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Poblete Jara, C.

Publications and source records attributed to Poblete Jara, C..

2 recordsLinked to original sources

A Diabetic Mice Model For Studying Skin Wound Healing

Advances in wound treatment depend on the availability of suitable animal models. All animal models try to reflect human wound healing problems. For acute wounds, it is easier to obtain adequate animal models, however, for chronic wounds such as those found in individuals with diabetic foot ulcer, approximations of the clinical picture become a challenge. Nowadays, the key points of wound healing processes are better understood, and therefore, therapeutic strategies can be developed to manipulate wound repair. Research efforts involves the development of therapies to aid in the treatment of impaired wound healing and, to improving normal wound healing to drive a process close to regenerative. To achieve a better animal model that is more appropriate for studying wound healing, six-week- old male C57BL/6 mice were separated into groups fed a Chow and High-Fat Diet for 0.5, 3, and 6 months, when part of the animals were induced to diabetes by streptozotocin. Then, mice were submitted to metabolic, molecular, and morphological analyses. We show that this model results in a severe metabolic phenotype with insulin resistance, reduced insulin expression, and glucose intolerance associated with obesity and, more importantly, skin changes. Furthermore, the skin phenotype, both structurally and transcriptionally, overlapped with conditions found in elderly patients with DM that reproduce the phenotype of most patients who develop diabetic foot ulcers.

physiology↗

Demonstration of re-epithelialization in a bioprinted human skin equivalent wound model

ObjectiveThe development of an in vitro platform for modeling human skin injury and the re-epithelization process. ApproachA fibrin provisional matrix (FPM) was installed into a wound facsimile of a bioprinted human skin equivalent (HSE). A mixture of plasma-derived fibrinogen-containing factor XIII, fibronectin, thrombin, and macrophages (an FPM "bioink") was extruded into the wound site. The surrounding in vitro tissue culture became a source of keratinocytes to achieve wound closure by a re-epithelialization process signaled by the FPM. ResultsAn in vitro analog of wound closure and re-epithelialization by keratinocytes occurred over the FPM after a normal migration initiation at 3 days. InnovationA physiologic mixture of macrophage/fibrinogen/fibronectin that supports macrophage differentiation was applied to a mechanically wounded, bioprinted dermal tissue. We developed a transitional culture medium to mimic the changing microenvironment during the initial phases of wound healing. As a reference, we temporally compared our in vitro model with a murine skin wound healing. ConclusionThis co-culture model was shown to temporally synchronize a re-epithelization process for initiation of keratinocyte migration from a surrounding tissue and the migration process over the top of an FPM. A future study of the analogous subepithelial healing pathway is envisioned using the same in vitro bioprinted tissue study platform for co-culture of keratinocytes, melanocytes, fibroblasts, endothelial cells, and macrophages using more specialized FPMs.

bioengineering↗