title: The in vivo underlying mechanism for recovery response formation in nano-titanium dioxide exposed Caenorhabditis elegans after transfer to the normal condition.
abstract: So far, we still know little about mechanism for recovery response of engineered nanomaterials (ENMs). Here we used Caenorhabditis elegans to investigate recovery responses of titanium dioxide nanoparticles (TiO2-NPs) exposed animals and the underlying mechanism. After acute exposure to TiO2-NPs (100mg/L), endpoints including defecation and permeable state of intestinal barrier of exposed nematodes returned to control levels; however, after prolonged exposure to TiO2-NPs (100μg/L), endpoints of exposed nematodes could not be recovered to control levels under the normal condition. After prolonged exposure to TiO2-NPs, nematodes exhibited severe deficits in development of intestinal barrier and AVL and DVB neurons controlling defecation; however, after acute exposure to TiO2-NPs, nematodes had normal developmental state of intestinal barrier and AVL and DVB neurons. Our results imply that developmental states of intestinal barrier and AVL and DVB neurons may serve as a pivotal determinant for recovery response in TiO2-NPs exposed nematodes.
  
  
  BACKGROUND
  This basic science study investigates the recovery response to TiO2 nanoparticles in a nematode model, and concludes that developmental states of the intestinal barrier and AVL and DVB neurons likely serve as determinants for recovery following TiO2-NP exposure.
authors.affiliation: Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School of Southeast University, Nanjing 210009, China.
authors.forename: Yunli
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School of Southeast University, Nanjing 210009, China.
authors.forename: Qiuli
authors.initials: Q
authors.lastname: Wu
authors.affiliation: School of Public Health, Southeast University, Nanjing 210009, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Tang
authors.affiliation: Key Laboratory of Environmental Medicine Engineering in Ministry of Education, Medical School of Southeast University, Nanjing 210009, China. Electronic address: dayongw@seu.edu.cn.
authors.forename: Dayong
authors.initials: D
authors.lastname: Wang
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000187:drug effects*; D003672:Defecation / Q000187:drug effects; D007422:Intestines / Q000187:drug effects*; D053758:Nanoparticles / Q000633:toxicity*; D009474:Neurons / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D014025:Titanium / Q000633:toxicity*
chemical_list: D017382:Reactive Oxygen Species; C009495:titanium dioxide; D014025:Titanium
keywords: Caenorhabditis elegans; Defecation; Intestinal barrier; Recovery response; TiO(2)-NPs