| Summary: | 碩士 === 國立臺灣大學 === 醫學工程學研究所 === 96 === Soft tissue defects and tissue deficits resulted from congenital defects and acquired diseases are often occured in deep subcutaneous fat layer. A promising solution for these defects is tissue engineered adipose tissue. In addition to cells and scaffolds, signals are required to promote tissue regeneration. Drug controlled release systems are often used to protect and release these signals and microspheres fabricated by emulsion technique is a kind of drug carriers. In this study, we focused on the differentiation induced by microspheres which contained inducing factors in the collagen/ hyaluronic acid (HA) hydrogel scaffold.
In order to reconstruct soft tissue, we combine preadipocytes isolated from male Wistar rats cultured in collagen/ HA gels blended with microspheres containing insulin and dexamethasone. PDLLA microspheres containing insulin and dexamethasone were fabricated through emulsion technique and controlled release studies were conducted. These samples were analyzed using high performance liquid chromatography (HPLC) method and the cumulative release in a 70 days controlled-release experiment: the concentration of insulin and dexamethasone are 29.62 μg/ml and 2.4 μg/ml, respectively. According to the release studies and stability tests, we found that microspheres can controll release these two drugs. Then, preadipocytes were cultured with microspheres containing inducing factors, and adipogenesis were evaluated by Oil Red O staining. The adipogenesis induced by the microspheres containing insulin and dexamethasone was observed. We also found that incorporating adequate PDLLA microspheres into gel can promote cell proliferation through MTS assay. Moreover, the differentiation of preadipocytes in the gel was observed by nonlinear optical microscopy. We found that the formation of network structure in collagen gel caused by adding HA, and it may increase the mechanical properties and limit contraction of the gel. The formation of adipocytes in the gel was observed and this result can proof that adipogenesis can be induced by microspheres containing insulin and dexamethasone in the gel.
These results supported that insulin and dexamethasone can be controlled released from microspheres although the adipogenesis was still evaluated further. The combination of collagen/ HA gel with microspheres and preadipocytes is a promising tissue engineered adipose tissue.
|
|---|
