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Muhammad Shahdaat Bin Sayeed, Qasim Alhadidi, Zahoor A Shah
Intracerebral hemorrhage (ICH) is the most severe form of stroke and is further exacerbated by the secondary injury involving inflammatory response due to the activation of microglia. This secondary injury is partly due to the toxic effects of hemin, an endogenous breakdown product of hemoglobin. Cofilin, an actin depolymerizing factor, controls actin dynamics and has been previously shown to be involved in mediating neuronal cell death in ischemic conditions and during bacterial lipopolysaccharide induced microglial activation...
December 15, 2017: Journal of Neuroimmunology
Yubin Li, Sheng Liu, Qiujuan Deng, Liansheng Ling
A sensitive colorimetric DNA biosensor for specific detection of single stranded oligonucleotide (ssDNA) is proposed in this paper. The biosensor is based on silver-coated glass (SCGS) and G-quadruplex-hemin DNAzyme. Capture DNA is immobilized on the surface of SCGS by Ag-S bond. Signal DNA can be used to hybridize with the target DNA which is selected from the Hepatitis B virus(HBV) gene as target HBV DNA, and the HRP-mimicking G-quadruplex-hemin DNAzyme can be formed through the function of a guanine-rich fragment from signal DNA to catalyze the oxidation of 2,2-azinobis(3-ethylbenzothiozoline)-6-sulfonicacid (ABTS(2-) ) by H2 O2 ...
November 16, 2017: Journal of Medical Virology
Negar Alizadeh, Abdollah Salimi, Rahman Hallaj
Enzymes are macromolecular biological catalysts that accelerate chemical reactions. Enzyme labels are commonly used to obtain signal amplification in sensors and biosensors on the basis of reactions of some enzymes such as horseradish peroxidase (HRP). However, use of natural enzymes can encounter some challenges. Lately, nucleic acids that exhibit catalytic properties have attracted growing interest because they have certain advantages in comparison with traditional protein enzymes. DNAzymes are DNA-based catalysts, representing an important class of functional DNA, which have been widely used because of their excellent activity, programmability, signal amplification through catalytic turnover, high chemical stability, simple synthesis, and easy modification...
November 16, 2017: Advances in Biochemical Engineering/biotechnology
Nantawat Tatiyaborworntham, Mark P Richards
BACKGROUND: Hemoglobin is a lipid oxidation promoter in fish muscle. Phospholipase A2 (PLA2; EC, is linked to increased resistance to lipid oxidation of frozen-thawed cod fillets via an unknown mechanism. The aims of this study were to investigate the mechanism of hemoglobin-mediated lipid oxidation with a focus on ferryl hemoglobin and methemoglobin, the pro-oxidative hemoglobin species, and to examine how porcine pancreatic PLA2 inhibits hemoglobin-mediated lipid oxidation in washed cod muscle (WCM)...
November 13, 2017: Journal of the Science of Food and Agriculture
Ryo Yamauchi, Tomomi Kinoshita, Yoshinori Hasegawa, Satoshi Iwamoto
The secondary process of lipid peroxidation proceeds by the free radical reaction to produce some toxic aldehydes. Since γ-tocopherol (γ-TH), one of the major forms of vitamin E in some vegetable oils, acts as a free radical scavenger, γ-TH may suppress the formation of such aldehydes. This study reports the effect and reaction products of γ-TH on the hemin- or myoglobin-catalyzed decomposition of 1-palmitoyl-2-linoleoyl-3-sn-phosphatidylcholine 13-hydroperoxide (PLPC-OOH) in micelles and liposomes. γ-TH and PLPC-OOH in micelles were reacted in the presence of hemin, and the reaction products were characterized as 1-palmitoyl-2-[(8a-dioxy-γ-tocopherone)-12,13-epoxyoctadecenoyl]-3-sn-phosphatidylcholines (γT-OO-epoxyPLPC), 1-palmitoyl-2-[(γ-tocopheroxy)-12,13-epoxyoctadecenoyl]-3-sn-phosphatidylcholines (γT-epoxyPLPC), and the adducts of γ-TH dimer with PLPC-OOH derived epoxyperoxyl and epoxyalkyl radicals (γTD-OO-epoxyPLPC and γTD-epoxyPLPC)...
November 7, 2017: Chemistry and Physics of Lipids
Andres S Benitez Cardenas, Premila P Samuel, John S Olson
This article reviews the key biochemical mechanisms that govern O2 transport, NO scavenging, and oxidative degradation of acellular hemoglobin and how these ideas have been used to try to develop strategies to engineer safer and more effective hemoglobin-based oxygen carriers (HBOCs). Significant toxicities due to acellular hemoglobin (Hb) have been observed after the administration of HBOCs or after the lysis of red cells, and include: (a) rapid clearance and kidney damage due to dissociation into dimers, haptoglobin binding, and macrophage activation; (b) early O2 release leading to decreased tissue perfusion in capillary beds; (c) interference with endothelial and smooth muscle signaling due to nitric oxide (NO) scavenging; (d) autooxidization of heme iron followed by production of reactive oxygen species; and (e) iron overload symptoms due to hemin loss, globin denaturation, iron accumulation, and further inflammation...
November 6, 2017: Shock
Ferenc Zsila, Tünde Juhász, Szilvia Bősze, Kata Horváti, Tamás Beke-Somfai
The interaction of protoporphyrin compounds of human origin with the major bee venom component melittin (26 a.a., Z +6) and its hybrid derivative (CM15, 15 a.a., Z +6) were studied by a combination of various spectroscopic methods. Throughout a two-state, concentration-dependent process, hemin and its metabolites (biliverdin, bilirubin, bilirubin ditaurate) increase the parallel β-sheet content of the natively unfolded melittin, suggesting the oligomerization of the peptide chains. In contrast, α-helix promoting effect was observed with the also disordered but more cationic CM15...
November 7, 2017: Chirality
Huangxian Ju, Yuehua Guo, Jielin Chen, Mingpan Cheng, David Monchaud, Jun Zhou
Quadruplex-based DNAzyme system is one of the most useful artificial enzymes or catalysts due to their unique properties that make them reliable alternatives to proteins for performing catalytic transformation. Herein, we report on the first prototype of a thermally stable DNAzyme system, referred to as a thermophilic DNAzyme, capable of oxidizing substrates in harsh experimental conditions, i.e., high temperature (up to 95 °C) and long reaction times (up to 18 h at 75 °C). The step-by-step design of this unique heat-activated G-quadruplex/hemin catalyst, including the modification of adenines at both ends of G-tracts, the choice of cation and its concentration for DNAzyme stabilization, is described...
November 6, 2017: Angewandte Chemie
V R Souza Júnior, V M V Lemos, I M L Feitosa, R Florencio, C W B Correia, L B Correia Fontes, M F Hazin Costa, M C B Correia
A 16-year-old female who was attended as an outpatient reported localized, acute abdominal pain with vomiting, symmetrical motor weakness, and burning sensation in both arms and legs. Her medical history showed irrational behavior, repeated admissions at the emergency units of many other reference hospitals, where she had been investigated for celiac disease and treated with analgesics for pain events. Her clinical condition remained unchanged despite the use of many oral analgesics. In those admissions, she showed dysautonomia, vomiting, and abdominal pain...
January 2017: Child neurology open
Eun Jung Park, Young Min Kim, Ki Churl Chang
BACKGROUND AND AIMS: High mobility group box 1 (HMGB1) plays an important role as a pro-inflammatory cytokine that regulates inflammation in various diseases. We hypothesized that hemin might reduce HMGB1 release through the induction of HO-1 in UVB-induced HaCaTs. METHODS: The effects of hemin on the release of HMGB1 in UVB exposure were evaluated. The mechanisms were investigated using various signal inhibitors and small interfering RNA techniques. RESULTS: Treatment with hemin inhibited reactive oxygen species (ROS) in UVB-induced HaCaTs in a dose-dependent manner...
October 28, 2017: Archives of Medical Research
Yong Yang, Zhiyu Xi, Yuan Xue, Jie Ren, Yuhao Sun, Baofeng Wang, Zhihong Zhong, Guo-Yuan Yang, Qingfang Sun, Liuguan Bian
Oxidative stress mediated secondary injury contributes to neurological deterioration after intracerebral hemorrhage (ICH). Astrocytes, the most dominant cells in the central nervous system (CNS), play key roles in maintaining redox homeostasis by providing oxidative stress defense. Hemoglobin (Hb), the primary component released by hemolysis, is an effective activator of astrocytes. Hemin, the product of Hb degradation, is highly toxic due to the induction of reactive oxygen species (ROS). We speculate that Hb-activated astrocytes are resistant to hemin-induced toxicity...
October 24, 2017: Experimental Cell Research
Jinting Gao, Yaqing Liu, Xiaodong Lin, Jiankang Deng, Jinjin Yin, Shuo Wang
Wiring a series of simple logic gates to process complex data is significantly important and a large challenge for untraditional molecular computing systems. The programmable property of DNA endows its powerful application in molecular computing. In our investigation, it was found that DNA exhibits excellent peroxidase-like activity in a colorimetric system of TMB/H2O2/Hemin (TMB, 3,3', 5,5'-Tetramethylbenzidine) in the presence of K(+) and Cu(2+), which is significantly inhibited by the addition of an antioxidant...
October 25, 2017: Scientific Reports
Michael Brad Strader, Rachel Bangle, Claire J Parker Siburt, Cornelius L Varnado, Jayashree Soman, Andres S Benitez Cardenas, Premila S Samuel, Eileen W Singleton, Alvin L Crumbliss, John S Olson, Abdu I Alayash
Previous work suggested that hemoglobin (Hb) tetramer formation slows autoxidation and hemin loss and that the naturally occurring mutant, Hb Providence (βK82D) is much more resistant to degradation by H2O2 We have examined systematically the effects of genetic crosslinking of Hb tetramers with and without the Hb Providence mutation on autoxidation, hemin loss, and reactions with H2O2, using native HbA and various wild-type recombinant Hbs as controls. Genetically crosslinked Hb Presbyterian (βN108K) was also examined as an example of a low oxygen affinity tetramer...
October 25, 2017: Biochemical Journal
Witold Norbert Nowak, Hevidar Taha, Neli Kachamakova-Trojanowska, Jacek Stepniewski, Joanna Agata Markiewicz, Anna Kusienicka, Krzysztof Szade, Agata Szade, Karolina Bukowska-Strakova, Karolina Hajduk, Damian Klóska, Aleksandra Kopacz, Anna Grochot-Przeczek, Kathrin Barthenheier, Camille Cauvin, Jozef Dulak, Alicja Jozkowicz
AIMS: Mesenchymal stromal cells (MSCs) are heterogeneous cells from adult tissues, able to differentiate in vitro into adipocytes, osteoblasts or chondrocytes. Such cells are widely studied in regenerative medicine. However, the success of cellular therapy depends on the cell survival. Heme oxygenase-1 (HO-1, encoded by the Hmox1 gene), an enzyme converting heme to biliverdin, carbon monoxide, and Fe2+, is cytoprotective and can affect stem cell performance. Therefore, our study aimed to assess if Hmox1 is critical for survival and functions of murine bone marrow MSCs...
October 25, 2017: Antioxidants & Redox Signaling
Kangyao Zhang, Shuzhen Lv, Zhenzhen Lin, Meijin Li, Dianping Tang
Methods based on photoelectrochemistry have been developed for immunoassay, but most involve in a low sensitivity and a relatively narrow detectable range. Herein a new bio-bar-code-based split-type photoelectrochemical (PEC) immunoassay was designed for sensitive detection of prostate-specific antigen (PSA), coupling rolling circle amplification (RCA) with enzymatic biocatalytic precipitation. The bio-bar-code-based immunoreaction was carried out on monoclonal anti-PSA antibody (mAb1)-coated microplate using primer DNA and polyclonal anti-PSA antibody-conjugated gold nanoparticle (pDNA-AuNP-pAb2) with a sandwich-type assay format...
October 16, 2017: Biosensors & Bioelectronics
Haitang Yang, Anran Liu, Min Wei, Yuanjian Liu, Bingjing Lv, Wei Wei, Yuanjian Zhang, Songqin Liu
Early diagnosis and life-long surveillance are clinically important to improve the long-term survival of cancer patients. Telomerase activity is a valuable biomarker for cancer diagnosis, but its measurement often used complex label procedures. Herein, we designed a novel, simple, visual and label-free method for telomerase detection by using enzymatic etching of gold nanorods (GNRs). First, repeating (TTAGGG)x sequences were extented on telomerase substrate (TS) primer. It formed G-quadruplex under the help of Hemin and K(+)...
November 3, 2017: Analytical Chemistry
Jonas Fyrestam, Conny Östman
One of the main threats to the achievements in modern medicine is antimicrobial resistance. Molecular targeting of bacterial acquisition mechanisms of heme has been suggested to be an alternative to antibiotics. In the present study, HPLC-MS/MS combined with a simple clean-up based on liquid-liquid extraction has been developed and evaluated for simultaneous determination of heme and porphyrin heme precursors in microorganisms. Experimental design was used to optimize the extraction parameters, to obtain a method with high recovery, low matrix effects, and high precision...
October 17, 2017: Analytical and Bioanalytical Chemistry
Fabiana Zolea, Anna Martina Battaglia, Emanuela Chiarella, Donatella Malanga, Carmela De Marco, Heather Mandy Bond, Giovanni Morrone, Francesco Costanzo, Flavia Biamonte
Erythroid differentiation is a complex and multistep process during which an adequate supply of iron for hemoglobinization is required. The role of ferritin heavy subunit, in this process, has been mainly attributed to its capacity to maintain iron in a non-toxic form. We propose a new role for ferritin heavy subunit (FHC) in controlling the erythroid commitment of K562 erythro-myeloid cells. FHC knockdown induces a change in the balance of GATA transcription factors and significantly reduces the expression of a repertoire of erythroid-specific genes, including α- and γ-globins, as well as CD71 and CD235a surface markers, in the absence of differentiation stimuli...
October 17, 2017: International Journal of Molecular Sciences
Ye Tao, Zhao Ma, Bei Liu, Wei Fang, Limin Qin, Yi Fei Huang, Lu Wang, Yanling Gao
Retina is a critical component of the central nerve system that is responsible for the conversion of light stimulus into electrical spikes. Retinitis pigmentosa (RP) comprises a heterogeneous group of inherited retinal dystrophies leading to blindness. We examined retinal neuroglobin (Ngb) expression in a pharmacologically induced RP animal model, the N-Methyl-N-nitrosourea (MNU) administered mice. The retinal Ngb expression in MNU administered mice attenuated following a time dependent manner, suggesting Ngb was involved in the photoreceptor degeneration...
October 13, 2017: Brain Research
Yingchun Gu, Dayong Lin, Yalin Tang, Xuening Fei, Cuihong Wang, Baolian Zhang, Jianguo Zhou
As its significant role, the selective recognition of G-quadruplex with specific structures and functions is important in biological and medicinal chemistry. Carbazole derivatives have been reported as a kind of fluorescent probe with many excellent optical properties. In the present study, the fluorescence of the dye (carbazole TO) increased almost 70 fold in the presence of bcl-2 2345 G4 compared to that alone in aqueous buffer condition with almost no fluorescence and 10-30 fold than those in the presence of other DNAs...
October 4, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
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