title: Time-Dependent Resolution of Collagen Deposition During Skin Repair in Rats: A Correlative Morphological and Biochemical Study.
abstract: Skin samples were used to compare microscopy methods used to quantify collagen with potential applicability to resolve time-dependent collagen deposition during skin wound healing in rats. Skin wounds by secondary intention were made in rats and tissue fragments were collected every 7 days for 21 days. Collagen content determined by biochemical analysis was compared with collagen measured by point counting (PC) on histological skin sections stained by Gomori's trichrome method (Trichrome/PC), Sirius red under polarized light (PL) microscopy (Sirius red/PL-PC), and computational color segmentation (CS) applied to sections stained with Sirius red (Sirius red/PL-CS). All microscopy methods investigated resolved the time-dependent dynamics of collagen deposition in scar tissue during skin wound healing in rats. Collagen content measured by Sirius red/PL-PC and Sirius red/PL-CS was significantly lower when compared with Trichrome/PC. The Trichrome/PC method provided overestimated values of collagen compared with biochemical analysis. In the early stages of wound healing, which shows high production of noncollagenous molecules, Sirius red/PL-CS and Sirius red/PL-PC methods were more suitable for quantification of collagen fibers. Trichrome staining did not allow clear separation between collagenous and noncollagenous elements in skin samples, introducing a marked bias in collagen quantification.
authors.affiliation: 1Department of Structural Biology,Federal University of Alfenas,Rua Gabriel Monteiro da Silva, 700,Campus Universitário,Centro,Alfenas,MG 37130-000,Brazil.
authors.forename: Rômulo D
authors.initials: RD
authors.lastname: Novaes
authors.affiliation: 2Department of General Biology,Federal University of Viçosa,Viçosa,MG 36570-000,Brazil.
authors.forename: Marli C
authors.initials: MC
authors.lastname: Cupertino
authors.affiliation: 2Department of General Biology,Federal University of Viçosa,Viçosa,MG 36570-000,Brazil.
authors.forename: Mariaurea M
authors.initials: MM
authors.lastname: Sarandy
authors.affiliation: 3Department of Animal Biology,Federal University of Viçosa,Viçosa,MG 36570-000,Brazil.
authors.forename: André
authors.initials: A
authors.lastname: Souza
authors.affiliation: 4Department of Anatomy,Federal University of Alfenas,Alfenas,MG 37130-000,Brazil.
authors.forename: Evelise A
authors.initials: EA
authors.lastname: Soares
authors.affiliation: 3Department of Animal Biology,Federal University of Viçosa,Viçosa,MG 36570-000,Brazil.
authors.forename: Reggiani V
authors.initials: RV
authors.lastname: Gonçalves
keywords: dermis; extracellular matrix; morphology; pathology; wound healing