Search results for "Traumatic brain injury"

2019

Traumatic brain injury (TBI) is a frequent pathology and associated with poor outcome in the aged population. We recently observed accelerated cerebral inflammation in aged mice in response to TBI. Candesartan is a potent specific inhibitor of angiotensin II receptor type 1 (AT1) which limits cerebral inflammation and brain damage in juvenile animals after experimental TBI. In the present study, we show significantly lower posttraumatic AT1 mRNA levels in aged (21 months) compared to young (2 months) mice. Despite low cerebral At1 expression, pharmacologic blockade by treatment with candesartan (daily, beginning 30 minutes after experimental TBI by controlled cortical impact [CCI]) was high…

Role of Regular Physical Activity in Neuroprotection against Acute Ischemia

2020

One of the major obstacles that prevents an effective therapeutic intervention against ischemic stroke is the lack of neuroprotective agents able to reduce neuronal damage; this results in frequent evolution towards a long-term disability with limited alternatives available to aid in recovery. Nevertheless, various treatment options have shown clinical efficacy. Neurotrophins such as brain-derived neurotrophic factor (BDNF), widely produced throughout the brain, but also in distant tissues such as the muscle, have demonstrated regenerative properties with the potential to restore damaged neural tissue. Neurotrophins play a significant role in both protection and recovery of function followi…

Dimethyl fumarate treatment after traumatic brain injury prevents depletion of antioxidative brain glutathione and confers neuroprotection.

2017

Dimethyl fumarate (DMF) is an immunomodulatory compound to treat multiple sclerosis and psoriasis with neuroprotective potential. Its mechanism of action involves activation of the antioxidant pathway regulator Nuclear factor erythroid 2-related factor 2 thereby increasing synthesis of the cellular antioxidant glutathione (GSH). The objective of this study was to investigate whether post-traumatic DMF treatment is beneficial after experimental traumatic brain injury (TBI). Adult C57Bl/6 mice were subjected to controlled cortical impact followed by oral administration of DMF (80 mg/kg body weight) or vehicle at 3, 24, 48, and 72 h after the inflicted TBI. At 4 days after lesion (dal), DMF-tr…

Proinflammatory and amyloidogenic S100A9 induced by traumatic brain injury in mouse model.

2019

Traumatic brain injury (TBI) represents a significant risk factor for development of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. The S100A9-driven amyloid-neuroinflammatory cascade occurring during primary and secondary TBI events can serve as a mechanistic link between TBI and Alzheimer’s as demonstrated recently in the human brain tissues. Here by using immunohistochemistry in the controlled cortical impact TBI mouse model we have found pro-inflammatory S100A9 in the brain tissues of all mice on the first and third post-TBI days, while 70% of mice did not show any S100A9 presence on seventh post-TBI day similar to controls. This indicates that defensive mechanisms effe…

An update on intracerebral stem cell grafts.

2018

Introduction: Primary neurological disorders are notoriously debilitating and deadly, and over the past four decades stem cell therapy has emerged as a promising treatment. Translation of stem cell therapies from the bench to the clinic requires a better understanding of delivery protocols, safety profile, and efficacy in each disease. Areas covered: In this review, benefits and risks of intracerebral stem cell transplantation are presented for consideration. Milestone discoveries in stem cell applications are reviewed to examine the efficacy and safety of intracerebral stem cell transplant therapy for disorders of the central nervous system and inform design of translatable protocols for c…

Acute Cortical Transhemispheric Diaschisis after Unilateral Traumatic Brain Injury

2017

Focal neocortical brain injuries lead to functional alterations, which can spread beyond lesion-neighboring brain areas. The undamaged hemisphere and its associated disturbances after a unilateral lesion, so-called transhemispheric diaschisis, have been progressively disclosed over the last decades; they are strongly involved in the pathophysiology and, potentially, recovery of brain injuries. Understanding the temporal dynamics of these transhemispheric functional changes is crucial to decipher the role of the undamaged cortex in the processes of functional reorganization at different stages post-lesion. In this regard, little is known about the acute-subacute processes after 24-48 h in th…

Lack of NG2 exacerbates neurological outcome and modulates glial responses after traumatic brain injury

2015

Traumatic brain injury (TBI) is a major cause of death and disability. The underlying pathophysiology is characterized by secondary processes including neuronal death and gliosis. To elucidate the role of the NG2 proteoglycan we investigated the response of NG2-knockout mice (NG2-KO) to TBI. Seven days after TBI behavioral analysis, brain damage volumetry and assessment of blood brain barrier integrity demonstrated an exacerbated response of NG2-KO compared to wild-type (WT) mice. Reactive astrocytes and expression of the reactive astrocyte and neurotoxicity marker Lcn2 (Lipocalin-2) were increased in the perilesional brain tissue of NG2-KO mice. In addition, microglia/macrophages with acti…

Introducing the concept of “CSF-shift edema” in traumatic brain injury

2018

Brain edema after severe traumatic brain injury (TBI) plays an important role in the outcome and survival of injured patients. It is also one of the main targets in the therapeutic approach in the current clinical practice. To date, the pathophysiology of traumatic brain swelling is complex and, being that it is thought to be mainly cytotoxic and vasogenic in origin, not yet entirely understood. However, based on new understandings of the hydrodynamic aspects of cerebrospinal fluid (CSF), an additional mechanism of brain swelling can be considered. An increase in pressure into the subarachnoid space, secondary to traumatic subarachnoid hemorrhage, would result in a rapid shift of CSF from t…

Progranulin protects against exaggerated axonal injury and astrogliosis following traumatic brain injury

2016

In response to traumatic brain injury (TBI) microglia/macrophages and astrocytes release inflammatory mediators with dual effects on secondary brain damage progression. The neurotrophic and anti-inflammatory glycoprotein progranulin (PGRN) attenuates neuronal damage and microglia/macrophage activation in brain injury but mechanisms are still elusive. Here, we studied histopathology, neurology and gene expression of inflammatory markers in PGRN-deficient mice (Grn-/- ) 24 h and 5 days after experimental TBI. Grn-/- mice displayed increased perilesional axonal injury even though the overall brain tissue loss and neurological consequences were similar to wild-type mice. Brain inflammation was …

Depletion of regulatory T cells increases T cell brain infiltration, reactive astrogliosis, and interferon-γ gene expression in acute experimental tr…

2019

Abstract Background Traumatic brain injury (TBI) is a major cause of death and disability. T cells were shown to infiltrate the brain during the first days after injury and to exacerbate tissue damage. The objective of this study was to investigate the hitherto unresolved role of immunosuppressive, regulatory T cells (Tregs) in experimental TBI. Methods “Depletion of regulatory T cell” (DEREG) and wild type (WT) C57Bl/6 mice, treated with diphtheria toxin (DTx) to deplete Tregs or to serve as control, were subjected to the controlled cortical impact (CCI) model of TBI. Neurological and motor deficits were examined until 5 days post-injury (dpi). At the 5 dpi endpoint, (immuno-) histological…