hydroxylysine and Cicatrix

This paper reviews some of the biochemical modifications involved in fibrous tissue formation and discusses possible ways of controlling fibrosis in clinical conditions. The lathyritic agents, beta-aminoproprionitrile (BAPN) and penicillamine, appear in certain situations to be able to control fibrosis by blocking the biosynthesis of collagen. There are no compounds that are yet known which are capable of reversing pre-existing fibrosis and future research may perhaps be more profitably directed towards the stimulation of collagen catabolism rather than the inhibition of its synthesis.

Topics: Aminopropionitrile; Animals; Cicatrix; Collagen; Cortisone; Humans; Hydroxylysine; Hydroxyproline; Liver Cirrhosis; Penicillamine; Procollagen; Rats; Wound Healing

Laser therapy is today considered the treatment of choice for vascular skin lesions, which commonly are located on the face and, therefore, frequently are exposed to sunlight. The purpose of this study was to examine whether preoperative and postoperative ultraviolet irradiation influences the development of laser-induced side effects. We laser-treated hairless mice with a copper vapor laser; three different intensities were used at a constant pulse duration. Simulated solar ultraviolet radiation was administered either before the laser treatment (3 consecutive days, daily doses of 2.48 J/cm2) or after the laser treatment (four times weekly in 4 weeks, daily doses of 1.66 J/cm2). Laser-induced wounds, scars, and hyperpigmentation were evaluated by macroscopic, histologic, and biochemical examinations. Preoperative ultraviolet exposure enlarged the laser-induced wounds and the areas with texture change at some of the laser intensities used. However, the most pronounced effect was seen for postoperative ultraviolet-irradiated mice. These mice developed, at some of the laser intensities, a higher incidence of bulging infiltration as well as higher degrees of fibrosis and hyperpigmentation, thus developing a poor cosmetic appearance. Furthermore, ultraviolet irradiation after laser treatment resulted in slowly healing wounds of reduced size, indicating deep, constricted skin damage. We conclude that ultraviolet exposure before and after copper vapor laser treatment increases the risk of inducing side effects from dermatological laser treatment.

Topics: Animals; Cicatrix; Contracture; Copper; Dermatologic Surgical Procedures; Esthetics; Facial Dermatoses; Female; Fibrosis; Hydroxylysine; Hydroxyproline; Hyperpigmentation; Incidence; Laser Coagulation; Mice; Mice, Hairless; Mice, Inbred C3H; Mice, Inbred Strains; Proline; Radiation Dosage; Risk Factors; Skin; Skin Diseases; Skin Diseases, Vascular; Skin Pigmentation; Sunlight; Ultraviolet Rays; Wound Healing

Scarring is a well-known side effect to cutaneous laser treatment. Therefore we investigated if wounds and scarring could be decreased by pharmacological interference in the acute inflammatory reaction following laser therapy. A copper vapor laser operating at 578 nm was used at three different intensities and doses. The antiinflammatory drugs methylprednisolone (1 mg/kg/24 h) and indomethacin (2 mg/kg/24 h) were administered through the drinking water. The laser induced wounds were evaluated daily and histologic and biochemical analyses were used to estimate scarring. The administration of antiinflammatory drugs resulted at some laser intensities in increased scores of maximum wound area, healing time, cumulated wound area, fibrosis, hydroxyproline, and hydroxylysine, being mostly pronounced for indomethacin at 0.8 W/spot. The maximum wound area and the wound healing time could be used as a predictor of scarring. A dose response was shown between the laser intensities and the mentioned parameters. We recommend carefulness in the laser treatment of patients receiving indomethacin and disrecommend use of the drug in the prophylaxis against laser induced scarring.

Topics: Administration, Oral; Animals; Burns; Cicatrix; Dose-Response Relationship, Radiation; Female; Fibrosis; Hydroxylysine; Hydroxyproline; Indomethacin; Laser Therapy; Methylprednisolone; Mice; Mice, Inbred C3H; Mice, Nude; Proline; Skin; Wound Healing

Scarring is a well-known side-effect of cutaneous laser treatment and exposure to solar ultraviolet radiation is suspected to increase scar formation. We investigated how wounds and scarring were modified by interfering in the laser-induced inflammation using ultraviolet radiation and para-aminobenzoic acid. A copper vapour laser operating at 578 nm was used at three different intensities and doses. The ultraviolet radiation was administered three times weekly prior to and four times weekly after the laser treatment. The daily dose was 21.5 kJ/m2 equivalent to 3.5 Basic-MED. The laser-induced wounds were evaluated daily and histological and biochemical analyses were used to estimate scarring. Ultraviolet irradiation resulted at some of the used laser intensities in decreased scores of maximum wound area, wound healing time, cumulated wound area, and a decreased skin content of hydroxyproline, whereas the degree of the chronic fibrosis tended to increase. Application of para-aminobenzoic acid before the solar ultraviolet irradiation did not change the acute wound scores but reduced, although not significantly, the degree of fibrosis.

Topics: 4-Aminobenzoic Acid; Animals; Cicatrix; Female; Fibrosis; Hydroxylysine; Hydroxyproline; Laser Therapy; Lasers; Mice; Mice, Hairless; Skin; Ultraviolet Rays; Wound Healing

Some biochemical characteristics of collagen extracted from granulation tissue were studied and compared with those of normal skin and scar. By using electrophoretic techniques the type III collagen content was confirmed to be significantly greater in granulation tissue and lower in scar with respect to normal skin. The chromatographic determination of hydroxylysine (Hyl) glycosides in collagen extracted from granulation tissue showed a significant increase in both the degree of Hyl glycosylation and in the di-/monoglycoside ratio, while both parameters turned out to be lower in scar. These data suggest that the degree of Hyl glycosylation and the di-/monoglycoside ratio could represent an index of the degree of collagen fiber maturation.

Topics: Cicatrix; Collagen; Glycosylation; Granuloma; Humans; Hydroxylysine; Skin

A modification of the existing methods for measuring hydroxylysine, galactosylhydroxylysine, and glucosylgalactosylhydroxylysine is described. The method is based on analysis with an automated amino acid analyzer using a conventional separation system for basic amino acids. The prior removal of acidic and neutral amino acids was necessary. This was achieved by passing an alkaline hydrolysate of collagen through a column of Amberlite CG-120, Type II (H+) and washing the column with 8% aqueous pyridine. A basic fraction containing the hydroxylysine compounds was then recovered from the column by elution with 3 M NH4OH. Model experiments showed that hydroxylysine and its glycosides could be analyzed with an hour and that recoveries exceeded 90%. This method was applied to human tissues to investigate whether the dermal scar is different in collagen composition from normal skin. With the limited number of samples analyzed, the data suggested that long-standing scar tissues reverted to a composition similar to that of normal skin. The composition of hydroxylysine-linked carbohydrate units is also discussed on the basis of the age-related change.

Topics: Adolescent; Adult; Aging; Chemical Phenomena; Chemistry; Child; Cicatrix; Collagen; Galactosides; Glucosides; Humans; Hydrolysis; Hydroxylysine; Methods; Middle Aged; Skin; Time Factors

Collagen similar to the collagen found in embryonic skin (same intermolecular cross-links and same structure of the polypeptide chains) is synthesized in young human scars. Later on, in normal scars, this collagen is replaced by the collagen of adult skin progressively. In contrast, in hypertrophic scars, a high proportion of collagen of "embryonic" type is present permanently. In granulation tissues of chronic inflammation, experimentally developed in rats, similar "embryonic" collagen has been found ; these granuloma are proposed as a model in laboratory animals of human hypertrophic scars.

Topics: Animals; Cicatrix; Collagen; Dipeptides; Humans; Hydroxylysine; Macromolecular Substances; Norleucine; Rats; Skin; Time Factors; Water

Insoluble guinea-pig skin collagen and insoluble dermal scar collagen were cleaved with CNBr and the peptides derived from the alpha1-chain were separated by ion-exchange and molecular-sieve chromatography. Comparison of the peptides from scar collagen with those from skin collagen showed that the former contained more hydroxylysine. Separation of the CNBr peptides showed that this increase in hydroxylysine was found not only in the non-helical regions, but was also seen down the helical portion of the molecule. Separation of the peptides revealed the presence of more peptides in digests of skin collagen than those of scar, and these have been attributed to the presence of Type III collagen in skin, but no evidence was found for the presence of this Type III collagen in dermal scar tissue.

Topics: Amino Acids; Animals; Chromatography; Cicatrix; Collagen; Cyanogen Bromide; Guinea Pigs; Hydroxylysine; Peptide Fragments; Protein Conformation; Skin

The collagen produced in response to an injury of human skin is initially stabilized by a cross-link derived from hydroxyallysine, and characteristic of embryonic skin. In normal healing there is a change over with time to the cross-link derived from allysine, which is typical of young skin collagen. In contrast, hypertrophic scars fail to follow the time-related changes of normal skin, but retain the characteristics of embryonic collagen, indicating a continued rapid turnover of the collagen. This is further supported by the high proportion of the embryonic Type III collagen present in hypertrophic scars.

Topics: Adolescent; Adult; Amino Acids; Child; Cicatrix; Collagen; Elastin; Humans; Hydroxylysine; Hypertrophy; Macromolecular Substances; Middle Aged; Protein Binding; Skin; Solubility; Time Factors; Water

Topics: Animals; Bacteria; Carbon Radioisotopes; Chromatography, Ion Exchange; Chromatography, Paper; Cicatrix; Collagen; Cornea; Electrophoresis, Paper; Galactose; Glucose; Glycosides; Hydrolysis; Hydroxylysine; Lysine; Microbial Collagenase; Rabbits; Time Factors; Tryptophan; Ultrafiltration

Topics: Aminocaproates; Animals; Borohydrides; Chromatography; Cicatrix; Collagen; Guinea Pigs; Hydrolysis; Hydroxylysine; Oxidation-Reduction; Skin; Tritium