N-Acetylcysteine and Selenium Modulate Oxidative Stress, Antioxidant Vitamin and Cytokine Values in Traumatic Brain Injury-Induced Rats

The neuroprotective effects of N-acetylcysteine in psychiatric and neurodegenerative disorders: From modulation of glutamatergic transmission to restoration of synaptic plasticity

N-acetylcysteine (NAC) is an effective pleiotropic drug with a strong safety profile. It is predominantly used as a mucolytic agent and in the treatment of paracetamol overdose. However, extensive research in the last decade has shown the prominent efficacy of NAC in many neuropsychiatric and neurodegenerative disorders. NAC acts through multiple mechanisms; primarily, it releases cysteine and modulates glutamatergic and monoaminergic transmission. Further, it restores glutathione levels, promotes oxidative balance, reverses decreased synaptic plasticity, reduces neuroinflammation and mitochondrial dysfunction, and provides neurotrophic support. Additionally, it regulates one-carbon metabolism pathways, leading to the production of key metabolites. In this review, we will be discussing in-depth mechanisms of action of NAC and its promising ability to reverse neuropathological changes, particularly cognitive deficits, and associated plasticity changes in various psychiatric and neurodegenerative diseases, including depression, bipolar disorders, schizophrenia, Alzheimer's disease, Huntington's disease, traumatic brain injury, aging. Overall, several preclinical studies and clinical trials have demonstrated the efficacy of NAC in reversing regressive plasticity, cognitive deficits, and associated changes in the brain. NAC remains among the strongest candidates with a high safety profile for managing several types of neurological disorders.

The Crucial Role of the Blood-Brain Barrier in Neurodegenerative Diseases: Mechanisms of Disruption and Therapeutic Implications

The blood-brain barrier (BBB) is a crucial structure that maintains brain homeostasis by regulating the entry of molecules and cells from the bloodstream into the central nervous system (CNS). Neurodegenerative diseases such as Alzheimer's and Parkinson's disease, as well as ischemic stroke, compromise the integrity of the BBB. This leads to increased permeability and the infiltration of harmful substances, thereby accelerating neurodegeneration. In this review, we explore the mechanisms underlying BBB disruption, including oxidative stress, neuroinflammation, vascular dysfunction, and the loss of tight junction integrity, in patients with neurodegenerative diseases. We discuss how BBB breakdown contributes to neuroinflammation, neurotoxicity, and the abnormal accumulation of pathological proteins, all of which exacerbate neuronal damage and facilitate disease progression. Furthermore, we discuss potential therapeutic strategies aimed at preserving or restoring BBB function, such as anti-inflammatory treatments, antioxidant therapies, and approaches to enhance tight junction integrity. Given the central role of the BBB in neurodegeneration, maintaining its integrity represents a promising therapeutic approach to slow or prevent the progression of neurodegenerative diseases.

N-Acetylcysteine and Probenecid Adjuvant Therapy for Traumatic Brain Injury

N-Acetylcysteine (NAC) has shown promise as a putative neurotherapeutic for traumatic brain injury (TBI). Yet, many such promising compounds have limited ability to cross the blood-brain barrier (BBB), achieve therapeutic concentrations in brain, demonstrate target engagement, among other things, that have hampered successful translation. A pharmacologic strategy for overcoming poor BBB permeability and/or efflux out of the brain of organic acid-based, small molecule therapeutics such as NAC is co-administration with a targeted or nonselective membrane transporter inhibitor. Probenecid is a classic ATP-binding cassette and solute carrier inhibitor that blocks transport of organic acids, including NAC. Accordingly, combination therapy using probenecid as an adjuvant with NAC represents a logical neurotherapeutic strategy for treatment of TBI (and other CNS diseases). We have completed a proof-of-concept pilot study using this drug combination in children with severe TBI-the Pro-NAC Trial (ClinicalTrials.gov NCT01322009). In this review, we will discuss the background and rationale for combination therapy with probenecid and NAC in TBI, providing justification for further clinical investigation.

Progress in research on the role of clinical nutrition in treating traumatic brain injury affecting the neurovascular unit

The neurovascular unit (NVU) is composed of neurons, glial cells, and blood vessels. NVU dysfunction involves the processes of neuroinflammation, and microcirculatory disturbances, as well as neuronal injury after traumatic brain injury (TBI). Traditional anti-inflammatory drugs have limited efficacy in improving the prognosis of TBI. Thus, treatments that target NVU dysfunction may provide a breakthrough. A large number of clinical studies have shown that the nutritional status of patients with TBI was closely related to their conditions and prognoses. Nutrient complexes and complementary therapies for the treatment of TBI are therefore being implemented in many preclinical studies. Importantly, the mechanism of action for this treatment may be related to repair of NVU dysfunction by ensuring adequate omega-3 fatty acids, curcumin, resveratrol, apigenin, vitamins, and minerals. These nutritional supplements hold promise for translation to clinical therapy. In addition, dietary habits also play an important role in the rehabilitation of TBI. Poor dietary habits may worsen the pathology and prognosis of TBI. Adjusting dietary habits, especially with a ketogenic diet, may improve outcomes in patients with TBI. This article discusses the impact of clinical nutrition on NVU dysfunction after TBI, focusing on nutritional complexes and dietary habits.

Oxidative stress and mitochondrial dysfunction following traumatic brain injury: From mechanistic view to targeted therapeutic opportunities

Traumatic brain injury (TBI) is one of the most prevalent causes of permanent physical and cognitive disabilities. TBI pathology results from primary insults and a multi-mechanistic biochemical process, termed as secondary brain injury. Currently, there are no pharmacological agents for definitive treatment of patients with TBI. This article is presented with the purpose of reviewing molecular mechanisms of TBI pathology, as well as potential strategies and agents against pathological pathways. In this review article, materials were obtained by searching PubMed, Scopus, Elsevier, Web of Science, and Google Scholar. This search was considered without time limitation. Evidence indicates that oxidative stress and mitochondrial dysfunction are two key mediators of the secondary injury cascade in TBI pathology. TBI-induced oxidative damage results in the structural and functional impairments of cellular and subcellular components, such as mitochondria. Impairments of mitochondrial electron transfer chain and mitochondrial membrane potential result in a vicious cycle of free radical formation and cell apoptosis. The results of some preclinical and clinical studies, evaluating mitochondria-targeted therapies, such as mitochondria-targeted antioxidants and compounds with pleiotropic effects after TBI, are promising. As a proposed strategy in recent years, mitochondria-targeted multipotential therapy is a new hope, waiting to be confirmed. Moreover, based on the available findings, biologics, such as stem cell-based therapy and transplantation of mitochondria are novel potential strategies for the treatment of TBI; however, more studies are needed to clearly confirm the safety and efficacy of these strategies.

Targeting Molecular Mediators of Ferroptosis and Oxidative Stress for Neurological Disorders

With the acceleration of population aging, nervous system diseases including Alzheimer's disease (AD), Parkinson's disease (PD), Huntington's disease (HD), anxiety, depression, stroke, and traumatic brain injury (TBI) have become a huge burden on families and society. The mechanism of neurological disorders is complex, which also lacks effective treatment, so relevant research is required to solve these problems urgently. Given that oxidative stress-induced lipid peroxidation eventually leads to ferroptosis, both oxidative stress and ferroptosis are important mechanisms causing neurological disorders, targeting mediators of oxidative stress and ferroptosis have become a hot research direction at present. Our review provides a current view of the mechanisms underlying ferroptosis and oxidative stress participate in neurological disorders, the potential application of molecular mediators targeting ferroptosis and oxidative stress in neurological disorders. The target of molecular mediators or agents of oxidative stress and ferroptosis associated with neurological disorders, such as reactive oxygen species (ROS), nuclear factor erythroid 2–related factor-antioxidant response element (Nrf2-ARE), n-acetylcysteine (NAC), Fe²⁺, NADPH, and its oxidases NOX, has been described in this article. Given that oxidative stress-induced ferroptosis plays a pivotal role in neurological disorders, further research on the mechanisms of ferroptosis caused by oxidative stress will help provide new targets for the treatment of neurological disorders.

Targeting Oxidative Stress with Antioxidant Duotherapy after Experimental Traumatic Brain Injury

We assessed the effect of antioxidant therapy using the Food and Drug Administration-approved respiratory drug N-acetylcysteine (NAC) or sulforaphane (SFN) as monotherapies or duotherapy in vitro in neuron-BV2 microglial co-cultures and validated the results in a lateral fluid-percussion model of TBI in rats. As in vitro measures, we assessed neuronal viability by microtubule-associated-protein 2 immunostaining, neuroinflammation by monitoring tumor necrosis factor (TNF) levels, and neurotoxicity by measuring nitrite levels. In vitro, duotherapy with NAC and SFN reduced nitrite levels to 40% (p < 0.001) and neuroinflammation to -29% (p < 0.001) compared with untreated culture. The treatment also improved neuronal viability up to 72% of that in a positive control (p < 0.001). The effect of NAC was negligible, however, compared with SFN. In vivo, antioxidant duotherapy slightly improved performance in the beam walking test. Interestingly, duotherapy treatment decreased the plasma interleukin-6 and TNF levels in sham-operated controls (p < 0.05). After TBI, no treatment effect on HMGB1 or plasma cytokine levels was detected. Also, no treatment effects on the composite neuroscore or cortical lesion area were detected. The robust favorable effect of duotherapy on neuroprotection, neuroinflammation, and oxidative stress in neuron-BV2 microglial co-cultures translated to modest favorable in vivo effects in a severe TBI model.

Ferroptosis and traumatic brain injury

Traumatic brain injury (TBI) is a worldwide health problem contributing to significant economic burden. TBI is difficult to treat partly due to incomplete understanding of pathophysiology. Ferroptosis is a type of iron-dependent programmed cell death which has gained increasing attention due to its possible role in TBI. Current studies have demonstrated that ferroptosis is related to the pathology of TBI, and inhibition of ferroptosis may improve long term outcomes of TBI. Therefore, clarification of the exact association between ferroptosis and traumatic brain injury is necessary and may provide new targets for treatment. This review describes (1) the ferroptosis pathways following traumatic brain injury, (2) the role of ferroptosis during the chronic phase of traumatic brain injury, and (3) potential therapies targeting the ferroptosis pathways.

Nutritional factors in sport-related concussion

BACKGROUND

Sports concussion is a major problem that affects thousands of people every year. Concussion-related neurometabolic changes are thought to underlie neurophysiological alterations and post-concussion symptoms, such as headaches and sensitivity to light and noise, disabilities of concentration and tiredness. The injury triggers a complex neurometabolic cascade involving multiple mechanisms. There are pharmaceutical treatments that target one mechanism, but specific nutrients have been found to impact several pathways, thus offering a broader approach. This has prompted intensive research into the use of nutrient supplements as a concussion prevention and treatment strategy.

METHOD

We realised a bibliographic state of art providing a contemporary clinical and preclinical studies dealing with nutritional factors in sport-related concussion.

RESULTS

Numerous supplements, including n-3 polyunsaturated fatty acids, sulfur amino acids, antioxidants and minerals, have shown promising results as aids to concussion recovery or prevention in animal studies, most of which use a fluid percussion technique to cause brain injury, and in a few human studies of severe or moderate traumatic brain injury. Current ongoing human trials can hopefully provide us with more information, in particular, on new options, i.e. probiotics, lactate or amino acids, for the use of nutritional supplements for concussed athletes.

CONCLUSION

Nutritional supplementation has emerged as a potential strategy to prevent and/or reduce the deleterious effects of sports-related concussion and subconcussive impacts.

An Overview and Therapeutic Promise of Nutraceuticals against Sports-Related Brain Injury

Sports-related traumatic brain injury (TBI) is one of the common neurological maladies experienced by athletes. Earlier the term 'punch drunk syndrome' was used in the case TBI of boxers and now this term is replaced by chronic traumatic encephalopathy (CTE). Sports-related brain injury can either be short term or long term. A common instance of brain injury encompasses subdural hematoma, concussion, cognitive dysfunction, amnesia, headache, vision issue, axonopathy, or even death if remain undiagnosed or untreated. Further, chronic TBI may lead to pathogenesis of neuroinflammation and neurodegeneration via tauopathy, formation of neurofibrillary tangles, and damage to the blood-brain barrier, microglial, and astrocyte activation. Thus, altered pathological, neurochemical, and neurometabolic attributes lead to the modulation of multiple signaling pathways and cause neurological dysfunction. Available pharmaceutical interventions are based on one drug one target hypothesis and thereby unable to cover altered multiple signaling pathways. However, in recent time's pharmacological intervention of nutrients and nutraceuticals have been explored as they exert a multifactorial mode of action and maintain over homeostasis of the body. There are various reports available showing the positive therapeutic effect of nutraceuticals in sport-related brain injury. Therefore, in the current article we have discussed the pathology, neurological consequence, sequelae, and perpetuation of sports-related brain injury. Further, we have discussed various nutraceutical supplements as well as available animal models to explore the neuroprotective effect/ upshots of these nutraceuticals in sports-related brain injury.

Serum Metabolomics Profiling of Commercially Mixed Functional Foods—Effects in Beta-Amyloid Induced Rats Measured Using 1H NMR Spectroscopy

Functional foods such as pomegranate, dates and honey were shown by various previous studies to individually have a neuroprotective effect, especially in neurodegenerative disease such as Alzheimer’s disease (AD). In this novel and original study, an ¹H NMR spectroscopy tool was used to identify the metabolic neuroprotective mechanism of commercially mixed functional foods (MFF) consisting of pomegranate, dates and honey, in rats injected with amyloid-beta 1-42 (Aβ-42). Forty-five male albino Wistar rats were randomly divided into five groups: NC (0.9% normal saline treatment + phosphate buffer solution (PBS) solution injection), Abeta (0.9% normal saline treatment + 0.2 µg/µL Aβ-42 injection), MFF (4 mL/kg MFF treatment + PBS solution injection), Abeta–MFF (4 mL/kg MFF treatment + 0.2 µg/µL Aβ-42 injection) and Abeta–NAC (150 mg/kg N-acetylcysteine + 0.2 µg/µL Aβ-42 injection). Based on the results, the MFF and NAC treatment improved the spatial memory and learning using Y-maze. In the metabolic analysis, a total of 12 metabolites were identified, for which levels changed significantly among the treatment groups. Systematic metabolic pathway analysis found that the MFF and NAC treatments provided a neuroprotective effect in Aβ-42 injected rats by improving the acid amino and energy metabolisms. Overall, this finding showed that MFF might serve as a potential neuroprotective functional food for the prevention of AD.

Ferroptosis in Acute Central Nervous System Injuries: The Future Direction?

Acute central nervous system (CNS) injuries, such as stroke, traumatic brain injury (TBI), and spinal cord injury (SCI) present a grave health care challenge worldwide due to high morbidity and mortality, as well as limited clinical therapeutic strategies. Established literature has shown that oxidative stress (OS), inflammation, excitotoxicity, and apoptosis play important roles in the pathophysiological processes of acute CNS injuries. Recently, there have been many studies on the topic of ferroptosis, a form of regulated cell death characterized by the accumulation of iron-dependent lipid peroxidation. Some studies have revealed an emerging connection between acute CNS injuries and ferroptosis. Ferroptosis, induced by the abnormal metabolism of lipids, glutathione (GSH), and iron, can accelerate acute CNS injuries. However, pharmaceutical agents, such as iron chelators, ferrostatin-1 (Fer-1), and liproxstatin-1 (Lip-1), can inhibit ferroptosis and may have neuroprotective effects after acute CNS injuries. However, the specific mechanisms underlying this connection has not yet been clearly elucidated. In this paper, we discuss the general mechanisms of ferroptosis and its role in stroke, TBI, and SCI. We also summarize ferroptosis-related drugs and highlight the potential therapeutic strategies in treating various acute CNS injuries. Additionally, this paper suggests a testable hypothesis that ferroptosis may be a novel direction for further research of acute CNS injuries by providing corresponding evidence.

Oxidative Stress-Mediated Blood-Brain Barrier (BBB) Disruption in Neurological Diseases

The blood-brain barrier (BBB), as a crucial gate of brain-blood molecular exchange, is involved in the pathogenesis of multiple neurological diseases. Oxidative stress is caused by an imbalance between the production of reactive oxygen species (ROS) and the scavenger system. Since oxidative stress plays a significant role in the production and maintenance of the BBB, the cerebrovascular system is especially vulnerable to it. The pathways that initiate BBB dysfunction include, but are not limited to, mitochondrial dysfunction, excitotoxicity, iron metabolism, cytokines, pyroptosis, and necroptosis, all converging on the generation of ROS. Interestingly, ROS also provide common triggers that directly regulate BBB damage, parameters including tight junction (TJ) modifications, transporters, matrix metalloproteinase (MMP) activation, inflammatory responses, and autophagy. We will discuss the role of oxidative stress-mediated BBB disruption in neurological diseases, such as hemorrhagic stroke, ischemic stroke (IS), Alzheimer’s disease (AD), Parkinson’s disease (PD), traumatic brain injury (TBI), amyotrophic lateral sclerosis (ALS), and cerebral small vessel disease (CSVD). This review will also discuss the latest clinical evidence of potential biomarkers and antioxidant drugs towards oxidative stress in neurological diseases. A deeper understanding of how oxidative stress damages BBB may open up more therapeutic options for the treatment of neurological diseases.

Antioxidant Therapies in Traumatic Brain Injury

Due to a multiplicity of causes provoking traumatic brain injury (TBI), TBI is a highly heterogeneous pathology, characterized by high mortality and disability rates. TBI is an acute neurodegenerative event, potentially and unpredictably evolving into sub-chronic and chronic neurodegenerative events, with transient or permanent neurologic, cognitive, and motor deficits, for which no valid standardized therapies are available. A vast body of literature demonstrates that TBI-induced oxidative/nitrosative stress is involved in the development of both acute and chronic neurodegenerative disorders. Cellular defenses against this phenomenon are largely dependent on low molecular weight antioxidants, most of which are consumed with diet or as nutraceutical supplements. A large number of studies have evaluated the efficacy of antioxidant administration to decrease TBI-associated damage in various animal TBI models and in a limited number of clinical trials. Points of weakness of preclinical studies are represented by the large variability in the TBI model adopted, in the antioxidant tested, in the timing, dosages, and routes of administration used, and in the variety of molecular and/or neurocognitive parameters evaluated. The analysis of the very few clinical studies does not allow strong conclusions to be drawn on the real effectiveness of antioxidant administration to TBI patients. Standardizing TBI models and different experimental conditions, as well as testing the efficacy of administration of a cocktail of antioxidants rather than only one, should be mandatory. According to some promising clinical results, it appears that sports-related concussion is probably the best type of TBI to test the benefits of antioxidant administration.

Characterising the brain metalloproteome in Down syndrome patients with concomitant Alzheimer's pathology

Down syndrome (DS) is a common intellectual disability, with an incidence of 1 in 700 and is caused by trisomy 21. People with DS develop Alzheimer's disease (AD)-like neuropathology by the age of 40. As metal ion dyshomeostasis (particularly zinc, iron and copper) is one of the characteristics of AD and is believed to be involved in the pathogenesis of disease, we reasoned that it may also be altered in DS. Thus, we used inductively coupled plasma mass spectrometry to examine metal levels in post-mortem brain tissue from DS individuals with concomitant AD pathology. Size exclusion-ICPMS was also utilised to characterise the metalloproteome in these cases. We report here for the first time that iron levels were higher in a number of regions in the DS brain, including the hippocampus (40%), frontal cortex (100%) and temporal cortex (34%), compared to controls. Zinc and copper were also elevated (both 29%) in the DS frontal cortex, but zinc was decreased (23%) in the DS temporal cortex. Other elements were also examined, a number of which also showed disease-specific changes. The metalloproteomic profile in the DS brain was also different to that in the controls. These data suggest that metals and metal:protein interactions are dysregulated in the DS brain which, given the known role of metals in neurodegeneration and AD, is likely to contribute to the pathogenesis of disease. Interrogation of the underlying cellular mechanisms and consequences of this failure in metal ion homeostasis, and the specific contributions of the individual DS and AD phenotypes to these changes, should be explored.

Changes in tissue gadolinium biodistribution measured in an animal model exposed to four chelating agents

PURPOSE

This study investigated the potential to reduce gadolinium levels in rodents after repetitive IV Gadodiamide administration using several chelating agents.

MATERIALS AND METHODS

The following six groups of rats were studied. Group 1: Control; Group 2: Gadodiamide only; Group 3: Meso-2,3-Dimercaptosuccinic acid (DMSA) + Gadodiamide; Group 4: N-Acetyl-L-cysteine (NAC) + Gadodiamide; Group 5: Coriandrum sativum extract + Gadodiamide; and Group 6: Deferoxamine + Gadodiamide. Brain, kidney, and blood samples were evaluated via inductively coupled plasma mass spectrometry. The brain was also evaluated histologically.

RESULTS

Kidney gadolinium levels in Groups 4 and 5 were approximately double that of Group 2 (p = 0.033 for each). There was almost no calcification in rat hippocampus for Group 4 rodents when compared with Groups 2, 3, 5 and 6.

CONCLUSION

Our preliminary study shows that excretion to the kidney has a higher propensity in NAC and Coriandrum sativum groups. It may be possible to change the distribution of gadolinium by administrating several agents. NAC may lower Gadodiamide-induced mineralization in rat hippocampus.

Selenium Nanoparticles Dispersed in Phytochemical Exert Anti-Inflammatory Activity by Modulating Catalase, GPx1, and COX-2 Gene Expression in a Rheumatoid Arthritis Rat Model

BACKGROUND Literature shows that serum selenium concentration is low in rheumatoid arthritis (RA) patients. Biochemical properties of nanoparticles (NPs) are depend in its medium dispersed. Biochemical properties could effectively alter the therapeutic potential of NPs. Phytochemicals could serve as suitable medium for dispersion of NPs. P-Coumaric acid (CA) known to have anti-inflammatory activity. MATERIAL AND METHODS In the present experiment, we investigated the anti-inflammatory effect of SeNPs dispersed in 1% CA against Complete Freund's adjuvant induced RA. Celecoxib was used as a reference drug. RESULTS Selenium NPs (SeNPs) size is maintained in 1% CA solution. We observed that supplementation with 500 μg/Kg body weight (b.w.) eNPs significantly restored the levels of thiobarbituric acid reactive substances, COX-2 activity, different antioxidant enzyme activities, and inflammatory cytokines (TNF-α, IL-1β, IL-6, and MCP-1) in RA rats. The mRNA expression of antioxidant enzymes such as MnSOD, Cu/ZnSOD, ECSOD, CAT, and GPx1 was found to be downregulated, whereas COX-2 was upregulated in RA rats; however, the mRNA expression of CAT, GPx1, and COX-2 reverted back to near normal levels in SeNPs-treated animals. CONCLUSIONS The therapeutic potential of SeNPs was confirmed through histological observation of angle joints in different experimental animals. Our results collectively suggest that SeNPs dispersed in CA can be an effective therapeutic agent for inflammatory disorders like acute gouty arthritis.

Neuroprotective effects of antioxidants in the management of neurodegenerative disorders: A literature review

It is proven that oxidative stress has a pivotal role in the process of neurodegeneration. The use of antioxidants is an attractive method to prevent the incidence of neurodegenerative diseases. We searched major databases (PubMed, Medline, and Google Scholar) using the keywords of neurodegeneration, oxidative stress, and antioxidant for both review and original studies, which have reported the various beneficial effects of antioxidants. About 70 studies were identified for this review. Among various antioxidants, nine antioxidants with the most applications in research investigations were selected and the major findings concerning their protective effects were reviewed. It is concluded that antioxidants can modify and readjust the oxidative stress in the biological milieu, elicit neuroprotective effects, and positively impact the management of neurodegenerative processes.

Neuroprotective effects of pifithrin-α against traumatic brain injury in the striatum through suppression of neuroinflammation, oxidative stress, autophagy, and apoptosis

Cortical and hippocampal neuronal damages caused by traumatic brain injury (TBI) are associated with motor and cognitive impairments; however, only little attention paid to the striatal damage. It is known that the p53 tumor-suppressor transcription factor participated in TBI-induced secondary brain damage. We investigated how the p53 inactivator pifithrin (PFT)-α affected TBI-induced striatal neuronal damage at 24 h post-injury. Sprague-Dawley rats subjected to a controlled cortical impact were used as TBI models. We observed that p53 mRNA significantly increased, whereas p53 protein expression was distributed predominantly in neurons but not in glia cells in striatum after TBI. PFT-α improved motor deficit following TBI. PFT-α suppressed TBI-induced striatal glial activation and expression of proinflammatory cytokines. PFT-α alleviated TBI-induced oxidative damage TBI induced autophagy was evidenced by increased protein expression of Beclin-1 and shift of microtubule-associated light chain (LC)3-I to LC3-II, and decreased p62. These effects were reduced by PFT-α. Post-injury PFT-α treatment reduced the number of degenerating (FJC-positive) and apoptotic neurons. Our results suggest that PFT-α may provide neuroprotective effects via p53-dependent or -independent mechanisms depending on the cell type and timing after the TBI and can possibly be developed into a novel therapy to ameliorate TBI-induced neuronal damage.

Systematic Review of Human and Animal Studies Examining the Efficacy and Safety of N-Acetylcysteine (NAC) and N-Acetylcysteine Amide (NACA) in Traumatic Brain Injury: Impact on Neurofunctional Outcome and Biomarkers of Oxidative Stress and Inflammation

Background

No new therapies for traumatic brain injury (TBI) have been officially translated into current practice. At the tissue and cellular level, both inflammatory and oxidative processes may be exacerbated post-injury and contribute to further brain damage. N-acetylcysteine (NAC) has the potential to downregulate both processes. This review focuses on the potential neuroprotective utility of NAC and N-acetylcysteine amide (NACA) post-TBI.

Methods

Medline, Embase, Cochrane Library, and ClinicalTrials.gov were searched up to July 2017. Studies that examined clinical and laboratory effects of NAC and NACA post-TBI in human and animal studies were included. Risk of bias was assessed in human and animal studies according to the design of each study (randomized or not). The primary outcome assessed was the effect of NAC/NACA treatment on functional outcome, while secondary outcomes included the impact on biomarkers of inflammation and oxidation. Due to the clinical and methodological heterogeneity observed across studies, no meta-analyses were conducted.

Results

Our analyses revealed only three human trials, including two randomized controlled trials (RCTs) and 20 animal studies conducted using standardized animal models of brain injury. The two RCTs reported improvement in the functional outcome post-NAC/NACA administration. Overall, the evidence from animal studies is more robust and demonstrated substantial improvement of cognition and psychomotor performance following NAC/NACA use. Animal studies also reported significantly more cortical sparing, reduced apoptosis, and lower levels of biomarkers of inflammation and oxidative stress. No safety concerns were reported in any of the studies included in this analysis.

Conclusion

Evidence from the animal literature demonstrates a robust association for the prophylactic application of NAC and NACA post-TBI with improved neurofunctional outcomes and downregulation of inflammatory and oxidative stress markers at the tissue level. While a growing body of scientific literature suggests putative beneficial effects of NAC/NACA treatment for TBI, the lack of well-designed and controlled clinical investigations, evaluating therapeutic outcomes, prognostic biomarkers, and safety profiles, limits definitive interpretation and recommendations for its application in humans at this time.

Post-Operative Cognitive Dysfunction: An exploration of the inflammatory hypothesis and novel therapies

Post-Operative Cognitive Dysfunction (POCD) is a highly prevalent condition with significant clinical, social and financial impacts for patients and their communities. The underlying pathophysiology is becoming increasingly understood, with the role of neuroinflammation and oxidative stress secondary to surgery and anaesthesia strongly implicated. This review aims to describe the putative mechanisms by which surgery-induced inflammation produces cognitive sequelae, with a focus on identifying potential novel therapies based upon their ability to modify these pathways.

Lack of mitochondrial ferritin aggravated neurological deficits via enhancing oxidative stress in a traumatic brain injury murine model

Oxidative stress has been strongly implicated in the pathogenesis of traumatic brain injury (TBI). Mitochondrial ferritin (Ftmt) is reported to be closely related to oxidative stress. However, whether Ftmt is involved in TBI-induced oxidative stress and neurological deficits remains unknown. In the present study, the controlled cortical impact model was established in wild-type and Ftmt knockout mice as a TBI model. The Ftmt expression, oxidative stress, neurological deficits, and brain injury were measured. We found that Ftmt expression was gradually decreased from 3 to 14 days post-TBI, while oxidative stress was gradually increased, as evidenced by reduced GSH and superoxide dismutase levels and elevated malondialdehyde and nitric oxide levels. Interestingly, the extent of reduced Ftmt expression in the brain was linearly correlated with oxidative stress. Knockout of Ftmt significantly exacerbated TBI-induced oxidative stress, intracerebral hemorrhage, brain infarction, edema, neurological severity score, memory impairment, and neurological deficits. However, all these effects in Ftmt knockout mice were markedly mitigated by pharmacological inhibition of oxidative stress using an antioxidant, N-acetylcysteine. Taken together, these results reveal an important correlation between Ftmt and oxidative stress after TBI. Ftmt deficiency aggravates TBI-induced brain injuries and neurological deficits, which at least partially through increasing oxidative stress levels. Our data suggest that Ftmt may be a promising molecular target for the treatment of TBI.

Early selenium treatment for traumatic brain injury: Does it improve survival and functional outcome?

BACKGROUND

Traumatic brain injury (TBI) is a major cause of death and debility following trauma. The initial brain tissue insult is worsened by secondary reactive responses including oxidative stress reactions, inflammatory changes and subsequent permanent neurologic deficits. Effective agents to improve functional outcome and survival following TBI are scarce. Selenium is an antioxidant which has shown to reduce oxidative stress. This study examines the effect of intravenous selenium (Selenase^®) treatment in patients with severe TBI on functional outcome and survival in a prospective study design.

METHODS

Patients sustaining TBI were prospectively identified during a 12-month period at an academic urban trauma center. Study inclusion criteria applied were: age ≥18 years, blunt injury mechanism and admission to neurosurgical intensive care unit (NICU). Early deaths (≤48h) and patients suffering extracranial injuries requiring invasive interventions or surgery were excluded. All consecutive admissions during a six-month period were administered intravenous Selenase^® for a maximum 10-day period and constituted cases. Patient demographics and outcomes up to six-months post-discharge were collected for analysis.

RESULTS

A total of 307 patients met inclusion criteria of which 125 were administered Selenase^®. Stepwise Poisson regression analysis identified five common predictors of poor functional outcome and in-hospital mortality: GCS ≤8, age ≥55 years, hypotension at admission, high Rotterdam score and invasive neurosurgical intervention. Selenase^® significantly reduced the risk of unfavourable functional outcomes, defined as GOS-E ≤4, at both discharge (adjusted RR 0.69, 95% CI 0.51-0.92, p=0.012) and at six months follow-up (adjusted RR 0.61, 95% CI 0.44-0.83, p=0.002). Following adjustment for significant group differences similar results were seen for functional outcome. Selenase^® did not improve survival (adjusted RR 1.12, 95% CI 0.62-2.02, p=0.709).

CONCLUSION

Intravenous Selenase^® treatment demonstrates a significant improvement in functional neurologic outcome. This effect is sustained at six months following discharge.

Selenium attenuates apoptosis, inflammation and oxidative stress in the blood and brain of aged rats with scopolamine-induced dementia

A potent antioxidant, selenium might modulate dementia-induced progression of brain and blood oxidative and apoptotic injuries. The present study explores whether selenium protects against experimental dementia (scopolamine, SCOP)-induced brain, and blood oxidative stress, apoptosis levels, and cytokine production in rats. Thirty-two rats were equally divided into four groups. The first group was used as an untreated control. The second group was treated with SCOP to induce dementia. The third and fourth groups received 1.5 mg/kg selenium (sodium selenite) and SCOP + selenium, respectively. Dementia was induced in the second and forth groups by intraperitoneal SCOP (1 mg/kg) administration. Brain, plasma, and erythrocyte lipid peroxidation levels as well as plasma TNF-α, interleukin (IL)-1β, and IL-4 levels were high in the SCOP group though they were low in selenium treatments. Selenium and selenium + SCOP treatments increased the lowered glutathione peroxidase activity, reduced glutathione, vitamins A and E concentrations in the brain, erythrocytes and plasma of the SCOP group. Apoptotic value expressions as active caspase-3, procaspase-9, and PARP were also increased by SCOP, while they were decreased by selenium and selenium + SCOP treatments. In conclusion, selenium induced protective effects against experimental dementia-induced brain, and blood oxidative injuries and apoptosis through regulation of cytokine production, vitamin E, glutathione concentrations, and glutathione peroxidase activity.

Early Administration of Selenium in Patients with Acute Traumatic Brain Injury: A Randomized Double-blinded Controlled Trial

Aim:

The present study was carried out to examine this hypothesis that administration of selenium can prevent the development of injuries by brain trauma and thus can modulate patients’ functional recovery and also improve posttraumatic outcome.

Materials and Methods:

This double-blinded controlled trial was carried out on 113 patients who were hospitalized following traumatic brain injury (TBI) with Glasgow Coma Scale score of 4–12 that were randomly assigned to receive selenium within 8 h after injury plus standard treatment group or routine standard treatment alone as the control. The primary endpoint was to assess patients’ functional recovery at 2 months after the injury based on extended Glasgow Outcome Scale score (GOS-E). Secondary outcomes included the changes in Full Outline of Unresponsiveness score (FOUR) score, Sequential Organ Failure Assessment (SOFA) score, and acute physiology and chronic health evaluation (APACHE) III score, side effects of selenium, length of Intensive Care Unit (ICU) stay, and length of hospital stay.

Results:

There was no difference in the length of ICU and hospital stay, the trend of the change in FOUR and SOFA scores within 15 days of first interventions, and the mean APACHE III score on the 1^st and 15^th days between the two groups. Mortality was 15.8% in selenium group and 19.6% in control group with no between-group difference. No difference was revealed between the two groups in appropriate outcome according to GOS-E score at 60 ± 10 days and also 30 ± 5 days according to the severity of TBI.

Conclusion:

This human trial study could not demonstrate beneficial effects of intravenous infusion of selenium in the improvement of outcomes in patients with acute TBI.

Connexin40 correlates with oxidative stress in brains of traumatic brain injury rats

BACKGROUND

Oxidative stress is an important factor in the pathophysiologic changes after traumatic brain injury (TBI). Connexin43 (Cx43) was reported to contribute to cerebral damage. However, the impacts of Cx40 have not been investigated in detail.

OBJECTIVE

In the present study, we hypothesized that Cx40 was involved in oxidative stress-induced brain injury after TBI.

METHODS

The controlled cortical impact (CCI) model was introduced to Wistar rats as a TBI model. Neurological deficits, oxidative stress and Cx40 were evaluated in TBI rats and N-acetylcysteine (NAC)-treated TBI rats. Neurological severity score (NSS) was used to assess neurological deficits. Brain infarction was measured by histo-staining. Brain edema was evaluated by measuring the brain water content. Cortex samples were collected to measure the tissue levels of malonyldialdehyde (MDA), nitric oxide (NO) and glutathione (GSH) and NADPH oxidase activity. Cx40 expression was determined by Western-blot.

RESULTS

TBI-induced brain injuries gradually increased from 6 h to 24 h post CCI, and the severity remained till 72 h. The level of oxidative stress was consistent with the extent of neurological deficits. Cx40 was upregulated after TBI in a linear correlated manner with increased oxidative stress. With NAC intervention, both neurological deficits and oxidative stress were significantly attenuated. Meanwhile, elevated Cx40 expression in cortex was also prevented by NAC treatment.

CONCLUSION

These studies revealed the relationship between levels of Cx40 and oxidative stress after TBI. The cortex Cx40 expression was positively correlated with the cerebral oxidative stress, indicating the involvement of Cx40 in the progress of brain damage.

Agomelatine reduces brain, kidney and liver oxidative stress but increases plasma cytokine production in the rats with chronic mild stress-induced depression

Agomelatine (AGOM) as an antidepressant acts both as a melatonin-receptor agonist and a selective serotonin-receptor antagonist. As a potent melatonin derived antioxidant, AGOM might modulate depression-induced lipid peroxidation and pro-inflammatory cytokines in brain, kidney and liver. The present study explores whether AGOM protects against experimental depression-induced brain, kidney and liver oxidative stress, and plasma cytokine production in rats with chronic mild stress (CMS)-induced depression. Thirty-six rats were divided into four groups. The first group was used as an untreated control. The second group received AGOM for 4 weeks. The third group was exposed to chronic mild stress (CMS) of 4 weeks for induction depression. The fourth group received 40 mg/kg AGOM and CMS for 4 weeks. Liver and kidney lipid peroxidation levels were high in the CMS group although they were low in AGOM treatments. AGOM and AGOM + CMS treatments increased the lowered glutathione peroxidase activity and reduced glutathione levels in brain, kidney and liver of CMS group. β-carotene, vitamin A and vitamin E concentrations in the brain, kidney and liver of the four groups were not changed by CMS and AGOM treatments. However, plasma TNF-α, interleukin (IL)-1β, and IL-4 levels were high in the CMS and AGOM group and their levels were further increased by the AGOM + CMS treatment. In conclusions, AGOM induced protective effects against experimental depression-induced brain, kidney, and liver oxidative injuries through regulation of the glutathione concentrations and glutathione peroxidase activity. However, plasma cytokine productions were increased by the AGOM treatment.

Rhein and rhubarb similarly protect the blood-brain barrier after experimental traumatic brain injury via gp91phox subunit of NADPH oxidase/ROS/ERK/MMP-9 signaling pathway

Oxidative stress chiefly contributes to the disruption of the BBB following traumatic brain injury (TBI). The Chinese herbal medicine rhubarb is a promising antioxidant in treating TBI. Here we performed in vivo and in vitro experiments to determine whether rhubarb and its absorbed bioactive compound protected the BBB after TBI by increasing ZO-1 expression through inhibition of gp91phox subunit of NADPH oxidase/ROS/ERK/MMP-9 pathway. Rats were subjected to the controlled cortical impact (CCI) model, and primary rat cortical astrocytes were exposed to scratch-wound model. The liquid chromatography with tandem mass spectrometry method showed that rhein was the compound absorbed in the brains of CCI rats after rhubarb administration. The wet-dry weights and Evans blue measurements revealed that rhubarb and rhein ameliorated BBB damage and brain edema in CCI rats. Western blots showed that rhubarb and rhein downregulated GFAP in vitro. RT-PCR, immunohistochemistry, Western blot and dichlorodihydrofluorescein diacetate analysis indicated that rhubarb prevented activation of gp91phox subunit of NADPH oxidase induced ROS production, subsequently inhibited ERK/MMP-9 pathway in vivo and in vitro. Interestingly, rhein and rhubarb similarly protected the BBB by inhibiting this signaling cascade. The results provide a novel herbal medicine to protect BBB following TBI via an antioxidative molecular mechanism.

Biological functions of selenium and its potential influence on Parkinson's disease

Parkinson's disease is characterized by the death of dopaminergic neurons, mainly in the substantia nigra, and causes serious locomotor dysfunctions. It is likely that the oxidative damage to cellular biomolecules is among the leading causes of neurodegeneration that occurs in the disease. Selenium is an essential mineral for proper functioning of the brain, and mainly due to its antioxidant activity, it is possible to exert a special role in the prevention and in the nutritional management of Parkinson's disease. Currently, few researchers have investigated the effects of selenium on Parkinson´s disease. However, it is known that very high or very low body levels of selenium can (possibly) contribute to the pathogenesis of Parkinson's disease, because this imbalance results in increased levels of oxidative stress. Therefore, the aim of this work is to review and discuss studies that have addressed these topics and to finally associate the information obtained from them so that these data and associations serve as input to new research.

Raloxifene and Tamoxifen Reduce PARP Activity, Cytokine and Oxidative Stress Levels in the Brain and Blood of Ovariectomized Rats

It is well known that 17β-estradiol (E2) has an antioxidant role on neurological systems in the brain. Raloxifene (RLX) and tamoxifen (TMX) are selective estrogen receptor modulators. An E2 deficiency stimulates mitochondrial functions for promoting apoptosis and increasing reactive oxygen species (ROS) production. However, RLX and TMX may reduce the mitochondrial ROS production via their antioxidant properties in the brain and erythrocytes of ovariectomized (OVX) rats. We aimed to investigate the effects of E2, RLX, and TMX on oxidative stress, apoptosis, and cytokine production in the brain and erythrocytes of OVX rats.Forty female rats were divided into five groups. The first group was used as a control group. The second group was the OVX group. The third, fourth, and fifth groups were OVX + E2, OVX + TMX, and OVX + RLX groups, respectively. E2, TMX, and RLX were given subcutaneously to the OVX + E2 and OVX + TMX, OVX + RLX groups for 14 days after the ovariectomy respectively.While brain and erythrocyte lipid peroxidation levels were high in the OVX group, they were low in the OVX + E2, OVX + RLX, and OVX + TMX groups. OVX + E2, OVX + RLX, and OVX + TMX treatments increased the lowered glutathione peroxidase activity in erythrocytes and the brain and reduced glutathione and vitamin E concentrations in the brain. β-carotene and vitamin A concentrations in the brain and TNF-α and interleukin (IL)-1β levels in the plasma of the five groups were not significantly changed by the treatments. However, increased plasma IL-4 levels and Western blot results for brain poly (ADP-ribose) polymerase (PARP) in the OVX groups were decreased by E2, TMX, and RLX treatments, although proapoptotic procaspase 3 and 9 activities were increased by the treatments.In conclusion, we observed that E2, RLX, and TMX administrations were beneficial on oxidative stress, inflammation, and PARP levels in the serum and brain of OVX rats by modulating antioxidant systems, DNA damage, and cytokine production.

Neuroprotection and antioxidants

Ischemia as a serious neurodegenerative disorder causes together with reperfusion injury many changes in nervous tissue. Most of the neuronal damage is caused by complex of biochemical reactions and substantial processes, such as protein agregation, reactions of free radicals, insufficient blood supply, glutamate excitotoxicity, and oxidative stress. The result of these processes can be apoptotic or necrotic cell death and it can lead to an irreversible damage. Therefore, neuroprotection and prevention of the neurodegeneration are highly important topics to study. There are several approaches to prevent the ischemic damage. Use of many modern therapeutical methods and the incorporation of several substances into the diet of patients is possible to stimulate the endogenous protective mechanisms and improve the life quality.

Systematic Review of Traumatic Brain Injury and the Impact of Antioxidant Therapy on Clinical Outcomes

BACKGROUND

Traumatic brain injury (TBI) is an acquired brain injury that occurs when there is sudden trauma that leads to brain damage. This acute complex event can happen when the head is violently or suddenly struck or an object pierces the skull or brain. The current principal treatment of TBI includes various pharmaceutical agents, hyperbaric oxygen, and hypothermia. There is evidence that secondary injury from a TBI is specifically related to oxidative stress. However, the clinical management of TBI often does not include antioxidants to reduce oxidative stress and prevent secondary injury.

AIMS

The purpose of this article is to examine current literature regarding the use of antioxidant therapies in treating TBI. This review evaluates the evidence of antioxidant therapy as an adjunctive treatment used to reduce the underlying mechanisms involved in secondary TBI injury.

METHODS

A systematic review of the literature published between January 2005 and September 2015 was conducted. Five databases were searched including CINAHL, PubMed, the Cochrane Library, PsycINFO, and Web of Science.

FINDINGS

Critical evaluation of the six studies that met inclusion criteria suggests that antioxidant therapies such as amino acids, vitamins C and E, progesterone, N-acetylcysteine, and enzogenol may be safe and effective adjunctive therapies in adult patients with TBI. Although certain limitations were found, the overall trend of using antioxidant therapies to improve the clinical outcomes of TBI was positive.

LINKING EVIDENCE TO ACTION

By incorporating antioxidant therapies into practice, clinicians can help attenuate the oxidative posttraumatic brain damage and optimize patients' recovery.

Hypocretinergic and cholinergic contributions to sleep-wake disturbances in a mouse model of traumatic brain injury

Disorders of sleep and wakefulness occur in the majority of individuals who have experienced traumatic brain injury (TBI), with increased sleep need and excessive daytime sleepiness often reported. Behavioral and pharmacological therapies have limited efficacy, in part, because the etiology of post-TBI sleep disturbances is not well understood. Severity of injuries resulting from head trauma in humans is highly variable, and as a consequence so are their sequelae. Here, we use a controlled laboratory model to investigate the effects of TBI on sleep-wake behavior and on candidate neurotransmitter systems as potential mediators. We focus on hypocretin and melanin-concentrating hormone (MCH), hypothalamic neuropeptides important for regulating sleep and wakefulness, and two potential downstream effectors of hypocretin actions, histamine and acetylcholine. Adult male C57BL/6 mice (n=6-10/group) were implanted with EEG recording electrodes and baseline recordings were obtained. After baseline recordings, controlled cortical impact was used to induce mild or moderate TBI. EEG recordings were obtained from the same animals at 7 and 15 days post-surgery. Separate groups of animals (n=6-8/group) were used to determine effects of TBI on the numbers of hypocretin and MCH-producing neurons in the hypothalamus, histaminergic neurons in the tuberomammillary nucleus, and cholinergic neurons in the basal forebrain. At 15 days post-TBI, wakefulness was decreased and NREM sleep was increased during the dark period in moderately injured animals. There were no differences between groups in REM sleep time, nor were there differences between groups in sleep during the light period. TBI effects on hypocretin and cholinergic neurons were such that more severe injury resulted in fewer cells. Numbers of MCH neurons and histaminergic neurons were not altered under the conditions of this study. Thus, we conclude that moderate TBI in mice reduces wakefulness and increases NREM sleep during the dark period, effects that may be mediated by hypocretin-producing neurons and/or downstream cholinergic effectors in the basal forebrain.

Diabetes enhances oxidative stress-induced TRPM2 channel activity and its control by N-acetylcysteine in rat dorsal root ganglion and brain

N-acetylcysteine (NAC) is a sulfhydryl donor antioxidant that contributes to the regeneration of glutathione (GSH) and also scavengers via a direct reaction with free oxygen radicals. Recently, we observed a modulatory role of NAC on GSH-depleted dorsal root ganglion (DRG) cells in rats. NAC may have a protective role on oxidative stress and calcium influx through regulation of the TRPM2 channel in diabetic neurons. Therefore, we investigated the effects of NAC on DRG TRPM2 channel currents and brain oxidative stress in streptozotocin (STZ)-induced diabetic rats. Thirty-six rats divided into four groups: control, STZ, NAC and STZ + NAC. Diabetes was induced in the STZ and STZ + NAC groups by intraperitoneal STZ (65 mg/kg) administration. After the induction of diabetes, rats in the NAC and STZ + NAC groups received NAC (150 mg/kg) via gastric gavage. After 2 weeks, DRG neurons and the brain cortex were freshly isolated from rats. In whole-cell patch clamp experiments, TRPM2 currents in the DRG following diabetes induction with STZ were gated by H2O2. TRPM2 channel current densities in the DRG and lipid peroxidation levels in the DRG and brain were higher in the STZ groups than in controls; however, brain GSH, GSH peroxidase (GSH-Px), vitamin C and vitamin E concentrations and DRG GSH-Px activity were decreased by diabetes. STZ + H2O2-induced TRPM2 gating was totally inhibited by NAC and partially inhibited by N-(p-amylcinnamoyl) anthranilic acid (ACA) and 2-aminoethyl diphenylborinate (2-APB). GSH-Px activity and lipid peroxidation levels were also attenuated by NAC treatment. In conclusion, we observed a modulatory role of NAC on oxidative stress and Ca(2+) entry through the TRPM2 channel in the diabetic DRG and brain. Since excessive oxidative stress and overload Ca(2+) entry are common features of neuropathic pain, our findings are relevant to the etiology and treatment of pain neuropathology in DRG neurons.

Traumatic Brain Injury-Induced Neuronal Apoptosis is Reduced Through Modulation of PI3K and Autophagy Pathways in Mouse by FTY720

FTY720 is a synthetic compound produced by modification of metabolite from Isaria sinclairii. It is a novel type of immunosuppressive agent inhibiting lymphocyte egress from secondary lymphoid tissues, thereby causing peripheral lymphopenia. Growing evidences have suggested that apoptosis and autophagy were involved in the secondary brain injury after traumatic brain injury (TBI) although FTY720 exerted neuroprotective effects in a variety of neurological diseases except TBI. The present study was aimed to investigate the role of FTY720 in a mouse model of TBI. In experiment 1, ICR mice were divided into four groups: sham group, TBI group, TBI + vehicle group, and TBI + FTY720 group. And the injured cerebral cortex (including both contused and penumbra) was used for analysis. We found that FTY720 administration after TBI improved neurobehavioral function, alleviated brain edema, accompanied by modulation of apoptotic indicators such as Bcl-2, Bcl-xL, Bax, and cytochrome c. In experiment 2, ICR mice were also divided into four groups: sham group, TBI + vehicle group, TBI + FTY720 group, and TBI + FTY720 + inhibitors group. And the injured cerebral cortex (including both contused and penumbra) was used for analysis. We found that FTY720 increased the expression of phospho-protein kinase B (AKT) and some autophagy markers such as LC3 and Beclin 1. In addition, the apoptosis inhibition effect of FTY720 was partly abrogated by the phosphatidylinositide 3-kinases (PI3K)/AKT pathway inhibitor LY294002 and autophagy inhibitor 3-methyladenine. Collectively, our data provide the first evidence that FTY720 exerted neuroprotective effects after TBI, at least in part, through the activation of PI3K/AKT pathway and autophagy.

The Circulating Levels of Selenium, Zinc, Midkine, Some Inflammatory Cytokines, and Angiogenic Factors in Mitral Chordae Tendineae Rupture

Chordae tendineae rupture process is associated with increased production of inflammatory and angiogenesis mediators in connective tissues, which contributes to chronic inflammation and pathogenesis of degenerative chordae. A few trace elements are known to possess antioxidant, anti-inflammatory, and antiangiogenic properties. Therefore, the aim of this study was to determine whether zinc, selenium, midkine (MK), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α), vascular endothelial growth factor-A (VEGF-A), platelet-derived growth factor-BB (PDGF-BB), and reduced glutathione (GSH) levels are associated with inflammation and angiogenesis processes in the context of a potential etiology causing aggravation of mitral regurgitation and/or ruptured chordae tendineae. Seventy-one subjects comprising 34 patients with mitral chordae tendineae rupture (MCTR) and 37 healthy controls diagnosed on the basis of their clinical profile and transthoracic echocardiography were included in this study. The levels of GSH, MK, selenium, and zinc were found to be lower in the patients group when compared to control group. There were no significant difference in plasma TNF-α, IL-1β, IL-6, IL-8, VEGF-A, and PDGF-BB levels between two groups. There were positive significant correlations between MK and GSH, MK, and selenium levels in patients with MCTR. According to our data in which selenium, zinc, MK, and GSH decreased in MCTR patients, inflammatory response, oxidative stress, and trace element levels may contribute to etiopathogenesis of mitral regurgitation and/or ruptured chordae tendineae.

Dietary supplementation of organic selenium could improve performance, antibody response, and yolk oxidative stability in laying hens fed on diets containing oxidized fat

The present study was carried out to investigate the effect of dietary supplementation of organic selenium (Se) on performance, egg quality indices, and yolk oxidative stability in laying hens fed diets with different fat sources. A total of 270 Hy-line W-36 Leghorn hens of 47 weeks of age were randomly distributed into the 5 replicate cages of 9 dietary treatments. Experimental diets consisted of a 3 × 3 factorial arrangement of treatments with three different fat sources (soybean oil, SO; yellow grease, YG; and palm fat powder, PFP) and three different levels of supplemental Se (0, 0.2, and 0.4 mg/kg of diet) as supplied by zinc-L-selenomethionine (ZnSeMet) complex, which fed during a 77-day feeding trial including 7 days for adaptation and 70 days as the main recording period. Results showed that the highest (P < 0.05) egg weights assigned to the hens fed on SO-supplemented diets. Hen-day egg production was affected by both dietary fat source (P < 0.01) and Se level (P < 0.05) throughout the trial period. Regardless of dietary fat source, dietary supplementation of ZnSeMet improved (P < 0.05) egg mass during all trial periods. Moreover, the significant (P < 0.05) fat  source× Se interactions were observed for egg mass, so that dietary supplementation with 0.4 mg/kg Se was more effective in diets supplemented with YG. Although feed intake was not affected by experimental diets during the first 35-day period, dietary inclusion of PFP reduced feed intake during both second 35-day (P < 0.01) and entire trial period (P < 0.05). The best (P < 0.01) feed conversion ratio during the first 35-day period was assigned to the birds fed on SO-diets, followed by those fed YG-diets. Dietary supplementation of ZnSeMet improved (P < 0.05) feed efficiency during the first 35-day period. Supplementation of ZnSeMet into the diets increased yolk index, with more impact in hens fed on YG-diets. The highest concentration of yolk malondialdehyde was observed in YG-fed groups, and ZnSeMet supplementation of diets decreased (P < 0.05) yolk malondialdehyde. The highest (P<0.01) glutathione peroxidase activity was observed for hens fed on diets supplemented by YG, followed by those on SO-diets. Although different fat sources had no effect on antibody titer against Newcastle disease virus, supplemental ZnSeMet improved (P < 0.05) antibody response. The present findings indicate that dietary supplementation of ZnSeMet could improve performance parameters and egg oxidative stability in laying hens, with the highest impact in diets containing oxidized (high peroxide values) fat sources.

[Huntington's disease]

BACKGROUND

Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by hyperkinetic movements, psychiatric (e.g. depression and psychosis) and cognitive symptoms (frontal lobe dementia). In Germany approximately 8000 patients suffer from HD.

OBJECTIVES

The paper reviews the clinical course, epidemiology, genetics, differential diagnoses, pathophysiology, symptomatics and causal treatment options.

METHODS

Publications on animal and human HD studies and trials and reviews available in Medline have been taken into account.

RESULTS

Only genetic testing allows diagnostic certainty. The CAG repeat length influences age of onset, disease course and life expectancy. The mechanism by which mutant huntingtin protein (mHTT) causes HD is complex and poorly understood but leads to cell death, in particular in striatal neurons. In clinical trials antioxidants (e.g. coenzyme Q10), selisistat, PBT2, cysteamine, N-methyl-D-aspartate (NMDA)-receptor antagonists and tyrosine kinase B receptor agonists have been studied in HD.

CONCLUSION

No disease-modifying therapy is currently available for HD; however, gene silencing, e.g. through RNA interference, is a promising technique which could lead to effective therapies in due course.

Protective effects of riboflavin and selenium on brain microsomal Ca2+-ATPase and oxidative damage caused by glyceryl trinitrate in a rat headache model

Migraine headaches are considered to be associated with increased mitochondrial energy metabolism. Mitochondrial oxidative stress is also important in migraine headache pathophysiology although riboflavin and selenium (Se) induced a modulator role on mitochondrial oxidative stress in the brain. The current study aimed to determine the effects of Se with/without riboflavin on the microsomal membrane Ca(2+)-ATPase (MMCA), lipid peroxidation, antioxidant, and electroencephalography (EEG) values in glyceryl trinitrate (GTN)-induced brain injury rats. Thirty-two rats were randomly divided into four groups. The first group was used as the control, and the second group was the GTN group. Se and Se plus oral riboflavin were administered to rats constituting the third and fourth groups for 10 days prior to GTN administration. The second, third, and fourth groups received GTN to induce headache. Ten hours after the administration of GTN, the EEG records and brain cortex samples were obtained for all groups. Brain cortex microsomes were obtained from the brain samples. The brain and microsomal lipid peroxidation levels were higher in the GTN group compared to the control group, whereas they were decreased by selenium and selenium + riboflavin treatments. Vitamin A, vitamin C, vitamin E, and reduced glutathione (GSH) concentrations of the brain and MMCA, GSH and glutathione peroxidase values of microsomes were decreased by the GTN administration, although the values and β-carotene concentrations were increased by Se and Se + riboflavin treatments. There was no significant change in EEG records of the four groups. In conclusion, Se with/without riboflavin administration protected against GTN-induced brain oxidative toxicity by inhibiting free radicals and the modulation of MMCA activity and supporting the antioxidant redox system.

N-acetyl cysteine reduces oxidative toxicity, apoptosis, and calcium entry through TRPV1 channels in the neutrophils of patients with polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is a common inflammatory and oxidant disease with an uncertain pathogenesis. N-acetyl cysteine (NAC) decreases oxidative stress, intracellular free calcium ion [Ca(2+)]i, and apoptosis levels in human neutrophil. We aimed to investigate the effects of NAC on apoptosis, oxidative stress, and Ca(2+) entry through transient receptor potential vanilloid 1 (TRPV1) and TRP melastatin 2 (TRPM2) channels in neutrophils from patients with PCOS. Neutrophils isolated from PCOS group were investigated in three settings: (1) after incubation with TRPV1 channel blocker capsazepine or TRPM2 channel blocker 2-aminoethyl diphenylborinate (2-APB), (2) after supplementation with NAC (for 6 weeks), and (3) with combination (capsazepine + 2-APB + NAC) exposure. The neutrophils in TRPM2 and TRPV1 experiments were stimulated by N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP; 1 μM) and capsaicin (10 μM) as concentration agonists, respectively. Neutrophil lipid peroxidation and capsaicin-induced increase in [Ca(2+)]i concentrations were reduced by capsazepine and NAC treatments. However, the [Ca(2+)]i concentration did not change by fMLP stimulation. Neutrophil lipid peroxidation, apoptosis, caspase-3, caspase-9, cytosolic reactive oxygen species production, and mitochondrial membrane depolarization values were decreased by NAC treatment although neutrophil glutathione peroxidase and reduced glutathione levels were increased by the NAC treatment. Serum lipid peroxidation, luteinizing hormone, testosterone, insulin, interleukin-1 beta, and homocysteine levels were decreased by NAC treatment although serum vitamin A, beta-carotene, vitamin E, and total antioxidant status were increased by the NAC treatment. In conclusion, NAC reduced oxidative stress, apoptosis, cytokine levels, and Ca(2+) entry through TRPV1 channel, which provide supportive evidence that oxidative stress and TRPV1 channel plays a key role in etiology of PCOS.

Reduction in traumatic brain injury-induced oxidative stress, apoptosis, and calcium entry in rat hippocampus by melatonin: Possible involvement of TRPM2 channels

Melatonin, which is a very effective reactive oxygen species (ROS) scavenger, acts through a direct reaction with free radicals. Ca(2+) entry induced by traumatic brain injury (TBI) has deleterious effects on human hippocampal function. TRPM2 is a Ca(2+) permeable non-selective channel in hippocampal neurons, and its activation of during oxidative stress has been linked to cell death. Despite the importance of oxidative stress in TBI, its role in apoptosis and Ca(2+) entry in TBI is poorly understood. Therefore, we tested the effects of melatonin on apoptosis, oxidative stress, and Ca(2+) entry through the TRPM2 channel in the hippocampal neurons of TBI-induced rats. Thirty-two rats were divided into the following four groups: control, melatonin, TBI, and TBI + melatonin groups. Melatonin (5 mg/kg body weight) was intraperitoneally given to animals in the melatonin group and the TBI + melatonin group after 1 h of brain trauma. Hippocampal neurons were freshly isolated from the four groups, incubated with a nonspecific TRPM2 blocker (2-aminoethyl diphenylborinate, 2-APB), and then stimulated with cumene hydroperoxide. Apoptosis, caspase-3, caspase-9, intracellular ROS production, mitochondrial membrane depolarization and intracellular free Ca(2+) ([Ca(2+)]i) values were high in the TBI group, and low in the TBI + melatonin group. The [Ca(2+)]i concentration was decreased in the four groups by 2-APB. In our TBI experimental model, TRPM2 channels were involved in Ca(2+) entry-induced neuronal death, and the negative modulation of the activity of this channel by melatonin pretreatment may account for the neuroprotective activity of TRPM2 channels against oxidative stress, apoptosis, and Ca(2+) entry.

Selenium suppresses lipopolysaccharide-induced fibrosis in peritoneal mesothelial cells through inhibition of epithelial-to-mesenchymal transition

Peritoneal fibrosis resulting from long-term clinical peritoneal dialysis has been the main reason of dropout from peritoneal dialysis. Peritonitis as a common complication of peritoneal dialysis treatment may lead to the occurrences of peritoneal fibrosis. We cultured peritoneal mesothelial cells with lipopolysaccharides (LPS) in order to stimulate the environment of peritonitis and investigate whether lipopolysaccharides could induce epithelial-to-mesenchymal transition (EMT). Oxidative stress could stimulate fibrogenesis while selenium has antioxidant properties. So, this study also explored whether selenium supplementation affects lipopolysaccharide-induced EMT and fibrosis. We found that lipopolysaccharides could activate EMT changes such as the loss of E-cadherin and the increase of α-smooth muscle actin (α-SMA), collagen I, vimentin, and fibronectin (FN), while selenium inhibits EMT by modulating reactive oxygen species (ROS) generation and ROS/MMP-9 signaling pathways in peritoneal mesothelial cells. Moreover, it was revealed that selenium decreased the EMT events of peritoneal mesothelial cells via inhibition of PI3k/AKT pathways. In conclusion, these findings enable a better understanding of the mechanism of peritoneal fibrosis and explore a new idea for the prevention and treatment.

Electromagnetic radiation (Wi-Fi) and epilepsy induce calcium entry and apoptosis through activation of TRPV1 channel in hippocampus and dorsal root ganglion of rats

Incidence rates of epilepsy and use of Wi-Fi worldwide have been increasing. TRPV1 is a Ca(2+) permeable and non-selective channel, gated by noxious heat, oxidative stress and capsaicin (CAP). The hyperthermia and oxidant effects of Wi-Fi may induce apoptosis and Ca(2+) entry through activation of TRPV1 channel in epilepsy. Therefore, we tested the effects of Wi-Fi (2.45 GHz) exposure on Ca(2+) influx, oxidative stress and apoptosis through TRPV1 channel in the murine dorsal root ganglion (DRG) and hippocampus of pentylentetrazol (PTZ)-induced epileptic rats. Rats in the present study were divided into two groups as controls and PTZ. The PTZ groups were divided into two subgroups namely PTZ + Wi-Fi and PTZ + Wi-Fi + capsazepine (CPZ). The hippocampal and DRG neurons were freshly isolated from the rats. The DRG and hippocampus in PTZ + Wi-Fi and PTZ + Wi-Fi + CPZ groups were exposed to Wi-Fi for 1 hour before CAP stimulation. The cytosolic free Ca(2+), reactive oxygen species production, apoptosis, mitochondrial membrane depolarization, caspase-3 and -9 values in hippocampus were higher in the PTZ group than in the control although cell viability values decreased. The Wi-Fi exposure induced additional effects on the cytosolic Ca(2+) increase. However, pretreatment of the neurons with CPZ, results in a protection against epilepsy-induced Ca(2+) influx, apoptosis and oxidative damages. In results of whole cell patch-clamp experiments, treatment of DRG with Ca(2+) channel antagonists [thapsigargin, verapamil + diltiazem, 2-APB, MK-801] indicated that Wi-Fi exposure induced Ca(2+) influx via the TRPV1 channels. In conclusion, epilepsy and Wi-Fi in our experimental model is involved in Ca(2+) influx and oxidative stress-induced hippocampal and DRG death through activation of TRPV1 channels, and negative modulation of this channel activity by CPZ pretreatment may account for the neuroprotective activity against oxidative stress.