1
|
Inan-Eroglu E, Ayaz A. Is aluminum exposure a risk factor for neurological disorders? JOURNAL OF RESEARCH IN MEDICAL SCIENCES : THE OFFICIAL JOURNAL OF ISFAHAN UNIVERSITY OF MEDICAL SCIENCES 2018; 23:51. [PMID: 30057635 PMCID: PMC6040147 DOI: 10.4103/jrms.jrms_921_17] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 02/06/2018] [Accepted: 03/05/2018] [Indexed: 02/05/2023]
Abstract
Aluminum (Al) is widely found in the nature. Although the relation between Al and neurodegenerative diseases is still controversial, Al is related with many brain diseases including Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Al exposure occurs mainly through environment, occupational, and dietary factors for humans. Al exposure with diet can be through foods, food additives, water, and contamination of Al equipment/utensils. The aim of this review is to summarize various hypotheses, which link Al and neurodegeneration, and to determine the roles of Al exposure through different sources including diet, environment, and occupation. Future studies should be done in vulnerable subgroups of population including children, patients receiving antacid or Al-containing pharmeteucials on a daily basis, patients with reduced renal function, and patients on parenteral nutrition regimens that are likely to be affected by possible adverse health effects of Al. In addition, gender, age, and Al interactions need to be determined. One of the most important challanges in future epidemiological studies is to determine which variables should be controlled. In addition, experimental studies should be more focused and translational. In this context, exposure dose, dose-response effects, and time lapse between exposures and cognitive assessments are very important.
Collapse
Affiliation(s)
- Elif Inan-Eroglu
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, Ankara, Turkey
| | - Aylin Ayaz
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, Ankara, Turkey
| |
Collapse
|
2
|
Mujika JI, Dalla Torre G, Formoso E, Grande-Aztatzi R, Grabowski SJ, Exley C, Lopez X. Aluminum's preferential binding site in proteins: sidechain of amino acids versus backbone interactions. J Inorg Biochem 2017; 181:111-116. [PMID: 29183625 DOI: 10.1016/j.jinorgbio.2017.10.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/14/2017] [Accepted: 10/30/2017] [Indexed: 10/18/2022]
Affiliation(s)
- Jon I Mujika
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain
| | - Gabriele Dalla Torre
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain
| | - Elena Formoso
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain
| | - Rafael Grande-Aztatzi
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain
| | - Slawomir J Grabowski
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain; IKERBASQUE, Basque Foundation for Science, 48011 Bilbao, Spain
| | - Christopher Exley
- Birchall Centre, Lennard-Jones Laboratories, Keele University, Staffordshire ST5 5BG, UK
| | - Xabier Lopez
- Kimika Fakultatea, Euskal Herriko Unibertsitatea UPV/EHU, Donostia International Physics Center (DIPC), P.K. 1072, 20080 Donostia, Euskadi, Spain.
| |
Collapse
|
3
|
Mensonides FIC, Bakker BM, Cremazy F, Messiha HL, Mendes P, Boogerd FC, Westerhoff HV. A new regulatory principle for in vivo biochemistry: pleiotropic low affinity regulation by the adenine nucleotides--illustrated for the glycolytic enzymes of Saccharomyces cerevisiae. FEBS Lett 2013; 587:2860-7. [PMID: 23856461 DOI: 10.1016/j.febslet.2013.07.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 07/03/2013] [Indexed: 10/26/2022]
Abstract
Enzymology tends to focus on highly specific effects of substrates, allosteric modifiers, and products occurring at low concentrations, because these are most informative about the enzyme's catalytic mechanism. We hypothesized that at relatively high in vivo concentrations, important molecular monitors of the state of living cells, such as ATP, affect multiple enzymes of the former and that these interactions have gone unnoticed in enzymology. We test this hypothesis in terms of the effect that ATP, ADP, and AMP might have on the major free-energy delivering pathway of the yeast Saccharomyces cerevisiae. Assaying cell-free extracts, we collected a comprehensive set of quantitative kinetic data concerning the enzymes of the glycolytic and the ethanol fermentation pathways. We determined systematically the extent to which the enzyme activities depend on the concentrations of the adenine nucleotides. We found that the effects of the adenine nucleotides on enzymes catalysing reactions in which they are not directly involved as substrate or product, are substantial. This includes effects on the Michaelis-Menten constants, adding new perspective on these, 100 years after their introduction.
Collapse
Affiliation(s)
- Femke I C Mensonides
- Department of Molecular Cell Physiology, Faculty of Earth and Life Sciences, VU University Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
4
|
Kawahara M, Kato-Negishi M. Link between Aluminum and the Pathogenesis of Alzheimer's Disease: The Integration of the Aluminum and Amyloid Cascade Hypotheses. Int J Alzheimers Dis 2011; 2011:276393. [PMID: 21423554 PMCID: PMC3056430 DOI: 10.4061/2011/276393] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Revised: 11/29/2010] [Accepted: 01/05/2011] [Indexed: 12/21/2022] Open
Abstract
Whilst being environmentally abundant, aluminum is not essential for life. On the contrary, aluminum is a widely recognized neurotoxin that inhibits more than 200 biologically important functions and causes various adverse effects in plants, animals, and humans. The relationship between aluminum exposure and neurodegenerative diseases, including dialysis encephalopathy, amyotrophic lateral sclerosis and Parkinsonism dementia in the Kii Peninsula and Guam, and Alzheimer's disease (AD) has been suggested. In particular, the link between aluminum and Alzheimer's disease has been the subject of scientific debate for several decades. However, the complex characteristics of aluminum bioavailability make it difficult to evaluate its toxicity and therefore, the relationship remains to be established. Mounting evidence has suggested that significance of oligomerization of β-amyloid protein and neurotoxicity in the molecular mechanism of AD pathogenesis. Aluminum may play crucial roles as a cross-linker in β-amyloid oligomerization. Here, we review the detailed characteristics of aluminum neurotoxicity based on our own studies and the recent literatures. Our aim is to revisit the link between aluminum and AD and to integrate aluminum and amyloid cascade hypotheses in the context of β-amyloid oligomerization and the interactions with other metals.
Collapse
Affiliation(s)
- Masahiro Kawahara
- Department of Analytical Chemistry, School of Pharmaceutical Sciences, Kyushu University of Health and Welfare, 1714-1 Yoshino-cho, Nobeoka-shi, Miyazaki 882-8508, Japan
| | | |
Collapse
|
5
|
Wang T, Kang J. Hexokinase inhibitor screening based on adenosine 5'-diphosphate determination by electrophoretically mediated microanalysis. Electrophoresis 2009; 30:1349-54. [PMID: 19306267 DOI: 10.1002/elps.200800542] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A CE-based method for hexokinase inhibitor screening was developed in the present paper. In this method, hexokinase activity was assayed via electrophoretically mediated microanalysis (EMMA), which combines on-column hexokinase-mediated reaction and measurement of produced adenosine 5'-diphosphate (ADP) via electrophoretical separation and UV detection. Enzyme inhibition can be read out directly from the reduced peak area of ADP in comparison with a reference electropherogram obtained in the absence of any inhibitor. Conditions for on-column enzyme reaction and separation of adenosine 5'-triphosphate (ATP) and ADP were optimized. The optimal buffer composition for enzymatic reaction was 25 mM HEPES buffer (pH 7.5) containing 5 mM MgCl(2), whereas the optimal buffer composition for separation was 100 mM Tris-phosphate buffer (pH 5.5) containing 0.02% (m/v) hexadimethrine bromide (HDB). Fortunately, discontinuous buffer system can be adapted easily in the EMMA method. The time for separation was reduced dramatically to less than 3 min by reversing the direction of EOF via dynamically coating the capillary wall with the cationic polyelectrolyte HDB. Moreover, the peak tailing of ATP was also reduced by HDB coating. The Z' factor as high as 0.98 was obtained, indicating a high quality of the screening data. The present method is simple, robust and cost-effective.
Collapse
Affiliation(s)
- Tongdan Wang
- Shanghai Institute of Organic Chemistry, Chinese Academy of Science, Shanghai, PR China
| | | |
Collapse
|
6
|
Romero CS, Olmo R, Teijón C, Blanco MD, Teijón JM, Romero A. Structural and functional implications of the hexokinase-nickel interaction. J Inorg Biochem 2005; 99:2395-402. [PMID: 16256202 DOI: 10.1016/j.jinorgbio.2005.09.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2005] [Revised: 09/12/2005] [Accepted: 09/16/2005] [Indexed: 11/27/2022]
Abstract
The interaction between nickel and yeast hexokinase was studied. The binding of nickel showed a positive cooperativity, and saturation was not reached. The nickel binding induced modifications in the secondary structure of the protein; thus, a lost of alpha helix and beta turns, as well as an increase of the random structure and beta sheet was observed. The monomer/dimmer equilibrium of the protein was modified in the presence of nickel, and the monomer state was mainly obtained at the highest nickel concentrations studied. These changes on the protein structure caused a decrease in the enzyme activity. According to kinetic studies, nickel caused a non-competitive inhibition when glucose was the variable substrate and a linear competitive inhibition when ATP was the variable substrate.
Collapse
Affiliation(s)
- C S Romero
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | | | | | | | | | | |
Collapse
|
7
|
Gao H, Leary JA. Multiplex inhibitor screening and kinetic constant determinations for yeast hexokinase using mass spectrometry based assays. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2003; 14:173-81. [PMID: 12648923 DOI: 10.1016/s1044-0305(02)00867-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
An electrospray ionization mass spectrometry based assay was developed for kinetic measurements and inhibitor screening of yeast hexokinase. There is considerable discrepancy in the literature as to the accuracy of kinetic data obtained for hexokinase. In the assay described herein, the product, glucose 6-phosphate was directly monitored by ion trap mass spectrometry and quantified using an internal standard, 2 deoxy-glucose 6-phosphate. The kinetic parameters, K(M) and V(max) for the two substrates were determined without using a coupling enzyme as is normally employed in the traditional spectrophotometric assay for systems lacking a chromophore. In addition, hexokinase was successfully immobilized onto an amino-link gel, and a mock library was screened against the immobilized enzyme for the identification of possible inhibitors. After comparing the mass spectra of the library before and after incubation, trehalose 6-phosphate, ADP, and oxidized glutathione were differentiated from other weak or non-inhibitors. Inhibition behavior of ADP with respect to ATP was further evaluated with the ESI-MS assay and the value of K(i) was determined. This ESI-MS assay was demonstrated to be both accurate and precise for determining kinetic constants and for identifying enzyme inhibitors.
Collapse
Affiliation(s)
- Hong Gao
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720-1460, USA
| | | |
Collapse
|
8
|
Olmo R, Blanco MD, Teijón C, Miguel del Socorro J, Teijón JM. Studies of cadmium binding to hexokinase: structural and functional implications. J Inorg Biochem 2002; 89:107-14. [PMID: 11931970 DOI: 10.1016/s0162-0134(01)00367-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The interaction between cadmium and yeast hexokinase was studied. Cadmium produces changes in the aggregation state of the protein and large structures with a large molecular mass were formed. This phenomenon occurs without large modifications to the secondary structure. During this change the enzyme maintains a high level of activity in the monomer as well as in aggregate form. This implies that the enzyme function is not greatly affected by the change and it maintains its active sites without significant modifications. According to kinetic measurements with both glucose and ATP as a variable substrate, cadmium causes a mixed-type inhibition with a main uncompetitive component. Binding experiments show that the protein presents negative cooperative binding with cadmium at various temperatures (298, 303 and 313 K) and a progressive loss in metal union with concentration depending on the temperature. The total union percentage decreases as the metal concentration increases. This is probably due to the aggregation process, which affects the binding sites for the metal and also for the substrate. Labile interactions are more persistent than specific interactions in accordance with the solvation parameter.
Collapse
Affiliation(s)
- Rosa Olmo
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Universidad Complutense de Madrid, 28040, Madrid, Spain
| | | | | | | | | |
Collapse
|