Hypoxic-ischemic brain damage (HIBD) is one of the main causes of disability in middle-aged and elderly people, as well as high mortality rates and long-term physical impairments in newborns. The pathological manifestations of HIBD include neuronal damage and loss of myelin sheaths. Tau protein is an important microtubule-associated protein in brain, exists in neurons and oligodendrocytes, and regulates various cellular activities such as cell differentiation and maturation, axonal transport, and maintenance of cellular cytoskeleton structure. Phosphorylation is a common chemical modification of Tau. In physiological condition, it maintains normal cell cytoskeleton and biological functions by regulating Tau structure and function. In pathological conditions, it leads to abnormal Tau phosphorylation and influences its structure and functions, resulting in Tauopathies. Studies have shown that brain hypoxia-ischemia could cause abnormal alteration in Tau phosphorylation, then participating in the pathological process of HIBD. Meanwhile, brain hypoxia-ischemia can induce oxidative stress and inflammation, and multiple Tau protein kinases are activated and involved in Tau abnormal phosphorylation. Therefore, exploring specific molecular mechanisms by which HIBD activates Tau protein kinases, and elucidating their relationship with abnormal Tau phosphorylation are crucial for future researches on HIBD related treatments. This review aims to focus on the mechanisms of the role of Tau phosphorylation in HIBD, and the potential relationships between Tau protein kinases and Tau phosphorylation, providing a basis for intervention and treatment of HIBD.
Humans ; tau Proteins/physiology* ; Phosphorylation ; Hypoxia-Ischemia, Brain/physiopathology* ; Animals ; Oxidative Stress

OBJECTIVES: To evaluate the effect of eye acupuncture on neural function and angiogenesis of ischemic cerebral tissue in rats, and explore the roles of METTL3-mediated m⁶A methylation and the HIF-1α/VEGF-A signal axis in mediating this effect. METHODS: Fifty SD rats were randomized into normal control group, sham-operated group, model group, eye acupuncture group and DMOG (a HIF-1α agonist) group. Rat models of cerebral ischemia/reperfusion injury (CIRI) were established using a modified thread thrombus method, and the changes in neurological deficits of the rats after interventions were evaluated. TTC and Nissl staining were used to examine the changes in infarction size and neuronal injury, and cerebral angiogenesis was detected by double-immunofluorescence staining. m⁶A methylation modification level in the brain tissue was detected by ELISA, and RT-qPCR and Western blotting were used to detect the mRNA and protein expressions of METTL3 and HIF-1α/VEGF-A. RESULTS: Compared with the control and sham-operated rats, the CIRI rats had significantly higher neurological deficit scores with larger cerebral infarction area, a greater number of CD31- and EDU-positive new vessels, higher expression levels of HIF-1α and VEGF-A, reduced number of Nissl bodies and m6A methylation level, and lowered METTL3 protein and mRNA expressions. All these changes were significantly improved by interventions with eye acupuncture after modeling or intraperitoneal injections of DMOG for 7 consecutive days prior to modeling, and the effects of the two interventions were similar. CONCLUSIONS Eye acupuncture can improve neurological deficits in CIRI rat models possibly by promoting cortical angiogenesis via upregulating METTL3-mediated m⁶A methylation and regulating the HIF-1α/VEGF-A signal axis.
Animals ; Rats, Sprague-Dawley ; Methyltransferases/metabolism* ; Reperfusion Injury/physiopathology* ; Methylation ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Rats ; Vascular Endothelial Growth Factor A/metabolism* ; Brain Ischemia/metabolism* ; Acupuncture Therapy ; Male ; Up-Regulation ; Neovascularization, Physiologic ; Angiogenesis ; Adenosine/analogs & derivatives*

OBJECTIVE: To approach the evaluation of relative α variant score monitored by bedside continuous electroencephalography and optic nerve sheath diameter (ONSD) evaluated by ultrasound in patients with ischemic hypoxic encephalopathy, and to observe the effect of neurofeedback training on brain function. METHODS: A prospective observational study was conducted. The patients admitted to the emergency and intensive care department of Shanghai Pudong New Area People's Hospital from January 2021 to December 2023, who meet the diagnostic criteria of ischemic hypoxic encephalopathy with the Glasgow coma score (GCS) ≤ 8 at admission receiving neurofeedback training were enrolled as the study object (observation group), and the patients without neurofeedback training and GCS score ≤ 8 at admission were enrolled as the controls (control group). Both groups received intravenous neurotrophic therapy combining ganglioside and cerebrolysin for 10 days as one course of treatment. On this basis, the observation group additionally received continuous neurofeedback training including visual feedback, auditory feedback, meditation and relaxation for 14 days. Bedside continuous electroencephalography was used for monitoring relative α variation score, and ultrasound was used to determine ONSD. The average power and slow wave power [expressed as delta-theta ratio (DTR)] of five channels in electroencephalography before and 14 days after neurofeedback training were examined. The differences in peripheral blood neutrophil/lymphocyte ratio (NLR), Hamilton depression scale (HAMD) score, National Institutes of Health stroke scale (NIHSS) score, plasma levels of 5-hydroxytryptamine (5-HT) and brain-derived neurotrophic factor (BDNF). RESULTS: A total of 60 patients were enrolled in the observation group and 50 patients in the control group finally. There was no significant difference in gender, age or course of disease between the two groups. The ONSD and relative α variant score in the observation group were significantly higher than those in the control group [ONDS (mm): 5.59±0.42 vs. 3.23±0.34, relative α variant score: 2.28±0.39 vs. 0.83±0.28, both P < 0.01]. After neurofeedback training for 14 days, the mean power and DTR in five channels of electroencephalography in the observation group were significantly lower than those before treatment [mean power (μV²/Hz): 95.35±3.61 vs. 102.58±4.23 in frontal pole 1 (Fp1), 38.56±4.73 vs. 46.13±2.36 in frontal 3 (F3), 34.33±5.87 vs. 51.71±4.65 in central 3 (C3), 58.37±4.45 vs. 62.95±3.22 in F7, 45.23±2.41 vs. 54.14±2.45 in temporal 3 (T3); DTR (μV²/Hz): 75.21±11.34 vs. 84.12±11.35 in ground electrode (GND), 72.31±21.67 vs. 88.23±10.25 in reference electrode (REF), 81.34±8.57 vs. 92.41±8.56 in F4, 71.25±5.42 vs. 87.23±5.64 in parietal 3 (P3), 70.12±5.88 vs. 85.67±6.12 in P4; all P < 0.05]. However, there was no significant difference in the mean power of five channels before and after treatment in the control group. There was no significant difference in the HAMD score or NIHSS score before treatment between the two groups. The above scores at 14 days after treatment were significantly lower than before, and the decrease was more significant in the observation group (HAMD score: 4.59±1.06 vs. 10.69±0.97, NIHSS score: 6.81±0.66 vs. 8.45±0.87, both P < 0.01). There was no significant difference in the plasma 5-HT, BDNF or peripheral blood NLR before treatment between the two groups. The above parameters at 14 days after treatment were improved as compared with before, and the levels in the observation group were superior to control group [5-HT (mg/L): 150.25±17.37 vs. 123.34±16.18, BDNF (mg/L): 19.37±2.35 vs. 12.48±2.18, NLR: 4.78±0.83 vs. 5.81±1.17, all P < 0.01]. CONCLUSIONS Both ONDS determined by ultrasound and relative α variation score monitored by electroencephalography changed significantly in the patients with ischemic hypoxic encephalopathy. Neurofeedback training can effectively improve brain function in patients with ischemic hypoxic encephalopathy.
Humans ; Electroencephalography ; Prospective Studies ; Neurofeedback ; Optic Nerve/diagnostic imaging* ; Ultrasonography ; Hypoxia-Ischemia, Brain/physiopathology* ; Male ; Female ; Middle Aged

A 68-year-old man presented with a three-week history of rapidly progressive dementia, gait ataxia and myoclonus. Subsequent electroencephalography showed periodic sharp wave complexes, and cerebrospinal fluid assay revealed the presence of a 14-3-3 protein. A probable diagnosis of sporadic Creutzfeldt-Jakob disease was made, which was further supported by magnetic resonance (MR) imaging of the brain showing asymmetric signal abnormality in the cerebral cortices and basal ganglia. The aetiology, clinical features, diagnostic criteria, various MR imaging patterns and radiologic differential diagnosis of sporadic Creutzfeldt-Jakob disease are discussed in this article.
Aged ; Brain ; pathology ; Cerebral Cortex ; Cerebrospinal Fluid ; metabolism ; Creutzfeldt-Jakob Syndrome ; diagnostic imaging ; Dementia ; physiopathology ; Diagnosis, Differential ; Diffusion Magnetic Resonance Imaging ; Electroencephalography ; Humans ; Hypoxia-Ischemia, Brain ; diagnostic imaging ; Male ; Prion Diseases ; physiopathology

OBJECTIVETo investigate mitophagy in an animal model of hypoxic-ischemic brain damage (HIBD) and its role in HIBD.

METHODSA total of 120 neonatal Sprague-Dawley rats aged 7 days were divided into three groups: sham-operation, HIBD, and autophagy inhibitor intervention (3MA group). The rats in the HIBD group were treated with right common carotid artery ligation and then put in a hypoxic chamber (8% oxygen and 92% nitrogen) for 2.5 hours. Those in the 3MA group were given ligation and hypoxic treatment at 30 minutes after intraperitoneal injection of 2 μL 3MA. Those in the sham-operation group were not given ligation or hypoxic treatment. Single cell suspension was obtained from all groups after model establishment. Immunofluorescence localization was performed for mitochondria labeled with MitoTracker, autophagosomes labeled with LysoTracker, and autophagy labeled with LC3 to observe mitophagy. After staining with the fluorescent probe JC-1, flow cytometry was used to measure mitochondrial membrane potential. TTC staining was used to measure infarct volume. Cytoplasmic proteins in cortical neurons were extracted, and Western blot was used to measure the expression of mitophagy-related proteins.

RESULTSCompared with the sham-operation group, the HIBD group had a significant reduction in mitochondrial membrane potential (P<0.05), a significant increase in mitophagy (P<0.05), a significant increase in the expression of the proteins associated with the division of the mitochondrial Drp1 and Fis1 (P<0.05), and a significant reduction in the expression of the mitochondrial outer membrane protein Tom20 and the mitochondrial inner membrane protein Tim23 (P<0.05). Compared with the HIBD group, the 3MA group had a significantly greater reduction in mitochondrial membrane potential (P<0.05), but showed significantly reduced mitophagy (P<0.05). In addition, the 3MA group had a significantly increased degree of cerebral infarction compared with the HIBD group (P<0.05).

CONCLUSIONSHIBD can increase the degree of mitophagy, and the inhibition of mitophagy can aggravate HIBD in neonatal rats.

Animals ; Animals, Newborn ; Female ; Hypoxia-Ischemia, Brain ; etiology ; physiopathology ; Male ; Mitochondrial Degradation ; physiology ; Rats ; Rats, Sprague-Dawley

Autophagy is a highly evolutionarily conserved physiological mechanism of organism, including several stages such as autophagosomes formation, the fusion of lysosomes and autophagosomes, and autophagosomes degradation. In physiological conditions, autophagy is responsible for clearing the spoiled organelles and long-lived proteins to maintain the homeostasis of cells and organism. Meanwhile, autophagy is also involved in the formation and development of diseases, but the mechanism has not been confirmed yet. The relationship between autophagy and hypoxic ischemic brain injuries represented by stroke is a research hotpot in recent years, but there is no clear conclusion about autophagy's role and mechanism in hypoxic ischemic brain injuries. We reviewed the activation, function and mechanism of autophagy in hypoxic ischemic brain injuries, in order to provide some perspectives on these researches.
Animals ; Autophagy ; Homeostasis ; Humans ; Hypoxia-Ischemia, Brain ; physiopathology ; Lysosomes

OBJECTIVETo explore the impacts of erythropoietin on vascular endothelial growth factor receptor 2 (VEGFR2) by the extracellular signal-regulated kinase (ERK) signaling pathway in a neonatal rat model of periventricular white matter damage.

METHODSAll of postnatal day 4 rats were randomized into three groups: the sham group [without hypoxia-ischemia (HI)], the HI group (HI with saline administration), and the erythropoietin (EPO) group [HI with recombinant human erythropoietin (rh-EPO) administration]. Rat pups underwent permanent ligation of the right common carotid artery, followed by 6% O2 for 2 hours or sham operation and normoxic exposure. Immediately after the HI, rats received a single intraventricular injection of rh-EPO (0.6 IU/g body mass) or saline. ERK and phosphorylation-ERK were examined at 60 minutes and 90 minutes after operation, and VEGFR2 were detected at 2 and 4 days after operation by using Western blot.

RESULTSAt 60 minutes and 90 minutes after operation, the proteins of phosphorylation-ERK were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05). Two days after operation, VEGFR2 was not significantly different between sham and HI rats. However, the proteins of VEGFR2 were increased after administration of rh-EPO (P<0.05). Four days after operation, the proteins of VEGFR2 were significantly higher in HI rats than in the sham rats and significantly higher in HI+EPO rats than in the HI rats (P<0.05).

CONCLUSIONEPO may regulate VEGFR2 expression by affecting the intracranial ERK signaling pathways.

Animals ; Animals, Newborn ; Disease Models, Animal ; Erythropoietin ; pharmacology ; Humans ; Hypoxia-Ischemia, Brain ; physiopathology ; MAP Kinase Signaling System ; Phosphorylation ; Rats ; Rats, Sprague-Dawley ; Recombinant Proteins ; pharmacology ; Vascular Endothelial Growth Factor Receptor-2 ; metabolism ; White Matter ; physiopathology

OBJECTIVETo study the changes of miRNA expression in the pineal gland of neonatal rats with hypoxic-ischemic brain damage (HIBD) and the possible roles of miRNA in the pathogenesis of circadian rhythm disturbance after HIBD.

METHODSSeven-day-old Sprague-Dawley (SD) rats were randomly divided into 2 groups: HIBD and sham-operated. HIBD was induced according to the Rice-Vannucci method. The pineal glands were obtained 24 hours after the HIBD event. The expression profiles of miRNAs were determined using GeneChip technigue and quantitative real-time PCR (RT-PCR). Then the miRNA which was highly expressed was selected. The expression levels of the chosen miRNA were detected in different tissues (lungs, intestines, stomach, kidneys, cerebral cortex, pineal gland). RT-PCR analysis was performed to measure the expression profiles of the chosen miRNA and the targeted gene Clock mRNA in the pineal gland at 0, 24, 48 and 72 hours after HIBD.

RESULTSmiRNA-182 that met the criteria was selected by GeneChip and RT-PCR. miRNA-182 was highly expressed in the pineal gland. Compared with the sham-operated group, the expression of miRNA-182 was significantly up-regulated in the pineal gland at 24 and 48 hours after HIBD (P<0.05). Compared with the sham-operated group, Clock mRNA expression in the HIBD group increased at 0 hour after HIBD, decreased at 48 hours after HIBD and increased at 72 hours after HIBD (P<0.05).

CONCLUSIONSmiRNA-182 may be involved in the pathogenesis of circadian rhythm disturbance after HIBD.

Animals ; Animals, Newborn ; CLOCK Proteins ; genetics ; Circadian Rhythm ; physiology ; Female ; Gene Expression Regulation ; Hypoxia-Ischemia, Brain ; physiopathology ; Male ; MicroRNAs ; analysis ; physiology ; Pineal Gland ; metabolism ; RNA, Messenger ; analysis ; Rats ; Rats, Sprague-Dawley ; Real-Time Polymerase Chain Reaction

Hypoxic-ischemic brain damage (HIBD) is referred to a common type of cerebral damage, which is caused by injury, leading to shallow bleeding in the cortex with intact cerebral pia mater. In recent years, studies show that a various kinds of immune cells and immune cellular factors are involved in the occurrence of HIBD. CC chemokine receptor 2 (CCR2) is a representative of CC chemokine receptor, and is widely distributed in cerebral neuron, astrocyte, and microglial cells, and is the main chemo-tactic factor receptor in brain tissue. CC chemokine ligand 2 (CCL2) is a kind of basophilic protein and the ligand of CCR2, and plays an important role in inflammation. In order to provide evidence for correlational studies in HIBD, this review will introduce the biological characteristics of CCR2 and CCL2, and illustrate the relationship between the immunoreactivity and HIBD.
Animals ; Brain Injuries/pathology* ; Cerebral Cortex/physiopathology* ; Chemokine CCL2/metabolism* ; Chemokines, CC/metabolism* ; Hypoxia-Ischemia, Brain/metabolism* ; Macrophage Inflammatory Proteins/metabolism* ; RNA, Messenger/metabolism* ; Rats ; Rats, Sprague-Dawley ; Receptors, CCR2/metabolism*

Carbon monoxide intoxication is the most prevalent cause of death from carbon monoxide poisoning. We herein report the case of a 56-year-old man who was found unconscious and smelled of smoke after exposure to carbon monoxide from a heater. He scored 5 on the Glasgow Coma Scale, and had respiratory insufficiency and elevated troponin I, creatine kinase-MB fraction and carboxyhaemoglobin levels. He was treated by mechanical ventilation. After regaining consciousness, brain magnetic resonance imaging showed diffusion restriction in the left occipital lobe; there was a loss of vision (right temporal hemianopsia), which improved by the follow-up session. Carbon monoxide intoxication may cause neurologic and cardiac sequelae, and the initial treatment includes oxygen therapy. Acute carbon monoxide poisoning can cause serious injury to the brain, heart and other organs; the most severe damages that could be inflicted to the brain include cerebral ischaemia and hypoxia, oedema, and neural cell degeneration and necrosis.
Brain ; physiopathology ; Brain Ischemia ; physiopathology ; Carbon Monoxide ; chemistry ; Carbon Monoxide Poisoning ; physiopathology ; Carboxyhemoglobin ; chemistry ; Creatine Kinase, MB Form ; blood ; Diffusion ; Glasgow Coma Scale ; Humans ; Hyperbaric Oxygenation ; Hypoxia ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Myocardial Ischemia ; physiopathology ; Stroke ; physiopathology ; Troponin I ; blood