Warfarin pretreatment reduces cell death and MMP-9 activity in experimental intracerebral hemorrhage

Role of GDF-15, YKL-40 and MMP 9 in patients with end-stage kidney disease: focus on sex-specific associations with vascular outcomes and all-cause mortality

BACKGROUND

Sex differences are underappreciated in the current understanding of cardiovascular disease (CVD) in association with chronic kidney disease (CKD). A hallmark of CKD is vascular aging that is characterised, amongst others, by; systemic inflammation, microbiota disbalance, oxidative stress, and vascular calcification-features linked to atherosclerosis/arteriosclerosis development. Thus, it is the necessary to introduce novel biomarkers related to athero-/arteriosclerotic damage for better assessment of vascular ageing in patients CKD. However, little is known about the relationship between uraemia and novel CVD biomarkers, such as growth differentiation factor-15 (GDF-15), cartilage glycoprotein-39 (YKL-40) and matrix metalloproteinase-9 (MMP-9). Therefore, we hypothesise that there are sex-specific relationships between GDF-15, YKL-40, MMP-9 levels in end-stage kidney disease (ESKD) patients in relation to gut microbiota, vascular calcification, inflammation, comorbidities, and all-cause mortality.

METHODS

ESKD patients, males (n = 151) and females (n = 79), not receiving renal replacement therapy were selected from two ongoing prospective ESKD cohorts. GDF-15, YKL-40 and MMP9 were analysed using enzyme-linked immunosorbent assay kits. Biomarker levels were analysed in the context of gut microbiota-derived trimethylamine N-oxide (TMAO), vascular calcification, inflammatory response, oxidative stress, comorbidities, and all-cause mortality.

RESULTS

Increased GDF-15 correlated with higher TMAO in females only, and with higher coronary artery calcification and IL-6. In females, diabetes was associated with elevated GDF-15 and MMP-9, whilst males with diabetes only had elevated GDF-15. No associations were found between biomarkers and CVD comorbidity. Deceased males and females had higher GDF-15 concentrations (p = 0.01 and p < 0.001, respectively), meanwhile only YKL-40 was increased in deceased males (p = 0.02).

CONCLUSIONS

In conclusion, in males GDF-15 and YKL-40 were related to vascular calcification, inflammation, and oxidative stress, whilst in females GDF-15 was related to TMAO. Increased levels of YKL-40 and GDF-15 in males, and only GDF-15 in females, were associated with all-cause mortality. Our findings suggest that sex-specific associations of novel CVD biomarkers have a potential to affect development of cardiovascular complications in patients with ESKD.

In Silico Analysis to Identify Molecular Targets for Chemicals of Concern: The Case Study of Flocoumafen, an Anticoagulant Pesticide

Rodenticides are pesticides used worldwide, with little information available regarding health consequences in wildlife and humans. The aim of the present study was to use virtual screening to identify potential targets for flocoumafen, a superwarfarin rodenticide. Blind docking of more than 841 human proteins was carried out employing AutoDock Vina. The strength of the ligand interaction with the proteins was quantified based on the binding affinity score (kcal/mol). Results indicate that flocoumafen could be a promiscuous ligand for diversity of cellular protein targets. The best complexes were obtained for prostaglandin F synthase (-14.2 kcal/mol) and serum albumin (-14.0 kcal/mol) followed by glucocorticoid receptor 2, matrix metalloproteinase-9, nuclear receptor ROR-alpha, and activin receptor type-1, all with values equal or better than -13.5 kcal/mol. Docking method validation based on the root-mean-square deviation showed that flocoumafen had good capability to predict corresponding co-crystallized poses; and molecular dynamics simulations suggested the complex with greater binding affinity was thermodynamically stable. Protein-protein interaction networks built with main protein targets revealed that protein kinase B (AKT1), ribosomal protein S6 kinase B1 (RPS6KB1), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), retinoid X receptor alpha (RXRA), and protein phosphatase 2 catalytic subunit alpha (PPP2CA) were major hub proteins, whereas the gene ontology analysis reported that cellular response to endogenous stimulus, protein binding, and the TOR complex were the biological processes, molecular function, and cell component enrichments, respectively. These results should motivate more ecotoxicity testing for flocoumafen and other superwarfarins, as well as precautionary legislation to minimize exposure to these highly toxic chemicals. Environ Toxicol Chem 2021;40:2034-2043. © 2021 SETAC.

Inhibition of NOX4/ROS Suppresses Neuronal and Blood-Brain Barrier Injury by Attenuating Oxidative Stress After Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a common and severe neurological disorder that can effectively induce oxidative stress responses. NADPH oxidase 4 (NOX4) is a member of the NOX family of oxidases. It is expressed in the brain normally and involved in cell signal transduction and the removal of harmful substances. In some pathological conditions, it mediates inflammation and the aging of cells. However, few studies have focused on whether NOX4 is involved in brain injury caused by ICH. Therefore, this study aimed to clarify the role of NOX4 in the pathological process that occurs after ICH and the potential mechanism underlying its role. A rat model of ICH was established by the injection of collagenase type IV, and the expression of NOX4 was then determined. Further, siRNA-mediated protein expression knockdown technology was used for NOX4 knockdown, and western immunoblotting, immunohistochemistry, immunofluorescence, enzyme-linked immunosorbent assay (ELISA), and other molecular biological techniques were performed to assess the effects of NOX4 knockdown. Neurobiological scoring, brain water content determination, and other brain injury detection methods were also performed to assess the role of NOX4 following ICH. We found that the expression of NOX4 increased in the brains of rats after ICH, and that it was mainly expressed in neurons, astrocytes, vascular endothelial cells and microglia. Following NOX4 knockdown, the level of oxidative stress in the brain decreased considerably, the neurobehavioral scores improved, the levels of neuronal apoptosis reduced markedly, and the impairment of blood-brain barrier function was significantly ameliorated in rats with ICH. In conclusion, this study suggests that NOX4 expression is upregulated after ICH, which may cause an imbalance in the oxidative stress of relevant cells in the brain, leading to subsequent apoptosis of neurons and damage to the blood-brain barrier due to secondary brain injury following ICH.

Hematoma Expansion Following Intracerebral Hemorrhage: Mechanisms Targeting the Coagulation Cascade and Platelet Activation

Hematoma expansion (HE), defined as a greater than 33% increase in intracerebral hemorrhage (ICH) volume within the first 24 hours, results in significant neurological deficits, and enhancement of ICH-induced primary and secondary brain injury. An escalation in the use of oral anticoagulants has led to a surge in the incidences of oral anticoagulation-associated ICH (OAT-ICH), which has been associated with a greater risk for HE and worse functional outcomes following ICH. The oral anticoagulants in use include vitamin K antagonists, and direct thrombin and factor Xa inhibitors. Fibrinolytic agents are also frequently administered. These all act via differing mechanisms and thus have varying degrees of impact on HE and ICH outcome. Additionally, antiplatelet medications have also been increasingly prescribed, and result in increased bleeding risks and worse outcomes after ICH. Aspirin, thienopyridines, and GPIIb/IIIa receptor blockers are some of the most common agents in use clinically, and also have different effects on ICH and hemorrhage growth, based on their mechanisms of action. Recent studies have found that reduced platelet activity may be more effective in predicting ICH risk, hemorrhage expansion, and outcomes, than antiplatelet agents, and activating platelets may thus be a novel target for ICH therapy. This review explores how dysfunctions or alterations in the coagulation and platelet cascades can lead to, and/or exacerbate, hematoma expansion following intracerebral hemorrhage, and describe the mechanisms behind these effects and the drugs that induce them. We also discuss potential future therapy aimed at increasing platelet activity after ICH.

A composite neurobehavioral test to evaluate acute functional deficits after cerebellar haemorrhage in rats

Cerebellar haemorrhage accounts for 5-10% of all intracerebral haemorrhages and leads to severe, long-lasting functional deficits. Currently, there is limited research on this stroke subtype, which may be due to the lack of a suitable composite neuroscoring system specific for cerebellar injury in rodents. The purpose of this study is to develop a comprehensive composite neuroscore test for cerebellar injury using a rat model of cerebellar haemorrhage. Sixty male Sprague-Dawley rats were subjected to either sham surgery or cerebellar haemorrhage. Twenty-four hours post-injury, neurological behaviour was evaluated using 17 cost-effective and easy-to-perform tests, and a composite neuroscore was developed. The composite neuroscore was then used to assess functional recovery over seven days after cerebellar haemorrhage. Differences in the composite neuroscore deficits for the mild and moderate cerebellar haemorrhage models were observed for up to five days post-ictus. Until now, a composite neuroscore for cerebellar injury was not available for rodent studies. Herein, using mild and moderate cerebellar haemorrhage rat models a composite neuroscore for cerebellar injury was developed and used to assess functional deficits after cerebellar haemorrhage. This composite neuroscore may also be useful for other cerebellar injury models.

Melatonin Alleviates Intracerebral Hemorrhage-Induced Secondary Brain Injury in Rats via Suppressing Apoptosis, Inflammation, Oxidative Stress, DNA Damage, and Mitochondria Injury

Intracerebral hemorrhage (ICH) is a cerebrovascular disease with high mortality and morbidity, and the effective treatment is still lacking. We designed this study to investigate the therapeutic effects and mechanisms of melatonin on the secondary brain injury (SBI) after ICH. An in vivo ICH model was induced via autologous whole blood injection into the right basal ganglia in Sprague-Dawley (SD) rats. Primary rat cortical neurons were treated with oxygen hemoglobin (OxyHb) as an in vitro ICH model. The results of the in vivo study showed that melatonin alleviated severe brain edema and behavior disorders induced by ICH. Indicators of blood-brain barrier (BBB) integrity, DNA damage, inflammation, oxidative stress, apoptosis, and mitochondria damage showed a significant increase after ICH, while melatonin reduced their levels. Meanwhile, melatonin promoted further increasing of expression levels of antioxidant indicators induced by ICH. Microscopically, TUNEL and Nissl staining showed that melatonin reduced the numbers of ICH-induced apoptotic cells. Inflammation and DNA damage indicators exhibited an identical pattern compared to those above. Additionally, the in vitro study demonstrated that melatonin reduced the apoptotic neurons induced by OxyHb and protected the mitochondrial membrane potential. Collectively, our investigation showed that melatonin ameliorated ICH-induced SBI by impacting apoptosis, inflammation, oxidative stress, DNA damage, brain edema, and BBB damage and reducing mitochondrial membrane permeability transition pore opening, and melatonin may be a potential therapeutic agent of ICH.

GSK-3β Inhibition Induced Neuroprotection, Regeneration, and Functional Recovery After Intracerebral Hemorrhagic Stroke

Hemorrhagic stroke is a devastating disease that lacks effective therapies. In the present investigation, we tested 6-bromoindirubin-3'-oxime (BIO) as a selective glycogen synthase kinase-3β (GSK-3β) inhibitor in a mouse model of intracerebral hemorrhage (ICH). ICH was induced by injection of collagenase IV into the striatum of 8- to 10-week-old C57BL/6 mice. BIO (8 μg/kg, IP) was administered following either an acute delivery (0-2 h delay) or a prolonged regimen (every 48 h starting at 3 days post-ICH). At 2 days post-ICH, the acute BIO treatment significantly reduced the hematoma volume. In the perihematoma regions, BIO administration blocked GSK-3β phosphorylation/activation, increased Bcl-2 and β-catenin levels, and significantly increased viability of neurons and other cell types. The prolonged BIO regimen maintained a higher level of β-catenin, upregulated VEGF and BDNF, and promoted neurogenesis and angiogenesis in peri-injury zones at 14 days after ICH. The BIO treatment also promoted proliferation of neural stem cells (NSCs) and migration of nascent DCX+ neuroblasts from the subventricular zone (SVZ) to the lesioned cortex. BIO improved functional outcomes on both the neurological severity score and rotarod tests. The findings of this study corroborate the neuroprotective and regenerative effects of BIO and suggest that the Wnt/GSK-3β/β-catenin pathway may be explored for the treatment of acute or chronic ICH.

[Direct oral anticoagulants and acute stroke : Insights into translational research studies]

In recent years a considerable number of translational research studies on intracerebral hemorrhage and ischemic stroke have been published, which are characterized by a particular proximity to practical clinical questions. Animal research has provided insights into the pathophysiological processes and therapy effects, which have so far only been insufficiently investigated in clinical studies. This includes the effectiveness of a rapid reversal of anticoagulation in cases of anticoagulation-associated intracerebral hemorrhage and the safety of thrombolytic treatment in ischemic stroke occurring during treatment with anticoagulants. With the approval of the direct oral anticoagulants these problems have become of particular contemporary relevance. Of course, results from experimental translational studies on stroke cannot be directly translated into clinical routine. Nevertheless, these investigations help to understand the underlying processes and mechanisms and provide proof of concept data for new treatment strategies. This review summarizes the most relevant results in this field of research with a particular focus on practical clinical questions.

Galanin Protects from Caspase-8/12-initiated Neuronal Apoptosis in the Ischemic Mouse Brain via GalR1

Galanin (GAL) plays key role in many pathophysiological processes, but its role in ischemic stroke remains unclear. Here, the models of 1 h middle cerebral artery occlusion (MCAO)/1-7 d reperfusion (R)-induced ischemic stroke and in vitro cell ischemia of 1 h oxygen-glucose deprivation (OGD)/24 h reoxygenation in primary cultured cortical neurons were used to explore GAL’s effects and its underlying mechanisms. The results showed significant increases of GAL protein levels in the peri-infarct region (P) and infarct core (I) within 48 h R of MCAO mice (p<0.001). The RT-qPCR results also demonstrated significant increases of GAL mRNA during 24-48 h R (p<0.001), and GAL receptors GalR1-2 (but not 3) mRNA levels in the P region at 24 h R of MCAO mice (p<0.001). Furthermore, the significant decrease of infarct volume (p<0.05) and improved neurological outcome (p<0.001-0.05) were observed in MCAO mice following 1 h pre- or 6 h post-treatment of GAL during 1-7 d reperfusion. GalR1 was confirmed as the receptor responsible for GAL-induced neuroprotection by using GalR2/3 agonist AR-M1896 and Lentivirus-based RNAi knockdown of GalR1. GAL treatment inhibited Caspase-3 activation through the upstream initiators Capsases-8/-12 (not Caspase-9) in both P region and OGD-treated cortical neurons. Meanwhile, GAL’s neuroprotective effect was not observed in cortical neurons from conventional protein kinase C (cPKC) γ knockout mice. These results suggested that exogenous GAL protects the brain from ischemic injury by inhibiting Capsase-8/12-initiated apoptosis, possibly mediated by GalR1 via the cPKCγ signaling pathway.

Simvastatin Promotes Hematoma Absorption and Reduces Hydrocephalus Following Intraventricular Hemorrhage in Part by Upregulating CD36

We previously found that hematoma worsens hydrocephalus after intraventricular hemorrhage (IVH) via increasing iron deposition and aggravating ependymal cilia injury; therefore, promoting hematoma absorption may be a promising strategy for IVH. Recently, some investigations imply that simvastatin has the ability of accelerating hematoma absorption. Thus, this study was designed to examine the efficacy of simvastatin for IVH in rats. Intracerebral hemorrhage with ventricular extension was induced in adult male Sprague-Dawley rats after autologous blood injection. Simvastatin or vehicle was administered orally at 1 day after IVH and then daily for 1 week. MRI studies were performed to measure the volumes of intracranial hematoma and lateral ventricle at days 1, 3, 7, 14, and 28 after IVH. Motor and neurocognitive functions were assessed at days 1 to 7 and 23 to 28, respectively. Iron deposition, iron-related protein expression, ependymal damage, and histology were detected at day 28. Expression of CD36 scavenger receptor (facilitating phagocytosis) was examined at day 3 after IVH using western blotting and immunofluorescence. Simvastatin significantly increased hematoma absorption ratio, reduced ventricular volume, and attenuated neurological dysfunction post-IVH. In addition, less iron accumulation and more cilia survival was observed in the simvastatin group when compared with the control. What's more, higher expression of CD36 was detected around the hematoma after simvastatin administration. Simvastatin significantly enhanced brain hematoma absorption, alleviated hydrocephalus, and improved neurological recovery after experimental IVH, which may in part by upregulating CD36 expression. Our data suggest that early simvastatin use may be a novel therapy for IVH patients.

Anti-oxidative aspect of inhaled anesthetic gases against acute brain injury

Acute brain injury is a critical and emergent condition in clinical settings, which needs to be addressed urgently. Commonly acute brain injuries include traumatic brain injury, ischemic and hemorrhagic strokes. Oxidative stress is a key contributor to the subsequent injuries and impedes the reparative process after acute brain injury; therefore, facilitating an anti-oxidative approach is important in the care of those diseases. Readiness to deliver and permeability to blood brain barrier are essential for the use of this purpose. Inhaled anesthetic gases are a group of such agents. In this article, we discuss the anti-oxidative roles of anesthetic gases against acute brain injury.

Molecular hydrogen: a therapeutic antioxidant and beyond

Molecular hydrogen (H₂) medicine research has flourished since a landmark publication in Nature Medicine that revealed the antioxidant and cytoprotective effects of hydrogen gas in a focal stroke model. Emerging evidence has consistently demonstrated that molecular hydrogen is a promising therapeutic option for a variety of diseases and the underlying comprehensive mechanisms is beyond pure hydroxyl radicals scavenging. The non-toxicity at high concentrations and rapid cellular diffusion features of molecular hydrogen ensure the feasibility and readiness of its clinical translation to human patients.

Neuroprotective effect of hyperbaric oxygen therapy in a juvenile rat model of repetitive mild traumatic brain injury

Repetitive mild traumatic brain injury (rmTBI) is an important medical concern for adolescent athletes that can lead to long-term disabilities. Multiple mild injuries may exacerbate tissue damage resulting in cumulative brain injury and poor functional recovery. In the present study, we investigated the increased brain vulnerability to rmTBI and the effect of hyperbaric oxygen treatment using a juvenile rat model of rmTBI. Two episodes of mild cortical controlled impact (3 days apart) were induced in juvenile rats. Hyperbaric oxygen (HBO) was applied 1 hour/day × 3 days at 2 atmosphere absolute consecutively, starting at 1 day after initial mild traumatic brain injury (mTBI). Neuropathology was assessed by multi-modal magnetic resonance imaging (MRI) and tissue immunohistochemistry. After repetitive mTBI, there were increases in T2-weighted imaging-defined cortical lesions and susceptibility weighted imaging-defined cortical microhemorrhages, correlated with brain tissue gliosis at the site of impact. HBO treatment significantly decreased the MRI-identified abnormalities and tissue histopathology. Our findings suggest that HBO treatment improves the cumulative tissue damage in juvenile brain following rmTBI. Such therapy regimens could be considered in adolescent athletes at the risk of repeated concussions exposures.

Intracerebral Hemorrhage: Perihemorrhagic Edema and Secondary Hematoma Expansion: From Bench Work to Ongoing Controversies

Intracerebral hemorrhage (ICH) is a medical emergency, which often leads to severe disability and death. ICH-related poor outcomes are due to primary injury causing structural damage and mass effect and secondary injury in the perihemorrhagic region over several days to weeks. Secondary injury after ICH can be due to hematoma expansion (HE) or a consequence of repair pathway along the continuum of neuroinflammation, neuronal death, and perihemorrhagic edema (PHE). This review article is focused on PHE and HE and will cover the animal studies, related human studies, and clinical trials relating to these mechanisms of secondary brain injury in ICH patients.

The production of high dose hydrogen gas by the AMS-H-01 for treatment of disease

Hydrogen gas is a new and promising treatment option for a variety of diseases including stroke. Here, we introduce the AMS-H-01, a medically approved machine capable of safely producing ~66% hydrogen gas. Furthermore, we propose the significance of this machine in the future of hydrogen gas research.

Treatment with FTY720 has no beneficial effects on short-term outcome in an experimental model of intracerebral hemorrhage

BACKGROUND

No evidence-based therapy is available for patients with acute intracerebral hemorrhage (ICH). In view of the profound inflammatory reaction in the perilesional tissue, we investigated in a well-characterized experimental model whether the administration of the immunomodulator fingolimod (FTY720) is neuroprotective in acute ICH.

METHODS

ICH was induced by means of a stereotactic intrastriatal injection of collagenase type VII-S. FTY720 (1 mg/kg) was administered intraperitoneally 1 h after ICH induction. Hematoma volume was assessed spectrophotometrically at 24 h after ICH induction. The following endpoints were determined at 24 and 72 h, respectively: mortality rate and neurologic outcomes, edema formation, and MMP-9 activity.

RESULTS

Twenty-four hour after ICH induction, hematoma volume was not statistically different between groups. No difference was found in mortality and neurologic outcomes at 24 and 72 h between FTY720 treated mice and controls. Edema formation was present in both groups on the ipsilateral side with no statistical difference between groups at both time points. No difference was found in MMP-9 levels after 24 and 72 h between groups.

CONCLUSIONS

Our results suggest that FTY720 has no beneficial effects in the acute phase of experimental ICH.

Fucoidan from Fucus vesiculosus Fails to Improve Outcomes Following Intracerebral Hemorrhage in Mice

Intracerebral hemorrhage (ICH) is the most fatal stroke subtype, with no effective therapies. Hematoma expansion and inflammation play major roles in the pathophysiology of ICH, contributing to primary and secondary brain injury, respectively. Fucoidan, a polysaccharide from the brown seaweed Fucus vesiculosus, has been reported to activate a platelet receptor that may function in limiting bleeding, and to exhibit anti-inflammatory effects. As such, the aim of the present study was to examine the effects of fucoidan on hemorrhaging and neurological outcomes after ICH. Male CD-1 mice were subjected to experimental ICH by infusion of bacterial collagenase. Animals were randomly divided into the following groups: sham, ICH + vehicle, ICH + 25 mg/kg fucoidan, ICH + 75 mg/kg fucoidan, and ICH + 100 mg/kg fucoidan. Brain water content, neurobehavioral outcomes, and hemoglobin content were evaluated at 24 h post ICH. Our findings show that fucoidan failed to attenuate the ICH-induced increase in BWC. The neurological deficits that result from ICH also did not differ in the treatment groups at all three doses. Finally, we found that fucoidan had no effect on the hemoglobin content after ICH. We postulate that fucoidan treatment did not improve the measured outcomes after ICH because we used crude fucoidan, which has a high molecular weight, in our study. High-molecular-weight fucoidans are reported to have less therapeutic potential than low molecular weight fucoidans. They have been shown to exhibit anti-coagulant and pro-apoptotic properties, which seem to outweigh their anti-inflammatory and potential procoagulant abilities. We propose that using a low-molecular-weight fucoidan, or fractionating the crude polysaccharide, may be effective in treating ICH. Future studies are needed to confirm this.

Exsanguination Postconditioning of ICH (EPIC-H) Using the Lancet for Brain Bleed in Rodents, Preliminary Study

Cerebral iron overload contributes to free-radical damage and secondary brain injury following intracerebral hemorrhage (ICH). Phlebotomy most effectively removes iron from the human body, compared with any pharmacological agent (e.g., chelator), and does not impact mean arterial blood pressure. For centuries, this ancient method was a treatment for stroke. This is the first controlled scientific evaluation of this approach after ICH. Femoral catheterization occurred at 30 min following collagenase infusion. Three different exsanguination volumes were tested: 1, 2, 3 ml (approximately 5-15 % (normotensive) loss of total blood volume; or 3.33-10 ml/kg) compared with ICH and sham controls. Brain water content, hemorrhage size, and neuroscore were measured 24 h later. Preliminary analysis of the data demonstrated that therapeutic phlebotomy occurring shortly after ICH in adult rats significantly decreased brain edema and hemorrhagic size at 1 day after the brain injury. However, the neuroscore was unchanged compared with untreated animals. Therefore, exsanguination therapy after ICH using the traditional phlebotomy approach may eventually ameliorate early brain injury (hemorrhage and edema) in further human studies, despite equivocal changes in the short-term neurological functional ability. In meantime, translational studies must further delineate the involvement of specific neuroprotective molecules, sympathetic responses, hemodynamic-vasoactive mediators, or neuroendocrine factors involved in this apparent postconditioning approach following ICH in rodents.

Curcumin accelerates reendothelialization and ameliorates intimal hyperplasia in balloon-injured rat carotid artery via the upregulation of endothelial cell autophagy

Delayed reendothelialization and intimal hyperplasia (IH) contribute to the failure of vascular interventions. Curcumin (Cur) has been used for various types of diseases with antioxidant, antiproliferative and anti-inflammatory effects. However, investigations involving the application of Cur in inhibiting IH are limited. The aim of the present study was to evaluate the potential therapeutic effects of Cur and its underlying mechanisms on a rat model of carotid artery (CA) intimal injury. In vitro, an endothelial cell (EC) migration assay was conducted using cultured primary human umbilical vein endothelial cells (HUVECs) that were exposed to Cur. In vivo, CA angioplasty injury was used to generate a rat model of intimal injury. CAs were collected at 3 days, and 1 and 4 weeks after injury, respectively, for western blot analysis and double-immunofluorescence analyses, terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling staining, oxidative stress indicator analysis and hematoxylin and eosin staining of the neointima. In vivo, Cur significantly enhanced the migration and healing of HUVECs and simultaneously promoted microtubule-associated protein light chain 3-II (LC3-II) expression when HUVECs were subjected to an artificial scratch. In vitro, endangium from the Cur-treated rats exhibited a significantly reduced number of apoptotic ECs and oxidative stress level compared to that of the sham group. In addition, Cur treatment markedly improved quantification of the LC3-II concomitant with the downregulation of p62 in the injured CA. At 1 week following injury, sizable neointimal lesions had developed, although prominent intima thickening was not observed. At 4 weeks, apparent hemadostenosis occurred resulting from the exorbitance IH. Cur treatment markedly reduced the thickness of the neointimal lesion. It is noteworthy that high-dose Cur may have exerted more significant effects than low-dose Cur. Cur can potentially become a therapeutic drug for angiostenosis by imparting a protective effect that accelerates reendothelialization and ameliorates IH and was mediated by its pro-autophagic effect.

Dimethyl fumarate confers neuroprotection by casein kinase 2 phosphorylation of Nrf2 in murine intracerebral hemorrhage

BACKGROUND AND PURPOSE

Edema formation, inflammation and increased blood-brain barrier permeability contribute to poor outcomes after intracerebral hemorrhage (ICH). This study examined the therapeutic effect of dimethyl fumarate (DMF), a fumaric acid ester that activates nuclear factor erythroid-2 related factor 2 (Nrf2) and Nrf2 heterodimerization effector protein musculo-aponeurotic fibrosarcoma-G (MAFG) in a murine ICH model.

METHODS

Male CD-1 mice (n=176) were subjected to intrastriatal infusion of bacterial collagenase (n=126), autologous blood (n=18) or sham surgery (n=32). Four (4) animals not subjected to ICH (naive) were also included in the study. After ICH, animals either received vehicle, dimethyl fumarate (10 mg or 100 mg/kg) or casein kinase 2 inhibitor (E)-3-(2,3,4,5-tetrabromophenyl)acrylic acid (TBCA). Thirty-two mice also received scrambled siRNA or MAFG siRNA 24h before ICH. Brain water content and neurological function were evaluated.

RESULTS

Dimethyl fumarate reduced Evans blue dye extravasation, decreased brain water content, and improved neurological deficits at 24 and 72 h after ICH. Casein kinase 2 inhibitor TBCA and MAFG siRNA prevented the effect of dimethyl fumarate on brain edema and neurological function. After ICH, ICAM-1 levels increased and casein kinase 2 levels decreased. Dimethyl fumarate reduced ICAM-1 but enhanced casein kinase 2 levels. Again, casein kinase 2 inhibitor TBCA and MAFG siRNA abolished the effect of dimethyl fumarate on ICAM-1 and casein kinase 2. Dimethyl fumarate preserved pNrf2 and MAFG expression in the nuclear lysate after ICH and the effect of dimethyl fumarate was abolished by casein kinase 2 inhibitor TBCA and MAFG siRNA. Dimethyl fumarate reduced microglia activation in peri-hematoma areas after ICH. The protective effect of dimethyl fumarate on brain edema and neurological function was also observed in a blood injection mouse model.

CONCLUSION

Dimethyl fumarate ameliorated inflammation, reduced blood-brain barrier permeability, and improved neurological outcomes by casein kinase 2 and Nrf2 signaling pathways after experimental ICH in mice.