Low molecular weight dextran sulfate (ILB®) administration restores brain energy metabolism following severe traumatic brain injury in the rat

Traumatic brain injury (TBI) is the leading cause of death and disability in people less than 40 years of age in Western countries. Currently, there are no satisfying pharmacological treatments for TBI patients. In this study, we subjected rats to severe TBI (sTBI), testing the effects of a single subcutaneous administration, 30 min post-impact, of a new low molecular weight dextran sulfate, named ILB\uae, at three different dose levels (1, 5, and 15 mg/kg body weight). A group of control sham-operated animals and one of untreated sTBI rats were used for comparison (each group n = 12). On day 2 or 7 post-sTBI animals were sacrificed and the simultaneous HPLC analysis of energy metabolites, N-acetylaspartate (NAA), oxidized and reduced nicotinic coenzymes, water-soluble antioxidants, and biomarkers of oxidative/nitrosative stress was carried out on deproteinized cerebral homogenates. Compared to untreated sTBI rats, ILB\uae improved energy metabolism by increasing ATP, ATP/ adenosine diphosphate ratio (ATP/ADP ratio), and triphosphate nucleosides, dose-dependently increased NAA concentrations, protected nicotinic coenzyme levels and their oxidized over reduced ratios, prevented depletion of ascorbate and reduced glutathione (GSH), and decreased oxidative (malondialdehyde formation) and nitrosative stress (nitrite + nitrate production). Although needing further experiments, these data provide the first evidence that a single post-injury injection of a new low molecular weight dextran sulfate (ILB\uae) has beneficial effects on sTBI metabolic damages. Due to the absence of adverse effects in humans, ILB\uae represents a promising therapeutic agent for the treatment of sTBI patients

ILB® attenuates clinical symptoms and serum biomarkers of oxidative/nitrosative stress and mitochondrial dysfunction in patients with Amyotrophic Lateral Sclerosis

Oxidative/nitrosative stress and mitochondrial dysfunction is a hallmark of amyotrophic lateral sclerosis (ALS), an invariably fatal progressive neurodegenerative disease. Here, as an exploratory arm of a phase II clinical trial (EudraCT Number 2017-005065-47), we used high performance liquid chromatography(HPLC) to investigate changes in the metabolic profiles of serum from ALS patients treated weekly for 4 weeks with a repeated sub-cutaneous dose of 1 mg/kg of a proprietary low molecular weight dextran sulphate, called ILB®. A significant normalization of the serum levels of several key metabolites was observed over the treatment period, including N-acetylaspartate (NAA), oxypurines, biomarkers of oxidative/nitrosative stress and antioxidants. An improved serum metabolic profile was accompanied by significant amelioration of the patients' clinical conditions, indicating a response to ILB® treatment that appears to be mediated by improvement of tissue bioenergetics, decrease of oxidative/nitrosative stress and attenuation of (neuro)inflammatory processes

The mechanism of action of a novel neuroprotective low molecular weight dextran sulphate : new platform therapy for neurodegenerative diseases like Amyotrophic Lateral Sclerosis

Background: Acute and chronic neurodegenerative diseases represent an immense socioeconomic burden that drives the need for new disease modifying drugs. Common pathogenic mechanisms in these diseases are evident, suggesting that a platform neuroprotective therapy may offer effective treatments. Here we present evidence for the mode of pharmacological action of a novel neuroprotective low molecular weight dextran sulphate drug called ILB®. The working hypothesis was that ILB® acts via the activation of heparin-binding growth factors (HBGF). Methods: Pre-clinical and clinical (healthy people and patients with ALS) in vitro and in vivo studies evaluated the mode of action of ILB®. In vitro binding studies, functional assays and gene expression analyses were followed by the assessment of the drug effects in an animal model of severe traumatic brain injury (sTBI) using gene expression studies followed by functional analysis. Clinical data, to assess the hypothesized mode of action, are also presented from early phase clinical trials. Results: ILB® lengthened APTT time, acted as a competitive inhibitor for HGF-Glypican-3 binding, effected pulse release of heparin-binding growth factors (HBGF) into the circulation and modulated growth factor signaling pathways. Gene expression analysis demonstrated substantial similarities in the functional dysregulation induced by sTBI and various human neurodegenerative conditions and supported a cascading effect of ILB® on growth factor activation, followed by gene expression changes with profound beneficial effect on molecular and cellular functions affected by these diseases. The transcriptional signature of ILB® relevant to cell survival, inflammation, glutamate signaling, metabolism and synaptogenesis, are consistent with the activation of neuroprotective growth factors as was the ability of ILB® to elevate circulating levels of HGF in animal models and humans. Conclusion: ILB® releases, redistributes and modulates the bioactivity of HBGF that target disease compromised nervous tissues to initiate a cascade of transcriptional, metabolic and immunological effects that control glutamate toxicity, normalize tissue bioenergetics, and resolve inflammation to improve tissue function. This unique mechanism of action mobilizes and modulates naturally occurring tissue repair mechanisms to restore cellular homeostasis and function. The identified pharmacological impact of ILB® supports the potential to treat various acute and chronic neurodegenerative disease, including sTBI and ALS

ILB ®, a low molecular weight dextran sulphate, restores glutamate omeostasis, amino acid metabolism and neurocognitive functions in a Raht Model of severe traumatic brain injury

In a previous study, we found that administration of ILB®, a new low molecular weight dextran sulphate, significantly improved mitochondrial functions and energy metabolism, as well as decreased oxidative/nitrosative stress, of brain tissue of rats exposed to severe traumatic brain injury (sTBI), induced by the closed-head weight-drop model of diffused TBI. Using aliquots of deproteinized brain tissue of the same animals of this former study, we here determined the concentrations of 24 amino acids of control rats, untreated sTBI rats (sacrificed at 2 and 7 days post-injury) and sTBI rats receiving a subcutaneous ILB® administration (at the dose levels of 1, 5 and 15 mg/kg b.w.) 30 min post-impact (sacrificed at 2 and 7 days post-injury). Additionally, in a different set of experiments, new groups of control rats, untreated sTBI rats and ILB®-treated rats (administered 30 min after sTBI at the dose levels of 1 or 5 mg/kg b.w.) were studied for their neurocognitive functions (anxiety, locomotor capacities, short- and long-term memory) at 7 days after the induction of sTBI. Compared to untreated sTBI animals, ILB® significantly decreased whole brain glutamate (normalizing the glutamate/glutamine ratio), glycine, serine and g-aminobutyric acid. Furthermore, ILB® administration restored arginine metabolism (preventing nitrosative stress), levels of amino acids involved in methylation reactions (methionine, L-cystathionine, S-adenosylhomocysteine), and N-acetylaspartate homeostasis. The macroscopic evidences of the beneficial effects on brain metabolism induced by ILB® were the relevant improvement in neurocognitive functions of the group of animals treated with ILB® 5 mg/kg b.w., compared to the marked cognitive decline measured in untreated sTBI animals. These results demonstrate that ILB® administration 30 min after sTBI prevents glutamate excitotoxicity and normalizes levels of amino acids involved in crucial brain metabolic functions. The ameliorations of amino acid metabolism, mitochondrial functions and energy metabolism in ILB®-treated rats exposed to sTBI produced significant improvement in neurocognitive functions, reinforcing the concept that ILB® is a new effective therapeutic tool for the treatment of sTBI, worth being tested in the clinical setting

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Appropriation of GPIb from platelet-derived extracellular vesicles supports monocyte recruitment in systemic inflammation

Interactions between platelets, leukocytes and the vessel wall provide alternative pathological routes of thrombo-inflammatory leukocyte recruitment. We found that when platelets were activated by a range of agonists in whole blood, they shed platelet-derived extracellular vesicles which rapidly and preferentially bound to blood monocytes compared to other leukocytes. Platelet-derived extracellular vesicle binding to monocytes was initiated by P-selectin-dependent adhesion and was stabilised by binding of phosphatidylserine. These interactions resulted in the progressive transfer of the platelet adhesion receptor GPIbα to monocytes. GPIbα+-monocytes tethered and rolled on immobilised von Willebrand Factor or were recruited and activated on endothelial cells treated with TGF-β1 to induce the expression of von Willebrand Factor. In both models monocyte adhesion was ablated by a function-blocking antibody against GPIbα. Monocytes could also bind platelet-derived extracellular vesicle in mouse blood in vitro and in vivo. Intratracheal instillations of diesel nanoparticles, to model chronic pulmonary inflammation, induced accumulation of GPIbα on circulating monocytes. In intravital experiments, GPIbα+-monocytes adhered to the microcirculation of the TGF-β1-stimulated cremaster muscle, while in the ApoE−/− model of atherosclerosis, GPIbα+-monocytes adhered to the carotid arteries. In trauma patients, monocytes bore platelet markers within 1 hour of injury, the levels of which correlated with severity of trauma and resulted in monocyte clearance from the circulation. Thus, we have defined a novel thrombo-inflammatory pathway in which platelet-derived extracellular vesicles transfer a platelet adhesion receptor to monocytes, allowing their recruitment in large and small blood vessels, and which is likely to be pathogenic

The polymorphism L412F in TLR3 inhibits autophagy and is a marker of severe COVID-19 in males

The polymorphism L412F in TLR3 has been associated with several infectious diseases. However, the mechanism underlying this association is still unexplored. Here, we show that the L412F polymorphism in TLR3 is a marker of severity in COVID-19. This association increases in the sub-cohort of males. Impaired macroautophagy/autophagy and reduced TNF/TNFα production was demonstrated in HEK293 cells transfected with TLR3L412F-encoding plasmid and stimulated with specific agonist poly(I:C). A statistically significant reduced survival at 28 days was shown in L412F COVID-19 patients treated with the autophagy-inhibitor hydroxychloroquine (p = 0.038). An increased frequency of autoimmune disorders such as co-morbidity was found in L412F COVID-19 males with specific class II HLA haplotypes prone to autoantigen presentation. Our analyses indicate that L412F polymorphism makes males at risk of severe COVID-19 and provides a rationale for reinterpreting clinical trials considering autophagy pathways. Abbreviations: AP: autophagosome; AUC: area under the curve; BafA1: bafilomycin A1; COVID-19: coronavirus disease-2019; HCQ: hydroxychloroquine; RAP: rapamycin; ROC: receiver operating characteristic; SARS-CoV-2: severe acute respiratory syndrome coronavirus 2; TLR: toll like receptor; TNF/TNF-α: tumor necrosis factor

SARS-CoV-2 susceptibility and COVID-19 disease severity are associated with genetic variants affecting gene expression in a variety of tissues

Variability in SARS-CoV-2 susceptibility and COVID-19 disease severity between individuals is partly due to genetic factors. Here, we identify 4 genomic loci with suggestive associations for SARS-CoV-2 susceptibility and 19 for COVID-19 disease severity. Four of these 23 loci likely have an ethnicity-specific component. Genome-wide association study (GWAS) signals in 11 loci colocalize with expression quantitative trait loci (eQTLs) associated with the expression of 20 genes in 62 tissues/cell types (range: 1:43 tissues/gene), including lung, brain, heart, muscle, and skin as well as the digestive system and immune system. We perform genetic fine mapping to compute 99% credible SNP sets, which identify 10 GWAS loci that have eight or fewer SNPs in the credible set, including three loci with one single likely causal SNP. Our study suggests that the diverse symptoms and disease severity of COVID-19 observed between individuals is associated with variants across the genome, affecting gene expression levels in a wide variety of tissue types

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication