Changes In Collagen Type Research Articles

Altered collagen synthesis in fascia transversalis of patients with inguinal hernia

The aim of this study was to substantiate the hypothesis as to whether an altered metabolism of type I and type III collagen should be included as pathophysiological considerations of inguinal hernia development or not. Therefore, fascia transversalis derived from patients with indirect hernias (n=9), direct hernias (n=7) and from controls (n=7) were investigated both by immunohistochemistry and protein analysis (Western Blot). Both immunohistochemical analysis and Western Blot analysis showed that the ratio of the relative amounts of type I to type III collagen was significantly decreased in the fascia transversalis of patients with indirect and direct inguinal hernias compared with controls (p<0.001). The relative reduction of the collagen I/III ratio may be explained by a concomitant increase in collagen type III synthesis in both hernia-families. In contrast to the control group there was no significant difference between patients with direct and indirect hernia. It is concluded that the change in collagen type I / III ratio, with the resulting altered physical properties, might essentially predispose individuals to the development of inguinal hernia. Thus, an altered collagen metabolism would provide an additional theoretical basis for the use of alloplastic materials, such as surgical meshes, and an explanation for the disappointing high recurrence rates after appropriate primary hernia repair, particularly if mesh-free techniques have been used.

Left and right ventricular collagen type I/III ratios and remodeling post-myocardial infarction

Background: Types I and III collagen have different physical properties, and an increase of type I/III ratio can have a deleterious impact on myocardial compliance and left and right ventricular diastolic function. Post-myocardial infarction, these changes in collagen types may be relevant to the remodeling process and the development of heart failure. Methods and Results: In the rat coronary ligation heart failure model, we studied the time course of changes in types I and III and total collagen levels over 10 weeks postinfarction. Collagen types were separately quantified in the left (LV) and right ventricles (RV) by computerized morphometry and standard immunohistochemistry techniques, and also by hydroxyproline analysis, and these were correlated with hemodynamic changes. Compared with sham-operated rats, total collagen level increased 2.5- to 2.9-fold and 1.7- to 2.9-fold in the noninfarcted areas (NIAs) of the LV and RV, respectively, over the 10-week period and showed a good relation with changes in hydroxyproline content ( r 2 = 0.62; P < .0001). In the NIAs of both the LV and RV, type III collagen level showed a transient twofold increase at 2 weeks, which declined to normal at 4 weeks. Type I collagen level increased twofold at 4 weeks in the NIA of the LV and remained elevated at 10 weeks. In the RV, type I collagen level increased 2.7-fold to a peak at 4 weeks and declined gradually to 1.7 times baseline at 10 weeks. The patterns of change in type I collagen level in the RV correlated with the changes in LV end-diastolic pressure ( r = 0.73; P < .0001) and RV weight to body weight ratio ( r = 0.73; P < .0001). Conclusion: There is a relative greater increase of type I collagen level in the NIA and RV postinfarction, and this may lead to left and right ventricular dysfunction. Separate mechanisms might be involved in the induction of the different types of collagen deposition, with type I collagen levels apparently closely correlating with hemodynamic stress.

Collagen Types I and III Localization by In Situ Hybridization and Immunohistochemistry in the Partially Obstructed Young Rabbit Bladder

Purpose The objective of the study was to investigate the alteration of collagen expression patterns at the transcription and translation levels during partial outlet obstruction and to compare changes in collagen types I and III gene expression, and protein deposition during early and subacute phases of obstruction. Materials and Methods Following 1, 2, 7, 14 and 21 days of partial bladder obstruction in 2-week-old rabbits bladder tissues were evaluated for collagen types I and III messenger ribonucleic acid localization by in situ hybridization and for protein localization by immunohistochemical study. Results There is up regulation of collagen types I and III gene expression after obstruction. Up regulation of collagen gene expression immediately after obstruction is within the lamina propria and the message moves into the muscular layer as obstruction progresses. Protein deposition for both collagen types is analogous to that of gene expression. Conclusions Up regulation of collagen types I and III gene expression, and increased protein deposition after partial obstruction demonstrate that the alteration in collagen synthesis is at least partially transcription regulated. This alteration starts from superficial layers of the bladder wall and becomes deeper as the pathological process progresses.

Collagen types I and III localization by in situ hybridization and immunohistochemistry in the partially obstructed young rabbit bladder.

The objective of the study was to investigate the alteration of collagen expression patterns at the transcription and translation levels during partial outlet obstruction and to compare changes in collagen types I and III gene expression, and protein deposition during early and subacute phases of obstruction. Following 1, 2, 7, 14 and 21 days of partial bladder obstruction in 2-week-old rabbits bladder tissues were evaluated for collagen types I and III messenger ribonucleic acid localization by in situ hybridization and for protein localization by immunohistochemical study. There is up regulation of collagen types I and III gene expression after obstruction. Up regulation of collagen gene expression immediately after obstruction is within the lamina propria and the message moves into the muscular layer as obstruction progresses. Protein deposition for both collagen types is analogous to that of gene expression. Up regulation of collagen types I and III gene expression, and increased protein deposition after partial obstruction demonstrate that the alteration in collagen synthesis is at least partially transcription regulated. This alteration starts from superficial layers of the bladder wall and becomes deeper as the pathological process progresses.

TGF-βPromotes the Growth of Bovine Chondrocytes in Monolayer Culture and the Formation of Cartilage Tissue on Three-Dimensional Scaffolds

We have investigated the ability of transforming growth factor beta (TGF-beta) to promote the growth and differentiation of chondrocytes in monolayer and on three-dimensional scaffolds. Treatment of chondrocytes with TGF-beta and ascorbate individually stimulated the proliferation of bovine articular chondrocytes about 2-fold when cells were grown in monolayer culture: the combination of TGF-beta and ascorbate resulted in a 3-fold increase in cell number over a 72-h period. Peak stimulation with TGF-beta occurred at about 1.0 ng/ml: bFGF was slightly inhibitory in these assays. TGF-beta led to an increase in glycosaminoglycan synthesis as detected by Western blotting using anti-chondroitin sulfate antibodies. No significant change in collagen type II mRNA or protein was observed. When cells were grown on grown on three-dimensional scaffolds composed of polyglyocolic acid, TGF-beta treatment led to an increase in the size of the cartilage-like constructs produced. This was accompanied by increases in collagen and glycosaminoglycan deposition; immunohistochemical staining showed that the predominant collagen was type II. These results indicate that TGF-beta is capable of increasing the proliferation rate of chondrocytes in monolayer as well as increasing cartilage production on three-dimensional scaffolds and may find utility in the in vitro engineering of cartilage tissue.

Different effects of an angiotensin converting enzyme inhibitor and a calcium antagonist on protein metabolism in rats with right ventricular hypertrophy

We examined the effects of a calcium antagonist and an angiotensin converting enzyme (ACE) inhibitor on contractile and non-contractile protein metabolism and cardiac function in a monocrotaline-induced right ventricular hypertrophy model, in order to define the effects of these drugs on cardiac hypertrophy. One week after monocrotaline injection, male Sprague-Dawley rats were given either a calcium antagonist (nilvadipine; 3 mg/kg per day) or an ACE inhibitor (delapril-HCl; 30 mg/kg per day) for 2 weeks. Right ventricular pressure, the right ventricle: (left ventricle + interventricular septum) ratio, myosin isoenzymes, collagen concentration, collagen types and contractility of right ventricular free wall were examined. In untreated rats significant monocrotaline-induced right ventricular hypertrophy with an increase in the proportion of collagen types III and V was observed. There were no significant changes in collagen concentration. Both drugs reduced right ventricular pressure to the same degree and decreased right ventricular hypertrophy. However, the inhibitory effect of delapril on right ventricular hypertrophy was stronger than that of nilvadipine. Nilvadipine reduced the collagen concentration and reversed changes in collagen types, whereas delapril did not have any significant effect on collagen concentration or collagen types. Cardiac contractility was improved by delapril, but not by nilvadipine. The results show that a calcium antagonist disproportionately inhibited contractile and non-contractile protein metabolism, whereas an ACE inhibitor proportionally inhibited them and improved cardiac function in a model of right ventricular hypertrophy. The improvement in cardiac function may be due partly to the proportional inhibition of contractile and non-contractile proteins elicited by an ACE inhibitor.

Analysis of collagen type III by uninterrupted sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting: changes in collagen type III polymorphism in aging rats.

A new method of type III collagen analysis by uninterrupted sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) combined with immunoblotting was developed. The electrophoresis was carried out with gels containing 4 M urea. A negatively charged reducing agent, thioglycolic acid, was added to the running buffer of the cathodic reservoir between 15 and 20 min after Bromphenol Blue (BPB) migrated to the top of the separating gel, to reduce interchain disulfide binding of the collagen. The polymorphic type III collagens, i.e., an alpha-chain derived from a trimer [alpha 1(III)]3 with interchain disulfide bonds but without covalent cross-links, alpha 1(III), a beta-chain with covalent cross-links, beta(III), or an alpha-chain released from a trimer without reduction of the disulfide bonds, alpha*1(III), were identified by immunostaining and quantified by densitometry. Using this method, changes in collagen type III polymorphism with aging were examined in the aorta, brachial artery, and skin of rats. The total quantity of collagen type III decreased with aging in all tissues. beta(III) was the major component in the aorta and brachial artery, but alpha 1(III) was the major component in the skin. With increasing age from 3 to 60 weeks, the ratio of beta(III) to alpha 1(III), which is correlated with the extent of covalent cross-linking, showed a steep increase in the aorta but only a slight increase in the skin and it remained almost constant in the brachial artery.(ABSTRACT TRUNCATED AT 250 WORDS)

Premature Rupture of Fetal Membranes Changes in Collagen Type

Collagen from the chorioamnion units from premature and term pregnancies was solubilized by limited pepsin digestion and subjected to SDS-PAG electrophoresis. Collagen types were quantitated by densitometry. It was found that collagen type III decreases and collagen type V tends to increase as gestational age advances. Investigating the relative abundance of collagen types at various membrane sites from term pregnancies revealed that type V decreases in the amnion as the rupture site is approached. It is concluded that since type V collagen is more resistant to collagenases, its decrease may predispose that particular site to rupture.

Premature Rupture of Fetal Membranes Changes in Collagen Type

Premature Rupture of Fetal Membranes Changes in Collagen Type

Changes in collagen types I and III with age

Changes in collagen types I and III with age

Biosynthesis and Degradation of Collagen in X-Irradiated Mouse Lung

Fibrosis, characterized by accumulation of collagen, is a delayed result of radiation injury in many tissues, including lung. To investigate its development, synthesis and degradation of collagen were measured in lungs of mice after X irradiation of the whole thorax. The ratio of type I (coarse fibered) to type III (meshwork) collagen was also determined. Synthesis of procollagen, measured as the activities of prolyl-4-hydroxylase and protein disulfide isomerase in lung tissue, was increased at 2 months after X-ray doses of 5, 7.5, and 9 Gy. Maximal increases were observed 6 to 7 months after doses of 9 Gy and persisted up to 15 months after exposure. Increases after 5 and 7.5 Gy were more gradual, but by 1 year after irradiation they had reached levels similar to those after 9 Gy. X irradiation had no effect on the degradation of collagen as assessed by collagenase activity in lung. The ratio of type I to type III collagen, analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of collagen-derived cyanogen bromide peptides, was the same in irradiated lungs as in age-matched controls. Therefore, increased synthesis of procollagen, rather than decreased degradation of collagen or changes in collagen type, is an important factor in the accumulation of collagen in irradiated lung.

INCREASED TYPE V COLLAGEN IN THE STRICTURES OF CROHN'S DISEASE

Histologic studies of strictured intestine in Crohn's disease have revealed an accumulation of collagen and a proliferation of smooth smooth muscle cells. In order to determine if these changes were associated with changes in collagen types, collagen was isolated (acetic acid extraction, limited pepsinisation and salt precipatation) from control intestine, inflamed intestine, and strictured intestine resected from patients with Crohn's disease and collagen types separated by slab gel electropheresis, and quantitated by densitometry. The major collagen type in control intestine was Type I followed by Types III and V. In strictured intestine the relative amount of Type V collagen was significantly increased. Quantitation of hydroxyproline content of the specimens by acid hydrolysis and HPLC demonstrated a significant (p<0.05) increase in collagen per unit area of mucosa in strictured (2308±269 nM) vs. control (1706±122 nM) intestine. Intestinal strictures in Crohn's disease contain increased Type V collagen. These data, in conjunction with the histologic data, suggest a significant role for smooth muscle cells in intestinal fibrosis. Supported by NIH grant AM34151 and the NFIC.

Connective tissue metabolism in muscular dystrophy. Early amino acid changes in collagen types isolated from the gastrocnemius muscle of developing dystrophic chicken embryos

1. 1. The amino acid composition of all collagen types present in the gastrocnemius muscle of dystrophic chick embryos showed an altered profile at both day 14 and day 20 in ovo when compared with the controls. 2. 2. The changes observed at both day 14 and day 20 in ovo suggests that there is a removal of polar side-chains in dystrophic collagen and substitution with non-polar amino acids. 3. 3. The amino acid composition data between day 14 and day 20 indicated: (a) a decrease in hydroxylation (hydroxyproline and hydroxylysine) with a concurrent increase in proline and lysine and a decrease in the levels of arginine; (b) the levels of glycine and alanine did not change with age; and (c) the ratios of glycine to hydroxyproline and proline to hydroxyproline changed significantly in all dystrophic collagen types between day 14 and day 20. 4. 4. Contrast analysis results clearly showed that the changes in amino acid composition observed in each dystrophic type of collagen between day 14 and day 20 were not due to the effect of aging but to some other factor(s). 5. 5. This study provides more evidence that a problem lies in the biosynthesis of collagen present in developing muscles of dystrophic chick embryos, particularly with respect to the transcription or translation of procollagen genes and/or a failure in the processing and differentiation of collagen types.

Changes in collagen types during the healing of rabbit tooth extraction wounds.

Three alpha chains of type V collagen--alpha 1 (V), alpha 2 (V), and alpha 3 (V)--were initially demonstrated together with the expected collagen types I and III in the pepsin-soluble fraction of both normal mandibular bone and tooth extraction wound tissues of rabbits, as analyzed by sodium dodecyl sulfate-gel electrophoresis. The total collagen content of each extraction wound, as determined by the hydroxyproline assay, was observed to increase continuously from day 5 through day 17 and then leveled off or decreased. The ratio of type V to type I collagen was significantly higher in the initial stage of wound healing and decreased sharply down to the level of mandibular bone by day 5. The ratio of type III to type I collagen in the pepsin-soluble fraction increased and reached a maximum on day 5, whereas it was maximal on day 7 in the cyanogen bromide-soluble fraction, and thereafter decreased gradually in both fractions. The ratio for the pepsin-soluble fraction was, however, significantly higher than that for the cyanogen bromide-soluble fraction in the early stage of wound healing.

Proteochondroitin sulfate synthesized in cartilages induced in vivo and in vitro by bone matrix gelatin

Implanted allogeneic demineralized bone matrix gelatin induced sequential development of cartilage and bone in the recipient rat muscle tissue. Proteoglycans of the implants labeled in vivo with [ 35S]sulfate at different stages of development were analyzed by sucrose density gradient centrifugation. The major proteoglycan synthesized in day-5 implant, just prior to onset of chondrogenesis, was a dermatan sulfate-containing proteoglycan with relatively slow sedimentation rate. Additionally, a small amount of a faster sedimenting component could be detected. The faster sedimenting proteoglycan, in which chondroitin 4-sulfate accounted for 85% of total radioactivity, became predominant in day-10 sample when cartilage formation was maximal. By day 30, when cartilage had been replaced by newly formed bone, the synthesis of this faster sedimenting component had ceased. A similar, if not identical, proteoglycan was found to be a major one synthesized by the in vitro-induced cartilage. This proteoglycan was smaller in overall size and shorter in length of its chondroitin sulfate chains than a major proteoglycan component obtained from neonatal rat epiphyseal cartilage. Concurrent with these changes in proteoglycan type, there appeared to be a change in collagen type, since type II collagen, in addition to type I collagen, was synthesized in day-10 implant. These results indicate that the proteoglycan can be used as a molecular marker for chondrogenesis by bone matrix gelatin.

Changes in type of collagen during the development of human post-burn hypertrophic scars

Neutral-salt soluble collagen was relatively abundant in young post-burn hypertrophie scars. The content of insoluble collagen was fairly low in granulation tissues, whereas it gradually increased over 2 years and reached a significantly higher value than that in normal skins. Interrupted gel electrophoresis was carried out to estimate the relative proportions of type III and type I collagens in the pepsin digests of human normal skins and post-bum scars. Granulation tissues showed an abnormally higher ratio of type III to type I (0.37–0.72) than the mean value of normal skins (0.17 ± 0.04 (S.D.)). The ratio gradually decreased to the normal range after 2 years or so.

Changes in type of collagen synthesized by chick fibroblasts in vitro in the presence of 5-bromodeoxyuridine

Chick embryo fibroblasts cease to synthesize their normal collagen product when grown in the presence of the thymidine analogue, 5-bromodeoxyuridine (BrdU). The drug causes an alteration of synthesis from the normal Type I collagen ( α1(T) 2 α2) to a mixture of Type I and Type I trimer ( α1(I) 3). While the significance of the synthesis of Type I trimer is unclear, it has been noted that chondrocytes synthesize this collagen type following in vitro senescence and in the presence of BrdU. Since BrdU may cause a switching in the temporal pattern of collagen biosynthesis in chondrocytes and in fibroblasts it is proposed that BrdU may alter the normal regulatory controls acquired by the cells during the course of their differentiation. The synthesis of Type I trimer might provide a marker for such a break-down in a wide variety of cell types.

Changes in type of collagen synthesized as clones of chick chondrocytes grow and eventually lose division capacity.

Clones of embryonic chick chondrocytes have been isolated and collagen biosynthesis has been followed as the clones grow and eventually lose division capacity. Analysis of collagen type at each successive subculture until the time of cellular senescence has shown that a change in synthesis occurs from the cartilage-specific Type II collagen (chain composition [alpha1(II)]3) to a mixture of Type I collagen (chain composition [alpha1(I)2alpha2) and the Type I trimer (chain composition[alpha1(I)]3). The results demonstrate unequivocally that the expression of the chick chondrocyte phenotype is unstable in vitro, and that previous experiments with mass cultures of chondrocytes cannot be accounted for by overgrowth of fibroblasts. Since similar morphological changes and a similar "switching" in collagen biosynthesis have been observed after growth of chondrocytes for a few days in 5-bromo-2'-deoxyuridine, it is proposed that growth in this analog accelerates those changes that eventually lead to cellular senescence.