Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Procollagen”

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 1,099 records · Page 61Linked to original sources
PubMed1990

D-periodic assemblies of type I procollagen.

The solubility limit of purified chick type I procollagen, incubated at 37 degrees C in phosphate-buffered saline, was found to be in the range 1 to 1.5 mg/ml. At higher concentrations large aggregates formed. These comprised: (1) D-periodic assemblies; (2) narrow filaments with no apparent periodicity; and (3) segment-long-spacing-like aggregates. The D-periodic assemblies, which predominated at high concentrations, were separated from the other types of aggregate and found to be ribbon-like. Ribbons were uniform in thickness (approximately 8 nm) and up to 1 micron wide. Staining patterns showed features similar to those in native-type collagen fibrils. Immunolabelling indicated that the carboxyl-terminal propeptide domains were close to the carboxyl-terminal gap-overlap junction, and that the amino-terminal propeptide domains were folded over into the amino-terminal side of the overlap zone. Both propeptide domains appeared to be located on the surface of the assemblies. These observations show that intact propeptide domains hinder, but do not prevent, the formation of D-periodic assemblies. The presence of the propeptide domains on the surface of a growing assembly could restrict its lateral growth and limit its final thickness.

Animals↗
PubMed1991

The carboxy-terminal propeptide of type I procollagen in serum as a marker of bone formation: the effect of nandrolone decanoate and female sex hormones.

Seventy-nine osteoporotic (prior forearm or vertebral fracture), but otherwise healthy, postmenopausal women (aged 55 to 75 years) were allocated to two double-blind trials: (1) 39 women received either nandrolone decanoate (anabolic steroid) 50 mg as an intramuscular depot injection or a placebo injection every 3 weeks for 1 year; and (2) 40 women received either 2 mg 17 beta-estradiol plus 1 mg norethisterone acetate or placebo tablets daily for 1 year. Sixty-seven (85%) completed the 1 year of treatment. Serum concentration of type I procollagen carboxy-terminal propeptide (PICP) was measured before and at 3, 6, 9, and 12 months of therapy. In addition, 32 of the women had an iliac bone biopsy taken after double tetracycline labeling. Initial serum PICP correlated significantly with histomorphometrically measured rate of bone formation (r = .4; P less than .05) and plasma bone Gla protein (r = .6; P less than .001), but not with histomorphometrically measured bone resorption or biochemical estimates of bone resorption (fasting urinary hydroxyproline and calcium). Estrogen-progestogen therapy significantly decreased (P less than .001) serum PICP by about 30%, whereas anabolic steroid therapy hardly affected it. We conclude that serum PICP may be used as a noninvasive measurement of bone formation on a group basis. Whereas bone formation is clearly decreased during estrogen-progestogen therapy, it is not affected by long-term therapy with anabolic steroids.

Aged↗
PubMed1994

Reduced serum levels of carboxy-terminal propeptide of human type I procollagen in a family with type I-A osteogenesis imperfecta.

We measured serum levels of total alkaline phosphatase activity, osteocalcin, carboxy-terminal propeptide of human type I procollagen (PICP), tartrate-resistant acid phosphatase activity (TRAP), and the fasting urinary hydroxyproline/creatinine ratio (OHPr/Cr) in seven affected members (four men, three women; age, 43.3 +/- 16.6 years [mean +/- SD]) of a family with clinically diagnosed type I-A osteogenesis imperfecta (OI) and in eight (five men, three women) normal age-matched (38.2 +/- 10.3) relatives. Three boys with OI and three normal girls of the same family were also studied, although they were excluded from statistical analysis. Bone mineral density was also determined at four different skeletal sites. Serum levels of PICP were measured with a radioimmunoassay (Farmos Diagnostica, Turku, Finland). There were no significant differences in mean values of the biomarkers studied between OI patients and normal relatives, with the only exception being serum levels of PICP (35 +/- 7.5 v 219 +/- 107.5 micrograms/L, P < .001). A significant reduction of BMD was found in OI patients compared with normal relatives at the lumbar (L) spine (680 +/- 61 v 1,128 +/- 92 mg/cm2, P < .001), at the ultradistal radius ([UDR] 323 +/- 85 v 458 +/- 76, P < .006), at the femoral neck ([F] 494 +/- 140 v 791 +/- 104, P < .001), and at the junction of the distal and middle third of the radius ([MR] 639 +/- 71 v 717 +/- 52, P < .029).(ABSTRACT TRUNCATED AT 250 WORDS)

Acid Phosphatase↗
PubMedDate not supplied

Aminopropeptide of human procollagen type I: a marker for the identification of blood from children in the mosquito blood meal.

A capture enzyme-linked immunosorbent assay (ELISA) to distinguish between blood from children and adults in the mosquito blood meal was examined using the alpha 1 chain of the aminopropeptide of human procollagen type I (PINP) as antigenic marker. Rabbit anti-human PINP (alpha 1) antibody was used as catching antibody, and either normal serum from 288 African and 58 Caucasian children and adults, or blood meals from 93 fed Aedes aegypti, were examined. PINP in excess of 40 optical density units (ODU) was detected in all children aged 0-13 years, whereas adults aged 21-77 years had PINP levels less than 25 ODU. In the transitional age group (14-20 years), the PINP levels ranged from 1 to 166 ODU. The PINP levels in 95% of the mosquito blood meals obtained from children exceeded the control levels, using 13 ODU as a cut-off value, whereas none of the blood meals from adults exceeded 13 ODU. The PINP levels in the mosquito blood meals were constant 1 and 8 h after ingestion, but they had decreased significantly after 16-19 h. Our data suggest that the test can be used to identify host preferences in studies of mosquitoes collected within 16 h after the blood meal. A field evaluation is necessary to determine the potential of the antigenic marker PINP as a tool in the identification of mosquito host preference.

Adolescent↗
PubMed1993

Monitoring of veno-occlusive disease after bone marrow transplantation by serum aminopropeptide of type III procollagen.

Differential diagnosis of hepatic complications after bone marrow transplantation (BMT) is often difficult. To assess whether serum concentrations of the aminopropeptide of type III procollagen (PIIINP) could facilitate diagnosis, we measured serum PIIINP, corrected for age by conversion to standard deviation scores (SDS), serially after BMT in 27 children. A preliminary study of 11 patients showed that a PNIIINP-SDS cutoff of 8.0 was an optimum for diagnosis of veno-occlusive disease (VOD). PIIINP-SDS was increased above cut-off 1-25 days before the onset of clinical signs in the 12 patients (4 from the preliminary group, the others from a group of 16 studied prospectively) who developed VOD, with subsequent changes in PIIINP-SDS mirroring the course of VOD. By contrast, PIIINP-SDS remained below cut-off in all other patients, including 7 with liver graft-versus-host disease and 3 with drug hepatotoxicity. PIIINP-SDS values greater than 8.0 predict, diagnose, and monitor VOD after BMT.

Bone Marrow Transplantation↗
PubMed1993

Comparison of serum procollagen III peptide concentrations and PGA index for assessment of hepatic fibrosis.

In early hepatic fibrosis, increased amounts of type III collagen are deposited. Persistently high serum concentrations of aminoterminal type III procollagen propeptide (PIIIP) correlate with the activity of the fibrogenic process. Another index for the detection of fibrosis, the PGA index, combines the prothrombin time, gamma-glutamyl transpeptidase activity, and serum apolipoprotein A1 concentration (the latter falls with progressive fibrosis). We compared PIIIP measurements and PGA index in patients with various histological forms of alcoholic liver disease (104), primary biliary cirrhosis (38), and chronic B virus hepatitis (27), and in healthy age-matched controls (30). The ability of each test to identify correctly patients with fibrosis or cirrhosis was assessed with receiver operating curves. The PGA index was much higher in all groups of patients with alcoholic liver disease than in controls (p < 0.0001). PIIIP concentrations were also substantially higher than in controls (p < 0.05 for fatty liver, p < 0.0001 for all other groups), especially in the group with alcoholic hepatitis and cirrhosis. For the detection of cirrhosis the PGA was 91% sensitive and 81% specific and the PIIIP concentration was 94% sensitive and 81% specific. The two tests combined had 85% sensitivity, but 93% specificity. Among patients with primary biliary cirrhosis, both PGA index and PIIIP concentration correlated well with the severity of the disease, determined by the Mayo score (r = 0.72 and 0.66 respectively). The combined tests were 96% sensitive for the detection of fibrosis. All patients with chronic B virus hepatitis had raised PGA and PIIIP values in comparison with controls (p < 0.0001) but there were no differences between subgroups. Substantially raised PIIIP concentrations thus identify the subgroup of alcoholic patients with both hepatitis and cirrhosis. The combination of PGA index and PIIIP concentration may be useful for targeting treatment with antifibrotic drugs and to reduce the need for liver biopsy.

Apolipoprotein A-I↗
PubMed1994

Serum levels of type III procollagen peptide and peripheral vascular disease in diabetic patients.

The aim of this study was to assess the possible relationship between serum levels of Type III procollagen peptide (PIIINP) and peripheral vascular disease (PVD) in diabetic patients. Ninety Type 2 diabetic patients being treated with sulfonylureas, and 37 non-diabetic subjects were studied using Doppler ultrasound. After an overnight fast, blood was taken for PIIINP, glucose, glucosylated hemoglobin (HbA1), C-peptide, and lipids. Data were analysed according to the non-paired Student's t-test and the correlation coefficient, after log transformation. PIIINP levels were significantly elevated in diabetics with PVD (n = 44), 4.3 micrograms/l (2.4-7.6, 95% confidence limits) compared with controls 3.1 micrograms/l (1.9-4.9), P < 0.001, and with diabetics without PVD (n = 46), 3.1 micrograms/l (1.9-5.0), P < 0.001. No correlation was found between PIIINP and HbA1, glucose, C-peptide, age or duration of diabetes. We conclude that PIIINP levels are elevated in Type 2 diabetics with PVD. It may reflect an increase in collagen deposition in the large arteries that accompanies the development of macroangiopathy.

Diabetes Mellitus, Type 2↗
PubMed1989

Hepatic and renal extraction of circulating type III procollagen amino-terminal propeptide and hyaluronan in pig.

Hepatic and renal clearance of the amino-terminal propeptide of type III procollagen (PIIINP) and of the glycosaminoglycan, hyaluronan (HA) were investigated in a catheterization study of seven healthy anesthetized pigs. Two assays were used, in order to distinguish between the metabolism of different PIIINP-related antigens. One was the PIIINP RIA Kit, which measures the intact propeptide. The other was the PIIINP Fab assay, in which the antibody has an equal affinity to the intact propeptide and to smaller fragments, of which the latter constitutes most of the antigenic activity in serum. Hepatic and gastrointestinal extraction were evaluated from measurements of serum concentrations in the artery, the portal vein and the hepatic vein. We found a significant hepatic extraction of the intact propeptide (extraction ratio 0.14) and of HA (extraction ratio 0.23), but not of smaller PIIINP fragments. No gastrointestinal extraction of any of the tested substances could be demonstrated. Only smaller PIIINP fragments (such as the col 1 fragment) were extracted by the kidneys (the extraction ratio in the PIIINP Fab assay was 0.19). The renal extraction ratio of HA was 0.14. The amounts of PIIINP fragments and of HA extracted by the kidneys were 50- and 3-times the amounts found in urine, respectively, indicating that the col 1 fragment and HA are degraded in the kidneys in addition to urinary excretion. Our results suggest a dynamic turnover of connective tissue-related components with a fast catabolism of circulating components in liver and kidneys.

Animals↗
PubMed1989

Is measurement of type III procollagen amino propeptide useful in primary biliary cirrhosis?

We have examined the value of serum type III procollagen amino propeptide (PIIINP) measurement both in evaluation of disease activity and in estimation of prognosis in primary biliary cirrhosis (PBC). 55 paired sera from 32 PBC patients not receiving treatment known to affect PIIINP levels not with non-hepatic inflammatory conditions were used to estimate serum PIIINP by radioimmunoassay. Significant correlations were found between serum PIIINP and serum albumin (P less than 0.001), bilirubin (P less than 0.002) and aspartate transaminase (P = 0.01). The mean serum PIIINP level rose with advancing histological stage (P less than 0.001). In 18 patients in whom more than 1 serum was assayed (mean follow-up 42 months) PIIINP often fell, particularly in patients with established cirrhosis and advanced disease. The independent prognostic value of PIIINP was examined using Cox's proportional hazards model with three other prognostic co-variables (bilirubin, albumin, patient age). Stepwise regression analysis selected albumin (P less than 0.001) and bilirubin (P = 0.002) as the most important prognostic factors. PIIINP did not give independent prognostic information. We conclude that PIIINP is another marker of disease activity in PBC which confers no benefit over existing conventional measurements in routine management of this disease.

Adult↗
PubMed1989

Liver collagen mRNA and serum amino-terminal peptide of type III procollagen (PIIINP) levels in patients with alcoholic liver disease.

We have investigated the alpha 1 (I), alpha 2 (I) and alpha 1 (III) liver collagen mRNA levels in 38 patients with alcoholic liver disease. The patients were divided into 3 groups according to the severity of their liver disease. Liver collagen mRNA levels were estimated by densitometric analysis after hybridization with the corresponding cDNA. Serum amino-terminal peptide of type III procollagen (PIIINP) was determined by radioimmunoassay in 30 patients. The results indicated that there was no increase but rather a decrease in the liver alpha 1 (I), alpha 2 (I) and alpha 1 (III) collagen mRNA in patients with the most severe liver lesions as compared to those with minimal changes. This decrease was significant for alpha 2 (I) and alpha 1 (III) cDNA probes. In contrast, serum PIIINP levels showed a positive correlation with the severity of the disease. Thus this study indicates that collagen accumulation in the liver as well as elevation of the serum PIIINP during the development of alcoholic liver disease probably reflects posttranscriptional events in collagen synthesis.

Collagen↗
PubMed1991

Predictive value of serum procollagen-III-peptide for the survival of patients with cirrhosis.

The value of the aminoterminal procollagen-III-peptide (P-III-P) in predicting death or survival was evaluated in a group of 43 patients with proven postnecrotic or alcoholic cirrhosis. Patients were followed-up prospectively for 2 years. The prognostic value of P-III-P was compared with the Child classification, fasting and postprandial serum bile acids, and standard laboratory tests such as bilirubin, prothrombin index, pseudocholinesterase, albumin, GOT, GPT, gamma-GT, and clinical findings such as ascites, encephalopathy (assessed with the number connection test = NCT), and nutritional status. Between patients who died and those who survived the following 2 years, there were significant differences in the following parameters at the time of inclusion in the study: encephalopathy judged by NCT (p = 0.001), serum albumin (p = 0.0012), postprandial serum bile acids (p = 0.0024), fasting serum bile acids (p = 0.0025), pseudocholinesterase (p = 0.0044), GOT (p = 0.015), bilirubin (p = 0.016), and prothrombin index (p = 0.01). None of the other parameters investigated, including SP-III-P (p = 0.46), revealed any statistically significant differences between patients who died and survivors. The prognostic significance of laboratory tests and recorded clinical findings was evaluated, either alone or in combination with life-table analysis using the Cox model. SP-III-P, alone or in combination with other parameters, failed to improve prediction of mortality in patients with cirrhosis. In comparison to the Child classification (p = 0.0004) the combination of NCT and postprandial serum bile acids showed a similar ability (p = 0.0003) to predict patient survival.

Biomarkers↗
PubMed1992

Serial determination of type III procollagen amino propeptide serum levels in patients with histologically progressive and non-progressive primary biliary cirrhosis.

We examined the value of serum procollagen III amino propeptide (PIIIP) for predicting the histological progression of primary biliary cirrhosis (PBC). Serial PIIIP measurements were obtained for nine patients with histologically progressive PBC and nine patients with histologically stable early disease, assessed by repeated liver biopsies and followed for up to 13 years. The means of the follow-up PIIIP concentrations were elevated in 39% of the cases; moreover, PIIIP levels were elevated at least once during follow-up in 72% of the cases. Mean follow-up PIIIP concentrations did not differ significantly between progressive and non-progressive patients. In addition, in the progressive group, histological progression was not reflected by PIIIP levels. No difference was found between the serum PIIIP levels corresponding to the histological stages I, II and III. The individual coefficients of the correlation between serum PIIIP and biochemical variables (bilirubin, alkaline phosphatase, ASAT, albumin) and histology showed a wide distribution without a consistent trend towards positive or negative. Treatment with cyclosporin A or cyclosporin A combined with prednisone did not influence serum PIIIP levels. Treatment with penicillamine combined with prednisone, however, resulted in a significant decrease in PIIIP concentrations (p less than 0.05). We conclude that serum PIIIP measurements are of no value for predicting the histological progression of PBC.

Adult↗
PubMed1975

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↗
PubMed1984

The structure of the carbohydrate units of the carboxyl-terminal peptide of procollagen as elucidated by 500 MHz 1H-NMR spectroscopy.

The oligosaccharides of chick embryo type I procollagen were isolated from carboxyl-terminal propeptide fragment by exhaustive digestion with papain and pronase, and then purified as a mixture of glycopeptides. The structures of the oligosaccharides were established by high-resolution 1H-NMR spectroscopy and found to be a mixture with respect to the non-reducing terminal residues as shown below: (formula; see text) The percentages refer to the relative amount of those mannose residues present in the mixture. The data suggest that the oligosaccharides are a microheterogeneous mixture of high-mannose type glycans containing between six and nine mannose residues per carbohydrate unit. Such carbohydrate chains, although not uncommon for glycoproteins, had never been found before for collagen or collagen-related compounds.

Amino Acid Sequence↗
PubMed1991

Procollagen-III in serum, plasminogen activation and fibronectin in bronchoalveolar lavage fluid during and following irradiation of human lung.

In the search for predictors of late radiation-induced lung injury we studied procollagen type III peptide concentration (P-III-P) in serum as well as fibronectin and plasminogen activation in bronchoalveolar lavage (BAL) fluid during and following irradiation of human lung. The patients received either high-dose hemithorax irradiation for pleural mesothelioma (11 patients) or high-dose irradiation with individually shaped fields for non-small cell lung cancer (12 patients). The severity of radiation fibrosis was assessed clinically from CT scans 6 months and 12 months after treatment. Four scores were used: severe, moderate, mild, or normal. Radiological lung injury varied from "severe" (9 patients) to near absence of injury-"normal" (6 patients). Serum levels of P-III-P, when measured weekly during the 5-week period of radiotherapy or at several time-points after treatment, did not show consistent changes, nor did the levels correlate with the score for radiation fibrosis as assessed by CT scanning. Changes in fibronectin levels or in markers of plasminogen activation in BAL fluid did not correlate with the development of late lung injury. The levels of BAL fluid plasmin and plasminogen activator as assessed zymographically, but not the free net enzyme values, showed a tendency to be elevated in patients with severe radiation-induced lung injury, suggesting a possible role for inhibitors of the plasminogen activation cascade in the process of radiation-induced lung injury.

Adult↗
PubMed1990

Clinical and prognostic value of serum procollagen levels in chronic alcoholic liver disease.

Liver fibrogenesis involves the synthesis of collagen fibrils and proteoglycans by various types of liver cells, including Ito cells, transitional cells, myofibroblasts and hepatocytes. Synthesis of collagen fibrils follows a complex metabolic pathway with intermediate products such as type III procollagen (III-PC). Serum levels of III-PC may reflect the activity of the fibrogenetic process. We analysed the relationship between the serum levels of III-PC (N-terminal peptide) and diverse clinical, biochemical and histological parameters of 77 alcoholic patients (27 cirrhotics), comparing them with those of 15 age- and sex-matched controls. A highly significant difference was obtained between controls and patients (P less than 0.0001), but no differences were observed between cirrhotics and non-cirrhotics. Serum III-PC significantly correlated with clinical and biochemical data of liver function derangement (prothrombin activity, serum albumin, bilirubin, gynecomastia, ascites, encephalopathy, edema, splenomegaly); with the duration of ethanol addiction and with MCV. Sixty patients were followed up for a period ranging between 3 and 1056 days (mean = 356 days); 9 of them died. Patients with III-PC levels above 38 ng/ml had a significantly higher mortality (P = 0.006) than those with levels under 38 (log rank test). Thus, serum III-PC may be a useful tool in the clinical evaluation and prognostic assessment of patients with chronic alcoholic liver disease.

Adult↗
PubMed1989

Cloning and analysis of the 5' portion of the human type-III procollagen gene (COL3A1).

We have isolated overlapping clones containing the 5'-terminal portion of the human pro-alpha 1(III) collagen gene (COL3A1). This has enabled us to extend our previous studies and thus generate a restriction map of nearly 64 kb of DNA encompassing all of COL3A1 and more than 20 kb of flanking sequences. Aside from the complete nucleotide and amino acid sequences of type-III N-pre-propeptide, this study has established the number of the corresponding exons, whose relative organization deviates from the pattern observed in the analogous regions of type-I procollagen genes, COL1A1 and COL1A2. Moreover, we have sequenced 1628 bp of the 5'-flanking region of COL3A1, from the transcription start point (tsp) to an AluI repetitive element. Pairwise comparison with the analogous segment of the mouse gene has showed 78% sequence similarity in nearly 270 bp immediately preceding the tsp and including the TATA element and a presumptive NF-1 binding site. Relatively close to the tsp, but upstream from the region of homology with the murine gene, a potential AP-1 binding site has also been identified.

Amino Acid Sequence↗
PubMed1990

Completion of the intron-exon structure of the gene for human type II procollagen (COL2A1): variations in the nucleotide sequences of the alleles from three chromosomes.

A new procedure for preparing cosmid libraries was used to isolate three alleles for the human gene for type II procollagen (COL2A1). Over 20,000 bp of one allele were completely sequenced and over 10,000 bp of the two other alleles were sequenced. The data located and defined 26 exons and introns of the gene not previously analyzed. The results completed the structure of the gene except for the newly discovered exon 2A that undergoes alternative splicing (Ryan et al., 1990, Trans. Ann. Meet. Orthop. Res. Soc. 15:65). As a result, it is the most completely known structure of a gene for a human fibrillar collagen. The results confirm the previous impression that exon sizes are highly conserved among the genes for the three major fibrillar collagens. Comparison of clones from the three alleles defined five neutral variations in coding sequences and seven variations in the intron that also are probably neutral variations. The normal sequences and the variations in sequences will be important for identifying different alleles and haplotypes of the gene and for the analysis of genetic mutations in the gene that cause diseases of cartilage such as chondrodysplasias and osteoarthritis.

Alleles↗