Elevated intracranial pressure after head trauma can be suppressed by antisecretory factor-a pilot study

Antisecretory factor as add-on treatment for newly diagnosed glioblastoma, IDH wildtype: study protocol for a randomized double-blind placebo-controlled trial

BACKGROUND

Glioblastoma, IDH wildtype is the most common primary malignant brain tumor in adults. Despite best available treatment, prognosis remains poor. Current standard therapy consists of surgical tumor removal followed by radiotherapy and chemotherapy with the alkylating agent temozolomide. Antisecretory factor (AF), an endogenous protein, may potentiate the effect of temozolomide and alleviate cerebral edema. Salovum® is an egg-yolk powder enriched for AF and is classified as a medical food in the European Union. Salovum® has shown preliminary clinical effect on glioblastoma in a recent pilot study. Here, we aim to assess if add-on Salovum® to temozolomide therapy can improve outcomes in patients with newly diagnosed glioblastoma.

METHODS

This is a multi-center, double-blinded, randomized, placebo-controlled phase II-III clinical trial to investigate superiority of Salovum® over placebo as add-on treatment for glioblastoma during concomitant and adjuvant temozolomide therapy. Patients with newly diagnosed glioblastoma that are planned for temozolomide treatment are screened for eligibility and randomized to receive Salovum® (n = 150) or placebo (n = 150). An interim analysis will be performed after 80 included patients to guide whether to continue or terminate. Primary endpoint is 12-month overall survival. Secondary outcome is 24-month overall survival.

DISCUSSION

This study will likely produce high-grade evidence to support or reject Salovum® as add-on treatment for glioblastoma.

TRIAL REGISTRATION

ClinicalTrials.gov NCT05669820 . Registered on January 3, 2023.

Antisecretory factor for treatment of peritumoral edema in glioblastoma patients

PURPOSE

Glioblastoma (GBM) is an aggressive brain tumor often accompanied by a vasogenic peritumoral edema, which contributes to symptoms both at diagnosis and during later stages of the disease. Previous studies have suggested effectiveness of the endogenous protein, Antisecretory Factor (AF), in reducing the intracranial pressure in cytotoxic brain edema after trauma. Interestingly, AF also seems to carry antineoplastic effects in experimental GBM models. This study investigated whether AF reduces peritumoral edema in GBM patients. As a secondary aim, we assessed potential effects on tumor progression by AF.

METHODS

Fifteen newly diagnosed GBM patients were treated for 7 days preoperatively with AF in addition to standard of care (SOC) treatment with corticosteroids. The change in edema volume was assessed volumetrically using T2/FLAIR weighted MRI and compared to a control group of 10 GBM patients receiving SOC only.

RESULTS

At baseline the mean tumor volume for the entire cohort was 35.7 cm3 with a mean edema of 62.2 cm3. There was no significant difference in edema volume change between the AF treated patients, who demonstrated a mean edema reduction of 7.1cm3 (95%CI -5.4-19.6), and the controls, 11.3cm3 (95%CI -0.8-23.5), p = 0.61. No difference was observed in tumor volume change between the two groups, p = 0.79. No adverse treatment effects were noted.

CONCLUSION

Treatment with AF in addition to SOC does not seem to reduce the peritumoral edema in GBM patients. The treatment was well tolerated. The lack of edema-reducing effect may be related to the different pathophysiological properties of vasogenic and cytotoxic edema.

Antisecretory factor in severe traumatic brain injury (AFISTBI): protocol for an exploratory randomized placebo-controlled trial

BACKGROUND

Despite recent advances in neuroimaging and neurocritical care, severe traumatic brain injury (TBI) is still a major cause of severe disability and mortality, with increasing incidence worldwide. Antisecretory factor (AF), commercially available as Salovum®, has been shown to lower intracranial pressure (ICP) in experimental models of, e.g., TBI and herpes encephalitis. The aim of this study is to assess the effect of antisecretory factors in adult patients with severe TBI on ICP and inflammatory mediators in extracellular fluid and plasma.

METHODS/DESIGN

This is a single-center, randomized, placebo-controlled clinical phase 2 trial, investigating the clinical superiority of Salovum® given as a food supplement during 5 days to adults with severe TBI (Glasgow Coma Scale (GCS) < 9), admitted to the neurocritical intensive care unit (NICU) at Skane university hospital, Lund, Sweden. All patients with GCS < 9 and clinical indication for insertion of ICP-monitor and microdialysis catheter will be screened for inclusion and assigned to either the treatment group (n = 10) or placebo group (n = 10). In both groups, the primary outcome will be ICP (mean values and change from baseline during intervention), registered from high-frequency data monitoring for 5 days. Secondary outcomes will be inflammatory mediators in plasma and intracerebral microdialysis perfusate days 1, 3, and 5 during trial treatment.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04117672. Registered on September 17, 2017. Protocol version 6 from October 24, 2023.

Neuroinflammation and neurodegeneration following traumatic brain injuries

Traumatic brain injuries (TBI) commonly occur following head trauma. TBI may result in short- and long-term complications which may lead to neurodegenerative consequences, including cognitive impairment post-TBI. When investigating the neurodegeneration following TBI, studies have highlighted the role reactive astrocytes have in the neuroinflammation and degeneration process. This review showcases a variety of markers that show reactive astrocyte presence under pathological conditions, including glial fibrillary acidic protein (GFAP), Crystallin Alpha-B (CRYA-B), Complement Component 3 (C3) and S100A10. Astrocyte activation may lead to white-matter inflammation, expressed as white-matter hyperintensities. Other white-matter changes in the brain following TBI include increased cortical thickness in the white matter. This review addresses the gaps in the literature regarding post-mortem human studies focussing on reactive astrocytes, alongside the potential uses of these proteins as markers in the future studies that investigate the proportions of astrocytes in the post-TBI brain has been discussed. This research may benefit future studies that focus on the role reactive astrocytes play in the post-TBI brain and may assist clinicians in managing patients who have suffered TBI.

Mapping the effect of the antisecretory factor on GABAA receptor α1 and α6 subunits in cerebellar granule cells in vitro

The Antisecretory Factor (AF) is a protein that can reduce intestinal hypersecretion and various inflammation disorders in vivo. Discovered in many mammalian tissues and plasma, its mechanism of action remains unknown. Interestingly, its induction has been found to counteract vertigo in patients with Méniere's disease. This suggests an inherent ability to control body balance and posture, an activity that may play a role in cerebellar function. Therefore, it may be worthwhile to investigate whether this activity can inhibit neuronal cells involved in cerebellar circuitries and its potential action on enteric nervous system ganglia, which could explain its antisecretory effect in the intestine. Previously, we studied the role of AF on GABAA receptors in cerebellar granule cells, taking advantage of electrophysiology and evaluating the effects of the administration of AF-16, an AF peptide. Treatment with AF-16 increased GABAA receptor responses, especially those containing the α6 subunit. Here, we performed immunofluorescence experiments by staining α1 and α6 subunits before and after incubation with AF-16, analyzed super-resolved images comparing pre- and post-treatment maps and critically examined these experimental results with our previous electrophysiological data to shed light on the mechanisms of action of AF protein on GABAA receptor subpopulations, specifically the "fast" receptors of αn β2/3 γ2 composition that contain either the α1 or the α6 subunit. The results indicate that the α6 subunit is redistributed, with a decrease in neurites and an increase in soma. Conversely, the α1 subunit shows opposite results, with an increase in neurites and a decrease in soma.

Antisecretory Factor 16 (AF16): A Promising Avenue for the Treatment of Traumatic Brain Injury-An In Vitro Model Approach

Traumatic brain injury (TBI) is caused by an external mechanical force to the head, resulting in abnormal brain functioning and clinical manifestations. Antisecretory factor (AF16) is a potential therapeutic agent for TBI treatment due to its ability to inhibit fluid secretion and decrease inflammation, intracranial pressure, and interstitial fluid build-up, key hallmarks presented in TBI. Here, we investigated the effect of AF16 in an in vitro model of neuronal injury, as well as its impact on key components of the autophagy pathway and mitochondrial dynamics. N2Awt cells were treated with AF16, injured using a scratch assay, and analysed using confocal microscopy, correlative light and electron microscopy (CLEM), flow cytometry, and western blotting. Our results reveal that AF16 enhances autophagy activity, regulates mitochondrial dynamics, and provides protection as early as 6 h post-injury. Fluorescently labelled AF16 was observed to localise to lysosomes and the autophagy compartment, suggesting a role for autophagy and mitochondrial quality control in conferring AF16-associated neuronal protection. This study concludes that AF16 has potential as a therapeutic agent for TBI treatment through is regulation of autophagy and mitochondrial dynamics.

Antisecretory factor in breastmilk is associated with reduced incidence of sepsis in preterm infants

BACKGROUND

Antisecretory Factor (AF) is a protein present in breastmilk that regulates inflammatory processes. We aimed to investigate the level of AF in mothers' own milk (MOM) in relation to sepsis and other neonatal morbidities in preterm infants.

METHODS

Samples of breastmilk and infant plasma were collected at 1, 4, and 12 weeks after birth from 38 mothers and their 49 infants born before 30 weeks gestation. AF-compleasome in MOM was determined by a sandwich enzyme-linked immunosorbent assay (ELISA) and inflammatory markers in infant plasma by a panel of 92 inflammatory proteins. Neonatal treatments and outcomes were recorded.

RESULTS

The level of AF in MOM week 1 was lower for infants with later sepsis compared to no sepsis (p = 0.005). Corrected for nutritional intake of MOM, higher levels of AF decreased the risk for sepsis, OR 0.24. AF in MOM week 1 was negatively correlated to inflammatory proteins in infant plasma week 4, markedly IL-8, which was also associated with infant sepsis. Overall, higher AF levels in MOM was associated with fewer major morbidities of prematurity.

CONCLUSION

Mother's milk containing high levels of antisecretory factor is associated with reduced risk for sepsis and inflammation in preterm infants.

IMPACT

High level of antisecretory factor (AF) in mothers' own milk is associated with less risk for later sepsis in preterm infants. Receiving mothers' milk with low AF levels during the first week after birth is correlated with more inflammatory proteins in infant's plasma 2-4 weeks later. Human breastmilk has anti-inflammatory properties, and antisecretory factor in mothers' own milk is a component of potential importance for infants born preterm. The findings suggest that food supplementation with AF to mothers of preterm infants to increase AF-levels in breastmilk may be a means to decrease the risk of inflammatory morbidities of prematurity.

Antisecretory factor is safe to use as add-on treatment in newly diagnosed glioblastoma

PURPOSE

Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. Despite the best available treatment, prognosis remains poor. Current standard therapy consists of surgical removal of the tumor followed by radiotherapy and chemotherapy with the alkylating agent temozolomide (TMZ). Experimental studies suggest that antisecretory factor (AF), an endogenous protein with proposed antisecretory and anti-inflammatory properties, may potentiate the effect of TMZ and alleviate cerebral edema. Salovum is an egg yolk powder enriched for AF and is classified as a medical food in the European Union. In this pilot study, we evaluate the safety and feasibility of add-on Salovum in GBM patients.

METHODS

Eight patients with newly diagnosed, histologically confirmed GBM were prescribed Salovum during concomitant radiochemotherapy. Safety was determined by the number of treatment-related adverse events. Feasibility was determined by the number of patients who completed the full prescribed Salovum treatment.

RESULTS

No serious treatment-related adverse events were observed. Out of 8 included patients, 2 did not complete the full treatment. Only one of the dropouts was due to issues directly related to Salovum, which were nausea and loss of appetite. Median survival was 23 months.

CONCLUSIONS

We conclude that Salovum is safe to use as an add-on treatment for GBM. In terms of feasibility, adherence to the treatment regimen requires a determined and independent patient as the large doses prescribed may cause nausea and loss of appetite.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04116138. Registered on 04/10/2019.

Traumatic brain injury: progress and challenges in prevention, clinical care, and research

Traumatic brain injury (TBI) has the highest incidence of all common neurological disorders, and poses a substantial public health burden. TBI is increasingly documented not only as an acute condition but also as a chronic disease with long-term consequences, including an increased risk of late-onset neurodegeneration. The first Lancet Neurology Commission on TBI, published in 2017, called for a concerted effort to tackle the global health problem posed by TBI. Since then, funding agencies have supported research both in high-income countries (HICs) and in low-income and middle-income countries (LMICs). In November 2020, the World Health Assembly, the decision-making body of WHO, passed resolution WHA73.10 for global actions on epilepsy and other neurological disorders, and WHO launched the Decade for Action on Road Safety plan in 2021. New knowledge has been generated by large observational studies, including those conducted under the umbrella of the International Traumatic Brain Injury Research (InTBIR) initiative, established as a collaboration of funding agencies in 2011. InTBIR has also provided a huge stimulus to collaborative research in TBI and has facilitated participation of global partners. The return on investment has been high, but many needs of patients with TBI remain unaddressed. This update to the 2017 Commission presents advances and discusses persisting and new challenges in prevention, clinical care, and research.

In LMICs, the occurrence of TBI is driven by road traffic incidents, often involving vulnerable road users such as motorcyclists and pedestrians. In HICs, most TBI is caused by falls, particularly in older people (aged ≥65 years), who often have comorbidities. Risk factors such as frailty and alcohol misuse provide opportunities for targeted prevention actions. Little evidence exists to inform treatment of older patients, who have been commonly excluded from past clinical trials—consequently, appropriate evidence is urgently required. Although increasing age is associated with worse outcomes from TBI, age should not dictate limitations in therapy. However, patients injured by low-energy falls (who are mostly older people) are about 50% less likely to receive critical care or emergency interventions, compared with those injured by high-energy mechanisms, such as road traffic incidents.

Mild TBI, defined as a Glasgow Coma sum score of 13–15, comprises most of the TBI cases (over 90%) presenting to hospital. Around 50% of adult patients with mild TBI presenting to hospital do not recover to pre-TBI levels of health by 6 months after their injury. Fewer than 10% of patients discharged after presenting to an emergency department for TBI in Europe currently receive follow-up. Structured follow-up after mild TBI should be considered good practice, and urgent research is needed to identify which patients with mild TBI are at risk for incomplete recovery.

The selection of patients for CT is an important triage decision in mild TBI since it allows early identification of lesions that can trigger hospital admission or life-saving surgery. Current decision making for deciding on CT is inefficient, with 90–95% of scanned patients showing no intracranial injury but being subjected to radiation risks. InTBIR studies have shown that measurement of blood-based biomarkers adds value to previously proposed clinical decision rules, holding the potential to improve efficiency while reducing radiation exposure. Increased concentrations of biomarkers in the blood of patients with a normal presentation CT scan suggest structural brain damage, which is seen on MR scanning in up to 30% of patients with mild TBI. Advanced MRI, including diffusion tensor imaging and volumetric analyses, can identify additional injuries not detectable by visual inspection of standard clinical MR images. Thus, the absence of CT abnormalities does not exclude structural damage—an observation relevant to litigation procedures, to management of mild TBI, and when CT scans are insufficient to explain the severity of the clinical condition.

Although blood-based protein biomarkers have been shown to have important roles in the evaluation of TBI, most available assays are for research use only. To date, there is only one vendor of such assays with regulatory clearance in Europe and the USA with an indication to rule out the need for CT imaging for patients with suspected TBI. Regulatory clearance is provided for a combination of biomarkers, although evidence is accumulating that a single biomarker can perform as well as a combination. Additional biomarkers and more clinical-use platforms are on the horizon, but cross-platform harmonisation of results is needed. Health-care efficiency would benefit from diversity in providers.

In the intensive care setting, automated analysis of blood pressure and intracranial pressure with calculation of derived parameters can help individualise management of TBI. Interest in the identification of subgroups of patients who might benefit more from some specific therapeutic approaches than others represents a welcome shift towards precision medicine. Comparative-effectiveness research to identify best practice has delivered on expectations for providing evidence in support of best practices, both in adult and paediatric patients with TBI.

Progress has also been made in improving outcome assessment after TBI. Key instruments have been translated into up to 20 languages and linguistically validated, and are now internationally available for clinical and research use. TBI affects multiple domains of functioning, and outcomes are affected by personal characteristics and life-course events, consistent with a multifactorial bio-psycho-socio-ecological model of TBI, as presented in the US National Academies of Sciences, Engineering, and Medicine (NASEM) 2022 report. Multidimensional assessment is desirable and might be best based on measurement of global functional impairment. More work is required to develop and implement recommendations for multidimensional assessment. Prediction of outcome is relevant to patients and their families, and can facilitate the benchmarking of quality of care. InTBIR studies have identified new building blocks (eg, blood biomarkers and quantitative CT analysis) to refine existing prognostic models. Further improvement in prognostication could come from MRI, genetics, and the integration of dynamic changes in patient status after presentation.

Neurotrauma researchers traditionally seek translation of their research findings through publications, clinical guidelines, and industry collaborations. However, to effectively impact clinical care and outcome, interactions are also needed with research funders, regulators, and policy makers, and partnership with patient organisations. Such interactions are increasingly taking place, with exemplars including interactions with the All Party Parliamentary Group on Acquired Brain Injury in the UK, the production of the NASEM report in the USA, and interactions with the US Food and Drug Administration. More interactions should be encouraged, and future discussions with regulators should include debates around consent from patients with acute mental incapacity and data sharing. Data sharing is strongly advocated by funding agencies. From January 2023, the US National Institutes of Health will require upload of research data into public repositories, but the EU requires data controllers to safeguard data security and privacy regulation. The tension between open data-sharing and adherence to privacy regulation could be resolved by cross-dataset analyses on federated platforms, with the data remaining at their original safe location. Tools already exist for conventional statistical analyses on federated platforms, however federated machine learning requires further development. Support for further development of federated platforms, and neuroinformatics more generally, should be a priority.

This update to the 2017 Commission presents new insights and challenges across a range of topics around TBI: epidemiology and prevention (section 1 ); system of care (section 2 ); clinical management (section 3 ); characterisation of TBI (section 4 ); outcome assessment (section 5 ); prognosis (Section 6 ); and new directions for acquiring and implementing evidence (section 7 ). Table 1 summarises key messages from this Commission and proposes recommendations for the way forward to advance research and clinical management of TBI.

Involvement of GABAA receptors containing α6 subtypes in antisecretory factor activity on rat cerebellar granule cells studied by two-photon uncaging

The antisecretory factor (AF) is an endogenous protein that counteracts intestinal hypersecretion and various inflammation conditions in vivo. It has been detected in many mammalian tissues and plasma, but its mechanisms of action are largely unknown. To study the pharmacological action of the AF on different GABA_A receptor populations in cerebellar granule cells, we took advantage of the two‐photon uncaging method as this technique allows to stimulate the cell locally in well‐identified plasma membrane parts. We compared the electrophysiological response evoked by releasing a caged GABA compound on the soma, the axon initial segment and neurites before and after administering AF‐16, a 16 amino acids long peptide obtained from the amino‐terminal end of the AF protein. After the treatment with AF‐16, we observed peak current increases of varying magnitude depending on the neuronal region. Thus, studying the effects of furosemide and AF‐16 on the electrophysiological behaviour of cerebellar granules, we suggest that GABA_A receptors, containing the α₆ subunit, may be specifically involved in the increase of the peak current by AF, and different receptor subtype distribution may be responsible for differences in this increase on the cell.

Effect of antisecretory factor, given as a food supplement to adult patients with severe traumatic brain injury (SASAT): protocol for an exploratory randomized double blind placebo-controlled trial

Background

Traumatic brain injury (TBI) constitutes a global epidemic. Overall outcome is poor, with mortality ranging from 10 to 70% and significant long-term morbidity. Several experimental reports have claimed effect on traumatic edema, but no clinical trials have shown effect on edema or outcome. Antisecretory factor, an endogenous protein, is commercially available as Salovum®, which is classified as a medical food by the European Union and has shown effect in experimental trauma models and feasibility with signs of effect in 2 pilot case series. The aim of this study is to assess the effect of antisecretory factor in adult patients with severe traumatic brain injury as measured by 30-day mortality, treatment intensity level (TIL), and intracranial pressure (ICP).

Methods/design

This is a single-center, double-blind, randomized, placebo-controlled clinical phase 2 trial, investigating the clinical superiority of Salovum® given as a food supplement to adults with severe TBI (GCS < 9), presenting to the trauma unit at Tygerberg University Hospital, Cape Town, South Africa, that are planned for invasive ICP monitoring and neurointensive care, will be screened for eligibility, and assigned to either treatment group (n = 50) or placebo group (n = 50). In both groups, the primary outcome will be 30-day mortality, recorded via hospital charts, follow-up phone calls, and the population registry. Secondary outcomes will be treatment intensity level (TIL), scored from hospital charts, and ICP registered from hospital data monitoring.

Trial registration

ClinicalTrials.gov NCT03339505. Registered on September 17, 2017.

Protocol version 3.0 from November 13, 2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06275-z.

Upregulation of the endogenous peptide antisecretory factor enhances hippocampal long-term potentiation and promotes learning in wistar rats

Antisecretory Factor (AF) is an endogenous peptide known for its powerful antisecretory and anti-inflammatory properties. We have previously shown that AF also acts as a neuromodulator of GABAergic synaptic transmission in rat hippocampus in a way that results in disinhibition of CA1 pyramidal neurons. Disinhibition is expected to facilitate the induction of long-term potentiation (LTP), and LTP is known to play a crucial role in learning and memory acquisition. In the present study we investigated the effect of AF on LTP in CA3-CA1 synapses in rat hippocampus. In addition, endogenous AF plasma activity was upregulated by feeding the rats with specially processed cereals (SPC) and spatial learning and memory was studied in the Morris Water Maze (MWM). We found that LTP was significantly enhanced in the presence of AF, both when added exogenously in vitro as well as when upregulated endogenously by SPC-feeding. In the presence of the GABA_A-receptor antagonist picrotoxin (PTX) there was however no significant enhancement of LTP. Moreover, rats fed with SPC demonstrated enhanced spatial learning and short-term memory, compared with control animals. These results show that the disinhibition of GABAergic transmission in the hippocampus by the endogenous peptide AF enhances LTP as well as spatial learning and memory.