Thermal analysis characterization of aortic tissues for cardiac valve bioprostheses

Abstract

Two multistep extractions were achieved on porcine aortic tissues to obtain acellular matrices used for cardiac bioprostheses. The evaluation of structural modifications and the possible damage of extracellular matrix fibrous proteins were investigated by means of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Protein-water interactions and degradation temperatures were determined by TGA. DSC was used to characterize protein thermal transitions (glass transition and denaturation), which provided information on the dynamic structure of the aortic tissue components. Sodium dodecyl sulfate (SDS) extraction had a destructuring effect, while Triton and cholate treatments did not affect the structural integrity of either elastin and collagen. A DSC comparison showed that SDS destabilizes the collagen triple helical domain and swells the elastin network.

The influence of heart valve leaflet matrix characteristics on the interaction between human mesenchymal stem cells and decellularized scaffolds

“…Most collagen fibrils and elastic fibers exhibit well-preserved ultrastructural features (Figs. 7 and 8) -a situation consistent with our previous results [4][5][6] -therefore the gross distribution of collagen and elastin is left unchanged with respect to the native ECM [32]. These ultrastructural patterns are also confirmed for the human cryopreserved specimens (Fig.…”

“…Basically, this twostep procedure includes preparing xeno-or homogeneic valve matrices [4] with mechanical and functional properties suitable for cell engraftment. We recently set up a technique for decellularizing porcine heart valve leaflets using a non-ionic detergent, Triton X100, which enables scaffolds with an optimally preserved collagenouselastic network to be achieved [5,6]. It is particularly important to select cell type(s) suitable for an appropriate valve cell colonization in vitro in static conditions or in a bioreactor.…”

“…This drawback can be overcome by using decellularized scaffolds, which act as ideal supports for cell attachment and differentiation because the native leaflet fiber integrity and alignment are preserved [5,6,19], as demonstrated by recolonizing valve scaffolds with VICs [4]. In this study, we first investigated cell adhesion, spreading and potential for differentiation of hBM-MSCs seeded statically onto the two anisotropic microstructures of ventricularis and fibrosa of porcine valve leaflets.…”

Non Thermal Plasma Sources of Production of Active Species for Biomedical Uses: Analyses, Optimization and Prospect

“…A large endothermic phenomenon is observed for the different collagen samples between 50°C and 150°C. This can be attributed to the evaporation and vaporization of residual bound water in collagen (Samouillan et al 1999). A second endothermic event is observed above 200°C for all the samples with a specific shape for each sample.…”

Stability of peritoneal tissue evaluated by the means of DSC in obese patients undergoing laparoscopic cholecystectomy

“…The DSC method has proven to be a valuable tool in assessing the role of collagen in structural alterations of several cardiovascular and musculoskeletal diseases [8][9][10][11]. Our previous study showed that DSC was the appropriate method for investigation of subtle changes in physicochemical conditions of peritoneum using tissues obtained during surgical procedures [12].…”