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1.
Braz J Biol ; 83: e245330, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495146

RESUMO

BACKGROUND: The brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. AIM: The study examined the expression of Neuroglobin (Ngb) and Hypoxia-inducible factor-1α (Hif-1α) in adult and young yak brain tissues, and provided researchers with meaningful insight into the anatomy, physiology, and biochemistry of this mammal. METHOD: The study employed immunohistochemistry (IHC), quantitative real-time PCR (qRT-PCR), and Western blot (WB) to obtain the results. RESULTS: Ngb and Hif-1α were significantly (P<0.05) expressed in the cerebellar cortex, piriform lobe, medulla, and corpus callosum of the adult yak while in the young yak brain tissues, the protein expressions were significantly found in the white matter of the cerebellum, pineal gland, corpus callosum, and cerebellar cortex. The Ngb and Hif-1α expression showed similarities and differences. This may have resulted from similar animal species, source of nutrition, age factors, brain size, emotional activities, and communication. The findings documented that Ngb and Hif-1α are commonly expressed in various adult and young yak brain tissues. Multiple roles in the brain tissues of the adult and young yaks are involved in the expression and distribution and are proposed to play a significant role in the adaptation of the yak to the high altitude environment. CONCLUSION: This study provides meaningful data to understand the adaptive mechanism to hypoxia and recommended researchers to expand on the adaptive mechanism and brain tissues that are not recorded.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Hipóxia , Animais , Encéfalo , Bovinos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neuroglobina , RNA Mensageiro
2.
Braz J Biol ; 83: e248911, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495167

RESUMO

The telencephalon refers to the most highly developed and anterior part of the forebrain, consisting mainly of the cerebral hemispheres. The study determined Neuroglobin (Ngb) and Hypoxia-inducible factor (HIF-1α) expression in the telencephalon of yak and cattle, and compare the expression and distribution pattern of Ngb and HIF-1α in the two animals. Immunohistochemistry (IHC), quantitative real-time Polymerase Chain Reaction (qRT-PCR), and Western blot (WB) were employed to investigate Ngb and Hif-1α expression in the telencephalon of yak and cattle. mRNA and protein expressions of Ngb and HIF-1α showed positive in different tissues of the yak and cattle telencephalon. Ngb expression in tissues of the yak recorded higher as compare to cattle while HIF-1α expression was found higher in cattle than yak. The HIF-1α expression in some tissues of yak telencephalon was consistent with the cattle. The results documented that HIF-1α may have a direct or indirect synergistic effect on Ngb expression in the yak telencephalon to improve hypoxia adaptation. It is suggested that yak may need more Ngb expression for adaptation, but the expression of HIF-1α seems to be down-regulated during long-term adaptation, and the specific causes of this phenomenon needs to be further verified.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Telencéfalo , Adaptação Fisiológica , Animais , Bovinos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Neuroglobina , RNA Mensageiro/genética
3.
Cells ; 10(8)2021 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-34440676

RESUMO

Estradiol exerts neuroprotective actions that are mediated by the regulation of a variety of signaling pathways and homeostatic molecules. Among these is neuroglobin, which is upregulated by estradiol and translocated to the mitochondria to sustain neuronal and glial cell adaptation to injury. In this paper, we will discuss the role of neuroglobin in the neuroprotective mechanisms elicited by estradiol acting on neurons, astrocytes and microglia. We will also consider the role of neuroglobin in the neuroprotective actions of clinically relevant synthetic steroids, such as tibolone. Finally, the possible contribution of the estrogenic regulation of neuroglobin to the generation of sex differences in brain pathology and the potential application of neuroglobin as therapy against neurological diseases will be examined.


Assuntos
Encefalopatias/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Estradiol/uso terapêutico , Estrogênios/uso terapêutico , Neuroglobina/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Encefalopatias/metabolismo , Encefalopatias/patologia , Estradiol/metabolismo , Feminino , Humanos , Masculino , Neurônios/metabolismo , Neurônios/patologia , Fatores Sexuais , Transdução de Sinais
4.
Cells ; 10(8)2021 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-34440755

RESUMO

The expression of the α-subtype of Estrogen Receptor (ERα) characterizes most breast cancers (more than 75%), for which endocrine therapy is the mainstay for their treatment. However, a high percentage of ERα+ breast cancers are de novo or acquired resistance to endocrine therapy, and the definition of new targets for improving therapeutic interventions and the prediction of treatment response is demanding. Our previous data identified the ERα/AKT/neuroglobin (NGB) pathway as a common pro-survival process activated in different ERα breast cancer cell lines. However, no in vivo association between the globin and the malignity of breast cancer has yet been done. Here, we evaluated the levels and localization of NGB in ERα+ breast ductal carcinoma tissue of different grades derived from pre-and post-menopausal patients. The results indicate a strong association between NGB accumulation, ERα, AKT activation, and the G3 grade, while no association with the menopausal state has been evidenced. Analyses of the data set (e.g., GOBO) strengthen the idea that NGB accumulation could be linked to tumor cell aggressiveness (high grade) and resistance to treatment. These data support the view that NGB accumulation, mainly related to ER expression and tumor grade, represents a compensatory process, which allows cancer cells to survive in an unfavorable environment.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/química , Carcinoma Ductal de Mama/química , Receptor alfa de Estrogênio/análise , Neuroglobina/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/mortalidade , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/terapia , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Gradação de Tumores , Intervalo Livre de Progressão , Proteínas Proto-Oncogênicas c-akt/análise , Transdução de Sinais , Microambiente Tumoral
5.
Medicine (Baltimore) ; 100(15): e25446, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33847649

RESUMO

ABSTRACT: To investigate whether plasma concentrations of S100ß protein, neuron-specific enolase (NSE), and neuroglobin (NGB) correlate with early postoperative cognitive dysfunction (POCD) in patients undergoing total arch replacement.This prospective study analyzed 40 patients who underwent total arch replacement combined with stented elephant trunk implantation at our hospital between March 2017 and January 2019. Cognitive function was assessed using the Mini-mental State Examination (MMSE) preoperatively, on the day after extubation and on day 7 after surgery. Plasma levels of S100ß, NSE, and NGB POCD were assayed preoperatively and at 1, 6, and 24 hours after cardiopulmonary bypass. POCD was defined as a decrease of at least 1 unit in the MMSE score from before surgery until day 7, and patients were stratified into those who experienced POCD or not. The 2 groups were compared in clinicodemographic characteristics and plasma levels of the 3 proteins.Plasma levels of all 3 biomarkers increased significantly during and after cardiopulmonary bypass. Levels of S100ß and NSE, but not NGB, were significantly higher in the 15 patients who showed POCD than in the remainder who did not. For prediction of early POCD, S100ß showed an area under the receiver operating characteristic curve (AUC) of 0.71 (95% confidence interval [CI] 0.55-0.87), sensitivity of 48%, and specificity of 87%. The corresponding values for NSE were 0.77 (95%CI 0.60-0.94), 92%, and 67%. Together, S100ß and NSE showed an AUC of 0.81 (95%CI 0.66-0.96), sensitivity of 73%, and specificity of 80%. NGB did not significantly predict early POCD (AUC 0.62, 95%CI 0.43-0.80).Plasma S100ß protein and NSE, but not NGB, may help predict early POCD after total arch replacement.


Assuntos
Ponte Cardiopulmonar/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Neuroglobina/sangue , Fosfopiruvato Hidratase/sangue , Complicações Cognitivas Pós-Operatórias/etiologia , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Biomarcadores/sangue , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade
6.
Molecules ; 26(8)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924212

RESUMO

Neuroglobin (NGB) is a myoglobin-like monomeric globin that is involved in several processes, displaying a pivotal redox-dependent protective role in neuronal and extra-neuronal cells. NGB remarkably exerts its function upon upregulation by NGB inducers, such as 17ß-estradiol (E2) and H2O2. However, the molecular bases of NGB's functions remain undefined, mainly in non-neuronal cancer cells. Human MCF-7 breast cancer cells with a knocked-out (KO) NGB gene obtained using CRISPR/Cas9 technology were analyzed using shotgun label-free quantitative proteomics in comparison with control cells. The differential proteomics experiments were also performed after treatment with E2, H2O2, and E2 + H2O2. All the runs acquired using liquid chromatography-tandem mass spectrometry were elaborated within the same MaxQuant analysis, leading to the quantification of 1872 proteins in the global proteomic dataset. Then, a differentially regulated protein dataset was obtained for each specific treatment. After the proteomic study, multiple bioinformatics analyses were performed to highlight unbalanced pathways and processes. Here, we report the proteomic and bioinformatic investigations concerning the effects on cellular processes of NGB deficiency and cell treatments. Globally, the main processes that were affected were related to the response to stress, cytoskeleton dynamics, apoptosis, and mitochondria-driven pathways.


Assuntos
Neoplasias da Mama/genética , Neuroglobina/genética , Estresse Oxidativo/genética , Proteômica , Apoptose/genética , Neoplasias da Mama/patologia , Biologia Computacional , Receptor alfa de Estrogênio/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Inativação de Genes , Humanos , Células MCF-7 , Proteínas de Neoplasias/genética
7.
Arch Biochem Biophys ; 701: 108823, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33675812

RESUMO

Dysfunctional mitochondria have severe consequences on cell functions including Reactive Oxygen Specie (ROS) generation, alteration of mitochondrial signaling, Ca2+ buffering, and activation of apoptotic pathway. These dysfunctions are closely linked with degenerative diseases including neurodegeneration. The discovery of neuroglobin (NGB) as an endogenous neuroprotective protein, which effects seem to depend on its mitochondrial localization, could drive new therapeutic strategies against aged-related neurodegenerative diseases. Indeed, high levels of NGB are active against several brain injuries, including neurodegeneration, hypoxia, ischemia, toxicity, and nutrient deprivation opening a new scenario in the comprehension of the relationship between neural pathologies and mitochondrial homeostasis. In this review, we provide the current understanding of the role of mitochondria in neurodegeneration and discuss structural and functional connection between NGB and mitochondria with the purpose of defining a novel mitochondrial-based neuroprotective mechanism(s).


Assuntos
Sinalização do Cálcio , Cálcio/metabolismo , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/metabolismo , Neuroglobina/metabolismo , Neuroproteção , Animais , Humanos , Mitocôndrias/patologia , Doenças Neurodegenerativas/patologia
8.
Inorg Chem ; 60(4): 2839-2845, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33539081

RESUMO

Protein design has received much attention in the last decades. With an additional disulfide bond to enhance the protein stability, human A15C neuroglobin (Ngb) is an ideal protein scaffold for heme enzyme design. In this study, we rationally converted A15C Ngb into a multifunctional peroxidase by replacing the heme axial His64 with an Asp residue, where Asp64 and the native Lys67 at the heme distal site were proposed to act as an acid-base catalytic couple for H2O2 activation. Kinetic studies showed that the catalytic efficiency of A15C/H64D Ngb was much higher (∼50-80-fold) than that of native dehaloperoxidase, which even exceeds (∼3-fold) that of the most efficient native horseradish peroxidase. Moreover, the dye-decolorizing peroxidase activity was also comparable to that of some native enzymes. Electron paramagnetic resonance, molecular docking, and isothermal titration calorimetry studies provided valuable information for the substrate-protein interactions. Therefore, this study presents the rational design of an efficient multifunctional peroxidase based on Ngb with potential applications such as in bioremediation for environmental sustainability.


Assuntos
Neuroglobina/química , Peroxidase/química , Cristalografia por Raios X , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Simulação de Acoplamento Molecular , Conformação Proteica
9.
Environ Toxicol Pharmacol ; 84: 103604, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33545379

RESUMO

People who drink water contaminated with arsenic for a long time develop neuritis, cerebellar symptoms, and deficits in memory and intellectual function. Arsenic induces oxidative stress and promotes apoptosis through multiple signalling pathways in nerve cells. Neuroglobin (Ngb), as a key mediator, is considered to be protective against oxidative stress. In this study, we aimed to study the effects of Ngb knockdown in arsenite-treated rat neurons on levels of apoptosis markers and reactive oxygen species and serum Ngb levels of subjects from arsenic-endemic regions in China. We discovered that arsenic-induced apoptosis and reactive oxygen species production were enhanced in Ngb-knocked-down rat neurons. Silencing of Ngb aggravated the arsenic-induced decrease in the rate of Bcl-2/Bax and the levels of Bcl-2 protein following arsenite treatment. The results also showed that serum Ngb levels were independently negatively correlated with arsenic concentration in drinking water. Furthermore, the serum Ngb levels of four groups (245 individuals) according to different degree exposure to arsenic were 815.18 ± 89.52, 1247.97 ± 117.18, 774.79 ± 91.55, and 482.72 ± 49.30 pg/mL, respectively. Taken together, it can be deduced that Ngb has protective effects against arsenic-induced apoptosis by eliminating reactive oxygen species.


Assuntos
Arsênio/toxicidade , Neuroglobina/sangue , Neurônios/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Idoso , Animais , Apoptose/efeitos dos fármacos , Arsênio/análise , Células Cultivadas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroglobina/genética , Neurônios/metabolismo , Síndromes Neurotóxicas/sangue , Estresse Oxidativo/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Interferente Pequeno/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Poluentes Químicos da Água/análise
10.
Free Radic Biol Med ; 162: 471-477, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166649

RESUMO

Neuroglobin is the third member of the globin family to be identified in 2000 in neurons of both human and mouse nervous systems. Neuroglobin is an oxygen-binding globin found in neurons within the central nervous system as well as in peripheral neurons, that produces a protective effect against hypoxic/ischemic damage induced by promoting oxygen availability within the mitochondria. Numerous investigations have demonstrated that impaired neuroglobin functioning is implicated in the pathogenesis of multiple neurodegenerative disorders. Several in vitro and animal studies have reported the potential of neuroglobin upregulation in improving the neuroprotection through modulation of mitochondrial functions, such as ATP production, clearing reactive oxygen species (ROS), promoting the dynamics of mitochondria, and controlling apoptosis. Neuroglobin acts as a stress-inducible globin, which has been associated hypoxic/ischemic insults where it acts to protect the heart and brain, providing a wide range of applicability in the treatment of human disorders. This review article discusses normal physiological functions of neuroglobin in mitochondria-associated pathways, as well as outlining how dysregulation of neuroglobin is associated with the pathogenesis of neurodegenerative disorders.


Assuntos
Proteínas do Tecido Nervoso , Doenças Neurodegenerativas , Animais , Globinas/genética , Mitocôndrias , Proteínas do Tecido Nervoso/genética , Doenças Neurodegenerativas/tratamento farmacológico , Neuroglobina
11.
Phys Chem Chem Phys ; 22(35): 19982-19991, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32869045

RESUMO

We report the observation of electron spin polarization transfer from the triplet state of a porphyrin to a weakly coupled nitroxide radical in a mutant of human neuroglobin (NGB). The native iron-containing heme substrate of NGB has been substituted with Zn(ii) protoporphyrin IX and the nitroxide has been attached via site-directed spin labeling to the Cys120 residue. A reference synthetic polypeptide with free base tetraphenylporphyrin and a nitroxide bound to it is also studied. In both systems the nitroxide and the porphyrin are held at a fixed distance of approximately 2.4 nm. The transient EPR data of the NGB sample show that the triplet state of Zn(ii) protoporphyrin acquires significant net polarization, which is attributed to the dynamic Jahn-Teller effect. As the spin polarization of the protoporphyrin triplet state decays, a polarized EPR signal of the nitroxide arises. In contrast, the free base porphyrin in the reference polypeptide does not acquire net polarization and no polarization of the nitroxide label is observed. This is likely a result of the fact that the porphyrin is not Jahn-Teller active because of its lower symmetry. A perturbation theory treatment suggests that in the NGB sample, the polarization of the radical occurs by the transfer of net polarization from the triplet state. This process is also enhanced by the spectral broadening caused by the back and forth transitions associated with the dynamic Jahn-Teller effect. We propose that the novel transfer of polarization to the radical could be exploited to enhance the sensitivity of light-induced dipolar spectroscopy experiments.


Assuntos
Radicais Livres/química , Neuroglobina/química , Óxidos N-Cíclicos/química , Cisteína/química , Espectroscopia de Ressonância de Spin Eletrônica , Humanos , Mesilatos/química , Protoporfirinas/química , Marcadores de Spin
12.
Redox Biol ; 37: 101687, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32863222

RESUMO

Vertebrate hemoglobin (Hb) and myoglobin (Mb) were among the first proteins whose structures and sequences were determined over 50 years ago. In the subsequent pregenomic period, numerous related proteins came to light in plants, invertebrates and bacteria, that shared the myoglobin fold, a signature sequence motif characteristic of a 3-on-3 α-helical sandwich. Concomitantly, eukaryote and bacterial globins with a truncated 2-on-2 α-helical fold were discovered. Genomic information over the last 20 years has dramatically expanded the list of known globins, demonstrating their existence in a limited number of archaeal genomes, a majority of bacterial genomes and an overwhelming majority of eukaryote genomes. In vertebrates, 6 additional globin types were identified, namely neuroglobin (Ngb), cytoglobin (Cygb), globin E (GbE), globin X (GbX), globin Y (GbY) and androglobin (Adgb). Furthermore, functions beyond the familiar oxygen transport and storage have been discovered within the vertebrate globin family, including NO metabolism, peroxidase activity, scavenging of free radicals, and signaling functions. The extension of the knowledge on globin functions suggests that the original roles of bacterial globins must have been enzymatic, involved in defense against NO toxicity, and perhaps also as sensors of O2, regulating taxis away or towards high O2 concentrations. In this review, we aimed to discuss the evolution and remarkable functional diversity of vertebrate globins with particular focus on the variety of non-canonical expression sites of mammalian globins and their according impressive variability of atypical functions.


Assuntos
Evolução Molecular , Genômica , Globinas , Animais , Citoglobina , Globinas/genética , Neuroglobina , Oxigênio , Vertebrados
13.
J Mol Neurosci ; 70(12): 1943-1961, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32621100

RESUMO

The study investigated the potential neuroprotective effects of metformin (MET) on alcohol-induced neurotoxicity in adult Wistar rats. The animals were randomized in four groups (n = 10): control, alcohol (ALC), ALC + MET, and MET. ALC (2 g/kg b.w.) and MET (200 mg/kg b.w.) were orally administered for 21 days, once daily. For the ALC + MET group, MET was administered 2 h after ALC treatment. On day 22, the open field test (OFT) and elevated plus maze (EPM) were performed. MET improved global activity and increased the time spent in unprotected open arms, decreased oxidative stress, both in the frontal lobe and in the hippocampus, and increased neuroglobin expression in the frontal cortex. Histopathologically, an increased neurosecretory activity in the frontal cortex in the ALC + MET group was noticed. Thus, our findings suggest that metformin has antioxidant and anxiolytic effects and may partially reverse the neurotoxic effects induced by ethanol.


Assuntos
Antioxidantes/farmacologia , Ansiedade/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Matriz Extracelular/metabolismo , Metformina/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Antioxidantes/uso terapêutico , Ansiedade/etiologia , Encéfalo/metabolismo , Etanol/toxicidade , Matriz Extracelular/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto , Metformina/uso terapêutico , Neuroglobina/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Estresse Oxidativo , Ratos , Ratos Wistar
14.
Mol Biol (Mosk) ; 54(3): 474-479, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32492011

RESUMO

The iron-containing protein neuroglobin (Ngb) involved in the transport of oxygen is generally considered the precursor of all animal globins. In this report, we studied the structure of Ngb of the cold-water sponge Halisarca dujardinii. In sponges, the oldest multicellular organisms, the Ngb gene contains three introns. In contrast to human Ngb, its promoter contains a TATA-box, rather than CG-rich motifs. In sponges, Ngb consists of 169 amino acids showing rather low similarity with its mammalian orthologues. It lacks Glu and Arg residues in positions required for prevention of hypoxia-related apoptosis. Nevertheless, Ngb contains both proximal and distal conserved heme-biding histidines. The primary structure of H. dujardinii neuroglobin predicted by sequencing was confirmed by mass-spectrometry analysis of recombinant Ngb expressed in E. coli. The high level of Ngb expression in sponge tissues suggests its possible involvement in the gas metabolism and presumably in other key metabolic processes in H. dujardinii.


Assuntos
Neuroglobina/química , Poríferos/química , Aminoácidos , Animais , Escherichia coli , Íntrons , Regiões Promotoras Genéticas
15.
Eur J Neurosci ; 52(1): 2756-2770, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32243028

RESUMO

Including sex is of paramount importance in preclinical and clinical stroke researches, and molecular studies dealing in depth with sex differences in stroke pathophysiology are needed. To gain insight into the molecular sex dimorphism of ischaemic stroke in rat cerebral cortex, male and female adult rats were subjected to transient middle cerebral artery occlusion. The expression of neuroglobin (Ngb) and other functionally related molecules involved in sex steroid signalling (oestrogen and androgen receptors), steroidogenesis (StAR, TSPO and aromatase) and autophagic activity (LC3B-II/LC3B-I ratio, UCP2 and HIF-1α) was assessed in the ipsilateral ischaemic and contralateral non-ischaemic hemispheres. An increased expression of Ngb was detected in the injured female cerebral cortex. In contrast, increased expression of oestrogen receptor α, GPER, StAR, TSPO and UCP2, and decreased androgen receptor expression were detected in the injured male cortex. In both sexes, the ischaemic insult induced an upregulation of LC3B-II/-I ratio, indicative of increased autophagy. Therefore, the cerebral cortex activates both sex-specific and common molecular responses with neuroprotective potential after ischaemia-reperfusion, which globally results in similar stroke outcome in both sexes. Nonetheless, these different potential molecular targets should be taken into account when neuroprotective drugs aiming to reduce brain damage in ischaemic stroke are investigated.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Autofagia , Córtex Cerebral , Modelos Animais de Doenças , Feminino , Infarto da Artéria Cerebral Média , Masculino , Neuroglobina , Ratos , Ratos Sprague-Dawley , Caracteres Sexuais , Esteroides
16.
J Biol Chem ; 295(19): 6357-6371, 2020 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-32205448

RESUMO

Carbon monoxide (CO) remains the most common cause of human poisoning. The consequences of CO poisoning include cardiac dysfunction, brain injury, and death. CO causes toxicity by binding to hemoglobin and by inhibiting mitochondrial cytochrome c oxidase (CcO), thereby decreasing oxygen delivery and inhibiting oxidative phosphorylation. We have recently developed a CO antidote based on human neuroglobin (Ngb-H64Q-CCC). This molecule enhances clearance of CO from red blood cells in vitro and in vivo Herein, we tested whether Ngb-H64Q-CCC can also scavenge CO from CcO and attenuate CO-induced inhibition of mitochondrial respiration. Heart tissue from mice exposed to 3% CO exhibited a 42 ± 19% reduction in tissue respiration rate and a 33 ± 38% reduction in CcO activity compared with unexposed mice. Intravenous infusion of Ngb-H64Q-CCC restored respiration rates to that of control mice correlating with higher electron transport chain CcO activity in Ngb-H64Q-CCC-treated compared with PBS-treated, CO-poisoned mice. Further, using a Clark-type oxygen electrode, we measured isolated rat liver mitochondrial respiration in the presence and absence of saturating solutions of CO (160 µm) and nitric oxide (100 µm). Both CO and NO inhibited respiration, and treatment with Ngb-H64Q-CCC (100 and 50 µm, respectively) significantly reversed this inhibition. These results suggest that Ngb-H64Q-CCC mitigates CO toxicity by scavenging CO from carboxyhemoglobin, improving systemic oxygen delivery and reversing the inhibitory effects of CO on mitochondria. We conclude that Ngb-H64Q-CCC or other CO scavengers demonstrate potential as antidotes that reverse the clinical and molecular effects of CO poisoning.


Assuntos
Intoxicação por Monóxido de Carbono/metabolismo , Monóxido de Carbono/toxicidade , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Hepáticas/metabolismo , Neuroglobina/metabolismo , Animais , Intoxicação por Monóxido de Carbono/patologia , Carboxihemoglobina/metabolismo , Humanos , Masculino , Camundongos , Mitocôndrias Cardíacas/patologia , Mitocôndrias Hepáticas/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico/farmacologia , Consumo de Oxigênio/efeitos dos fármacos , Ratos
17.
Brain Behav ; 10(3): e01547, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32026621

RESUMO

BACKGROUND: The neuroglobin (Ngb) is well recognized as a potential biomarker for the hypoxic-ischemic brain injury. However, connection between Ngb and delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) is still unclear. OBJECTIVE: To investigate the relationship between early stage Ngb level of aSAH patient and the occurrence of DCI. METHODS: We evaluated 126 aSAH patients who were enrolled into a prospective observational cohort study. Serum Ngb level on days 1, 2, 3, 5, and 7 after aSAH were determined using a commercial enzyme-linked immunosorbent assay kit. The relationship between Ngb level and DCI was analyzed. RESULTS: Forty-six (36.5%) aSAH patients experienced DCI. Patients with DCI had significantly higher Ngb levels than those without (p < .001). Multivariate model analysis revealed that day 3 Ngb level remained a significant factor after adjusting for World Federation of Neurosurgical Societies (WFNS) grade, modified Fisher grade, clipping and Ngb levels on days 1, 2, 5, and 7. Sensitivity, specificity, and Youden index of day 3 Ngb level for identifying DCI were derived as 73.9%, 72.5%, and 0.46, respectively, based on the best threshold of 8.4 ng/ml. Regardless in good-grade group or in poor-grade group, patients having day 3 Ngb level > 8.4 ng/ml has a significantly worse DCI survival rate than those having day 3 Ngb level <=8.4 ng/ml (p = .026 and .009, respectively). CONCLUSIONS: Serum Ngb level was significantly elevated in DCI patients. Early stage aSAH Ngb level has the potential of being used as a novel DCI occurrence predictor, especially when Ngb level was combined with WFNS grade.


Assuntos
Isquemia Encefálica/diagnóstico , Neuroglobina/sangue , Hemorragia Subaracnóidea/complicações , Adulto , Idoso , Biomarcadores/sangue , Isquemia Encefálica/sangue , Isquemia Encefálica/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Hemorragia Subaracnóidea/sangue
18.
FEBS J ; 287(18): 4082-4097, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32034988

RESUMO

Different murine neuroglobin variants showing structural and dynamic alterations that are associated with perturbation of ligand binding have been studied: the CD loop mutants characterized by an enhanced flexibility (Gly-loop40-48 and Gly-loop44-47 ), the F106A mutant, and the double Gly-loop44-47 /F106A mutant. Their ferric resonance Raman spectra in solution and in crystals are almost identical. In the high-frequency region, the identification of a double set of core size marker bands indicates the presence of two 6-coordinate low spin species. The resonance Raman data, together with the corresponding crystal structures, indicate the presence of two neuroglobin conformers with a reversed (A conformer) or a canonical (B conformer) heme insertion orientation. With the identification of the marker bands corresponding to each conformer, the data indicate that the B conformer increases at the expense of the A form, predominantly in the Gly-loop44-47 /F106A double mutant, as confirmed by X-ray crystallography. This is the first time that a reversed heme insertion has been identified by resonance Raman in a native 6-coordinate low-spin heme protein. This diagnostic tool could be extended to other heme proteins in order to detect heme orientational disorder, which are likely to be correlated to functionally relevant heme dynamics. DATABASE: Crystallographic structure: structural data are deposited in the Protein Data Bank under the 6RA6 PDB entry.


Assuntos
Heme/química , Neuroglobina/química , Conformação Proteica , Análise Espectral Raman/métodos , Sequência de Aminoácidos , Animais , Cristalografia por Raios X , Heme/metabolismo , Camundongos , Neuroglobina/genética , Neuroglobina/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos
19.
Biochem Biophys Res Commun ; 523(3): 567-572, 2020 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-31937411

RESUMO

Neuroglobin is a heme protein present in the nervous system cells of mammals and other organisms. Although cytoprotective effects of neuroglobin on neuronal damage have been reported, the physiological mechanisms of neuroglobin function remain unknown. In recent years, a role for neuroglobin as a reductant for extramitochondrial cytochrome c has been proposed. According to this hypothesis, cytoplasmic neuroglobin can interact with cytochrome c released from the mitochondria and reduce its heme group to the ferrous state, thus preventing cytochrome c-dependent assembly of the apoptosome. The interaction of neuroglobin and cytochrome c has been studied by surface plasmon resonance techniques and molecular dynamics, however the empirical evidence on the specific residues of neuroglobin and cytochrome c involved in the interaction is scarce and indirect. This study analyzes the role of five negatively charged residues in the neuroglobin surface putatively involved in the interaction with cytochrome c - Glu60, Asp63, Asp73, Glu 87 and Glu151 - by site-directed mutagenesis. Characterization of the electron transfer between neuroglobin mutants and cytochrome c indicates that Asp73 is critical for the interaction, and Glu60, Asp63 and Glu87 also contribute to the neuroglobin-cytochrome c interaction. Based on the results, structures and binding surfaces for the neuroglobin-cytochrome c complex compatible with the experimental observations are proposed. These data can guide further studies on neuroglobin function and its involvement in cytochrome c signaling cascades.


Assuntos
Citocromos c/metabolismo , Neuroglobina/metabolismo , Animais , Apoptose , Apoptossomas/metabolismo , Sítios de Ligação , Citocromos c/química , Transporte de Elétrons , Cavalos , Simulação de Acoplamento Molecular , Neuroglobina/química , Ligação Proteica , Mapas de Interação de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Eletricidade Estática
20.
Mar Genomics ; 49: 100724, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31735579

RESUMO

The ancient origins and functional versatility of globins make them ideal subjects for studying physiological adaptation to environmental change. Our goals in this review are to describe the evolution of the vertebrate globin gene superfamily and to explore the structure/function relationships of hemoglobin, myoglobin, neuroglobin and cytoglobin in teleost fishes. We focus on the globins of Antarctic notothenioids, emphasizing their adaptive features as inferred from comparisons with human proteins. We dedicate this review to Guido di Prisco, our co-author, colleague, friend, and husband of C.V. Ever thoughtful, creative, and enthusiastic, Guido spearheaded study of the structure, function, and evolution of the hemoglobins of polar fishes - this review is testimony to his wide-ranging contributions. Throughout his career, Guido inspired younger scientists to embrace polar biological research, and he challenged researchers of all ages to explore evolutionary adaptation in the context of global climate change. Beyond his scientific contributions, we will miss his warmth, his culture, and his great intellect. Guido has left an outstanding legacy, one that will continue to inspire us and our research.


Assuntos
Adaptação Fisiológica , Evolução Molecular , Peixes/genética , Globinas/genética , Sequência de Aminoácidos , Animais , Regiões Antárticas , Citoglobina/genética , Hemoglobinas/genética , Família Multigênica , Mioglobina/genética , Neuroglobina/genética , Sintenia
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