The serum concentrations of the aminoterminal propeptide of procollagen type III and the hepatic content of mRNA for the alpha 1 chain of procollagen type III in carbon tetrachloride-induced rat liver fibrogenesis.

Serum concentrations of the aminoterminal propeptide of procollagen type III (PIIIP) are elevated in fibrogenic diseases of the liver, but the mechanism of elevation is not fully understood. To investigate the mechanism, we compared serum concentrations of PIIIP with total liver content of mRNA for the pro alpha 1 (III) chain, in rats with carbon tetrachloride (CCl4)-induced liver fibrosis. Adult male rats received CCl4 in mineral oil twice weekly for 8 weeks and were compared with age-matched controls. Serum concentrations of PIIIP were measured by a specific radioimmunoassay; molecular sizes of PIIIP in serum were also determined. Pro alpha 1 (III) mRNA content in the liver was quantitated by RNA slot-blot hybridization and chemical measurement of total hepatic RNA content. Total collagen content of the liver was estimated by hydroxyproline measurement. All CCl4-treated animals had septal fibrosis after 4 weeks, and evidence of cirrhosis (regenerative nodules, ascites) was seen after 7 weeks of treatment. Serum concentrations of PIIIP and pro alpha 1 (III) mRNA content in the liver were correlated well until cirrhosis has established. They increased simultaneously after 3 weeks of treatment, 1 week before any elevation of hepatic hydroxyproline could be detected. After cirrhosis has established, pro alpha 1 (III) mRNA content in the liver decreased markedly, but serum PIIIP levels continued to be elevated. Hepatic hydroxyproline plateaued after 5 weeks. The molecular sizes of serum PIIIP indicate the release of intact native procollagen peptide during the development of cirrhosis. In conclusion, at least in CCl4-induced liver fibrosis in the rats, serum PIIIP levels can be used as a fibrogenic marker for the period progressing to cirrhosis. But the use of the serum PIIIP levels in cirrhosis seems to be limited by factors other than liver fibrogenesis.     

Evaluation of hepatic fibrosis by serum proline and amino-terminal type III procollagen peptide levels in alcoholic patients

In patients with alcoholic liver disease, serum proline and amino-terminal type III procollagen peptide levels were evaluated as a marker of hepatic fibrosis. Thirty-one patients with alcoholic liver disease (2 with nonspecific change, 3 with alcoholic hepatitis, 17 with hepatic fibrosis without cirrhosis, and 9 with cirrhosis) and 15 controls were investigated. Hepatic fibrosis was estimated in each liver biopsy specimen by morphometric analysis, and the ratio of fibrotic change to total area (AREA-F) was calculated by morphometric analysis. In patients with hepatic fibrosis, serum proline levels and routine liver function tests were not significantly correlated to AREA-F value, while serum peptide levels showed a significant positive correlation to AREA-F value (r=0.733,P<0.001). These results suggest that the determination of serum amino-terminal type III procollagen peptide level may serve as a good marker for the diagnosis of liver fibrosis in the alcoholic.This study was supported in part by grants 57570273 and 59480207 from the Japanese Ministry of Education, Science and Culture.     

The serum concentrations of the aminoterminal propeptide of procollagen type III and the hepatic content of mRNA for the α1 chain of procollagen type III in carbon tetrachloride-induced rat liver fibrogenesis

Serum concentrations of the aminoterminal propeptide of procollagen type III (PIIIP) are elevated in fibrogenic diseases of the liver, but the mechanism of elevation is not fully understood. To investigate the mechanism, we compared serum concentrations of PIIIP with total liver content of mRNA for the pro α1 (III) chain, in rats with carbon tetrachloride (CCl₄)-induced liver fibrosis. Adult male rats received CCl₄ in mineral oil twice weekly for 8 weeks and were compared with age-matched controls. Serum concentrations of PIIIP were measured by a specific radioimmunoassay; molecular sizes of PIIIP in serum were also determined. Pro α1 (III) mRNA content in the liver was quantitated by RNA slot-blot hybridization and chemical measurement of total hepatic RNA content. Total collagen content of the liver was estimated by hydroxyproline measurement. All CCl₄-treated animals had septal fibrosis after 4 weeks, and evidence of cirrhosis (regenerative nodules, ascites) was seen after 7 weeks of treatment. Serum concentrations of PIIIP and pro α1 (III) mRNA content in the liver were correlated well until cirrhosis has established. They increased simultaneously after 3 weeks of treatment, 1 week before any elevation of hepatic hydroxyproline could be detected. After cirrhosis has established, pro αl (III) mRNA content in the liver decreased markedly, but serum PIIIP levels continued to be elevated. Hepatic hydroxyproline plateaued after 5 weeks. The molecular sizes of serum PIIIP indicate the release of intact native procollagen peptide during the development of cirrhosis. In conclusion, at least in CCl₄-induced liver fibrosis in the rats, serum PIIIP levels can be used as a fibrogenic marker for the period progressing to cirrhosis. But the use of the serum PIIIP levels in cirrhosis seems to be limited by factors other than liver fibrogenesis.     

Is determination of serum N-terminal procollagen type III peptide (sPIIIP) a marker of hepatic fibrosis?

Serum N-terminal procollagen type III peptide (sPIIIP) levels were evaluated in 58 patients affected by chronic liver disease, in order to assess the usefulness of sPIIIP as a marker of hepatic fibrosis. In 45 patients sPIIIP was also correlated to liver histology; biopsies were scored by two of the authors, without knowledge of diagnosis. Compared to normal controls, sPIIIP concentration was found to be significantly elevated in chronic active hepatitis (CAH) and in cirrhosis, but not in fatty liver. Patients affected by chronic persistent hepatitis (CPH) had values of sPIIIP higher than normal in four of 11 cases considered. A close correlation was found between sPIIIP values and histological parameters of inflammation, necrosis, and degeneration, while the relationship between sPIIIP levels and fibrosis was weaker. These data suggest that sPIIIP determination may reflect the extent of inflammatory changes in the liver; but it cannot be considered a reliable index of hepatic fibrosis.     

Serum type IV collagen in various liver diseases in comparison with serum 7S collagen,laminin, and type III procollagen peptide

The clinical significance of the immunoreactive triple helical domain of type IV collagen in serum was evaluated in 73 healthy controls and 161 patients with various biopsy-proven liver diseases. Although serum levels of type III procollagen peptide were increased in all liver diseases, those of type IV collagen, 7S collagen, and laminin were principally increased in chronic liver diseases associated with hepatic fibrogenesis/fibrosis. In both non-alcoholic and alcoholic liver diseases, 7S collagen was increased in serum, while type IV collagen and laminin in serum were particularly increased in alcoholic liver diseases and in hepatocellular carcinoma, in which latter the sensitivity was greater for type IV collagen than for laminin. Gel filtration analysis in Sephacryl S-400 revealed type IV collagen in serum to be a single molecular form with a molecular weight that correspond to type IV collagen, whereas 7S collagen was recognized as several heterogeneous macromolecules. These findings indicate that serum type IV collagen is derived from the type IV protocollagen pool, and is a sensitive marker for the fibrogenetic process in hepatic basement membranes.     

Serum levels of aminoterminal type III procollagen peptide in normal subjects and hepatic fibrosis

Serum levels of aminoterminal type III procollagen peptide in normal subjects were determined by radioimmunoassay. The levels of the peptide markedly increase in infants and gradually decrease with age in childhood. The peptide increases again in prepubertal children and then decreases through adulthood. These findings suggest that increased levels of the peptide reflect accelerated collagen synthesis in the human body. Comparison of serum levels of the peptide with the degree of hepatic fibrosis revealed that the peptide increased in parallel with the progress of hepatic fibrosis.     

Serum concentration of the aminoterminal procollagen type III peptide in the rat reflects early formation of connective tissue in experimental liver cirrhosis

A specific and sensitive radioimmunoassay for the rat aminoterminal procollagen type III peptide (PIIIP) was developed which allowed easy and sequential measurement of this peptide in the serum of individual animals. PIIIP in sera of 1-week-old rats was high (60 +/- 15.4 ng, 1 SD) falling to 15.7 +/- 4.3 ng/ml (1 SD) at 7 weeks and 6.7 +/- 2.6 ng/ml (1 SD) at 12 weeks of age. Adult animals (above 6 months of age) showed serum PIIIP levels in the narrow range of 2.5 +/- 2.33 ng/ml (2.5 SD). CCl4-induced liver damage in adult rats produced an elevated serum PIIIP (median 9.1; range 2.6-45.2 ng/ml) already after 2 weeks, rising to a mean of 33.8 ng/ml (range 22.0-47 ng/ml) after 6 weeks of continued CCl4-intoxication. In the same animals at 6 weeks, hepatic hydroxyproline was almost 5 times higher in the CCl4-group (mean 493.2; range 343.1-582.3 micrograms/100 mg dry weight) when compared with controls (109 +/- 14 micrograms/100 mg dry weight, 1 SD). These results are in complete analogy to those reported for PIIIP in sera of growing children, healthy human adults and patients with fibrogenic liver disease. Elevated serum PIIIP in rats with experimental liver fibrosis predicts the deposition of excess hepatic collagen. This novel serum test allows, for the first time, to assess altered PIIIP metabolism and hepatic fibrogenesis in individual animals as early as 2 weeks after the start of the experiment. It also reflects growth-related changes of type III collagen metabolism.     

Higher levels of serum aminoterminal type III procollagen peptide, and laminin in alcoholic than in nonalcoholic cirrhosis of equal severity.

In vitro models have shown that metabolites of ethanol (acetaldehyde and lactate) stimulate collagen synthesis, thereby, suggesting that they may be important as fibrogenic mediators. The relevance of these findings for fibrogenesis in the human liver in vivo, however, has not as yet been demonstrated. Serum markers for collagen (PIIINP, using radioimmunoassays employing polyclonal antibodies and Fab-fragments (PIIINP-Fab), respectively) and basement membrane (laminin) metabolism were therefore investigated in 25 alcoholic cirrhotics (Pugh-Score: 6.7 +/- 1.9 S.D.) and in 19 comparable nonalcoholic cirrhotics (Pugh-Score: 6.3 +/- 1.5, n.s.) with only slight evidence for inflammation: GOT 28 +/- 22 vs. 24 +/- 21 U/l; GPT 24 +/- 23 vs. 31 +/- 28 U/l; gamma-globulins 24 +/- 8 vs. 22 +/- 5%, respectively (all n.s.). Severity of the disease was assessed by quantitative liver function tests. Levels of PIIINP, PIIINP-Fab and laminin measured by RIA were 21 +/- 19 micrograms/l, 90 +/- 42 micrograms/l and 2.5 +/- 0.8 U/ml in alcoholic cirrhosis and 10 +/- 6 micrograms/l, 61 +/- 10 micrograms/l and 1.9 +/- 0.4 U/ml in nonalcoholic cirrhosis, respectively (all p less than 0.01). Differences on PIIINP and PIIINP-Fab remained significant even after accurate matching for galactose elimination capacity, aminopyrine breath test and hepatic sorbitol clearance. Laminin levels were higher in alcoholic cirrhosis only after matching for the hepatic sorbitol clearance (p less than 0.01). The higher levels of serum markers for collagen and basement membrane metabolism in alcoholic vs. nonalcoholic patients with cirrhosis at equal severity of the disease and with only minimal signs of inflammation may be the clinical reflection of a specific fibrogenic effect of ethanol metabolites.     

The N-terminal propeptide of collagen type III in serum as a prognostic indicator in primary biliary cirrhosis

The serum level of N-terminal propeptide of collagen III (Col 1-3) has received increasing attention as a possible marker of liver fibrosis. Elevated levels have been reported in patients with primary biliary cirrhosis (PBC). We measured Col 1-3 levels in 24 patients with PBC (mean age 56 +/- 8 years) and compared their value as a prognostic marker with serum bilirubin and IgM levels, the aminopyrine demethylating capacity (ABT) and presence of clinical symptoms. Mean observation time was 5.1 +/- 2.7 years. When these parameters and age were evaluated as predictive factors for survival, only bilirubin, Col 1-3 levels and symptom status variables were found to be significant. When tested as explanatory variables for survival in a stepwise linear logistic regression model Col 1-3 was identified as the strongest significant (P less than 0.001) explanatory variable followed by bilirubin (P less than 0.01) whereas the symptom status emerged as a non-significant variable. The results suggest that the serum level of Col 1-3 may be a useful prognostic indicator in PBC, which is independent of the bilirubin level.     

肝硬化child分级与血清Ⅲ型前胶原氨基端肽水平相关性研究

本文对136例肝硬化患者的 child 分级及其血清 PⅢP 水平进行检测分析,结果发现 child A、B、C 各级病人之间 SPⅢP 水平存在着显著性差异,且肝功能状态越差,其血清 PP 水平越高:而同一病人在不同时期肝功能 child 分级不同状态下,其 SPⅢP 水平随着 child 分级评分升高而升高。我们认为:血清 PⅢP 水平在一定程度上可以反映肝硬化患者的综合肝功能状态并对评估其预后有一定的临床意义.     

Biliary excretion of procollagen type III peptide in healthy humans and in patients with alcoholic cirrhosis of the liver

Serum concentrations of procollagen type III peptide are found to be elevated in liver disease and to correlate with fibrosis activity in liver tissue. These elevated serum levels may be due to enhanced synthesis, decreased excretion, or release from deposits of the propeptide in connective tissue. To quantitatively investigate the excretion of procollagen type III peptide, we studied its presence in the bile and urine of 10 healthy controls and 11 patients with alcoholic cirrhosis of the liver. Biliary excretion rates of procollagen propeptide were determined by the duodenal perfusion method. The serum concentrations of procollagen type III peptide were 2.5 +/- 0.5 ng/ml in the healthy controls and 33.6 +/- 6.8 ng/ml in the patients with cirrhosis. Procollagen type III peptide was found in the bile; the healthy controls excreted 0.4 +/- 0.07 nmol/h and the cirrhotics excreted 0.98 +/- 0.27 nmol/h. A fragment of the procollagen propeptide, Col 1, was excreted in urine; the healthy controls excreted 0.25 +/- 0.04 nmol/h, and the cirrhotics excreted 0.11 +/- 0.03 nmol/h. These data demonstrate that the biliary excretion of procollagen type III peptide represents a quantitatively important pathway.     

Is the aminoterminal propeptide of type III procollagen degraded in the liver? A study of type III procollagen peptide in serum during liver transplantation in pigs

The aminoterminal propeptide of type III collagen was monitored in serum during liver transplantation in nine pigs. The aim was to investigate whether removal of the liver causes any changes in the serum concentration of the propeptide. Another connective tissue component, hyaluronan, a glycosaminoglycan known to be degraded in the liver endothelial cells, was also measured. Removal of the liver caused a significant increase in the concentration of the intact propeptide as well as of hyaluronan. Gel filtration confirmed the increase in the amount of intact propeptide. However, another large propeptide-related antigen, eluted near the void volume, appeared in the antigen profile during the anhepatic phase. This peak probably represents the propeptide still attached to the collagen molecule (pN collagen). The findings indicate that the liver is involved in the degradation of the propeptide and of larger propeptide-holding proteins.     

Predictive value of serum aminoterminal type III procollagen peptide levels, serum laminin levels, and liver membrane antibodies for prognosis of chronic hepatitis

Serum concentration of aminoterminal type III procollagen peptide (P3P) and laminin have been shown as serum markers of liver fibrosis. In addition, liver membrane antibody (LMA) is suggested to play a role in the pathogenesis of chronic hepatitis. However, it is not known whether these serum markers are useful to predict the prognosis of chronic hepatitis. To test this, we measured P3P, laminin, and LMA in sera at the time of liver biopsies in 43 patients with chronic hepatitis who had serial liver biopsies more than two times during the 2-81 months (mean 25 months) follow-up period. Serum contents of P3P and laminin were measured by radioimmunoassay. Serum LMA was measured by radioimmunoassay according to the method of Thomas et al. The histological grading of liver fibrosis and of inflammation were scored according to Histology Activity Index by Knodell et al. Among thirty-two patients who had liver biopsies during 12-55 months, 16 patients showed histological progression on their latest liver biopsies compared with the first biopsies (Group 1). At the first biopsies, serum P3P levels were significantly higher in Group 1 than in 16 patients without histological progression (Group 2) (p less than 0.05). However, no difference were observed in serum laminin levels and in serum LMA between the two groups. Serum laminin levels were significantly correlated with the histological scores of fibrosis (comparison chisq = 0.0089, df = 2, p = 0.995584) and inflammation (comparison chisq = 21.4103, df = 4, p = 0.000263), respectively. In addition, serum P3P levels showed no correlation with the histological scores.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum and urinary aminoterminal type III procollagen peptide in progressive systemic sclerosis: relationship to sclerodermal involvement, serum hyaluronan and urinary collagen metabolites

Increased serum values of aminoterminal type III procollagen peptide and hyaluronan (hyaluronate) and enhanced urinary content of hydroxyproline and hydroxylsine containing polypeptides were demonstrated in patients with progressive systemic sclerosis (PSS). The serum propeptide level and the relative urinary excretion of hydroxyproline as polypeptides were related to the extent of cutaneous involvement. Elevated serum propeptide and hyaluronan values were seen in patients who progressed within the following 6 months. Patients with CREST syndrome had normal propeptide values. Reduced renal propeptide clearance is a likely cause of high serum levels of propeptide degradation products demonstrated in PSS. Serum propeptide seems to be a useful novel marker for disease activity and progression in PSS because of its linkage to the actual connective tissue metabolism.     

Serum type III procollagen and basement membrane proteins as noninvasive markers of hepatic pathology in Indian childhood cirrhosis

While serum concentrations of antigens of the aminopropeptide of type III procollagen have been considered as indicators of hepatic pathology in adults, the high concentrations normally found in children during growth may preclude their use in pediatric liver disease. To clarify this and to determine the role of other circulating connective tissue-related substances in children, we have measured serum concentrations of antigens related to aminopropeptide of type III procollagen, the 7S domain of type IV collagen and the P1 fragment of laminin in healthy subjects aged 1 month to 4 years and in children with Indian childhood cirrhosis, a particularly aggressive form of liver disease. In healthy subjects, there was a considerable age variation in serum aminopropeptide of type III procollagen but not in 7S collagen or laminin P1. In Indian childhood cirrhosis, all three serum antigens were increased (p less than 0.001) above the upper limit of normal for age. Both the serum 7S collagen and laminin P1 concentrations showed a significant correlation with the degree of intralobular fibrosis and also with the severity of necrosis and cellular infiltration, suggesting that these serum antigens may be a noninvasive means of assessing and monitoring events associated with hepatic fibrosis in Indian childhood cirrhosis. The raised serum aminopropeptide of type III procollagen in Indian childhood cirrhosis did not correlate with any histological parameter assessed. Gel filtration of serum showed that, in healthy subjects, the predominant antigenic form of aminopropeptide of type III procollagen was a degradation peptide smaller than authentic aminopropeptide of type III procollagen; while in Indian childhood cirrhosis the authentic peptide and a larger degradation peptide predominated.(ABSTRACT TRUNCATED AT 250 WORDS)     

Assays of serum laminin and type III procollagen peptide for monitoring the clinical course of diabetic microangiopathy

Thickening of the capillary basement membrane is a characteristic feature of diabetes and is considered to cause diabetic microangiopathy. Serum levels of both laminin, a glycoprotein in the basement membrane, and type III procollagen peptide (P-III-P) were measured by specific radioimmunoassays according to the methods of Brocks et al. and Rohde et al. respectively and analyzed with regard to diabetic microangiopathy, glycemic control, diabetic duration and treatment. As a result, serum levels of both laminin and P-III-P showed higher values with development of diabetic microangiopathy, suggesting that progressive changes in diabetic microangiopathy occur with synthesis of laminin and P-III-P. Serum laminin and P-III-P appear to be good non-invasive markers for measuring basement membrane metabolism and type III collagen accumulation. High values of serum laminin and P-III-P levels were suspected to be due to improper treatment, using hypoglycemic agents without adherence to the diet regimen.