-
Analytical and Bioanalytical Chemistry Oct 2018Desmosine (Des) and isodesmosine (Isodes), cross-linking amino acids in the biomolecule elastin, may be used as biomarkers for various pathological conditions associated...
Desmosine (Des) and isodesmosine (Isodes), cross-linking amino acids in the biomolecule elastin, may be used as biomarkers for various pathological conditions associated with elastin degradation. The current study presents a novel approach to quantify Des and Isodes using matrix-assisted laser desorption ionization (MALDI)-tandem mass spectrometry (MS) in a linear ion trap coupled to a vacuum MALDI source. MALDI-MS analyses of Des and Isodes are performed using stable-isotope-labeled desmosine d (labeled-Des) as an internal standard in different biological fluids, such as urine and serum. The method demonstrated linearity over two orders of magnitude with a detection limit of 0.02 ng/μL in both urine and serum without enrichment prior to mass spectrometry, and relative standard deviation of < 5%. The method is used to evaluate the time-dependent degradation of Des upon UV irradiation (254 nm) and found to be consistent with quantification by H NMR. This is the first characterized MALDI-MS method for quantification of Des and Isodes and illustrates the potential of MALDI-ion trap MS for effective quantification of biomolecules. The reported method represents improvement over current liquid chromatography-based methods with respect to analysis time and solvent consumption, while maintaining similar analytical characteristics. Graphical abstract ᅟ.
Topics: Desmosine; Humans; Limit of Detection; Reference Standards; Reproducibility of Results; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Tandem Mass Spectrometry
PubMed: 30062515
DOI: 10.1007/s00216-018-1288-z -
Respiratory Research Mar 2018Although chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) seem to be opposite entities from a clinical perspective, common initial...
Although chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) seem to be opposite entities from a clinical perspective, common initial pathogenic steps have been suggested in both lung diseases. Emphysema is caused by an elastase/anti-elastase imbalance leading to accelerated elastin degradation. Elastinolysis is however, also accelerated in the IPF patients' lungs. The amino acids desmosine and isodesmosine (DES) are unique to elastin. During the degradation process, elastases liberate DES from elastin fibers. Blood DES levels consequently reflect the rate of systemic elastinolysis and are increased in COPD. This is the first report describing elevated DES levels in IPF patients. We also demonstrated that the age-related increment of DES concentrations is enhanced in IPF. Our current study suggests that elastinolysis is a shared pathogenic step in both COPD and IPF. Further investigation is required to establish the relevance of accelerated elastin degradation in IPF and to determine whether decelerating this process leads to slower progression of lung fibrosis and better survival for patients with IPF.
Topics: Aged; Aging; Biomarkers; Desmosine; Elastin; Female; Humans; Idiopathic Pulmonary Fibrosis; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive
PubMed: 29558926
DOI: 10.1186/s12931-018-0747-6 -
Respiratory Research Jan 2018There are urgent needs for clinically relevant biomarkers to identify children with cystic fibrosis (CF) at risk for more progressive lung disease and to serve as...
BACKGROUND
There are urgent needs for clinically relevant biomarkers to identify children with cystic fibrosis (CF) at risk for more progressive lung disease and to serve as outcome measures for clinical trials. Our objective was to investigate three targeted biomarkers in a population of asymptomatic CF infants.
METHODS
Urine, blood and lung function data were collected for 2 years from clinically stable infants diagnosed with CF by newborn screening. A subset of CF infants had bronchoscopy with lavage performed at 6 months and 1 year. Urine was collected quarterly from healthy control infants. Expectorated sputum and urine were collected quarterly for 2 years from clinically stable CF adults. Desmosine, club cell secretory protein (CCSP) and cathepsin B concentrations were measured and compared. Mixed effects models were used to identify associations between biomarker concentrations and clinical characteristics. Receiver operator characteristic curves were generated to investigate the sensitivity and specificity of the biomarkers.
RESULTS
Urinary cathepsin B was significantly higher in CF infants compared to healthy infants (p = 0.005). CF infant airway and urinary cathepsin B concentrations were significantly lower compared to adult CF subjects (p = 0.002 & p = 0.022, respectively). CF infant airway CCSP was significantly higher than adult CF subjects (p < 0.001). There was a significant correlation between CF infant plasma CCSP and BALF CCSP (p = 0.046). BALF CCSP was negatively associated with IL-8 (p = 0.017). There was no correlation between biomarker concentration and FEV.
CONCLUSIONS
Cathepsin B and CCSP show promise as biomarkers of inflammation in CF infants. Further study is needed.
Topics: Biomarkers; Bronchoalveolar Lavage Fluid; Child, Preschool; Cohort Studies; Cystic Fibrosis; Female; Humans; Infant; Infant, Newborn; Inflammation; Longitudinal Studies; Male; Neonatal Screening; Neutrophils; Prospective Studies; Sputum
PubMed: 29310632
DOI: 10.1186/s12931-017-0713-8 -
Respiratory Research Dec 2017The role of neutrophil elastase (NE) is poorly understood in bronchiectasis because of the lack of preclinical data and so most of the assumptions made about NE... (Review)
Review
The role of neutrophil elastase (NE) is poorly understood in bronchiectasis because of the lack of preclinical data and so most of the assumptions made about NE inhibitor potential benefit is based on data from CF. In this context, NE seems to be a predictor of long-term clinical outcomes and a possible target of treatment. In order to better evaluate the role of NE in bronchiectasis, a systematic search of scientific evidence was performed.Two investigators independently performed the search on PubMed and included studies published up to May 15, 2017 according to predefined criteria. A final pool of 31 studies was included in the systematic review, with a total of 2679 patients. For each paper data of interest were extracted and reported in table.In this review sputum NE has proved useful as an inflammatory marker both in stable state bronchiectasis and during exacerbations and local or systemic antibiotic treatment. NE has also been associated with risk of exacerbation, time to next exacerbation and all-cause mortality. This study reviews also the role of NE as a specific target of treatment in bronchiectasis. Inhibition of NE is at a very early stage and future interventional studies should evaluate safety and efficacy for new molecules and formulations.
Topics: Biomarkers; Bronchiectasis; Cross-Sectional Studies; Humans; Leukocyte Elastase; Sputum
PubMed: 29258516
DOI: 10.1186/s12931-017-0691-x -
Respiratory Research Nov 2017Cardiovascular diseases are prevalent in patients with chronic obstructive pulmonary disease (COPD). Their coexistence implies that many COPD patients require... (Review)
Review
Cardiovascular diseases are prevalent in patients with chronic obstructive pulmonary disease (COPD). Their coexistence implies that many COPD patients require anticoagulation therapy. Although more and more replaced by direct oral anticoagulants, vitamin K antagonists (VKAs) are still widely used. VKAs induce profound deficiency of vitamin K, a key activator in the coagulation pathway. It is recognized however that vitamin K is also an essential cofactor in the activation of other extrahepatic proteins, such as matrix Gla protein (MGP), a potent inhibitor of arterial calcification. No or insufficient MGP activation by the use of VKAs is associated with a rapid progression of vascular calcification, which may enhance the risk for overt cardiovascular disease. Vitamin K consumption, on the other hand, seems to have a protective effect on the mineralization of arteries. Furthermore, vascular calcification mutually relates to elastin degradation, which is accelerated in patients with COPD associating with impaired survival. In this commentary, we hypothesize that vitamin K is a critical determinant to the rate of elastin degradation. We speculate on the potential link between poor vitamin K status and crucial mechanisms of COPD pathogenesis and raise concerns about the use of VKAs in patients with this disease. Future intervention studies are needed to explore if vitamin K supplementation is able to reduce elastin degradation and vascular calcification in COPD patients.
Topics: Animals; Cardiovascular Diseases; Dietary Supplements; Humans; Pulmonary Disease, Chronic Obstructive; Vascular Calcification; Vitamin K; Vitamin K Deficiency
PubMed: 29132356
DOI: 10.1186/s12931-017-0673-z -
International Journal of Chronic... 2017A novel therapy for COPD involving the use of aerosolized hyaluronan (HA) was tested on a small cohort of COPD patients to determine both its safety and efficacy in... (Randomized Controlled Trial)
Randomized Controlled Trial
A novel therapy for COPD involving the use of aerosolized hyaluronan (HA) was tested on a small cohort of COPD patients to determine both its safety and efficacy in reducing levels of desmosine and isodesmosine (DID), biomarkers for elastin degradation. In a 2-week, randomized, double-blind trial, 8 patients receiving 150 kDa HA (mean molecular weight) and 3 others given placebo did not show significant adverse effects with regard to spirometry, electrocardiograms, and hematological indices. Furthermore, measurements of DID in plasma from HA-treated patients indicated a progressive decrease over a 3-week period following initiation of treatment (=-0.98; =0.02), whereas patients receiving placebo showed no reduction in DID (=-0.70; =0.30). Measurements of sputum in the HA-treated group also revealed a progressive decrease in DID (=-0.97; =0.03), but this finding was limited by the absence of similar measurements in the placebo group. Nevertheless, the results of this small, pilot study support a longer-term trial of HA in a larger population of COPD patients.
Topics: Administration, Inhalation; Adult; Aerosols; Aged; Arizona; Biomarkers; Desmosine; Double-Blind Method; Elastin; Humans; Hyaluronic Acid; Isodesmosine; Lung; Middle Aged; New York City; Pilot Projects; Pulmonary Disease, Chronic Obstructive; Sputum; Time Factors; Treatment Outcome
PubMed: 29075107
DOI: 10.2147/COPD.S142156 -
Medical Hypotheses Oct 2017Elastin is a unique protein providing deformability and resilience to dynamic tissues, such as arteries and lungs. It is an absolute basic requirement for circulation...
Elastin is a unique protein providing deformability and resilience to dynamic tissues, such as arteries and lungs. It is an absolute basic requirement for circulation and respiration. Elastin can be degraded by elastases and has a high calcium affinity. Elastin calcification and elastin degradation are two pathological processes that impair elastin's functioning. Furthermore, elastin degradation can be associated to elastin calcification. Matrix Gla Protein (MGP) is probably the most potent natural inhibitor of elastin calcification and requires vitamin K for its activation. Measuring circulating levels of inactive MGP (dp-ucMGP) is a frequently used method to assess vitamin K status. Dp-ucMGP reflects the burden of vitamin K-dependent proteins that have not been activated by vitamin K and could therefore best be regarded as a biomarker of a vitamin K deficit. Dp-ucMGP levels decrease after vitamin K supplementation. Since the amino acids desmosine and isodesmosine (DES) are unique to crosslinked elastin fibers, systemic elastin degradation can be assessed with the plasma DES assay. Recently, we discovered a strong correlation between plasma dp-ucMGP and plasma DES levels in both patients with chronic obstructive pulmonary disease (COPD) and controls. The 'Vitamin K deficit and elastolysis theory' posits that elastin degradation causes a rise in the vitamin K deficit and implies that vitamin K supplementation could be preventing elastin degradation. If this hypothesis holds true and is universally found in every state and condition, it will have an unprecedented impact on the management of every single pulmonary disease characterized by accelerated elastin degradation, such as alpha-1 antitrypsin deficiency, bronchiectasis, COPD and cystic fibrosis. Theoretically, a plasma dp-ucMGP concentration of zero would be associated with a near-complete standstill of elastin degradation and disease progression in patients with any of these debilitating conditions.
Topics: Biomarkers; Calcium; Calcium-Binding Proteins; Desmosine; Elasticity; Elastin; Extracellular Matrix Proteins; Humans; Isodesmosine; Lung Diseases; Models, Biological; Vitamin K; Vitamin K Deficiency; alpha 1-Antitrypsin; Matrix Gla Protein
PubMed: 29055397
DOI: 10.1016/j.mehy.2017.07.029 -
Biochemistry and Biophysics Reports Jul 2017Elastic fibers, a major component of the extracellular matrix of the skin, are often exposed to ultraviolet (UV) radiation throughout mammalian life. We report on an...
Elastic fibers, a major component of the extracellular matrix of the skin, are often exposed to ultraviolet (UV) radiation throughout mammalian life. We report on an study of the alterations in bovine nuchal ligament elastic fibers resulting from continuous UV-A exposure by the use of transmission electron microscopy (TEM), histology, mass spectrometry, and solid state C NMR methodologies. TEM images reveal distinct cracks in elastic fibers as a result of UV-A irradiation and histological measurements show a disruption in the regular array of elastic fibers present in unirradiated samples; elastic fibers appear shorter, highly fragmented, and thinner after UV-A treatment. Magic angle spinning C NMR was applied to investigate possible secondary structural changes or dynamics in the irradiated samples; our spectra reveal no differences between UV-A irradiated and non-irradiated samples. Lastly, MALDI mass spectrometry indicates that the concentration of desmosine, which forms cross-links in elastin, is observed to decrease by 11 [Formula: see text] following 9 days of continuous UV-A irradiation, in comparison to unirradiated samples. These alterations presumably play a significant role in the loss of elasticity observed in UV exposed skin.
PubMed: 28955744
DOI: 10.1016/j.bbrep.2017.04.002 -
Scientific Reports Aug 2017Tendon is composed of fascicles bound together by the interfascicular matrix (IFM). Energy storing tendons are more elastic and extensible than positional tendons;...
Tendon is composed of fascicles bound together by the interfascicular matrix (IFM). Energy storing tendons are more elastic and extensible than positional tendons; behaviour provided by specialisation of the IFM to enable repeated interfascicular sliding and recoil. With ageing, the IFM becomes stiffer and less fatigue resistant, potentially explaining why older tendons become more injury-prone. Recent data indicates enrichment of elastin within the IFM, but this has yet to be quantified. We hypothesised that elastin is more prevalent in energy storing than positional tendons, and is mainly localised to the IFM. Further, we hypothesised that elastin becomes disorganised and fragmented, and decreases in amount with ageing, especially in energy storing tendons. Biochemical analyses and immunohistochemical techniques were used to determine elastin content and organisation, in young and old equine energy storing and positional tendons. Supporting the hypothesis, elastin localises to the IFM of energy storing tendons, reducing in quantity and becoming more disorganised with ageing. These changes may contribute to the increased injury risk in aged energy storing tendons. Full understanding of the processes leading to loss of elastin and its disorganisation with ageing may aid in the development of treatments to prevent age related tendinopathy.
Topics: Aging; Animals; Desmosine; Elastin; Extracellular Matrix; Fascia; Fluorescent Antibody Technique; Horses; Tendinopathy; Tendons
PubMed: 28855560
DOI: 10.1038/s41598-017-09995-4 -
Chronic Obstructive Pulmonary Diseases... Nov 2016The RAPID (NCT00261833; N=180) and RAPID Extension (NCT00670007; N=140) trials demonstrated significantly reduced lung density decline in patients with alpha-1...
The RAPID (NCT00261833; N=180) and RAPID Extension (NCT00670007; N=140) trials demonstrated significantly reduced lung density decline in patients with alpha-1 antitrypsin deficiency (AATD) receiving alpha-1 proteinase inhibitor (A1PI) versus placebo. Desmosine and isodesmosine (DES/IDES) are unique crosslinkers of mature elastin fibers and are utilized as measures of elastin degradation. The aim of this post-hoc study was to determine the effect of A1PI therapy on DES/IDES levels in patients from RAPID/RAPID Extension. Plasma levels of DES/IDES were measured using high-performance liquid chromatography and tandem mass spectrometry. Correlation between changes in DES/IDES levels and computed tomography (CT) lung density decline was assessed. Analysis showed that DES/IDES levels were significantly reduced versus baseline in patients receiving A1PI at all time points, from month 3 through month 48. A significant increase from baseline in DES/IDES was observed with placebo at month 24 (n=54; 0.016; =0.018). DES/IDES change from baseline was significantly different with A1PI versus placebo at months 3 (-0.021; 95% confidence interval [CI] -0.037, 0.004; =0.026), 12 (-0.040; 95% CI -0.055, 0.025; <0.001), and 24 (-0.052; 95% CI -0.070, 0.034; <0.001). Placebo patients started A1PI therapy at month 24 and showed significant reductions in plasma DES/IDES at months 36 (<0.001) and 48 (<0.001). Reduced elastin degradation was associated with slower lung density decline (=0.005), correlating a chemical index of therapy with an anatomical index by CT. In conclusion, A1PI therapy reduced elastin degradation, including pulmonary elastin, in patients with AATD. These data support using DES/IDES levels as biomarkers to monitor emphysema progression and treatment response.
PubMed: 28848909
DOI: 10.15326/jcopdf.4.1.2016.0156