Academic literature on the topic 'Zinc Histidine'
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Journal articles on the topic "Zinc Histidine"
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Petrarca, Patrizia, Serena Ammendola, Paolo Pasquali, and Andrea Battistoni. "The Zur-Regulated ZinT Protein Is an Auxiliary Component of the High-Affinity ZnuABC Zinc Transporter That Facilitates Metal Recruitment during Severe Zinc Shortage." Journal of Bacteriology 192, no. 6 (January 22, 2010): 1553–64. http://dx.doi.org/10.1128/jb.01310-09.
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ABSTRACT The pathways ensuring the efficient uptake of zinc are crucial for the ability of bacteria to multiply in the infected host. To better understand bacterial responses to zinc deficiency, we have investigated the role of the periplasmic protein ZinT in Salmonella enterica serovar Typhimurium. We have found that zinT expression is regulated by Zur and parallels that of ZnuA, the periplasmic component of the zinc transporter ZnuABC. Despite the fact that ZinT contributes to Salmonella growth in media containing little zinc, disruption of zinT does not significantly affect virulence in mice. The role of ZinT became clear using strains expressing a mutated form of ZnuA lacking a characteristic histidine-rich domain. In fact, Salmonella strains producing this modified form of ZnuA exhibited a ZinT-dependent capability to import zinc either in vitro or in infected mice, suggesting that ZinT and the histidine-rich region of ZnuA have redundant function. The hypothesis that ZinT and ZnuA cooperate in the process of zinc recruitment is supported by the observation that they form a stable binary complex in vitro. Although the presence of ZinT is not strictly required to ensure the functionality of the ZnuABC transporter, our data suggest that ZinT facilitates metal acquisition during severe zinc shortage.
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Jiang, Qian, Andrew M. Peterson, Yuyang Chu, Xiaolan Yao, Xiang-ming Zha, and Xiang-Ping Chu. "Histidine Residues Are Responsible for Bidirectional Effects of Zinc on Acid-Sensing Ion Channel 1a/3 Heteromeric Channels." Biomolecules 10, no. 9 (September 2, 2020): 1264. http://dx.doi.org/10.3390/biom10091264.
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Acid-sensing ion channel (ASIC) subunits 1a and 3 are highly expressed in central and peripheral sensory neurons, respectively. Endogenous biomolecule zinc plays a critical role in physiological and pathophysiological conditions. Here, we found that currents recorded from heterologously expressed ASIC1a/3 channels using the whole-cell patch-clamp technique were regulated by zinc with dual effects. Co-application of zinc dose-dependently potentiated both peak amplitude and the sustained component of heteromeric ASIC1a/3 currents; pretreatment with zinc between 3 to 100 µM exerted the same potentiation as co-application. However, pretreatment with zinc induced a significant inhibition of heteromeric ASIC1a/3 channels when zinc concentrations were over 250 µM. The potentiation of heteromeric ASIC1a/3 channels by zinc was pH dependent, as zinc shifted the pH dependence of ASIC1a/3 currents from a pH50 of 6.54 to 6.77; whereas the inhibition of ASIC1a/3 currents by zinc was also pH dependent. Furthermore, we systematically mutated histidine residues in the extracellular domain of ASIC1a or ASIC3 and found that histidine residues 72 and 73 in both ASIC1a and ASIC3, and histidine residue 83 in the ASIC3 were responsible for bidirectional effects on heteromeric ASIC1a/3 channels by zinc. These findings suggest that histidine residues in the extracellular domain of heteromeric ASIC1a/3 channels are critical for zinc-mediated effects.
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Fujiwara, Tamaki, Shin Aoki, Hitoshi Komatsuzawa, Tetsuya Nishida, Masaru Ohara, Hidekazu Suginaka, and Motoyuki Sugai. "Mutation Analysis of the Histidine Residues in the Glycylglycine Endopeptidase ALE-1." Journal of Bacteriology 187, no. 2 (January 15, 2005): 480–87. http://dx.doi.org/10.1128/jb.187.2.480-487.2005.
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ABSTRACT A novel staphylolytic enzyme, ALE-1, is a glycylglycine endopeptidase produced by Staphylococcus capitis EPK1. ALE-1 possesses seven histidines. Chemical modification studies using diethylpyrocarbonate and iodoacetic acid suggested that a histidine or tyrosine residue(s) in the molecule is important for the organism's staphylolytic activity. All of the histidine residues, one tyrosine, and one aspartic acid residue in the N-terminally truncated ALE-1 (ΔN-term ALE-1) were systematically altered by site-directed mutagenesis, and the enzyme activities and metal contents of the variants were measured. Our studies indicated that His-150, His-200, His-231, His-233, and Asp-154 are essential for the enzyme activity of ΔN-term ALE-1. Except for His-150 and Asp-154, all of these amino acids were located within the 38-amino-acid region conserved among 11 proteins, including 5 staphylolytic endopeptidases. Inductively coupled plasma-mass spectrometric analysis of ΔN-term ALE-1 revealed that it contains one atom of zinc per molecule. Measurement of the zinc content of the mutant ΔN-term ALE-1 suggested that His-150 and -233 are important for zinc binding; their loss in these variant enzymes coincided with the loss of staphylolytic activity. These results strongly suggest that ALE-1 is a novel member of zinc metalloproteases.
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Zhu, Rongfeng, Yanqun Song, Haiping Liu, Yufei Yang, Shenlin Wang, Chengqi Yi, and Peng R. Chen. "Allosteric histidine switch for regulation of intracellular zinc(II) fluctuation." Proceedings of the National Academy of Sciences 114, no. 52 (December 11, 2017): 13661–66. http://dx.doi.org/10.1073/pnas.1708563115.
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Metalloregulators allosterically control transcriptional activity through metal binding-induced reorganization of ligand residues and/or hydrogen bonding networks, while the coordination atoms on the same ligand residues remain seldom changed. Here we show that the MarR-type zinc transcriptional regulator ZitR switches one of its histidine nitrogen atoms for zinc coordination during the allosteric control of DNA binding. The Zn(II)-coordination nitrogen on histidine 42 within ZitR’s high-affinity zinc site (site 1) switches from Nε2 to Nδ1 upon Zn(II) binding to its low-affinity zinc site (site 2), which facilitates ZitR’s conversion from the nonoptimal to the optimal DNA-binding conformation. This histidine switch-mediated cooperation between site 1 and site 2 enables ZitR to adjust its DNA-binding affinity in response to a broad range of zinc fluctuation, which may allow the fine tuning of transcriptional regulation.
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Zhang, Tuo, Eziz Kuliyev, Dexin Sui, and Jian Hu. "The histidine-rich loop in the extracellular domain of ZIP4 binds zinc and plays a role in zinc transport." Biochemical Journal 476, no. 12 (June 28, 2019): 1791–803. http://dx.doi.org/10.1042/bcj20190108.
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Abstract The Zrt-/Irt-like protein (ZIP) family mediates zinc influx from extracellular space or intracellular vesicles/organelles, playing a central role in systemic and cellular zinc homeostasis. Out of the 14 family members encoded in human genome, ZIP4 is exclusively responsible for zinc uptake from dietary food and dysfunctional mutations of ZIP4 cause a life-threatening genetic disorder, Acrodermatitis Enteropathica (AE). About half of the missense AE-causing mutations occur within the large N-terminal extracellular domain (ECD), and our previous study has shown that ZIP4–ECD is crucial for optimal zinc uptake but the underlying mechanism has not been clarified. In this work, we examined zinc binding to the isolated ZIP4–ECD from Pteropus Alecto (black fruit bat) and located zinc-binding sites with a low micromolar affinity within a histidine-rich loop ubiquitously present in ZIP4 proteins. Zinc binding to this protease-susceptible loop induces a small and highly localized structural perturbation. Mutagenesis and functional study on human ZIP4 by using an improved cell-based zinc uptake assay indicated that the histidine residues within this loop are not involved in preselection of metal substrate but play a role in promoting zinc transport. The possible function of the histidine-rich loop as a metal chaperone facilitating zinc binding to the transport site and/or a zinc sensor allosterically regulating the transport machinery was discussed. This work helps to establish the structure/function relationship of ZIP4 and also sheds light on other metal transporters and metalloproteins with clustered histidine residues.
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Davie, R. J., J. D. Phillips, and N. J. Birch. "The effect of zinc-histidine ratios on zinc intestinal absorption." Journal of Inorganic Biochemistry 43, no. 2-3 (August 1991): 686. http://dx.doi.org/10.1016/0162-0134(91)84653-q.
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Dyja, Renata, Barbara Dolińska, and Florian Ryszka. "Release of selected amino acids from zinc carriers." Acta Pharmaceutica 66, no. 2 (June 1, 2016): 269–77. http://dx.doi.org/10.1515/acph-2016-0024.
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Abstract The paper deals with the results of an investigation of the release of selected amino acids (histidine, tryptophan, tyrosine) from model suspensions prepared by co-precipitation with zinc chloride. It has been proven that the influence of the Zn(II)/amino acid molar ratio on dissolution profiles of the tested amino acids and dissolution half-life (t1/2) of histidine or tryptophan is significant. The amount of amino acid in the dispersed phase (supporting dose) is a determinant of the amino acid release profile. There is a minimal supporting dose (30.0 μmol of histidine or 17.4 μmol of tryptophan) that provides release of similar amounts of amino acid (4.1–4.6 μmol of histidine or 8.7–9.9 μmol of tryptophan) after the same time intervals. The tyrosine release profiles follow first order kinetics since the supporting dose (0.9–11.2 μmol) is limited by the tyrosine low solubility in water.
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Lee, Myungwoon, Tuo Wang, Olga V. Makhlynets, Yibing Wu, Nicholas F. Polizzi, Haifan Wu, Pallavi M. Gosavi, et al. "Zinc-binding structure of a catalytic amyloid from solid-state NMR." Proceedings of the National Academy of Sciences 114, no. 24 (May 31, 2017): 6191–96. http://dx.doi.org/10.1073/pnas.1706179114.
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Throughout biology, amyloids are key structures in both functional proteins and the end product of pathologic protein misfolding. Amyloids might also represent an early precursor in the evolution of life because of their small molecular size and their ability to self-purify and catalyze chemical reactions. They also provide attractive backbones for advanced materials. When β-strands of an amyloid are arranged parallel and in register, side chains from the same position of each chain align, facilitating metal chelation when the residues are good ligands such as histidine. High-resolution structures of metalloamyloids are needed to understand the molecular bases of metal–amyloid interactions. Here we combine solid-state NMR and structural bioinformatics to determine the structure of a zinc-bound metalloamyloid that catalyzes ester hydrolysis. The peptide forms amphiphilic parallel β-sheets that assemble into stacked bilayers with alternating hydrophobic and polar interfaces. The hydrophobic interface is stabilized by apolar side chains from adjacent sheets, whereas the hydrated polar interface houses the Zn2+-binding histidines with binding geometries unusual in proteins. Each Zn2+ has two bis-coordinated histidine ligands, which bridge adjacent strands to form an infinite metal–ligand chain along the fibril axis. A third histidine completes the protein ligand environment, leaving a free site on the Zn2+ for water activation. This structure defines a class of materials, which we call metal–peptide frameworks. The structure reveals a delicate interplay through which metal ions stabilize the amyloid structure, which in turn shapes the ligand geometry and catalytic reactivity of Zn2+.
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Erk, Inge, Jean-Claude Huet, Mariela Duarte, Stéphane Duquerroy, Felix Rey, Jean Cohen, and Jean Lepault. "A Zinc Ion Controls Assembly and Stability of the Major Capsid Protein of Rotavirus." Journal of Virology 77, no. 6 (March 15, 2003): 3595–601. http://dx.doi.org/10.1128/jvi.77.6.3595-3601.2003.
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ABSTRACT The recent determination of the crystal structure of VP6, the major capsid protein of rotavirus, revealed a trimer containing a central zinc ion coordinated by histidine 153 from each of the three subunits. The role of the zinc ion in the functions of VP6 was investigated by site-directed mutagenesis. The mutation of histidine 153 into a serine (H153S and H153S/S339H) did not prevent the formation of VP6 trimers. At pH <7.0, about the pK of histidine, wild-type and mutated VP6 proteins display similar properties, giving rise to identical tubular and spherical assemblies. However, at pH >7.0, histidine 153 mutant proteins did not assemble into the characteristic 45-nm-diameter tubes, in contrast to wild-type VP6. These observations showed that under conditions in which histidine residues are not charged, the properties of VP6 depended on the presence of the centrally coordinated zinc atom in the trimer. Indeed, wild-type VP6 depleted of the zinc ion by a high concentration (100 mM) of a metal-chelating agent behaved like the H153 mutant proteins. The susceptibility of wild-type VP6 to proteases is greatly increased in the absence of zinc. NH2-terminal sequencing of the proteolytic fragments showed that they all contained the β-sheet-rich VP6 head domain, which appeared to be less sensitive to protease activity than the α-helical basal domain. Finally, the mutant proteins assembled well on cores, as demonstrated by both electron microscopy and rescue of transcriptase activity. Zinc is thus not necessary for the transcription activity. All of these observations suggest that, in solution, VP6 trimers present a structural flexibility that is controlled by the presence of a zinc ion.
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Glover, Chris N., and Christer Hogstrand. "Amino acid modulation of in vivo intestinal zinc absorption in freshwater rainbow trout." Journal of Experimental Biology 205, no. 1 (January 1, 2002): 151–58. http://dx.doi.org/10.1242/jeb.205.1.151.
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SUMMARY The composition of the intestinal lumen is likely to have considerable influence upon the absorption, and consequently the nutrition and/or toxicity, of ingested zinc in aquatic environments, where zinc is both a nutrient and a toxicant of importance. The effects of amino acids upon intestinal zinc uptake in freshwater rainbow trout (Oncorhynchus mykiss) were studied using an in vivo perfusion technique. The presence of histidine, cysteine and taurine had distinct modifying actions upon quantitative and qualitative zinc absorption, compared to perfusion of zinc alone. Alterations in zinc transport were not correlated with changes in levels of free zinc ion. The chemical nature of the zinc–amino acid chelate, rather than the chelation itself, appeared to have the most important influence upon zinc absorption. l-histidine, despite a strong zinc-chelating effect, maintained quantitative zinc uptake at control (zinc alone) levels. This effect correlated with the formation of Zn(His)2 species. d-histidine at a luminal concentration of 100 mmol l–1 significantly enhanced subepithelial zinc accumulation, but reduced the fraction of zinc that was retained and absorbed by the fish. The possibility of a Zn(His)2-mediated pathway for intestinal uptake is discussed. l-cysteine specifically stimulated the accumulation of zinc post-intestinally, an effect attributed to enhanced zinc accumulation in the blood. Taurine increased subepithelial zinc accumulation, but decreased the passage of zinc to post-intestinal compartments. Amino acids are proposed to have important roles in modifying intestinal zinc uptake with potential implications for environmental toxicity as well as aquaculture.
Dissertations / Theses on the topic "Zinc Histidine"
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Hanissian, Silvia H. "Modulation of brain opioid receptors by zinc and histidine /." The Ohio State University, 1988. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487596807821341.
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Oakley, Fiona. "Histidine stimulated trace element uptake into human erythrocytes, HEL cells and HEL total RNA injected Xenopus laevis oocytes." Thesis, University of Southampton, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340362.
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Soebbing, Samantha Lynn. "Incorporation of histidine-rich metal-binding sites onto small protein scaffolds implications for imaging, therapeutics, and catalysis /." Diss., University of Iowa, 2008. http://ir.uiowa.edu/etd/37.
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Forry, Erin Patricia. "The Effect of Zinc on the Transmural Transport of L-H-Histidine in the Intestinal Epithelium of the American Lobster, Homarus Americanus." Thesis, University of Hawaii at Manoa, 2002. http://hdl.handle.net/10125/6947.
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Alpdogan, Serdar [Verfasser], Wolfgang [Gutachter] Walkowiak, and Heike [Gutachter] Endepols. "Intracerebroventrikuläre Injektionen von Zink Ionen und Histidin als Carrier modulieren die Anfallsaktivität nach experimentell induzierter Epileptogenese unterschiedlich in Cav2.3-defizienten Mäusen und Kontrolltieren / Serdar Alpdogan ; Gutachter: Wolfgang Walkowiak, Heike Endepols." Köln : Universitäts- und Stadtbibliothek Köln, 2020. http://d-nb.info/1215293852/34.
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Chen, Tzu-Yin, and 陳子胤. "Zinc(II)-induced self-assembly of poly-histidine-fused protein and POG peptide for protein drug controlled release." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/mnvs7m.
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碩士國立交通大學
應用化學系分子科學碩博士班
103
In recent years, protein microparticles have received much attention in the drug delivery systems due to the improved protein stability and prolonged release in vivo. However, most of current preparation processes involved harsh conditions, introducing chemical crosslinkers or high salt, which often led to protein inactivation and failed to apply in drug delivery systems. In this study, we employed the well-established hexahistidine (His)-tag recombinant protein technology as well as a metal-triggerable peptide to enhance the binding strength between protein and metal ion and to fine-tune the protein drug release. The His-tagged proteins could self-assemble to form microparticles (~ 2 μm) upon zinc chloride (1 mM) treatment and an eight-hour sustained protein drug release has been achieved in physiological saline. The experimental results also indicated that by adjusting the peptide concentration and the N- and C-terminal hexahistidine-tags, the protein release could be controlled. Moreover, no protein denaturation has been observed. We have developed a universal strategy to enable facile protein microparticles fabrication under mild conditions, and their potential in release-tunable protein drug delivery systems has been successfully demonstrated.
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柯思妤. "Self-Assembly, Structural Diversity and Properties of L-histidine-containing Chiral Zinc(II), Nickel(II) and Cadmium(II) Metal Compounds." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/93353191176790163831.
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碩士國立臺灣師範大學
化學系
101
The goal of this study was to develop a self-assembly synthetic strategy for the preparation of metal–organic coordination polymers using L-2-amino-3-(1H-imidazol-4-yl)propanic acid (L-histidine), 4,4’-bipyridine (bipy) and 5,5’-bipyrimidine (bpym) in combination with different transition metal ions. The solid state structures of the products were characterized by FT-IR spectroscopy, elemental analysis, thermogravimetric analysis and single-crystal X-ray diffraction methodology. The reaction of L-histidine with Zn(II) or Ni(II) ions leads to the formation of neutral monomeric compounds, [M(L-his)2]H2O (M = Zn (1), Ni (2)). In 1, the Zn(II) centers are coordinated by two N atoms of two different imidazoles and two N atoms of the NH2 groups of two L-histidine ligands to form a tetrahedral geometry. In 2, the nickel(II) centers are coordinated to two L-histidine ligands in a tridentate fashion through N, NH2 and O to furnish an octahedral geometry. In another reaction, when Cd(II) ion is allowed to react with 4,4’-bipyridine and L-histidine, in the present of perchlorate (ClO4 ) or nitrate (NO3 ), the coordination polymers {[Cd(bipy)(L-his)(H2O)](ClO4)}n (3), {[Cd(bipy)(L-his)(H2O)](NO3)H2O}n (4), respectively, are formed. The molecular structures of 3 and 4 reveal that the L-histidine acts as a bridging ligand, adopting a bis-chelating coordination mode through the N atom of the NH2 group and four O atoms of carboxylates to form a 1-D chain. The 4,4’-bipyridine ligands are then connected with each chain to afford a 2-D layered structure. In these series, the de-/ad-sorption behavior of coordinated water molecules and guest water molecules are supported by TGA technology. The results show that the process is reversible when the system is exposed to water vapor. In particular, the chemical and physical adsorption behavior of 4 can be clearly differentiated from the TGA patterns. When Cd(NO3)2 or Cd(ClO4)2 is reacted with 5,5’-bipyrimidine and L-histidine, the coordination polymers {[Cd(bpym)0.5(L-his)(H2O)](NO3)C2H5OH}n (5) and {[Cd(bpym)0.5(L-his)(H2O)](ClO4)H2O}n (6), respectively, are formed. In 5 and 6, the Cd(II) centers are coordinated with L-histidine ligands in a tetradentate coordination mode via the N atom of imidazole, the N atom of an NH2 group and two carboxylate O atoms to form a 1-D chain. In addition, 5,5’-bipyrimidine is connected to each chain of 5 and 6 via cis- and trans form, respectively, to form a 2-D layer and a 3-D structure. Key word：chiral, L-histidine, metal-organic framework, self-assembly.
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Licuco, Ana Cristina Julião. "Biochemical approach to study the spider fang." Master's thesis, 2013. http://hdl.handle.net/10316/24657.
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Dissertação de mestrado em Bioquímica, apresentada ao Departamento Ciências da Vida da Faculdade de Ciências e Tecnologia da Universidade de CoimbraThe environmental context where some animal are found may often explain some of their characteristics. This is not different for arthropods whose body is covered by an exoskeleton, the cuticle, a structure that, among other functions, confreres protection, shape and defense against parasite invasion. This is possible thanks to the organization of the exoskeleton in different layers with very specific characteristics. The cuticle of arthropods, composed of chitin and protein, exhibits notable variations in both organization and local microstructure. This situation occurs for all body anatomical structures containing cuticle and with different patterns of microstructural and chemical gradients between them. This work aims to give information about the organization of the cuticle of arthropods, using the spider Cupiennius salei as a model, and focusing the attention on the protein content. The project was developed assuming the existence of so far unidentified metal-dependent proteins, where the metal coordination is possible due to the presence of histidines, situation that also contributes to the mechanical properties of the cuticle. The project comprises the establishment of a principle for extraction, purification based on zinc affinity and characterization of proteins from cuticles of abdomen, tibia and fangs of Cupiennius salei. The optimization of the protein extraction and purification will allow the characterization of these proteins and the possible establishment of homology with proteins, of other organisms, with similar amino acid compositions and sequences and/or common functions.
O contexto ambiental em que alguns animais são encontrados pode muitas vezes explicar algumas das suas características. Tal não é diferente para os artrópodes cujo corpo é coberto por um exosqueleto, a cutícula, uma estrutura que, para além de outras funcões, confere protecção, forma e defesa contra invação de parasitas. isto é possível graças à organização do exosqueleto em diferentes camadas com características bastante específicas. A cutícula dos artrópodes, composta de quitina e proteínas, exibe oscilações notáveis quer a nível de organização quer a nível de micro-estrutura local. Esta situação occore em todas as estruturas anatómicas do corpo que contêm cutícula e com diferentes padrões micro-estruturais e gradientes químicos entre elas. Este trabalho tem por objectivo facultar mais informação acerca da cutícula de artrópodes, usando como modelo a aranha Cupiennius salei, e focando atenções no conteúdo proteico. O projecto foi desenvolvido assumindo a existência de proteínas metalo-dependentes, até agora não identificadas, onde a coordenação metálica é possível devido à existência de histidinas, situação que contribui igualmente para as propriedades mecânicas da cutícula. O projecto compreendede o estabelecimento de uma metodologia para a extraccção, purificação tendo por base a afinidade por zinco e caracterização de proteínas da cutícula de abdomen, tíbia e presas de Cupiennius salei,. A optimização do processo de extracção e purificação permitirão a caracterização dessas proteínas e o possível estabelecimento de homologias com proteínas, existentes noutros organismos, com composições de aminoácidos e sequências semelhantes e/ou funções comuns.
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Moreira, Marilia Outerelo João. "O papel do cobre nas doenças de Wilson e de Menkes : Estratégias terapêuticas." Master's thesis, 2014. http://hdl.handle.net/10451/26861.
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Trabalho Final de Mestrado Integrado, Ciências Farmacêuticas, Universidade de Lisboa, Faculdade de Farmácia, 2014O cobre é um oligoelemento essencial, interveniente em diversas funções fisiológicas, na medida em que existem uma série de mecanismos homeostáticos que permitem que actue como cofactor em processos enzimáticos e evitam a sua acumulação em níveis tóxicos. Na presente monografia, procede-se à revisão bibliográfica das alterações genéticas que envolvem o metabolismo deste metal, nomeadamente no que respeita às Doenças de Wilson e de Menkes, cujos genes responsáveis pelo seu desenvolvimento são, respectivamente, designados por ATP7B e ATP7A. Ambas as proteínas por eles codificadas são responsáveis pelo transporte de cobre a partir do citoplasma para o complexo de Golgi, apesar das patologias serem diferentes: a Doença de Wilson encontra-se relacionada com a acumulação de cobre no organismo, enquanto a Doença de Menkes está associada a uma deficiência nos níveis deste metal. Este facto, pode ser explicado pelo tipo de células em que as referidas proteínas se encontram presentes, sendo que a proteína ATP7A é expressa em todos os tipos celulares, à excepção dos hepatócitos, enquanto a proteína ATP7B é maioritariamente expressa no tecido hepático. A Doença de Wilson é, então, uma doença autossómica recessiva que afecta principalmente o sistema nervoso e hepático dos indivíduos. Actualmente, o tratamento consiste na administração de agentes quelantes (D-Penicilamina, Trietilenotetramina e Tetratiomolibdato) e/ou sais de zinco. Por outro lado, a Doença de Menkes, associada ao cromossoma X, tem como manifestações típicas as alterações neurológicas, no tecido conjuntivo e a nível capilar, consistindo o tratamento na administração parentérica do complexo cobre-histidina.
Book chapters on the topic "Zinc Histidine"
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Afolabi, Olakunle Bamikole, Bose Damilola Balogun, Omotade Ibidun Oloyede, and Ayodele Jacob Akinyemi. "Zinc and Neurodegenerative Disorders." In Advances in Medical Diagnosis, Treatment, and Care, 176–93. IGI Global, 2019. http://dx.doi.org/10.4018/978-1-5225-5282-6.ch008.
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Zinc (Zn) is an essential trace element that is abundantly present in humans. Despite its importance in normal brain functions, alterations in zinc homeostasis cause various neurological pathologies such as dementia, Parkinson's disease, Prion's disease, etc. A growing body of evidence has shown that zinc might play a dual role: in which both zinc depletion and excess zinc cause severe damage and hence neurotoxicity develops. Homeostatic controls are put in place to avoid the accumulation of excess zinc or its deficiency. This cellular zinc homeostasis results from the actions of a coordinated regulation effected by different proteins involved in the uptake, excretion, and intracellular storage or trafficking of zinc. Further investigation has also shown the role of endogenous carnosine (beta-alanyl-L-histidine) in binding excess zinc. Hence, it has the ability to prevent neurotoxicity. Also, the role of a zinc-rich diet cannot be overemphasized. The authors of the chapter, however, provide an insight into the link between zinc homeostasis and neurodegenerative disorders (NDs).
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Schilsky, Michael L., and Pramod K. Mistry. "Inherited diseases of copper metabolism: Wilson’s disease and Menkes’ disease." In Oxford Textbook of Medicine, edited by Timothy M. Cox, 2115–20. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0234.
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Copper is an essential metal that is an important cofactor for many proteins and enzymes. Two related genetic defects in copper transport have been described, each with distinct phenotypes. Wilson’s disease—an uncommon disorder (1 in 30 000) caused by autosomal recessive loss-of-function mutations in a metal-transporting P-type ATPase (ATP7B) that result in defective copper excretion into bile and hence copper toxicity. Typical presentation is in the second and third decade of life with liver disease (ranging from asymptomatic to acute fulminant hepatic failure or chronic end-stage liver disease) or neurological or psychiatric disorder (dystonia, dysarthria, parkinsonian tremor, movement disorder, a spectrum of psychiatric ailments). While no single biochemical test or clinical finding is sufficient for establishing the diagnosis, typical findings include low serum ceruloplasmin, high urinary copper excretion, and elevated liver copper content. Corneal Kayser–Fleischer rings may be seen. Treatment is with copper chelating agents and zinc. Liver transplantation is required for fulminant hepatic failure and decompensated liver disease unresponsive to medical therapy. Menkes’ disease—a rare disorder (1 in 300 000) caused by X-linked loss-of-function mutations in a P-type ATPase homologous to ATP7B (ATP7A) that result in defective copper transport across intestine, placenta, and brain and hence cellular copper deficiency. Clinical presentation is in infancy with facial dimorphism, connective tissue disorder, hypopigmentation, abnormal hair, seizures, and failure to thrive, usually followed by death by age 3 years (although some variants with a milder phenotype result from milder mutations, e.g. occipital horn syndrome). Treatment, which is only effective when presymptomatic diagnosis is made in a sibling after florid presentation in a previous affected sibling, is with intravenous copper histidine.