scholarly journals A Sphingosine-1-Phosphate Receptor Modulator Attenuated Secondary Brain Injury and Improved Neurological Functions of Mice after ICH

2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
T. Bobinger ◽  
T. Bäuerle ◽  
L. Seyler ◽  
S. v Horsten ◽  
S. Schwab ◽  
...  

Background. Stroke activates the immune system and induces brain infiltration by immune cells, aggravating brain injury. Poststroke immunomodulation via (S1P-)receptor modulation is beneficial; however, the S1P-modulator in clinical use (FTY-720) is unspecific, and undesirable side effects have been reported. Previously, we tested effects of a novel selective S1P-receptor modulator, Siponimod, on ICH-induced brain injury in acute stage of the disease. In the current study, we investigated whether protective effects of Siponimod, evaluated in a short-term study, will protect the brain of ICH animals at long term as well. Methods. 134 C57BL/6N mice were divided into sham and ICH-operated groups. Collagenase model of ICH was employed. ICH animals were divided into Siponimod treated and nontreated. Dose- and time-dependent effects of Siponimod were investigated. Contraplay between development of brain injury and the number of lymphocytes infiltrating the brain was investigated by forelimb placing, T-Maze test, brain water content calculation, MRI scanning, and immunostaining. Results. Depending on the therapeutic strategy, Siponimod attenuated the development of brain edema, decreased ICH-induced ventriculomegaly and improved neurological functions of animals after ICH. It was associated with less lymphocytes in the brain of ICH animals. Conclusion. Siponimod is able to decrease the brain injury and improves neurological functions of animals after ICH.

2008 ◽  
Vol 108 (3) ◽  
pp. 575-587 ◽  
Author(s):  
Guy Rosenthal ◽  
Diane Morabito ◽  
Mitchell Cohen ◽  
Annina Roeytenberg ◽  
Nikita Derugin ◽  
...  

Object Traumatic brain injury (TBI) often occurs as part of a multisystem trauma that may lead to hemorrhagic shock. Effective resuscitation and restoration of oxygen delivery to the brain is important in patients with TBI because hypotension and hypoxia are associated with poor outcome in head injury. We studied the effects of hemoglobin-based oxygen-carrying (HBOC)–201 solution compared with lactated Ringer (LR) solution in a large animal model of brain injury and hemorrhage, in a blinded prospective randomized study. Methods Swine underwent brain impact injury and hemorrhage to a mean arterial pressure (MAP) of 40 mm Hg. Twenty swine were randomized to undergo resuscitation with HBOC-201 (6 ml/kg) or LR solution (12 ml/kg) and were observed for an average of 6.5 ± 0.5 hours following resuscitation. At the end of the observation period, magnetic resonance (MR) imaging was performed. Histological studies of swine brains were performed using Fluoro-Jade B, a marker of early neuronal degeneration. Results Swine resuscitated with HBOC-201 had higher MAP, higher cerebral perfusion pressure (CPP), improved base deficit, and higher brain tissue oxygen tension (PbtO2) than animals resuscitated with LR solution. No significant difference in total injury volume on T2-weighted MR imaging was observed between animals resuscitated with HBOC-201 solution (1155 ± 374 mm3) or LR solution (1246 ± 279 mm3; p = 0.55). On the side of impact injury, no significant difference in the mean number of Fluoro-Jade B–positive cells/hpf was seen between HBOC-201 solution (61.5 ± 14.7) and LR solution (48.9 ± 17.7; p = 0.13). Surprisingly, on the side opposite impact injury, a significant increase in Fluoro-Jade B–positive cells/hpf was seen in animals resuscitated with LR solution (42.8 ± 28.3) compared with those resuscitated with HBOC-201 solution (5.6 ± 8.1; p < 0.05), implying greater neuronal injury in LR-treated swine. Conclusions The improved MAP, CPP, and PbtO2 observed with HBOC-201 solution in comparison with LR solution indicates that HBOC-201 solution may be a preferable agent for small-volume resuscitation in brain-injured patients with hemorrhage. The use of HBOC-201 solution appears to decrease cellular degeneration in the brain area not directly impacted by the primary injury. Hemoglobin-based oxygen-carrying–201 solution may act by improving cerebral blood flow or increasing the oxygen-carrying capacity of blood, mitigating a second insult to the injured brain.


Author(s):  
Cheryl L. San Emeterio ◽  
Lauren A. Hymel ◽  
Thomas C. Turner ◽  
Molly E. Ogle ◽  
Emily G. Pendleton ◽  
...  

Volumetric muscle loss (VML) injuries after extremity trauma results in an important clinical challenge often associated with impaired healing, significant fibrosis, and long-term pain and functional deficits. While acute muscle injuries typically display a remarkable capacity for regeneration, critically sized VML defects present a dysregulated immune microenvironment which overwhelms innate repair mechanisms leading to chronic inflammation and pro-fibrotic signaling. In this series of studies, we developed an immunomodulatory biomaterial therapy to locally modulate the sphingosine-1-phosphate (S1P) signaling axis and resolve the persistent pro-inflammatory injury niche plaguing a critically sized VML defect. Multiparameter pseudo-temporal 2D projections of single cell cytometry data revealed subtle distinctions in the altered dynamics of specific immune subpopulations infiltrating the defect that were critical to muscle regeneration. We show that S1P receptor modulation via nanofiber delivery of Fingolimod (FTY720) was characterized by increased numbers of pro-regenerative immune subsets and coincided with an enriched pool of muscle stem cells (MuSCs) within the injured tissue. This FTY720-induced priming of the local injury milieu resulted in increased myofiber diameter and alignment across the defect space followed by enhanced revascularization and reinnervation of the injured muscle. These findings indicate that localized modulation of S1P receptor signaling via nanofiber scaffolds, which resemble the native extracellular matrix ablated upon injury, provides great potential as an immunotherapy for bolstering endogenous mechanisms of regeneration following VML injury.


Author(s):  
Jiangling Song ◽  
Jennifer A. Kim ◽  
Aaron Frank Struck ◽  
Rui Zhang ◽  
M. Brandon Westover

Secondary brain injury (SBI) is defined as new or worsening injury to the brain after an initial neurologic insult, such as hemorrhage, trauma, ischemic stroke, or infection. It is a common and potentially preventable complication following many types of primary brain injury (PBI). However, mechanistic details about how PBI leads to additional brain injury and evolves into SBI are poorly characterized. In this work, we propose a mechanistic model for the metabolic supply demand mismatch hypothesis (MSDMH) of SBI. Our model, based on the Hodgkin-Huxley model, supplemented with additional dynamics for extracellular potassium, oxygen concentration and excitotoxity, provides a high-level unified explanation for why patients with acute brain injury frequently develop SBI. We investigate how decreased oxygen, increased extracellular potassium, excitotoxicity, and seizures can induce SBI, and suggest three underlying paths for how events following PBI may lead to SBI. The proposed model also helps explain several important empirical observations, including the common association of acute brain injury with seizures, the association of seizures with tissue hypoxia and so on. In contrast to current practices which assume that ischemia plays the predominant role in SBI, our model suggests that metabolic crisis involved in SBI can also be non-ischemic. Our findings offer a more comprehensive understanding of the complex interrelationship among potassium, oxygen, excitotoxicity, seizures and SBI.


2018 ◽  
Vol 25 (3) ◽  
pp. 192-198 ◽  
Author(s):  
Brian H. Kim ◽  
Steven W. Levison

The cytokine transforming growth factor (TGF)-β1 is highly induced after encephalopathic brain injury, with data showing that it can both contribute to the pathophysiology and aid in disease resolution. In the immature brain, sustained TGFβ-signaling after injury may prolong inflammation to both exacerbate acute stage damage and perturb the normal course of development. Yet in adult encephalopathy, elevated TGFβ1 may promote a reparative state. In this review, we highlight the context-dependent actions of TGFβ-signaling in the brain during resolution of encephalopathy and focus on neuronal survival mechanisms that are affected by TGFβ1. We discuss the mechanisms that contribute to the disparate actions of TGFβ1 toward elucidating the long-term neurological and neuropsychiatric consequences that follow encephalopathic injury.


2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Xingfen Su ◽  
Handong Wang ◽  
Jinbing Zhao ◽  
Hao Pan ◽  
Lei Mao

Ethyl pyruvate (EP) has demonstrated neuroprotective effects against acute brain injury through its anti-inflammatory action. The nuclear protein high-mobility group box 1 (HMGB1) can activate inflammatory pathways when released from dying cells. This study was designed to investigate the protective effects of EP against secondary brain injury in rats after Traumatic Brain Injury (TBI). Adult male rats were randomly divided into three groups: (1) Sham + vehicle group, (2) TBI + vehicle group, and (3) TBI + EP group (n=30per group). Right parietal cortical contusion was made by using a weight-dropping TBI method. In TBI + EP group, EP was administered intraperitoneally at a dosage of 75 mg/kg at 5 min, 1 and 6 h after TBI. Brain samples were harvested at 24 h after TBI. We found that EP treatment markedly inhibited the expressions of HMGB1 and TLR4, NF-κB DNA binding activity and inflammatory mediators, such as IL-1β, TNF-αand IL-6. Also, EP treatment significantly ameliorated beam walking performance, brain edema, and cortical apoptotic cell death. These results suggest that the protective effects of EP may be mediated by the reduction of HMGB1/TLR4/NF-κB-mediated inflammatory response in the injured rat brain.


2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Teruaki Takasaki ◽  
Kanako Hagihara ◽  
Ryosuke Satoh ◽  
Reiko Sugiura

Fingolimod hydrochloride (FTY720) is a first-in-class of sphingosine-1-phosphate (S1P) receptor modulator approved to treat multiple sclerosis by its phosphorylated form (FTY720-P). Recently, a novel role of FTY720 as a potential anticancer drug has emerged. One of the anticancer mechanisms of FTY720 involves the induction of reactive oxygen species (ROS) and subsequent apoptosis, which is largely independent of its property as an S1P modulator. ROS have been considered as a double-edged sword in tumor initiation/progression. Intriguingly, prooxidant therapies have attracted much attention due to its efficacy in cancer treatment. These strategies include diverse chemotherapeutic agents and molecular targeted drugs such as sulfasalazine which inhibits the CD44v-xCT (cystine transporter) axis. In this review, we introduce our recent discoveries using a chemical genomics approach to uncover a signaling network relevant to FTY720-mediated ROS signaling and apoptosis, thereby proposing new potential targets for combination therapy as a means to enhance the antitumor efficacy of FTY720 as a ROS generator. We extend our knowledge by summarizing various measures targeting the vulnerability of cancer cells’ defense mechanisms against oxidative stress. Future directions that may lead to the best use of FTY720 and ROS-targeted strategies as a promising cancer treatment are also discussed.


Chemosphere ◽  
2017 ◽  
Vol 166 ◽  
pp. 221-229 ◽  
Author(s):  
A. Łukomska ◽  
I. Baranowska-Bosiacka ◽  
M. Budkowska ◽  
A. Pilutin ◽  
M. Tarnowski ◽  
...  

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