PICP) And The Aminoterminal Propeptide Of Type III Procollagen Research Articles

Synthesis of collagen types I and III in reincised wounds in humans

The problem of the biochemical quantification of long term human wound healing was approached by measuring collagen synthesis in reincisions using specific radioimmunoassays for the wound fluid concentrations of the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP). First-day wound fluid PICP concentration after reincising a 3 week old scar was 25 times higher than the mean value in 20 reference standard incisions but scars older than 3 months did not show this difference. Wound fluid taken in subsequent days demonstrated that the initial acceleration of synthesis disappeared by the fourth day. When wound fluid PIIINP was assessed, high concentrations were found in reincisions of wounds for up to 5 months after the previous operation. The acceleration was also lost more slowly during the first postoperative week. The duration of a high rate of type I collagen synthesis compares well with studies in experimental wounds which show increased gain of strength if they are made not more than 6 weeks after previous surgery. The longer activity of the metabolism of type III collagen related antigens could reflect their function in the regulation of collagen fibril formation.

Rapid induction of meningeal collagen synthesis in the cerebral cisternal and ventricular compartments after subarachnoid hemorrhage.

Procollagen propeptides in the lumbar CSF increase after subarachnoid hemorrhage (SAH), and elevated concentrations have been detected as early as on day 8. We studied here the timing and localization of the induction of meningeal collagen synthesis during the first week after SAH by analysing cisternal and ventricular CSF samples. We obtained 29 cisternal and 10 ventricular CSF samples at operation from patients with SAH between days 1 and 9 after onset. The carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) were measured using radio-immunoassays. The concentrations of PICP and PIIINP in the cisternal CSF were elevated as early as on day 2 after SAH. PICP increased in a sigmoidal fashion (R2 = 0.39, p < 0.001), while PIIINP increased linearly (R2 = 0.28, p = 0.003) and was approximately 3-fold higher on day 9 than initially. PICP was twice as high (p = 0.02) in the cisternal than in the ventricular CSF after SAH and PIIINP was 4-times higher (p = 0.007). Interestingly, the concentrations were similar in a patient with intraventricular bleeding. The cisternal compartment contributed to the propeptides in the CSF more than did the ventricular compartment, but the latter also appeared to have a definite potential for fibroproliferative reaction. Meningeal collagen synthesis was induced rapidly within the first few days after SAH suggesting that therapeutic attempts to inhibit the fibroproliferative reaction should be started as early as possible.

Detection of meningeal fibrosis after subarachnoid haemorrhage by assaying procollagen propeptides in cerebrospinal fluid

OBJECTIVETo study whether meningeal collagen synthesis under normal conditions is reflected in the CSF and whether a meningeal fibroproliferative reaction or fibrosis after subarachnoid haemorrhage can be detected by measuring...

Responses of Type I and Type III Collagen Synthesis after Replacement of the Hip Joint

Liberation of the carboxy-terminal propeptide of type I procollagen (PICP) and the amino-terminal propeptide of type III procollagen (PIIINP) into body fluids reflects synthesis of the respective collagen types. Here, we followed PICP and PIIINP in serum with specific radioimmunoassays after hip surgery. Preoperative median of S-PICP was 112 μg/liter (range 87 to 154, n = 9), the 1-day median being 58 μg/liter (33 to 79). The corresponding medians for S-PIIINP were 4.4 μg/liter (3.5 to 7.0) and 3.3 μg/liter (2.0 to 3.5). The medians reached their maximums 14 days after surgery, 172 μg/liter (122 to 440) for S-PICP and 12.4 μg/liter (8.0 to 15.4) for S-PIIINP, after which the preoperative values were slowly approached over several months. Comparable results were found in a greater sample ( n = 50). Our results indicate that the synthesis of structural collagen is inhibited immediately after surgery, but the inhibition is soon overcome by active collagen synthesis at the site of trauma. Collagen metabolism remains activated for several months after surgery.

Markers of type I and type III collagen synthesis in serum as indicators of tissue growth during pregnancy.

The concentrations of the carboxy-terminal propeptide of type I procollagen (PICP) and the amino-terminal propeptide of type III procollagen (PIIINP) in serum were followed prospectively as indicators of synthesis of the respective collagens in 266 healthy primiparas during the second and third trimesters of pregnancy. The PIIINP concentration increased 2-fold during the third trimester; the median value was 10.0 micrograms/L at gestational week 40, with a range from 4.6-32.7 micrograms/L (reference interval for nonpregnant women, 1.7-4.2 micrograms/L). A significant increase also took place in the PICP concentration. The frequency distributions of the two parameters were near normal at week 26. They started to broaden out at week 32 and were wide at week 38. In severe preeclampsia, PIIINP tended to increase more than in normal pregnancies of the same duration. The increase in PIIINP correlated significantly with maternal weight gain and the birth weight of the infant, but not with other parameters related to pregnancy or delivery. At gestational week 38, there was a significant correlation between the circulating concentrations of insulin-like growth factor-I and PIIINP or PICP, but not between human placental lactogen and PICP, and only a weak association between human placental lactogen and PIIINP. This suggests that insulin-like growth factor-I is involved in the regulation of type I and type III collagen synthesis during pregnancy.

Collagen synthesis in intact skin is suppressed during wound healing.

Simultaneous monitoring of total collagen synthesis as well as synthesis in intact skin and in the wound to verify the higher priority of wound healing after surgery. Synthesis of acute phase proteins is stimulated by surgical trauma. At the same time, production of albumin is inhibited and there is a net catabolism of skeletal muscle proteins. Similarly, the authors have found a transient inhibition of total collagen synthesis after surgery. The authors hypothesized a lower priority in synthesis of structural and peripheral collagen for the benefit of wound healing. The concentrations of the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) were measured in suction blister fluid of intact skin and in wound fluid in ten surgical patients. PICP and PIIINP concentrations in serum were also measured. Specific radioimmunoassays were used. In peripheral skin, the median preoperative concentrations of PICP and PIIINP were 228 and 140 micrograms/L, respectively. On postoperative days 1, 2, 4 and 7, the median concentration of PICP was 145 (p = 0.01, Wilcoxon signed rank sum test), 102 (0.02), 159 (0.03), and 152 (0.06) micrograms/L, respectively. The postoperative medians of PIIINP were 68 (p = 0.17), 76 (0.04), 66 (0.06), and 56 (0.03) micrograms/L, respectively. At the same time, collagen synthesis in the wound increased dramatically from the second day on. After an initial decrease, propeptide concentrations in serum gradually increased from the fourth day on. Collagen synthesis is regulated for the benefit of the wound during the acute phase response.

Synthesis of Type I Collagen in Healing Wounds in Humans

To quantify wound healing in surgical patients, samples of wound fluid were collected through a silicone rubber tube for 7 postoperative days and their concentrations of the carboxyterminal propeptide of type I procollagen (PICP) and the aminoterminal propeptide of type III procollagen (PIIINP) were measured with specific radioimmunoassays. The mean concentration of PICP in would fluid on day 1 was 207 +/- 92 (SD) micrograms/L, and on day 2 908 +/- 469 micrograms/L (p less than 0.001, signed rank test). On day 7, the mean concentration reached was 380 times higher than that of day 1 (79,330 +/- 54,151 micrograms/L). Only one peak of PICP antigenicity, corresponding to the intact propeptide as set free during synthesis of type I procollagen, was detected on Sephacryl S-300 gel filtration analysis of wound fluid samples. The mean concentration of PIIINP was 70 +/- 61 micrograms/L on day 1, 86 +/- 88 micrograms/L on day 2, and 180 +/- 129 micrograms/L on day 3 (p less than 0.001 when compared with day 1). Finally on day 7, a 250-fold concentration (17,812 +/- 9839 micrograms/L), compared with day 1, was reached. Methods described in the present paper allow separate and repetitive quantification of the synthesis of both type I and type III procollagen during human wound healing.