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Chirality Apr 2020Chronic obstructive pulmonary disease (COPD) is a degenerative condition with limited diagnostic detection efficiency. Currently with no available cure, COPD is...
Chronic obstructive pulmonary disease (COPD) is a degenerative condition with limited diagnostic detection efficiency. Currently with no available cure, COPD is associated with irreversible elastic tissue degradation in lungs, which results in release of unusual amino acids, isodesmosine and desmosine. These biomarkers are potential key elements in enzyme-linked immunosorbent assay (ELISA), an analytical method, which can detect certain compounds including antigens and proteins in easy and affordable manner. In order to target a biomarker with ELISA, it is necessary to prepare its specific antibody, which can be achieved by immunization of host organism with appropriate antigen containing the biomarker. Although preparation of these types of conjugates has been published, desmosine and isodesmosine used by researchers are obtained from natural sources such as animal tissues. Here, we report the first synthetic preparation of isodesmosine and keyhole limpet hemocyanin (KLH) conjugate from commercially available chiral amino acids and carrier protein. Formation of the core pyridinium of isodesmosine was achieved through key reaction-Chichibabin pyridinium synthesis-to deliver a 1,2,3,5-tetrasubstituted pyridinium amino acid selectively. Further modifications involving KLH and maleimide linker provided the target conjugate, which could potentially invoke an immune response to produce anti-isodesmosine antibody for the ELISA system.
Topics: Biomarkers; Enzyme-Linked Immunosorbent Assay; Hemocyanins; Isodesmosine; Pulmonary Disease, Chronic Obstructive; Stereoisomerism
PubMed: 32027414
DOI: 10.1002/chir.23175 -
Acta Biomaterialia Mar 2020Intrinsically poor auto-regenerative repair of proteolytically-disrupted elastic matrix structures by resident SMCs in the wall of abdominal aortic aneurysms (AAAs)...
Intrinsically poor auto-regenerative repair of proteolytically-disrupted elastic matrix structures by resident SMCs in the wall of abdominal aortic aneurysms (AAAs) prevents growth arrest and regression of these wall expansions. Supporting their possible future use in a regenerative cell therapy for AAAs, in a prior study, we showed that bone marrow mesenchymal stem cell-derived Smooth Muscle Cells (BM-SMCs) secrete biological factors that have significant pro-elastogenic and anti-proteolytic effects on aneurysmal rat aortic SMCs (EaRASMCs) in non-contact co-cultures. We also identified one stable BM-SMC phenotype (cBM-SMC) generated by differentiating BM-MSCs on a 2D fibronectin substrate in the presence of PDGF (Platelet Derived Growth Factor) and TGF-β1 (Transforming Growth Factor-β1) that exhibited superior elastogenicity and pro-elastogenic/anti-proteolytic properties. In this study, we further investigated the ability of these cBM-SMCs to maintain these superior elastogenic properties in a 3D collagenous milieu alone and in co-culture with EaRASMC to evaluate their potential as an alternative cell source for cell therapy in AAA. Some of our key observations were higher contractility and greater amount of structurally intact elastin production in both standalone culture of cBM-SMCs as well as co-culture of cBM-SMCs with EaRASMCs as shown by VVG (Verhoeff-Van Gieson) staining and Pontamine Sky Blue labeling and lower MMP-9 protein expression in standalone culture in 3D collagenous environment. Our overall result indicates that cBM-SMCs possess the ability to provide elastogenic impetus in a 3D collagenous AAA milieu which is otherwise not conducive to elastogenesis. Therefore our study strongly suggest the utility of cBM-SMCs as a potential cell source for cell therapy to augment elastic matrix neo-assembly and fiber formation and attenuate proteolysis in a collagenous milieu that is evocative of the de-elasticized aneurysmal wall. STATEMENT OF SIGNIFICANCE: Abdominal aortic aneurysm (AAA) or ballooning of the aorta is one of the leading causes of cardiovascular disease (CVD) related death caused by significantly increased proteolytic activity in the aortic wall. Reversing pathophysiology of this condition is challenging due to intrinsically poor regeneration of elastin by aortic smooth muscle cells. Current management of AAA is limited to passive monitoring of the disease until it becomes large enough to receive surgical intervention and no drug based therapy currently exists. Cell based therapy can be a potential alternative treatment in this scenario because it provides elastogenic impetus to the aneurysmal SMCs, compensates for the dead SMCs and serves as a robust source of elastin while being delivered with minimal invasiveness. Hence this work will have significant impact in the field of tissue engineering and regenerative medicine.
Topics: Animals; Cell Proliferation; Cell Survival; Collagen; Desmosine; Elasticity; Elastin; Extracellular Matrix; Fluorescence; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mesenchymal Stem Cells; Myocytes, Smooth Muscle; Proteolysis; Rats, Sprague-Dawley; Tissue Scaffolds
PubMed: 31982591
DOI: 10.1016/j.actbio.2020.01.030 -
ERJ Open Research Oct 2019Electronic cigarettes (e-cigs) were introduced as electronic nicotine delivery systems, and have become very popular in the USA and globally. There is a paucity of data...
BACKGROUND
Electronic cigarettes (e-cigs) were introduced as electronic nicotine delivery systems, and have become very popular in the USA and globally. There is a paucity of data on systemic injury biomarkers of vaping in e-cig users that can be used as a noninvasive assessment of vaping-associated lung injuries. We hypothesised that characterisation of systemic biomarkers of inflammation, anti-inflammatory, oxidative stress, vascular and lipid mediators, growth factors, and extracellular matrix breakdown may provide information regarding the toxicity of vaping in e-cig users.
METHODS
We collected various biological fluids, plasma, urine, saliva and exhaled breath condensate (EBC), measured pulmonary function and vaping characteristics, and assessed various biomarkers in e-cig users and nonusers.
RESULTS
The plasma samples of e-cig users showed a significant increase in biomarkers of inflammation (interleukin (IL)-1β, IL-6, IL-8, IL-13, interferon (IFN)-γ, matrix metalloproteinase-9, intercellular cell adhesion molecule-1) and extracellular matrix breakdown (desmosine), and decreased pro-resolving lipid mediators (resolvin D and resolvin D). There was a significant increase in growth factor (endothelial growth factor, vascular endothelial growth factor, β-nerve growth factor, platelet-derived growth factor-AA, stem cell factor, hepatocyte growth factor and placental growth factor) levels in plasma of e-cig users nonusers. E-cig users showed a significant increase in levels of inflammatory biomarker IFN-γ, oxidative stress biomarker 8-isoprostane and oxidative DNA damage biomarker 8-oxo-dG in urine samples, and of inflammatory biomarker IL-1β in saliva samples. EBC showed a slight increase in levels of triglycerides and 8-isoprostane in e-cig users compared with normal nonusers.
CONCLUSION
E-cig users have increased levels of biomarkers of inflammation and oxidative stress, reduced pro-resolving anti-inflammatory mediators, and endothelial dysfunction, which may act as risk factors for increasing susceptibility to systemic diseases. The identified noninvasive biomarkers can be used for determining e-cig vaping-associated lung injuries, and for regulatory and diagnostic aspects of vaping in humans.
PubMed: 31886159
DOI: 10.1183/23120541.00182-2019 -
IUBMB Life May 2020Elastic fibers are essential assemblies of vertebrates and confer elasticity and resilience to various organs including blood vessels, lungs, skin, and ligaments. Mature... (Review)
Review
Elastic fibers are essential assemblies of vertebrates and confer elasticity and resilience to various organs including blood vessels, lungs, skin, and ligaments. Mature fibers, which comprise a dense and insoluble elastin core and a microfibrillar mantle, are extremely resistant toward intrinsic and extrinsic influences and maintain elastic function over the human lifespan in healthy conditions. The oxidative deamination of peptidyl lysine to peptidyl allysine in elastin's precursor tropoelastin is a crucial posttranslational step in their formation. The modification is catalyzed by members of the family of lysyl oxidases and the starting point for subsequent manifold condensation reactions that eventually lead to the highly cross-linked elastomer. This review summarizes the current understanding of the formation of cross-links within and between the monomer molecules, the molecular sites, and cross-link types involved and the pathological consequences of abnormalities in the cross-linking process.
Topics: 2-Aminoadipic Acid; Aging; Animals; Blood Vessels; Connective Tissue Diseases; Elastic Tissue; Elastin; Humans; Ligaments; Lung; Lysine; Microfibrils; Oxidation-Reduction; Protein Processing, Post-Translational; Protein-Lysine 6-Oxidase; Skin
PubMed: 31834666
DOI: 10.1002/iub.2213 -
Asian Journal of Andrology 2020This study aimed to explore whether and how anti-lysyl oxidase (anti-LOX) combined with a vacuum device (VD) could promote penile lengthening and to evaluate the effect...
This study aimed to explore whether and how anti-lysyl oxidase (anti-LOX) combined with a vacuum device (VD) could promote penile lengthening and to evaluate the effect on erectile function. This study was performed on four groups of adult rats: control, anti-LOX, VD (negative pressure value of -300 mmHg), and anti-LOX + VD. Penile length was measured by a modified VD method and verified on exposed length data. Intracavernous pressure (ICP) and maximum ICP/mean arterial pressure (MAP) ratio were recorded to assess erectile function. For corpus cavernosum, LOX activity and concentrations of pyridinoline, desmosine, hydroxyproline, and elastin were analyzed; transmission electron microscope and Hart's elastin staining were performed to monitor microstructural changes. Anti-LOX and VD significantly lengthened the penis by 10.8% (3.75 mm) and 8.2% (2.48 mm) compared with the control group, respectively, while anti-LOX + VD achieved the longest penile size (40.58 ± 0.40 mm) which was 17.4% longer than the control group (34.58 ± 0.54 mm). After 1-week washout, no penile retraction was observed. Meanwhile, exposed penile length data confirmed that the penis in the anti-LOX + VD group was also significantly longer. Anti-LOX inhibited LOX activity to reduce pyridinoline level, which led the penile tunica albuginea remodeling. However, it had no effect on hydroxyproline, desmosine, and elastin levels. Moreover, anti-LOX had no impact on erectile function, which was determined by ICP and ICP/MAP ratio. These results suggest that anti-LOX elongates the penis by reducing pyridinoline, which induces tunica albuginea remodeling. This lengthening effect was more obvious when combined with a VD. All procedures had no impact on erectile function.
Topics: Amino Acids; Aminopropionitrile; Animals; Arterial Pressure; Collagen; Combined Modality Therapy; Desmosine; Elastin; Enzyme Inhibitors; Hydroxyproline; Male; Organ Size; Penile Erection; Penis; Protein-Lysine 6-Oxidase; Rats; Rats, Sprague-Dawley; Vacuum
PubMed: 31736474
DOI: 10.4103/aja.aja_120_19 -
Journal of the American Heart... Oct 2019Background It is recognized that factors beyond aortic size are important in predicting outcome in abdominal aortic aneurysm (AAA) disease. AAA is characterized by the... (Observational Study)
Observational Study
Background It is recognized that factors beyond aortic size are important in predicting outcome in abdominal aortic aneurysm (AAA) disease. AAA is characterized by the breakdown of elastin within the aortic tunica media, leading to aortic dilatation and rupture. The aim of this study was to investigate the association of plasma desmosine (pDES), an elastin-specific degradation product, with disease severity and clinical outcome in patients with AAA. Methods and Results We measured pDES and serum biomarker concentrations in 507 patients with AAAs (94% men; mean age, 72.4±6.1 years; mean AAA diameter, 48±8 mm) and 162 control subjects (100% men; mean age, 71.5±4.4 years) from 2 observational cohort studies. In the longitudinal cohort study (n=239), we explored the incremental prognostic value of pDES on AAA events. pDES was higher in patients with AAA compared with control subjects (mean±SD: 0.46±0.22 versus 0.33±0.16 ng/mL; <0.001) and had the strongest correlation with AAA diameter (=0.39; <0.0001) of any serum biomarker. After adjustment for baseline AAA diameter, pDES was associated with an AAA event (hazard ratio, 2.03 per SD increase [95% CI, 1.02-4.02]; =0.044). In addition to AAA diameter, pDES provided incremental improvement in risk stratification (continuous net reclassification improvement, 34.4% [95% CI, -10.8% to 57.5%; =0.09]; integrated discrimination improvement, 0.04 [95% CI, 0.00-0.15; =0.050]). Conclusions pDES concentrations predict disease severity and clinical outcomes in patients with AAA. Clinical Trial Registration http://www.isrctn.com. Unique identifier: ISRCTN76413758.
Topics: Aged; Aorta, Abdominal; Aortic Aneurysm, Abdominal; Biomarkers; Cardiac Catheterization; Desmosine; Female; Follow-Up Studies; Humans; Incidence; Male; Prognosis; Prospective Studies; Survival Rate; Ultrasonography; United Kingdom
PubMed: 31595818
DOI: 10.1161/JAHA.119.013743 -
Experimental Cell Research Nov 2019Abdominal aortic aneurysms (AAA) are characterized by matrix remodeling, elastin degradation, absence of nitric oxide (NO) signaling, and inflammation, influencing...
Abdominal aortic aneurysms (AAA) are characterized by matrix remodeling, elastin degradation, absence of nitric oxide (NO) signaling, and inflammation, influencing smooth muscle cell (SMC) phenotype and gene expression. Little is known about the biomolecular release and intrinsic biomechanics of human AAA-SMCs. NO delivery could be an attractive therapeutic strategy to restore lost functionality of AAA-SMCs by inhibiting inflammation and cell stiffening. We aim to establish the differences in phenotype and gene expression of adult human AAA-SMCs from healthy SMCs. Based on our previous study which showed benefits of optimal NO dosage delivered via S-Nitrosoglutathione (GSNO) to healthy aortic SMCs, we tested whether such benefits would occur in AAA-SMCs. The mRNA expression of three genes involved in matrix degradation (ACE, ADAMTS5 and ADAMTS8) was significantly downregulated in AAA-SMCs. Total protein and glycosaminoglycans synthesis were higher in AAA-SMCs than healthy-SMCs (p < 0.05 for AAA-vs. healthy- SMC cultures) and was enhanced by GSNO and 3D cultures (p < 0.05 for 3D vs. 2D cultures; p < 0.05 for GSNO vs. non-GSNO cases). Elastin gene expression, synthesis and deposition, desmosine crosslinker levels, and lysyl oxidase (LOX) functional activity were lower, while cell proliferation, iNOS, LOX and fibrillin-1 gene expressions were higher in AAA-SMCs (p < 0.05 between respective cases), with differential benefits from GSNO exposure. GSNO and 3D cultures reduced MMPs -2, -9, and increased TIMP-1 release in AAA-SMC cultures (p < 0.05 for GSNO vs. non-GSNO cultures). AAA-SMCs were inherently stiffer and had smoother surface than healthy SMCs (p < 0.01 in both cases), but GSNO reduced stiffness (~25%; p < 0.01) and increased roughness (p < 0.05) of both cell types. In conclusion, exogenously-delivered NO offers an attractive strategy by providing therapeutic benefits to AAA-SMCs.
Topics: Adult; Aged; Aorta; Aortic Aneurysm, Abdominal; Case-Control Studies; Cell Proliferation; Cells, Cultured; Extracellular Matrix; Gene Expression; Humans; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Nitric Oxide; Nitric Oxide Synthase Type II; Phenotype; Tissue Inhibitor of Metalloproteinase-1
PubMed: 31473210
DOI: 10.1016/j.yexcr.2019.111589 -
Journal of Clinical Medicine Jul 2019Elastin degradation is accelerated in chronic obstructive pulmonary disease (COPD) and is partially regulated by Matrix Gla Protein (MGP), via a vitamin K-dependent...
Elastin degradation is accelerated in chronic obstructive pulmonary disease (COPD) and is partially regulated by Matrix Gla Protein (MGP), via a vitamin K-dependent pathway. The aim was to assess vitamin K status in COPD as well as associations between vitamin K status, elastin degradation, lung function parameters and mortality. A total of 192 COPD patients and 186 age-matched controls were included. In addition to this, 290 COPD patients from a second independent longitudinal cohort were also included. Vitamin K status was assessed by measuring plasma inactive MGP levels and rates of elastin degradation by measuring plasma desmosine levels. Reduced vitamin K status was found in COPD patients compared to smoking controls ( < 0.0005) and controls who had never smoked ( = 0.001). Vitamin K status was inversely associated with desmosine (cohort 1: = 0.001; cohort 2: = 0.004). Only few significant associations between vitamin K status and lung function parameters were found. Mortality was higher in COPD patients within the quartile with the lowest vitamin K status compared to those within the other quartiles (hazard ratio 1.85, 95% confidence interval (CI), 1.21-2.83, = 0.005). In conclusion, we demonstrated reduced vitamin K status in COPD and an inverse association between vitamin K status and elastin degradation rate. Our results therefore suggest a potential role of vitamin K in COPD pathogenesis.
PubMed: 31357639
DOI: 10.3390/jcm8081116 -
Biomechanics and Modeling in... Feb 2020Deposition of elastin and collagen in the aorta correlates with increases in blood pressure and flow during development, suggesting that the aorta adjusts its mechanical...
Deposition of elastin and collagen in the aorta correlates with increases in blood pressure and flow during development, suggesting that the aorta adjusts its mechanical properties in response to hemodynamic stresses. Elastin knockout (Eln) mice have high blood pressure and pathological remodeling of the aorta and die soon after birth. We hypothesized that decreasing blood pressure in Eln mice during development may reduce hemodynamic stresses and alleviate pathological remodeling of the aorta. We treated Eln and Eln mice with the anti-hypertensive medication captopril throughout embryonic development and then evaluated left ventricular (LV) pressure and aortic remodeling at birth. We found that captopril treatment decreased Eln LV pressure to values near Eln mice and alleviated the wall thickening and changes in mechanical behavior observed in untreated Eln aorta. The changes in thickness and mechanical behavior in captopril-treated Eln aorta were not due to alterations in measured elastin or collagen amounts, but may have been caused by alterations in smooth muscle cell (SMC) properties. We used a constitutive model to understand how changes in stress contributions of each wall component could explain the observed changes in composite mechanical behavior. Our modeling results show that alterations in the collagen natural configuration and SMC properties in the absence of elastin may explain untreated Eln aortic behavior and that partial rescue of the SMC properties may account for captopril-treated Eln aortic behavior.
Topics: Animals; Animals, Newborn; Aorta; Biomechanical Phenomena; Blood Pressure; Captopril; Desmosine; Elastin; Extracellular Matrix Proteins; Gene Expression Regulation; Heart Rate; Heart Ventricles; Hydroxyproline; Mice, Knockout; Myocytes, Smooth Muscle; RNA, Messenger; Receptors, Angiotensin; Stress, Mechanical; Vascular Remodeling
PubMed: 31270728
DOI: 10.1007/s10237-019-01198-2 -
The FEBS Journal Sep 2019Elastin is an essential structural protein in the extracellular matrix of vertebrates. It is the core component of elastic fibers, which enable connective tissues such...
Elastin is an essential structural protein in the extracellular matrix of vertebrates. It is the core component of elastic fibers, which enable connective tissues such as those of the skin, lungs or blood vessels to stretch and recoil. This function is provided by elastin's exceptional properties, which mainly derive from a unique covalent cross-linking between hydrophilic lysine-rich motifs of units of the monomeric precursor tropoelastin. To date, elastin's cross-linking is poorly investigated. Here, we purified elastin from human tissue and cleaved it into soluble peptides using proteases with different specificities. We then analyzed elastin's molecular structure by identifying unmodified residues, post-translational modifications and cross-linked peptides by high-resolution mass spectrometry and amino acid analysis. The data revealed the presence of multiple isoforms in parallel and a complex and heterogeneous molecular interconnection. We discovered that the same lysine residues in different monomers were simultaneously involved in various cross-link types or remained unmodified. Furthermore, both types of cross-linking domains, Lys-Pro and Lys-Ala domains, participate not only in bifunctional inter- but also in intra-domain cross-links. We elucidated the sequences of several desmosine-containing peptides and the contribution of distinct domains such as 6, 14 and 25. In contrast to earlier assumptions proposing that desmosine cross-links are formed solely between two domains, we elucidated the structure of a peptide that proves a desmosine formation with participation of three Lys-Ala domains. In summary, these results provide new and detailed insights into the cross-linking process, which takes place within and between human tropoelastin units in a stochastic manner.
Topics: Amino Acid Sequence; Desmosine; Elastic Tissue; Elastin; Extracellular Matrix; Humans; Hydrophobic and Hydrophilic Interactions; Lysine; Mass Spectrometry; Molecular Structure; Peptides; Protein Isoforms; Protein Processing, Post-Translational; Skin; Tropoelastin
PubMed: 31102572
DOI: 10.1111/febs.14929