elastin and pyridinoline

Liver fibrosis is a serious complication of schistosomiasis infection, is associated with increased amounts of collagen and the collagen cross-link, pyridinoline. Non-invasive markers of liver fibrosis have been developed. Serum and urinary markers of collagen synthesis and degradation have been studied to assess the balance between collagen synthesis, measured with markers of collagen synthesis such as amino-terminal propeptide of type III procollagen (PIIINP), and markers of degradation such as pyridinoline or pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP). It has been shown that mice infected with Schistosomiasis mansoni excrete excess pyridinoline cross links in urine and this was correlated with the collagen content of granulomas from the liver. Treatment of infected mice with an anti-parasitic drug, praziquantel, decreased the collagen content of parenchyma and excretion of pyridinoline in the urine. Although the connective tissue protein, elastin, is present in the liver, the role of elastin in liver fibrosis has not been investigated. However, it has been shown that the urinary concentration of elastin specific crosslinks, desmosine and isodesmosine, as well as the urinary concentration of the collagen crosslink, pyridinoline, correlated well with liver fibrosis score in biopsy specimens from patients with liver disease secondary to hepatitis C virus and alcohol. Each biopsy specimen was reviewed by two pathologists who were blinded as to the clinical data. The pathological evaluation generated scores for both inflammation and fibrosis. No correlation was seen between the urinary markers and inflammation scores. The measurement of non-invasive markers of collagen synthesis and degradation may be useful in monitoring the reversal of fibrosis following therapeutic intervention in schistosome infections.

Topics: Amino Acids; Animals; Biomarkers; Collagen; Desmosine; Elastin; Humans; Isodesmosine; Liver Cirrhosis; Schistosomiasis

Topics: Aging; Amino Acids; Animals; Bone and Bones; Borohydrides; Buffers; Cartilage; Chemical Fractionation; Chemical Phenomena; Chemistry; Chromatography; Collagen; Cyanides; Drug Stability; Elastin; Glycosides; Hexoses; Hydrogen-Ion Concentration; Hydrolysis; Hydroxylysine; Lysine; Mass Spectrometry; Oxidation-Reduction; Periodic Acid; Schiff Bases; Skin

We assessed the effects of D-penicillamine (D-PA) on cross-linkages in elastin and vaso-regulatory function in rats. After administration of D-PA at a dose of 100 mg/kg/day for 7 weeks to adult and young rats, the thoracic aortas were isolated. The elastic lamellae in the aorta were disrupted histopathologically in all the treated groups. The content of cross-linkages in elastin, i.e. desmosine and isodesmosine, which gives elasticity to the aortic wall, was significantly reduced in the D-PA treated groups versus the control groups. On the other hand, the content of pyridinoline as a marker of insoluble collagen was significantly reduced in the D-PA treated groups, even though the total collagen content was not changed. In addition, after 7 weeks of treatment with D-PA, the change between systolic blood pressure before and after sympathetic stimulation (Δ-SBP) by L-epinephrine was about 2.5-fold larger than that in the control group. Similar results were obtained using angiotensin II or ouabain instead of L-epinephrine. These findings demonstrated that D-PA disrupted elastic lamellae of the rat aorta by reduction of the cross-linkages in elastin and collagen, which caused dysfunction of vaso-regulation. Also, they suggested the possibility that long-term treatment with D-PA in patients could cause a decrease in vaso-regulatory function and could increase the risk of cardiovascular events.

Topics: Administration, Oral; Age Factors; Amino Acids; Animals; Aorta; Arterial Pressure; Cardiovascular Diseases; Chelating Agents; Desmosine; Elastic Tissue; Elasticity; Elastin; Humans; Injections, Subcutaneous; Isodesmosine; Male; Penicillamine; Rats; Rats, Sprague-Dawley

We assessed the effects of rofecoxib on cross-linkage formation in elastin and vaso-regulatory function in rats. After administration of rofecoxib at a dose of 10 mg/kg for 7 weeks to young rats and for 7 and 10 weeks to adult rats, thoracic aortas were isolated. The elastic lamellae in the aortas were disrupted histopathologically in all the treated groups. However, the content of cross-linkages in elastin, i.e. desmosine and isodesmosine, which give elasticity to the aortic wall, was not significantly different between the rofecoxib treated and control groups. On the other hand, although the baseline blood pressure was not changed during the treatment period in both young and adult rats, after several weeks of treatment with rofecoxib the change between systolic blood pressure before and after sympathetic stimulation by L-epinephrine was 2 to 3-fold larger than that in the control group. Similar results were obtained using angiotensin II instead of L-epinephrine. The exposure to rofecoxib (area under the plasma concentration-time curve) of rats after single administration was a few times higher than that of humans in clinical use. These findings indicate that rofecoxib did not directly inhibit formation of cross-linkages in elastin of the aorta in rats. However, the treatment with rofecoxib for several weeks disrupted elastic lamellae and caused depression of vaso-regulatory function in rats, which could bring on an increased risk of cardiovascular events in human.

Topics: Administration, Oral; Age Factors; Amino Acids; Animals; Aorta; Arterial Pressure; Cardiovascular Diseases; Cyclooxygenase 2 Inhibitors; Desmosine; Elastic Tissue; Elasticity; Elastin; Humans; Injections, Subcutaneous; Isodesmosine; Lactones; Male; Rats; Rats, Sprague-Dawley; Sulfones

A key challenge in tissue engineering a heart valve is to reproduce the major tissue structures responsible for native valve function. Here we evaluated human adipose-derived stem cells (ADSCs) as a source of cells for heart valve tissue engineering investigating their ability to synthesize and process collagen and elastin. ADSCs were compared with human bone marrow mesenchymal stem cells (BmMSCs) and human aortic valve interstitial cells (hVICs). ADSCs and BmMSCs were stretched at 14% for 3 days and collagen synthesis determined by [(3)H]-proline incorporation. Collagen and elastin crosslinking was assessed by measuring pyridinoline and desmosine respectively, using liquid chromatography/mass spectrometry. Three-dimensional culture was obtained by seeding cells onto bovine collagen type I scaffolds for 2-20 days. Expression of matrix proteins and processing enzymes was assessed by Real Time-PCR, immunofluorescence and transmission electron microscopy. Stretch increased the incorporation of [(3)H]-proline in ADSCs and BmMSCs, however only ADSCs and hVICs upregulated COL3A1 gene. ADSCs produced collagen and elastin crosslinks. ADSCs uniformly populated collagen scaffolds after 2 days, and fibrillar-like collagen was detected after 20 days. ADSCs sense mechanical stimulation and produce and process collagen and elastin. These novel findings have important implications for the use of these cells in tissue engineering.

Topics: Adipose Tissue; Adult; Amino Acids; Cell Shape; Collagen; Cross-Linking Reagents; Desmosine; Elastin; Extracellular Matrix; Gene Expression Regulation; Heart Valve Prosthesis; Humans; Mesenchymal Stem Cells; Middle Aged; Phenotype; Proline; Stem Cells; Stress, Mechanical; Tissue Engineering; Tissue Scaffolds

The aim of this study is to develop a standardized LC-MS/MS method for accurate measurement of desmosine (DES) and isodesmosine (IDS) in all body fluids as biomarkers for in vivo degradation of matrix tissue elastin in man and animals. A reproducible three-step analytical procedure: (1) sample hydrolysis in 6N HCl, (2) SPE by a CF1 cartridge with addition of acetylated pyridinoline as internal standard (IS), and (3) LC/MSMS analysis by SRM monitoring of transition ions; DES or IDS (m/z 526-481+397) and IS (m/z 471-128) was developed. The method achieves accurate measurements of DES/IDS in accessible body fluids (i.e. urine, plasma, and sputum). LOQ of DES/IDS in body fluids is 0.1 ng/ml. The % recoveries and reproducibility from urine, plasma, and sputum samples are above 99 ± 8% (n = 3), 94 ± 9% (n = 3) and 87 ± 11% (n = 3), with imprecision 8%, 9% and 10%, respectively. The proposed method was applied to measure DES/IDS in body fluids of patients with chronic obstructive pulmonary disease (COPD) and healthy controls. Total DES/IDS in sputum and plasma is increased over normal controls along with the free DES/IDS in urine in patients. DES/IDS can be used to study the course of COPD and the response to therapy. This practical and reliable LC-MS/MS method is proposed as a standardized method to measure DES and IDS in body fluids. This method can have wide application for investigating diseases which involve elastic tissue degradation.

Topics: Amino Acids; Biomarkers; Case-Control Studies; Chromatography, Liquid; Desmosine; Elastin; Humans; Hydrochloric Acid; Hydrolysis; Isodesmosine; Pulmonary Disease, Chronic Obstructive; Reproducibility of Results; Sensitivity and Specificity; Sputum; Tandem Mass Spectrometry

Among tissue grafts used for reconstruction of the anterior cruciate ligament (ACL), the pateller tendon (PT) and semitendinosus tendon (ST) are commonly used. It was thought that there were differences in the biochemical composition and process of healing between PT and ST. The aim of this study was to investigate the biochemical difference between ACL and the graft tissues used for reconstruction of the ACL. Hydroxyproline and crosslinks of collagen and elastin were measured from samples of 29 knees from cadavers preserved in formalin solutions. The results of measurements were hydroxyproline: ACL 0.522, PT 0.577, ST 0.463 (micromol/mg dry weight); pyridinoline/collagen: ACL 0.381, PT 0.272, ST 0.244 (mol/mol); and pentosidine/collagen: ACL 0.0434, PT 0.0558, ST 0.0799 (mol/mol). The biochemical properties of PT was not so different from ST. Pentosidine also was measured in the present study to aid in the comparison of the ligament and tendons of the knee joint.

Topics: Age Factors; Amino Acids; Anterior Cruciate Ligament; Arginine; Chromatography, High Pressure Liquid; Collagen; Elastin; Humans; Hydroxyproline; Lysine; Patellar Ligament

Mice with lung-specific expression of human matrix metalloproteinase-1 (MMP-1) develop emphysematous changes similar to those seen in smoking-induced emphysema in humans. Morphometric analyses of three transgenic lines [homozygous colony (Col) 34, Col 50, and Col 64] with varying temporal expression of MMP-1 were undertaken to determine the validity of this animal as a model of adult-onset emphysema. Line 50 mice, which have early expression of MMP-1 (14 days postconception), exhibited morphometric changes by 5 days of age. In contrast, homozygous line 34 and 64 with delayed expression (birth and 2 wk of age) were normal up until 4 wk of age when progressive changes in their mean linear intercept were first noted. In contrast, heterozygous mice from line 34 with lower transgene expression did not develop emphysema until 1 yr of age. The changes in mean linear intercept coincided with an increase in lung compliance. Emphysema in these mice was associated with decreased immunostaining for type III collagen within the alveolar septa. This study provides evidence that MMP-1 induces progressive adult-onset emphysema by the selective degradation of type III collagen within the alveolar wall.

Topics: Acute Disease; Age of Onset; Amino Acids; Animals; Bronchoalveolar Lavage Fluid; Collagen Type I; Collagen Type III; Elastin; Emphysema; Extracellular Matrix; Gene Expression Regulation, Enzymologic; Humans; Hydroxyproline; Immunohistochemistry; Leukocyte Count; Lung; Lung Compliance; Matrix Metalloproteinase 1; Mice; Mice, Inbred C57BL; Mice, Inbred CBA; Mice, Transgenic; Transgenes

The aim of this study was to detect crosslinks of collagen and elastin in formalin-fixed tissue, to perform quantification of these crosslinks, and to investigate the effects of formalin fixation on crosslink contents in human yellow ligament and cartilage. Pyridinoline (Pyr) is a stable and nonreducible crosslink of collagen. Pentosidine (Pen) is a senescent crosslink formed between arginine and lysine in matrix proteins, including collagen. Desmosine (Des) and its isomer isodesmosine (Isodes) are crosslinks specifically found in elastin. It is useful to measure crosslink contents of collagen and elastin as a way of investigating the properties of various tissues or their pathological changes. If it is possible to evaluate crosslinks of collagen and elastin in formalin-fixed tissues, we can investigate crosslinks in a wide variety of tissues. We used HPLC to compare the concentrations of Pyr, Pen, Des, and Isodes in the formalin-fixed tissues with their concentrations in the frozen tissues. Pyr and Pen were detected in both the formalin-fixed yellow ligament and the cartilage, and their concentrations were not significantly affected by or related to the duration of formalin fixation. Des and Isodes were detected in the formalin-fixed yellow ligament but in significantly lower amounts compared to the frozen samples. We concluded that crosslinks of collagen were preserved in formalin, but crosslinks of elastin were not preserved in it. The reason for this might be that formalin did not fix elastin tissues sufficiently or it destroyed, masked, or altered elastin crosslinks.

Topics: Aged; Aged, 80 and over; Amino Acids; Arginine; Cartilage; Chromatography, High Pressure Liquid; Collagen; Cross-Linking Reagents; Desmosine; Elastin; Formaldehyde; Freezing; Hip Joint; Humans; Isodesmosine; Ligaments; Lysine; Tissue Fixation

In an attempt to identify potential staging markers of effective healing, changes in connective tissue properties were measured in a human skin excisional wound healing model in which tissue was re-excised at intervals up to 6 months after injury. The proportion of collagen III relative to collagen I increased significantly (p<0.001) up to 6 weeks after initial injury and remained elevated up to 6 months, at which time the proportion of collagen III was 70% above baseline values. Extractability of biopsy tissue collagen by pepsin increased significantly throughout the study (baseline, 32.8+/-6.8%; 6 months, 89.1+/-8.9%), with inverse changes in the mature skin cross-link, histidinohydroxylysinonorleucine (baseline, 1.18+/-0.11 mol/mol collagen; 6 months, 0.27+/-0.09 mol/mol collagen). Pyridinoline content increased over the period of the study, although remaining at relatively low concentrations (baseline, 0.037+/-0.011; 6 months, 0.063+/-0.014 mol/mol collagen), and the pyridinoline/deoxypyridinoline ratio was significantly higher (baseline, 3.5+/-0.6; 6 months, 10.3+/-2.2). Elastin content, measured as desmosine cross-links, decreased significantly in the first 3 weeks and continued to decline over the period of study. Overall, the data suggest that remodeling of the wound tissue continues at least up to 6 months after injury. The close inverse correlation between histidinohydroxylysinonorleucine concentrations and extractability by pepsin (r2=0.89, p<0.0001) suggests a causal relationship, consistent with the likely effects of a substantial network of mature, inter-helical bonds in collagen.

Topics: Adult; Amino Acids; Collagen; Collagen Type I; Collagen Type III; Dipeptides; Elastin; Histidine; Humans; Male; Skin; Time Factors; Wound Healing; Wounds, Penetrating

The cranial skeleton of the lamprey, a primitive vertebrate, consists of cartilaginous structures that differ from vertebrate cartilages in having a noncollagenous extracellular matrix. Novel matrix proteins found in these cartilages include lamprin in the annular cartilage and an unidentified protein in the branchial cartilages. Both show biochemical similarities to elastin. The inextractability of these proteins, even to chemical cleavage by cyanogen bromide, indicates a polymer with extensive covalent cross-linking. Here we report on the type of cross-linking. Lysyl pyridinoline was found in high concentration in the elastin-like protein of lamprey branchial cartilage at a ratio of 7:1 to hydroxylysyl pyridinoline, the form that dominates in vertebrate collagens. Both forms of pyridinoline cross-link were absent from annular cartilage and desmosine cross-links, which are characteristic of vertebrate elastin, were not detected in either form of lamprey cartilage. Pyridinoline cross-links are considered to be characteristic of collagen, so their presence in an elastin-like protein in a primitive cartilage poses evolutionary questions about the tissue, the protein, and the cross-linking mechanism.

Topics: Amino Acids; Animals; Cartilage; Cattle; Chromatography, High Pressure Liquid; Collagen; Cross-Linking Reagents; Cyanogen Bromide; Elastin; Extracellular Matrix; Humans; Lampreys; Proteins; Spectrometry, Fluorescence

Urinary levels of collagen- and elastin-crosslink amino acids have been used as biologic markers for degradation of collagen and elastin in the body. Circadian variation of collagen-crosslink amino acids is well known. The current study was undertaken to determine whether there is also circadian variation in excretion of elastin-crosslink amino acids. We used an isotope dilution-HPLC assay to measure the elastin-crosslink amino acids, desmosine (DES) and isodesmosine (IDES), and the collagen-crosslink amino acids, hydroxylysyl pyridinoline (HP) and lysyl pyridinoline (LP), in urine. Sixteen apparently healthy subjects collected urine from 5:00 to 7:00 AM, and from 5:00 to 7:00 PM. Mean urinary excretion of DES and IDES in women was 56% and 41% higher (P < 0.001), respectively, in AM versus PM specimens when normalized by the creatinine content of the urine specimen. For men, the corresponding values were 11% and 13% higher (not statistically significant). Mean urinary excretion of HP and LP in women was 61% and 71% higher (P < 0.001), respectively, in AM versus PM specimens. For men, the corresponding values were 11% and 19% higher (not statistically significant). Differences were not found in the AM versus PM rates of excretion of creatinine in men or women. These findings demonstrate the occurrence of circadian variation in HP, LP, DES and IDES in women but not in men. We conclude that the time of collection of urine specimens, especially from women, must be taken into consideration in using the urinary levels of these crosslink amino acids as biologic markers for collagen or elastin degradation.

Topics: Adult; Amino Acids; Biomarkers; Circadian Rhythm; Collagen; Cross-Linking Reagents; Desmosine; Elastin; Female; Humans; Isodesmosine; Male; Middle Aged; Reference Values; Sex Characteristics

Collagen and elastin fibres are of major importance in providing the aorta with tensile strength and elasticity. The presence of cross-links in collagen and elastin is essential for the mechanical stability of collagen and elastin fibres. beta-aminopropionitrile (BAPN) reduces the formation of cross-links by inhibiting the enzyme lysyloxidase. Young rats were injected with BAPN to inhibit the formation of cross-links, and the changes in the biomechanical and biochemical properties of the thoracic aorta were studied. The biomechanical analyses of aortic samples from BAPN-treated rats showed a significantly increased diameter (1.64 +/-0.02 mm), a significantly reduced maximum load (1.08+/-0.08 N), and a significantly reduced maximum stiffness (3.34+/-0.10 N) compared with controls (1.57+/-0.02 mm, 1.55+/-0.04 N and 4.49 +/-0.14 N, respectively). No changes in the concentrations of collagen and elastin were found. The content of pyridinoline, a mature collagen cross-link, was significantly decreased by 49% in the BAPN-treated group compared with controls. No changes in the concentration of desmosine + isodesmosine, the major cross-links of elastin. were found. The present study shows that cross-links are essential in providing mechanical stability of the aorta. Even a partial inhibition of the cross-linking processes results in a destabilisation of the aortic wall with increased diameter and reduced strength and stiffness.

Topics: Aging; Amino Acids; Animals; Aorta; Collagen; Desmosine; Elasticity; Elastin; Female; Rats; Rats, Wistar; Structure-Activity Relationship

Previous studies have shown that biomechanical analysis of aorta from diabetic subjects reveals a marked increase in stiffness compared to aorta from age-matched control subjects. In the present paper we have proposed that this increased stiffness can be attributed to glycation-induced inter-molecular cross-links based on a direct analysis of the two known glycation cross-links, the fluorescent pentosidine and the non-fluorescent NFC-1. There was a significant difference in the increase in concentration of both cross-links with increasing age for both the intima (p < 0.0025) and the media (p < 0.0005) from the diabetic compared to the control subjects, but no correlation with the mature enzymic cross-link hy droxylysyl-pyridinoline. Finally, we have obtained a significant correlation of stiffness with both glycation cross-links (NFC-1, r = 0.86; p < 0.005 and pentosidine r = 0.75, p < 0.05), but the concentration of NFC-1 is about 50 times greater than that of pentosidine, indicating that it is the major glycation cross-link responsible for the stiffening of the aorta.

Topics: Adult; Aged; Aging; Amino Acids; Aorta, Thoracic; Arginine; Collagen; Cross-Linking Reagents; Diabetes Mellitus, Type 1; Diabetic Angiopathies; Elastin; Glycation End Products, Advanced; Humans; Lysine; Middle Aged; Time Factors

Topics: Aging; Amino Acids; Animals; Aortic Rupture; Cartilage, Articular; Collagen; Collagen Diseases; Disease Models, Animal; Disease Progression; Elastin; Enzyme-Linked Immunosorbent Assay; Female; Femur; Male; Mice; Mice, Inbred C57BL; Osteoarthritis; Protein-Lysine 6-Oxidase; Stifle; Tibia

It is well known that the elastic property of human aorta decreases gradually with age. Since the cross-linking structures are responsible for this elasticity, age-related changes of cross-linking amino acids in human aorta were studied using a high-performance liquid chromatography (HPLC). Non-atherosclerotic areas of thoracic aorta of 27 autopsy cases which had no particular aortic disease were obtained. After acid hydrolysis, SEP-PAK silica-gel column and Fe3+/activated charcoal column pretreatment were carried out for analysis of desmosine (DES), isodesmosine (ISDES), neodesmosine (NEO), oxodesmosine (OXO) and isooxodesomosine (ISOXO), and for analysis of aldosine (ALD), respectively. These prepared samples were applied to the reversed-phase HPLC column. We also analyzed pyridinoline (PYR), a major cross-linking amino acid of collagen as an index of fibrosis. All cross-linking amino acids of elastin rapidly increased in infancy and then gradually decreased with age. In the middle- and old-age, the amount of OXO showed marked variety. PYR was little detected at 0-year-old, and then gradually increased with age. The crosslinks of elastin were rapidly formed in childhood and then decreased with age. These findings suggest that the relative increase of NEO, OXO or ISOXO to DES and ISDES is associated with age-related weakening and/or damage of elastin, and that the gradual shift from elastin- to collagen-dominant state is a possible cause of the loss of elasticity and the gain of stiffness in the aging aorta.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Aging; Amino Acids; Aorta, Thoracic; Autopsy; Child; Child, Preschool; Chromatography, High Pressure Liquid; Cross-Linking Reagents; Desmosine; Elasticity; Elastin; Humans; Infant; Infant, Newborn; Isodesmosine; Middle Aged; Muscle Development; Muscle, Smooth, Vascular; Piperidines; Pyridines

During ageing and senescence the aorta becomes stiffer and its elasticity is reduced. The mechanism causing this increased stiffness of the aortic wall was studied using a rat model. Ring-shaped samples were prepared from the thoracic aorta of three groups of rats aged 4.5, 14 and 27 months, representing young, adult and old animals. Analysis of the static biomechanical properties showed increased diameter (2.20 +/- 0.03 mm) and increased stiffness (4.0 +/- 0.2 mN) of aortic samples from old rats compared with adult rats (1.82 +/- 0.02 mm and 3.0 +/- 0.1 mN, respectively). The total hydroxyproline and elastin content per sample was not changed. However, the hydroxyproline content/mm2 of the aortic wall was reduced by 20% and the elastin content/mm2 of the aortic wall was reduced by 19% comparing the old with the adult rats. No differences were found in the pyridinoline concentrations between old and adult rats. The collagen- and elastin-associated fluorescence was determined as a marker of advanced glycation endproducts (AGE). Both parameters were increased in the old rats compared with the adult rats by 42% and 17%, respectively, and positively correlated with stiffness at physiological loads. A positive correlation between collagen-associated fluorescence and maximum stiffness was found as well. In conclusion, the age-related increase in stiffness of the aorta was associated with increased diameter, reduced collagen and elastin contents/mm2 of the aortic wall, increased fenestration of elastic laminae and accumulation of fluorescent material in collagen and elastin.

Topics: Aging; Amino Acids; Animals; Aorta, Thoracic; Biomarkers; Biomechanical Phenomena; Blood Pressure; Calcium; Chromatography, High Pressure Liquid; Collagen; Elasticity; Elastin; Glycation End Products, Advanced; Hydroxyproline; Male; Rats; Rats, Wistar

Elastin degradation has been reported to be increased in patients with cystic fibrosis (CF). In order to further explore evidence for elastin degradation in a group of 18 patients with CF with a wide range of disease severity, we used an isotope dilution method to measure urinary desmosine (DES) and isodesmosine (IDES), amino acids derived exclusively from cross-linked elastin, and hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), amino acids derived exclusively from cross-linked collagen. Urinary DES and IDES (mean +/- SD) were 23.9 +/- 30.7 and 18.5 +/- 22.4 micrograms/g creatinine, respectively, in the patients with CF versus 7.5 +/- 1.7 and 6.8 +/- 1.4 micrograms/g creatinine, respectively, in 10 healthy control subjects (p < 0.001); only two patients with CF had DES values within the control range. The values of urinary HP and LP in the CF group were 54.9 +/- 39.1 and 12.3 +/- 8.6 nmol/mmol creatinine, respectively, versus 24.5 +/- 5.8 and 5.1 +/- 2.7 nmol/mmol creatinine, respectively, in the controls (p < 0.005). Both HP and LP were highly correlated (r = 0.71, p < 0.0001). Patients with CF had active pulmonary inflammation; neutrophils were abundant in the bronchoalveolar lavage fluid of the CF group and correlated with elastase activity measured with methoxysuccinyl Ala-Ala-Pro-Val paranitroanilide (r = 0.61, p < 0.05). Airway neutrophils had decreased expression of the complement receptor CR1 (CR1/CR3 of 0.17 +/- 0.15 versus 1.0 for blood neutrophils), a change known to be caused by uninhibited neutrophil elastase. We conclude that lung elastin is the most likely source of the increased DES and IDES in CF.

Topics: Adult; Amino Acids; Bronchoalveolar Lavage Fluid; Case-Control Studies; Collagen; Cystic Fibrosis; Desmosine; Elastin; Female; Humans; Isodesmosine; Leukocyte Elastase; Male; Neutrophils; Pancreatic Elastase; Receptors, Complement

One of the most rapid changes in collagen and elastin content of a tissue occurs in the uterus following postpartum involution. We measured the urinary excretion of specific amino acid markers for mature elastin (desmosine [DES] and isodesmosine [IDES]) and fibrillar collagen (hydroxylysyl pyridinoline [HP] and lysyl pyridinoline [LP]) before and after parturition in three gravid subjects. For that purpose, we used an isotope dilution method coupled with gel filtration and HPLC. The highest DES values were found 2-5 weeks postpartum and were 18-45 micrograms/g creatinine or two to six times those found for healthy neversmoking nongravid females (7.7 +/- 0.3 micrograms/g creatinine, mean +/- SE). The highest levels of urinary HP for each subject were found 2-3 weeks after parturition and were 115-607 nmol/mmol creatinine or 4-21 times those found for healthy neversmoking nongravid females (28.1 +/- 1.3 nmol/mmol creatinine). For the gravid subjects as a group and also for each subject, the mean values for urinary DES, IDES, HP, and HP/LP during the first 6 weeks postpartum were significantly greater than the mean baseline values beginning 27 weeks postpartum. For the gravid subjects as a group, the mean value for urinary HP/LP during the first 6 weeks postpartum was significantly greater than the value during the 20 weeks preceding parturition. This suggested that the tissue(s) of origin of the excess HP, during the 6 weeks following parturition, was not bony and was consistent with a uterine origin.

Topics: Amino Acids; Collagen; Creatinine; Desmosine; Elastin; Female; Humans; Kinetics; Postpartum Period; Pregnancy; Reference Values; Smoking; Uterus

It has been hypothesized that emphysema results from damage to the elastic fiber network of the lungs as a result of elastase-antielastase imbalance. We used a new assay for urinary desmosine (DES) and isodesmosine (IDES), specific markers for the degradation of mature crosslinked elastin, and hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP), specific markers for the degradation of mature crosslinked collagen, in order to examine elastin and collagen degradation in relation to current cigarette smoking and the presence of chronic obstructive pulmonary disease (COPD). The study sample consisted of 22 never-smokers (NSM group), 13 current smokers without airflow obstruction (SM group), and 21 patients with COPD (COPD group), including both current and former smokers. The relation between the creatinine-height index and FEV1 was used to correct for possible loss of muscle mass and decreased excretion of creatinine in the COPD group. Mean urinary excretion of elastin-derived crosslinks in the COPD group (DES, 11.8 +/- 5.1 [mean +/- SD]; IDES, 11.3 +/- 5.0 micrograms/g creatinine) and in the SM group (DES, 11.0 +/- 4.2; IDES, 10.2 +/- 2.5 micrograms/g creatinine) was significantly higher than in the NSM group (DES, 7.5 +/- 1.4; IDES, 6.9 +/- 1.3 micrograms/g creatinine). In multivariate analysis, current smoking and the presence of COPD were significantly and independently associated with higher urinary excretion of elastin degradation products, and there was no significant interaction between current smoking and the presence of COPD.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Amino Acids; Biomarkers; Collagen; Desmosine; Elastin; Female; Humans; Isodesmosine; Lung Diseases, Obstructive; Male; Middle Aged; Prospective Studies; Smoking

To measure the urinary excretion of specific cross-link amino acid markers for mature elastin (desmosine [DES] and isodesmosine [IDES]) and fibrillar collagen (hydroxylysylpyridinoline [HP] and lysylpyridinoline [LP]) in systemic sclerosis (SSc) patients and healthy controls.. Urine specimens from 20 patients with SSc and 22 controls were assessed for DES, IDES, HP, and LP using high performance liquid chromatography and ultraviolet absorption spectroscopy, in combination with an isotope dilution technique in which the urine specimen was spiked with isotopically labeled cross-link amino acids.. Mean +/- SD levels of urinary DES and IDES were elevated in SSc patients by 2-3-fold, and urinary HP and LP by 3-4-fold, compared with controls (DES 21.0 +/- 9.4 versus 7.5 +/- 1.4 micrograms/gm creatinine; HP 109.0 +/- 72.9 versus 24.9 +/- 5.7 nmoles/mmole creatinine). Nineteen of the 20 SSc patients had urinary DES and HP values that were > 3 SD above the control mean. A significant elevation in the HP:LP ratio in SSc patients as compared with controls (mean +/- SD 6.9 +/- 1.5 versus 5.5 +/- 1.3) indicated a soft tissue origin for much of the increased HP.. Patients with SSc have higher levels of urinary cross-link amino acids specific for the degradation of mature collagen and elastin. These markers distinguish most SSc patients from healthy controls.

Topics: Adult; Aged; Amino Acids; Collagen; Desmosine; Elastin; Female; Humans; Isodesmosine; Male; Middle Aged; Reference Values; Scleroderma, Systemic

It is hypothesized that emphysema develops in some severely alpha 1-antitrypsin (AAT)-deficient persons because endogenous elastases are not adequately controlled by AAT, and accelerated elastin degradation occurs. It is not known whether augmentation therapy with AAT diminishes degradation of lung elastin in severely deficient persons with lung disease. Two severely deficient, PiZ patients were studied, a 63-year-old never-smoking woman with bronchiectasis and a 41-year-old smoking man with emphysema. Urinary desmosine (DES) was determined before and after augmentation therapy with AAT, 260 mg/kg/month. Mean +/- SEM pretreatment urinary DES was elevated in both patients, 19.7 +/- 0.9 (n = 2) and 10.8 +/- 0.2 (n = 2) micrograms/g creatinine, respectively, compared to normal values of 7.5 +/- 0.3 (n = 22) micrograms/g creatinine. Following augmentation therapy, urinary DES values decreased 40 and 36%, respectively, to 11.9 +/- 0.3 (n = 8) and 6.9 +/- 0.4 (n = 7) microgram/g creatinine (p < 0.05). We conclude that monthly AAT augmentation therapy decreased DES excretion in the urine of these PiZ patients. We speculate that since there was lung disease in both patients, a decrease in degradation of lung elastin is the most likely explanation for this observation.

Topics: Adult; alpha 1-Antitrypsin; alpha 1-Antitrypsin Deficiency; Amino Acids; Bronchiectasis; Desmosine; Elastin; Emphysema; Female; Humans; Isodesmosine; Lung; Male; Middle Aged; Smoking

To help validate the use of urinary desmosine (DES), isodesmosine (IDES), and hydroxylysyl pyridinoline (HP) as specific markers of host elastin and collagen degradation, respectively, a study was carried out on the effect of dietary elastin and collagen on urinary DES, IDES, and HP. Ingestion of a meal of calf ligamentum nuchae containing 33 g elastin, 500 mg DES, and 400 mg IDES produced a 10-fold increase in urinary DES and an 8-fold increase in IDES. The urinary DES values remained elevated for more than 10 days following the ingestion. We estimate that about 0.3 mg, or < 0.1%, of the ingested DES was excreted in the urine. Since ligamentum nuchae is not a usual ingredient of human diets, we also determined whether a more typical source and amount of DES, IDES, and HP might affect urinary DES, IDES, or HP values. Lean ground beef (454 g) was ingested. Our analysis showed that this meal contained 4 mg DES, 2 mg IDES, and 0.9 mg HP. The meat-rich diet caused a significant increase of 16 and 34% in the creatinine and DES content of the urine, respectively. When DES, IDES, and HP values were normalized for the urine creatinine content, diet had no effect on the measured amounts. The baseline values (mean +/- SE) for the volunteers before ingestion of the beef were 8.3 +/- 0.7 micrograms DES/24 h, 8.3 +/- 0.6 micrograms IDES/24 h, and 340 +/- 48 nmol HP/24 h; 5.7 +/- 0.5 micrograms DES/g creatinine, 5.6 +/- 0.4 micrograms IDES/g creatinine, and 26.9 +/- 2.2 nmol HP/mmol creatinine.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Amino Acids; Analysis of Variance; Animals; Bias; Biomarkers; Cattle; Chromatography, High Pressure Liquid; Collagen; Creatinine; Desmosine; Diet; Dietary Proteins; Elastin; Humans; Isodesmosine; Male; Meat; Reproducibility of Results

Inhibition ELISA assay was used to examine the cross-reaction of the polyclonal anti-desmosine antiserum produced in rabbit against molecules possessing a "pyridinium ring" as their core structure i.e. isodesmosine, pentasine, pyridinoline and 2'-deoxypyridinoline, highly purified with column chromatography, and structurally unrelated substances, i.e. cysteic acid, taurine and 2-aminopyridine (core structure of desmosine). No cross-reaction was observed to the pyridinoline, 2'-deoxypyridinoline possessing "pyridinium ring" and derived from collagen cross-links, structurally unrelated cysteic acid and taurine, nor core structure of 2-aminopyridine. The antiserum specifically recognized the molecules derived from the elastin cross-links. Using the ELISA assay system with antisera and amino acids analysis, 10 micrograms of desmosine were extracted from 1.0 mg of the hydrolysate of commercial elastin.

Topics: Amino Acids; Animals; Antibodies; Antibody Specificity; Cross Reactions; Desmosine; Elastin; Enzyme-Linked Immunosorbent Assay; Rabbits

The wet weight of the rat uterus increased 8-fold during pregnancy and fell by 70% within 5 days postpartum. Uterine collagen increased about 5-fold during pregnancy and also fell by 70% within 5 days. The crosslink pyridinoline remained constant at 0.28 mole/mole collagen at every time point, with the possible exception of 11-12 days of pregnancy. The pyridinoline link can therefore form within the short time span of a few days, a feature presumed to be necessary to maintain the full mechanical strength of the uterus during labor. Uterine elastin increased about 8-fold during pregnancy, but the desmosines did not keep pace and fell from a normal value of 1.43 mole/mole elastin to a low of 0.89 at term. Moreover, elastin content reached a maximum several days prior to parturition and then declined continuously to 5 days postpartum. During this decline there was a selective loss of the poorly crosslinked elastin. The desmosines cannot be used as a direct measure of uterine elastin content, because of their continuously changing levels. Desmosines and pyridinoline were measured both by ELISA and by the amino acid analyzer. The two methods gave almost identical results when elastin and collagen were first separated from each other.

Topics: Amino Acids; Animals; Collagen; Desmosine; Elastin; Female; Organ Size; Pregnancy; Pregnancy, Animal; Rats; Rats, Inbred Strains; Uterus

The present study was undertaken to examine malignant alterations of collagen and elastin in human stomach cancer. Results of the study are as follows: 1. Content of hydroxyproline which in characteristic amino acid in collagen was elevated in stomach cancer tissues of Bormann types I to IV as compared to that of the uninvolved stomach. 2. When hydroxyproline content in stomach cancer of type IV (scirrhous) was compared to that in other types (I to III) of the cancer, the content in scirrhous was significantly elevated compared with that in cancers of other types, in terms of dry weight of whole tissue, number of cancer cells, and of insoluble proteins which are rich in collagen and elastin. However, when hydroxyproline was determined on two histological layers (mucosa plus submucosa layer and muscular plus serosa layer) separated from the involved and uninvolved stomach tissues, no significant difference in hydroxyproline content was observed between the scirrhous and non-scirrhous cancers. These observations may imply that an increased collagen synthesis in the scirrhous occurs in many layers of stomach tissue but is not restricted in a particular layer. 3. Non-reducing cross-link amino acids of collagen, pyridinoline and histidinoalanine, were assayed on the involved and uninvolved tissues. Pyridinoline content was higher in stomach cancers of Bormann types I to IV, while no significant difference of histidinoalanine content was found. These observations suggest that there is an increased cross-linking of collagen in stomach cancer. 4. Elastin concentration in stomach cancer was determined through the assay of desmosine and isodesmosine which are specific cross-link amino acids in elastin. The contents of these amino acids was increased in stomach cancer tissues of types I to IV as compared with that in the uninvolved tissue. 5. A ratio of desmosine plus isodesmosine to hydroxyproline was higher in the involved stomach than was in the uninvolved, suggesting that increased elastinosis exceeds collagenosis in stomach cancer.

Topics: Amino Acids; Collagen; Dipeptides; Elastin; Humans; Hydroxyproline; Stomach Neoplasms

Topics: Amino Acids; Aminopropionitrile; Animals; Chemical Phenomena; Chemistry; Collagen; Elastin; Hydrazines; Lathyrism; Male; Oxalates; Penicillamine; Pyridinium Compounds; Rats; Rats, Inbred Strains; Semicarbazides

It has been shown that, contrary to desmosine and isodesmosine, the content of pyridinoline increases in elastin preparations obtained from rat and bovine aortae and from bovine ligmentum nuchae throughout the whole lifespan. The molar proportion of this cross-linking amino acid is within the range of 0.6 - 2.5 leucine equivalents per 100 amino acid residues.

Topics: Aging; Amino Acids; Animals; Cattle; Chromatography, Gel; Elastin; Ligaments; Muscle, Smooth, Vascular; Rats; Spectrometry, Fluorescence

Two fluorescent fractions were found in total acid hydrolysate of elastin. The fraction with higher chromatography mobility in isopropyl alcohol/conc. ammonia/water (9 : 1 : 2) was purified by multiple preparative paper chromatography in the same solvent system, and by gel chromatography on Sephadex G-25, ion-exchange chromatography on phosphocellulose and another gel chromatography on Sephadex G-10. The purified material was chromatographically homogeneous, had an ultraviolet absorption maximum at 315 nm and exhibited a strong 320/405 nm fluorescence. 1H- and 13C-NMR spectra were in good agreement with those published previously [6] for pyridinoline, a lysine derived fluorescent compound in collagen. The major part of the fluorescent material present in acid hydrolysate of elastin was always contaminated, even after complex purification procedures. It is concluded that elastin contains several fluorophores, one of which is a cross-linking tricarboxylic amino acid with a pyridinium ring having very probably the structure of 3-(2-amino-2-carboxyethyl)-1-(5-amino-5-carboxy-2-hydroxy-pentyl)-4-(3-amino-3- carboxypropyl)-5-hydroxypyridinium. The position of 2-amino-2-carboxyethyl and 3-amino-3-carboxypropyl residues has not been definitely established and can be interchanged.

Topics: Amino Acids; Chemical Phenomena; Chemistry; Collagen; Elastin; Hydrolysis; Pyridinium Compounds; Spectrometry, Fluorescence