RESUMO
Development and selection of an ideal scaffold is of importance for tissue engineering. Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx) is a biocompatible bioresorbable copolymer that belongs to the polyhydroxyalkanoate family. Because of its good biocompatibility, PHBHHx has been widely used as a cell scaffold for tissue engineering. This review focuses on the utilization of PHBHHx-based scaffolds in tissue engineering. Advances in the preparation, modification, and application of PHBHHx scaffolds are discussed.
Assuntos
Humanos , /química , Materiais Biocompatíveis/química , Caproatos/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , /uso terapêutico , Materiais Biocompatíveis/uso terapêutico , Osso e Ossos/fisiologia , Caproatos/uso terapêutico , Cartilagem/fisiologia , Liofilização , Músculo Liso/fisiologia , Regeneração , Propriedades de SuperfícieRESUMO
SRY-related high-mobility-group box 9 (Sox9) gene is a cartilage-specific transcription factor that plays essential roles in chondrocyte differentiation and cartilage formation. The aim of this study was to investigate the feasibility of genetic delivery of Sox9 to enhance chondrogenic differentiation of human umbilical cord blood-derived mesenchymal stem cells (hUC-MSCs). After they were isolated from human umbilical cord blood within 24 h after delivery of neonates, hUC-MSCs were untreated or transfected with a human Sox9-expressing plasmid or an empty vector. The cells were assessed for morphology and chondrogenic differentiation. The isolated cells with a fibroblast-like morphology in monolayer culture were positive for the MSC markers CD44, CD105, CD73, and CD90, but negative for the differentiation markers CD34, CD45, CD19, CD14, or major histocompatibility complex class II. Sox9 overexpression induced accumulation of sulfated proteoglycans, without altering the cellular morphology. Immunocytochemistry demonstrated that genetic delivery of Sox9 markedly enhanced the expression of aggrecan and type II collagen in hUC-MSCs compared with empty vector-transfected counterparts. Reverse transcription-polymerase chain reaction analysis further confirmed the elevation of aggrecan and type II collagen at the mRNA level in Sox9-transfected cells. Taken together, short-term Sox9 overexpression facilitates chondrogenesis of hUC-MSCs and may thus have potential implications in cartilage tissue engineering.
Assuntos
Humanos , Diferenciação Celular/genética , Condrogênese/genética , Sangue Fetal/citologia , Células-Tronco Mesenquimais/citologia , Fatores de Transcrição SOX9/genética , Agrecanas/biossíntese , Western Blotting , Cartilagem/metabolismo , Proliferação de Células/genética , Condrócitos/metabolismo , Colágeno Tipo II/biossíntese , Citometria de Fluxo , Proteínas de Fluorescência Verde , Regulação da Expressão Gênica/fisiologia , Células Endoteliais da Veia Umbilical Humana/citologia , Imuno-Histoquímica , Imunofenotipagem , Cultura Primária de Células , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Engenharia Tecidual , TransfecçãoRESUMO
The pathophysiology of stroke is complex and involves an abnormal interaction between vessel wall and platelets. Of late many genetic and environmental factors impinging on the vessel wall have been identified which may determine the susceptibility of an individual to stroke. These include elevated homocysteine levels, chronic chalymydial and periodontal infection, plaque characteristics and genetic susceptibility. Intervention with HMG CO enzyme A reductase inhibitors, Angiotensin Enzyme Inhibitors and vitamins have been shown to offer protection.