title: Incorporation of aligned PCL-PEG nanofibers into porous chitosan scaffolds improved the orientation of collagen fibers in regenerated periodontium.
abstract: The periodontal ligament (PDL) is a group of highly aligned and organized connective tissue fibers that intervenes between the root surface and the alveolar bone. The unique architecture is essential for the specific physiological functionalities of periodontium. The regeneration of periodontium has been extensively studied by researchers, but very few of them pay attention to the alignment of PDL fibers as well as its functionalities. In this study, we fabricated a three-dimensional multilayered scaffold by embedding highly aligned biodegradable poly (ε-caprolactone)-poly(ethylene glycol) (PCE) copolymer electrospun nanofibrous mats into porous chitosan (CHI) to provide topographic cues and guide the oriented regeneration of periodontal tissue. In vitro, compared with random group and porous control, aligned nanofibers embedded scaffold could guide oriented arrangement and elongation of cells with promoted infiltration, viability and increased periodontal ligament-related genes expression. In vivo, aligned nanofibers embedded scaffold showed more organized arrangement of regenerated PDL nearly perpendicular against the root surface with more extensive formation of mature collagen fibers than random group and porous control. Moreover, higher expression level of periostin and more significant formation of tooth-supporting mineralized tissue were presented in the regenerated periodontium of aligned scaffold group. Incorporation of aligned PCE nanofibers into porous CHI proved to be applicable for oriented regeneration of periodontium, which might be further utilized in regeneration of a wide variety of human tissues with a specialized direction.
  
  
  CONCLUSIONS
  The regeneration of periodontium has been extensively studied by researchers, but very few of them give attention to the alignment of periodontal ligament (PDL) fibers as well as its functionalities. The key issue is to provide guidance to the orientation of cells with aligned arrangement of collagen fibers perpendicular against the root surface. This study aimed to promote oriented regeneration of periodontium by structural mimicking of scaffolds. The in vitro and in vivo performances of the scaffolds were further evaluated to test the topographic-guiding and periodontium healing potentials. We also think our research may provide ideas in regeneration of a wide variety of human tissues with a specialized direction.
authors.affiliation: State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, PR China.
authors.forename: Wenlu
authors.initials: W
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Advanced Technologies of Material, Minister of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China.
authors.forename: Long
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Stomatology, Peking Union Medical College Hospital, Beijing 100730, PR China.
authors.forename: Ding
authors.initials: D
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Oral Diseases, West China School of Stomatolgy, Sichuan University, Chengdu 610041, PR China.
authors.forename: Shishu
authors.initials: S
authors.lastname: Huang
authors.affiliation: State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, PR China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Jing
authors.affiliation: Department of Stomatology, Affiliated Hospital of Chengdu University of TCM, Chengdu 610075, PR China.
authors.forename: Yeke
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, PR China. Electronic address: hx_zhaozhihe@tom.com.
authors.forename: Zhihe
authors.initials: Z
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Oral Diseases, Department of Orthodontics, West China School of Stomatology, Sichuan University, Chengdu 610041, PR China. Electronic address: zhaolixing1228@hotmail.com.
authors.forename: Lixing
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Advanced Technologies of Material, Minister of Education, School of Materials Science and Engineering, Southwest Jiaotong University, Chengdu 610031, PR China. Electronic address: shaobingzhou@swjtu.edu.cn.
authors.forename: Shaobing
authors.initials: S
authors.lastname: Zhou
mesh_terms: D000818:Animals; D002113:Calcification, Physiologic; D002448:Cell Adhesion; D048430:Cell Shape; D002470:Cell Survival; D048271:Chitosan / Q000737:chemistry*; D003094:Collagen / Q000378:metabolism*; D004195:Disease Models, Animal; D005260:Female; D005786:Gene Expression Regulation; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D010012:Osteogenesis / Q000235:genetics; D010513:Periodontal Ligament / Q000378:metabolism / Q000473:pathology; D010519:Periodontium / Q000502:physiology*; D011091:Polyesters / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D016062:Porosity; D017207:Rats, Sprague-Dawley; D012038:Regeneration; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D011091:Polyesters; C016240:polycaprolactone; D011092:Polyethylene Glycols; D003094:Collagen; D048271:Chitosan
keywords: Biomimetics; Electrospun scaffold; Oriented regeneration; Periodontal ligament; Periodontal tissue engineering