Combination of aloe vera improves the biological performance of chitosan membranes for skin tissue repair

Publicado em "Journal of Tissue Engineering and Regenerative Medicine", vol. 7, suppl. 1 (2013)

In the last years, aloe vera (AV), a tropical plant belonging to theliliaceaefamily, has gained popularity for medical, cosmetic and nutritional purposes. Commercially, AV appears in food supplements, as additive to drinks, coating fruits, moisturizer, and healing agent in cosmetic products, among others uses. The interest in AV comes from its chemical diversity and biological properties, which includes analgesic, antiinflammatory, wound healing, antibacterial, immune modulation and anti-tumor activities. Therefore, the use of the therapeutic properties of AV gel could be very useful in the creation of materials for regenerative medicine. In the present work, the biomedical potential of systems composed by AV gel and chitosan (Cht), a natural polysaccharide, was assessed by processing them into membranes by solvent casting. Additionally, the blended system was crosslinked with genipin, a natural crosslinker agent. The crosslinking will bring the possibility to control the leaching out of AV gel portion from the blended membranes. The developed blended membranes were characterized by rough surfaces and controllable degradation behavior. Besides, the non- and crosslinked blended membranes have an increased stiffness and viscoelastic behavior as compared to chitosan membranes. Thus, these membranes will facilitate the penetration of the AV gel onto the skin, and the membrane may act at different stages of the healing process, while protecting the injury from infection. Additionally, chitosan will increase the stability of the polysaccharides and/or compounds present in the AV composition, which can in turn keep their natural biological activity. To examine cell behavior in the developed membranes, human dermalfibroblasts (hDfs) were seeded in the membranes. The results haven shown that the blended membranes were more favorable for hDfs adhesion and proliferation in comparison with chitosan membranes. Furthermore, the calcein-AM results are in agreement with the findings obtained from the alamar blue assay (cellular viability) and DNA quantification (cell proliferation), suggesting that they are viable independently of the cell number present on the membrane surface. All findings indicated that the produced blended membranes present adequate properties for skin applications, namely as wound dressing materials.