Hypoxic-ischemic Encephalopathy Rat Research Articles

Evaluation of syringin's neuroprotective effect in a model of neonatal hypoxic-ischemic brain injury.

A significant cause of mortality and morbidity in the neonatal era is hypoxic-ischemic encephalopathy (HIE). This study examined the histopathological analysis and neuroprotective impact of syringin (SYR) in an experimental HIE rat model. On the 7th postnatal day, 24 Wistar albino rats were evaluated in 3 groups using the HIE model under gas anesthesia. In the experiment, Group A received 10 mg/kg SYR plus dimethyl sulfoxide (DMSO), Group B received DMSO only, and Group C served as a sham group. Immunohistochemical techniques were used to assess apoptotic cell measurement and proinflammatory cytokines (TNF-α and IL-1β primary antibodies). Rats suffering from hypoxic-ischemic brain damage had their apoptosis assessed. The SYR and sham groups had statistically fewer cells undergoing apoptosis (p < 0.001). There was no difference between the groups in terms of IL-1β and TNF-α during immunohistochemical staining. Neuronal degeneration was significantly lower in the histological evaluation of the hippocampus in the SYR group (p = 0.01). A statistically significant difference (p = 0.01) was observed between the SYR and the control groups regarding pericellular and perivascular edema. SYR reduced apoptosis, perivascular and pericellular edema, and neuronal degeneration in rat cerebral tissue. These results raise the possibility that SYR may have a neuroprotective effect on the harm brought on by HIE. This is the first investigation of SYR's function within the HIE paradigm.

Early Neuroprotective Effects of Bovine Lactoferrin Associated with Hypothermia after Neonatal Brain Hypoxia-Ischemia in Rats.

Neonatal hypoxic-ischemic (HI) encephalopathy (HIE) in term newborns is a leading cause of mortality and chronic disability. Hypothermia (HT) is the only clinically available therapeutic intervention; however, its neuroprotective effects are limited. Lactoferrin (LF) is the major whey protein in milk presenting iron-binding, anti-inflammatory and anti-apoptotic properties and has been shown to protect very immature brains against HI damage. We hypothesized that combining early oral administration of LF with whole body hypothermia could enhance neuroprotection in a HIE rat model. Pregnant Wistar rats were fed an LF-supplemented diet (1 mg/kg) or a control diet from (P6). At P7, the male and female pups had the right common carotid artery occluded followed by hypoxia (8% O2 for 60') (HI). Immediately after hypoxia, hypothermia (target temperature of 32.5-33.5 °C) was performed (5 h duration) using Criticool®. The animals were divided according to diet, injury and thermal condition. At P8 (24 h after HI), the brain neurochemical profile was assessed using magnetic resonance spectroscopy (1H-MRS) and a hyperintense T2W signal was used to measure the brain lesions. The mRNA levels of the genes related to glutamatergic excitotoxicity, energy metabolism and inflammation were assessed in the right hippocampus. The cell markers and apoptosis expression were assessed using immunofluorescence in the right hippocampus. HI decreased the energy metabolites and increased lactate. The neuronal-astrocytic coupling impairments observed in the HI groups were reversed mainly by HT. LF had an important effect on astrocyte function, decreasing the levels of the genes related to glutamatergic excitotoxicity and restoring the mRNA levels of the genes related to metabolic support. When combined, LF and HT presented a synergistic effect and prevented lactate accumulation, decreased inflammation and reduced brain damage, pointing out the benefits of combining these therapies. Overall, we showed that through distinct mechanisms lactoferrin can enhance neuroprotection induced by HT following neonatal brain hypoxia-ischemia.

Multi-omics reveal neuroprotection of Acer truncatum Bunge Seed extract on hypoxic-ischemia encephalopathy rats under high-altitude

Hypoxic-ischemic encephalopathy (HIE) at high-altitudes leads to neonatal mortality and long-term neurological complications without effective treatment. Acer truncatum Bunge Seed extract (ASO) is reported to have effect on cognitive improvement, but its molecular mechanisms on HIE are unclear. In this study, ASO administration contributed to reduced neuronal cell edema and improved motor ability in HIE rats at a simulated 4500-meter altitude. Transcriptomics and WGCNA analysis showed genes associated with lipid biosynthesis, redox homeostasis, neuronal growth, and synaptic plasticity regulated in the ASO group. Targeted and untargeted-lipidomics revealed decreased free fatty acids and increased phospholipids with favorable ω-3/ω-6/ω-9 fatty acid ratios, as well as reduced oxidized glycerophospholipids (OxGPs) in the ASO group. Combining multi-omics analysis demonstrated FA to FA-CoA, phospholipids metabolism, and lipid peroxidation were regulated by ASO treatment. Our results illuminated preliminary metabolism mechanism of ASO ingesting in rats, implying ASO administration as potential intervention strategy for HIE under high-altitude.

TNF-α interference ameliorates brain damage in neonatal hypoxic-ischemic encephalopathy rats by regulating the expression of NT-3 and TRKC.

The aim of this study is to explore the effect of tumor necrosis factor-α (TNF-α) inhibition in rats with neonatal hypoxic-ischemic encephalopathy (HIE) and ascertain the relevant signaling pathways. The Zea-Longa score was used to evaluate the neurological function of the rats. ImageJ was used for quantification of the brain edema volume. Triphenyl tetrazolium chloride (TTC) staining of brain tissue was performed 24 h after hypoxic-ischemic (HI) to detect right brain infarction. The expression of TNF-α was detected by real-time quantitative polymerase chain reaction (RT-qPCR). Immunofluorescence staining was used to identify the localization of TNF-α; Then, the effective shRNA fragment of TNF-α was used to validate the role of TNF-α in HIE rats, and the change of neurotrofin-3 (NT-3) and tyrosine kinase receptor-C (TRKC) was examined after TNF-α-shRNA lentivirus transfection to determine downstream signaling associated with TNF-α. Protein interaction analysis was carried out to predict the links among TNF-α, NT-3, and TRKC. Cerebral edema volume and infarction increased in the right brain after the HI operation. The Zea-Longa score significantly increased within 24 h after the HI operation. The relative expression of TNF-α was upregulated afterthe HI operation. TNF-α was highly expressed in the right hippocampus post HI through immunofluorescence staining. Bioinformatics analysis found a direct or an indirect link among TNF-α, NT-3, and TRKC. Moreover, the interference of TNF-α increased the expression of NT-3 and TRKC.TNF-α interference might alleviate brain injury in HIE by upregulating NT-3 and TRKC.

Downregulation of TRIM27 alleviates hypoxic-ischemic encephalopathy through inhibiting inflammation and microglia cell activation by regulating STAT3/HMGB1 axis

TRIM27 expression was increased in the Parkinson's disease (PD), and knockdown of TRIM27 in PC12 cells significantly inhibited cell apoptosis, indicating that downregulation of TRIM27 exerts a neuroprotective effect. Herein, we investigated TRIM27 role in hypoxic-ischemic encephalopathy (HIE) and the underlying mechanisms. HIE models were constructed in newborn rats using hypoxic ischemic (HI) treatment and PC-12/BV2 cells with oxygen glucose deprivation (OGD), respectively. The results demonstrated that TRIM27 expression was increased in the brain tissues of HIE rats and OGD-treated PC-12/BV2 cells. Downregulation of TRIM27 reduced the brain infarct volume, inflammatory factor levels and brain injury, as well as decreased the number of M1 subtype of microglia cells while increased the number of M2 microglia cells. Moreover, deletion of TRIM27 expression inhibited the expression of p-STAT3, p-NF-κB and HMGB1 in vivo and in vitro. In addition, overexpression of HMGB1 impaired the effects of TRIM27 downregulation on improving OGD-induced cell viability, inhibiting inflammatory reactions and microglia activation. Collectively, this study revealed that TRIM27 was overexpressed in HIE, and downregulation of TRIM27 could alleviate HI-induced brain injury through repressing inflammation and microglia cell activation via the STAT3/HMGB1 axis.

N-acetylserotonin inhibits oxidized mitochondrial DNA-induced neuroinflammation by activating the AMPK/PGC-1α/TFAM pathway in neonatal hypoxic-ischemic brain injury model

Hypoxic-ischemic encephalopathy (HIE) is a substantial cause of irreversible nerve injury in newborns. As the endogenous precursor of melatonin, N-acetylserotonin (NAS) can cross the blood–brain barrier and exert neuroprotective effects. Evidence shows that NAS exerts a neuroprotective role in ischemic brain injury by inhibiting the mitochondrial death pathway. This study investigates whether NAS can play a neuroprotective role in the HIE model and explores its underlying molecular mechanism. In vivo, postnatal day 7 (P7) Sprague-Dawley rats were used to construct the HIE rat model. Significant improvement in short-term neurobehavioral impairment, cerebral infarction volume decrease, and neuronal injury mitigation was observed with NAS treatment after hypoxic-ischemic (HI) injury. In addition, we validated that NAS suppressed NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome activation and NLRP3 inflammasome-related protein expression in the HIE model. Furthermore, we demonstrate that NAS reduced mitochondrial membrane potential loss, oxidative damage to mitochondrial DNA (mtDNA), cytosolic mtDNA copy number and activation of its downstream cyclic guanosine monophosphate adenylate synthase (cGAS)/ stimulator of interferon genes (STING) pathway. Additionally, we further verified the activation of NAS on the AMP-activated protein kinase (AMPK)/ peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α)/ mitochondrial transcription factor A (TFAM) pathway and found that inhibition of AMPK could increase cytosolic mtDNA copy number and NLRP3 inflammasome-related protein expression while decreasing STING protein expression. Our study demonstrated that NAS inhibits oxidative mtDNA-induced neuroinflammation, which is partially associated with AMPK/PGC-1α/TFAM pathway activation in the HIE model.

Lipidomics reveal the cognitive improvement effects of Acer truncatum Bunge seed oil on hypoxic-ischemic encephalopathy rats.

Hypoxic-ischemic encephalopathy (HIE) is one of the leading causes of acute neonatal death and chronic neurological damage, and severe HIE can have secondary sequelae such as cognitive impairment and cerebral palsy, for which effective interventions are lacking. In this study, we found that continuous 30-day intake of Acer truncatum Bunge seed oil (ASO) reduced brain damage and improved cognitive ability in HIE rats. Using lipidomic strategies, we observed that HIE rats had decreased unsaturated fatty acids and increased lysophospholipids in the brain. However, after 30 days of ASO treatment, phospholipids, plasmalogens, and unsaturated fatty acids increased, while lysophospholipids and oxidized glycerophospholipids decreased in both serum and the brain. Enrichment analysis showed that ASO intake mainly affected sphingolipid metabolism, fat digestion and absorption, glycerolipid metabolism and glycerophospholipid metabolic pathways in serum and the brain. Cluster, correlation, and confirmatory factor analyses showed that cognitive improvement after ASO administration was attributed to increased essential phospholipids and ω3/6/9 fatty acids, coupled with decreased oxidized glycerophospholipids in HIE rats. Our findings indicate that ASO has the potential to be developed as an effective food supplement for ischemic hypoxic newborns.

Dr Cerebrolysin Improves Motor Abilities and Reverses the Long-Term Memory Acquisition Deficit in Rats with Hypoxic-Ischemic Encephalopathy

Background: Hypoxic-ischemic encephalopathy (HIE) is a neurological condition that leads to motor disabilities and even death in neonates. Unfortunately, few therapeutic alternatives can contribute to brain recovery after HIE damage. Cerebrolysin is a neuropeptide mixture that performs neuroprotective and neurotrophic effects on injured brain tissue after systemic administration. Aims: This study evaluates the effects of the Cerebrolysin intraperitoneal administration, Methods:10 mL/kg; once a day for 7 days, since postnatal day 8 (PD8) to PD14 on the neonatal neurobehavior in an HIE rat model was administrated. Results: Cerebrolysin administration after a hypoxic-ischemic insult minimized brain damage and increased cellular viability. Furthermore, this neuroprotective effect lasted until adulthood, improving some motor abnormalities and reversing the long-term memory acquisition deficit caused by HIE. Conclusion: Repeated Cerebrolysin administration can reduce HIE Motor Disabilities and Reverses the Long-Term Memory Acquisition Deficit in neonatal rats safely and effectively.

MiR-204-5p Inhibits the Proliferation and Differentiation of Fetal Neural Stem Cells by Targeting Wingless-Related MMTV Integration Site 2 to Regulate the Ephrin-A2/EphA7 Pathway

Neonatal hypoxic ischemic encephalopathy (HIE) is mainly resulted from perinatal asphyxia, which can be repaired by NSCs. miR-204-5p is claimed to impact the activity NSCs. Our research will probe the miR-204-5p function in oxygen-glucose deprivation (OGD)-treated NSCs. miR-204-5p level was enhanced and WNT2 level was reduced in HIE rats. Rat NSCs were stimulated with OGD condition under the managing of mimic or inhibitor of miR-204-5p. The declined cell viability, enhanced apoptosis, downregulated Tuj1 and GFAP levels, and shortened total neurite length were observed in OGD-treated NSCs, which were further aggravated by the mimic and rescued by the inhibitor of miR-204-5p. Furthermore, the inactivated WNT2 and Ephrin-A2/EphA7 signaling pathway in OGD-stimulated NSCs was further repressed by the mimic and rescued by the inhibitor of miR-204-5p. In addition, WNT2 was confirmed as the targeting of miR-204-5p. Lastly, the function of miR-204-5p mimic on the proliferation, apoptosis, differentiation, WNT2 and Ephrin-A2/EphA7 signaling pathway in OGD-stimulated NSCs was abolished by HLY78, an activator of Wnt signaling. Collectively, miR-204-5p repressed the growth and differentiation of fetal NSCs by targeting WNT2 to regulate the Ephrin-A2/EphA7 pathway.

Protective effect of isoflurane preconditioning on neurological function in rats with HIE.

Hypoxic-ischemic encephalopathy (HIE) is an important cause of neonatal death and disability, which can lead to long-term neurological and motor dysfunction. Currently, inhalation anesthetics are widely used in surgery, and some studies have found that isoflurane (ISO) may have a positive effect on neuroprotection. In this paper, we investigated whether ISO pretreatment has a neuroprotective effect on the neurological function of HIE rats. Here, 7-day-old neonatal rats were randomly divided into a sham group, a hypoxic-ischemic (HI) group, and an ISO pretreatment (pretreatment) group. The pretreatment group was pretreated with 2% ISO for 1 h, followed by the HI group to establish an HI animal model. The HI‑induced neurological injury was evaluated by Zea‑Longa scores and triphenyltetrazolium (TTC) staining. Neuronal number and histomorphological changes were observed with Nissl staining and Hematoxylin-eosin (HE) staining. In addition, motor learning memory function was evaluated by the Morris water maze (MWM), the Y-maze, and the rotarod tests. HI induced severe neurological dysfunction, brain infarction, and cell apoptosis as well as obvious neuron loss in neonatal rats. In the MWM, the rats in the pretreatment group showed a decrease in escape latency (p = 0.042), indicating that pretreatment with ISO could improve the learning ability of HI rats. The results of Nissl staining showed that in the HI group, there was an irregular arrangement of neurons and nuclear fixation; however, the cell damage was significantly reduced and the total number of neurons was increased after ISO pretreatment (p < 0.001). In conclusion, ISO pretreatment improved cognitive function and attenuated HI-induced reduction of Nissl-positive cells and spatial memory impairment, suggesting that pretreatment with ISO before HI modeling could reduce neuronal cell death in the hippocampus after HI.

Transcriptional regulation of NRF1 on metabotropic glutamate receptors in a neonatal hypoxic‑ischemic encephalopathy rat model.

Neonatal hypoxic-ischemic encephalopathy (HIE) is a kind of brain injury that causes severe neurological disorders in newborns. Metabotropic glutamate receptors (mGluRs) and ionotropic glutamate receptors (iGluRs) are significantly associated with HIE and are involved in ischemia-induced excitotoxicity. This study aimed to investigate the upstream mechanisms of mGluRs and the transcriptional regulation by nuclear respiratory factor 1 (NRF1). The rat model of neonatal HIE was created using unilateral carotid artery ligation and in vitro oxygen-glucose deprivation paradigm. We used western blot, immunofluorescence, Nissl staining, and Morris water maze to investigate the impact of NRF1 on brain damage and learning memory deficit by HIE. We performed ChIP and luciferase activities to identify the transcriptional regulation of NRF1 on mGluRs. The neuronal NRF1 and some glutamatergic genes expression synchronously declined in infarcted tissues. The NRF1 overexpression effectively restored the expression of some glutamatergic genes and improved cognitive performance. NRF1 regulated some members of mGluRs and iGluRs in hypoxic-ischemic neurons. Finally, NRF1 is bound to the promoter regions of Grm1, Grm2, and Grm8 to activate their transcription. NRF1 is involved in the pathology of the neonatal HIE rat model, suggesting a novel therapeutic approach to neonatal HIE. NRF1 and some glutamatergic genes were synchronously downregulated in the infarcted brain of the neonatal HIE rat model. NRF1 overexpression could rescue cognitive impairment caused by the neonatal HIE rat model. NRF1 regulated the expressions of Grm1, Grm2, and Grm8, which activated their transcription by binding to the promoter regions.

Increased Neuron Specific Enolase in a Hypoxic Ischemia Rat Model

Introduction: Acute brain injury caused by cerebral ischemia, either due to stroke or ischemic hypoxic-ischemic encephalopathy (HIE), represents a major neurological cause of death and disability worldwide. Neuronal cell injury has been shown to correlate with a significant increase in neuron-specific enolase (NSE) levels in in vitro studies. This study aims to measure NSE levels in the blood serum of rats with HIE. Methods: This study used an experimental post-test design in which occlusion of the right common carotid artery (CCA) was performed on Wistar rats, which were then placed in a hypoxic chamber and reperfused after 60 minutes (treatment group). Neurological scores were collected over the first 24 hours. After 48 hours, experimental animals were sacrificed and their serum NSE levels were measured using ELISA. Statistical analysis using a T-test was performed for independent samples. Results: A total of 16 male rats were included in the study. Neurological scores indicated that all HIE group rats experienced hemiparesis to varying degrees. NSE levels in the treatment group were significantly higher than in the control group (p &lt; 0.05). The mean NSE level in the treatment group was higher than that in the other group. Conclusion: Consistent with in vitro studies, we found that NSE was higher in the HIE rat model than in controls. These data support future studies to assess the fitness of serum NSE as a biomarker of brain damage.

The protective effect of MiR-27a on the neonatal hypoxic-ischemic encephalopathy by targeting FOXO1 in rats.

BackgroundNeonatal hypoxic-ischemic encephalopathy (HIE), a kind of hypoxic-ischemic brain damage caused by perinatal asphyxia, is the most crucial cause of neonatal death and long-term neurological dysfunction in children. We aimed to investigate the protective effects of micro (mi)R-27a on HIE in neonatal rats.MethodsA rat model of neonatal HIE was constructed by modification of the Rice-Vannucci model. Real-time quantitative polymerase chain reaction (RT-qPCR) was used to test the expressions of miR-27a, FOXO1 messenger RNA (mRNA), interleukin-1β (IL-1β) mRNA, and tumor necrosis factor-α (TNF-α) mRNA, and western blot was applied to test the expression of FOXO1. In order to overexpress miR-27a, an intracerebroventricular injection (i.c.v) of miR-27a mimic was administered. We adopted 2,3,5-triphenytetrazolium chloride (TTC) staining and brain water content measurement to test the effects of miR-27a on the infarcted volume and edema in brain after HIE. Flow cytometry (FCM) analysis was applied to test the effects of miR-27a on the infiltrated peripheral immune cells in the rat brains after HIE.ResultsWe successfully established a rat model of neonatal HIE. It was revealed that the expressions of miR-27a decreased gradually after HIE, however, the expressions of FOXO1 mRNA increased. After injection of the miR-27a mimic, the expression of miR-27a in the rat HIE model brains was significantly upregulated, however, the expression of FOXO1 was robustly downregulated. Both TTC staining and brain water content showed that the infarcted volume and brain edema was markedly increased after HIE. Interestingly, the overexpression of miR-27a reduced the infarcted volume and edema induced by HIE. Additionally, RT-qPCR and FCM analysis showed that HIE lead to increases of IL-1β, TNF-α, and infiltrated immune cells. Overexpression of miR-27a could reduce the expressions of IL-1β mRNA and TNF-α mRNA, and the cell numbers of infiltrated peripheral macrophages and neutrophils in the brain.ConclusionsMiR-27a plays protective roles by reducing infarct volume and brain edema, and inhibiting inflammatory factors and infiltrated peripheral immune cells by targeting FOXO1 in neonatal HIE rats.

The mechanism of sevoflurane post-treatment alleviating hypoxic-ischemic encephalopathy by affecting histone methyltransferase G9a in rats

ABSTRACT Hypoxic-ischemic encephalopathy (HIE) is recognized as the main cause of neonatal death, and efficient treatment strategies remain limited. This study aims to investigate the mechanism of sevoflurane (SF) post-treatment in alleviating HIE in rats. The HIE rat model and oxygen-glucose deprivation (OGD) cell model were established, and adeno-associated virus (AAV)-histone-lysine N-methyltransferase EHMT2 (G9a) was transfected after SF treatment. The learning and memory ability and the levels of nerve growth factor (NGF)/brain-derived neurotrophic factor (BDNF) were evaluated and determined. The levels of G9a/histone H3 lysine 9 dimethylation (H3K9me2) and the enrichment level of H3K9me2 in the promoter region of BDNF gene were analyzed. After SF post-treatment, the neurons in cerebral cortex, the learning and memory skills and the contents of NGF/BDNF were increased, while the apoptosis and G9a/H3K9me2 levels were reduced. After overexpression of G9a in vitro/vivo, the enrichment levels of H3K9me2 in the promoter region of BDNF were increased, the levels of BDNF were decreased, the neurons were damaged and the learning and memory abilities of HIE rats were impaired. The conclusion is that SF post-treatment can promote the expression of BDNF by inhibiting H3K9me2 on the BDNF gene promoter and inhibiting G9a, thus alleviating HIE in rats.

Classical complement pathway inhibition reduces brain damage in a hypoxic ischemic encephalopathy animal model.

Perinatal hypoxic ischemic encephalopathy (HIE) remains a major contributor of infant death and long-term disability worldwide. The role played by the complement system in this ischemia-reperfusion injury remains poorly understood. In order to better understand the role of complement activation and other modifiable mechanisms of injury in HIE, we tested the dual-targeting anti-inflammatory peptide, RLS-0071 in an animal model of HIE. Using the well-established HIE rat pup model we measured the effects of RLS-0071 during the acute stages of the brain injury and on long-term neurocognitive outcomes. Rat pups subject to hypoxia-ischemia insult received one of 4 interventions including normothermia, hypothermia and RLS-0071 with and without hypothermia. We measured histopathological effects, brain C1q levels and neuroimaging at day 1 and 21 after the injury. A subset of animals was followed into adolescence and evaluated for neurocognitive function. On histological evaluation, RLS-0071 showed neuronal protection in combination with hypothermia (P = 0.048) in addition to reducing C1q levels in the brain at 1hr (P = 0.01) and at 8 hr in combination with hypothermia (P = 0.005). MRI neuroimaging demonstrated that RLS-0071 in combination with hypothermia reduced lesion volume at 24 hours (P<0.05) as well as decreased T2 signal at day 21 in combination with hypothermia (P<0.01). RLS-0071 alone or in combination with hypothermia improved both short-term and long-term memory. These findings suggest that modulation by RLS-0071 can potentially decrease brain damage resulting from HIE.

Chinese Tuina Protects against Neonatal Hypoxia-Ischemia through Inhibiting the Neuroinflammatory Reaction.

Aim. Neonatal hypoxic-ischemic encephalopathy (HIE) is a significant cause of perinatal morbidity and mortality. Chinese Tuina is an effective treatment for HIE, but the molecular mechanisms are yet unknown. This study investigated the effect and mechanisms of Chinese Tuina on the inflammatory response in neonatal HIE rats. Main Methods. 30 male neonatal rats were divided randomly into 3 groups: sham, HIE, and HIE with Chinese Tuina (CHT) groups. The HIE and CHT groups were subjected to left common carotid occlusion and hypoxia at 3 days postnatal (P3). The pups in the CHT group received Chinese Tuina treatment on the next day for 28 days. The weight was measured at P4, P9, P13, P21, and P31. The behavioral functions were determined at P21. The protein expression and the methylation level in promoter regions of TNF-α and IL-10 were determined by Western blotting, immunohistochemistry, and pyrosequencing, respectively, at P33. Key Findings. The weight gain in the HIE group was slow compared with that of the CHT group. The rats in the CHT group performed better both in the balance beam and hang plate experiment. Chinese Tuina inhibited the expression of TNF-α and upregulated the expression of IL-10. Neonatal hypoxic-ischemic injury downregulated the methylation level in promoter regions of TNF-α at all CpG points but not IL-10. However, Chinese Tuina did not change the methylation level in promoter regions of TNF-α and IL-10. Significance. Chinese Tuina protected against HIE through inhibiting the neuroinflammatory reaction. While HIE markedly downregulated the methylation level of TNF-α, the protective effects of Chinese Tuina were independent of the regulation of the methylation level of TNF-α and IL-10.

N-acetylserotonin Derivative Exerts a Neuroprotective Effect by Inhibiting the NLRP3 Inflammasome and Activating the PI3K/Akt/Nrf2 Pathway in the Model of Hypoxic-Ischemic Brain Damage.

Neonatal hypoxic-ischemic encephalopathy (HIE) is one of the main causes of neonatal disability and death. As a derivative of N-acetylserotonin, N-[2-(5-hydroxy-1H-indol-3-yl) ethyl]-2-oxopiperidine-3-carboxamide (HIOC) can easily cross the blood-brain barrier and have a long half-life in the brain. In this study, the hypothesis was verified that HIOC plays a neuroprotective role in the HIE model and its potential mechanism was evaluated. Firstly, an HIE rat model was established to deliver HIOC, revealing that it can reduce cerebral infarction volume, cerebral edema, and neuronal apoptosis. The results of immunofluorescence staining, Western blots and RT-PCR further showed that HIOC could inhibit the activation of the NLRP3 inflammasome and the expression of related proteins. Finally, the activation of the phosphatidylinositol-3-kinase (PI3K)/Akt/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway by HIOC was verified in vitro and in vivo. It was discovered that HIOC could increase the nuclear translocation of Nrf2, and that this induction can be reversed by the PI3K/Akt pathway inhibitor LY294002. In general terms, the neuroprotective effect of HIOC was confirmed in the HIE model, which is related to the activation of the Pi3k/Akt/Nrf2 signal pathway and the inhibition of the NLRP3 inflammasome.

Mechanisms Underlying Abnormal Expression of lncRNA H19 in Neonatal Hypoxic-Ischemic Encephalopathy.

Hypoxic-ischemic (HI)-related brain injury, especially HI encephalopathy (HIE) is a leading cause of morbidity and disability in newborns. Long noncoding RNAs (lncRNAs) are implicated in the progress of HI brain damage. However, the mechanisms underlying the regulatory effects of lncRNA H19 on autophagy in HIE remain unknown. This study was designed to identify the potential mechanisms involving lncRNA H19 in HIE. We selected three HIE newborns and three healthy newborns for neonatal behavioral neurological assessment and screened the differentially expressed lncRNAs by microarray analysis and detected H19 expression in serum. After that, neonatal HIE rats were established and injected with H19 overexpression lentivirus vector or autophagy activator Rapa. The structure and apoptotic levels of brain tissue were observed, and righting reflex and geotaxis reflex were utilized to evaluate the short-term neurological function of HIE rats. The Morris water maze was performed to measure the long-term neurological functions of HIE rats. The binding relationships among H19/miR-19b/protein kinase B3 (Akt3) were verified. Levels of Akt3- and autophagy-related proteins were measured. H19 was upregulated in HIE newborns and rat models. The areas of cerebral infarction and apoptosis in neonatal HIE rats were increased, and the nerve functions were compromised. The overexpression of H19 alleviated nerve damage of neonatal HIE rats, and reduced autophagy of brain tissue. H19 upregulated Akt3 as a miR-29b sponge. The protective effects of overexpression of H19 on brain tissue and nerve functions of neonatal HIE rats were partially reversed by autophagy activator. H19 improved the brain tissue and alleviated nerve damage of neonatal HIE rats by upregulating the Akt3/mTOR pathway as a miR-29b sponge. · H19 overexpression reduces the nerve damage in neonatal HIE rats.. · H19 reduces autophagy in neonatal HIE rats by the miR-29b/Akt3/mTOR axis.. · Autophagy activator reverses the protection of H19 in neonatal HIE..

Role of Sirtuin-1 in Neonatal Hypoxic-Ischemic Encephalopathy and Its Underlying Mechanism.

BackgroundNeonatal hypoxic-ischemic encephalopathy (HIE) is a dreaded disease and one of the leading causes of severe neurological dysfunction in neonates. The present study explored the functions of Sirtuin-1 (SIRT1) in neonatal HIE.Material/MethodsA HIE neonatal rat model was generated to determine SIRT1 levels in brain tissues. Cell apoptosis and cell viability were analyzed by flow cytometry and MTT assay. qRT-PCR and Western blot analysis were used to assess gene mRNA and protein levels. Subsequently, the effect of SIRT1 on HIE was investigated in vitro by constructing an oxygen-glucose deprivation (OGD) cell model.ResultsThe effective construction of the HIE rat model was confirmed by the enhanced brain cell apoptosis and the increased expression of HIE-related molecular markers, including S100 calcium-binding protein B (S100B) and neuron-specific enolase (NSE). SIRT1 expression was downregulated in HIE rat brain tissues. These findings indicated that SIRT1 was downregulated in neuronal cells subjected to OGD. In addition, enhanced cell viability and reduced cell apoptosis were observed, suggesting that SIRT1 overexpression relieved OGD-induced neuronal cell injury. Transfection with SIRT1-siRNA further increased OGD-induced neuronal cell injury, evidenced by decreased cell viability and enhanced cell apoptosis. Finally, SIRT1 overexpression significantly downregulated p-p65 protein expression.ConclusionsOur findings revealed that SIRT1 may be a novel and promising therapy target for HIE treatment.

TAK‑242 exerts a neuroprotective effect via suppression of the TLR4/MyD88/TRIF/NF‑κB signaling pathway in a neonatal hypoxic‑ischemic encephalopathy rat model.

Neonatal hypoxic-ischemic encephalopathy (HIE) is one of the main causes of death and nervous system damage in neonates. The aim of the present study was to investigate the effect of the Toll-like receptor 4 (TLR4) antagonist TAK-242 on HIE. The Rice-Vannucci method was used for ligation of the left common carotid artery, followed by hypoxic treatment for 2.5 h to establish a neonatal HIE rat model. Rats were intraperitoneally injected with 7.5 ml/kg TAK-242 after hypoxia-ischemia. It was demonstrated that TAK-242 significantly reduced the infarct volume and cerebral edema content of neonatal rats after HIE, alleviating neuronal damage and neurobehavioral function deficits. Furthermore, TAK-242 decreased the protein expression levels of TLR4, MyD88, TIR-domain-containing adapter-inducing interferon-β (TRIF), NF-κB, tumor necrosis factor α (TNF-α) and interleukin-1β in the hippocampus. The present results suggested that TAK-242 may exert a neuroprotective effect after HIE by inhibiting the TLR4/MyD88/TRIF/NF-κB signaling pathway, and reducing the release of downstream inflammatory cytokines.