Dextran sulfate as a leukocyte-endothelium adhesion molecule inhibitor of lung injury in pediatric open-heart surgery

A low molecular weight dextran sulphate, ILB®, for the treatment of amyotrophic lateral sclerosis (ALS): An open-label, single-arm, single-centre, phase II trial

BACKGROUND

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig´s disease, is a rare neurological condition and is the most common motor neurone disease. It is a fatal disease with specific loss of motor neurons in the spinal cord, brain stem, and motor cortex leading to progressive paralysis and usually death within five years of diagnosis. There remains no cure for ALS, and management is focused on a combination of neuroprotective medication, respiratory support, and management by multidisciplinary clinics.

PATIENTS AND METHODS

This prospective, single-arm, open-label phase II clinical trial of sustained weekly administration of 2 mg/kg ILB® (a low-molecular weight dextran sulphate) was conducted in a single UK hospital. Eligible patients were at least 18 years and had a definite diagnosis of ALS according to El Escorial Criteria. The co-primary outcomes were safety, tolerability, and quantity of ILB® administered. EudraCT number. 2018-000668-28.

FINDINGS

Between 18-Apr-2019 and 27-Mar-2020, 11 patients were recruited and treated for up to 38 weeks. There were no treatment terminations or withdrawals. One serious adverse event was reported, which was not related to ILB® and resolved without sequalae. 270 mild/moderate adverse events were reported with no intolerable events occurring during the trial. The total number of ILB® treatments administered per patient ranged from 4 to 38, with a cumulative dose ranging from 745 to 6668 mg. As a result of the COVID-19 pandemic and the high-risk status of study participants, recruitment and treatment was suspended early in Mar-2020. At the long-term follow-up, three patients had died after the trial was halted, between 53 and 62 weeks after their final ILB® injection.

INTERPRETATION

Long-term weekly ILB® injections of 2 mg/kg was well tolerated and had an acceptable safety profile in patients with ALS.

TRIAL REGISTRATION

EudraCT: 2018-000668-28. clinicaltrials.gov: NCT03705390. This trial adheres to the principles of GCP in the design, conduct, recording and reporting of clinical trials as listed in part 2, "Conditions and Principles which apply to all Clinical Trials" under the header "Principles based on Articles 2 to 5 of the EU GCP Directive" in the Medicines for Human Use Clinical Trials Regulations (as amended in SI 2006/1928). For clarity, the study did not conform to all aspects of the International Conference on Harmonisation (ICH) E6 R2 Guidelines for GCP (also known as 'ICH GCP'). Of note, we did not use an external database, perform 100% source data verification, and only primary outcome data were analysed in parallel by a second, independent statistician.

A hydrogel engineered to deliver minocycline locally to the injured cervical spinal cord protects respiratory neural circuitry and preserves diaphragm function

We tested a biomaterial-based approach to preserve the critical phrenic motor circuitry that controls diaphragm function by locally delivering minocycline hydrochloride (MH) following cervical spinal cord injury (SCI). MH is a clinically-available antibiotic and anti-inflammatory drug that targets a broad range of secondary injury mechanisms via its anti-inflammatory, anti-oxidant and anti-apoptotic properties. However, MH is only neuroprotective at high concentrations that cannot be achieved by systemic administration, which limits its clinical efficacy. We have developed a hydrogel-based MH delivery system that can be injected into the intrathecal space for local delivery of high concentrations of MH, without damaging spinal cord tissue. Implantation of MH hydrogel after unilateral level-C4/5 contusion SCI robustly preserved diaphragm function, as assessed by in vivo recordings of compound muscle action potential (CMAP) and electromyography (EMG) amplitudes. MH hydrogel also decreased lesion size and degeneration of cervical motor neuron somata, demonstrating its central neuroprotective effects within the injured cervical spinal cord. Furthermore, MH hydrogel significantly preserved diaphragm innervation by the axons of phrenic motor neurons (PhMNs), as assessed by both detailed neuromuscular junction (NMJ) morphological analysis and retrograde PhMN labeling from the diaphragm using cholera toxin B (CTB). In conclusion, our findings demonstrate that local MH hydrogel delivery to the injured cervical spinal cord is effective in preserving respiratory function after SCI by protecting the important neural circuitry that controls diaphragm activation.

Local BDNF Delivery to the Injured Cervical Spinal Cord using an Engineered Hydrogel Enhances Diaphragmatic Respiratory Function

We developed an innovative biomaterial-based approach to repair the critical neural circuitry that controls diaphragm activation by locally delivering brain-derived neurotrophic factor (BDNF) to injured cervical spinal cord. BDNF can be used to restore respiratory function via a number of potential repair mechanisms; however, widespread BDNF biodistribution resulting from delivery methods such as systemic injection or lumbar puncture can lead to inefficient drug delivery and adverse side effects. As a viable alternative, we developed a novel hydrogel-based system loaded with polysaccharide-BDNF particles self-assembled by electrostatic interactions that can be safely implanted in the intrathecal space for achieving local BDNF delivery with controlled dosing and duration. Implantation of BDNF hydrogel after C4/C5 contusion-type spinal cord injury (SCI) in female rats robustly preserved diaphragm function, as assessed by in vivo recordings of compound muscle action potential and electromyography amplitudes. However, BDNF hydrogel did not decrease lesion size or degeneration of cervical motor neuron soma, suggesting that its therapeutic mechanism of action was not neuroprotection within spinal cord. Interestingly, BDNF hydrogel significantly preserved diaphragm innervation by phrenic motor neurons (PhMNs), as assessed by detailed neuromuscular junction morphological analysis and retrograde PhMN labeling from diaphragm using cholera toxin B. Furthermore, BDNF hydrogel enhanced the serotonergic axon innervation of PhMNs that plays an important role in modulating PhMN excitability. Our findings demonstrate that local BDNF hydrogel delivery is a robustly effective and safe strategy to restore diaphragm function after SCI. In addition, we demonstrate novel therapeutic mechanisms by which BDNF can repair respiratory neural circuitry.SIGNIFICANCE STATEMENT Respiratory compromise is a leading cause of morbidity and mortality following traumatic spinal cord injury (SCI). We used an innovative biomaterial-based drug delivery system in the form of a hydrogel that can be safely injected into the intrathecal space for achieving local delivery of brain-derived neurotrophic factor (BDNF) with controlled dosing and duration, while avoiding side effects associated with other delivery methods. In a clinically relevant rat model of cervical contusion-type SCI, BDNF hydrogel robustly and persistently improved diaphragmatic respiratory function by enhancing phrenic motor neuron (PhMN) innervation of the diaphragm neuromuscular junction and by increasing serotonergic innervation of PhMNs in ventral horn of the cervical spinal cord. These exciting findings demonstrate that local BDNF hydrogel delivery is a safe and robustly effective strategy to maintain respiratory function after cervical SCI.

Investigation of pulmonary involvement in inflammatory bowel disease in an experimental model of colitis

BACKGROUND/AIMS

Inflammatory bowel disease (IBD) may also involve various extra-intestinal organs. Clinical studies have found asymptomatic/symptomatic pulmonary involvement in 1% to 6% of patients with IBD. The present study histopathologically investigated pulmonary involvement in an experimental model of colitis in order to demonstrate pulmonary tissue involvement in IBD and to expose potential etiological factors. It also explored the relation between inflammation and tissue concentrations of vascular endothelial growth factor (VEGF) and tumor necrosis factor α (TNF-α).

METHODS

The study comprised 24 male Wistar albino rats. The rats were divided into four groups of six rats each. Acute colitis was induced in two separate groups using either the dextran sulphate sodium (DSS) or trinitrobenzene sulfonic acid (TNBS) method, while the other two groups were used as controls for each model of colitis. Wallace scoring was used for macroscopic assessment of colitis, and the lungs were histopathologically examined. Concentrations of VEGF and TNF-α in pulmonary tissue were measured by the enzyme-linked immunosorbent assay method.

RESULTS

The number of animals that had alveolar hemorrhage was significantly higher in the TNBS-induced colitis and DSS-induced colitis groups compared to their own control groups (p = 0.015 and p = 0.015, respectively). VEGF and TNF-α concentrations in pulmonary tissues were significantly increased in both the TNBS colitis and DSS colitis groups compared to their own control groups (p = 0.002 and p = 0.004, respectively; and p = 0.002 and p = 0.002, respectively).

CONCLUSIONS

The present study demonstrated that significant and serious histopathological changes directly associated with colitis occur in the lungs in IBD.

Plasma sRAGE enables prediction of acute lung injury after cardiac surgery in children

Introduction

Acute lung injury (ALI) after cardiac surgery is associated with a high postoperative morbidity and mortality, but few predictors are known for the occurrence of the complication. This study evaluated whether elevated plasma levels of soluble receptor for advanced glycation end products (sRAGE) and S100A12 reflected impaired lung function in infants and young children after cardiac surgery necessitating cardiopulmonary bypass (CPB).

Methods

Consecutive children younger than 3 years after cardiac surgery were prospectively enrolled and assigned to ALI and non-ALI groups, according to the American-European Consensus Criteria. Plasma concentrations of sRAGE and S100A12 were measured at baseline, before, and immediately after CPB, as well as 1 hour, 12 hours, and 24 hours after operation.

Results

Fifty-eight patients were enrolled and 16 (27.6%) developed postoperative ALI. Plasma sRAGE and S100A12 levels increased immediately after CPB and remained significantly higher in the ALI group even 24 hour after operation (P < 0.01). In addition, a one-way MANOVA revealed that the overall sRAGE and S100A12 levels were higher in the ALI group than in the non-ALI group immediately after CPB (P < 0.001). The multivariate logistic regression analysis showed that the plasma sRAGE level immediately after CPB was an independent predictor for postoperative ALI (OR, 1.088; 95% CI, 1.011 to 1.171; P = 0.025). Increased sRAGE and S100A12 levels immediately after CPB were significantly correlated with a lower PaO₂/FiO₂ ratio (P < 0.01) and higher radiographic lung-injury score (P < 0.01), as well as longer mechanical ventilation time (sRAGE_N: r = 0.405; P = 0.002; S100A12_N: r = 0.322; P = 0.014), longer surgical intensive care unit stay (sRAGE_N: r = 0.421; P = 0.001; S100A12_N: r = 0.365; P = 0.005) and hospital stay (sRAGE_N: r = 0.329; P = 0.012; S100A12_N: r = 0.471; P = 0.001).

Conclusions

Elevated sRAGE and S100A12 levels correlate with impaired lung function, and sRAGE is a useful early biomarker of ALI in infants and young children undergoing cardiac surgery.

Effects of breviscapine on pulmonary inflammatory response and lung injury in children undergoing open heart surgery

This study examined the effects of breviscapine (1) on pulmonary inflammatory response and lung function in pediatric patients undergoing open heart surgery. Forty-five children (ASA II or III, aged 2-72 months) were randomly assigned to control group (saline, Group C), low dose 1 group (0.5 mg/kg, Group Bre0.5), and high dose 1 group (1.0 mg/kg, Group Bre1.0), 15 cases each group. Plasma concentrations of procalcitonin (PCT) and neutrophil elastase (NE) were measured and compared at different time points. Plasma concentrations of PCT and NE were increased after cardiopulmonary bypass (CPB) induction, and the concentrations were lower in 1-treated groups. The present results indicated that continuous infusion of 1 before the CPB suppressed the production of PCT and NE attenuated systemic inflammatory response, which could result in lung protective effect in children undergoing open heart surgery.

Cardiopulmonary bypass and edema: physiology and pathophysiology

Edema is a common morbidity following cardiopulmonary bypass (CPB) and can result in injury to many organs, including the heart, lungs, and brain. Generalized edema is also common and can lead to increased post-operative hospital stay and other morbidities. Pediatric patients are more susceptible to post-CPB edema and the consequences are more severe for this population. Hemodilution and systemic inflammatory responses are two suspected causes of CPB-related edema; however, the mechanisms involved are far from understood. Also, the common strategies to improve edema have not been completely successful and there is a need for new strategies at maintaining a fluid balance of patients as close to physiological as possible, especially for pediatric patients. An integrative approach to understanding edema is necessary as the forces involved in fluid homeostasis are dynamic and interdependent. Therefore, this review will focus on the physiology of fluid homeostasis and the pathologies of fluid shifts during CPB which lead to general edema as well as tissue-specific edema.