title: Short-term exposure to dioxin impairs bone tissue in male rats.
abstract: Chronic and sub-chronic studies in rats have previously shown that dioxin-like compounds impair the bone tissue homeostasis. In the present study, tibiae and serum were analyzed to study possible effects of short term dioxin exposure on rats. Two month old (ca. 200g) male rats were injected with 50microg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) kg(-1) bw and tibiae were excised 5d following the exposure. Bone composition, dimensions and strength were analyzed by pQCT and three-point bending test on tibiae. In addition, detailed bone composition was analyzed by optical emission spectroscopy (ICP-OES) and Fourier transform infrared spectrometry (FTIR). Analysis of the serum bone biomarkers procollagen type-I N-terminal propeptide (PINP) and carboxyterminal cross linking teleopeptide (CTX) were also performed. pQCT-results showed alterations in the metaphysis, with a significant decrease in trabecular bone cross-sectional area (-19%, p<0.05) and a significant increase in total bone mineral density (+7%, p<0.05) in TCDD-exposed rats. Analyses of the bones by ICP-OES and FTIR showed that bones from exposed rats had a higher relative proportion of crystalline phosphate (+13% for a1080 and +11% for a1113, p<0.05) and lower acid phosphate content (-22% for a1145, p<0.05), resembling the composition of more mature bones. Serum analysis showed that the bone formation marker PINP was decreased (-37%, p<0.05) and that the bone resorption marker CTX was increased (+14%, p<0.05) indicating a net loss of bone tissue. In conclusion, 5d of exposure to TCDD was sufficient to negatively affect bone tissue in male rats.
authors.affiliation: Institute of Environmental Medicine, Division of Biochemical Toxicology, Karolinska Institutet, Nobels väg 13, plan 3, Box 210, S-171 77 Stockholm, Sweden. Electronic address: Monica.Lind@ki.se.
authors.forename: P Monica
authors.initials: PM
authors.lastname: Lind
authors.affiliation: Institute of Environmental Medicine, Division of Biochemical Toxicology, Karolinska Institutet, Nobels väg 13, plan 3, Box 210, S-171 77 Stockholm, Sweden.
authors.forename: Carolina
authors.initials: C
authors.lastname: Wejheden
authors.affiliation: Institute of Environmental Medicine, Division of Biochemical Toxicology, Karolinska Institutet, Nobels väg 13, plan 3, Box 210, S-171 77 Stockholm, Sweden.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Lundberg
authors.affiliation: Departamento de Mineralogía y Petrología, Facultad de Ciencias, Universidad de Granada, Avenida Fuentenueva s/n, 18071 Granada, Spain.
authors.forename: Pedro
authors.initials: P
authors.lastname: Alvarez-Lloret
authors.affiliation: Institute of Environmental Medicine, Division of Biochemical Toxicology, Karolinska Institutet, Nobels väg 13, plan 3, Box 210, S-171 77 Stockholm, Sweden.
authors.forename: Sanne A B
authors.initials: SAB
authors.lastname: Hermsen
authors.affiliation: Departamento de Mineralogía y Petrología, Facultad de Ciencias, Universidad de Granada, Avenida Fuentenueva s/n, 18071 Granada, Spain.
authors.forename: Alejandro B
authors.initials: AB
authors.lastname: Rodriguez-Navarro
authors.affiliation: Department of Surgical Sciences, Orthopaedics, Uppsala University, Sweden.
authors.forename: Sune
authors.initials: S
authors.lastname: Larsson
authors.affiliation: Institute of Environmental Medicine, Division of Work Environment Toxicology, Karolinska Institutet, Box 210, S-171 77 Stockholm, Sweden.
authors.forename: Agneta
authors.initials: A
authors.lastname: Rannug
mesh_terms: D000818:Animals; D015519:Bone Density / Q000187:drug effects; D001842:Bone and Bones / Q000187:drug effects*; D008297:Male; D010710:Phosphates / Q000378:metabolism; D010748:Phosphopeptides / Q000097:blood; D000072317:Polychlorinated Dibenzodioxins / Q000008:administration & dosage / Q000031:analogs & derivatives*; D011347:Procollagen / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D017550:Spectroscopy, Fourier Transform Infrared; D013977:Tibia / Q000187:drug effects; D014057:Tomography, X-Ray Computed
chemical_list: C062121:N-propeptide type I collagen; D010710:Phosphates; D010748:Phosphopeptides; D000072317:Polychlorinated Dibenzodioxins; D011347:Procollagen