Running has a negative effect on bone metabolism and proinflammatory status in male aged rats.
Animal models for male osteoporosis are scarce. This study aimed at identifying the impact of different living conditions on bone structure and metabolism as well as the inflammatory status in a rat model of age-related male osteoporosis. Bone mineral density, bone histomorphometric data, ex vivo osteoclast generation, and bone metabolism serum marker as well as intracellular cytokine expressions were evaluated in 23-month-old male Sprague-Dawley rats subjected to different housing conditions from the age of 5 months. Running rats were housed individually and were exercised voluntarily in running wheels attached to their cages. Dieting rats were housed individually, too, but were fed to pair weight with the running rats. Walking rats were exercised mildly by use of a treadmill (800m/day, 5 days a week) and social rats were kept as four in a cage and fed ad libitum. Whereas no marked differences could be found for bone mineral density, trabecular bone volume as well as trabecular bone surface were diminished in walking rats. The ex vivo osteoclast generation assay revealed no significant differences between groups. Osteoblasts of running rats were not only decreased in number, but displayed also a lower activity as indicated by decreased serum osteocalcin levels. Osteoclast activity was increased in the same group as indicated by elevated CTX (c-terminal telopeptide of type I collagen) levels. Additionally, production of tumor necrosis factor (TNF)-alpha and interferone (IFN)-gamma by CD8(+) T cells was elevated in running rats. In conclusion, running has a negative effect on bone metabolism and proinflammatory status in male aged rats.
Sipos
Wolfgang
W
II. Medical Clinic, University of Veterinary Medicine Vienna, Veterinärplatz 1, A-1210 Vienna, Austria. wolfgang.sipos@vu-wien.ac.at
Rauner
Martina
M
Skalicky
Monika
M
Viidik
Andrus
A
Hofbauer
Günther
G
Schett
Georg
G
Redlich
Kurt
K
Lang
Susanna
S
Pietschmann
Peter
P
D000135:Acid Phosphatase / Q000097:blood; D000375:Aging / Q000276:immunology / Q000378:metabolism*; D000818:Animals; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D001842:Bone and Bones / Q000378:metabolism*; D056657:Cathepsin K; D002403:Cathepsins / Q000097:blood; D002452:Cell Count; D024042:Collagen Type I / Q000097:blood; D016207:Cytokines / Q000032:analysis / Q000276:immunology; D005434:Flow Cytometry; D007527:Isoenzymes / Q000097:blood; D008297:Male; D023421:Models, Animal; D015675:Osteocalcin / Q000097:blood; D010010:Osteoclasts / Q000502:physiology; D053244:Osteoprotegerin / Q000097:blood; D010455:Peptides / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D012420:Running / Q000502:physiology*; D013601:T-Lymphocytes / Q000276:immunology; D000071681:Tartrate-Resistant Acid Phosphatase
D015415:Biomarkers; D024042:Collagen Type I; D016207:Cytokines; D007527:Isoenzymes; D053244:Osteoprotegerin; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D002403:Cathepsins; D056657:Cathepsin K; C534133:Ctsk protein, rat