Neuroglobin and neuroprotection:the role of natural and synthetic compounds in neuroglobin pharmacological induction

Neuroglobin(Ngb)is a 17 kDa monomeric hexa-coordinated heme protein belonging to the globin family.Ngb is mainly expressed in neurons of the central and peripheral nervous system,although moderate levels of Ngb have been detected in non-nervous tissues.In the past decade,Ngb has been studied for its neuroprotective role in a large number of neurological disorders such as Alzheimer’s disease,Huntington’s disease,brain ischemia and hypoxia.This review discusses and summarizes the natural compounds and the small synthetic molecules capable of modulating Ngb expression that exhibits a protective role against various neurodegenerative diseases.

大鼠急性青光眼模型中neuroglobin在视网膜的表达上调作用

目的研究大鼠急性青光眼模型中neuroglobin(NGB)的表达变化。方法制备大鼠急性青光眼模型,采用RT-PCR技术动态观察不同缺血时间点NGB mRNA水平变化,并对数据进行分析。结果视网膜缺血1 min,neuroglobinmRNA表达迅速上升,5 min时neuroglobin mRNA表达保持在高水平,到10 min时达高峰,缺血20 min表达已下降,但仍高于正常水平;此后缺血30 min、60 min时neuroglobin mRNA均保持在较低水平,且低于正常水平。结论Neuroglobin表达可能在视网膜缺血缺氧的病理变化过程中起重要作用;表达量的变化与缺血缺氧的时间呈线性相关,可能在视网膜缺氧保护过程中发挥重要的分子机制。

Neuroglobin 基因体内转染对水杨酸钠给药后小鼠下丘核神经元听反应的影响(英文)

实验以48只成年健康昆明小鼠为实验对象,研究GeneJamer转染试剂介导的neuroglobin(NGB)基因体内转染对水杨酸钠给药后小鼠下丘核区听反应的影响。实验分4组,每组12只。A1组:对照组1(阴性对照,将GeneJamer转染试剂6μl和pEGFP-C12μg混合后注入下丘核脑区);A2组:对照组2[阳性对照,将GeneJamer转染试剂(6μl)和pEGFP-NGB(质粒载体pEGFP-C1与NGB基因全编码序列构建的重组子2μg)混合后注入下丘核脑区];B组:水杨酸钠给药组(450mg/kg·d-1)+pEGFP-C1;C组:水杨酸钠(450mg/kg.d-1)+pEGFP-NGB组。以直接注射法将GeneJamer转染试剂和重组质粒pEGFP-NGB混合后注入小鼠下丘核区。采用RT-PCR和Westernblot技术检测小鼠下丘核区NGBmRNA和蛋白的表达;采用细胞外记录技术,研究小鼠下丘核区神经元在水杨酸钠给药后转染重组质粒pEGFP-NGB对强度-发放率函数(刺激声强与实验鼠下丘核区神经元在接受声刺激所产生的电发放的关系曲线)、强度-潜伏期函数(刺激声强与实验鼠下丘核区神经元在接受声刺激至产生电发放潜伏期之间的关系曲线)和频率调谐曲线(实验鼠下丘核区神经元在各个频率纯音刺激下起反应的阈值绘制的曲线)的影响。实验观察到:(1)经GeneJamer转染试剂介导NGB基因可有效地转染小鼠下丘核区脑组织并得到表达。(2)水杨酸钠给药后神经元的强度-发放率函数曲线升高。对照组A1、A2各项指标进行比较均无统计学意义。对照组A1、A2和水杨酸钠+pEGFP-NGB组神经元的强度-发放率函数以非单调型(随刺激强度增加时,发放率表现为先降后升呈“V”形或“U”形)为主,分别占74.6%、72.2%和59.3%,水杨酸钠给药组以不规则型强度-发放率函数为主,占47%,与对照组A1、A2和水杨酸钠+pEGFP-NGB组比较,有显著性差异(P<0.01、P<0.01、P<0.05)。(3)水杨酸钠给药后神经元的强度-潜伏期函数曲线降低。对照组A1、A2各项指标进行比较均无统计学意义。水杨酸钠给药组以非单调型强度-潜伏期率函数为主,与对照组A1、A2和水杨酸钠+pEGFP-NGB组比较,有显著性差异(P<0.01、P<0.05)。(4)A1和A2对照组听反应神经元的调谐曲线,Q-10dB值均大于5.00,其调谐曲线为狭窄型。记录水杨酸钠给药组72个听神经元的调谐曲线,有53个神经元的Q-10dB值小于5.00,Q-10dB值最小为2.12,其调谐曲线为宽阔型;其余19个神经元的Q-10dB值大于5.00,属于狭窄型调谐曲线。水杨酸钠+pEGFP-NGB组67个听神经元的调谐曲线,有12个神经元的Q-10dB值小于5.00,Q-10dB值最小为2.87,其调谐曲线为宽阔型,其它的神经元的值大于5.00。它们的调谐曲线均属狭窄型。以上结果提示外源性NGB基因在水杨酸钠给药后小鼠下丘核区局部高表达,提示GeneJamer转染试剂介导NGB体内转基因治疗水杨酸钠引起的下丘核区的损伤的方法是可行的。实验小鼠转染NGB基因后可逆转因水杨酸钠给药引起的强度-发放率函数曲线升高以及强度-潜伏期函数曲线降低,并可逆转水杨酸钠引起的部分听神经元对声刺激强度的编码类型。

Neuroglobin expression in rats after traumatic brain injury

In this study, we used a rat model of severe closed traumatic brain injury to explore the relationship between neuroglobin, brain injury and neuronal apoptosis. Real-time PCR showed that neuroglobin mRNA expression rapidly increased in the rat cerebral cortex, and peaked at 30 minutes and 48 hours following traumatic brain injury. Immunohistochemical staining demonstrated that neuroglobin expression increased and remained high 2 hours to 5 days following injury. The rate of increase in the apoptosis-related Bax/Bcl-2 ratio greatly decreased between 30 minutes and 1 hour as well as between 48 and 72 hours post injury. Expression of neuroglobin and the anti-apoptotic factor Bcl-2 greatly increased, while that of the proapoptotic factor decreased, in the cerebral cortex post severe closed traumatic brain injury. It suggests that neuroglobin might protect neurons from apoptosis after traumatic injury by regulating Bax/Bcl-2 pathway.

Cerebroprotection with recombinant neuroglobin plasmid in a rat model of focal cerebral ischemia

BACKGROUND： Adenovirus has been used to develop neuroglobin （Ngb） vectors. Although transfection efficiency is high, induced gene mutation, cytotoxicity, inflammation, and low exogenous gene content have limited its application. OBJECTIVE： To observe the effects of recombinant Ngb plasmid in a rat model of focal cerebral ischemia. DESIGN, TIME AND SETTING： Genetically engineered, randomized, controlled, animal experiment was performed at the Laboratory of Chongqing Medical University from May 2006 and January 2007. MATERIALS： 2, 3, 5-triphenyltetrazolium chloride was purchased from Shanghai Sangon Biological Engineering Technology and Services. Rabbit anti-rat Bcl-2 polyclonal antibody, rabbit anti-rat β-actin monoclonal antibody, and FITC-labeled goat anti-rabbit IgG were purchased from Sigma, USA. TUNEL apoptosis kit was purchased from Roche, Germany. METHODS： A total of 54 male, adult, Wistar rats were randomly assigned to 3 groups （n=18）： normal saline, plasmid control, and recombinant Ngb （pCDNA3.1 （＋）/Ngb）. Normal saline, plasmid pCDNA3.1 （＋）, and recombinant plasmid pCDNA3.1 （＋）/Ngb were separately injected into two sites in the rat cerebral cortex, and models of focal ischemia were established by occlusion of the right middle cerebral artery after 24 hours. MAIN OUTCOME MEASURES： Local ischemic damage was detected by 2, 3, 5- triphenyltetrazolium chloride staining, apoptosis in the penumbra was confirmed using the TUNEL method, and Bcl-2 protein expression in the penumbra was determined by indirect immunofluorescent staining and Western blot analysis. RESULTS： Compared with the normal saline and plasmid control groups, cerebral infarction size and the number of apoptotic cells in the pCDNA3.1 （＋）/Ngb group were significantly reduced （P 〈 0.01）. The percentage of Bcl-2-positive cells in the penumbra of the pCDNA3.1 （＋）/Ngb group was significantly increased （P 〈 0.01）. The relative expression level of Bcl-2 protein was increased by 40%-50%. CONCLUSION： Recombinant plasmid pCDNA3.1/Ngb provides neuroprotection by upregulating Bcl-2 expression and inhibiting cell apoptosis in the penumbra.

Overexpression of the neuroglobin gene delivered by ultrasound-targeted microbubble destruction protects SH-SY5Y cells against cobalt chloride induced hypoxia

In this study, we examined the effects of neuroglobin gene （Ngb） transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction （UTMD）, on cobalt chloride-induced hypoxia. With an ultrasound intensity of 0.8 W/cm2, a 60-second exposure duration, 50% duty cycle, and 20% microbubble concentration, pAcGFP1-C1-Ngb-transfected cells exhibited the highest cell viability and transfection efficiency. The efficiency of plasmid delivery was significantly higher with UTMD than transfection with plasmid alone, transfection with plasmid using microbubbles, or transfection of plasmid by ultrasound. In addition, during cobalt chloride-induced hypoxia, caspase-3 activity in pAcGFP1-C1-Ngb-transfected cells was significantly lower than in untransfected cells. Ngb protein and mRNA expression were significantly higher in cells transfected by UTMD than in cells transfected with the other methods. These results demonstrate that UTMD can very efficiently mediate exogenous gene delivery, and that Ngb overexpression protects cells against cobalt chloride-induced hypoxia.

Significance of neuroglobin in serum of acute atherosclerotic cerebral infarction patients

This study sought to examine neuroglobin （NGB） in the serum of acute cerebral infarction patients with double-antibody sandwich enzyme-linked immunosorbent assay to identify all risk factors, calculate infarct size, assess neurological impairment, and analyze the relation between NGB and each of these factors. The double-antibody sandwich assay indicated that levels of NGB in serum were unaltered within 6 hours following acute cerebral infarction compared with normal levels. NGB levels then underwent a distinct change, peaking at 24 hours then returning to normal levels in 72 hours. The results suggest that the level of NGB might be related to infarct size and low-density lipoprotein at 24 hours after acute cerebral infarction. There were no significant differences in neurological impairment scores and infarct size at different periods following infarction. The findings indicated that the level of NGB in serum of acute cerebral infarction patients was correlated with infarct time.

Determination of vinyl orientation of mouse neuroglobin by 2D nuclear Overhauser spectroscopy

^1H NMR has been used to determine the 2-, 4-vinyl orientation of heme active site from oxidized mouse neuroglobin （mNgb）. The NOEs between 3-methyl and Hα, Hβ of 2-vinyl, together with the NOEs between 5-methyl and Hα, Hβ of 4-vinyl, allowed the unambiguous determination of trans and cis orientations for the 2- and 4-vinyl groups in the mNgb, respectively.

Contribution at the Study of Neuroprotective Properties of Neuroglobin during Severe Chronic Glaucoma

Introduction: The mechanisms of overexpression of neuroglobin in patients with severe glaucoma (CG+) remain hypothetical. Objective: To study the anti-apoptotic, anti-hypoxic and anti-oxidant properties of neuroglobin in CG+. Population and Methods: The visual field, as well as plasma dosage of neuroglobin (CmNgb, ng/ml), hypoxia inductible factor-1alpha (CmHIF-1α, pg/ml), glutathione peroxidase (CmGpx, pg/ml), and cytochrome C oxidase (CmCyt C, pg/ml) were carried out in 45 CG+ and 45 controls (CG-). The chi-2 test compared the proportions, and Spearman’s test studied the correlations between quantitative variables (p Results: CmNgb was 4.1 in CG+, versus 2.3 in CG- (p = 1.52 × 10-5). CmGpx was 1144.7 in CG+, versus 752.8 in GC- (p = 0.0199). CmHIF-1α was 4.1 in CG+, versus 3.5 in CG- (p = 0.4530). CmCyt C was 2303.26 in CG+, versus 1750.44 in CG- (p = 0.0450). In CG+, there was a correlation between CmNgb and CmGpx (r = 0.417;p = 0.004), CmNgb and CmHIF-1α (r = 0.644;p = 1.8 × 10-6), and between CmHIF-1α and CmGpx (r = 0.447;p = 0.002), CmHIF-1α and CmCyt C (r = 0.371;p = 0.012). None correlation was found between CmNgb and CmCyt C (r = 0.126;p = 0.370), as well as CmGpx and CmCyt C (r = 0.102;p = 0.505). Conclusion: The variations of apoptosis, hypoxic, and oxidative stress biomarkers were found between CG+ and CG-, as well as their correlations, suggesting that neuroglobin overexpression is related to its anti-apoptotic, anti-oxidative, and anti-hypoxic properties.

Diagnostic and Prognostic Interests of Plasmatic Neuroglobin during Stroke in Adult at the Acute Phase

Introduction: Neuroglobin (Ngb) owes its name to its preferred location in the nervous system. Its plasma concentration increases during cerebral ischemia. However, the interest of its dosage in the diagnosis and the prognosis of the strokes in the adult is not defined. Objectives: To determine if plasmatic Ngb can be used as a diagnostic biomarker and prognostic for stroke in adults at the acute phase. Population and Methods: This was a prospective study in 69 people, including 39 suspected stroke (Cerebral ischemia or CI, Intracerebral hemorrhage or ICH) and 30 healthy volunteers (controls). The plasma concentration of Ngb (CmNgb in ng/ml) of the patients was determined at admission day (d1), at the third day (d3) and seventh day (d7). CmNgbtaken at d1 was compared between patients and controls. Its evolution over time, as well as its relation with the clinical parameters, including the Glasgow coma scale and the short-term mortality in stroke subjects was analyzed by the Mann and Whitney tests and the Wilcoxon test (p Results: At d1, the CmNgb of all types of stroke was 3.140 ± 2.700 ng/ml, and did not differ significantly from controls (0.303 ± 0.114 ng/ml, p = 0.070). On the other hand, it was higher in CI victims (5.800 ± 0.720 ng/ml) than in ICH (1.750 ± 0,090 ng/ml) (p = 0.030). It then decreased on d3 in CI victims (2.600 ± 0.112 ng/ml) and ICH (0.420 ± 0.211 ng/ml), returning to normal on d7 (0.420 ± 0.200 ng/ml for CI’s, p = 0.001, and 0.360 ± 0.300 ng/ml for ICH, p = 0.002). There was a relationship between CmNgb, delay of occurrence of the first symptoms of the stroke (3.140 ± 2.700 ng/ml before the 6th hour, and 0.643 ± 0.244 ng/ml after the 6th hour (p = 0.003) and the volume of the hematoma (p = 0.0027). None relationship existed between CmNgb, Glasgow coma scale (p = 0.427) and short-term mortality (CmNgb = 3.95 ng/ml in survivors versus 2.65 ng/ml in deceased p = 0.060). Conclusion: This study shows that the plasma concentration of Neuroglobin is high during stroke in humans in the acute phase. This elevation follows triphasic?kinetics and appears to be more important during infarction than hemorrhage. These results suggest that CmNgb can be used as a diagnostic marker for stroke in adult at the acute phase, by differentiating ischemia from hemorrhage. However, this work needs to be confirmed on a larger sample of patients.

Expression of neuroglobin in ocular hypertension induced acute hypoxic-ischemic retinal injury in rats

AIM: To investigate the Expression of neuroglobin (Ngb) in the retina of rats with ocular hypertension induced acute retinal hypoxic-ischemic injury. METHODS: Seventy Wistar rats were divided into 7 groups randomly. The Experimental model was induced by elevation of intraocular pressure via anterior chamber canula insertion in the left eyes and the fellow eyes were preserved as normal controls. The retinal tissues were taken at 1, 5, 10, 15, 20, 30 and 60 minutes after hypoxic-ischemia injury. Protein was extracted, and then analyzed by Western-blot method. SPSS was used for statistical analysis. RESULTS: The time-depended expressions of Ngb were observed. The level of Ngb increased rapidly at 1 minute after ischemia and reached to the peak at 5 minutes, which had significant difference from that of control group (P<0.05). It kept in high level during 5-15 minutes (P <0.05), then decreased after 20 minutes till 60 minutes. There were no significant differences between experimental and control group in the latter period (P> 0.05). CONCLUSION: The expression of Ngb in retinal tissue increased rapidly after hypoxic-ischemic injury in rats, suggesting that Ngb may play an important role in the process of acute retinal hypoxic-ischemic injury.

Neurological adaptations to hypoxia in Tibetan antelope (Pantholops hodgsonii) with a view of molecular biology of respiratory globin-neuroglobin

Neuroglobin(Ngb) is a respiratory protein that is preferentially expressed in brain of mouse and man.In this article,Tibetan antelope,living at altitude of 3 000～5 000 m for millions of years,was selected as the model of hypoxia-tolerant adaptation species.Using reverse transcription polymerase chain reaction(RT-PCR) and Western blot techniques,expression of Ngb gene was amplified and analyzed in antelope brain tissue.Our results showed that Ngb homology protein in Tibetan antelope was identified with more sequence similarity with cattle(96%),sheep(95%),and human(95%).We detected that there were some mutations occurred in the Open Reading Frame of Ngb in Tibetan antelope compared with sheep.Phylogenetic analysis of Ngb chain showed that it was closer to cattle than the others.This study suggests possible roles of central nervous system enriched Ngb in adaptation of Tibetan antelope to extremely high altitude.

Neuroglobin Facilitates Neuronal Oxygenation through Tropic Migration under Hypoxia or Anemia in Rat:How Does the Brain Breathe?

The discovery of neuroglobin(Ngb),a brain-or neuron-specific member of the hemoglobin family,has revolutionized our understanding of brain oxygen metabolism.Currently,how Ngb plays such a role remains far from clear.Here,we report a novel mechanism by which Ngb might facilitate neuronal oxygenation upon hypoxia or anemia.We found that Ngb was present in,co-localized to,and co-migrated with mitochondria in the cell body and neurites of neurons.Hypoxia induced a sudden and prominent migration of Ngb towards the cytoplasmic membrane(CM)or cell surface in living neurons,and this was accompanied by the mitochondria.In vivo,hypotonic and anemic hypoxia induced a reversible Ngb migration toward the CM in cerebral cortical neurons in rat brains but did not alter the expression level of Ngb or its cytoplasm/mitochondria ratio.Knock-down of Ngb by RNA interference significantly diminished respiratory succinate dehydrogenase(SDH)and ATPase activity in neuronal N2a cells.Over-expression of Ngb enhanced SDH activity in N2a cells upon hypoxia.Mutation of Ngb at its oxygen-binding site(His64)significantly increased SDH activity and reduced ATPase activity in N2a cells.Taken together,Ngb was physically and functionally linked to mitochondria.In response to an insufficient oxygen supply,Ngb migrated towards the source of oxygen to facilitate neuronal oxygenation.This novel mechanism of neuronal respiration provides new insights into the understanding and treatment of neurological diseases such as stroke and Alzheimer’s disease and diseases that cause hypoxia in the brain such as anemia.

血清NSE、NGB水平与新生儿缺氧缺血性脑病严重程度的相关性及对预后的预测价值研究

目的:研究血清神经元特异性烯醇化酶(NSE)、脑红蛋白(NGB)水平与新生儿缺氧缺血性脑病(HIE)严重程度的相关性及对预后的预测价值,为临床提供参考。方法:选取2015年6月—2021年6月开封市妇产医院收治的152例HIE患儿作为研究对象,将其设为疾病组。另选取同期于开封市妇产医院出生的健康新生儿50例,将其设为正常组。比较两组新生儿血清NSE、NGB水平。根据病情严重程度分疾病组为轻度组(48例)、中度组(59例)、重度组(45例)。比较三组患儿血清NSE、NGB水平。采用Spearman相关性分析法分析血清NSE、NGB与HIE严重程度的相关性。随访6个月,根据患儿预后情况将其分为良好组(115例)、不良组(33例),采用logistic回归分析HIE预后不良的危险因素。绘制新生儿工作特征曲线(ROC),分析血清NSE、NGB对HIE预后不良的预测价值。结果:疾病组血清NSE、NGB水平高于正常组,差异有统计学意义(t=31.041、43.497,P<0.05)。中、重度组血清NSE、NGB水平高于轻度组,重度组血清NSE、NGB水平高于中度组,差异有统计学意义(F=191.507、143.945,P<0.05)。Spearman相关性分析结果显示,血清NSE、NGB水平与HIE严重程度呈正相关(r=0.853、0.830,P<0.05)。logistic回归分析结果显示,5 min Apgar评分≤7分、HIE严重程度为重度、发病至治疗时间≥48 h是HIE预后不良的危险因素,差异有统计学意义(OR=3.149、3.677、1.865、2.396、5.726,P<0.05)。ROC显示,血清NSE、NGB预测HIE预后不良的最佳截断点分别为33.05 ng/mL、203.09 pg/mL,单独及联合预测的ROC下面积(AUC)分别为0.784、0.821、0.890,两者联合检测的预测价值高于单独检测。结论:血清NSE、NGB水平与新生儿HIE严重程度呈正相关,且两者联合检测对该病预后具有较高的预测价值。

Circular dichroism spectral studies on the recombinant human neuroglobin

Neuroglobin (NGB) is a newly discov- ered member of the hemoglobin superfamily that is primarily expressed in the brain of humans and other vertebrates. The effects of protein concentration, solvent, pH and temperature on the secondary structure of NGB were investigated by employing far UV circular dichroism (CD) spectroscopy. The results show that NGB exists mainly in α-helix form when its concentration is less than 10 μmol/L. However, its α-helix content decreases with the increase of con- centration in the range of 10―40 μmol/L and remains unchanged when the concentration is higher than 40 μmol/L, which suggest that NGBs form intermolecular disulfide bond and aggregate in higher concentration. The α-helix content of NGB in methanol and ethanol is a little higher than that in water, indicating a higher stability of NGB in these solvents. NGB loses its α-helical secondary structure in either acidic or alka- line solution to some extent. Although increased temperature destabilizes the α-helices of NGB, over 16% of α-helices can be kept at 110°C. Therefore, NGB is a protein with hyperthermal stability.

Expression,purification and spectra characterization of neuroglobin

The expression, purification and spectra char-acterization of recombinant human neuroglobin (NGB) are reported. The pET3a plasmid with the gene of NGB was transformed to E. coli BL21 (DE3) plys cells and expressed in TB culture medium. The results indicated that the expression amount of NGB is about 10 percent of the total protein in cells. The NGB protein was purified by ammonium sulfate precipitation, DEAE-Sepharose anion exchange column, Hiload 16/60 superdex 75 size exclusion chromatography and a Hiprep 16/10 Q FF anion exchange column, and a red solu-ble protein was obtained which showed a single band in elec-trophoresis. Electrospray ionization mass spectrometry (ESI-MS) showed that its molecular weight is 16930.0 Da. UV-spectra indicated that the reduced NGB has a strong absorption peak at 425 nm, and two weak peaks at 531 and 559 nm, which can be assigned to γ, β and α bands of por-phyrin, respectively, and the oxidized NGB has a strong ab-sorption peak at 413 nm which corresponds to the transition of π electrons in the porphyrin ring. The fluorescence maxi-mal excitation wavelength is at 281 nm and its maximal emission wavelength is at 338 nm. CD spectra indicated that its secondary structure is a typical α helix, and has a positive peak at 410 nm induced by heme. The NGB protein is stable when the pH is higher than 4.

脑红蛋白在赛加羚羊脑组织中的表达与定位

目的赛加羚羊(Saiga antelope)是小种群栖息在荒漠和半荒漠地带的国家及世界濒危保护动物,其野生种群极为罕见。为了探讨赛加羚羊的低氧耐受性与脑红蛋白(NGB)的相关性,以1只因难产而死的雌性赛加羚羊为对象,各组织样品重复取样3次,对赛加羚羊脑组织在适应低氧过程中脑红蛋白的分布情况与表达规律进行了研究。方法利用免疫组织化学和Real-time PCR技术,检测NGB在赛加羚羊脑组织顶叶、额叶、颞叶、枕叶、下丘脑、海马、梨状叶、扣带回、纹状体和丘脑中分布特征和表达量。结果免疫组织化学染色结果表明,NGB在赛加羚羊脑组织的各部位均有阳性表达,在大脑皮质顶叶、额叶、颞叶和枕叶中发生阳性反应的细胞多为颗粒细胞和马丁诺蒂细胞;海马中的颗粒细胞层、锥体细胞层和分子细胞层均可见NGB的阳性表达,其中锥体细胞层阳性反应着色最强;梨状叶和下丘脑中的NGB阳性表达主要发生在多型细胞中;NGB在扣带回的颗粒细胞和胶质细胞中均有阳性表达,主要表达于颗粒细胞中;NGB在纹状体中的阳性表达主要定位于颗粒细胞;NGB在丘脑中的阳性表达可见于多型细胞和神经胶质细胞,且多型细胞的阳性物质着色明显。Real-time PCR结果表明,NGB在赛加羚羊脑组织不同区域中均有表达,在大脑皮质的额叶中表达量最高,顶叶表达量次之,且表达量均显著高于脑组织其余区域(P<0.05);其中,海马、下丘和丘脑中的表达量显著高于其余区域(P<0.05);梨状叶表达量显著高于颞叶、枕叶、扣带回和纹状体(P<0.05);颞叶和枕叶的表达量显著高于扣带回和纹状体(P<0.05);在扣带回和纹状体中的表达量最低(P>0.05)。结论赛加羚羊脑组织不同区域NGB的表达在长期适应低氧环境过程中存在一定的选择性差异,额叶和顶叶对低氧具有相对最高的耐受度,海马等次之,纹状体对低氧耐受度相对最弱,这可能与脑组织不同区域的特定功能有关。

脑红蛋白在神经细胞铁死亡中的作用研究

目的:探讨脑红蛋白在神经细胞铁死亡中的作用。方法:通过构建小鼠海马神经元细胞HT22的脑红蛋白(neuro-globin,NGB)敲低模型,分别检测Normal组、Erastin组、NGBsiRNA组和NGBsiRNA+Erastin组,细胞增殖活性、铁离子含量、丙二酵含量、超氧化物含量、活性氧含量等铁死亡相关指标,及核因子E2相关因子2(nuclear factor E2-related factor 2,Nrf2)表达的变化情况。结果:Norma组相比,Erastin组、NGBsiRNA组和NGBsiRNA+Erastin组细胞增殖活性和Nrf2表达量均显著降低,铁离子含量、丙二酵含量、超氧化物含量、活性氧含量等铁死亡相关指标均显著升高,NGBsiRNA+Erastin组与Erastin组、NGBsiRNA组相比差异有统计学意义(p<0.05)。结论:敲低NGB可以增强铁死亡诱导剂Eras-tin的作用,NGB可能通过Nrf2调控细胞铁死亡过程,该研究为中医药临床治疗神经系统疾病提供参考。

血清HO-1、脑红蛋白和NPY对新生儿黄疸患儿发生脑损伤的诊断价值

目的观察血清血红素氧化酶(HO)-1、脑红蛋白和神经肽Y(NPY)检测对新生儿黄疸患儿发生脑损伤的诊断价值。方法选择2019年1月至2021年12月在该院诊治的新生儿黄疸患儿216例作为黄疸组,同时根据黄疸的严重程度将其分为轻度组(99例)、中度组(85例)和重度组(32例),根据脑部诊断结果分为无脑损伤组(192例)和脑损伤组(24例);另选取同期在该院出生的健康新生儿55例作为对照组。观察黄疸组患儿治疗前后血清HO-1、脑红蛋白和NPY的水平变化并与对照组进行比较,探讨血清HO-1、脑红蛋白和NPY水平与新生儿黄疸严重程度和脑损伤的关系,以及其对新生儿黄疸患儿脑损伤的诊断效能。结果治疗前黄疸组血清HO-1、脑红蛋白和NPY水平明显高于对照组(P<0.05),治疗后黄疸组血清HO-1、脑红蛋白和NPY水平较治疗前明显降低(P<0.05)。血清HO-1、脑红蛋白和NPY水平明随着新生儿黄疸严重程度的升高而升高(P<0.05)。脑损伤组血清HO-1、脑红蛋白和NPY水平明显高于无脑损伤组(P<0.05)。血清HO-1、脑红蛋白和NPY对新生儿黄疸患儿脑损伤具有较高的诊断效能,三者联合检测灵敏度为95.8%,特异度为94.8%,曲线下面积(AUC)为0.966,明显高于HO-1、脑红蛋白、NPY单独检测(P<0.05),而3个指标之间的AUC比较,差异无统计学意义(P>0.05)。新生儿黄疸患儿血清HO-1水平与脑红蛋白、NPY呈正相关(r=0.766、0.875,P<0.05),血清脑红蛋白水平和NPY呈正相关(r=0.832,P<0.05)。结论血清HO-1、脑红蛋白和NPY水平是判断新生儿黄疸严重程度的指标,三者联合检测有助于提高对新生儿黄疸患儿脑损伤的诊断效能。