title: Poly(lactic-co-glycolic) acid/nanohydroxyapatite scaffold containing chitosan microspheres with adrenomedullin delivery for modulation activity of osteoblasts and vascular endothelial cells.
abstract: Adrenomedullin (ADM) is a bioactive regulatory peptide that affects migration and proliferation of diverse cell types, including endothelial cells, smooth muscle cells, and osteoblast-like cells. This study investigated the effects of sustained release of ADM on the modulation activity of osteoblasts and vascular endothelial cells in vitro. Chitosan microspheres (CMs) were developed for ADM delivery. Poly(lactic-co-glycolic) acid and nano-hydroxyapatite were used to prepare scaffolds containing microspheres with ADM. The CMs showed rough surface morphology and high porosity, and they were well-distributed. The scaffolds exhibited relatively uniform pore sizes with interconnected pores. The addition of CMs improved the mechanical properties of the scaffolds without affecting their high porosity. In vitro degradation tests indicated that the addition of CMs increased the water absorption of the scaffolds and inhibited pH decline of phosphate-buffered saline medium. The expression levels of osteogenic-related and angiogenic-related genes were determined in MG63 cells and in human umbilical vein endothelial cells cultured on the scaffolds, respectively. The expression levels of osteogenic-related and angiogenic-related proteins were also detected by western blot analysis. Their expression levels in cells were improved on the ADM delivery scaffolds at a certain time point. The in vitro evaluation suggests that the microsphere-scaffold system is suitable as a model for bone tissue engineering.
authors.affiliation: VIP Integrated Department, School of Stomatology, Jilin University, 1500 Qinghua Road, Changchun 130021, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Wang
authors.forename: Chunyan
authors.initials: C
authors.lastname: Li
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Chen
authors.forename: Shujun
authors.initials: S
authors.lastname: Dong
authors.forename: Xuesi
authors.initials: X
authors.lastname: Chen
authors.forename: Yanmin
authors.initials: Y
authors.lastname: Zhou
mesh_terms: D053607:Adrenomedullin / Q000008:administration & dosage* / Q000737:chemistry; D001672:Biocompatible Materials; D048271:Chitosan / Q000737:chemistry*; D016503:Drug Delivery Systems; D042783:Endothelial Cells / Q000187:drug effects; D061307:Human Umbilical Vein Endothelial Cells / Q000187:drug effects; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D008863:Microspheres; D010006:Osteoblasts / Q000166:cytology / Q000187:drug effects; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D016062:Porosity; D023822:Tissue Engineering
chemical_list: D001672:Biocompatible Materials; D053607:Adrenomedullin; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D048271:Chitosan