Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Hydroxyproline”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources

Biological variation in free serum hydroxyproline concentration.

Improvements in the accuracy of single estimations of biochemical constituents such as the serum free hydroxyproline (FSHP) concentration can only result from control of biological variation as well as analytical variation. In this context two experiments were carried out to determine whether a significant diurnal rhythm in FSHP concentration exists in man, and whether a worthwhile reduction in intra-individual variance can be achieved by eliminating dietary sources of hydroxyproline. A significant (p < 0.001) diurnal variation in FSHP concentration was detected in a group of normal subjects, with a range of about 20% of the mean. In a second group of eight normal subjects, there was a substantial reduction in the within-subject variation after the start of dietary control. For the most precise determination of FSHP concentration therefore, dietary hydroxyproline sources must be controlled, preferably eliminated, and blood should be sampled at a standardised time of day.

Adult↗

A case of an exceptionally high level of urinary-4-hydroxyproline containing polypeptides.

The determination of total urinary-4-hydroxyproline in an adolescent showed a very high excretion of hydroxyproline containing peptides: 26.2 mmol/24 h. Estimation of total urinary 3-hydroxyproline and peptide fractionation on Biogel P 2 demonstrated unusual features. Such cases are of great interest for structural studies of the urinary polypeptides and understanding of collagen catabolism.

Adolescent↗

Hydroxyproline and hydroxylysine in different tissues of human embryos.

The collagen content in various tissues of human embryos was studied at four different steps of the maturation process. The umbilical cord of a 16-17 week old embryo was found to be active in collagen biosynthesis, Tibia, articular cartilage and skin showed of a peak of total hydroxyproline in the 16-17th week, decreasing later on, while the hydroxyproline decreased in umbilical cord from the 15-16th week to the 24th week. Hydroxylysine followed the hydroxyproline changes in articular cartilage and umbilical cord.

Bone and Bones↗

Determination of radioactive proline and hydroxyproline by a simple paper-chromatographic procedure.

A simple method to separate and determine radioactive proline and hydroxyproline by paper chromatography is described. The localization of the imino acids after separation is achieved by direct nondestructive staining with 1-fluoro-2,4-dinitrobenzene dye. The imino acids are quantitated directly by liquid scintillation counting in the presence of paper strips. The method was applied to bone cultures with good reproducibility, sensitivity and linearity over a wide range of radioactivity. The procedure was also tested in fibroblast cultures. The results for hydroxyproline were in good correlation with the widely used method of Juva and Prockop (Juva, K. and Prockop, D.J. (1966) Anal. Biochem. 15, 77-83), in which hydroxyproline is oxidized to pyrrole, and then extracted and purified by column chromatography before counting radioactivity.

Animals↗

Ascorbate increases the synthesis of procollagen hydroxyproline by cultured fibroblasts from chick embryo tendons without activation of prolyl hydroxyla.

An improved procedure was developed to extract prolyl hydroxylase from tendon cells of chick embryos with detergent, and improved assays were developed for both the activity of the enzyme and the amount of enzyme protein. Freshly isolated tendon cells were found to contain approx. 100 mug of enzyme protein per 10(8) cells and 40-50% of the enzyme protein was active. When the cells were cultured, they were found to contain the same amount of enzyme protein but only 15-20% of the enzyme protein was active. Gel filtration of cell extracts indicated that the active form of prolyl hydroxylase in freshly isolated tendon cells and incultured tendon cells had the same apparent size and the same activity per mug of immunoreactive protein as enzyme which was shown to be a tetramer. The inactive form was found to have about the same apparent size as subunits of the enzyme. When freshly isolated cells were incubated for 2 h in the presence of 40 mug per ml of ascorbate, there was a slight increase in the rate of hydroxyproline synthesis. In cultured cells, ascorbate at a concentration of 40 mug per ml caused a 2-fold increase in the rate of hydroxyproline synthesis within 30 min. However, ascorbate did not icrease the activity of prolyl hydroxylase in extracts from either cell system. Therefore it appears that the influence of ascorbate on synthesis of procollagen hydroxyproline by the cells studied here must be ascribed to a cofactor effect on the hydroxylation reaction similar to that observed with purified enzyme, and it does not involve "activation" of inactive enzyme protein to active enzyme as has been observed in cultures of L-929 and 3T6 mouse fibroblasts.

Animals↗

Effect of intratracheally administered anticancer drugs on lung hydroxyproline content.

The systemic administration of the anticancer drug bleomycin is associated with the development of lung damage and fibrosis. Intratracheal (i.t.) instillation of bleomycin has often been employed in animal models of this lesion to more rapidly elicit lung damage. However, various drugs and chemicals are known to induce lung damage and fibrosis when given i.t. The results presented here demonstrate that, in addition to bleomycin, the i.t. instillation of dactinomycin, mitomycin c, doxorubicin, and cyclophosphamide resulted in increased lung levels of hydroxyproline, an indicator of fibrosis. In contrast, increases were not seen following i.t. doses of 5-fluorouracil or vincristine, and 1,3-bis(2-chloroethyl)-1-nitrosourea(BCNU) actually decreased lung hydroxyproline content. These findings suggest that i.t. treatments with bleomycin may produce lung damage more representative of anticancer drugs in general than the specific lesion which is produced when bleomycin is administered systemically. The mechanisms underlying i.t. drug-induced increases in lung hydroxyproline are not known, but may be related to the ability of cell-cycle-nonspecific anticancer drugs to directly damage alveolar epithelial cells.

Animals↗

Pulmonary hydroxyproline content and production following treatment of mice with O,S,S-trimethyl phosphorodithioate.

The systemic administration of O,S,S-trimethyl phosphorodithioate (OSS), a contaminant of various organophosphorus insecticides, induces delayed damage to rat and mouse lung tissue. The lesion, particularly in the rat, closely resembles that produced by butylated hydroxytoluene (BHT) in mice. Although the time course of cell damage and repair has been studied in both species, it is not clear whether excess collagen, indicative of fibrosis, is deposited. Changes in pulmonary hydroxyproline content and synthesis, indices of collagen metabolism, were analysed in mice treated with 45 mg/kg OSS. A significant increase in total lung hydroxyproline was evident 21 days after treatment compared to both pair-fed and ad libitum controls. This increase was not augmented by subsequent treatment with 35 mg/kg 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) or exposure to 70% oxygen for 7 days. The rate at which lung tissue synthesized hydroxyproline was increased 7-14 days after treatment with OSS. These data demonstrate that treatment of mice with OSS results in changes indicative of pulmonary fibrosis. However, in contrast to some other lung-toxic chemicals, this lesion was not enhanced by subsequent treatment with BCNU or hyperoxia.

Animals↗

Microderivatization of 4-[18O]hydroxyproline and quantitation with a benchtop mass spectrometer.

Accurate estimation of in vivo turnover rates of collagen is complicated by amino acid reutilization. It was previously shown that the ideal, non-recycling tracer was [18O]hydroxyproline synthesized in vivo. The analytical method for measuring turnover rates with [18O]hydroxyproline must include analyte quantitation for pool size determination and isotope ratio measurement for determining levels of label incorporation. For ease of use and widest availability, a benchtop gas chromatograph-mass spectrometer in the electron-impact ionization mode was chosen. Here we present a versatile procedure for hydroxyproline derivatization that is well suited for routine, large-scale determination of analyte concentrations and relative levels of 18O incorporation.

Animals↗

Evaluation of wound healing of the teat with and without low level laser therapy in dairy cattle by laser Doppler flowmetry in comparison with histopathology, tensiometry and hydroxyproline analysis.

Perforated teat wounds in eight lactating Holstein-Friesian cows were closed by four suture patterns with or without low level laser therapy (LLLT). Wound healing was evaluated by laser Doppler flowmetry (LDF), tensiometry and hydroxyproline analysis, and compared with histopathological examination. The three-layer pattern provided the best healing of the entire teat. Mucosal hyperplasia was observed in Gambee and continuous two-layer pattern while eversion of the skin, presence of suture tracts and a greater amount of granulation tissue were observed with the continuous and interrupted two-layer patterns. The epidermis in LLLT groups more closely resembled the normal epidermis, and collagen fibres were denser, thicker and better arranged in LLLT than in non-LLLT groups. LDF, tensiometry and hydroxyproline analysis correlated well with histopathological examination. The results suggest that LDF, a more rapid, less invasive and painless procedure, can replace tensile strength measurement or hydroxyproline analysis to assess the progress of teat wound healing.

Animals↗

Hydroxyproline as a marker for following patients with metastatic prostate cancer.

Serial measurements of urinary hydroxyproline excretion were performed in 16 patients with stage D2 prostatic cancer to evaluate its role as a marker for following disease course. Patients were defined as having stable or progressive disease by the criteria of the National Prostatic Cancer Project. For patients with stable disease and those with disease progression excretion of hydroxyproline did not correlate with the clinical course. We did not find that hydroxyproline was a useful marker in the clinical setting to follow patients with prostatic cancer.

Bone Neoplasms↗

Identification of a novel hydroxyproline-rich glycoprotein as the major allergen in Parthenium pollen.

BACKGROUND: The airborne pollen of the Compositae weed, Parthenium hysterophorus, is a major cause of allergic rhinitis in the Indian subcontinent and in certain parts of the southern United States and western Australia. Earlier studies have identified a 31 kd protein as the major allergen in Parthenium pollen. OBJECTIVE: This study was undertaken to carry out the purification, immunochemical characterization, sequencing, and epitope analysis of this major allergen, designated as Par h I. METHODS: The IgE-binding activity of the allergen was evaluated by immunoblot and inhibition ELISAs. Pronase digestion, periodate oxidation, and chemical deglycosylation were performed to determine the role of peptide and carbohydrate components of the allergen in IgE binding. RESULTS: The data provide evidence for the involvement of carbohydrate moieties on Par h 1 in its IgE-binding ability. The N-terminal 91 amino acid sequence of Par h 1 shows 81% identity with a protein from sunflower anther, and the hydroxyproline-rich region of Par h 1 is 30% to 40% identical to similar stretches in extensins, a class of hydroxyproline-rich cell wall glycoproteins from different plant species. IgE antibodies in the sera of individuals allergic to Parthenium cross-reacted with a 50 kd hydroxyproline-arabinose-rich extensin precursor from potato tuber, and this binding was periodate-sensitive. CONCLUSIONS: It appears that a group of soluble plant glycoproteins, which are related to the ubiquitous extensins, have certain carbohydrate-containing IgE-binding epitopes that may contribute to allergenic cross-reactivity among specific pollens and foods.

Allergens↗

Polymorphism of urinary 4-hydroxyproline-containing polypeptides.

Using molecular sieve chromatography on Bio-Gel P-2 and then on Bio-Gel P-30, hydroxyproline-containing urinary polypeptides (molecular weight greater than 1500 daltons) were separated into eight fractions. The three main fractions were separated further on phosphocellulose giving seven, nineteen and twelve peaks, respectively, each containing 4-hydroxyproline. Hypotheses about the origin of certain polypeptides are proposed, which take into account the sequence of type I collagen. Among these 38 polypeptides only one shows a quantitative variation in Paget's bone disease and was thus purified. It consists of equal amounts of glycine, proline and 4-hydroxyproline. This particular polypeptide may originate from the N-terminal propeptide of type I collagen.

Amino Acids↗

Rapid screening of urinary proline-hydroxyproline dipeptide in bone turnover studies.

In a recent report [J. Chromatogr. B 678 (1996) 165] a urinary hydroxyproline-containing peptide has been preliminarily suggested as a possible alternative to hydroxyproline (HP) determination in bone resorption studies. For this purpose a simple and practical procedure was developed for a rapid high-performance liquid chromatographic (HPLC) assay of the peptide in non-hydrolyzed urine samples. Hundreds of randomly selected urine samples were assayed for both the peptide and HP, the latter in hydrolyzed urine, and a high correlation between them was found. The promising results prompted us to search for the postulated biomarker of bone resorption in urine samples of postmenopausal women examined as osteoporosis suspects. As an alternative to the HPLC determination, an equally rapid procedure has been developed for the peptide assay using capillary gas chromatography (GC) with flame ionization detection (FID). By means of a solid-phase and a liquid-liquid phase extraction, involving ethyl chloroformate (ECF) as the derivatizing agent, two dipeptides and some urinary amino acids could be analyzed within 5 min. A high correlation between both HPLC and GC peptide assay was confirmed (r=0.944) and the compound was identified as proline-hydroxyproline (PHP) dipeptide.

Chromatography, Gas↗

Tuberous sclerosis: proline and hydroxyproline contents in serum.

The serum levels of proline and hydroxyproline were determined by high-performance liquid chromatography using the post-labeled method with o-phthalaldehyde and sodium hypochlorite in 30 patients of tuberous sclerosis (TS) and compared with those in 32 pathological control subjects of similar age. No significant difference in the levels of serum free hydroxyproline was observed between TS and controls in any age group. In the age group of 9 to 18 years, TS showed significantly higher mean free proline levels in serum than controls with a difference of about 50 mumol/L. In both groups of TS and controls, total and free levels of hydroxyproline from ethanol-extractable serum showed similar age-dependent curves with peak values at age 12 years, and there was also no difference in the 2 levels between the 2 groups. It is suggested that this higher free proline level in TS with the autosomal dominant trait may be explained as the abnormal regulation of proline metabolism.

Adolescent↗

Potato lectin: a three-domain glycoprotein with novel hydroxyproline-containing sequences and sequence similarities to wheat-germ agglutinin.

Potato (Solanum tuberosum) tuber lectin is a chitin-binding, hydroxyproline-rich glycoprotein, which may be involved in the defence mechanism of the plant. We had previously obtained evidence that it consists of at least two very dissimilar domains. The aim was to use a combination of accurate determinations of molecular weight and protein sequencing to gain more accurate information on the domains. Accurate determinations of the molecular weight of the lectin by a MALDI mass spectrometer have shown that the subunit molecular weight is 65,500 (+/- 1100) and that of a totally deglycosylated sample is 31,250 (+/- 30). This means that the lectin is 52.3 (+/- 1)% carbohydrate with a considerable number of glycoforms being present. Partial sequences and other analyses are consistent with the existence of three distinct domains. These are: (1) an N-terminal region which is rich in proline but poor in hydroxyproline; (2) a glycosylated region with a glycosylated molecular weight of 45,300 (+/- 1100) and a deglycosylated molecular weight of 11,050 (+/- 50) which is extremely rich in glycosylated hydroxyproline residues with a similar sequence to extensins; and (3) a cystine-rich domain which has the sugar binding site shows partial conservation of a repeated motif common to many chitin-binding proteins of the hevin family including wheat-germ agglutinin. The closest similarity seems to be to the sequence of potato basic chitinase.

Amino Acid Sequence↗

Analysis of bromotryptophan and hydroxyproline modifications by high-resolution, high-accuracy precursor ion scanning utilizing fragment ions with mass-deficient mass tags.

Protein modifications are often detected by precursor ion scanning. When quadrupole TOF mass spectrometers are used for precursor ion scanning with high-resolution, high-accuracy fragment ion selection, "reporter" ions are required to have a unique mass within +/-0.04 Da or less instead of +/-0.5 Da on triple quadrupole mass spectrometers, the traditional instrument used for precursor ion scanning. Thus, characteristic fragment ions can be utilized even if other fragment ions have the same nominal mass as long as the characteristic fragment ions are slightly mass deficient as compared to the other fragments, i.e., when they have an inherent mass-deficient mass tag. Here, the immonium ions of bromotryptophan and hydroxyproline are described as two fragment ions characteristic for tryptophan-brominated and proline-hydroxylated peptides, respectively. The "reporter" ion of trytophan-brominated peptides is highly mass deficient due to the presence of bromine, thereby allowing the selective detection of these species and the distinction from other dipeptidic a-, b-, and y-fragment ions by high-resolution, high-accuracy precursor ion scanning. This strategy also enables the differentiation between precursors giving rise to the oxygen-containing immonium ion of hydroxyproline and precursors of the immonium ions of near-ubiquitous leucine/isoleucine. Both immonium ions have the same nominal mass of 86 Da, but the exact masses differ by less than 0.04 Da. High-resolution, high-accuracy precursor ion scanning enabled the identification of proline-hydroxylated and tryptophan-brominated species and the directed analysis of species carrying these modifications in a highly complex Conus textile conotoxin mixture. This lead to the characterization of one novel C. textile conotoxin containing a bromotryptophan residue and one novel C. textile conotoxin carrying two hydroxyproline residues.

Animals↗

Isolation and characterization of a hydroxyproline-containing protein from soluble extracts of the leaves of sandal (Santalum album L.).

1. A hydroxyproline-containing protein was isolated from the soluble fraction of sandal leaves (Santalum album L.) and the purified protein was homogeneous by disc electrophoresis. 2. It is a glycoprotein containing 16% carbohydrate, the components of which were mainly arabinose, with only small amounts (about 5%) of galactose. The principal amino acids were glutamic acid, aspartic acid, glycine, alanine, arginine, lysine, proline and hydroxyproline, which together comprised 60% of the total. The number of acidic amino acids exceeds the number of basic amino acids. By Sephadex gel filtration, the approximate molecular weight was found to be about 63000. The ratio of residues of hydroxyproline to those of arabinose was 1:2. 3. The native protein is resistant to the action of several proteolytic enzymes. After partial hydrolysis with 0.1m-HCl, the protein became susceptible to attack by Pronase but remained resistant to collagenase.

Alanine↗

Characterization of the hydroxyproline-rich protein core of an arabinogalactan-protein secreted from suspension-cultured Lolium multiflorum (Italian ryegrass) endosperm cells.

An arabinogalactan-protein (AGP) purified from the filtrate of liquid-suspension-cultured Italian-ryegrass (Lolium multiflorum) endosperm cells by affinity chromatography on myeloma protein J539-Sepharose was deglycosylated with trifluoromethanesulphonic acid to remove polysaccharide chains that are covalently associated with hydroxyproline residues in the peptide component of the proteoglycan. The protein core, which accounts for less than 10% (w/w) of the intact proteoglycan, was purified by h.p.l.c. It has an apparent Mr of 35,000, but reacts very poorly with both Coomassie Brilliant Blue R and silver stains. Amino-acid-sequence analysis of the N-terminus of the h.p.l.c.-purified protein core and of tryptic peptides generated from the unpurified protein reveals a high content of hydroxyproline and alanine. These are sometimes arranged in short (Ala-Hyp) repeat sequences of up to six residues. Polyclonal antibodies raised against the protein core do not cross-react with native AGP, the synthetic peptide (Ala-Hyp)4, poly-L-hydroxyproline or poly-L-proline. The results suggest that the polysaccharide chains in the native AGP render the protein core of the proteoglycan inaccessible to the antibodies and that the immunodominant epitopes include domains of the protein other than those rich in Ala-Hyp repeating units.

Amino Acid Sequence↗