title: Efficacy of the hatching event in assessing the embryo toxicity of the nano-sized TiO₂ particles in zebrafish: a comparison between two different classes of hatching-derived variables.
abstract: The aim of the present study was to evaluate the nano-TiO2 toxicity to zebrafish embryos through evaluating the success in hatching in relationship with hours post-exposure instead of considering just the total hatching rate. Zebrafish embryos 4h post-fertilization were exposed to nTiO2 (0, 0.01, 10, and 1000 µg mL(-1)) for 130 h. The hatching rate (HR) was calculated for each concentration (treatment). The HR magnitude was significantly (p<0.001) correlated (using simple regression) to hours post-exposure time interval (hpe; 34, 58, 82, 106, and 130), noted as HR.hpe. The HR descriptive statistics (HRds) and the parameters of the regression models (i.e., constant, x, F, and r(2)) were recruited to define 15 HRds- and 4 h.hpe-derived variables, respectively. The efficacy of the variables was evaluated. Exposure to nTiO2 led to a significant: premature hatching and general decrease in time required for normal hatching; and change in HR and hpe interrelations in a dose-dependent manner. The major change in hatchability between the treatment and control occurred at 58 hpe (62 hpf), when the treatment with nTiO2 induced significant premature hatching compared to only 6% of the hatched embryos in the control at the same time point. EC10 and EC50 values that cause premature hatching at 58 hpe for nTiO2 are 0.073 µg mL(-1) and 107.2 µg mL(-1) respectively. In general(,) this study shows multivariate differences among exposure concentrations of nTiO2 recruiting hatching-derived endpoints.
authors: Urmia Lack Research Institute, University of Urmia, P.O. Box 165, Urmia, Iran. Electronic address: mohamadreza_samaee@yahoo.com.
authors: Seyed-Mohammadreza
authors: SM
authors: Samaee
authors: Experimental Research Laboratory, Tehran Heart Center, Tehran University of Medical Sciences, Iran.
authors: Shahram
authors: S
authors: Rabbani
authors: Chair for Fish Diseases and Fisheries Biology, Faculty of Veterinary Medicine, Ludwig Maximilian University of Munich, Munich, Germany.
authors: Boris
authors: B
authors: Jovanović
authors: Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran 14114-13137, Iran.
authors: Mohammad Reza
authors: MR
authors: Mohajeri-Tehrani
authors: Endocrinology and Metabolism Research Institute, Tehran University of Medical Sciences, Tehran 14114-13137, Iran.
authors: Vahid
authors: V
authors: Haghpanah
mesh_terms: D000818:Animals; D004625:Embryo, Nonmammalian / Q000187:drug effects*; D004785:Environmental Pollutants / Q000633:toxicity*; D053758:Nanoparticles / Q000633:toxicity*; D014025:Titanium / Q000633:toxicity*; D015027:Zebrafish / Q000196:embryology* / Q000254:growth & development
chemical_list: D004785:Environmental Pollutants; C009495:titanium dioxide; D014025:Titanium
keywords: Embryos; Hatching; NM-105; Nanoparticles; Titanium dioxide; Zebrafish