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Collagen Turnover (collagen + turnover)
Selected AbstractsDifferent estrogen sensitivity of urogenital tissue from women with and without stress urinary incontinence,,NEUROUROLOGY AND URODYNAMICS, Issue 6 2009Lena Edwall Abstract Aims Oral hormone replacement therapy (HRT) based on estradiol-17, (E2), E2 esters or conjugated equine estrogens gives rise to huge amounts of circulating estrone (E1) as a result of the first liver pass. E1 is an estrogen (ER) receptor agonist but has also been reported to act as a partial E2 antagonist in vitro. Our aim was to investigate the influence of circulating estrogens on estrogen sensitivity of urogenital tissue collagen turnover in patients with stress urinary incontinence (SUI) and in urologically healthy women, with and without HRT, in view of possible effects of E1 as a partial E2 antagonist. Methods Markers of collagen turnover, the carboxy-terminal propeptide of type I procollagen (PICP), the carboxy-terminal telopeptide of type I collagen (ICTP) and the amino-terminal propeptide of procollagen III (PIIINP) were assayed in urogenital tissue homogenates and E1 and E2 were analyzed in serum from 54 patients with SUI and 29 urologically healthy women. Results In the total control group only a significant positive correlation was found between E2 and T-PICP. Lowering the upper serum E1 limit resulted in significant positive correlations also between E2 and T-PIIINP and finally also between E2 and T-ICTP. This pattern was found also in subgroups of post- and premenopausal controls. No association between serum E2 and collagen turnover markers and no effects of lowering the upper serum E1 limit was found in the total and postmenopausal SUI patients, while the correlation pattern in premenopausal SUI patients showed some resemblance to that in the controls. Conclusion At physiological E1 levels E2 increases collagen turnover in urogenital tissue in urologically healthy women but not in women with SUI in general; however, there was a certain effect of E2 in premenopausal but not in postmenopausal SUI patients. Urogenital tissue in SUI patients and in urologically healthy women may differ in estrogen sensitivty and in SUI patients this difference may be related to menopause. Circulating E1, which is present in huge amounts during oral HRT, may act as an estrogen receptor agonist as well as a partial E2 antagonist also in humans in vivo. Neurourol. Urodyn. 28:516,520, 2009. © 2009 Wiley-Liss, Inc. [source] Keloid-derived fibroblasts show increased secretion of factors involved in collagen turnover and depend on matrix metalloproteinase for migrationBRITISH JOURNAL OF DERMATOLOGY, Issue 2 2005M. Fujiwara Summary Background, ,A keloid is a specific skin lesion that expands beyond the boundaries of the original injury as it heals. Histologically, it is characterized by the excessive accumulation of collagen. However, the reasons for the expansion and the invasive nature of keloids remain unknown. Objectives, We evaluated collagen degradation and migration by cultured keloid fibroblasts based on the assumption that these variables were of functional relevance to the expanding and invasive nature of keloid lesions. Methods, Collagen production was investigated by the detection of type 1 collagen (procollagen type 1C peptide: P1P). Matrix metalloproteinase (MMP)-1 (interstitial collagenase) and MMP-2 (gelatinase-A), were investigated as elements of the collagen degradation system. Enzyme immunoassays were performed to measure the production of P1P, MMP-1, MMP-2, and tissue inhibitor of metalloproteinase (TIMP)-1. To assess the production of MMP-2 its gelatinolytic activity was measured by zymography using gelatin-containing gels. The participation of transforming growth factor-,1 (TGF-,1) in the production and degradation of collagen was also investigated. Finally, the migratory activity of keloid fibroblasts was evaluated using a colony dispersion assay. Results, The production of type 1 collagen, MMP-1, MMP-2, and TIMP-1 by keloid fibroblasts was 3-fold, 6-fold, 2·4-fold, and 2-fold greater than that of normal dermal fibroblasts, respectively. Production of P1P was increased when TGF-,1 was added to cultures of keloid fibroblasts, while it was decreased when anti-TGF-,1 antibody was added to the cultures. In contrast, the production of MMP-1 was decreased by the addition of TGF-,1 to cultured keloid fibroblasts, while it was increased when anti-TGF-,1 antibody was added to the cultures. The production of MMP-2 increased after treatment with TGF-,1, but did not change significantly when anti-TGF-,1 antibody was added to the cultures. Production of TIMP-1 did not change significantly when either TGF-,1 or anti-TGF-,1 antibody was added to the cultures. Keloid fibroblasts showed a 2·5-fold increase of migratory activity compared with normal dermal fibroblasts, while the migratory activity of these fibroblasts was reduced to the control level by treatment with a broad-spectrum MMP inhibitor (GM 6001). Conclusions, Cultured keloid fibroblasts showed increased production of collagen and MMPs, and TGF-,1 played a role in this regulation of production. In addition, increased production of MMPs had a role in the high migratory activity of cultured keloid fibroblasts. [source] Increases in collagen type I synthesis in asthma: the role of eosinophils and transforming growth factor-b,CLINICAL & EXPERIMENTAL ALLERGY, Issue 6 2002A. Nomura Summary Background Collagen type I is one of the major deposits in thickening of the reticular basement membrane of asthma. Objective and Methods In this study, we assessed turnover of collagen type I in asthma by measuring procollagen type I C-terminal peptide (PICP) and collagen type I C-terminal telopeptide (ICTP) in induced sputum. Results PICP but not ICTP was found to be significantly higher in asthma subjects than in normal volunteers (P < 0.05). In asthma, PICP was inversely correlated with %FEV1.0 (r = ,0.539), and its levels significantly increased upon exacerbation (P < 0.05), indicating that collagen synthesis increases during asthma exacerbation. Additionally, PICP was found to significantly correlate with eosinophil counts in sputum (r = 0.539), indicating that eosinophils stimulate collagen turnover. Because eosinophils can produce TGF-,, a potent stimulator of collagen synthesis, we immunocytochemically examined TGF-,-positive cells in sputum. TGF-,-positive cells significantly correlated with eosinophil counts (r = 0.811) and PICP (r = 0.569), suggesting that TGF-, released from eosinophils is involved in collagen synthesis. Conclusions The results of the present study suggest that collagen synthesis is stimulated in asthmatic airways by eosinophils through TGF-,, while collagen degradation is not, and that PICP in sputum can act as a new marker for airway inflammation in asthma. [source] Erythropoietin administration does not influence the GH,IGF axis or makers of bone turnover in recreational athletesCLINICAL ENDOCRINOLOGY, Issue 3 2005A. E. Nelson Summary Objective, Measurement of biochemical markers of the IGF-system and of collagen turnover is a potential approach to detect GH abuse in sport. These markers are increased in patients on dialysis treated with recombinant human erythropoietin (r-HuEPO), mimicking the effects of GH. The aim was to determine whether r-HuEPO induces similar effects on the IGF-system and collagen turnover in healthy athletes. Subjects and measurements, Young male Caucasian recreational athletes were administered 50 U/kg r-HuEPO (n = 14) or placebo (n = 16) three times a week for 25 days, followed by a 4-week wash-out period. IGF-I, IGFBP-3, the acid labile subunit (ALS), N-terminal propeptide of type I collagen (PINP), C-terminal telopeptide of type I collagen (ICTP) and N-terminal propeptide of type III collagen (PIIINP) were measured in samples collected at baseline (two samples), after 10, 22 and 24 days of r-HuEPO treatment and at the end of the 4-week wash-out period. Results, Treatment with r-HuEPO resulted in approximately threefold elevation of serum EPO and marked elevation of markers of erythropoiesis. There was no significant treatment effect of r-HuEPO compared to baseline on IGF-I, IGFBP-3, ALS, PINP, ICTP or PIIINP. Conclusions, r-HuEPO administration did not change markers of the IGF-system and of collagen turnover in young healthy male athletes. Therefore, use of r-HuEPO in athletes should not affect the validity of a GH doping test using these GH-responsive markers. [source] Effects of short-term dexamethasone treatment on collagen synthesis and degradation markers in preterm infants with developing lung diseaseACTA PAEDIATRICA, Issue 5 2003T Saarela Aim: To assess the effects of dexamethasone treatment on collagen turnover in preterm infants. Methods: The serum concentrations of the amino-terminal propeptide of type I and III procollagens (PINP and PIIINP), which reflect rates of type I and III collagen synthesis, respectively, and the carboxyterminal telopeptide of type I procollagen (ICTP), which reflects the rate of type I collagen degradation, were monitored in 13 preterm infants receiving dexamethasone and 13 matched control infants without glucocorticoid treatment for a total period of 12 mo. Dexamethasone was started at a median age of 12 d and continued at tapering doses for a median total duration of 10 d. Blood samples were taken immediately after birth, at 7, 14 and 28 d of age and at 2, 3, 6, 9 and 12 mo. The same markers were also measured just before the initiation of dexamethasone and on days 1, 3, and 7 of treatment. Results: A striking decrease in all of the markers was already observed in every case on day 1 of dexamethasone, the suppression being greatest on day 3 and still considerable on day 7. The percentages from the pretreatment levels recorded on days 1, 3 and 7 were: for PINP 51, 26 and 45%; for PIIINP 63, 44% and 52%; and for ICTP 64, 41 and 51%. A rebound rise in PINP levels was seen in dexamethasone-treated infants, the levels exceeding those of the controls at 3 and 6 mo of age. A similar phenomenon was noted concerning PIIINP at 3 mo. The levels settled down at 9 and 12 mo. Conclusion: Dexamethasone causes an immediate, inevitable, deep suppression of type I and III collagen synthesis and also type I collagen degradation. This should be taken into consideration, e.g. when assessing for the indications for steroid treatment in sick preterm infants and its dosing and duration. [source] | ||||||||||