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Voziyan P, Brown KL, Uppuganti S, Leser M, Rose KL, Nyman JS. A map of glycation and glycoxidation sites in collagen I of human cortical bone: Effects of sex and type 2 diabetes. Bone 2024; 187:117209. [PMID: 39047900 DOI: 10.1016/j.bone.2024.117209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/19/2024] [Accepted: 07/21/2024] [Indexed: 07/27/2024]
Abstract
Complications of diabetes is a major health problem affecting multiple organs including bone, where the chronic disease increases the risk of fragility fractures. One hypothesis suggests a pathogenic role for hyperglycemia-induced modification of proteins, a.k.a. advanced glycation end products (AGEs), resulting in structural and functional damage to bone extracellular matrix (ECM). Evidence supporting this hypothesis has been limited by the lack of comprehensive information about the location of AGEs that accumulate in vivo at specific sites within the proteins of bone ECM. Analyzing extracts from cortical bone of cadaveric femurs by liquid chromatography tandem mass spectrometry, we generated a quantitative AGE map of human collagen I for male and female adult donors with and without diabetes. The map describes the chemical nature, sequence position, and levels of four major physiological AGEs, e.g. carboxymethyllysine, and an AGE precursor fructosyllysine within the collagen I triple-helical region. The important features of the map are: 1) high map reproducibility in the individual bone extracts, i.e. 20 male and 20 female donors; 2) localization of modifications to distinct clusters: 10 clusters containing 34 AGE sites in male donors and 9 clusters containing 28 sites in female donors; 3) significant increases in modification levels in diabetes at multiple sites: 26 out of 34 sites in males and in 17 out of 28 sites in females; and 4) generally higher modification levels in male vs. female donors. Moreover, the AGE levels at multiple individual sites correlated with total bone pentosidine levels in male but not in female donors. Molecular dynamics simulations and molecular modeling predicted significant impact of modifications on solvent exposure, charge distribution, and hydrophobicity of the triple helix as well as disruptions to the structure of collagen I fibril. In summary, the AGE map of collagen I revealed diabetes-induced, sex-specific non-enzymatic modifications at distinct triple helical sites that can disrupt collagen structure, thus proposing a specific mechanism of AGE contribution to diabetic complications in human bone.
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Affiliation(s)
- Paul Voziyan
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212, USA.
| | - Kyle L Brown
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212, USA; Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN 37212, USA; Center for Structural Biology, Vanderbilt University, Nashville, TN 37240, USA
| | - Sasidhar Uppuganti
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Micheal Leser
- Department of Biochemistry and Proteomics Core, Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232, USA
| | - Kristie Lindsey Rose
- Department of Biochemistry and Proteomics Core, Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232, USA
| | - Jeffry S Nyman
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212, USA; Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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2
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Voziyan P, Uppuganti S, Leser M, Rose KL, Nyman JS. Mapping glycation and glycoxidation sites in collagen I of human cortical bone. BBA ADVANCES 2023; 3:100079. [PMID: 37082268 PMCID: PMC10074956 DOI: 10.1016/j.bbadva.2023.100079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 01/23/2023] Open
Abstract
Accumulation of advanced glycation end products (AGEs), particularly in long-lived extracellular matrix proteins, has been implicated in pathogenesis of diabetic complications and in aging. Knowledge about specific locations of AGEs and their precursors within protein primary structure is critical for understanding their physiological and pathophysiological impact. However, the information on specific AGE sites is lacking. Here, we identified sequence positions of four major AGEs, carboxymethyllysine, carboxyethyllysine, 5-hydro-5-methyl imidazolone, and 5-hydro-imidazolone, and an AGE precursor fructosyllysine within the triple helical region of collagen I from cortical bone of human femurs. The presented map provides a basis for site-specific quantitation of AGEs and other non-enzymatic post-translational modifications and identification of those sites affected by aging, diabetes, and other diseases such as osteoporosis; it can also help in guiding future studies of AGE impact on structure and function of collagen I in bone.
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Affiliation(s)
- Paul Voziyan
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, United States
- Vanderbilt Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, TN 37212, United States
| | - Sasidhar Uppuganti
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, United States
| | - Micheal Leser
- Department of Biochemistry and Proteomics Core, Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232, United States
| | - Kristie L. Rose
- Department of Biochemistry and Proteomics Core, Mass Spectrometry Research Center, Vanderbilt University, Nashville, TN 37232, United States
| | - Jeffry S. Nyman
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, United States
- Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN 37212, United States
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3
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Willett TL, Voziyan P, Nyman JS. Causative or associative: A critical review of the role of advanced glycation end-products in bone fragility. Bone 2022; 163:116485. [PMID: 35798196 PMCID: PMC10062699 DOI: 10.1016/j.bone.2022.116485] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 06/27/2022] [Accepted: 06/29/2022] [Indexed: 11/02/2022]
Abstract
The accumulation of advanced glycation end-products (AGEs) in the organic matrix of bone with aging and chronic disease such as diabetes is thought to increase fracture risk independently of bone mass. However, to date, there has not been a clinical trial to determine whether inhibiting the accumulation of AGEs is effective in preventing low-energy, fragility fractures. Moreover, unlike with cardiovascular or kidney disease, there are also no pre-clinical studies demonstrating that AGE inhibitors or breakers can prevent the age- or diabetes-related decrease in the ability of bone to resist fracture. In this review, we critically examine the case for a long-standing hypothesis that AGE accumulation in bone tissue degrades the toughening mechanisms by which bone resists fracture. Prior research into the role of AGEs in bone has primarily measured pentosidine, an AGE crosslink, or bulk fluorescence of hydrolysates of bone. While significant correlations exist between these measurements and mechanical properties of bone, multiple AGEs are both non-fluorescent and non-crosslinking. Since clinical studies are equivocal on whether circulating pentosidine is an indicator of elevated fracture risk, there needs to be a more complete understanding of the different types of AGEs including non-crosslinking adducts and multiple non-enzymatic crosslinks in bone extracellular matrix and their specific contributions to hindering fracture resistance (biophysical and biological). By doing so, effective strategies to target AGE accumulation in bone with minimal side effects could be investigated in pre-clinical and clinical studies that aim to prevent fragility fractures in conditions that bone mass is not the underlying culprit.
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Affiliation(s)
- Thomas L Willett
- Biomedical Engineering Program, Systems Design Engineering, University of Waterloo, Waterloo, Ontario, Canada.
| | - Paul Voziyan
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA
| | - Jeffry S Nyman
- Department of Orthopaedic Surgery, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Veterans Affairs, Tennessee Valley Healthcare System, Nashville, TN 37212, USA.
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4
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Lamprea-Montealegre JA, Arnold AM, McCLelland RL, Mukamal KJ, Djousse L, Biggs ML, Siscovick DS, Tracy RP, Beisswenger PJ, Psaty BM, Ix JH, Kizer JR. Plasma Levels of Advanced Glycation Endproducts and Risk of Cardiovascular Events: Findings From 2 Prospective Cohorts. J Am Heart Assoc 2022; 11:e024012. [PMID: 35904195 PMCID: PMC9375486 DOI: 10.1161/jaha.121.024012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Advanced glycation endproducts (AGEs) have been linked to cardiovascular disease (CVD) in cohorts with and without diabetes. Data are lacking on prospective associations of various α-dicarbonyl-derived AGEs and incident CVD in the general population. We tested the hypothesis that major plasma AGEs are associated with new-onset CVD in 2 population-based cohorts of differing age and comorbidities. Methods and Results Analyses involved a random subcohort (n=466) from the Cardiovascular Health Study and a case-cohort sample (n=1631) from the Multi-Ethnic Study of Atherosclerosis. Five AGEs and 2 oxidative products were measured by liquid chromatography tandem mass spectrometry. Associations with CVD (myocardial infarction and stroke) were evaluated with Cox regression. Participants in the Cardiovascular Health Study were older than the Multi-Ethnic Study of Atherosclerosis, and had more comorbidities, along with higher levels of all AGEs. During median follow-up of 11 years, 439 participants in the Multi-Ethnic Study of Atherosclerosis and 200 in the Cardiovascular Health Study developed CVD. After multivariable adjustment, carboxymethyl-lysine, 3-deoxyglucosone hydroimidazolones and a summary variable of all measured AGEs (principal component 1) were significantly associated with incident CVD in the Cardiovascular Health Study (HRs [95% CI]: 1.20 [1.01, 1.42], 1.45 [1.23, 1.72], and 1.29 [1.06, 1.56], respectively), but not the Multi-Ethnic Study of Atherosclerosis. Oxidative products were not associated with CVD in either cohort. Conclusions We found α-dicarbonyl-derived AGEs to be associated with CVD in an older cohort, but not in a healthier middle-aged/older cohort. Our results suggest that AGEs may exert detrimental cardiovascular effects only under conditions of marked dicarbonyl and oxidative stress. Further investigation of α-dicarbonyl derivatives could lead to potential new strategies for CVD prevention in high-risk older populations.
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Affiliation(s)
- Julio A Lamprea-Montealegre
- Cardiology Section San Francisco Veterans Affairs Health Care System San Francisco CA.,Kidney Health Research Collaborative San Francisco Veterans Affairs Health Care System and University of California San Francisco CA.,Department of Medicine University of California San Francisco CA
| | - Alice M Arnold
- Department of Biostatistics, School of Public Health University of Washington Seattle WA
| | - Robyn L McCLelland
- Department of Biostatistics, School of Public Health University of Washington Seattle WA
| | - Kenneth J Mukamal
- Department of Medicine Beth Israel Deaconess Medical Center and Harvard Medical School Boston MA
| | - Luc Djousse
- Division of Aging, Department of Medicine Brigham and Women's Hospital and Harvard Medical School Boston MA
| | - Mary L Biggs
- Department of Biostatistics, School of Public Health University of Washington Seattle WA
| | | | - Russell P Tracy
- Department of Pathology and Laboratory Medicine University of Vermont College of Medicine Burlington VT
| | | | - Bruce M Psaty
- Cardiovascular Health Research Unit, Department of Medicine, Epidemiology and Health Services University of Washington Seattle WA
| | - Joachim H Ix
- Division of Nephrology, Department of Medicine University of California San Diego CA
| | - Jorge R Kizer
- Cardiology Section San Francisco Veterans Affairs Health Care System San Francisco CA.,Department of Medicine University of California San Francisco CA.,Department of Epidemiology and Biostatistics University of California San Francisco CA
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Dicarbonyl stress, protein glycation and the unfolded protein response. Glycoconj J 2021; 38:331-340. [PMID: 33644826 PMCID: PMC8116241 DOI: 10.1007/s10719-021-09980-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 01/26/2021] [Accepted: 02/10/2021] [Indexed: 12/22/2022]
Abstract
The reactive dicarbonyl metabolite, methylglyoxal (MG), is increased in obesity and diabetes and is implicated in the development of insulin resistance, type 2 diabetes mellitus and vascular complications of diabetes. Dicarbonyl stress is the metabolic state of abnormal high MG concentration. MG is an arginine-directed glycating agent and precursor of the major advanced glycation endproduct, arginine-derived hydroimidazolone MG-H1. MG-H1 is often formed on protein surfaces and an uncharged hydrophobic residue, inducing protein structural distortion and misfolding. Recent studies indicate that dicarbonyl stress in human endothelial cells and fibroblasts in vitro induced a proteomic response consistent with activation of the unfolded protein response (UPR). The response included: increased abundance of heat shock proteins and ubiquitin ligases catalysing the removal of proteins with unshielded surface hydrophobic patches and formation of polyubiquitinated chains to encapsulate misfolded proteins; and increased low grade inflammation. Activation of the UPR is implicated in insulin resistance. An effective strategy to counter increased MG is inducing increased expression of glyoxalase-1 (Glo1). An optimized inducer of Glo1 expression, trans-resveratrol and hesperetin combination, normalized increased MG concentration, corrected insulin resistance and decreased low grade inflammation in overweight and obese subjects. We propose that dicarbonyl stress, through increased formation of MG-glycated proteins, may be an important physiological stimulus of the UPR and Glo1 inducers may provide a route to effective suppression and therapy. With further investigation and validation, this may provide key new insight into physiological activators of the UPR and association with dicarbonyl stress.
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Methylglyoxal – An emerging biomarker for diabetes mellitus diagnosis and its detection methods. Biosens Bioelectron 2019; 133:107-124. [DOI: 10.1016/j.bios.2019.03.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/07/2019] [Accepted: 03/07/2019] [Indexed: 02/07/2023]
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7
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Perween S, Abidi M, Faizy AF, Moinuddin. Post-translational modifications on glycated plasma fibrinogen: A physicochemical insight. Int J Biol Macromol 2019; 126:1201-1212. [DOI: 10.1016/j.ijbiomac.2019.01.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 12/11/2018] [Accepted: 01/04/2019] [Indexed: 12/29/2022]
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Advanced glycation end products in the pathogenesis of chronic kidney disease. Kidney Int 2018; 93:803-813. [DOI: 10.1016/j.kint.2017.11.034] [Citation(s) in RCA: 142] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 10/15/2017] [Accepted: 11/09/2017] [Indexed: 12/11/2022]
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Hansen NW, Hansen AJ, Sams A. The endothelial border to health: Mechanistic evidence of the hyperglycemic culprit of inflammatory disease acceleration. IUBMB Life 2017; 69:148-161. [PMID: 28230336 DOI: 10.1002/iub.1610] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 01/21/2017] [Indexed: 02/06/2023]
Abstract
The endothelial cell (EC) layer constitutes a barrier that controls movements of fluid, solutes and cells between blood and tissue. Further, the endothelial layer regulates vascular tone and directs local humoral and cellular inflammatory processes. The strategic position makes it an important player for maintenance of health and for development of a number of diseases. Endothelial dysfunction is known to be an important component of type 2 diabetes, but is also assumed to be involved in many other diseases, for example, rheumatoid arthritis, inflammatory bowel disease, asthma, and cardiovascular diseases. We here suggest that the EC plays a pivotal role in disease pathophysiology through initiation, potentiation, and maintenance of several inflammatory mechanisms. Our contention is based on the observation that hyperglycemia-intermittent or sustained, local or systemic-is a major culprit for several endothelial dysfunctions. There is also mounting epidemiological evidence that dietary intake of refined sugars is important for the development of a number of diseases beyond obesity and type 2 diabetes. Various diseases involving inflammatory and immunological components are accelerated by hyperglycemic events because the endothelium transduces "high glucose" signaling into significant pathophysiological phenomena leading to reduced endothelial barrier function, compromised vascular tone regulation and inflammation (e.g., cytokine secretion and RAGE activation). In addition, endothelial extracellular proteins form epitopes for potential specific antibody formation upon interactions with reducing sugars. This paper reviews the endothelial metabolism, biology, inflammatory processes, physical barrier functions, and summarizes evidence that although stochastic in nature, endothelial responses to hyperglycemia are major contributors to disease pathophysiology. We present molecular and mechanistic evidence that both biological and physical barriers, protein function, specific immunity, and inflammatory processes are compromised by hyperglycemic events and thus, hyperglycemic events alone should be considered risk factors for numerous human diseases. © 2017 IUBMB Life, 69(3):148-161, 2017.
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Affiliation(s)
- Nina Waerling Hansen
- Department of Endocrinology (Diabetes and Metabolism), Rigshospitalet, Copenhagen, Denmark
| | - Anker Jon Hansen
- Center for Basic and Translational Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Anette Sams
- Department of Clinical Experimental Research, Glostrup Research Institute, Copenhagen University Hospital, Rigshospitalet, Glostrup, Denmark
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10
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Abstract
The glyoxalase system in the cytoplasm of cells provides the primary defence against glycation by methylglyoxal catalysing its metabolism to D-lactate. Methylglyoxal is the precursor of the major quantitative advanced glycation endproducts in physiological systems - arginine-derived hydroimidazolones and deoxyguanosine-derived imidazopurinones. Glyoxalase 1 of the glyoxalase system was linked to anthropometric measurements of obesity in human subjects and to body weight in strains of mice. Recent conference reports described increased weight gain on high fat diet-fed mouse with lifelong deficiency of glyoxalase 1 deficiency, compared to wild-type controls, and decreased weight gain in glyoxalase 1-overexpressing transgenic mice, suggesting a functional role of glyoxalase 1 and dicarbonyl stress in obesity. Increased methylglyoxal, dicarbonyl stress, in white adipose tissue and liver may be a mediator of obesity and insulin resistance and thereby a risk factor for development of type 2 diabetes and non-alcoholic fatty liver disease. Increased methylglyoxal formation from glyceroneogenesis on adipose tissue and liver and decreased glyoxalase 1 activity in obesity likely drives dicarbonyl stress in white adipose tissue increasing the dicarbonyl proteome and related dysfunction. The clinical significance will likely emerge from on-going clinical evaluation of inducers of glyoxalase 1 expression in overweight and obese subjects. Increased transcapillary escape rate of albumin and increased total body interstitial fluid volume in obesity likely makes levels of glycation of plasma protein unreliable indicators of glycation status in obesity as there is a shift of albumin dwell time from plasma to interstitial fluid, which decreases overall glycation for a given glycemic exposure.
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Gajjala PR, Fliser D, Speer T, Jankowski V, Jankowski J. Emerging role of post-translational modifications in chronic kidney disease and cardiovascular disease. Nephrol Dial Transplant 2015; 30:1814-1824. [DOI: 10.1093/ndt/gfv048] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Hansen F, Battú CE, Dutra MF, Galland F, Lirio F, Broetto N, Nardin P, Gonçalves CA. Methylglyoxal and carboxyethyllysine reduce glutamate uptake and S100B secretion in the hippocampus independently of RAGE activation. Amino Acids 2015; 48:375-85. [PMID: 26347375 DOI: 10.1007/s00726-015-2091-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 08/28/2015] [Indexed: 01/29/2023]
Abstract
Diabetes is a metabolic disease characterized by high fasting-glucose levels. Diabetic complications have been associated with hyperglycemia and high levels of reactive compounds, such as methylglyoxal (MG) and advanced glycation endproducts (AGEs) formation derived from glucose. Diabetic patients have a higher risk of developing neurodegenerative diseases, such as Alzheimer's disease or Parkinson's disease. Herein, we examined the effect of high glucose, MG and carboxyethyllysine (CEL), a MG-derived AGE of lysine, on oxidative, metabolic and astrocyte-specific parameters in acute hippocampal slices, and investigated some of the mechanisms that could mediate these effects. Glucose, MG and CEL did not alter reactive oxygen species (ROS) formation, glucose uptake or glutamine synthetase activity. However, glutamate uptake and S100B secretion were decreased after MG and CEL exposure. RAGE activation and glycation reactions, examined by aminoguanidine and L-lysine co-incubation, did not mediate these changes. Acute MG and CEL exposure, but not glucose, were able to induce similar effects on hippocampal slices, suggesting that conditions of high glucose concentrations are primarily toxic by elevating the rates of these glycation compounds, such as MG, and by generation of protein cross-links. Alterations in the secretion of S100B and the glutamatergic activity mediated by MG and AGEs can contribute to the brain dysfunction observed in diabetic patients.
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Affiliation(s)
- Fernanda Hansen
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Cíntia Eickhoff Battú
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Márcio Ferreira Dutra
- Departamento de Biologia Celular, Embriologia e Genética, Centro de Ciências Biológicas, Universidade Federal de Santa Catarina, Campus Trindade, Florianópolis, SC, 88040-970, Brazil
| | - Fabiana Galland
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Franciane Lirio
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Núbia Broetto
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, 90046-900, Brazil
| | - Patrícia Nardin
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil
| | - Carlos-Alberto Gonçalves
- Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Ramiro Barcelos, 2600-Anexo, Porto Alegre, RS, 90035-003, Brazil.
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Abstract
Methylglyoxal is a potent protein-glycating agent. It is an arginine-directed glycating agent and often modifies functionally important sites in proteins. Glycation forms mainly MG-H1 [Nδ-(5-hydro-5-methyl-4-imidazolon-2-yl)ornithine] residues. MG-H1 content of proteins is quantified by stable isotopic dilution analysis-MS/MS and also by immunoblotting with specific monoclonal antibodies. Methylglyoxal-modified proteins undergo cellular proteolysis and release MG-H1 free adduct for excretion. MG-H1 residues have been found in proteins of animals, plants, bacteria, fungi and protoctista. MG-H1 is often the major advanced glycation end-product in proteins of tissues and body fluids, increasing in diabetes and associated vascular complications, renal failure, cirrhosis, Alzheimer's disease, arthritis, Parkinson's disease and aging. Proteins susceptible to methylglyoxal modification with related functional impairment are called the DCP (dicarbonyl proteome). The DCP includes albumin, haemoglobin, transcription factors, mitochondrial proteins, extracellular matrix proteins, lens crystallins and others. DCP component proteins are linked to mitochondrial dysfunction in diabetes and aging, oxidative stress, dyslipidaemia, cell detachment and anoikis and apoptosis. Methylglyoxal also modifies DNA where deoxyguanosine residues are modified to imidazopurinone MGdG {3-(2'-deoxyribosyl)-6,7-dihydro-6,7-dihydroxy-6/7-methylimidazo-[2,3-b]purine-9(8)one} isomers. MGdG was the major quantitative adduct detected in vivo. It was linked to frequency of DNA strand breaks and increased markedly during apoptosis induced by a cell-permeant glyoxalase I inhibitor. Glyoxalase I metabolizes >99% methylglyoxal and thereby protects the proteome and genome. Gene deletion of GLO1 is embryonically lethal and GLO1 silencing increases methylglyoxal concentration, MG-H1 and MGdG, premature aging and disease. Studies of methylglyoxal glycation have importance for human health, longevity and treatment of disease.
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Brown KL, Darris C, Rose KL, Sanchez OA, Madu H, Avance J, Brooks N, Zhang MZ, Fogo A, Harris R, Hudson BG, Voziyan P. Hypohalous acids contribute to renal extracellular matrix damage in experimental diabetes. Diabetes 2015; 64:2242-53. [PMID: 25605804 PMCID: PMC4439565 DOI: 10.2337/db14-1001] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 01/10/2015] [Indexed: 12/17/2022]
Abstract
In diabetes, toxic oxidative pathways are triggered by persistent hyperglycemia and contribute to diabetes complications. A major proposed pathogenic mechanism is the accumulation of protein modifications that are called advanced glycation end products. However, other nonenzymatic post-translational modifications may also contribute to pathogenic protein damage in diabetes. We demonstrate that hypohalous acid-derived modifications of renal tissues and extracellular matrix (ECM) proteins are significantly elevated in experimental diabetic nephropathy. Moreover, diabetic renal ECM shows diminished binding of α1β1 integrin consistent with the modification of collagen IV by hypochlorous (HOCl) and hypobromous acids. Noncollagenous (NC1) hexamers, key connection modules of collagen IV networks, are modified via oxidation and chlorination of tryptophan and bromination of tyrosine residues. Chlorotryptophan, a relatively minor modification, has not been previously found in proteins. In the NC1 hexamers isolated from diabetic kidneys, levels of HOCl-derived oxidized and chlorinated tryptophan residues W(28) and W(192) are significantly elevated compared with nondiabetic controls. Molecular dynamics simulations predicted a more relaxed NC1 hexamer tertiary structure and diminished assembly competence in diabetes; this was confirmed using limited proteolysis and denaturation/refolding. Our results suggest that hypohalous acid-derived modifications of renal ECM, and specifically collagen IV networks, contribute to functional protein damage in diabetes.
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Affiliation(s)
- Kyle L Brown
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Carl Darris
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | | | - Otto A Sanchez
- Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN
| | - Hartman Madu
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | | | | | - Ming-Zhi Zhang
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Agnes Fogo
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN
| | - Raymond Harris
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
| | - Billy G Hudson
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN Department of Biochemistry, Vanderbilt University Medical Center, Nashville, TN Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN
| | - Paul Voziyan
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN
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15
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Affiliation(s)
- Naila Rabbani
- Clinical Sciences Research Laboratories, Warwick Medical School, University of Warwick, University Hospital, Coventry, U.K
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16
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Leeming DJ, Karsdal MA, Rasmussen LM, Scholze A, Tepel M. Association of systemic collagen type IV formation with survival among patients undergoing hemodialysis. PLoS One 2013; 8:e71050. [PMID: 23990924 PMCID: PMC3750054 DOI: 10.1371/journal.pone.0071050] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2013] [Accepted: 06/24/2013] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE The 7S domain of collagen type IV (P4NP_7S) assessed in plasma represents systemic collagen type IV formation. The objective of the study was to investigate the association of systemic collagen type IV formation with survival among patients undergoing hemodialysis. METHODS We performed an observational cohort study of 371 hemodialysis patients. Plasma P4NP_7S was analyzed using a specific enzyme-linked immunosorbent assay detecting the amino-terminal propeptide of type IV procollagen. Association between categories of plasma P4NP_7S concentrations and survival was initially assessed by Kaplan-Meier analysis, then in an adjusted Cox model. RESULTS For hemodialysis patients in the highest category of systemic collagen type IV formation, i.e. plasma P4NP_7S concentrations more than 775 pg/L, an increased risk for death was observed (highest P4NP_7S category vs all other categories, hazard ratio, 1.934; 95% confidence interval, 1.139 to 3.285). Survival analysis showed an increased risk of death in the highest P4NP_7S category compared to the other categories (Chi square 6.903; P = 0.032). Median survival was only 105 days in the highest P4NP_7S category whereas it was 629 days in the medium category, and 905 days in the lowest category. Multivariable-adjusted Cox regression showed increased odds for death with higher age and higher P4NP_7S categories. Systemic collagen type IV formation was associated with plasma concentrations of the collagen IV degradation product C4M (Spearman r = 0.764; P<0.0001) confirming extracellular matrix turnover. CONCLUSION Among hemodialysis patients elevated systemic collagen type IV formation suggesting accelerating systemic fibrosis was associated with increased risk of death.
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Affiliation(s)
| | | | - Lars M. Rasmussen
- Odense University Hospital, Department of Clinical Biochemistry and Pharmacology, Odense, Denmark
| | - Alexandra Scholze
- Odense University Hospital, Department of Nephrology, Institute for Molecular Medicine, Cardiovascular and Renal Research, Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Martin Tepel
- Odense University Hospital, Department of Nephrology, Institute for Molecular Medicine, Cardiovascular and Renal Research, Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
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Meltretter J, Wüst J, Pischetsrieder M. Comprehensive analysis of nonenzymatic post-translational β-lactoglobulin modifications in processed milk by ultrahigh-performance liquid chromatography-tandem mass spectrometry. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2013; 61:6971-6981. [PMID: 23772976 DOI: 10.1021/jf401549j] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Nonenzymatic post-translational protein modifications (nePTMs) result in changes of the protein structure that may severely influence physiological and technological protein functions. In the present study, ultrahigh-performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) was applied for the systematic identification and site-specific analysis of nePTMs of β-lactoglobulin in processed milk. For this purpose, β-lactoglobulin, which had been heated with lactose under conditions to force nePTM formation (7 d/60 °C), was screened for predicted modifications by using full scans and enhanced resolution scan experiments combined with enhanced product ion scans. Thus, the main glycation, glycoxidation, oxidation, and deamidation products of lysine, arginine, methionine, cysteine, tryptophan, and asparagine, as well as the N-terminus, were identified. Using these MS data, a very sensitive scheduled multiple reaction monitoring method suitable for the analysis of milk products was developed. Consequently, 14 different PTM structures on 25 binding sites of β-lactoglobulin were detected in different milk products.
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Affiliation(s)
- Jasmin Meltretter
- Department of Chemistry and Pharmacy, Chair of Food Chemistry, Emil Fischer Center, University of Erlangen-Nuremberg, Erlangen, Germany
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Fleming TH, Theilen TM, Masania J, Wunderle M, Karimi J, Vittas S, Bernauer R, Bierhaus A, Rabbani N, Thornalley PJ, Kroll J, Tyedmers J, Nawrotzki R, Herzig S, Brownlee M, Nawroth PP. Aging-dependent reduction in glyoxalase 1 delays wound healing. Gerontology 2013; 59:427-37. [PMID: 23797271 DOI: 10.1159/000351628] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2012] [Accepted: 04/22/2013] [Indexed: 11/19/2022] Open
Abstract
Methylglyoxal (MG), the major dicarbonyl substrate of the enzyme glyoxalase 1 (GLO1), is a reactive metabolite formed via glycolytic flux. Decreased GLO1 activity in situ has been shown to result in an accumulation of MG and increased formation of advanced glycation endproducts, both of which can accumulate during physiological aging and at an accelerated rate in diabetes and other chronic degenerative diseases. To determine the physiological consequences which result from elevated MG levels and the role of MG and GLO1 in aging, wound healing in young (≤12 weeks) and old (≥52 weeks) wild-type mice was studied. Old mice were found to have a significantly slower rate of wound healing compared to young mice (74.9 ± 2.2 vs. 55.4 ± 1.5% wound closure at day 6; 26% decrease; p < 0.0001). This was associated with decreases in GLO1 transcription, expression and activity. The importance of GLO1 was confirmed in mice by inhibition of GLO1. Direct application of MG to the wounds of young mice, decreased wound healing by 24% compared to untreated mice, whereas application of BSA modified minimally by MG had no effect. Treatment of either young or old mice with aminoguanidine, a scavenger of free MG, significantly increased wound closure by 16% (66.8 ± 1.6 vs. 77.2 ± 3.1%; p < 0.05) and 64% (40.4 ± 7.9 vs. 66.4 ± 5.2%; p < 0.05), respectively, by day 6. As a result of the aminoguanidine treatment, the overall rate of wound healing in the old mice was restored to the level observed in the young mice. These findings were confirmed in vitro, as MG reduced migration and proliferation of fibroblasts derived from young and old, wild-type mice. The data demonstrate that the balance between MG and age-dependent GLO1 downregulation contributes to delayed wound healing in old mice.
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Affiliation(s)
- Thomas H Fleming
- Department of Medicine I and Clinical Chemistry, University of Heidelberg, Heidelberg, Germany
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Targeted complement inhibition as a promising strategy for preventing inflammatory complications in hemodialysis. Immunobiology 2013; 217:1097-105. [PMID: 22964235 DOI: 10.1016/j.imbio.2012.07.012] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2012] [Accepted: 07/17/2012] [Indexed: 01/10/2023]
Abstract
Hemodialysis is the most common method used to remove waste and hazardous products of metabolism in patients suffering from renal failure. Hundreds of thousands of people with end-stage renal disease undergo hemodialysis treatment in the United States each year. Strikingly, the 5-year survival rate for all dialysis patients is only 35%. Most of the patients succumb to cardiovascular disease that is exacerbated by the chronic induction of inflammation caused by contact of the blood with the dialysis membrane. The complement system, a strong mediator of pro-inflammatory networks, is a key contributor to such biomaterial-induced inflammation. Though only evaluated in experimental ex vivo settings, specific targeting of complement activation during hemodialysis has uncovered valuable information that points toward the therapeutic use of complement inhibitors as a means to control the unwelcomed inflammatory responses and consequent pathologies in hemodialysis patients.
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20
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Scholze A, Bladbjerg EM, Sidelmann JJ, Diederichsen ACP, Mickley H, Nybo M, Argraves WS, Marckmann P, Rasmussen LM. Plasma concentrations of extracellular matrix protein fibulin-1 are related to cardiovascular risk markers in chronic kidney disease and diabetes. Cardiovasc Diabetol 2013; 12:6. [PMID: 23294625 PMCID: PMC3570481 DOI: 10.1186/1475-2840-12-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Accepted: 01/03/2013] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Fibulin-1 is one of a few extracellular matrix proteins present in blood in high concentrations. We aimed to define the relationship between plasma fibulin-1 levels and risk markers of cardiovascular disease. METHODS Plasma fibulin-1 was determined in subjects with chronic kidney disease (n = 32; median age 62.5, inter-quartile range 51 - 73 years) and 60 age-matched control subjects. Among kidney disease patients serological biomarkers related to cardiovascular disease (fibrinogen, interleukin 6, C-reactive protein) were measured. Arterial applanation tonometry was used to determine central hemodynamic and arterial stiffness indices. RESULTS We observed a positive correlation of fibulin-1 levels with age (r = 0.38; p = 0.033), glycated hemoglobin (r = 0.80; p = 0.003), creatinine (r = 0.35; p = 0.045), and fibrinogen (r = 0.39; p = 0.027). Glomerular filtration rate and fibulin-1 were inversely correlated (r = -0.57; p = 0.022). There was a positive correlation between fibulin-1 and central pulse pressure (r = 0.44; p = 0.011) and central augmentation pressure (r = 0.55; p = 0.001). In a multivariable regression model, diabetes, creatinine, fibrinogen and central augmentation pressure were independent predictors of plasma fibulin-1. CONCLUSION Increased plasma fibulin-1 levels were associated with diabetes and impaired kidney function. Furthermore, fibulin-1 levels were associated with hemodynamic cardiovascular risk markers. Fibulin-1 is a candidate in the pathogenesis of cardiovascular disease observed in chronic kidney disease and diabetes.
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Affiliation(s)
- Alexandra Scholze
- Clinical Research Unit, Department of Nephrology, Odense University Hospital, Odense, Denmark.
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21
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Piroddi M, Bartolini D, Ciffolilli S, Galli F. Nondialyzable Uremic Toxins. Blood Purif 2013; 35 Suppl 2:30-41. [DOI: 10.1159/000350846] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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Metabolic syndrome: a novel high-risk state for colorectal cancer. Cancer Lett 2012; 334:56-61. [PMID: 23085010 DOI: 10.1016/j.canlet.2012.10.012] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2012] [Revised: 10/10/2012] [Accepted: 10/10/2012] [Indexed: 12/17/2022]
Abstract
Metabolic syndrome (MS) and related disorders, including cancer, are steadily increasing in most countries of the world. However, mechanisms underlying the link between MS and colon carcinogenesis have yet to be fully elucidated. In this review article we focus on the relationships between various individual associated conditions (obesity, dyslipidemia, diabetes mellitus type 2 and hypertension) and colon cancer development, and demonstrate probable related factors revealed by in vivo and in vitro studies. Furthermore, molecules suggested to be involved in cancer promotion are addressed, and the potential for cancer prevention by targeting these molecules is discussed.
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Taddei ML, Giannoni E, Fiaschi T, Chiarugi P. Anoikis: an emerging hallmark in health and diseases. J Pathol 2012; 226:380-93. [PMID: 21953325 DOI: 10.1002/path.3000] [Citation(s) in RCA: 399] [Impact Index Per Article: 33.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Anoikis is a programmed cell death occurring upon cell detachment from the correct extracellular matrix, thus disrupting integrin ligation. It is a critical mechanism in preventing dysplastic cell growth or attachment to an inappropriate matrix. Anoikis prevents detached epithelial cells from colonizing elsewhere and is thus essential for tissue homeostasis and development. As anchorage-independent growth and epithelial-mesenchymal transition, two features associated with anoikis resistance, are crucial steps during tumour progression and metastatic spreading of cancer cells, anoikis deregulation has now evoked particular attention from the scientific community. The aim of this review is to analyse the molecular mechanisms governing both anoikis and anoikis resistance, focusing on their regulation in physiological processes, as well as in several diseases, including metastatic cancers, cardiovascular diseases and diabetes.
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Affiliation(s)
- M L Taddei
- Department of Biochemical Sciences, University of Florence, and Tumour Institute and Centre for Research, Transfer and High Education DenoTHE, Florence, Italy
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Inhibiting TRPA1 ion channel reduces loss of cutaneous nerve fiber function in diabetic animals: sustained activation of the TRPA1 channel contributes to the pathogenesis of peripheral diabetic neuropathy. Pharmacol Res 2011; 65:149-58. [PMID: 22133672 DOI: 10.1016/j.phrs.2011.10.006] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 10/21/2011] [Accepted: 10/22/2011] [Indexed: 11/24/2022]
Abstract
Peripheral diabetic neuropathy (PDN) is a devastating complication of diabetes mellitus (DM). Here we test the hypothesis that the transient receptor potential ankyrin 1 (TRPA1) ion channel on primary afferent nerve fibers is involved in the pathogenesis of PDN, due to sustained activation by reactive compounds generated in DM. DM was induced by streptozotocin in rats that were treated daily for 28 days with a TRPA1 channel antagonist (Chembridge-5861528) or vehicle. Laser Doppler flow method was used for assessing axon reflex induced by intraplantar injection of a TRPA1 channel agonist (cinnamaldehyde) and immunohistochemistry to assess substance P-like innervation of the skin. In vitro calcium imaging and patch clamp were used to assess whether endogenous TRPA1 agonists (4-hydroxynonenal and methylglyoxal) generated in DM induce sustained activation of the TRPA1 channel. Axon reflex induced by a TRPA1 channel agonist in the plantar skin was suppressed and the number of substance P-like immunoreactive nerve fibers was decreased 4 weeks after induction of DM. Prolonged treatment with Chembridge-5861528 reduced the DM-induced attenuation of the cutaneous axon reflex and loss of substance P-like immunoreactive nerve fibers. Moreover, in vitro calcium imaging and patch clamp results indicated that reactive compounds generated in DM (4-hydroxynonenal and methylglyoxal) produced sustained activations of the TRPA1 channel, a prerequisite for adverse long-term effects. The results indicate that the TRPA1 channel exerts an important role in the pathogenesis of PDN. Blocking the TRPA1 channel provides a selective disease-modifying treatment of PDN.
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Selmeci L. Advanced oxidation protein products (AOPP): novel uremic toxins, or components of the non-enzymatic antioxidant system of the plasma proteome? Free Radic Res 2011; 45:1115-23. [DOI: 10.3109/10715762.2011.602074] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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26
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Rabbani N, Thornalley PJ. Glyoxalase in diabetes, obesity and related disorders. Semin Cell Dev Biol 2011; 22:309-17. [PMID: 21335095 DOI: 10.1016/j.semcdb.2011.02.015] [Citation(s) in RCA: 183] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 02/04/2011] [Accepted: 02/10/2011] [Indexed: 01/21/2023]
Abstract
Diabetes was the first disease state where evidence emerged for increased formation of methylglyoxal. Metabolism of methylglyoxal by the glyoxalase system has been linked to the development of vascular complications of diabetes - nephropathy, retinopathy, neuropathy and cardiovascular disease. Increased formation of methylglyoxal in hyperglycaemia associated with diabetes and down regulation of glyoxalase 1 by inflammatory signalling in vascular cells leads to a marked increased modification of proteins by methylglyoxal to form advanced glycation endproducts at the sites of vascular complications. Hotspot protein targets of methylglyoxal that suffer functional impairment - the dicarbonyl proteome - likely play a key role in the mechanisms underlying the development of vascular complications in diabetes: particularly modification of integrin binding sites in extracellular matrix proteins leading to endothelial cell shedding and anoikis, modification of mitochondrial proteins and increased formation of reaction oxygen species, and modification of apolipoprotein B100 of low density lipoprotein leading to its increased atherogenicity. Some current therapeutic agents counter partially dysfunctional metabolism of methylglyoxal by the glyoxalase system in diabetes - including the recent development of high dose thiamine therapy for early stage diabetic nephropathy. Further pharmacologic strategies are required to overcome the down regulation of glyoxalase1 in diabetes. The glyoxalase system is likely to be a continuing and future focus for research on clinical biomarkers and therapeutic development for respectively assessment of metabolic control and prevention of vascular complications in diabetes and obesity.
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Affiliation(s)
- Naila Rabbani
- Clinical Sciences Research Institute, Warwick Medical School, University of Warwick, University Hospital, Coventry, UK.
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