Análise fractal da remodelação tecidual e da distribuição de fibras colágenas no corpo lúteo bovino

Abstract

To assist in evaluating and quantifying tissue changes, fractal dimension (FD) becomes a useful method for assess the organization in an image from fractals that describe the amount of space and the self-similarity of the structure, once FD detects subtle morphological changes and performs functional quantitative measures. Here we hypothesized that fractal analysis will be different between functional and regressing bovine corpus luteum (CL) and it is correlated with differential expression of genes involved with extracellular matrix remodeling. The CL was classified into two developmental stages, the functional and regressing CL, according to progesterone levels and morphology. First, we found a lower fractal dimension in functional CL using a HE staining and a picrosirius red approach. Additionally, we found a great amount of total collagen in regressing CL. Regarding gene expression, we demonstrated an up regulation of COL1A1, COL1A2, MMP2 and MMP14, and a down regulation of TIMP1 and TIMP2 in regressing CL compare to functional one. Taken all results together, we concluded that differential FD observed during luteal regression showed that this analysis is an effective method to evaluate the tissue changes observed during luteal development in cattle, as well as, is related to differential quantity of genes involved with extracellular matrix remodeling.