Cerebral Hypoperfusion Research Articles

Neuroretinal and microvascular retinal features in dementia with Lewy body assessed by optical coherence tomography angiography.

To explore retinal changes in patients with Dementia with Lewy Bodies (DLB) using Spectral Domain-Optical Coherence Tomography (SD-OCT) and Optical Coherence Tomography Angiography (OCTA), aiming to identify potential biomarkers for diagnosis and monitoring. A cross-sectional study analyzed 15 DLB patients and 18 matched controls. Participants underwent physical, neurological, neuropsychological, and ophthalmological evaluations, including SD-OCT and OCTA. Logistic regression, adjusted for age, sex, and inter-eye correlation, was employed to identify retinal alterations in patients affected by DLB. OCTA revealed that DLB is associated with reduced superficial and deep vessel densities (SVD and DVD) in the macula (p < 0.01), as well as decreased peripapillary vessel density (ppVD, p < 0.01). SD-OCT parameters showed correlations with DLB, including reduced central macular thickness (CMT, p < 0.001) and thinning of the ganglion cell layer-inner plexiform layer (GCL-IPL, p < 0.01). Logistic regression (R²=0.26) identified reduced ppVD as a significant predictor of DLB (p = 0.030). Impairments in retinal capillaries, especially lower ppVD, might mirror cerebral hypoperfusion in DLB, potentially due to reduced Vascular Endothelial Growth Factor (VEGF) levels and increased α-synuclein. Further investigations are warranted to confirm the causal relationship between these observations, disease severity, and progression, as well as their potential role as biomarkers for DLB.

Dried Blood Spot Metabolome Features of Ischemic-Hypoxic Encephalopathy: A Neonatal Rat Model.

Hypoxic-ischemic encephalopathy (HIE) is a severe neurological disorder caused by perinatal asphyxia with significant consequences. Early recognition and intervention are crucial, with therapeutic hypothermia (TH) being the primary treatment, but its efficacy depends on early initiation of treatment. Accurately assessing the HIE severity in neonatal care poses challenges, but omics approaches have made significant contribution to understanding its complex pathophysiology. Our study further explores the impact of HIE on the blood metabolome over time and investigated changes associated with hypothermia's therapeutic effects. Using a rat model of hypoxic-ischemic brain injury, we comprehensively analyzed dried blood spot samples for fat-soluble compounds using HPLC-MS. Our research shows significant changes in the blood metabolome after HIE, with a particularly rapid recovery of lipid metabolism observed. Significant changes in lipid metabolites were observed after 3 h of HIE, including increases in ceramides, carnitines, certain fatty acids, phosphocholines, and phosphoethanolamines, while sphingomyelins and N-acylethanolamines (NAEs) decreased (p < 0.05). Furthermore, NAEs were found to be significant features in the OPLS-DA model for HIE diagnosis, with an area under the curve of 0.812. TH showed a notable association with decreased concentrations of ceramides. Enrichment analysis further corroborated these observations, showing modulation in several key metabolic pathways, including arachidonic acid oxylipin metabolism, eicosanoid metabolism via lipooxygenases, and leukotriene C4 synthesis deficiency. Our study reveals dynamic changes in the blood metabolome after HIE and the therapeutic effects of hypothermia, which improves our understanding of the pathophysiology of HIE and could lead to the development of new rapid diagnostic approaches for neonatal HIE.

Blood product transfusion practices in neonates with hypoxic-ischemic encephalopathy.

Blood product transfusion is a common practice in infants with hypoxic-ischemic encephalopathy (HIE) undoing therapeutic hypothermia (TH). The advantages and disadvantages of conservative or liberal transfusion practices in this fragile population are unknown. Study aims to characterize the transfusion practices in infants with HIE and investigate the association with outcome. We conducted a retrospective cohort study at a single level IV NICU, evaluating transfusion thresholds, as well as the association between hematological abnormalities or blood product transfusions and outcomes in infants admitted with HIE. By univariate analysis, FFP transfusion was associated with increased in-hospital death. However, multivariate analysis adjusting for HIE severity demonstrated no association between hematological abnormality or blood product transfusion and death, nor with neurodevelopmental impairment. No association was found between hematological blood product transfusion and death or neurodevelopmental impairment in a retrospective single NICU study of infants with HIE.

Pathophysiology of syncope: current concepts and their development.

Syncope is a symptom in which transient loss of consciousness occurs as a consequence of a self-limited, spontaneously terminating period of cerebral hypoperfusion. Many circulatory disturbances (e.g. brady- or tachyarrhythmias, reflex cardioinhibition-vasodepression-hypotension) may trigger a syncope or near-syncope episode, and identifying the cause(s) is often challenging. Some syncope may involve multiple etiologies operating in concert, whereas in other cases multiple syncope events may be due to various differing causes at different times. In this communication, we address the current understanding of the principal contributors to syncope pathophysiology including examination of the manner in which concepts evolved, an overview of factors that constitute consciousness and loss of consciousness, and aspects of neurovascular control and communication that are impacted by cerebral hypoperfusion leading to syncope. Emphasis focuses on 1) current understanding of the way transient systemic hypotension impacts brain blood flow and brain function; 2) the complexity and temporal sequence of vascular, humoral, and cardiac factors that may accompany the most common causes of syncope; 3) the range of circumstances and disease states that may lead to syncope; and 4) clinical features associated with syncope and in particular the reflex syncope syndromes.

2,3-Diphosphoglyceric Acid Alleviating Hypoxic-Ischemic Brain Damage through p38 MAPK Modulation.

Neonatal hypoxic-ischemic encephalopathy (HIE) is a critical condition characterized by significant brain damage due to insufficient blood flow and oxygen delivery at birth, leading to high rates of neonatal mortality and long-term neurological deficits worldwide. 2,3-Diphosphoglyceric acid (2,3-DPG), a small molecule metabolite prevalent in erythrocytes, plays an important role in regulating oxygen delivery, but its potential neuroprotective role in hypoxic-ischemic brain damage (HIBD) has yet to be fully elucidated. Our research reveals that the administration of 2,3-DPG effectively reduces neuron damage caused by hypoxia-ischemia (HI) both in vitro and in vivo. We observed a notable decrease in HI-induced neuronal cell apoptosis, attributed to the downregulation of Bax and cleaved-caspase 3, alongside an upregulation of Bcl-2 expression. Furthermore, 2,3-DPG significantly alleviates oxidative stress and mitochondrial damage induced by oxygen-glucose deprivation/reperfusion (OGD/R). The administration of 2,3-DPG in rats subjected to HIBD resulted in a marked reduction in brain edema and infarct volume, achieved through the suppression of neuronal apoptosis and neuroinflammation. Using RNA-seq analysis, we validated that 2,3-DPG offers protection against neuronal apoptosis under HI conditions by modulating the p38 MAPK pathway. These insights indicated that 2,3-DPG might act as a promising novel therapeutic candidate for HIE.

Efficacy of therapeutic hypothermia on mild neonatal hypoxic-ischemic encephalopathy: a prospective randomized controlled study

To investigate the efficacy of therapeutic hypothermia on mild neonatal hypoxic-ischemic encephalopathy (HIE). A prospective study was performed on 153 neonates with mild HIE who were born from September 2019 to September 2023. These neonates were randomly divided into two groups: therapeutic hypothermia (n=77) and non-therapeutic hypothermia group (n=76). The short-term clinical efficacy of the two groups were compared. Barkovich scoring system was used to analyze the severity of brain injury shown on magnetic resonance imaging (MRI) between the two groups. There were no significant differences in gestational age, gender, birth weight, mode of birth, and Apgar score between the therapeutic hypothermia and non-therapeutic hypothermia groups (P>0.05). There were no significant differences in the incidence rates of sepsis, arrhythmia, persistent pulmonary hypertension and pulmonary hemorrhage and the duration of mechanical ventilation within the first 72 hours after birth between the two groups. The therapeutic hypothermia group had longer prothrombin time within the first 72 hours after birth and a longer hospital stay (P<0.05). Compared with the non-therapeutic hypothermia group, the therapeutic hypothermia group had lower incidence rates of MRI abnormalities (30% vs 57%), moderate to severe brain injury on MRI (5% vs 28%), and watershed injury (27% vs 51%) (P<0.05), as well as lower medium watershed injury score (0 vs 1) (P<0.05). Therapeutic hypothermia can reduce the incidence rates of MRI abnormalities and watershed injury, without obvious adverse effects, in neonates with mild HIE, suggesting that therapeutic hypothermia may be beneficial in neuroprotection in these neonates.

Spastic Equinovarus Foot Deformity.

Acute brain injuries are caused by a variety of etiologies, each potentially disrupting neurological function. The neurologic impairments are on a spectrum of severity often creating functional barriers to completing activities of daily living. Initial treatment starts immediately upon diagnosis and requires a multimodal approach working to prevent systemic changes. Therapy, bracing treatment, injections, and pharmacologic treatments are the mainstay of early intervention. Worsening upper motor neurological impairment associated with involuntary muscle hyperactivity can lead to a spastic equinovarus foot deformity. Spastic equinovarus foot deformities secondary to anoxic brain injuries or traumatic brain injury pose a challenging situation for orthopaedic surgeons because of associated cognitive impairment, spastic tone, and extensive soft-tissue contractures prohibiting bracing treatment. Tendon releases and transfers in combination with functional bracing treatment are initially attempted, and selective fusions are performed for severe cases. Surgical indications are primarily focused on obtaining a balanced, braceable, functional lower extremity with a plantigrade foot.

Perinatal Airway Management Mandibular Anomalies: A National Inpatient Cohort Analysis.

To characterize incidence of mandibular anomalies (MAs) and compare gestational age, airway interventions, and complications among individuals with MA phenotypes (isolated retrognathia, isolated micrognathia, syndromic micrognathia, micrognathia plus cleft palate/cleft lip and palate, agnathia/micrognathia plus cervical auricle/otocephaly, and agnathia/micrognathia plus microstomia) and unaffected individuals. The Healthcare Cost and Utilization Project Kids' Inpatient Database was used to collect data over a 20-year period beginning in 2000. Interventions were classified as perinatal when performed on day of life (DOL) 0 or 1 and subsequent when performed during the birth hospitalization after DOL 1. Hypoxic complications included cardiac arrest, birth asphyxia, hypoxic-ischemic encephalopathy, anoxic brain damage, intraventricular hemorrhage or cerebral infarction. Descriptive statistics are reported, and the Rao-Scott chi-square test compared groups. MAs affected 119 per 100,000 birth visits. Preterm delivery was more frequent for all MA phenotypes. Individuals with MA phenotypes are more likely to require medical attention (airway intervention on DOL 0 or 1 OR no airway intervention received but patient sustained hypoxic complication/mortality): 16.2%-70.7% vs. 3.8%, p < 0.01. Despite receipt of airway interventions at a higher rate, collectively individuals with MAs who received an airway intervention on DOL 0 or 1 have a mildly elevated risk of hypoxic complication or mortality (32.4% vs. 26.4%, p < 0.01). Preterm birth is more common, however, does not account for the elevated rate of airway intervention. Individuals with MAs require higher rates of medical attention, and current airway management paradigms are insufficient to prevent complications and mortality. III Laryngoscope, 2024.

Resveratrol Mitigates Cognitive Impairments and Cholinergic Cell Loss in the Medial Septum in a Mouse Model of Gradual Cerebral Hypoperfusion.

Vascular cognitive impairment and dementia (VCID) is the second leading cause of dementia. There is currently no effective treatment for VCID. Resveratrol (RSV) is considered an antioxidant; however, our group has observed pleiotropic effects in stroke paradigms, suggesting more effects may contribute to mechanistic changes beyond antioxidative properties. The main goal of this study was to investigate if administering RSV twice a week could alleviate cognitive declines following the induction of a VCID model. Additionally, our aim was to further describe whether this treatment regimen could decrease cell death in brain areas vulnerable to changes in cerebral blood flow, such as the hippocampus and medial septum. We hypothesized RSV treatments in a mouse model of gradual cerebral hypoperfusion protect against cognitive impairment. We utilized gradual bilateral common carotid artery stenosis (GBCCAS) via the surgical implantation of ameroid constrictor devices. RSV treatment was administered on the day of implantation and twice a week thereafter. Cerebral perfusion was measured by laser speckle contrast imaging, and cognitive functions, including the recognition memory, the spatial working memory, and associative learning, were assessed by novel object recognition (NOR), Y-maze testing, and contextual fear conditioning (CFC), respectively. RSV treatment did not alleviate cerebral perfusion deficits but mitigated cognitive deficits in CFC and NOR after GBCCAS. Despite these deficits, no hippocampal pathology was observed; however, cholinergic cell loss in the medial septum was significantly increased after GBCCAS. This cholinergic cell loss was mitigated by RSV. This study describes a novel mechanism by which chronic RSV treatments protect against a VCID-induced cognitive decline through the preservation of cholinergic cell viability to improve memory performance.

Associations of Cerebral Blood Flow Patterns With Gray and White Matter Structure in Patients With Temporal Lobe Epilepsy.

Neuroimaging studies in patients with temporal lobe epilepsy (TLE) show widespread brain network alterations beyond the mesiotemporal lobe. Despite the critical role of the cerebrovascular system in maintaining whole-brain structure and function, changes in cerebral blood flow (CBF) remain incompletely understood in the disease. Here, we studied whole-brain perfusion and vascular network alterations in TLE and assessed its associations with gray and white matter compromises and various clinical variables. We included individuals with and without pharmaco-resistant TLE who underwent multimodal 3T MRI, including arterial spin labelling, structural, and diffusion-weighted imaging. Using surface-based MRI mapping, we generated individualized cortico-subcortical profiles of perfusion, morphology, and microstructure. Linear models compared regional CBF in patients with controls and related alterations to morphological and microstructural metrics. We further probed interregional vascular networks in TLE, using graph theoretical CBF covariance analysis. The effects of disease duration were explored to better understand the progressive changes in perfusion. We assessed the utility of perfusion in separating patients with TLE from controls using supervised machine learning. Compared with control participants (n = 38; mean ± SD age 34.8 ± 9.3 years; 20 females), patients with TLE (n = 24; mean ± SD age 35.8 ± 10.6 years; 12 females) showed widespread CBF reductions predominantly in fronto-temporal regions (Cohen d -0.69, 95% CI -1.21 to -0.16), consistent in a subgroup of patients who remained seizure-free after surgical resection of the seizure focus. Parallel structural profiling and network-based models showed that cerebral hypoperfusion may be partially constrained by gray and white matter changes (8.11% reduction in Cohen d) and topologically segregated from whole-brain perfusion networks (area under the curve -0.17, p < 0.05). Negative effects of progressive disease duration further targeted regional CBF profiles in patients (r = -0.54, 95% CI -0.77 to -0.16). Perfusion-derived classifiers discriminated patients from controls with high accuracy (71% [70%-82%]). Findings were robust when controlling for several methodological confounds. Our multimodal findings provide insights into vascular contributions to TLE pathophysiology affecting and extending beyond mesiotemporal structures and highlight their clinical potential in epilepsy diagnosis. As our work was cross-sectional and based on a single site, it motivates future longitudinal studies to confirm progressive effects, ideally in a multicentric setting.

Tobacco cigarette smoking induces cerebrovascular dysfunction followed by oxidative neuronal injury with the onset of cognitive impairment.

While chronic smoking triggers cardiovascular disease, controversy remains regarding its effects on the brain and cognition. We investigated the effects of long-term cigarette smoke (CS) exposure (CSE) on cerebrovascular function, neuronal injury, and cognition in a novel mouse exposure model. Longitudinal studies were performed in CS or air-exposed mice, 2 hours/day, for up to 60 weeks. Hypertension and carotid vascular endothelial dysfunction (VED) occurred by 16 weeks of CSE, followed by reduced carotid artery blood flow, with oxidative stress detected in the carotid artery, and subsequently in the brain of CS-exposed mice with generation of reactive oxygen species (ROS) and secondary protein and DNA oxidation, microglial activation and astrocytosis. Brain small vessels exhibited decreased levels of endothelial NO synthase (eNOS), enlarged perivascular spaces with blood brain barrier (BBB) leak and decreased levels of tight-junction proteins. In the brain, amyloid-β deposition and phosphorylated-tau were detected with increases out to 60 weeks, at which time mice exhibited impaired spatial learning and memory. Thus, long-term CSE initiates a cascade of ROS generation and oxidative damage, eNOS dysfunction with cerebral hypoperfusion, as well as cerebrovascular and BBB damage with intracerebral inflammation, and neuronal degeneration, followed by the onset of impaired cognition and memory.

Palladium–reduced graphene oxide nanocomposites enhance neurite outgrowth and protect neurons from Ishemic stroke

Currently, the construction of novel biomimetic reduced graphene oxide (RGO)-based nanocomposites to induce neurite sprouting and repair the injured neurons represents a promising strategy in promoting neuronal development or treatment of cerebral anoxia or ischemia. Here, we present an effective method for constructing palladium-reduced graphene oxide (Pd-RGO) nanocomposites by covalently bonding Pd onto RGO surfaces to enhance neurite sprouting of cultured neurons. As described, the Pd-RGO nanocomposites exhibit the required physicochemical features for better biocompatibility without impacting cell viability. Primary neurons cultured on Pd-RGO nanocomposites had significantly increased number and length of neuronal processes, including both axons and dendrites, compared with the control. Western blotting showed that Pd-RGO nanocomposites improved the expression levels of growth associate protein-43 (GAP-43), as well as β-III tubulin, Tau-1, microtubule-associated protein-2 (MAP2), four proteins that are involved in regulating neurite sprouting and outgrowth. Importantly, Pd-RGO significantly promoted neurite length and complexity under oxygen-glucose deprivation/re-oxygenation (OGD/R) conditions, an in vitro cellular model of ischemic brain damage, that closely relates to neuronal GAP-43 expression. Furthermore, using the middle cerebral artery occlusion (MCAO) model in rats, we found Pd-RGO effectively reduced the infarct area, decreased neuronal apoptosis in the brain, and improved the rats’ behavioral outcomes after MCAO. Together, these results indicate the great potential of Pd-RGO nanocomposites as a novel excellent biomimetic material for neural interfacing that shed light on its applications in brain injuries.

Prevalence of Pulmonary Hypertension During Therapeutic Hypothermia for Hypoxic Ischemic Encephalopathy and Evaluation of Short-Term Outcomes.

Infants with perinatal asphyxia and moderate-to-severe hypoxic ischemic encephalopathy (HIE) are currently treated with therapeutic hypothermia (TH) as part of a brain protective strategy. However, perinatal asphyxia is a risk factor for development of persistent pulmonary hypertension (PPHN). As such, the aim of this study was to quantify the risk of PPHN in infants undergoing TH and assess short-term outcomes in infants developing PPHN. All N = 59 infants undergoing TH for moderate-to-severe HIE over a period of 3 years (January 2020-December 2022) at a single center were included. PPHN was diagnosed in N = 10 (17%), with this deemed to have been exacerbated by TH in n = 6 (10%). Only 50% (5/10) with PPHN required inhaled nitric oxide, and none of the infants received extracorporeal membrane oxygenation. PPHN was not found to be significantly associated with short-term outcomes, including the extent of HIE on brain magnetic resonance imagings, in-hospital mortality or requirement for nasogastric feeding at discharge. In conclusion, TH appears to be a safe and effective treatment for moderate-to-severe HIE with or without PPHN.

Improving the future of clinical trials and translation of mesenchymal stromal cell therapies for neonatal disorders.

Despite recent advances in neonatal intensive care medicine, neonatal disorders such as (bronchopulmonary dysplasia [BPD], intraventricular hemorrhage [IVH], and hypoxic ischemic encephalopathy [HIE]) remain major causes of death and morbidity in survivors, with few effective treatments being available. Recent preclinical studies have demonstrated the pleiotropic host injury-responsive paracrine protective effects of cell therapy especially with mesenchymal stromal cells (MSCs) against BPD, IVH, and HIE. These findings suggest that MSCs therapy might emerge as a novel therapeutic modality for these currently devastating neonatal disorders with complex multifactorial etiologies. Although early-phase clinical trials suggest their safety and feasibility, their clinical therapeutic benefits have not yet been proven. Therefore, based on currently available preclinical research and clinical trial data, we focus on critical issues that need to be addressed for future successful clinical trials and eventual clinical translation such as selecting the right patient and optimal cell type, route, dose, and timing of MSCs therapy for neonatal disorders such as BPD, HIE, and IVH.

Neuroprognostication, withdrawal of care and long-term outcomes after cardiopulmonary resuscitation.

Survivors of cardiac arrest often have increased long-term risks of mortality and disability that are primarily associated with hypoxic-ischemic brain injury (HIBI). This review aims to examine health-related long-term outcomes after cardiac arrest. A notable portion of cardiac arrest survivors face a decline in their quality of life, encountering persistent physical, cognitive, and mental health challenges emerging years after the initial event. Within the first-year postarrest, survivors are at elevated risk for stroke, epilepsy, and psychiatric conditions, along with a heightened susceptibility to developing dementia. Addressing these challenges necessitates establishing comprehensive, multidisciplinary care systems tailored to the needs of these individuals. HIBI remains the leading cause of disability among cardiac arrest survivors. No single strategy is likely to improve long term outcomes after cardiac arrest. A multimodal neuroprognostication approach (clinical examination, imaging, neurophysiology, and biomarkers) is recommended by guidelines, but fails to predict long-term outcomes. Cardiac arrest survivors often experience long-term disabilities that negatively impact their quality of life. The likelihood of such outcomes implements a multidisciplinary care an integral part of long-term recovery.

Cooling during transportation of newborns with hypoxic ischemic encephalopathy using phase change material mattresses in low-resource settings: a randomized controlled trial in Hanoi, Vietnam

ObjectiveTo determine the effectiveness of phase-change-material mattress (PCM) during transportation of newborns with hypoxic ischemic encephalopathy (HIE).Study designRandomized controlled trial of newborns with HIE from June 2016 to December 2019. Patients were randomized to transport with PCM or without PCM (control) when transferred to a cooling center in northern Vietnam. Primary outcome measure was mortality rate, secondary outcomes including temperature control and adverse effects.ResultFifty-Two patients in PCM-group and 61 in control group. Median rectal temperature upon arrival was 34.5 °C (IQR 33.5–34.8) in PCM-group and 35.1 °C (IQR 34.5–35.9) in control group (p = 0.023). Median time from birth to reach target temperature was 5.0 ± 1.4 h and 5.5 ± 1.2 h in the respective groups (p = 0.065). 81% of those transported with PCM versus 62% of infants transported without (p = 0.049) had reached target temperature within the 6-h timeframe. There was no record of overcooling (< 32 °C) in any of the groups. The was no difference in mortality rate between the two groups (33% and 34% respectively (p > 0.05)).ConclusionPhase-change-material can be used as a safe and effective cooling method during transportation of newborns with HIE in low-resource settings.Trial registrationThe study was retro-prospectively registered in Clinical Trials (04/05/2022, NCT05361473).

Diagnostic Markers of Pediatric Hypoxic–Ischemic Encephalopathy: A Systematic Review and Guide for Pediatricians and Nurses

Diagnostic Markers of Pediatric Hypoxic–Ischemic Encephalopathy: A Systematic Review and Guide for Pediatricians and Nurses

Thyroid hormone T3 induces Fyn modification and modulates palmitoyltransferase gene expression through αvβ3 integrin receptor in PC12 cells during hypoxia.

Thyroid hormones (THs) are essential in neuronal and glial cell development and differentiation, synaptogenesis, and myelin sheath formation. In addition to nuclear receptors, TH acts through αvβ3-integrin on the plasma membrane, influencing transcriptional regulation of signaling proteins that, in turn, affect adhesion and survival of nerve cells in various neurologic disorders. TH exhibits protective properties during brain hypoxia; however, precise intracellular mechanisms responsible for the preventive effects of TH remain unclear. In this study, we investigated the impact of TH on integrin αvβ3-dependent downstream systems in normoxic and hypoxic conditions of pheochromocytoma PC12 cells. Our findings reveal that triiodothyronine (T3), acting through αvβ3-integrin, induces activation of the JAK2/STAT5 pathway and suppression of the SHP2 in hypoxic PC12 cells. This activation correlates with the downregulation of the expression palmitoyltransferase-ZDHHC2 and ZDHHC9 genes, leading to a subsequent decrease in palmitoylation and phosphorylation of Fyn tyrosine kinase. We propose that these changes may occur due to STAT5-dependent epigenetic silencing of the palmitoyltransferase gene, which in turn reduces palmitoylation/phosphorylation of Fyn with a subsequent increase in the survival of cells. In summary, our study provides the first evidence demonstrating the involvement of integrin-dependent JAK/STAT pathway, SHP2 suppression, and altered post-translational modification of Fyn in protective effects of T3 during hypoxia.

Mechanisms of mitophagy and oxidative stress in cerebral ischemia-reperfusion, vascular dementia, and Alzheimer's disease.

Neurological diseases have consistently represented a significant challenge in both clinical treatment and scientific research. As research has progressed, the significance of mitochondria in the pathogenesis and progression of neurological diseases has become increasingly prominent. Mitochondria serve not only as a source of energy, but also as regulators of cellular growth and death. Both oxidative stress and mitophagy are intimately associated with mitochondria, and there is mounting evidence that mitophagy and oxidative stress exert a pivotal regulatory influence on the pathogenesis of neurological diseases. In recent years, there has been a notable rise in the prevalence of cerebral ischemia/reperfusion injury (CI/RI), vascular dementia (VaD), and Alzheimer's disease (AD), which collectively represent a significant public health concern. Reduced levels of mitophagy have been observed in CI/RI, VaD and AD. The improvement of associated pathology has been demonstrated through the increase of mitophagy levels. CI/RI results in cerebral tissue ischemia and hypoxia, which causes oxidative stress, disruption of the blood-brain barrier (BBB) and damage to the cerebral vasculature. The BBB disruption and cerebral vascular injury may induce or exacerbate VaD to some extent. In addition, inadequate cerebral perfusion due to vascular injury or altered function may exacerbate the accumulation of amyloid β (Aβ) thereby contributing to or exacerbating AD pathology. Intravenous tissue plasminogen activator (tPA; alteplase) and endovascular thrombectomy are effective treatments for stroke. However, there is a narrow window of opportunity for the administration of tPA and thrombectomy, which results in a markedly elevated incidence of disability among patients with CI/RI. It is regrettable that there are currently no there are still no specific drugs for VaD and AD. Despite the availability of the U.S. Food and Drug Administration (FDA)-approved clinical first-line drugs for AD, including memantine, donepezil hydrochloride, and galantamine, these agents do not fundamentally block the pathological process of AD. In this paper, we undertake a review of the mechanisms of mitophagy and oxidative stress in neurological disorders, a summary of the clinical trials conducted in recent years, and a proposal for a new strategy for targeted treatment of neurological disorders based on both mitophagy and oxidative stress.

Burst-Suppression EEG Reactivity to Photic Stimulation-A Translational Biomarker in Hypoxic-Ischemic Brain Injury.

The reactivity of an electroencephalogram (EEG) to external stimuli is impaired in comatose patients showing burst-suppression (BS) patterns following hypoxic-ischemic brain injury (HIBI). We explored the reactivity of BS induced by isoflurane in rat models of HIBI and controls using intermittent photic stimulation (IPS) delivered to one eye. The relative time spent in suppression referred to as the suppression ratio (SR) was measured on the contralateral fronto-occipital cortical EEG channel. The BS reactivity (BSR) was defined as the decrease in the SR during IPS from the baseline before stimulation (SRPRE). We found that BSR increased with SRPRE. To standardize by anesthetic depth, we derived the BSR index (BSRi) as BSR divided by SRPRE. We found that the BSRi was decreased at 3 days after transient global cerebral ischemia in rats, which is a model of brain injury after cardiac arrest. The BSRi was also reduced 2 months after experimental perinatal asphyxia in rats, a model of birth asphyxia, which is a frequent neonatal complication in humans. Furthermore, Oxytocin attenuated BSRi impairment, consistent with a neuroprotective effect in this model. Our data suggest that the BSRi is a promising translational marker in HIBI which should be considered in future neuroprotection studies.