Therapeutic effects of inhaling aerosolized surfactant alone or with dexamethasone generated by a novel noninvasive apparatus on acute lung injury in rats

Pulmonary surfactant as a versatile biomaterial to fight COVID-19

The COVID-19 pandemic has wielded an enormous pressure on global health care systems, economics and politics. Ongoing vaccination campaigns effectively attenuate viral spreading, leading to a reduction of infected individuals, hospitalizations and mortality. Nevertheless, the development of safe and effective vaccines as well as their global deployment is time-consuming and challenging. In addition, such preventive measures have no effect on already infected individuals and can show reduced efficacy against SARS-CoV-2 variants that escape vaccine-induced host immune responses. Therefore, it is crucial to continue the development of specific COVID-19 targeting therapeutics, including small molecular drugs, antibodies and nucleic acids. However, despite clear advantages of local drug delivery to the lung, inhalation therapy of such antivirals remains difficult. This review aims to highlight the potential of pulmonary surfactant (PS) in the treatment of COVID-19. Since SARS-CoV-2 infection can progress to COVID-19-related acute respiratory distress syndrome (CARDS), which is associated with PS deficiency and inflammation, replacement therapy with exogenous surfactant can be considered to counter lung dysfunction. In addition, due to its surface-active properties and membrane-interaction potential, PS can be repurposed to enhance drug spreading along the respiratory epithelium and to promote intracellular drug delivery. By merging these beneficial features, PS can be regarded as a versatile biomaterial to combat respiratory infections, in particular COVID-19.

Aerosolized Beractant in neonatal respiratory distress syndrome: A randomized fixed-dose parallel-arm phase II trial

PURPOSE

There is increasing research into novel techniques of administering surfactant to preterm infants (PTIs) with respiratory distress syndrome (RDS) receiving non-invasive respiratory support (NIRS). Although aerosolized surfactant (AS) is promising in PTIs receiving NIRS, the optimal surfactant dose and formulation, drug-device combination and patient profile is not known. The objective of this randomized clinical trial was to investigate the feasibility, safety, efficacy and impact of four dosing schedules of AS using two nebulizers in PTIs with RDS stratified by gestational age (GA).

METHODS

PTIs with RDS receiving pre-defined NIRS for ≤8 h were assigned to 4 A S dosing schedules and 2 nebulizers within three GA strata (I = 24^0/7-28^6/7, II = 29^0/7-32^6/7, III = 33^0/7-36^6/7 weeks). There was no contemporaneous control group; at the recommendation of the Data Monitoring Committee, data was collected retrospectively for control infants.

RESULTS

Of 149 subjects that received AS, the median age at initiation of the 1st dose and duration was 5.5 and 2.4 h respectively. There were 29 infants in stratum I, and 60 each in strata II and III. Of infants <32 weeks GA, 94% received caffeine prior to AS. Fifteen infants (10%) required intubation within 72 h; the rates were not significantly different between GA strata, dosing schedules and nebulizers for infants who received aerosolized surfactant. Compared to retrospective controls, infants who received AS were less likely to need intubation within 72 h in both the intention-to-treat (32% vs. 11%) and the per-protocol (22% vs. 10%) analyses (p < 0.05) with GA stratum specific differences. AS was well tolerated by infants and clinical caregivers. Commonest adverse events included surfactant reflux from nose and mouth (18%), desaturations (11%), and increased secretions (7%).

CONCLUSIONS

We have demonstrated the feasibility, absence of serious adverse events and short-term efficacy of four dosing schedules of AS in the largest Phase II clinical trial of PTIs 24-36 weeks' GA with RDS receiving NIRS (ClinicalTrials.gov NCT02294630). The commonest adverse events noted were surfactant reflux and desaturations; no serious adverse effects were observed. Infants who received AS were less likely to receive intubation within 72 h compared to historical controls. AS is a promising new therapy for PTIs with RDS.

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.

Protective mechanism of sulforaphane in Nrf2 and anti-lung injury in ARDS rabbits

The effect of sulforaphane on nuclear factor erythroid 2-related factor 2 (Nrf2) and its protective mechanism for lung injury in rabbits with acute respiratory distress syndrome (ARDS) were investigated. Thirty rabbits were randomly divided into control (n=10), model (n=10) and experimental groups (n=10). Rabbits in model group and experimental group were treated with femoral venous injection of oleic acid to establish the ARDS model, while those in control group were injected with the same volume of normal saline. The experimental group received intravenous injection of sulforaphane. Twelve hours after modeling, the clinical manifestations and deaths of rabbits in each group were recorded and compared, including blood gas indexes, lung index (LI), alveolar damage coefficient, serum Nrf2 expression, as well as messenger ribonucleic acid (mRNA) and protein expression of Nrf2 in lung tissues. Pink frothy sputum and death were observed in rabbits in model group and experimental group, but the number of such cases in experimental group was smaller than that in the model group (p<0.05). Compared with those in control group, LI and IQA in model group and experimental group were increased, but LI and IQA in the experimental group were significantly decreased compared with those in the model group. Compared with those in the model group, the blood gas indexes (PaO₂, PaCO₂ and SaO₂) in the experimental group were significantly increased (p<0.05). Nrf2 in serum and lung tissues of rabbits in experimental group was significantly increased compared with that in model group (p<0.05). Sulforaphane significantly inhibits ARDS in rabbits and plays a protective role in ARDS through upregulating Nrf2.

Dopamine D1 receptor agonist A-68930 inhibits NLRP3 inflammasome activation and protects rats from spinal cord injury-induced acute lung injury

STUDY DESIGN

Randomized experimental study.

OBJECTIVES

The study aimed to investigate the therapeutic efficacy and molecular mechanisms of A-68930 in a rat model of spinal cord injury (SCI)-induced acute lung injury (ALI).

SETTING

China.

METHODS

The influences of A-68930 on the pulmonary edema, histological changes, proinflammatory cytokines levels, myeloperoxidase (MPO) activity and NLRP3 inflammasome protein expression were estimated.

RESULTS

SCI significantly promoted NLRP3 inflammasome activation, increased proinflammatory cytokine productions and MPO activity, and induced pulmonary edema and tissue damage in the SCI group as compared with the control group. A-68930 administration significantly inhibited NLRP3 inflammasome activation and reduced inflammatory cytokines levels and MPO activity. Moreover, A-68930 administration attenuated pulmonary edema and histopathology.

CONCLUSION

Our experimental findings indicated that A-68930 exhibited a protective effect on SCI-induced ALI by the alleviations of inflammatory response with the inhibition NLRP3 inflammasome activation 72 h post injury. The present study indicated that A-68930 could be a potentially efficient therapeutic strategy for the treatment of SCI-induced ALI.

Sulforaphane exerts anti-inflammatory effects against lipopolysaccharide-induced acute lung injury in mice through the Nrf2/ARE pathway

Sulforaphane (1-isothiocyanate-4-methyl sulfonyl butane) is a plant extract (obtained from cruciferous vegetables, such as broccoli and cabbage) and is known to exert anticancer, antioxidant and anti-inflammatory effects. It stimulates the generation of human or animal cells, which is beneficial to the body. The aim of the current study was to determine whether sulforaphane protects against lipopolysaccharide (LPS)‑induced acute lung injury (ALI) through its anti-inflammatory effects, and to investigate the signaling pathways involved. For this purpose, male BALB/c mice were treated with sulforaphane (50 mg/kg) and 3 days later, ALI was induced by the administration of LPS (5 mg/kg) and we thus established the model of ALI. Our results revealed that sulforaphane significantly decreased lactate dehydrogenase (LDH) activity (as shown by LDH assay), the wet-to-dry ratio of the lungs and the serum levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) (measured by ELISA), as well as nuclear factor-κB protein expression in mice with LPS-induced ALI. Moreover, treatment with sulforaphane significantly inhibited prostaglandin E2 (PGE2) production, and cyclooxygenase-2 (COX-2), matrix metalloproteinase-9 (MMP-9) protein expression (as shown by western blot analysis), as well as inducible nitric oxide synthase (iNOS) activity in mice with LPS-induced ALI. Lastly, we noted that pre-treatment with sulforaphane activated the nuclear factor-E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway in the mice with LPS-induced ALI. These findings demonstrate that sulforaphane exerts protective effects against LPS-induced ALI through the Nrf2/ARE pathway. Thus, sulforaphane may be a potential a candidate for use in the treatment of ALI.