant (PS) combined with noninvasive positive pressure ventilation on keratin-14 (KRT-14) and endothelin-1 (ET-1) levels in peripheral blood and the effectiveness in treating NRDS.

METHODS

Altogether 137 neonates with respiratory distress syndrome treated in our hospital from April 2019 to July 2021 were included. Of these, 64 control cases were treated with noninvasive positive pressure ventilation and 73 observation cases were treated with PS combined with noninvasive positive pressure ventilation. The expression of KRT-14 and ET-1 in the two groups was compared. The deaths, complications, and PaO₂, PaCO₂, and PaO₂/FiO₂ blood gas indexes in the two groups were compared. Receiver operating characteristic curve (ROC) analysis was used to determine the diagnostic value of KRT-14 and ET-1 in the treatment of NRDS.

RESULTS

The observation group had a significantly higher effectiveness rate than the control group. There was no significant difference between the two groups in terms of neonatal mortality and adverse reactions, such as bronchial dysplasia, cyanosis, and shortness of breath. After treatment, the levels of PaO₂ and PaO₂/FiO₂ in both groups were significantly higher than before treatment, while the level of PaCO₂ was significantly lower. After treatment, the observation group had significantly higher levels of PaO₂ and PaO₂/FiO₂ than the control group, while PaCO₂ was notably lower in the observation group. After treatment, the KRT-14 and ET-1 levels in both groups were significantly decreased compared with the pre-treatment levels. The observation group had a reduction of KRT-14 and ET-1 levels than the control group. ROC curve analysis showed that the area under the curve (AUC) of KRT-14 was 0.791, and the AUC of ET-1 was 0.816.

CONCLUSION

Combining PS with noninvasive positive pressure ventilation significantly improved the effectiveness of NRDS therapy. KRT-14 and ET-1 levels may have potential as therapeutic and diagnostic indicators.

Pulmonary drug delivery devices and nanosystems as potential treatment strategies for acute respiratory distress syndrome (ARDS)

Despite advances in drug delivery technologies, treating acute respiratory distress syndrome (ARDS) is challenging due to pathophysiological barriers such as lung injury, oedema fluid build-up, and lung inflammation. Active pharmaceutical ingredients (API) can be delivered directly to the lung site of action with the use of aerosol-based drug delivery devices, and this circumvents the hepatic first-pass effect and improves the bioavailability of drugs. This review discusses the various challenges and barriers for pulmonary drug delivery, current interventions for delivery, considerations for effective drug delivery, and the use of nanoparticle drug delivery carriers as potential strategies for delivering therapeutics in ARDS. Nanosystems have the added benefit of entrapping drugs, increase pulmonary drug bioavailability, and using biocompatible and biodegradable excipients that can facilitate targeted and/or controlled delivery. These systems provide an alternative to existing conventional systems. An effective way to deliver drugs for the treatment of ARDS can be by using colloidal systems that are aerosolized or inhaled. Drug distribution to the deeper pulmonary tissues is necessary due to the significant endothelial cell destruction that is prevalent in ARDS. The particle size of nanoparticles (<0.5 μm) makes them ideal candidates for treating ARDS as they can reach the alveoli. A look into the various potential benefits and limitations of nanosystems used for other lung disorders is also considered to indicate how they may be useful for the potential treatment of ARDS.

Study on the Efficacy and Safety of Ambroxol Combined with Methylprednisolone in Patients with Acute Lung Injury

Background

There is no better treatment method towards paraquat-induced acute lung injury (ALI) at present. Ambroxol combined with methylprednisolone exhibits a significant improvement effect on ALI treatment, whereas their mechanism in ALI is still unclear.

Methods

64 patients with ALI caused by paraquat poisoning brought to our hospital from January 2015 to January 2018 were selected. They were separated into a combined treatment group (CTG) and a routine treatment group (RTG) on the basis of different treatment methods. The survival of patients was observed after 7 days of treatment. Arterial blood gas, oxygen partial pressure (PaO₂), partial pressure of carbon dioxide (PaCO₂), oxygenation index (PaO₂/FiO₂), patient's spontaneous respiratory rate (RR), tidal volume (VT), and positive end-expiratory pressure (PEEP) were observed before and after treatment for 7 days. Interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) were analyzed. The differences of indexes between the dead patients and the survivors were observed, and the potential predictive value of death was analyzed.

Results

After treatment, the indexes of patients were significantly improved in both groups compared with those before therapy. Further comparison showed that the improvement of PaO₂, PaCO₂, and PaO₂/FiO₂ in CTG was obviously higher than that in RTG (p < 0.05). The improvement of RR, PEEP, and VT in CTG was obviously higher than that in RTG (p < 0.05). The decreased degree of IL-6 and TNF-α in CTG was higher than that in RTG (p < 0.05). The 7-day mortality rate of 64 patients was 39.06%, and there was no obvious difference in the 7-day survival rate in both groups (p = 0.649). IL-6 and TNF-α were expected to be potential prediction indexes of paraquat-induced ALI.

Conclusion

Ambroxol combined with methylprednisolone significantly improved the oxygen partial pressure and oxygenation index of patients with paraquat-induced ALI and inhibited the inflammatory response of patients.

Effects of Pulmonary Surfactant Combined with Noninvasive Positive Pressure Ventilation on KRT-14 and ET-1 Levels in Peripheral Blood and Therapeutic Effects in Neonates with Respiratory Distress Syndrome

This study is aimed at exploring the effect of pulmonary surfactant (PS) combined with noninvasive positive pressure ventilation on the levels of Keratin-14 (KRT-14) and Endothelin-1 (ET-1) in peripheral blood and the therapeutic effect of neonatal respiratory distress syndrome (NRDS). Altogether 137 cases of neonates with respiratory distress syndrome treated in our hospital from April 2016 to July 2018 were collected. Among them, 64 cases treated with noninvasive positive pressure ventilation were considered as the control group, and 73 cases treated with PS combined with noninvasive positive pressure ventilation were considered as the observation group. The expression of KRT-14 and ET-1 in the two groups was compared. The therapeutic effect, death, complications, and blood gas indexes PaO2, PaCO2, and PaO2/FiO2 in the two groups were compared. Receiver operating characteristic curve (ROC) was applied to analyze the diagnostic value of KRT-14 and ET-1 in the therapeutic effect of NRDS. The effective rate of the observation group was higher than that of the control group. After treatment, PaO2 and PaO2/FiO2 in both groups were notably higher than that before treatment, while PaCO2 was notably lower than that before treatment. And after treatment, the levels of PaO2 and PaO2/FiO2 in the observation group were remarkably higher than that in the control group; PaCO2 was notably lower than that in the control group. After treatment, the levels of KRT-14 and ET-1 in the two groups were remarkably lower than those before treatment, and the levels of KRT-14 and ET-1 in the observation group were considerably lower than those in the control group after treatment. ROC curve showed that the area under the curve (AUC) of KRT-14 was 0.791, and the AUC of ET-1 was 0.816. PS combined with noninvasive positive pressure ventilation can notably improve the therapeutic effect of NRDS. KRT-14 and ET-1 levels may be potential therapeutic diagnostic indicators.

SARS-CoV-2 and SARS-CoV Spike-Mediated Cell-Cell Fusion Differ in Their Requirements for Receptor Expression and Proteolytic Activation

Severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) infects cells through interaction of its spike protein (SARS2-S) with angiotensin-converting enzyme 2 (ACE2) and activation by proteases, in particular transmembrane protease serine 2 (TMPRSS2). Viruses can also spread through fusion of infected with uninfected cells. We compared the requirements of ACE2 expression, proteolytic activation, and sensitivity to inhibitors for SARS2-S-mediated and SARS-CoV-S (SARS1-S)-mediated cell-cell fusion. SARS2-S-driven fusion was moderately increased by TMPRSS2 and strongly by ACE2, while SARS1-S-driven fusion was strongly increased by TMPRSS2 and less so by ACE2 expression. In contrast to that of SARS1-S, SARS2-S-mediated cell-cell fusion was efficiently activated by batimastat-sensitive metalloproteases. Mutation of the S1/S2 proteolytic cleavage site reduced effector cell-target cell fusion when ACE2 or TMPRSS2 was limiting and rendered SARS2-S-driven cell-cell fusion more dependent on TMPRSS2. When both ACE2 and TMPRSS2 were abundant, initial target cell-effector cell fusion was unaltered compared to that of wild-type (wt) SARS2-S, but syncytia remained smaller. Mutation of the S2 cleavage (S2') site specifically abrogated activation by TMPRSS2 for both cell-cell fusion and SARS2-S-driven pseudoparticle entry but still allowed for activation by metalloproteases for cell-cell fusion and by cathepsins for particle entry. Finally, we found that the TMPRSS2 inhibitor bromhexine, unlike the inhibitor camostat, was unable to reduce TMPRSS2-activated cell-cell fusion by SARS1-S and SARS2-S. Paradoxically, bromhexine enhanced cell-cell fusion in the presence of TMPRSS2, while its metabolite ambroxol exhibited inhibitory activity under some conditions. On Calu-3 lung cells, ambroxol weakly inhibited SARS2-S-driven lentiviral pseudoparticle entry, and both substances exhibited a dose-dependent trend toward weak inhibition of authentic SARS-CoV-2.IMPORTANCE Cell-cell fusion allows viruses to infect neighboring cells without the need to produce free virus and contributes to tissue damage by creating virus-infected syncytia. Our results demonstrate that the S2' cleavage site is essential for activation by TMPRSS2 and unravel important differences between SARS-CoV and SARS-CoV-2, among those, greater dependence of SARS-CoV-2 on ACE2 expression and activation by metalloproteases for cell-cell fusion. Bromhexine, reportedly an inhibitor of TMPRSS2, is currently being tested in clinical trials against coronavirus disease 2019. Our results indicate that bromhexine enhances fusion under some conditions. We therefore caution against the use of bromhexine in high dosages until its effects on SARS-CoV-2 spike activation are better understood. The related compound ambroxol, which similarly to bromhexine is clinically used as an expectorant, did not exhibit activating effects on cell-cell fusion. Both compounds exhibited weak inhibitory activity against SARS-CoV-2 infection at high concentrations, which might be clinically attainable for ambroxol.

Co-aerosolized Pulmonary Surfactant and Ambroxol for COVID-19 ARDS Intervention: What Are We Waiting for?

After more than 225 days of the first reports of the novel coronavirus from China, COVID-19 pandemic is still on surge. The search for an effective and efficient therapeutic and pharmaceutical intervention is as important and urgent now as it was on Day 1. Majority of the efforts in this direction are toward finding small molecule interventions via repurposing or redirecting the therapeutic approaches. This hypothesis proposes a physical intervention approach directed toward rescuing the complex lung pathology observed in COVID-19 related acute respiratory distress syndrome (CARDS). The loss of content as well as the synthesis and turnover of the surfactant in ARDS has been termed as a "collateral damage." A synergistic, early stage, cost-effective, pharmaceutically viable, safe, and immediately available solution is hence required. The effectiveness of exogenous surfactant treatment in ARDS has been marred with several limitations as pointed out in various clinical trials and require revised protocols related to surfactant dose and mode of delivery. This hypothesis proposes aerosolized surfactant delivery taking the optimal dosing and coating costs into account along with co-delivery of ambroxol to provide synergistic benefits. Ambroxol is reported to have anti-inflammatory, -oxidant, -viral, and -bacterial activities and has a direct impact on the production and secretion of the surfactant from the alveolar Type 2 cells. If aerosolized, atomized, or nebulized in the form of ambroxol-loaded phospholipid nanovesicles at the early stages of ARDS, depleted surfactant levels may be reinstated and surfactant turnover can be initiated and maintained. The ability to deliver both the components in aerosolized-nebulized form may have a huge impact on alleviating the healthcare burden in low resource settings where the availability of ventilators is limited. In conclusion, the surfactant-ambroxol co-aerosolized intervention approach hypothesized here has implications reaching to clinical and pharmaceutical translation worldwide.

Ambroxol and Ciprofloxacin Show Activity Against SARS-CoV2 in Vero E6 Cells at Clinically-Relevant Concentrations

We studied the activity of a range of weakly basic and moderately lipophilic drugs against SARS CoV2 in Vero E6 cells, using Vero E6 survival, qPCR of viral genome and plaque forming assays. No clear relationship between their weakly basic and hydrophobic nature upon their activity was observed. However, the approved drugs ambroxol and ciprofloxacin showed potent activity at concentrations that are clinically relevant and within their known safety profiles, and so may provide potentially useful agents for preclinical and clinical studies in COVID-19.

Efficacy of high-dose ambroxol for paraquat poisoning: A meta-analysis of randomized controlled trials

Background:

Paraquat (PQ) poisoning is characterized by rapidly progressive acute poisoning with high mortality and no specific antidote. Although some clinical studies have been conducted to investigate the benefits of high-dose ambroxol as an adjuvant treatment for PQ poisoning, the efficacy is controversial.

Materials and Methods:

After searching for relevant articles in English and Chinese databases from 1978 to 2019 according to the keywords (paraquat poisoning/methy viologen/gramoxone, and ambroxol/mucosolvan/Bromhexine), we found seven articles that met our inclusion and exclusion criteria. A meta-analysis was performed using fixed-effects model and random-effects model according to the I² value in Stata software (version 15.0). Four outcome indicators (hospital mortality, partial pressure of oxygen (PaO₂), oxygenation index (PaO₂/FiO₂), and survival time of the deceased patients) were of interest to us.

Results:

The meta-analysis showed that adjuvant treatment with high doses of ambroxol increased PaO₂ (weighted mean difference [WMD] = 13.73 [mmHg], 95% confidence interval [CI]: 8.68–18.79, Z = 11.80, P < 0.001), PaO₂/FiO₂ (WMD = 38.81 [mmHg], 95% CI: 29.85–47.76, Z = 8.49, P = 0.000), and survival time of the deceased patients (WMD = 2.58 [d], 95% CI: 0.97–4.18, Z = 3.15, P = 0.002) compared with usual treatment. Treatment with high doses of ambroxol also appeared to reduce the hospital mortality (relative risk = 0.69, 95% CI: 0.55–0.86, Z = 3.25, P = 0.001).

Conclusion:

This study found that high-dose ambroxol is an effective therapy for PQ poisoning and may reduce the in-hospital mortality.

Efficacy of pulmonary surfactant combined with high-dose ambroxol hydrochloride in the treatment of neonatal respiratory distress syndrome

Clinical efficacy of pulmonary surfactant combined with high-dose ambroxol hydrochloride in the treatment of neonatal respiratory distress syndrome (NRDS) was investigated. One hundred child patients with NRDS in Linyi Central Hospital were collected according to the diagnostic criteria for RDS in the Pediatrics, and randomly divided into the treatment group (n=50) and the control group (n=50) based on different therapeutic methods. Patients in the control group were treated with basic treatment and high-dose ambroxol hydrochloride injection, while those in the treatment group were additionally administered with pulmonary surfactant Curosurf based on conventional therapy in the control group. The chest X-rays were collected before the treatment and at 12 h after the drug administration, the degree of respiratory distress in child patients was observed and evaluated via Silverman grading, and changes in blood gas indexes were recorded before treatment and at 2, 6 and 12 h after the drug administration. The chest X-ray grade, Silverman grade and blood gas analysis results had no differences between the two groups before the treatment (P>0.05). In the treatment group, partial pressure of oxygen (PaO₂) and PH were increased and partial pressure of carbon dioxide (PaCO₂) was decreased compared with those in the control group at 2, 6 and 12 h after the drug administration (P<0.05). At 12 h after the drug administration, chest X-ray grade and Silverman grade in both groups were improved, which were significantly superior in the treatment group to those in the control group (P<0.01). Moreover, the efficacy in the treatment group was remarkably better than that in the control group at 12 h after drug administration (P<0.01). Pulmonary surfactant combined with high-dose ambroxol hydrochloride has definite efficacy in the treatment of NRDS, which can significantly improve the pulmonary infection, respiratory distress and blood gas indexes of child patients.

Enhancement of lung levels of antibiotics by ambroxol and bromhexine

INTRODUCTION

Major unmet needs remain for improved antibiotic treatment in lung infections. While development of new antibiotics is needed to overcome resistance, other approaches to optimize therapy using existing agents are also attractive. Ambroxol induces lung autophagy at human-relevant doses and improves lung levels of several approved antibiotics. Areas covered: This review discusses preclinical and clinical studies of the effects of ambroxol (and its prodrug precursor bromhexine) co-treatment upon levels of antibiotics in lung tissue, sputum, and bronchoalveolar lavage fluid. Expert opinion: Ambroxol co-treatment is associated with significant increases in lung tissue and airway surface fluid levels of a range of antibiotics including beta lactams, glycopeptides, macrolides, nitrofurans, and rifamycins. In most cases, the increased levels are only modest and are insufficient to overcome high-level resistance against that same antibiotic class, and so co-treatment with ambroxol is unlikely to alter clinical outcomes. Additionally, for most antibiotics there is no evidence that outcomes in non-resistant disease are improved by higher drug levels, and there is limited efficacy of co-treatment of antibiotics with ambroxol for most pathogens. The two cases where ambroxol may improve therapy are rifampin-sensitive tuberculosis and non-tuberculous mycobacterial infection, and vancomycin sensitive methicillin resistant Staphylococcus aureus pneumonia.

Antenatal maternal medication administration in preventing respiratory distress syndrome of premature infants: A network meta-analysis

INTRODUCTION

High incidence of respiratory distress syndrome (RDS) was revealed in preterm infants, which acted as one of the main factors that led to infant death.

OBJECTIVES

This network meta-analysis (NMA) was performed to rank the efficacy of different therapies in preventing for premature infants.

METHODS

PubMed, Embase, Cochrane Library, CINAHL, and CNKI were searched. Statistical analysis was performed using STATA statistical software (Version 12.0). Odds ratios (ORs) with 95% credible intervals (95%CrIs) were applied to evaluate relative efficacy of various treatments. Ranking of probabilities of each treatment was illustrated by surface under the cumulative ranking curve (SUCRA). Consistency between direct and indirect evidence was assessed using the node-splitting plots and heat plots.

RESULTS AND CONCLUSION

A total of 48 trials were eligible to evaluate the efficacy of 3 interventions including ambroxol (AMB), betamethasone (BET), and dexamethasone (DEX). Three outcomes including the incidence of RDS, bronchopulmonary dysplasia (BPD) and neonatal death were assessed. Compared with placebo, BET, DEX, and AMB all demonstrated better efficacy in terms of preventing RDS and neonatal death. No significant difference among treatments was found in the assessment of the incidence of BPD. According to SUCRA, AMB was the optimal treatment in preventing RDS and neonatal death. Besides, no significant inconsistency was detected between direct and indirect evidence. To conclude, no significant difference was found among these three medications. AMB seems to have the potential to be the most effective treatment for reducing the incidence of RDS and neonatal death.

Ambroxol for the treatment of fibromyalgia: science or fiction?

Fibromyalgia appears to present in subgroups with regard to biological pain induction, with primarily inflammatory, neuropathic/neurodegenerative, sympathetic, oxidative, nitrosative, or muscular factors and/or central sensitization. Recent research has also discussed glial activation or interrupted dopaminergic neurotransmission, as well as increased skin mast cells and mitochondrial dysfunction. Therapy is difficult, and the treatment options used so far mostly just have the potential to address only one of these aspects. As ambroxol addresses all of them in a single substance and furthermore also reduces visceral hypersensitivity, in fibromyalgia existing as irritable bowel syndrome or chronic bladder pain, it should be systematically investigated for this purpose. Encouraged by first clinical observations of two working groups using topical or oral ambroxol for fibromyalgia treatments, the present paper outlines the scientific argument for this approach by looking at each of the aforementioned aspects of this complex disease and summarizes putative modes of action of ambroxol. Nevertheless, at this point the evidence basis for ambroxol is not strong enough for clinical recommendation.

[More than expectorant: new scientific data on ambroxol in the context of the treatment of bronchopulmonary diseases]

BACKGROUND

Ambroxol has been established for decades in the treatment of acute and chronic respiratory diseases. In 2015, the European Medicines Agency reassessed the clinical benefit-risk ratio of the drug.

OBJECTIVE

What new scientific data on ambroxol, which are relevant to the treatment of bronchopulmonary diseases, are available?

METHOD

The review is based on a systematic literature research in medline with the search term "ambroxol" during the publication period 2006-2015. Non-relevant publications were excluded manually.

RESULTS AND CONCLUSIONS

Ambroxol is still intensively researched. The traditional indication as an expectorant is confirmed. But there is also an ever better understanding of the various mechanisms of action as well as the ever more exact modeling of the structures under investigation. New fields of application are conceivable, e. g. in patients with severe pulmonary disease who undergo surgery or who are in intensive care, as an adjuvant in anti-infective therapies, especially in infections with biofilm-producing pathogens, or in rare diseases such as lysosomal storage diseases. However, final evidence of the clinical relevance in these fields of application is still missing.

Ambroxol Hydrochloride Combined with Fluconazole Reverses the Resistance of Candida albicans to Fluconazole

In this study, we found that ambroxol hydrochloride (128 μg/mL) exhibits synergistic antifungal effects in combination with fluconazole (2 μg/mL) against resistant planktonic Candida albicans (C. albicans) cells. This combination also exhibited synergistic effects against resistant C. albicans biofilms in different stages (4, 8, and 12 h) according to the microdilution method. In vitro data were further confirmed by the success of this combination in treating Galleria mellonella infected by resistant C. albicans. With respect to the synergistic mechanism, our result revealed that ambroxol hydrochloride has an effect on the drug transporters of resistant C. albicans, increasing the uptake and decreasing the efflux of rhodamine 6G, a fluorescent alternate of fluconazole. This is the first study to investigate the in vitro and in vivo antifungal effects, as well as the possible synergistic mechanism of ambroxol hydrochloride in combination with fluconazole against resistant C. albicans. The results show the potential role for this drug combination as a therapeutic alternative to treat resistant C. albicans and provide insights into the development of antifungal targets and new antifungal agents.